SASW 기법을 이용한 모래토조의 균질성 평가

조성호 中央大學校 建設環境硏究所 1997 環境科學硏究 Vol.8 No.-

Small scale model tests to investigate geotechnical structures are performed usually on a sand box, which models an ideal homogeneous material. Efforts to obtain ideal homogeneity in a sand box lead to the use of raining method to place sand into a box. In most cases, verification on homogeneity is limited to the check of relative density at selected locations in a sand box by measuring unit weight of a small can. In this study, more extensive and effective approach to check homogeniety of a sand box, which is based on SASW (Spectral-Analysis-of-Surface-Waves) technique, is proposed. The proposed method is called "tomographic SASW", and generates a 2-D contour diagram of lateral and vertical variability of material stiffness, which visualizes the state on homogeneity of a sand box.

SASW 기법에 의한 분니 발생개소의 지반특성에 관한 연구

조성호,강태호,김정근,오상덕 中央大學校 建設環境硏究所 1999 環境科學硏究 Vol.9 No.2

The railroad transportation system has more advantages over other transportation systems in terms of low cost, safety and mass transportation. The development in economy and social environments lead to the increase of the transportation between cities. As a result, the increased capacity of transportation system is required and maintenance of transportation facilities becomes more important. In the railroad system, mud-pumping is one of the troubles to cause distortion of rails and progressive disrupture of subgrade. In this study, SASW measurements were performed to investigate stiffness structures at the sites with mud-pumping and without mud-pumping. Comparison of the stiffness structures revealed the mechanism of mud-pumping and provided information to choose measures for the mud-pumping.

위상속도 측정에 있어서 고차모드 영향을 고려하기 위한 다채널 표면파 기법

조성호,강태호 중앙대학교 건설환경연구소 2000 環境科學硏究 Vol.11 No.2

In early 1980's, Stokoe et, al.(1984) applied the surface wave method, which was used for the global structure investigation and oil exploration, to the engineering domain. Originally, the surface wave method has a basic assumption that the measured stress wave has mostly the component of surface waves and also that the surface wave is governed by the fundamental mode. The early stage of the study on SASW method was focused on the validity of the basic assumptions of the surface wave. Recently, with more applications of SASW method, the more study to increase reliability and resolution of the SASW results was carried out by many researchers including Gucunski, Rix and Al-Hunaidi. In this study, the Multi-Channel SASW method, which uses multiple receivers to measure the superposition effects of multiple modes and improves the conventional SASW method, was proposed and the application of the Multi-Channel SASW method to CAU test site was described.

원발성 두개골내 수막종 : 1예 보고 A Case Report

김대호,홍현숙,조준희,박재성,박성진,차장규,백상현,이혜경 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

Primary intraosseous meningioma of skull is rare, and often confused with a primary bone tumor. We report a case of a 71 years old female patient with an intraosseous calvarial meningioma of frontal bone presenting as a solitary osteolytic skull lesion. Plain skull radiograph, CT and MR images show sharply marginated expansile bony lesion in frontal skull vault, and a small well enhanced soft tissue mass within bone. The mass is extracranially protruded to scalp, and is partially attached to the underlying dura. Outer and inner table of skull vault is slightly bulged out, suggesting intradiploic origin of the tumor. The tumor was treated with surgical excision and cranioplasty. Histological examination revealed fibrous meningioma.

관상정맥동과의 연결이 없는 좌상대정맥의 CT 소견 : 1예 보고 case report

백상현,박재성,이혜경,홍현숙,김대호,조준희,박성진,차장규 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.2

A persistent left superior vena cava (PLSVC) is the most common thoracic venous anomaly. It is a persistent remnant of a vessel that is present as a counterpart of normal right-sided superior vena cava(SVC) in early embryological development but normally disappears later. Its diagnosis can be confirmed by many noninvasive and invasive tests, or it is incidentally diagnosed at insertion into the left subclavian or jugular vein or thoracic surgery. If it is not associated with other congenital cardiac anomalies, it is usually asymptomatic and hemodynamically insignificant. We describe the chest radiograph and CT findings of bilateral SVC with drainage to left superior intercostal vein, hemiazygos, azygos vein and right SVC, and no connection of coronary sinus.

터널 콘크리트 벽체의 건전도 평가에 대한 연속 웨이브릿(Wavelet)의 적용

추진호,조성호,강태호 中央大學校 建設環境硏究所 2002 環境科學硏究 Vol.13 No.2

터널 라이닝의 두께와 강성(stiffness)의 평가에 웨이브릿(wavelet)을 이용하여 신호 해석의 극대화와 터널의 건전도 평가에 있어서 직접적인 수직 균열의 유무, 위치, 다양한 반사면의 탐지에 관한 웨이브릿해석의 적용성을 평가하였다. 기존의 탄성파 해석은 시간 혹은 주파수의 한 영역에서만 해석이 이루어져 왔으나, Wavelet 해석은 신호처리에 있어서 시간-주파수 영역을 동시에 살펴보면서 해석을 할 수 있다. 본 연구에서는 콘크리트의 두께와 강성 균열을 평가하기 위하여 탄성파 기법의 하나인 충격반향 시험법에 대하여 Wavelet 해석을 시행하였다. 유한요소법의 하나인 ABAQUS를 이용한 수치해석과 실규모 현장시험체에서 시행한 실측 데이터 해석에 연속 Wavelet을 적용하여 보았으며, 그 결과 구조물 내에 존재하는 균열의 존재 여부와 균열의 위치를 확인하는데 Wavelet 기법이 매우 효과적이며, 향상된 신뢰성을 제공함을 확인하였다. The feasibility of the continuous wavelet analysis was evaluated for the nondestructive assessment of the structural integrity of a tunnel concrete liner. The conventional approach to analyze the signal of the wave propagation is focused on just one domain of time or frequency, while the wavelet analysis analyzes both domains of time and frequency. This study introduced the continuous wavelet analysis to interpret and analyze the stress-wave signal in both frequency and time domains for the better identification of the vertical cracks in the tunnel concrete liner. The synthetic stress-wave signals from ABAQUS were used to establish the methodology to employ the wavelet analysis, and later the real measurements at the real-scale tunnel concrete liner were analyzed. As a result, it was concluded that the continuous wavelet analysis is a reliable and effective tool to identify the vertical cracks in the tunnel concrete liner.

NSIP와 BOOP의 고해상전산화단층촬영 소견과 비교

백상현,박재성,차장규,홍현숙,김대호,박성진,조준희,이혜경,최진수 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.2

Purpose: BOOP and NSIP also share similar clinical features such as subacute flu-like illness, the finding of bronchoalveolar lavage, the result of pulmonary function test and more favourable outcome than usual interstitial pneumonia(UIP). The author try to compare the HRCT findings of NSIP with BOOP by pattern and distribution of diseases. Materials and Methods: HRCT findings of histopathologically proven NSIP(Group Ⅰ; 6, Group Ⅱ; 7, Group Ⅲ; 2) in 15 patients(5 male, 10 female, age range, 39-69 years; mean age, 53 years), BOOP in 15 patients(6 male, 9 female, age range, 26-76 years; mean age, 52 years) were reviewed retrospectively. Results: The common pattern of the two diseases was admixed consolidation, ground glass attenuation & reticular densities with/without architectural distortion(NSIP; 53.3%, BOOP; 46.7%). The main component of the pattern wan predominantly consolidation(NSIP; 46.7%, BOOP; 73.3%) and ground glass attenuation(NSIP; 40.0%, BOOP;20.0%). Architectural distotion was more provinent finding with NSIP(mild ; 3, moderate ; 4, severe; 2) compared with BOOP(mild; 7, moderate; 2, severe; 0). The predominant overall distribution was lower lung, peribronchovascular & peripheral lung field in both of the two entities(NSIP;73.3%, BOOP; 73.3%). Peribronchovascular involvement was more common with NSIP(100%) than BOOP(80%), whereas peripheral involvement was more common with BOOP(93.3%) than NSIP(80%). Conclusion: The HRCT findings of NSIP and BOOP were similar in pattern and distribution. But NIP manifested more frequently ground-glass attenuation, whereas BOOP showed more frequently consolidation. Architectural distortion was more severe with NSIP than BOOP. NSIP invoved more frequently peribronchovascular space and BOOP were more common in peripheral lung field.

지진동에 대한 지반응답을 구하기 위한 등가선형해석과 유한요소해석

오창목,조성호,이일화 중앙대학교 건설환경연구소 2001 環境科學硏究 Vol.12 No.2

지진으로 인한 지반의 액상화 평가, 구조물에 대한 동적 응답해석 등을 위한 지반응답해석으로 가장 보편적으로 활용되는 해석은 SHAKE(Schnabel, et at.,1972)를 사용한 등가선형해석이다. 등가선형해석은 비선형 정도가 크지 않은 지진동의 경우에는 합리적인 해석방법이 될수 있지만, 입력지진동에 의해 지반 내에 횡방향으로 큰 변위가 발생할 가능성이 있는 경우 합리적인 해석방법이 될 수 없다. 따라서, 본 연구에서는 등가선형해석과 유한요소해석에 의한 지반응답해석을 실제 현장에 대해 적용하여 각 해석결과를 비교 검토함으로써 각 해석의 특징을 살펴보았고, 이를 바탕으로 보다 합리적인 지반응답해석을 위한 제언을 하였다. 본 연구에서 수행한 지반응답해석은 지하철 9호선 철도 통과예정지역인 반포아파트 부지에 대해 수행되었고, 등가선형해석에 의한 지반응답해석은 SHAKE91에 의해서, 유한요소해석은 상용 유한요소해석 프로그램인 ABAQUS에 의해 수행하였다. The most widely accepted analysis, which evaluates the ground response for the liquefaction analysis and dynamic response analysis of structures, is the linear equivalent analysis such as SHAKE(Schnabel, et al., 1972). The concept of the equivalent linear analysis holds true only when the nonlinearity of the ground material is not significant and the large lateral displacement due to the earthquake loading is not expected. Thus, in this study the equivalent linear analysis and the finite element analysis are applied to evaluate the ground response of the real site, and the characteristics of the each algorithm are compared. The equivalent linear analysis was performed by SHAKE91, and the finite element analysis was performed by ABAQUS.

Carotenoids 식이와 알코올이 혈중 지질 성분에 미치는 영향에 관한 연구

조만희,조성호,김진국 순천향의학연구소 1999 Journal of Soonchunhyang Medical Science Vol.5 No.1

Increasingly, humans are subjected to exposure to various foreign chemicals including drugs, food additives, pollutants. Some of them may be harmful and especially give rise to free radicals during metabolism in the tissues. These radicals such as superoxide, hydroxyl radical and hydrogen peroxide, induce oxidation of the macromolecules, resulting in a variety of damages in the body. However, humans have anti-oxidative mechanisms well developed against these damage. Anti-oxidants such as β-carotene and vitamin A, C, and E, are believed to play a major role in these mechanisms by acting as cofactors. On the basis that alcohol, among human's favorite foods, is one of the most common oxidative chemical, this study was carried out to elucidate biochemical changes in the lipid components of the blood after alcohol administration on Sprague-Dawley (SD) rats. Also, we investigated the effects of carotenoid and β-carotene diets on the alcohol-injected rats. At first, the concentrations of serum lipids were highly increased at alcohol-injected rats for one week (AL-1W), but significantly decreased at those dieted with β-carotene for one week (BC-1W). Second, after 2 weeks, the concentrations of serum lipids were exclusive decreased at alcohol-administrated rats. Third, the lipid concentration was increasing in β-carotene-dieted rats throughout the experiments for 3 weeks. These results may suggest that alcohol can cause damages in the liver, resulting in inflammation and increase of the concentration of serum lipids. Also, β-carotene and carotenoid diets are believed to protect the liver against the oxidative damages by alcohol administration.

공진주ㆍ비틂전단 실험법과 하드웨어 보정

우규석,조성호 중앙대학교 건설환경연구소 2000 環境科學硏究 Vol.11 No.2

Recently, the earthquake-resistant design of civil structures gave rise to the more frequent use of the resonant columnㆍtorsional shear (RCTS) test to evaluate the dynamic properties of soil and rocks. RCTS test has been widely used to obtain the shear modulus and damping factors dependent on the shearing strain and confining pressure. However, the reliability of the measured damping factor and the calibration of the system compliance with respect to damping has been disregarded. The coil-magnet system to drive the resonant column system builds a magnetic field, and subsequently the induced Eddy current dissipates a portion of the driving energy, which causes an additional portion in the damping factor measured by the RCTS system. This study proposed a theoretical basis to calibrate the system compliance with respect to the system damping, and discussed the current approach for the system calibration.