인삼재배에 알맞은 토양관리

정환성 충남대학교 농업생명과학대학 2005 논문집 Vol.- No.12

하나로 연구용 원자로 03 - 중성자 이용해 물질 분석.방사성동위원소 등 생산

정환성,Jeong, Hwan-Seong 한국과학기술단체총연합회 2011 과학과 기술 Vol.511 No.-

협대역 이터븀 첨가 편광유지 광섬유 증폭기를 이용한 고품질 2 kW급 파장제어 빔 결합 레이저

정환성,이광현,이준수,김동준,이정환,조민식 한국광학회 2020 한국광학회지 Vol.31 No.5

In this paper, we have experimentally demonstrated a 2-kW-class spectrally-beam-combined laser with high beam quality, using narrow-linewidth ytterbium-doped polarization-maintaining fiber amplifiers. Five fiber amplifiers with different center wavelengths were implemented for the spectrally-beam-combined laser. The center wavelengths of the five amplifiers were 1062, 1063, 1064, 1065, and 1066 nm, respectively. A phase-modulated laser diode was used as a seed source for each amplifier. The seed sources were modulated by filtered pseudorandom-bit-sequence (PRBS) signals 5 GHz in linewidth. The polarization-maintaining large-mode-area fiber with a core size of 30 µm was used as a delivery fiber to mitigate the stimulated Brillouin scattering (SBS) effect. The laser beams from five amplifiers were spectrally combined by a multilayer dielectric diffraction grating. The maximum output power and beam quality M 2 of the combined laser were measured to be 2.3 kW and 1.74, respectively.

신규 실험설비 운전으로 인한 하나로 연구용 원자로의 운영 신뢰도 변화 분석

정환성(Hoan Sung Jung),임인철(In Cheol Lim) 한국신뢰성학회 2010 신뢰성응용연구 Vol.10 No.1

The HANARO nuclear research reactor had been operated successfully and smoothly up to the year 2008 since its first year of instability in year 1995 just after the completion of construction. But the reliability of the reactor has been degraded from the year 2009 due to new experimental facilities such as Feul Test Loop(FTL) and Cold Neutron Source(CNS) which were installed in the HANARO plant. It turned out that these new facilities contributed unexpected stoppage of the plant. This paper describes causes of stoppage and suggestions to improve the reliability of the plant.

섬유성 골 이형성증에서 시행한 골 이식술의 결과 분석

정원주,김태성,조환성,윤종필,박일형,Jeong, Won-Ju,Kim, Tae-Seong,Cho, Hwan-Seong,Yoon, Jong-Pil,Park, Il-Hyung 대한근골격종양학회 2014 대한골관절종양학회지 Vol.20 No.2

목적: 섬유성 골 이형성증은 신호전달 G 단백의 alpha 소단위체 유전자 변이에 따른 양성 골격계 질환으로 다양한 임상적 양상을 보인다. 기능적 장애, 구조적 변형를 방지하기 위해 제한적으로 수술을 시행하게 되는데 종양소파술 후 발생한 공동을 메우는 골 이식술이 시행된다. 이 연구에서는 본원에서 시행한 섬유성 골 이형성증 치료로서 자가 해면골 이식술을 시행한 경우와 자가 해면골과 동종골, 동종골만을 사용한 경우를 비교 분석하고자 한다. 대상 및 방법: 1997년4월부터 2013년 10월까지 본원에서 섬유성 골이형성증으로 진단된 58 명 중 수술 후 1년이상 추시 관찰이 가능했던 34명을 대상으로 하였다. 수술 시 평균 연령은 26.7세(범위, 2-57세)이었고, 남자는 13명, 여자는 21명이었다. 자가 골이식은 모두 장골에서 채취한 망상골을 이식하였고, 동종골은 골은행에서 기증받은 뼈를 이식용으로 재처리하여 이용하였다. 자가 해면골만 이식한 경우(I군)는 5예, 자가 해면골과 동종 골, 혹은 동종골만 이식한 경우(II군)가 29예였다. 재발, 이차적 변성 같은 합병증을 확인하기 위해, 주기적인 단순 방사선 촬영으로 관찰하였으며 각 군을 비교하였다. 결과: 섬유성 골이형성의 재발이 4예(11.4%)있었으며, 자가 해면골 이식술 시행한 군(I군; 1예 20%)과 자가해면골과 동종골, 혹은 동종골만을 이식한 경우(II군; 3예, 10.3%) 간의 재발율을 Kaplan-Meier 방법으로 분석한 결과 두군간의 차이가 없었다(p=0.554). 재발한 경우는 모두 소파술 및 자가골이식술을 다시 시행하였으며 재수술 후 재발은 없었다. 낭종 같은 이차적 변성이 확인된 경우가 1예, 병적 골절을 보인 경우 1예가 있었으나, 악성변화를 일으킨 경우는 없었다. 결론: 섬유성 골 이형성증 환자들에게 골이식을 시행한 경우, 자가 해면골 또는 동종 골 이식술을 시행한 양 군에서 재발,병적 골절 같은 합병증의 결과가 의미 있는 차이를 보이지 않았다. 따라서 종양의 부피가 작고 병변의 위치가 체중이 가하지는 부위가 아닐 경우에는 자가 해면골 이식 또한 좋은 방법으로 사료되며 이에 대한 연구가 필요하다. Purpose: Fibrous dysplasia is related to the mutation of gene encoding the alpha-subunit of a signal-transducing G-protein and has variable clinical course. Operation can be performed to prevent functional disorder or structural deformity. After curettage, autologous bone graft were used to fill the defects after curettage. The aim of this study is to compare the result of autogenous cancellous bone grafting and allogenic bone grafting for fibrous dysplasia. Materials and Methods: Among the patients who visit our hospital during the period of April, 1997 to October, 2013, we selected 34 patients who diagnosed fibrous dysplasia and visited our clinic over 1 year. There were 13 males and 21 females. Average age was 26.4 (range 2 to 57) years old. Autogenous bone graft (group I) in 5 cases, Non-autogenous bone graft (group II) in 30 cases. Iliac bone is used in all cases of autogenous bone graft. There were no significant difference in age, follow-up period, preoperational laboratory finding between two groups. Radiographic image was done to evaluate the recurrence of fibrous dysplasia or secondary degeneration. Results: There were four cases in recurrence (group I: 1 case, group II: 3 cases, p=0.554). In all recurrent cases, reoperations were done using curettage and autogenous iliac bone graft. There was no re-recurrence after reoperation. One case of secondary aneurysmal bone cyst was confirmed (group II) and 1 cases of pathologic fractures had developed (group I: 0 case, group II: 1 cases, p=0.559). No malignant change occurred. Conclusion: There were no significant difference between autogenous bone graft group and non-autogenous bone graft group. Our result suggested that autogenous bone graft seems to be good method to treat fibrous dysplasia, in the case of small volume of tumor lesion or non-weight bearing portion.

졸레드론산을 투여한 다발성 골수종 환자에서 발생한 비전형적 대퇴골 전자하 골절: 증례 보고

정원주,나상봉,조환성,김준우,박일형,Jeong, Won-Ju,Na, Sang-Bong,Cho, Hwan-Seong,Kim, Joon-Woo,Park, Il-Hyung 대한근골격종양학회 2012 대한골관절종양학회지 Vol.18 No.2

악성 종양 환자에게서 졸레드론산과 같은 비스포스포네이트를 예방적으로 투여받은 경우 이와 관련한 비전형적 대퇴골 골절의 발생 위험성은 아직까지 명확하게 밝혀진 바가 없으며, 국내에 지금까지 보고된 예가 매우 드물다. 본 증례는 다발성 골수종 환자에서 고농도 졸레드론산을 지속적으로 투여받았던 환자에서 큰 외상의 병력 없이 우측 대퇴골 전자하 부위의 비전형적 골절이 발생한 경우로 폐쇄적 정복술 및 골수강 내 금속정 내고정술로 치료한 경험을 보고하고자 한다. Little literature exists about the risk of atypical femoral fracture in patients received zoledronic acid for prevention of skeletal metastasis. We report an atypical subtrochanteric femoral fracture in a patient with multiple myeloma received zoledronic acid. The patient was treated by closed reduction and internal fixation with cephalomedullary nailing.

Single-walled carbon nanotubes on side polished fiber as a universal saturable absorber for various laser output states

고재권,정환성,최선영,Fabian Rotermund,염동일,김병윤 한국물리학회 2017 Current Applied Physics Vol.17 No.1

We demonstrated four different laser operational states in the same passive fiber ring laser cavity by controlling solely the polarization state in a saturable absorber. The demonstrated laser operational states were continuous wave, mode-locking, Q-switching, and Q-switched mode-locking. The saturable absorber was fabricated by spin-coating a single-walled carbon nanotubes (SWCNT)/polymer composite on a side polished fiber providing enhanced nonlinear interaction with the SWCNT. The wide tuning range of the saturable absorber allows the simple means to generate different forms of laser output from a single laser cavity.

단일 모드 2 kW급 고출력 광섬유 증폭기 내의 광섬유 용융 현상에 관한 연구

이준수,이광현,정환성,김동준,이정환,조민식 한국광학회 2020 한국광학회지 Vol.31 No.1

In this paper, we experimentally investigate the fiber fuse in single-mode 2-kW-class high-power fiber amplifiers, depending on the cooling method at the splicing point. We measured the temperature of the splicing point between the pump-signal combiner and gain fiber as a function of laser output power. The temperature of the splicing point increased from 20 to 32°C with a slope of 0.01°C/W, up to 1.2 kW of laser output power. At higher powers the temperature of the splicing point increased dramatically, with a slope of 0.08°C/W. After that, the fiber amplifier was destroyed during operation at 1.96 kW of output power by fiber fuse. The bullet shape, a common feature of fiber fuse, was observed in the damaged passive fiber core of the pump-signal combiner. Later, we adopted an improved water-cooled cold plate to increase the cooling efficiency at the splicing point, and investigated the laser output power. The temperature at the splicing point was 35.8°C with a temperature-rise slope of 0.007°C/W at the maximum output power of 2.05 kW. The beam quality M 2 was measured to be less than 1.3, and the output beam’s profile was a stable Gaussian shape. Finally, neither fiber fuse nor mode instability was observed in the fiber amplifier at the maximum output power of 2.05 kW.

Multiple osteoblastomas in a child with Cushing syndrome due to bilateral adrenal micronodular hyperplasias

Hyeoh Won Yu,조원임,정혜림,최근희,윤수미,조환성,신충호,양세원 대한소아내분비학회 2016 Annals of Pediatirc Endocrinology & Metabolism Vol.21 No.1

Adrenocorticotropin-independent adrenal hyperplasias are rare diseases, which are classified into macronodular (>1 cm) and micronodular (≤1 cm) hyperplasia. Micronodular adrenal hyperplasia is subdivided into primary pigmented adrenocortical disease and a limited or nonpigmented form ‘micronodular adrenocortical disease (MAD)’, although considerable morphological and genetic overlap is observed between the 2 groups. We present an unusual case of a 44-month-old girl who was diagnosed with Cushing syndrome due to MAD. She had presented with spotty pigmentation on her oral mucosa, lips and conjunctivae and was diagnosed with multiple bone tumors in her femur, pelvis and skull base at the age of 8 years. Her bone tumor biopsies were compatible with osteoblastoma. This case highlights the importance of verifying the clinicopathologic correlation in Cushing syndrome and careful follow-up and screening for associated diseases.

하나로 반사체계통 D2가스 관리 방법

최영산,김민진,김형규,배상훈,정환성 한국폐기물자원순환학회(구 한국폐기물학회) 2006 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2006 No.-