금속압력용기의 사용 전 음향방출시험

이종오,윤운하,이태희,이종규 한국비파괴검사학회 2003 한국비파괴검사학회지 Vol.23 No.3

사용하지 않은 새 금속 압력용기에 대하여, 사용 전 음향방출시험을 수행할 때 장비점검, 탐촉자 간 거리, 탐촉자 위치, 전 측정 시스템 점검, 가압방법, 잡음 제거법 및 시험 결과의 평가 등에 대한 절차를 수립하고 현장 응용시험이 수행되었다. 일반적으로 음향방출 시험은 많은 잡음을 포함하는데 시험동안 관찰결과를 기록하여 평가 시 시간 필터링함으로서 잡음을 제거할 수 있었다. The field application of acoustic emission(AE) testing for brand-new metal pressure vessel were performed. We will introduce the test procedure for acoustic emission test such as instrument check, distance between sensors, sensor location, whole system calibration, pressurization sequence, noise reduction and evaluation. The data of acoustic emission test contain many noise signal, these noise can be reduced by time filtering which based on the description of observation during AE test.

<tex> ${\rm TmBa}_{2}{\rm Cu}_{3}{\rm O}_{7-{\rm x}}$</tex> Superconducting Thin Films Grown by Pulsed Laser Deposition

Rock-Kil Ko,O-Jong Kwon,Kyu-Jeong Song,Ahmad, D.,Chan Park,Joon-Ho Lee,Seung-Su An,Nam-Jin Lee,Sang-Soo Oh,Young-Cheol Kim Institute of Electrical and Electronics Engineers 2007 IEEE transactions on applied superconductivity Vol.17 No.2

<P>TmBa<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7</SUB> <SUB>-</SUB> <SUB>x</SUB> films which is one of the (Rare earth)Ba<SUB>2</SUB>Cu<SUB>3</SUB>O<SUB>7</SUB> <SUB>-</SUB> <SUB>x</SUB> high temperature superconductors with small ionic radius of rare earth element, were deposited on STO (100) single crystal substrates and Y<SUB>2</SUB>O<SUB>3</SUB>/YSZ/CeO<SUB>2</SUB> buffered metal substrates by pulsed laser deposition. The J<SUB>c</SUB> (77 K) and the value of onset of Tc TmBCO thin film on STO substrate was 4.5 MA/cm<SUP>2</SUP> and 86 K, respectively. The of J<SUB>c</SUB> TmBCO coated conductor on metal substrate was 1 MA/cm<SUP>2</SUP> . In-field property measurement was carried out at temperatures between 10 K and 77 K in magnetic filed up to 6 T in PPMS system. This is the first report, to the best of our knowledge, of TmBCO thin films and coated conductors with TmBCO film as the superconducting layer which have critical current densities at 77 K of 4.5 MA/ cm<SUP>2</SUP> and 1 MA/cm<SUP>2</SUP> , respectively. The superconducting properties of TmBCO films and the possibility of using TmBCO film as the superconducting layer of the HTS coated conductor, were investigated.</P>

<i>Deqi</i> Induction by HT7 Acupuncture Alters Theta and Alpha Band Coherence in Human Healthy Subjects

Lee, Go-Eun,Yun, Jong-Min,Yang, Seung-Bum,Kang, Yeonseok,Kang, Hyung-Won,Choi, Kwang-Ho,Kim, Junbeom,Kwon, O. Sang,Park, Ji-Eun,Kim, Jae-Hyo Hindawi 2017 Evidence-based Complementary and Alternative Medic Vol.2017 No.-

<P>The aim of this preliminary study is to investigate the changes in phase synchronization in the theta and alpha bands before and during the performance of classical acupuncture on the Sinmun (HT7). The electroencephalogram (EEG) signals from nine healthy young subjects were recorded before and during acupuncture in the “closed-eye” state. The EEG signals were acquired from 19 surface scalp electrodes (FP1, FP2, F7, F3, Fz F4, F8, T3, C3, Cz, C4, T4, T5, P3, Pz, P4, T6, O1, and O2). Needles were inserted into the HT7 bilaterally and were then manipulated to induce<I> deqi</I> and retained for 15 minutes. Phase synchronization was measured by phase coherence. In the theta band, coherence significantly increased between the temporal (T5, T6) and occipital areas (O1, O2) during the acupuncture stimulation. In the alpha band, coherence significantly increased between the left temporal area (T5) and other areas (frontal, parietal, and occipital). Phase coherence in the theta and alpha bands tended to increase during the retention of the acupuncture needles after<I> deqi</I>. Therefore, it can be concluded that acupuncture stimulation with<I> deqi</I> is clinically effective via the central nervous system (CNS).</P>

虹彩 體質 分析에서 心腎結合組織의 虛弱 體質과 高血壓 家族歷과 관련성 硏究

金鐘牛,黃祐準,琴坰樹,李始炯,李宗淳,都金錄,趙在運,趙州掌,金鐘煜 한국전통의학연구소 2002 한국전통의학지 Vol.12 No.1

Iridology, developed more than 100 years ago, is the diagnosis of medical conditions through noting irregularities of the pigmentation in the iris The purpose of this study is to compare interrelation between CVA, hypertension family history and cardio-renal connective tissue in Iris Constitution through iris constitution examination. The subjects consist of 114 patients who were examined in Iris Constitution at Chonju Oriental Medicine Hospital attached to Wonkwang Univ. from September. 1St. 2000 to August. 31th. 2002. 1. In the distribution of Iris Constitution, among of 79cases, There are neurogenic type 13cases, abdominal connective tissue weakness constitution 31 cases, cardio-renal connective tissue weakness constitution 6 cases, cholesterol 7 cases and others 22 case in control group. 2. There are familial history of CVA and hypertention 32 cases, no familial history of CVA and hypertention1 3 cases, in 35cases of experimental group. These results imply that there is meaningfulness of interrelation between cardio-renal connective tissue weakness constitution and. CVA, hypertention.

신경회로망을 이용한 터빈로타 디스크 키웨이의 결함 검출

이병우,이종오,윤운하,이병우,서원찬,이종규 한국비파괴검사학회 2003 한국비파괴검사학회지 Vol.23 No.1

최근 터빈 로타 디스크 키웨이에서 많은 응력부식균열이 발견되었으며, 터빈설비의 중대한 파손을 예방하기 위해 이러한 균열은 조기에 검출 및 평가되어야 한다. 본 연구에서는 초음파탐상의 RF(radio frequency) 신호를 역전파 알고리즘에 근거한 신경회로망에 적용하여 키웨이 주변의 균열에 대한 위치, 크기 및 방향성을 평가하였다. 각 반사영역에서 수신된 여러개의 피크로 나타나는 RF 신호를 각 반사영역에 대해 하나의 최대 피크를 가지도록 처리한 후, 트랜스듀서의 위치 정보와 각 반사파의 도달시간이 들어있는 주사 데이터를 작성하였다. 이 주사 데이터로부터 각 반사영역 사이의 시간차이와 트랜스듀서의 위치 정보를 신경회로망에 적용한 결과 키웨이에서 시작된 균열의 위치, 크기 및 방향성을 평가하는데 유용함을 알 수 있었다. A number of stress corrosion cracks in turbine rotor disk keyway in power plants have been found and the necessity has been raised to detect and evaluate the cracks prior to the catastrophic failure of turbine disk. By ultrasonic RF signal analysis and using a neural network based on back-propagation algorithm, we tried to evaluate the location, size and orientation of cracks around keyway. Because RF signals received from each reflector have a number of peaks, they were processed to have a single peak for each reflector. Using the processed RF signals, scan data that contain the information on the position of transducer and the arrival time of reflected waves from each reflector were obtained. The time difference between each reflector and the position of transducer extracted from the scan data were then applied to the back-propagation neural network. As a result, the neural network was found useful to evaluate the location, size and orientation of cracks initiated from keyway.

Expression Patterns of HIF-1α Under Hypoxia in Vascular Smooth Muscle Cells of Venous Malformations

Chung, Ho Yun,Lee, Seok Jong,Lee, Jong Min,Huh, Seung,Kim, Hyung Kee,Kwon, O Hyun,Lim, Hyun Ju,Oh, Eun Jung,Kim, Tae Jung,O, Teresa M.,Waner, Milton Wolters Kluwer Health, Inc. All rights reserved. 2015 Annals of plastic surgery Vol.75 No.3

PURPOSE: The molecular pathophysiology of venous malformations (VMs), which are a type of vascular malformation, is poorly understood. Until now, it is known that VM lesions are related to the process of angiogenesis. Because angiogenesis is induced under hypoxic conditions, hypoxia is thought to be important in VM lesion formation. Therefore, we examined the implications of hypoxia on the biological behavior of VM vascular smooth muscle cells (VSMCs). In doing so, we investigated the expression patterns of hypoxia-inducible factor-1α (HIF-1α), which plays a key role in hypoxia-induced angiogenesis, to provide a further understanding of the molecular mechanisms involved in VM. METHODS: Vascular smooth muscle cells from 5 normal veins and 5 VM lesions were cultured under moderate hypoxic conditions (3% O2, 5% CO2). The effects of hypoxia on HIF-1α expression were measured by immunocytochemical staining, reverse transcription-polymerase chain reaction, and real-time reverse transcription-polymerase chain reaction. RESULTS: Overall, the expression of HIF-1α in cells was high after exposure to hypoxia for 6 or 12 hours, but decreased after 24 hours of hypoxia. HIF-1α expression in VM VSMCs was 2 times higher than that in normal VSMCs. Immunocytochemically, HIF-1α was mainly located in the nucleus and the intensity in VM VSMCs was stronger after 6 and 12 hours of hypoxia when compared to the expression pattern of HIF-1α in VSMCs from normal tissue. This suggested that VM tissue is more susceptible to the effects of hypoxia than normal tissue. CONCLUSIONS: These results indicate that the high expression of HIF-1α in VM VSMCs under hypoxic conditions could be an important factor for stimulating downstream angiogenesis in VM. Furthermore, the results of this investigation could provide the basis for future studies of VM pathophysiology, and ultimately lead to the development of new therapeutic approaches.

0.75Δ% 굴절율차를 가진 40채널 광파장 다중화 및 역다중화 소자 제작 및 특성

문형명,최기선,이길현,김동훈,이지훈,이동환,오진경,곽승찬,권오관,강동수,최준석,정건,이현용,Moon, H.M.,Choi, G.S.,Lee, K.H.,Kim, D.H.,Lee, J.H.,Lee, D.H.,Oh, J.K,Kwak, S.C.,Kwon, O.K.,Kang, D.S.,Choi, J.S.,Jong, G,Lee, H.Y. 한국광학회 2005 한국광학회지 Vol.16 No.3

[ $0.75delta\%$ ]의 평판광회로(PLC;Planar Lightwave Circuit)소자의 설계 및 제작기술을 가지고 저손실과 높은 누화율을 가진 파장 다중화 및 역다중화 소자를 개발하였다. C-band AWG(Arrayed Waveguide Grating)에서의 삽입손실은 2.503이하, 누화율은 35dB이상, 균일도는 1dB이하이며 L-band에서는 Vernier 디자인을 적용하여 ITU-T의 파장 정확도가 0.04nm이하가 되도록 제작하였다. A 40 channel arrayed-waveguide grating (AWG) filter operating in C-band and L-band wavelength regions has been fabricated using PLC (Planar Lightwave Circuit) processes with 0.75 refractive index difference. Its design was optimized for matching the center wavelength with the ITU-recommended wavelength. The characteristics of the fabricated C-band AWG are as follows; average insertion loss < 2.5 dB, polarization-dependent loss < 0.3 dB, non-adjacent crosstalk >35dB, and the loss uniformity of 0.8 dB. In the L-band AWG, wavelength accuracy is below 0.02nm.

일방성 GFRP 복합재료에서 음향방출 신호의 위치표정

이종오,원순호,윤운하,이종규,소철호 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.3

General source location method that use an arrival time differences among sensor is restricted to the composite material and the complex-shaped material. In this study, a bundle-type acoustic sensor composed of 6 pinducers was utilized to determine wave propagation direction and then to estimate source location of the unidirectional GFRP. For the purpose of the study, slowness curve for the material was obtained and made an assumption that the incident waves on pinducers are propagated as a plane wave. According to the results, measured propagation directions of the wave was coincide with theoretical background, however, it was a hassle to determine the source location exactly. But, it is expected that bundle-type sensor gives more accurate results for zone location than generally used acoustic sensors.

S-상 심실중격의 임상적 고찰

이동민,장경식,양종태,장대용,김종오,서영욱,고영엽,홍순표 조선대학교 부설 의학연구소 2002 The Medical Journal of Chosun University Vol.27 No.1

Background: The sigmoid septum described an anatomical variation in the contour of the left ventricular outlet. It is related to degenerative change with aging. We observed clinical significance of sigmoid septum in Korean. Methods: Echocardiographic examination was performed in 434 patients. Sigmoid septum is defined as discrete bulging of the proximal interventricular septum with that thickness is greater than 1.3cm or the thickness is grater 1.5 times than adjacent mid interventricular septum in apical 3 chamber view. Result: The incidence of patient with sigmoid septum(septum patient) is 24.8% (male 8.4%, female 16.3%) . The incidence increases with age and is more common in women. The patients with sigmoid septum were compared with targeted groups, there was no significant difference in blood pressure between them, but in height and weight, the former were lower. (p<001, p<03). In the patients with sigmoid septum, weight and the surface area of a body have an opposite correlation with increase of age (p<03, r=-0.34) (p<04, r=-0.31) , but no decrease of height was found according to age increase (p=0.47, r=-0.11) The main reason patients with sigmoid septum ask echocardiolography and its clinical symptoms were abnormal results of previous electrocardiography and/or usual chest pain. Compared with control group, interventricular septal thickness is larger in septum patients (p<001). The thickness of interventricular septum located in subaortic left ventricular outflow tract is 1.6±0.3cm. There is another web like structure that continued from interventricualr septum to anterior free wall of left ventricle and the width is 1.6±0.4cm. A sign of insignificant obstruction due to left ventricular outflow was observed from three sigmoid septum patients. Conculusion: Septum patient is largely found in older age group and the body weight and body surface area are lower than control group. The body weight and body surface area are opposite correlation with age. So sigmoid septum is considered as structural change by weight reduction with aging. It is assumed that septum patients are related with asymptomatic ischemia because they have more abnormal ECG finding such as T wave inversion on precordial leads or standard leads, nonspecific ST-T change, LBBB etc. Sigmoid septum is not only proximal interventricular septal bludging but also another web like structure continuing to anterior wall of left ventricle.

방역작업자의 브롬화메틸(methyl bromide) 노출수준과 생물학적 모니터링

이종성,이용학,신재훈,최정근,오차재,정호근 한국산업위생학회 2001 한국산업보건학회지 Vol.11 No.3

This study was performed to estimate environmental and biological monitoring of worker exposed to methyl bromide through quarantine fumigation. Airborne methyl bromide and it's metabolites were analyzed by gas chromatography and ion chromatography, respectively. The results are as followings; airborne concentration of methyl bromide(TWA) was 2.08±1.56 ppm(N=8). Dispersion and setting/degas groups were 0.67±0.12 ppm(N=2) and 2.54±1.53ppm(N=6), respectively. Bromide ion concentration in serum was 23.40±14.91㎎/ℓ(N=10) in the exposed workers and 4.74±0.82㎎/ℓ(N=21) in the non-exposed workers. Bromide ion concentration in urine was 35.56±26.89㎎/ℓ(N=11) in exposed group and 6.62±2.31㎎/ℓ(N=21) in non-exposed group. Good correlation was observed between concentration of serum and urine(r^2=0.890 p<0.01). No significant correlations of other determinanats were observed. Calcuated from a regressive curve. the biological half lifes of serum and urine were 10.7 and 5.9 days. In these results, biological monitoring of bromide ion of serum and urine provided useful information for evaluating exposure of workers to methyl bromide, so that an availability of bromide ion of biological samples was showed as biological monitoring indices for methyl bromide.