• Bulletin of the Korean Chemical Society
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• 제34권6호
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• pp.1779-1782
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• 2013

N-type ZnO nanorods were grown on p-type porous silicon using a chemical bath deposition (CBD) method (p-n diode). The structure and geometry of the device were examined by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) while the optoelectronic properties were investigated by UV/Vis absorption spectrometry as well as photoluminescence and electroluminescence measurements. The field emission (FE) properties of the device were also measured and its turn-on field and current at 6 $V/{\mu}m$ were determined. In principle, the growth of ZnO nanorods on porous siicon for optoelectronic applications is possible.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1592-1593
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• 2011

전 세계적으로 전력사용량의 증가와 전력기술이 발전함에 따라 절연소재 또한 급속한 발전을 가져왔다. 특히 폴리머 애자는 경량성, 내오염성, 시공의 용이성 등과 같은 장점으로 오랫동안 사용해온 자기 애자를 대체하여 사용되고 있다. 최근 고효율 장거리 전력 송전이 가능한 HVDC 송전선로가 증가함에 따라 직류 절연물에 대한 연구가 활발히 이루어지고 있다. 본 연구에서는 두 종류의 실리콘 베이스와 첨가제 함량을 변화시킨 폴리머 시편의 직류 파괴전압 실험과 교류 파괴전압 실험을 실시하였다. 취득한 데이터를 Weibull 분포를 통해 분석 한 결과 직류 파괴전압이 교류 파괴전압에 비해 2~5배 높은 것으로 나타났다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2006년도 가을 학술발표논문집 Vol.33 No.2 (C)
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• pp.1-5
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• 2006

과거에 비해 최근에 비즈니스 프로세스가 다양해지고 복잡해짐에 따라 비즈니스 프로세스를 디자인할 때 발생할 수 있는 문제점이 점차 증가하고 있다. 그로인해 비즈니스 프로세스 검증의 중요성이 높아지고 있지만 많은 검증 방법이 제안되고 있지 않은 실정이다. 한편, 최근 BPMI에서 주도하는 BPMN(Business Process Modeling Notation)은 비즈니스 프로세스를 위한 표준화된 그래픽 표기법으로써 BPMN을 지원하는 디자인 툴을 이용하면 다양하고 복잡한 프로세스 환경을 일반화된 형태로 디자인하고 분석할 수 있다. 이 논문에서는 이러한 BPMN으로 디자인할 때 발생할 수 있는 문제점들을 효율적으로 검증할 수 있는 몇 가지 검증기법을 제시한다. 이로 인해 비즈니스 프로세스 실행 시 발생할 수 있 문제점들을 효율적으로 검증할 수 있는 몇 가지 검증기법을 제시한다. 이로 인해 비즈니스 프로세스 실행시 발생할 수 있는 에러들을 사전에 검증하여 예기치 못한 큰 비용을 줄일 수 있다.

• Journal of Korean Neurosurgical Society
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• 제30권5호
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• pp.657-661
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• 2001

Intracranial giant aneurysms have been known to cause clinical signs and symptoms, either by rupture, compression of surrounding structures, repeated minor leakage, or cerebral ischemia due to thromboembolism. A giant aneurysm which manifests only a seizure disorder comprises relatively few contributions. The authors present a case of a giant, unruptured aneurysm solely presenting with generalized tonic-clonic type seizure in a 43-year-old man. Brain computed tomogram(CT) and 3-D CT angiogram demonstrated a huge calcified aneurysm at the bifurcation of right middle cerebral artery. Complete neck clipping and aneurysmectomy followed by uneventful neurologic recovery.

• Journal of Korean Neurosurgical Society
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• 제58권2호
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• pp.159-162
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• 2015

Neurological deficits after brain surgery are not uncommon, and correct and prompt differential diagnosis is essential to initiate appropriate treatment. We describe a patient suffering from loss of consciousness due to hyperammonemia, following valproic acid treatment after surgery for an unruptured cerebral aneurysm. A 57-year-old female patient underwent successful aneurysmal neck clipping to correct an unruptured aneurysm. Her postoperative course was good, and she received anti-epileptic therapy (valproic acid) and a soft diet. Within a few days the patient experienced mental deterioration. Her serum valproic acid reached toxic levels (149.40 mg/L), and serum ammonia was fifteen times the upper normal limit (553 mmol/L; normal range, 9-33 mmol/L). After discontinuation of valproic acid and with conservative treatment, the patient recovered without any complications. Valproate-induced hyperammonemic encephalopathy is an unusual but serious neurosurgical complication, and should not be disregarded as a possible cause of neurological deficits after neurovascular surgery. Early diagnosis is crucial, as discontinuation of valproic acid therapy can prevent serious complications, including death.

• 한국물환경학회지
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• 제31권1호
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• pp.42-48
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• 2015

This study focused on effective decomposition methods for low concentrated organic compounds from the reuse of industrial wastewater, and confirmed the possibility through photocatalyst media. Photocatalyst immobilized media was developed to carry on this experiment which confirmed the removal possibility of low concentrated organic compounds. Considering the stability and efficiency of photocatalyst immobilization, inorganic support, hollow bead, and $TiO_2$ nano powder were used. As a result of the removal experiment, the removal efficiencies of acetonitrile, ethanol, IPA(Isopropyl alcohol), methanol were above 75% after 15 minutes while those of acetone, acetaldehyde, urea were 10%, 45%, 20%, respectively after 60 minutes. If further studies were made to increase the surface area of the photocatalyst immobilized media, the efficiency of the removal of low concentrated organic compounds can be improved and this solution can also be used in an actual treatment process.

• Journal of Chest Surgery
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• 제35권7호
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• pp.564-567
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• 2002

Primary malignant lymphoma of the lung is a very rare disease, which consists of 0.34% of entire malignant lymphoma. The majority are low-grade B-cell tumors, and because of their morphological peculiarities and overall excellent prognosis, many cases, like many other extranodal lymphomas, have been mislabelled as "pseudolymphomas" in the past. For these reasons their true incidence is difficult to estimate. An incidentally discovered mass in the right middle lobe of a 36-year-old woman was operated on November 9, 2001 at Hanyang University Hospital. A right upper lobectomy was done and the pathologic diagnosis of extranodal marginal zone B-cell lymphoma of MALT type was made.

• Journal of Korean Neurosurgical Society
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• 제30권10호
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• pp.1237-1240
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• 2001

Spontaneous herniation of the spinal cord is a very rare. It's clinical symptom presents with progressive myelopathy. A 42-year old male patient who presented the progressive left leg weakness and Brown-Seqaurd syndrome is presented. MRI showed a typical finding of dural defect and herniation of the cord on the level of T3-4. Repair of dural defect using an artificial dura and reposition of cord herniation were undertaken after three level laminectomies with SSEP monitoring. Postoperatively, symptoms were improved rapidly. In our knowledgement, this is first case being reported in Korea. This entity, although rare, should be considered in the differential diagnosis of myelopathy in the absence of a mass lesion.

• Nuclear Engineering and Technology
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• 제53권9호
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• pp.2909-2917
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• 2021

Following the launch of Rare Isotope Science Project in December 2011, a heavy ion accelerator complex in South Korea, named RAON, has since been designed. It includes a muon facility for muon spin rotation, relaxation, and resonance. The facility will be provided with 600 MeV and 100 kW (one-fourth of the maximum power) proton beam. In this study, the graphite target in RAON was designed to have a rotating disk shape and was cooled by radiative heat transfer. This cool-down process has the following advantages: a low-temperature gradient in the target and the absence of a liquid coolant cooling system. Monte Carlo simulations and ANSYS calculations were performed to optimize the target system in a thermally stable condition when the 100 kW proton beam collided with the target. A comparison between the simulation and experimental data was also included in the design process to obtain reliable results. The final design of the target system will be completed within 2020, and its manufacturing is in progress. The manufactured target system will be installed at the RAON in the Sindong area near Daejeon-city in 2021 to carry out verification experiments.

• Nuclear Engineering and Technology
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• 제52권12호
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• pp.2910-2917
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• 2020

Digital light processing three-dimensional (3D) printing technique is a powerful tool to rapidly manufacture plastic scintillators of almost any shape or geometric features. In our previous study, the main properties of light output and transmission were analyzed. However, a more detailed study of the other properties is required to develop 3D printed plastic scintillators with expectable and reproducible properties. The 3D printed plastic scintillator displayed an average decay time constants of 15.6 ns, intrinsic energy resolution of 13.2%, and intrinsic detection efficiency of 6.81% for 477 keV Compton electrons from the ¹³⁷Cs γ-ray source. The 3D printed plastic scintillator showed a similar decay time and intrinsic detection efficiency as that of a commercial plastic scintillator BC408. Furthermore, the presented estimates for the properties showed good agreement with the analyzed data.