고압 커패시터의 고장 분석을 통한 신뢰도 예측

양석준,김진우,신승우,이희진,신승훈,유동수,장석원 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.6

본 논문은 고압 커패시터의 고장분석과 신뢰성 예측 결과를 다루고 있다. 부품의 수명과 고장률을 예측하기 위해서 두 가지 방법으로 고장 모드와 고장 메커니즘을 연구하였다. 에폭시 수지로 성형된 고압 커패시터가 절연내압 시험 하에서 저항이 제로로 되는 고장에 대하여, 근본원인 고장분석 체계를 효과적으로 수립함으로써 고장 메커니즘의 원인을 분석하였다. 특히 세라믹-에폭시 계면에서의 절연파괴 고장 현상이 강조되었으며, 본 연구에서 얻어진 결과의 타당성은 마그네트론에 장착된 고압 커패시터의 열사이클 시험 수행에 의한 가속시험 결과로부터 입증되었다. 시험 결과들은 결함이 있는 로트를 신속히 규명하고 B10수명을 결정하는데 유용하게 사용할 수 있다. 또한, 유전체의 절연파괴에 대해서 부하-강도 간섭모델을 이용하여 고장률을 예측하였다. This paper presents a result of failure analysis and reliability evaluation for high voltage ceramic capacitors. The failure modes and failure mechanisms were studied in two ways in order to estimate component life and failure rate. The causes of failure mechanisms for zero resistance phenomena under withstanding voltage test in high voltage ceramic capacitors molded by epoxy resin were studied y establishing an effective root cause failure analysis. Particular emphasis was placed on breakdown phenomena at the ceramic-epoxy interface. The validity of the results in this study was confirmed by the results of accelerated testing. Thermal cycling test for high voltage ceramic capacitor mounted on a magnetron were implemented. Delamination between ceramic and epoxy, which might cause electrical short in underlying circuitry, can occur during curing or thermal cycle. The results can be conveniently used to quickly identify defective lots, determine B10 life estimation each lot at the level of inspection, and detect major changes in the vendors processes. Also, thd condition for dielectric breakdown was investigated for the estimation of failure rate with load-strength interference model.

Escherichia coli 패혈증 환자에 합병된 대칭적 하지 말단 괴사증 1예

남해성,유진홍,권순석,민준기,조현선,박민경,심병주,남유정,이지인,김진수,길욱현,조근종,신완식 대한감염학회 2005 감염과 화학요법 Vol.37 No.6

We have encountered a rare case of symmetrical peripheral gangrene complicating Escherichia coli sepsis in a 47-years-old male. He was successfully treated with antibiotics, anticoagulants, and vasodilator. To our knowledge, this is the first report on symmetrical peripheral gangrene complicating E. coli sepsis in Korea.

Delayed skin discoloration spreading in the direction of gravity after injection of hyaluronic acid dermal fillers in both nasolabial folds

Jun Ki Hong,Sun Hye Shin,Seog Kyun Mun,김범준 대한의학레이저학회 2022 MEDICAL LASERS Vol.11 No.3

Hyaluronic acid (HA) is the most commonly used filler biomaterial worldwide because of its safety, longevity, lack of immunogenicity, and biodegradability. In addition, HA is not specific to any organ or species, and there is a relatively low risk of an allergic or immunogenic reaction at the injection site. On the other hand, skin discoloration after a HA filler injection can increase for three reasons, including the Tyndall effect, neovascularization, and hyperpigmentation. This paper presents a case of skin discoloration after an injection of HA filler in the nasolabial fold with an unusual progress pattern.

유제품으로부터 Bifidobacteria의 선발 및 계수를 위한 선택배지

신명수,이정준,서인영,나석환,백영진 한국산업미생물학회 1994 한국미생물·생명공학회지 Vol.22 No.2

유제품에서 다른 유산균들과 혼합하여 사용되고 있는 bifidobacteria를 선발하고 계수하기 위하여 두가지 선택배지를 제조하였다. 하나는, phage의 숙주에 대한 감염 특이성을 이용한 것으로서 bifidobacteria와 혼합되어 있는 다른 유산균을 숙주로 하는 phage를 배지에 첨가하여 숙주 유산균을 용균시킴으로써 bifidobacteria에 대한 선택 배지로 사용하는 것이다. 즉, bifidobacteria와 L. casei HY 2782가 혼합된 유제품에서, L. casei HY 2782를 숙주로 하는 J1 phage를 첨가한 BL 배지를 사용하여 bifidobacteria를 계수한 결과, 완전하게 bifidobacteria만을 계수할 수 있었다. 따라서 항생제를 함유하는 선택배지가 아닌 새로운 선택배지로서 그 응용가능성을 제시하였다. 둘째로는 항생제 Tetracycline(1 ㎍/㎖)을 첨가한 선택배지로서 상업적으로 사용되는 bifidobacteria 균주의 성장에는 영향을 주지 않는 반면, Str. salivarius subsp. thermophilus, L. acidophilus, 그리고 L. casei 등의 성장은 억제하였다. 이러한 결과 tetracycline을 사용한 선택배지는 다른 항생제 배지들보다 유제품에 있는 bifidobacteria의 생균수를 정확히 표현해 주었다. Phage utilizing medium and BL agar supplemented with antibiotic Tc(tetracycline) were developed as selective media for the isolation and counting of bifidobacteria in dairy products. The former was based on the host specificity of phage. When bifidobacteria and Lactobacillus casei HY 2782 were mixed together in dairy product, L. casei HY 2782 was lysed by J1 phage which has host specificity to L. casei HY 2782 whereas bifidobacteria grew well on the selective medium added with J1 phage. The latter was found to inhibit the growth of S. salivarius subsp. thermophilus, L. acidophilus, and L. casei, but commercial bifidobacteria grew well in Tc-containing BL agar.

Effect of Animal Condition and Fluvoxamine on the Result of [$^{18}F$]N-3-Fluoropropyl-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-iodophenyl) Nortropane ([$^{18}F$]FP-CIT) PET Study in Mice

Shin, Kwang-Ho,Park, Su-A,Kim, Seog-Young,Lee, Sang-Ju,Oh, Seung-Jun,Kim, Jae-Seung The Korea Society of Nuclear Medicine 2012 핵의학 분자영상 Vol.46 No.1

Purpose : PET (positron emission tomography) is a noninvasive imaging technique, visualizing biological aspects in vivo. In animal models, the result of PET study can be affected more prominently than in humans by the animal conditions or drug pretreatment. We assessed the effects of anesthesia, body temperature, and pretreatment with selective serotonin reuptake inhibitor on the results of [$^{18}F$]N-3-fluoropropyl-$2{\beta}$-carbomethoxy-$3{\beta}$-(4-iodophenyl) nortropane ([$^{18}F$]FP-CIT) PET in mice. Methods : [$^{18}F$]FP-CIT PET of C57BL/6 mice was performed in three different conditions: (1) anesthesia (isoflurane) with active warming ($38^{\circ}C$) as a reference; (2) no anesthesia or warming; (3) anesthesia without warming at room temperature. Additional groups of mice pretreated with escalating doses of fluvoxamine (5, 20, 40, 80 mg/kg) were imaged in condition (1). The time activity curve and standardized uptake value of the striatum, cerebral cortex, and bone were compared among these conditions. Results : In all conditions, radioactivities of the striatum and cortex tended to form a plateau after rapid uptake and washout, but that of bone tended to increase gradually. When anesthetized without any warming, all the mice developed hypothermia and showed reduced bone uptake with slightly increased striatal and cortical uptakes compared to the reference condition. In conditions without anesthesia, striatal and cortical uptakes were reduced, whereas the bone uptake showed no change. Pretreatment with fluvoxamine increased the striatal uptake and striatal specific to cortical non-specific uptake ratio, whereas the bone uptake was reduced. Conclusion : Anesthesia, body temperature, and fluvoxamine affect the result of [$^{18}F$]FP-CIT PET in mice by altering striatal and bone uptakes.

Stereoselective Reduction of Methyl Vinyl Ketone Dimer

Jun, Jong-Gab,Shin, Dong-Gyun,Lee, Chang-Kiu,Sin, Kwan-Seog Korean Chemical Society 1990 Bulletin of the Korean Chemical Society Vol.11 No.4

The stereoselectivity of the reaction between methyl vinyl ketone dimer, which contains two possible sites of chelation, and zinc borohydride or diisobutylaluminum hydride has been studied in order to illuminate the factors involved in the high levels of asymmetric induction obtained in the bicyclic system. The conditions for the formation of the exo-5,7-dimethyl-6,8-dioxabicyclo[3.2.1]octane are DIBAH reduction of MVK dimer in ether at reflux followed by acidic cyclizatioan, and for the endo isomer are $Zn(BH_4)_2$ reduction with $ZnCl_2$ at $0^{\circ}C.$.

Tumors of the Pleura and Lung Developed 17 Years after Allogeneic Bone Marrow Transplantation for Childhood Acute Myelomonocytic Leukemia: Synovial Sarcoma Mimicking Malignant Mesothelioma

Jun Ah Lee,Bin Cho,Sun Ah Shin,Seog Yun Park,Meerim Park,Hyeon Jin Park 대한소아혈액종양학회 2021 Clinical Pediatric Hematology-Oncology Vol.28 No.1

Synovial sarcoma occurring in the pleura and lung is extremely rare. We report a case of pleuropulmonary synovial sarcoma as a second malignant neoplasm. The patient had been diagnosed with acute myelomonocytic leukemia at 5 years of age, and received matched sibling donor allogeneic bone marrow transplantation, with total body i rradiation and cyclophosphamide conditioning. At 22 years of age, he complained of worsening chest discomfort and exertional dyspnea. Chest CT revealed a huge mass in the right middle lobe, pleura, and diaphragm. The patient was initially diagnosed as sarcomatoid malignant mesothelioma, without any environmental or occupational a sbestos exposure. Five months later, the patient p resented with soft tissue metastasis and underwent needle biopsy. Pathological examination including SYT-SSX RT-PCR revealed synovial sarcoma, which led to a review of the original tumor findings and confirmed the diagnosis of pleuropulmonary synovial sarcoma. To the best of our knowledge, our patient is the first case of pleuropulmonary synovial sarcoma developed after allogeneic hematopoietic stem cell transplantation.

Trichoblastic fibroma with connection to the epidermis

( Shin Taek Oh ),( Jong Gap Park ),( Seog Jun Ha ),( Hyun Jeong Lee ),( Seok Jin Kang ),( Jin Wou Kim ) 대한피부과학회 1998 초록집 Vol.36 No.20

Genetic Variation in PSCA is Associated with Bladder Cancer Susceptibility in a Korean Population

Lee, Jun-Ho,Song, Hye-Rim,Kim, Hee Nam,Kweon, Sun-Seog,Yun, Yong-Woon,Choi, Jin-Su,Jung, Seung-Il,Kwon, Dong Deuk,Kim, Soo Hyun,Choi, Yoo-Duk,Shin, Min-Ho Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Background: Genetic factors play important roles in the pathogenesis of human cancer. A recent genome wide association study (GWAS) identified an association between the rs2294008 polymorphism of the prostate stem cell antigen (PSCA) gene and bladder cancer risk in Caucasians. The aim of this study was to determine whether the rs2294008 polymorphism is similarly associated with bladder cancer susceptibility in a Korean population. Materials and Methods: We conducted a case-control study of 411 bladder cancer patients and 1,700 controls. Results: The frequencies of the CC, CT, and TT genotypes of the rs2294008 polymorphism were 16.9, 54.0, and 28.8% in bladder cancer patients and 24.4, 48.1, and 27.5% in controls, respectively. We found that the combined CT/TT genotypes were associated with a significantly increased risk of bladder cancer (OR CT/TT =1.58, 95% CI= 1.15-2.17), compared with the CC genotype. Smoking habits, tumor grade and tumor stage did not modify the association between rs2294008 and the risk of bladder cancer. Conclusions: Our study showed that the rs2294008 polymorphism in the PSCA gene is associated with the risk of bladder cancer in a Korean population, providing evidence that it may contribute to bladder carcinogenesis regardless of ethnicity.

Deep neural networks perform equally and superiorly to dermatologists in onychomycosis diagnosis

( Seung Seog Han ),( Ik Jun Moon ),( Woohyung Lim ),( Gyeong Hun Park ),( Myoung Shin Kim ),( Jung Im Na ),( Sung Eun Chang ) 대한피부과학회 2017 대한피부과학회 학술발표대회집 Vol.69 No.2

Background: Although there have been reports of the successful diagnosis of skin disorders using deep learning, unrealistically large clinical image datasets are required for artificial intelligence (AI) training. Objectives: We created datasets of standardized nail images using region-based convolutional neural network (R-CNN) trained to distinguish the nail from the background. Methods: We used R-CNN to generate training datasets of 49,567 images, which we then used to fine-tune the ResNet-152 and VGG-19 models. The validation datasets comprised 100 and 194 images from Inje University (B1 and B2 datasets, respectively), 125 images from Hallym University (C dataset), and 939 images from Seoul National University (D dataset). Results: AI’s results showed test sensitivity/specificity/ area under the curve of (96.0 / 94.7 / 0.98), (82.7 / 96.7 / 0.95), (92.3 / 79.3 / 0.93), (87.7 / 69.3 / 0.82) for the B1, B2, C, and D datasets. For the B1 and C datasets, the AI’s Youden index was significantly (p = 0.01) higher than that of dermatologists. Conclusion: By training with a dataset comprising 49,567 images, we achieved a diagnostic accuracy for onychomycosis superior to that of most dermatologists who participated in this study.