Experimental investigation of lateral displacement of PVD-improved deposit

Chai, Jin-Chun,Xu, Fang Techno-Press 2015 Geomechanics & engineering Vol.9 No.5

Laboratory model tests were conducted to investigate the effect of surcharge loading rate on the magnitude of lateral displacement of prefabricated vertical drains (PVDs) improved deposit. The test results indicate that under the condition that the system had sufficient factor of safety (FS) ($FS{\geq}1.2$), for the similar model ground under the same total applied surcharge load, the lateral displacement increases with the increase of loading rate. The test results have been used to check the validity of a previously proposed method for predicting the maximum lateral displacement, and it shows that the data points are around the middle line of the predicted range, which supports the usefulness of the proposed method. The basic idea of the prediction method is an empirical relationship between the normalized lateral displacement (NLD) and a ration of load to the undrained shear strength of the deposit (RLS). The model test results offer some modifications of the NLD-RLS relationship: (1) instead of a bilinear relationship, NLD-RLS relationship may be entirely nonlinear; (2) the upper bound value of RLS for the proposed method can be used may be limited to 2.1 instead of the originally proposed value of 3.0.

수장부 다한증에 제한적 교감신경절간 절단술의 장기 고찰

채진호(Jin Ho Chai),최봉춘(Bong Chun Choi),이영철(Yong Chul Lee) 대한통증학회 2001 The Korean Journal of Pain Vol.14 No.1

N/A Background: Conventional thoracoscopic sympathectomy or sympathicotomy is an effective method in treating localized hyperhidrosis; however, this may result in a postoperatively compensatory hyper- hidrosis or facial anhidrosis in the treatment of palmar hyperhidrosis. We modified the conventional sympathicotomy by limiting the extent of nerve transection (limited T3 sympathicotomy) since May 199S. However, there are many reports of a good short-term outcome of limited T3 sympathicotomy. Therefore, we reviewed long-term follow-up of limited T3 sympathicotomy based on outcomes analysis using a questionnaire. Methods: Fifty four patients with palmar hyperhidrosis underwent a limited T3 sympathicotomy between May 1998 and March 1999 and had a complete follow-up over two years using a questionnaire (the mean follow-up was 2.6 years). The patients' postoperative satisfaction was determined by their subjective responses to the questionnaires; the degree of compensatory hyperhidrosis, the effects on foot hyperhidrosis, gustatory hyperhidrosis and facial dryness, and recurrence, and patients satisfaction. Results: Of the total, 87% of patients had a compensatory hyperhidrosis and 3.7% of them were disabled. 31.5% of patients showed improvement in foot hyperhidrosis, while 68.5% of patients demonstrated no change or got worse. 31.5% of patients had gustatory hyperhidrosis and facial dryness and 22.2% of patients showed a mild palmar hyperhidrosis. The postoperative patients satisfaction was significantly in 96.3% of patients. Conclusions: The limited T3 sympathicotomy is a highly effective treatment of palmar hyperhidrosis and has a low rate of postoperative compensatory hyperhidrosis, gustatory hyperhidrosis, and facial dryness.

노인환자의 고관절 치환술시 체위와 시간경과에 따른 동맥혈 및 호기말 이산화탄소 분압의 비교

정진헌,이선학,김천숙,안기량,박욱,곽수달,권진형,채원석 대한마취과학회 2001 Korean Journal of Anesthesiology Vol.41 No.5

3,9-Diferuloyl-6-oxopterocarpen Inhibits Wrinkle by Antioxidant Effects for Oxidative Stress

Nam-Jin Lee,Hee-Youl Chai,Sun-Hee Park,Yu-Ri Jung,Chun Mei Lin,Jun Hwan Moon,Sung-Min Park,Hyeong-Bae Pyo,Jong-Koo Kang 한국실험동물학회 2008 Laboratory Animal Research Vol.24 No.3

Matrix metalloproteinases (MMPs) and free radicals such as reactive oxygen species (ROS) caused by ultraviolet (UV) exposure are known to play an important role in photoaging by mediating the degradation of extracellular matrix proteins. In this study, to develop a new anti-photoaging agent, we have synthesized 3,9-diferuloyl-6-oxopterocarpen (DFO), an antioxidant activity and inhibitory effect on type I matrix metalloproteinase (MMP-1) expression. In this study, we investigated the effects of DFO on antioxidantive effects, and inhibitory effects on activity and expression of UVA-induced MMPs in human dermal fibroblasts (HDF). DFO was found to show scavenging activities of radicals and ROS with the IC₅₀ values of 0.2 mM against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 0.05 mM against superoxide radicals in the xanthine/xanthineoxidase system, respectively. Fluorometric assays of the proteolytic activities of MMP-1 were performed using fluorescent collagen substrates. DFO inhibited the activities of MMP-1 in a dose-dependent manner, and the IC₅₀ value calculated from semi-log plot was 0.025 mM. In addition, UVA induced MMP-1 expression was reduced by 85% following treatment with DFO at 0.8 ìM in a dose-dependent manner. The results of clinical study showed that a cream containing 4.8 mM DFO reduced significantly wrinkle formation compared with placebo control. All these results suggest that DFO exert an anti-wrinkle activity acting as an antioxidant and reducing UVA-induced MMP-1 activity, without any significant toxicity and thus DFO could be a promising candidate for anti-aging cosmetic ingredient.

전력선 통신에서의 전자파 장해에 관한 연구

李眞澤(Jin-Taek Lee),千東完(Dong-Wan Chun),朴永鎭(Young-Jin Park),李垣泰(Won-Tae Lee),愼哲宰(Chull-Chai Shin) 대한전기학회 2004 전기학회논문지C Vol.53 No.12

간 전이 소견없이 유암 증후군을 동반한 십이지장 구부의 유암종 1예

배영진,이혜정,김혜숙,최필선,조강일,한경문,천종철,이성욱,박진곤,선병호,문성채 대한소화기내시경학회 1998 Clinical Endoscopy Vol.18 No.1

A primary duodenal carcinoid tumor causing carcinoid syndrome is rare. In case of accompanying carcinoid syndrome in a primary duodenal carcinoid tumor, it mostly suggests massive liver metastasis. In rare case, venous drainage of carcinoid tumor and systemic venous drainage are directly connected without passing through the portal system. Therefore, it is rare and interesting case which a primary duodenal carcinoid tumor accompanies carcinoid syndrome without liver metastasis. We experienced an occasion of a primary carcinoid tumor located in duodenal bulb in a 56 year-old woman. This patient came to our hospital because of intermittent diarrhea, epigastric pain and facial flushing. And it was surely diagnosed as carcinoid tumor by gastrointestinal endoscopic biopsy. She was hospitalized for surgery and we were able to confirm that carcinoid syndrome was accompanied through biochemical test. However, metastatic lesion was not found at liver, small and large intestine. We report this case with reference to documents due to rarity.

전력선 통신 시스템의 입력 임피던스 계산

천동완(Dong wan Chun),이진택(Jin taek Lee),박영진(Young jin Park),김관호(Kwan ho Kim),신철재(Chull chai Shin) 대한두경부종양학회 2000 대한두경부 종양학회지 Vol.16 No.2

본 논문에서는 중 전압 전력선을 이용한 전력선 통신대 LC) 네트워크의 입력임피던스를 계산하였다. 먼저 전송 선로 모델을 이용하여 전력선 통신 네트워크의 입출력 단 모델을 제시하였으며, 여기에 전력선의 방사성 손실, 도체손실, 유전체 손실 등에 의한 감쇠상수를 적용시켜 임피던스를 계산하였다 계산결과 방사성 손실에 의한 강쇠 가 가장 크게 나타났으며, 전력선의 특정임피던스가 매우커서 입력 단에서의 반사가 심하기 때문에 입력임피던스 가 일정한 주기를 가지는 정재파 형태로 나타남을 알 수 있었다 또한 입력임피던스의 주기는 동축선로의 길이에 주로 의존하고, 크기는 주로 전력선의 특성임피던스 및 손실에 의존하였다 실제 측정결과 계산 치와 측정치가 매 우 유사함을 알 수 있었다. In this paper, we calculated the input impedance of the power line communication(PLC) networks using medium voltage power line. First of all, we proposed input and output teoninal model of PLC network, and calculated the input impedance applying the attenuation constants by radiation loss, conductor loss, dielectric loss. From the calculation result, we knew that the attenuation by radiation loss was largest, and the input impedance appears like a standing wave fonn with a fixed cycle because the high reflection at the input terminal for the characteristic impedance of the power line is very large. And also the cycle of input impedance depends on the coaxial cable length, and the amplitude depends on the characteristic impedance of power line and losses. From the measurement result, calculated result was very similar to the measured result.

등각사상 법을 이용한 접지 면에 어퍼처를 갖는 차폐된 마이크로스트립 선로 해석

천동완,이진택,김원기,신철재,Chun Dong-Wan,Lee Jin-Taek,Kim Won-Ki,Shin Chull-Chai 한국전자파학회 2004 한국전자파학회논문지 Vol.15 No.10

In this paper, we proposed the method of the characteristic impedance and effective dielectric constant calculations of the shielded microstrip line with ground aperture using conformal mapping method. This method has advantages that can calculate the transmission parameters without using any other numerical method because present the closed form equations. First of all, we supposed the signal propagate with the microstrip mode(Quasi-TEM) and calculated the capacitance divide by three sections and calculated the characteristic impedance and effective dielectric constant using calculated capacitances. From the HFSS simulation result, calculated result was very similar to the simulation result within the five percent error range. 본 논문에서는 등각사상 법을 이용해 접지 면에 어퍼처를 갖는 차폐된 마이크로스트립 선로의 특성임피던스 및 유효 유전 상수 등을 계산하는 방법을 제안하였다. 이 방법은 닫힌 형태의 공식을 제시하기 때문에 따로 어떠한 수치해석 방법을 쓰지 않고도 선로 파라미터들을 계산할 수 있다는 장점이 있다. 먼저 신호가 마이크로스트립 모드(Quasi-TEM)로 진행한다고 가정하고 차폐된 선로를 세 부분으로 나누어 정전 용량을 계산하고 계산된 부분별 정전 용량들을 이용해 임피던스 및 유효 유전상수를 계산하였다. HFSS 시뮬레이션 결과, 계산 결과가 시뮬레이션 결과와 오차범위 $5\%$ 이내로 거의 일치함을 알 수 있었다.

Calibration of HEPD on KOMPSAT-1 Using the KCCH Cyclotron

Young Hoon Shin,Jin Geun Rhee,Kyoung Wook Min,Chun Sik Lee,Ju Hahn Lee,Young Kwan Kwon,Jong Chan Kim,Jang Ho Ha,Se Hwan Park,Chang Hack Lee,H. S. Park,Young Kyun Kim,Jong Seo Chai 大韓遠隔探査學會 1999 大韓遠隔探査學會誌 Vol.15 No.4

Space Physics Sensor (SPS) on-board the KOMPSAT-1 consists of the High Energy Particle Detector (HEPD) and the lonospheric Measurement Sensor (IMS). The HEPD is to characterize the low altitude high energy particle environment and the effects on the microelectronics due to these high energy particles. It is composed of four sensors: Proton and Electron Spectrometer(PES), Linear Energy Transfer Spectrometer (LET), Total Dose Monitor (TDM), and Single Event Monitor (SEM). 35 MeV proton beam from the medical KCCH cyclotron, at Korea Cancer Center Hospital in Seoul, is used to calibrate the PES. Primary proton beam of 35MeV scattered by polypropylene target is converted to various energy protons according to the elastic collision kinematics. In this calibration, the threshold level of the proton in the PES can be determined and the energy ranges of PES channels are also calibrated.

Calibration of HEPD on KOMPSAT-1 Using the KCCH Cyclotron

Shin, Young-Hoon,Rhee, Jin-Geun,Min, Kyoung-Wook,Lee, Chun-Sik,Lee, Ju-Hahn,Kwon, Young-Kwan,Kim, Jong-Chan,Ha, Jang-Ho,Park, Se-Hwan,Lee, Chang-Hack,Park, H.S.,Kim, Young-Kyun,Chai, Jong-Seo,Kim, Yu- The Korean Society of Remote Sensing 1999 大韓遠隔探査學會誌 Vol.15 No.4

Space Physics Sensor (SPS) on-board the KOMPSAT-1 consists of the High Energy Particle Detector (HEPD) and the Ionospheric Measurement Sensor (IMS). The HEPD is to characterize the low altitude high energy particle environment and the effects on the microelectronics due to these high energy particles. It is composed of four sensors: Proton and Electron Spectrometer(PES), Linear Energy Transfer Spectrometer (LET), Total Dose Monitor (TDM), and Single Event Monitor (SEM). 35 MeV proton beam from the medical KCCH cyclotron, at Korea Cancer Center Hospital in Seoul, is used to calibrate the PES. Primary proton beam of 35MeV scattered by polypropylene target is converted to various energy protons according to the elastic collision kinematics. In this calibration, the threshold level of the proton in the PES can be determined and the energy ranges of PES channels are also calibrated.