• Journal of Power Electronics
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• v.12 no.4
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• pp.632-642
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• 2012

This paper presents a filter analysis of conducted Electro-Magnetic Interference (EMI) in switching power converters (SPC) based on noise impedances. The EMI characteristics of SPC can be analytically deduced from a circuit theoretical viewpoint. The analytical noise model is investigated to get a full understanding of the EMI mechanism. It is shown that with suitable and justified model, filters pertinent to EMI noise is investigated. The EMI noise is identified by time domain measurements associated with an isolated half-bridge ac-dc converter. Practical filters like LC filter, ${\pi}$ filter and complete EMI filters are investigated. The proposed analysis and results can provide a guideline for improving the effectiveness of filtering schemes in SPC. Experimental results are also included to verify the validity of the proposed method. The results obtained satisfy the Federal Communications Commission (FCC) class A and class B regulations.

• JOURNAL OF ELECTRICAL WORLD
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• s.277
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• pp.69-77
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• 2000

최근 전력설비 운용상의 여러 가지 과제에 대한 유망한 해결책으로서 파워일렉트로닉스 기기를 사용한 FACTS(Flexible AC Transmission System)가 주목을 받고 있다. 그 중에서도 자려식 변환기를 사용한 FACTS기기는 계통의 유효전력$\cdot$무효전력을 계통의 상태에 의존하지 않고 자유롭게 제어할 수 있어, 계통운용의 유연성을 비약적으로 확대할 수 있는 가능성이 있다. 미쓰비시전기는 전력기기간 계통에서의 자려식 변환기 응용의 파이어니어로서 1991년 간사이전력(주) 태산개폐소에 80Mvar SVG(전지형 무효전력발생장치)를 납품하였으며 또한 자원에너지청의 ''연계강화기술개발'' 보조사업으로 도쿄전력(주)을 비롯하여 전력회사 각사, 전원개발(주)와 (재)전력중앙연구소의 지도 하에 3단자 BTB(Back to Back) 실증시스템용으로 세계 최초의 6인치 GTO(Gate Turn-off Thyristor)를 사용한 53MVA의 자려식 변환기를 제작납품하여 수백MVA 클래스의 자려식변환기 제작기술을 확립하였다. 또한 최근에는 동사가 개발한 신소자 GCT(Gate Commutated Turn-off Thyristor)는 지금까지 대용량 자려식 변환기의 커다란 과제였던 운전손실을 반감할 수 있을 것으로 기대되고 있다. 한편 배전 분야에서는 전압변동, 고조파, 순간전압강하 등의 과제가 증가하고 있어, 미쓰비시전기는 이에 응할 수 있는 파워일렉트로닉스 기기로서 콤팩트 SVG(Static Var Generator), SSTS(Solid-state Transfer Switch), 액티브필너를 다수 납품하여 전력품질문제 해결에 공헌하고 있다.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.384-384
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• 2012

PRAM switching device by using current pulse modulation was investigated to verify its possibility for 3D architecture. In this work, two phase change materials connected in series having a different crystallization temperature are used. Its structural for different phase change material was evaluated by electrical resistance. We confirmed that Germanium-Antimony-Tellurium (GST) alloy and Germanium- Copper-Tellurium (GCT) alloy material were selected according to crystallization temperature, ${\sim}180^{\circ}C$ for switching and ${\sim}240^{\circ}C$ for memory devices, respectively. From this research, it is expected that phase change switching device could have advantages of process in terms of material similarity and structural simplification.

• Archives of Pharmacal Research
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• v.13 no.4
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• pp.298-305
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• 1990

Based on equal number of cells, supplementation of 10$^{-6}$ M cadimium highly simulated the intracellular amylase. GCT, LDH as well as the glucose and erea content of E carotovora var, carotovaro cells. This was coupled with initiation of highly active GOT, CPK as well as accumulation of cholesterol in the cells. Lanthanum was less active and unable to initiate COT or CPK. Nickel was almost without effect though reduced LDH activity without initiating either enzyme or cholesterol production. Similar stiulations and/or initiations were observed, though to variable extents, when the same concentration of the three elements were supplied to E. carotovora var, citullis or E. toxica. The highest yield of amylase, GPT, GGT or glucose was obtained when E. carotovora var. carotovora was supplemented with Cd + Ni. The highest urea level was recorded in Erwinia carotovara var, cirullis, amended with Cd + La.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1556-1558
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• 2003

IGCT devices is a superior devices for power conversion purpose. The basic structure of the IGCT devices is same as that of GTO thyristor. This makes the blocking voltage higher and controllable on-state current higher. In this paper, we present static and dynamic characteristics of 4.5 kV PT-type IGCT devices as a function of minority carrier lifetime, n-base thickness and n-buffer thickness. We should choose proper structural parameters for good electrical characteristics of GCT devices.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.11a
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• pp.526-528
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• 2013

최근 실내 측위 기술을 이용한 다양한 서비스 제공을 위해 많은 위치 인식 기법이 연구되고 있다. 기존의 실내 위치 인식 기법은 사전에 획득한 맵 정보나 미리 구축한 기반 시설이 필요하거나, 추가 장비를 착용 및 부착해야 하는 단점이 있었다. 이에 본 논문에서는 스마트폰 내부센서를 이용하여 실내에서 사용자의 위치를 측정하는 시스템을 제안하였다. 제안한 시스템은 가속도 센서를 이용하여 이동여부를 파악하고, 사용자의 평균적인 이동속도와 방향센서를 이용하여 획득한 이동방향을 이용하여 위치를 추정한다. 제안한 시스템을 안드로이드 스마트폰에 구현하여 실험한 결과 약 ${\pm}75cm$ 이내의 오차에서 위치 인식이 가능함을 확인하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.520-522
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• 2022

의료 인공지능은 특정 진단에서 높은 정확도를 보이지만 모델의 신뢰성 문제로 인해 활발하게 쓰이지 못하고 있다. 이에 따라 인공지능 모델의 진단에 대한 원인 설명의 필요성이 대두되었고 설명가능한 의료 인공지능에 관한 연구가 활발히 진행되고 있다. 하지만 MRI 등 의료 영상 인공지능 분야에서 주로 진행되고 있으며, 이미지 형태가 아닌 전자의무기록 데이터 (Electronic Health Record, EHR) 를 기반으로 한 모델의 설명가능성 연구는 EHR 데이터 자체의 복잡성 때문에 활발하게 진행 되지 않고 있다. 본 논문에서는 전자의무기록 데이터인 MIMIC-III (Medical Information Mart for Intensive Care) 를 전처리 및 그래프로 표현하고, GCT (Graph Convolutional Transformer) 모델을 학습시켰다. 학습 후, 어텐션 흐름 그래프를 시각화해서 모델의 예측에 대한 직관적인 설명을 제공한다.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.4
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• pp.205-209
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• 2008

Recently, Sun et al (2008) reported that the IL6R polymorphism is associated with schizophrenia. Therefore, to detect the association between polymorphisms of interleukin 31 receptor A (IL31RA) and schizophrenia, we genotyped 9 SNPs [rs9292101 (intron 1), rs1009639 (exon 2, Pr043Pro), rs2161582 (intron 2), rs68761890 (intron 5), rs16884629 (intron 6), rs11956465 (intron 12), rs12153724 (intron 12), and rs16884641 (intron 14)] using the Golden Gate assay on Illumina BeadStation 500 GX. Two hundred eighteen patients with schizophrenia and 379 normal subjects were recruited. Patients with schizophrenia were diagnosed according to DSM-IV, and control subjects without history of psychiatric disorders were selected. We used SNPStats, Haploview, HapAnalyzer, SNPAnalyzer, and Helixtree programs for the evaluation of genetic data. Of nine polymorphisms, three SNPs (rs9292101, rs1009639, and rs11956465) were associated with schizophrenia. The rs9292101 and rs11956465 showed significant associations with the risk of schizophrenia in the codominant [rs9292101, odds ratio (OR)=0.74, 95% confidence interval (CI)=0.58${\sim}$0.95, p=0.017] and recessive (rs11956465, OR=0.64, 95% CI=0.42${\sim}$0.96, p=0.034) models, respectively. The rs1009639 also was statistically related to schizophrenia in both codominant (OR=0.76, 95% CI=0.60${\sim}$0.97, p=0.025) and dominant (OR=0.66, 95% CI=0.44${\sim}$0.98, p=0.035) models. Two linkage disequilibrium (LD) blocks were made. In the analysis of haplotypes, a haplotype (GCT) in block 1 and a haplotype (CCACAG) in block 2 showed significant associations between schizophrenia and control groups (haplotype GCT, frequency=0.509, chi square=4.199, p=0.040; haplotype CCACAG, frequency=0.289, chi square=5.691, p=0.017). The results suggest that IL31RA may be associated with risk of schizophrenia in Korean population.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.1
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• pp.32-38
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• 1997

PURPOSE : For the reconstruction of large bone defect after tumor resection, it is possible to reuse the bone involved by tumor with some treatment to it. Several bone-reusing methods have been reported such as autoclaving, low-heat treatment(pasteurization) and intraoperative radiotherapy. We have used extracorporeally radiated autogenous bone graft for reconstruction after tumor resection, and analyzed the periods for junctional union, functional results and complications to know the indications of this method. METHODS : From Dec. 1993 to Sept. 1995, nine patients had taken autogenous bone graft with extracorporeal irradiation. Eight cases were osteosarcoma and 1 giant cell tumor. The graft sites were 5 in femur, 3 proximal tibia and 1 femur and tibia. Stage 3 was 1 case(GCT), Stage IIB 3 and Stage IIIB 5. After wide resection, surrounding soft tissue and intramedullary and extramedullary portion of the tumor were removed. Radiation was done in 5000cGy to the resected bone. Ender nails and bone cement were inserted and filled into the medulla to prevent fracture. RESULTS : Average follow-up period was 12.3(4 to 21) months. Average junctional union period in simple X-ray was 6.5 months in 4 cases. Average functional score following Enneking's criteria was 19(12-27). Complications were as follows ; condylar fractures and femur neck fracture in 4 cases, subluxation of the knee joint 3 and infection 1. Although local recurrence was detected in 1 case, the site of recurrence was not in the radiated bone but surrounding soft tissue. At final follow-up, no recurrence was found in one case(GCT), CDF 2, AWD 2, DOD 3, and died of chemotherapy related sepsis 1. CONCLUSIONS : Extracorporeally radiated bone autograft is considered to be a method for reconstruction of the large bone defect made by tumor resection, especially in the reconstruction around the joint.

• The Journal of the Korean bone and joint tumor society
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• v.16 no.2
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• pp.51-54
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• 2010

Purpose: This study was aimed to evaluate the recurrence rate of a giant cell tumor (GCT) of the bone. Materials and Methods: The medical records of fifty four patients who were diagnosed with a giant cell tumor of the bone between March 1980 and December 2008 were analysed retrospectively. Among 54 patients, 27 were men, remaining 27 were women with the mean age of 33.1 years (range, 13-67 years). The mean duration of follow-up was 67.1 months. Results: Twenty-one patients (38.9%) had a local recurrence. The mean time to recurrence was 21.5 months (range, 2-59 months). The local recurrence rate of the upper extremities was higher than that of lower extremities. According to Campanacci classification, patients with a grade I diseae had lower recurrence rate than those with grade II or III disease. There was no significant differences in the recurrence rates based on cryotherapy, the filling of bone cement or bone grafts and surgical margin. Conclusion: To prevent local recurrence of GCT of bone, curettage of the tumor and elimination of the remaining cells are more important than adjuvant therapy.