Simplified Effective Compressive Strengths of Columns with Intervening Floor Slabs

Seung?Ho Choi,Jin?Ha Hwang,Sun?Jin Han,Hae?Chang Cho,Jae Hyun Kim,Kang Su Kim 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.5

The current design codes discuss the effective compressive strengths of columns, which reflect a decrease in load transfer performance that can occur when columns and slabs have different concrete compressive strengths. The effective compressive strength of a column increases as it is confined by the slab, and the design codes mandate three different effective compressive strengths for interior columns (confinement on four sides), exterior columns (confinement on three sides), and corner columns (confinement on two sides). For both corner and exterior columns, the confinement effect of the slab is significantly smaller than that for the interior column, and there is a more marked decrease in load transfer performance. However, there is still a lack of theoretical studies investigating the effective compressive strengths of the corner and exterior columns. Therefore, based on the analysis model established in previous research, this study has proposed an equation for calculating the effective compressive strengths of the corner, exterior and isolated columns without any confinement effects of the slab. In addition, axial loading tests of isolated columns were conducted and the proposed equation was verified.

내시경적 점막절제술로 치험한 식도 과립상 세포종 1례

강혁주,김성욱,최석진,이중현,장재식,서영범,윤병구,박건욱,김성자,김용섭,강승완,이구,양창헌,이창우,김욱년,이광헌,서정일 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

과립상 세포종은 Schwann 세포 기원으로 생각되며 인체에 비교적 드물게 발생한다. 과립상 세포종은 전신 어느 곳에서나 발견될 수 있으나 주로 혀, 구강, 피부 혹은 유방 등에서 호발하며 드물게 위장관에서 발견된다. 위장관에서는 식도에서 가장 호발하며 다음으로 위, 대장 순이다. 과립상 세포종은 대부분, 특히 위장관에서는 양성이며 소수의 악성 병변이 보고되었다. 이러한 이유와 함께 수술 전의 진단이 어렵기 때문에 과립상 세포종에 대한 근본적인 치료는 현재까지 외과적 절제술이다. 최근에 시도되는 치료방법들로는 내시경적 레이저 치료, 용종절제술, 내시경적 점막 절제술 등이 있다. 저자들은 상부 소화관 내시경검사를 시행하여 식도 과립상 세포종을 진단하고 내시경적 점막 절제술을 시행하여 합병증 없이 퇴원하여 현재 재발없이 경과 관찰중인 1례를 경험하였기에 보고하는 바이다. Granular cell tumors, which occur infrequently, are probably of Schwann cell origin. They can occur almost anywhere in the body but usually affect the tongue, oral cavity, skin, or breasts and are rarely found in the gastrointestinal tracts. The esophagus is the most frequent gastrointestinal site, followed by the stomach and the colon. Granular cell tumors are generally benign, especially in the gastrointestinal tract, some malignant lesions have been reported. For this reason, and also because preoperative diagnosis is difficult, the standard treatment for granular cell tumor has until now been surgical excision. In recent years, other therapeutic methods is endoscopic laser therapy (ELT), polypectiomy, endoscopic mucosal resection (EMR). We report a case of esophageal granular cell tumor which was diagnosed by an endoscopy and managed using an endoscopic mucosal resection without complication.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.

저면 반사파를 이용한 피로 균열의 정량적 평가에 관한 연구

강승현,이준현,최상우,조윤호 한국비파괴검사학회 2004 학술대회 논문집 Vol.- No.-

Fatigue cracks due to thermal stratification or corrosion in pipelines of nuclear power plants can cause serious problems on reactor cooling system. Therefore, these cracks must be detected before the crack growth to ensure the reliable operation. Ultrasonic techniques have been employed for detecting and sizing these fatigue cracks propagated from the back wall of pipelines. But, it is very difficult to sizing fatigue cracks because of low amplitude of the diffracted tip signal, high noise signal and ultrasound transmission through the closed crack surface. In this study, the signal reflected from the back wall is adopted instead of weak tip signals. In addition, the rate of decrease in amplitude of reflected signals due to reflection at the crack surface and diffraction at the crack tip is used to size fatigue cracks.

교량의 충격계수에 대한 실험 및 해석적 평가에 관한 연구

강승우,최광규,김은진 東亞大學校 建設技術硏究所 2008 硏究論文集 Vol.31 No.2

Highway bridges are subjected to dynamic loads when traversed by the vehicles. The vehicle-induced vibrations of bridge depend on the following factors: vehicle speed, type of bridge and its natural frequencies of vehicle, and the profiles of approach roadway and bridge deck. Impact is generally used to describe the increase in deflection{or stress) due to the dynamic nature of traffic loads, In design phase, therefore, to allow for the effect of dynamic action, the static live load is increased by a impact factor given in bridge design specification. In this study, we consider the impact factor of bridge for vehicle property. Impact fact estimated that the data by traveling test of the real bridge was used experimental method. Also, fortran program was developed about bridge-vehicle interaction. After the modeling of bridge and vehicle does. Impact factor was evaluated analysis method by interaction analysis of the program.

77K와 상온에서 CO(NH₂)₂의 ¹⁴N Pulsed NQR 연구

강재필,박영민,전인,김성재,최숙자,박현진,송승기,서용문 명지대학교 자연과학연구소 1996 자연과학논문집 Vol.13 No.-

77K와 상온에서 CO(NH₂)₂분말 시료의 ??N Pulsed NQR실험을 하여 위와 아래 공명 진동수, 핵 사중극 결합상수, 비대칭 인자, 스핀-스핀 완화시간, 결정 격자 진동에서의 평균 비틀림 진동수, 진동자의 관성 모먼트 등을 구하였다. 공명 진동수의 온도 의존성은 전형적인 Bayer이론의 격자 진동에 의한 주파수 변화를 보였다. Bayer-Kushida이론의 고온근사식을 실험값에 적용하여 OK에서 공명 진동수 ν??와 ν??를 구했으며, 77K와 상온에서의 스핀-스핀 완화시간 T₂를 관측했다. 상온에서 T₂의 감소는 결정 내의 reorientation motion과 관련이 있을 것으로 보인다. Upper and lower resonance frequencies, nuclear quadrupole coupling constants, asymmetry parameters, spin-spin relaxation time, average torsional frequency in the crystal lattice motion and moment of inertia in the oscillator are found for CO(NH₂)₂powder sample by using ??N Pulsed NQR(Nuclear Quadrupole Resonance) technique at 77K and room temperature. Temperature dependence of resonance frequencies showed frequency variation in agreement with the typical Bayer's theory in lattice motion. Resonance frequencies ν?? and ν?? at OK were obtained by fitting the high temperature approximation of Bayer-Kushida theory to the experimental data and spin-spin relaxation time (T₂) was observed at 77K and room temperature. Decrease of T₂at room temperature was explained by the effect of reorientational motion in the crystal lattice.

좌심실내 혈류 전파 속도에 관한 연구

최시완,정진옥,강승식,성인환,박종훈 충남대학교 의과대학 지역사회의학연구소 1995 충남의대잡지 Vol.22 No.1

Background : Noninvasive attemps to identify left ventricular relaxation have been hampered because relaxation rate, left atrial filling pressure, and chamber compliance are the major determinants of peak early velocity and filling rate. This study was perfomed to evaluate the relation between the velocity of flow propagation and left ventricular relaxation by using pulsed doppler echocardiography to analize flow propagation in the left ventricle. Method : By using pulsed Doppler echocardiography, the velocity of left ventricular flow propagation was measured from the distance and time difference of flow wave along the long axis propagation of left ventricular inflow during early filling in normal subjects (n=30), and M-mode echocardiographic data were obtained to evaluate mitral annulus long axis movement (mitral annulus relaxation rate) which represents left ventricular relaxation. Results : the peak early velocity was not related to mitral annulus relaxation rate, but, the velocity of flow propagation was related to mitral annulus relaxarate (P<0.005) in normal subjects. Conclusion : the velocity of flow propagation during early filling seems to be highly dependent on the mitral annulus relaxation rate and could be an important noninvasive tool in studying diastolic function.

1회선 분기점을 갖는 병행 2회선 송전선로의 고장점 표정 알고리즘

강상희,권태원,최면송,이승재 明知大學校 産業技術硏究所 2000 産業技術硏究所論文集 Vol.19 No.-

This paper presents a fault location algorithm of a single phase-to-ground fault on a parallel transmission line which contains a teed circuit. The method uses only the local end voltage and current signals. Zero sequence currents of other lines are calculated by distribution factors. Instead of zero sequence current, negative sequence current is used to remove the effect to load current and to calculate the voltage of a fault resistance. There are two distance equations in this algorithm. One of them is to calculate inner part fault location of the tap distance and the other equation is for outer part fault location of the tap distance, Correct fault distance is selected by the condition of each solution. Extensive simulation studies using EMTP have verified that the proposed algorithm can calculate an accurate fault distance in spite of effects of various error sources.

스트레스 반응 척도의 수정판 개발 및 타당화 연구 : 근로자 대상

최승미,강태영,우종민 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.6

Objectives : The purpose of this study is to develop and validate a modified form of the Stress Response Inventory (SRI-MF) for workers. Methods : In study I, the Stress Response Inventory was conducted in 3,420 person, who worked for public institutions andlarge corporations. They were selected from 10 areas throughout the country. After we performed experimental factor analysis in order to select the items by internal consistency and factor loadings, we developed the short form of SRI (SRI-MF). In Study II, SRI-MF was validated by showing convergent/divergent validity with other stress-measuring instruments in another samples. Results : In study I, factor analysis yielded 5 factors, and two of them were excluded because of their low internal consistency. Consequently, total 22 items in the remaining 3 factors (somatization, depression, anger) were selected for the SRI-MF. Test-retest reliability of the SRI-MF was significantly high, ranging between .67-.71. Cronbach's α was also high. In study II, convergent validity was computed by correlating scores of other scales (GARS, SCL-90-R, PSQ) score. The correlations were all at significant levels. Discriminant validity was computed by comparing the total score and scores of 3 subscales in the patient and normal group. There were significant differences in the total and scores of 3 subscales between the two groups. Conclusion : The results of identifying factor structure in the SRI indicated 5 significant factors. Among them, 3 factors can be employed for the modified form of SRI with a high internal consistency. Thus, we suggest that the SRI-MF should be a effective and valid scale to evaluate stress response in work places.

방광의 이행상피암에서 p53과 PCNA 분포에 관한 연구

최은정,강상균,양승하,김대중,김의한 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.2

Immunohistochemical studies were carried out to observe the expression of p53 protein and PCNA in transitional cell carcinoma (TCC), then analyzed according to the tumor grade and progression. 38 cases of TCC consist of 13 cases grade Ⅰ, 12 cases grade Ⅱ and 13 cases grade Ⅲ respectively. Results obtained are as follows. 1. p53 protein expression was seen in 60% of cases(15 out of 38 cases) In the poorly differentiated area and infiltrated lesion, tumor cell showed more strong positive reaction of p53 protein compared with well differentiated area. 2. All of 38 cases of TCC showed PCNA positive expression. The more strong positivity was seen in the poorly differentiated area and the more intense positive reaction was noted in the basal layer of the tumor nests. 3. The above results showed that positivity of p53 protein and PCNA are closely related with tumor cell differentiation(grade) and progression. It is concluded that positive reaction of p53 protein and PCNA may contribute to detection of tumor growth and prognosis of patient.