Flexible Terahertz Carbon Fiber Polarizer

강승범,강승범,황지영,김원석,김지연 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Terahertz (THz) polarizers, which are commercially available, are made of uniformly and precisely arranged metallic wires. They are fragile, expensive, and highly dependent on the diameter and spacing of the metal wires. Herein, we report a low cost, mass-producible, and highly error-tolerant technology for fabricating flexible and robust THz polarizers with good performance. Carbon fiber-based THz polarizers are fabricated by hot-melt impregnation process and their performances are experimentally demonstrated. THz time-domain spectroscopy is carried out on both flat and curved configurations to measure THz responses of the fabricated THz carbon fiber polarizer (THz-CFP). The results show a high extinction ratio between 20 and 35 dB in the 0.2~1.3 THz range. The insertion losses are lower than 3 dB in the 0.2~1.3 THz range.

사회적 변화에 따라 정신질환자들의 피해망상 속에 나타난 박해자 유형변화

강승범,황인복,김한석,김승곤,김학렬,박상학,김상훈,황걸 朝鮮大學校 附設 醫學硏究所 2008 The Medical Journal of Chosun University Vol.33 No.3

Objective: The authors investigated the frequency of persecutors in persecutory delusions of the psychiatric patients who didn't undergo the arrest or traumatic injury, reside in Gwangju Jeonnam area, and were admitted to the hospital after the 5.18 prodemocracy movement in Gwangju in 1980 upward 10 years. Also this study investigated the frequency of the persecutors before and after the prodemocracy movement and in capital and Gwangju Jeonnam area. Subjects and Methods: Among the 896 patients who were admitted to department of psychiatry, Chosun University Hospital from Jan. 1. 1989 to Dec. 31. 1991, we choosed 144 patients with persecutory delusion who had lived in Gwangju Jeonnam area for 10 years after 5.18 prodemocracy movement as subjects. Persecutors were classified into 7 class: unspecified, family, neighbors, communist or spy, police or army or secret agent, impersonal, others. Results: 1) In our study, the frequency of persecutors was family, unspecified, neighbors, police or army or secret agent, impersonal, others, communist or spy in descending order. As compared to previous studies (1956-2003) including our study about frequency of persecutor at capital area and Gwangju Jeonnam area, and before and after 5.18 prodemocracy movement, 2) At capital area, in the early 1980s, police, family, neighbors, unspecified person was frequent in descending order. In the both of early 1970s, 1990s, neighbors, family, unspecified person, police was frequent in descending order. 3) At Gwangju Jeonnam area, in the early 1970s, family, unspecified person, neighbors, police was frequent in descending order. In the early 1990s, unspecified person and family, neighbors, police was frequent in descending order. 4) The police class was most frequent at capital area in the early 1980s. Conclusions: We suppose that class of persecutor in persecutory delusions of psychiatric patients are changing according to social change, and frequency of police class was decreasing in both of capital and Gwangju, Jeonnam area.

연령관련황반변성에 동반된 맥락막신생혈관의 유리체강내 라니비주맙 주입술 임상결과

강승범,조원경,노영정 대한안과학회 2009 대한안과학회지 Vol.50 No.5

Purpose: To report 1-year clinical changes in visual acuity (VA) after intravitreal ranibizumab therapy for choroidal neovascularization (CNV) due to age-related macular degeneration (AMD), and to determine differences in treatment effects according to the CNV subtype. Methods: Forty six patients (46 eyes) with subfoveal CNV were treated with intravitreal ranibizumab (0.5 mg) injections as needed. Visual acuity, fluorescein angiography, and macular OCT were examined after 12 months. The patients were divided into two groups: Classic CNV and occult CNV. The VA of the two groups was compared 12 months after the initial injections. Results: The average VA and mean central retinal thickness (CRT) before ranibizumab treatment was 1.011±0.408 logMAR and 335.3 μm, respectively, and the VA and mean CRT 12 months after the initial injections was 0.928±0.357 logMAR and 246.2 μm, respectively (p=0.042, p<0.001). Out of 46 eyes, 13 eyes (28.3%) had a VA that improved by more than 0.1 logMAR, 33 eyes (71.7%) had VA that changed less than 0.1 logMAR, and 40 eyes (86.6%) had a VA that changed by less than 0.3 logMAR. The VA improved to 0.084 logMAR in classic CNV (18 eyes) and to 0.081 logMAR in occult CNV (28 eyes) after 12 months, though the difference between groups was not significant (p=0.910). Conclusions: Intravitreal injection of ranibizumab is an effective treatment for patients with subfoveal CNV secondary to AMD to improve or stabilize VA, and the effect of treatment on VA is not significantly different according to the CNV subtype. 목적: 연령관련황반변성에서 발생한 중심와밑 맥락막신생혈관 환자를 대상으로 유리체강내 ranibizumab 주입술 시행 후 12개월째 시력 결과와 맥락막신생혈관 종류에 따른 치료효과에 차이가 있는지 알아보고자 하였다. 대상과 방법: 연령관련황반변성에서 발생한 중심와밑 맥락막신생혈관 환자 46명 46안을 대상으로 유리체강내 ranibizumab (0.5 mg) 주입술을 시행하였다. 12개월의 경과 관찰 동안 시력검사, 형광안저혈관조영술, 황반부 빛간섭단층촬영을 하였고, ranibizumab 재주입 술이 필요한 환자들은 재치료를 하면서 12개월간 시력변화를 알아보았다. 또한 전형맥락막신생혈관 군과 잠복맥락막신생혈관 군으로 나누어 12개월째 ranibizumab 치료에 따른 시력변화에 차이가 있는지 알아보았다. 결과: 유리체강내 ranibizumab 주입술 전 평균 logMAR 시력은 1.011±0.408, 평균 황반두께는 335.3 μm, 12개월 째 평균 logMAR 시력은 0.928±0.357, 평균 황반두께는 246.2 μm이었다 (p=0.042, p<0.001). 0.1 logMAR 이상의 시력호전은 13안(28.3%)에서 나타 났고, 시력이 호전되거나 0.1 logMAR 미만의 시력소실은 33안(71.7%)에서, 시력이 호전되거나 0.3 logMAR 미만의 시력소실은 40안 (86.9%)에서 나타났다. 12개월 경과 관찰 동안 전형맥락막신생혈관 군 18안에서는 평균 0.084 logMAR의 시력개선 효과가, 잠복맥락막 신생혈관군 28안에서는 평균 0.081 logMAR의 시력개선 효과가 되어 관찰되었으나 두 군 간의 차이는 없었다(p=0.910). 결론: 연령관련황반변성에서 발생한 중심와밑 맥락막신생혈관 치료에 ranibizumab 유리체강내 주입술은 시력을 보존하는데 유용하게 사용될 수 있는 치료법이며 맥락막신생혈관의 종류에 따라 치료효과에 차이가 나지 않는다.

활락단(活絡丹)이 항염(抗炎), 진통(鎭痛) 및 항혈전(抗血栓)에미치는 영향(影響)에 대(對)한 연구(硏究)

강승범,박종운,김종길,조남수,문병순,Kang, Seung-Bum,Park, Jong-Woon,Kim, Jong-Gil,Jo, Nam-Soo,Moon, Byung-Soon 대한한방내과학회 1999 大韓韓方內科學會誌 Vol.20 No.1

This study was designed to elucidate the anti-inflammatory, cardiovascular, anti-thrombotic, and analgesic effect of Whalrakdan. The anti-inflammatory effects was measured by the method of carrageenin induced edema, protein leakage test using CMC-pouch, and the effect of Whalrakdan on the cardiovascular system was observed by the change of flow rate of Ringer solution in the vascular system in the ear of rabbit. and the contraction and dilatation of rat tail artery. Death rate, platelet aggregation, plasma coagulation activity, antithrombin activity was observed for the measurement of the anti-thrombotic effect of Whalrakdan, and the analgesic effect was measured by the acetic acid method and hot plate method. The result was as follows: 1. After 2 or 3hour of Whalrakdan administration, carrageenin induced edema and CMC-pouch protein leakage was significantly decreased. 2. The slight anagesic effect of Whalrakdan extract was confirmed by the observation of writhing syndrome, paw licking time, and escape time. 3. The droplet of Ringer solution increased according to the increase of concentration of Whalrakdan extract, and the vasoconstriction decreased dependantly to the concentration of Whalrakdan extract. 4. The anti-thrombotic effect of Whalrakdan was observed by the decrease of death rate, the inhibition of platelet aggregation, and the increase of anti-thrombin activity.

이차성 삼차신경통에서 경피적 고주파 삼차신경절제술에 의한 동통조절 효과

강승범,손병철,김문찬,강준기,Kang, Seong-Buhm,Son, Byung-Chul,Kim, Moon-Chan,Kang, Joon-Ki 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.1

Objective : There are many treatment modalitis in management of idiopathic trigeminal neuralgia. In the secondary trigeminal neuralgia, there has been only sporadic reports of the etiology. Authors report the treatment result of secondary trigeminal neuralgia with percutaneous radiofrequency rhizotomy. Methods : During last ten years, 129 trigeminal neuralgias were treated by percutaneous radiofrequency(RF) rhizotomy by authors. Among them, nine patients were secondary trigeminal neuralgias. These patients refused treatment for the primary cause and only wanted pain control. The offending lesions were three arachnoid cysts, six tumors. The mean age was 47.8 years and the mean duration of follow-up was 6.2 years. The right V2,3 distribution was most prevalent area of pain. Authors used the conventional Hartel's anterior approach and straight electrode for RF lesion generation. Result : The early result was satisfactory. Eight of nine patients became free of pain and one patient needed minimal dose of carbamazepine. The overall pain control was 100%. There was no mortality or morbidity for initial RF rhizotomy. During follow-up, four patients showed recurrence of pain(44%). Among these, two underwent repeated RF rhizotomy and became free of pain. The other two were controlled with medical management. Conclusion : These results indicate that the percutaneous RF rhizotomy is effective means of pain control. Overall recurrence was somewhat higher than that of idiopathic trigeminal neuralgia. Even with recurrence, however, repeated RF rhizotomy seems to be effective method of control of pain in these cases.

Pr3+ 도핑된 셀레나이드 유리의 테라헤르츠 광학 특성

강승범,정동철,곽민환 한국전기전자재료학회 2017 전기전자재료학회논문지 Vol.30 No.11

Terahertz time-domain spectroscopy has been used to study the optical properties of Pr3+-doped selenideglasses. The complex refractive indexes of Pr3+-selenide glasses were measured in a frequency range from 0.3 to 1.5THz. The real and imaginary refractive indexes increased with increasing frequency and Pr3+ ion concentration. Theobtained result indicated that the phonon modes of the Pr3+-doped selenide glasses shift to lower frequencies with theconcentration of Pr3+ ions. The theory of far-infrared absorption in amorphous materials was used to analyze the results. The measured data showed that the disorder-induced terahertz absorption increased with increasing Pr3+ ion concentration. Pr3+ 도핑된 셀레나이드 유리의 광학 특성을 THz-TDS를 사용하여 THz 주파수 영역에서 관찰하였다. Pr3+ 도핑된 셀레나이드 유리의 복소 굴절률은 0.3 ~ 1.5 THz의 주파수 범위에서 얻었으며 Pr3+ 도핑된 Ge30As8Ga2Se60 유리의 리얼 및 이미지너리 굴절률은 주파수와 Pr3+ 농도가 증가함에 따라 증가됨을 알 수 있었다. 측정된 굴절률은 파수 범위 전반에 걸쳐 Sellmeier 방정식에 의한 값과 비교적 일치했다. THz 흡수가 Pr3+ 농도가 증가함에 따라 증가한다는 것을 보여준다. 높은 THz 굴절률을 갖는 유리에서도 THz 흡수가 더 높다는 것을 알 수 있었으며 이러한 결과는 Pr3+ 농도가 증가함에 따라 전하 변동 밀도가 증가한다는 것을 의미한다.

펌프광에 의해 유도되는 어븀첨가 광섬유의 굴절률 변화 및 분산특성 측정 ( Measurement of Pump Power Dependent Changes of Refractive Index and Dispersions in Er3 - Doped Fibers )

강승범,임기수,이학규,임동성,김경헌 대한전자공학회 1998 대한전자공학회 학술대회 Vol.1998 No.1

펌프광에 의해 유도되는 어븀첨가 광섬유의 굴절률 변화 및 분산특성 측정 ( Measurement of Pump Power Dependent Changes of Refractive Index and Dispersions in Er3+ - Doped Fibers )

강승범,임기수,이학규,임동성,김경헌 한국통신학회 1998 광전자공학회 학술회의 Vol.5 No.1

LT-GaAs 광전도 안테나 소자 기반의 T-ray 분광기

강승범,곽민환,김성일,정세영,류한철,강대원,이승환,최상국,백문철,강광용 한국진공학회 2008 한국진공학회 학술발표회초록집 Vol.2008 No.8

미국 내 한국이민자의 사회경제적 적응 과정

강승범,김갑성 한국지역학회 2012 지역연구 Vol.28 No.1

In this paper, we empirically investigate the socioeconomic adaptation process of Korean immigrants in United States by analyzing a series of population census data from 1980 to 2010, focusing on their employment, occupational attainment, earning attainment, and working status. Korean immigrants have shown the highest rate of self-employed among many kinds of immigrants since the revision of immigration law in 1965. We specifically pay attention to three effects; entry effects which mean there were differences of economic output between native American and immigrants when immigrants entered the U.S labor market, cohort effects which are changes of entry effects over time, and assimilation effects which show that the changes of gaps between natives and immigrants as staying period had become longer. At the time of entry, results show that Korean immigrants were less likely to be employed in high-level occupation, more likely to be trapped in self-employed job and to earn much less than the natives. As they stayed longer, the gaps of employment opportunity, occupational attainment and earning tended to decrease with different paces. Because new immigrants after 1990 fared better in terms of occupational attainment and were less self-employed compared to those who arrived earlier, we can find some evidence to suggest that the changing cohort quality had significant effect on immigrant society. 본 연구의 목적은 한국인 이민자가 미국노동시장에서 사회경제적으로 적응하는 과정을 1980년부터 2010년까지의 시간적 범위를 바탕으로 살펴보는데 있다. 본 연구에서는 미국 태생의 미국시민집단에 비해 한국이민자 집단이 노동시장에 진입했을 때 사회경제적 차이가 존재하는지, 이민기간이 길어짐에 따라 그 차이는 점차 감소하는지, 보다 최근에 미국으로 이민을 온 집단의 질적인 변화는 존재하는지를 중점적으로 살펴보았다. 이민자의 사회경제적 지위를 반영한 고용확률, 상위직종 종사비율, 자영업 종사비율, 소득의 차이를 각각 분석한 결과, 진입 초기에 노동시장에서의 미국 태생의 미국인 집단과의 격차는 분명히 존재했으며 이민기간이 길어짐에 상위직종에 종사할 확률과 소득의 차이가 점차 감소하는 것을 발견할 수 있었다. 자영업 종사확률은 10년의 이민기간이 지나면 오히려 증가하는 모습을 보여 노동시장의 경험을 바탕으로 종사상 형태의 전환을 시도하는 모습을 발견할 수 있었다. 이민자 집단의 질적 변화는 이민 초기에 보다 동등한 소득을 받으며 상위직종에 종사할 확률과 봉급을 받으며 종사할 확률이 점차 높아져 미국 노동시장에 필요한 능력을 이미 보유한 사람들의 이동이 최근에 주를 이루고 있음을 살펴볼 수 있었다.