Ni 분말 초내열합금 고온변형특성과 항온단조 공정기술 연구

전찬,배병범,윤은유,이영선,김동훈,홍성석,김홍규,윤존도 한국소성가공학회 2016 한국소성가공학회 학술대회 논문집 Vol.2016 No.4

토피라메이트에 의한 급성폐쇄각녹내장

전찬,기창원,Chan Jeon,Chang-Won Kee 대한안과학회 2005 대한안과학회지 Vol.46 No.11

Purpose: We describe 2 cases of bilateral acute angle-closure glaucoma associated with topiramate, a drug that has recently been prescribed for epilepsy or weight reduction. Methods: A 51-year-old man and a 27-year-old woman, previously devoid of ocular problems, visited the emergency room with blurry vision after taking topiramate for epilepsy and weight reduction, respectively. Thorough medical history taking and ocular examinations including ultrasound biomicroscopy were performed. Results: Ultrasound biomicroscopy revealed supraciliary choroidal effusion causing forward displacement of the lens-iris diaphragm, which resulted in myopia, anterior chamber shallowing, and increased intraocular pressure by angle-closure. Discontinuation of topiramate and the administration of cycloplegics, steroids and pressure-lowering agents led to the resolution of the symptoms. Conclusions: An idiosyncratic reaction of topiramate may produce supraciliary choroidal effusion and ciliary body edema, resulting in anterior displacement of lens-iris diaphragm, increased myopia and acute angle-closure glaucoma. Thorough medical history taking and ocular examinations are necessary to rule out the drug-induced acute angle-closure glaucoma.

Clinical Profile and Visual Outcomes after Treatment in Patients with Dysthyroid Optic Neuropathy

전찬,신재호,우경인,김윤덕 대한안과학회 2012 Korean Journal of Ophthalmology Vol.26 No.2

Purpose: To report the clinical data and visual outcomes after treatment of patients with dysthyroid optic neuropathy (DON). Methods: We retrospectively reviewed the medical records and orbital images of 40 patients (65 eyes) with DON and analyzed the visual outcomes after treatment with intravenous steroids pulse therapy, radiotherapy and orbital decompression. Results: The study included 21 men and 19 women, with 10 (25%) being diabetic patients. Visual field test results revealed defects in 88.7% of DON eyes; afferent pupillary defects in 63.2%; reduced color vision in 78.5%; and abnormal visual evoked potentials in 84%. Orbital imaging showed moderate to severe apical crowding in 95% of the orbits and intracranial fat prolapse in 24.2%. Median best corrected visual acuity improved from 0.4 to 1.0 after one year of treatment (p < 0.001). We noted more improvement in vision with the use of decompressive surgery than with non-surgical methods (p < 0.05). Recurrences occurred in 7 patients who had not received orbital radiotherapy. Conclusions: Visual field defects and apical crowding seen on orbital imaging were the most sensitive indicators for the detection of DON. Treatment with intravenous steroids pulse therapy, radiotherapy and orbital decompression effectively improved visual outcomes in cases of DON.

다공성 폴리에틸렌/티타늄 삽입물을 이용한 안와골절의 치료

전찬,신재호,우경인,김윤덕 대한안과학회 2009 대한안과학회지 Vol.50 No.8

Purpose: We present our experience with porous polyethylene/titanium implants in large orbital fractures that are difficult to repair with conventional orbital implants. Methods: A retrospective analysis was performed on seven patients who underwent repair of orbital fractures using porous polyethylene/titanium implants from September 2005 to December 2007. Results: The average age of the seven patients was 33.3 years, including two males and five females. The mean follow-up period was 5.4 months. Six cases had combined medial and inferior wall fractures, and one case had a large inferior wall fracture. Fractures were all large enough to encompass over 50% of the associated walls. After surgery, ocular motility disturbance and diplopia improved significantly. Enophthalmos improved from a mean of 2.9 mm to 0.6 mm postoperatively. No complications occurred such as visual loss, implant exposure or migration, or orbital infection. Conclusions: Porous polyethylene/titanium implants are effective and safe for the repair of large orbital fractures without the help of microscrews or microplates. 목적: 일반적인 삽입물로는 교정이 어려운 거대 안와골절 수술에서 다공성 폴리에틸렌/티타늄 삽입물(porous polyethylene/titanium implant)을 이용한 안와골 재건술의 경험을 보고하고자 한다. 대상과 방법: 2005년 9월부터 2007년 12월까지 본원에서 다공성 폴리에틸렌/티타늄 삽입물을 이용하여 안와골절 수술을 받은 7명의 의무기록을 후향적으로 조사하였다. 결과: 남자 2명, 여자 5명, 나이는 평균 33.3세였고, 추적관찰 기간은 평균 5.4개월이었다. 하벽 및 내벽 골절이 6명, 하벽 단독 골절이 1명이었다. 모든 골절은 해당 벽의 50% 이상을 차지하는 거대 골절이었다. 모든 환자에서 수술 후 안구운동장애와 복시가 사라졌거나 현저히 감소하였다. 평균 안구함몰은 술 전 2.9 mm에서 술 후 0.6 mm로 호전되었다. 시력저하나 삽입물의 노출, 이탈, 감염 등의 합병증은 없었다. 결론: 다공성 폴리에틸렌/티타늄 삽입물은 복원이 어려운 거대 안와골절의 수술에 있어 microscrew나 microplate의 도움 없이도 효과적 이고 안정적으로 사용될 수 있는 삽입물이라고 생각한다.

니켈기 초내열합금 분말의 고용화 열처리 후 냉각속도에 따른 크리프특성 분석

전찬,이영선,배병범,김홍규,홍성석,김동훈,윤존도,윤은유,Jun, Chan,Lee, Youngseon,Bae, Byeong Beom,Kim, Hong-Kyu,Hong, Seong Suk,Kim, Donghoon,Yun, Jondo,Yoon, Eun Yoo 한국분말야금학회 2016 한국분말재료학회지 (KPMI) Vol.23 No.3

In this study, solid solution heat treatment of consolidated nickel-based superalloy powders is carried out by hot isotactic pressing. The effects of the cooling rate of salt quenching, and air cooling on the microstructures and the mechanical properties of the specimens are analyzed. The specimen that is air cooled shows the formation of serrated grain boundaries due to their obstruction by the carbide particles. Moreover, the specimen that is salt quenched shows higher strength than the one that is air cooled due to the presence of fine and close-packed tertiary gamma prime phase. The tensile elongation at high temperatures improves due to the presence of grain boundary serrations in the specimen that is air cooled. On the contrary, the specimen that is salt quenched and consists of unserrated grain boundaries shows better creep properties than the air cooled specimen with the serrated grain boundaries, due to the negative creep phenomenon.

속발성 거대망막낭 3예

전찬,조희윤,강세웅 대한안과학회 2005 대한안과학회지 Vol.46 No.4

Purpose: Giant retinal cyst is formed by a localized and circumscribed splitting of the retina into two layers. It may often be confused with retinal detachment. We describe three cases of giant retinal cysts associated with retinal detachment associated with uveitis, and proliferative diabetic retinopathy. Methods: A retrospective, observational case series. Results: Two cases of giant retinal cyst were associated with uveitis: one detected during pars plana vitrectomy for total retinal detachment associated with chronic uveitis, and the other detected after scleral buckling procedure for retinal detachment associated with pars planitis. These cysts completely disappeared following drainage of fluid and laser photocoagulation to the flattened cyst. A case of retinal cyst secondary to proliferative diabetic retinopathy and vitreous hemorrhage was observed to be free of complication and progression without any surgical intervention for 9 months. Conclusions: Giant retinal cyst may result from intraretinal degenerative change caused by retinal capillary ischemia, vitreous traction and intraretinal leakage from the neovascularization. The cyst is considered to be stable without treatment in some cases, and in others it may be resolved with pars plana vitrectomy, fluid drainage and laser photocoagulation.

6번 뇌신경마비의 원인과 자연 경과

전찬,사호석,오세열,Chan Jeon,Ho Seok Sa,Sei Yeul Oh 대한안과학회 2006 대한안과학회지 Vol.47 No.11

Purpose: To evaluate the causes and natural course of sixth nerve palsy. Methods: The records of 37 patients with the sixth nerve palsy were reviewed to analyze the age of onset, etiology, angle of deviation, natural course of the palsy, and percentage of intervention. Results: The mean age of onset was 38.3 (3~77) years old. Causes and associations were: head trauma (n=11, 30%), idiopathic cause (n=9, 24%), neoplasm (n=7, 19%), aneurysm (n=2, 5%), and others (n=8, 22%). Complete recovery was observed in 80% of patients with nonhemorrhagic trauma and 33.3% with hemorrhagic trauma; 78% of patients with idiopathic cause; and 42.9% of patients with neoplasm. Conclusions: Head trauma was the most common cause of the sixth nerve palsy. Spontaneous complete recovery was observed in 80% of nonhemorrhagic trauma and 78% of idiopathic cases.

다발형 폴리아미드섬유 보강 콘크리트의 휨거동에 관한 실험적 연구

전찬기,전중규 한국재난정보학회 2014 한국재난정보학회 논문집 Vol.10 No.1

Synthetic fiber reinforced concrete is applicable to many applications for construction material. In general, synthetic fibers have low tensile strength and elastic modulus, but they have many advantages such as high crack resistance, impact resistance, chemical resistance, flexural behavior and corrosion free in fiber reinforced concrete. Recently, fiber reinforced concrete with macro synthetic fibers has been used to improve performance of structures in tunnel shotcrete, precast segmental lining and bridge slab and precast concrete structures. This study investigated the influence of bundled type polyamide fiber reinforced concrete on the flexural behavior in accordance with ASTM C 1609 and KS F 2566 standards. 일반적으로 건설재료 용도로 많이 사용되고 있는 유기섬유 보강 콘크리트는 섬유 자체의 인장강도 및 탄성계수는 낮지만, 휨거동, 균열에 대한 저항성 및 충격저항성 등의 특성은 우수하며, 내화학성이 뛰어나고 부식의 우려가 없는 것으로 널리 알려져 있다. 최근 해외에서는 유기섬유 보강재를 터널 숏크리트와 프리캐스트 세그먼트 라이닝, 교량 슬래브 및 PC제품 분야에서 일부 활용되고 있으며, 그 종류 또한 다양하다. 본 연구에서는 다발형 폴리아미드섬유를 혼입한 콘크리트의 휨거동 특성을 ASTM C 1609 및 KS F 2566에 준하여 하중-처짐 관계를 도출하여 유기섬유 보강 콘크리트의 적용 가능성을 검토하였다.

베터리 셀별 충전 시스템의 성능 향상 방안에 관한 연구

전찬용,목형수 제어로봇시스템학회 2019 제어로봇시스템학회 국내학술대회 논문집 Vol.2019 No.5

의류브랜드의 프로야구 스폰서십활동이 브랜드태도 및 구매의도에 미치는 영향

전찬수(Jun, Chan-Soo),강준상(Kang, Jun-Sang) 한국사회체육학회 2016 한국사회체육학회지 Vol.0 No.63

The purpose of this study was to examine the influence of sponsorship activities by sports brands upon brand attitude and purchase intention in professional baseball league. For this study, 320 spectators from post-season were chosen as the sample through convenience sampling method. Frequency, Cronbach′s α and correlation analysis were conducted by using SPSS WIN Ver 21.0. CFA(Confirmatory Factor Analysis) and SEM(Structural Equation Modeling) were conducted in order to verify overall fit of the model and hypothesis by using AMOS 18.0. The results were as follows: First, communication and image improving activities have a positive effect on brand attitude. Second, communication and image improving activities have a positive effect on purchase intention. Third, brand attitude has a positive effect on purchase intention. Thirdly, job satisfaction has a positive effect on customer orientation.