Spark plasma sintering을 이용한 수분무 Al-Zn-Mg합금분말의 소결특성

김선미,김택수,김영도,김정곤,Kim, Sun-Mi,Kim, Taek-Soo,Kim, Young-Do,Kim, Jeong-Gon 한국분말야금학회 2009 한국분말재료학회지 (KPMI) Vol.16 No.1

In order to investigate the effect of rapid solidification on the microstructure and the mechanical properties of Al-Zn-Mg system alloys, water atomization was carried out, since the water atomization beared the highest solidification rate among the atomization processes. The as atomized alloy powders consisted of fine grains less than 4 ${\mu}m$ in diameter, and the second particles were not detected on XRD. The microstructure as solidified was maintained even after the spark plasma sintering at the heating rate of 50 K/min. On the other hand, lower rate of 20 K/min induced a formation of $MgZn_2$ particles, resulting in strengthening of the matrix. The density was almost constant at the temperature above 698K. The sintering temperature above 698K had no effect on the strength of the sintered materials.

전기화학적 제조를 통한 나노다공성 텅스텐 산화물 성장의 전열처리 영향

김선미,김경민,최진섭,Kim, Sun-Mi,Kim, Kyung-Min,Choi, Jin-Sub 한국전기화학회 2011 한국전기화학회지 Vol.14 No.3

본 연구에서는 텅스텐 금속박막을 $200^{\circ}C$에서부터 $600^{\circ}C$의 온도 구간에서 전열처리 (Preannealing) 한 후에, 빛의 조사 유무에 따라 양극산화를 진행하여 생성된 텅스텐 산화물의 표면과 두께에 대해 관찰하였다. 결과적으로 6시간의 동일한 반응시간 동안, $400^{\circ}C$에서 전열처리 한 후에 빛의 조사 없이 양극산화 하였을 때, $1.83{\mu}m$ 두께의 텅스텐 산화물을 제조할 수 있는 것을 발견하였다. 더욱이 전열처리를 하게 되면 더 두꺼운 산화물을 제조 할 수 있으나, 빛을 조사하게 되면 전열처리에 의해 생성된 산화물을 결정화시켜 오히려 산화물 성장에 방해가 되었다. 이러한 차이점에 대해 결정구조 및 메커니즘에 근거하여 설명하였다. We describe that the surface and thickness of nanoporous $WO_3$ fabricated by both light-induced and light-absent anodization are affected by pre-annealing process from $200^{\circ}C$ to $600^{\circ}C$. As a result, the nanoporous $WO_3$ with a thickness of $1.83{\mu}m$ can be achieved by anodization for 6 hours after pre-annealing at $400^{\circ}C$ without illumination of light. Moreover, the thickness of nanoporous $WO_3$ fabricated by pre-annealing is thicker than that of $WO_3$ prepared by non-annealing process. However, the light illumination during anodization leads to convert the crystalline structure obtained by pre-annealing, which interfere the growth of nanoporous $WO_3$. In this paper, we discuss about the growth mechanism of these different nanoporous $WO_3$ films.

Biological Activity of Tumor Necrosis Factor-α Secreted from Smooth Muscle Cell Overexpressing FADD

김선미,이경아,김관회,Kim, Sun-Mi,Lee, Kyeong-Ah,Kim, Koan-Hoi Korean Society of Life Science 2007 생명과학회지 Vol.17 No.1

세포 배양액에 tetracycline이 없는 경우 FADD를 발현하면서 사멸하는 평활근세포 (FADD-SMC)에서 분비하는 $TNF-\alpha$의 활성을 조사하였다. 배양액에 tetracycline이 없는 경우 FADD-SMC는 약 1000 pg/ml의 $TNF-\alpha$를 분비하였다. $TNF-\alpha$를 포함하는 배양액을 분리하고, 이 배양액을 정상세포에 처리한 결과 인산화한 p38 MAPK와 nuclear, factor, kappa B (NF-kB)의 활성이 증가하였다. 또한 이 배양액을 L929 세포에 처리하는 경우 세포독성이 발생하였다. NF-kB, p38 MAPK 그리고 L929 세포에 대찬 효과는 배양액에서 suluble TNF receptor를 이용하여 $TNF-\alpha$를 제거하는 경우 감소하였다. This study investigated biological activity of tumor necrosis factor $(TNF)-\alpha$ secreted from smooth muscle cell (SMC) destined for death by expressing Fas associated death domain containing protein (FADD) (FADD-SMC) when the cells are grown without tetracycline in culture medium. In the absence of tetracycline the FADD-SMC secreted approximately 1000 pg/ml $TNF-\alpha$, whereas hardly detectable amount of the cytokine existed in the presence of tetracycline. The culture medium collected from the FADD-SMC grown in the absence of tetracycline increased phosphorylated form of p38 MAPK and up-regulated nuclear factor kappa B (NF-kB). The medium collected without tetracycline also caused death of L929 cells. Depletion of $TNF-\alpha$ with the soluble TNF receptor (sTNFR) inhibited the phosphorylation of p38 MAPK, the up-regulation of NF-kB activity and the death activity of the medium collected from FADD-SMC in the absence of tetracycline. These results indicate that $TNF-\alpha$ secreted from SMC undergoing death is biologically active and can affect cellular function.

Characterization of Antibiotic Resistance Determinants in Oral Biofilms

김선미,Hyeong C. Kim,이석우 한국미생물학회 2011 The journal of microbiology Vol.49 No.4

Oral biofilms contain numerous antibiotic resistance determinants that can be transferred within or outside of the oral cavity. The aim of this study was to evaluate the prevalence and the relative level of antibiotic resistance determinants from oral biofilms. Oral biofilm samples that were collected from healthy subjects and periodontitis patients were subjected to qualitative and quantitative analyses for selected antibiotic resistance determinants using PCR. The prevalence of tet(Q), tet(M), cfxA, and blaTEM was very high both in the patient and the healthy subject group, with a tendency toward higher values in the patient group,with the exception of erm(F), which was more prevalent in the healthy group. The two extended spectrum β-lactam (ESBL) resistance determinants blaSHV and blaTEM showed a dramatic difference, as blaTEM was present in all of the samples and blaSHV was not found at all. The aacA-aphD, vanA, and mecA genes were rarely detected, suggesting that they are not common in oral bacteria. A quantitative PCR analysis showed that the relative amount of resistance determinants present in oral biofilms of the patient group was much greater than that of the healthy group, exhibiting 17-, 13-, 145-, and 3-fold increases for tet(Q), tet(M),erm(F), and cfxA, respectively. The results of this study suggest that the oral antibiotic resistome is more diverse and abundant in periodontitis patients than in healthy subjects, suggesting that there is a difference in the diversity and distribution of antibiotic resistance in oral biofilms associated with health and disease.

장떡과 소설가 황석영

김선미,Kim, Seon-Mi 한국식품연구원 2008 한맛한얼 Vol.1 No.4

System of integrating biosignals during hemodialysis: the CONTINUAL (Continuous mOnitoriNg viTal sIgN dUring hemodiALysis) registry

김선미,윤동환,권순일,Lee So-Ryoung,Kim Kwangsoo,Kim Yong Chul,김동기,Oh Kook-Hwan,주권욱,Lee Hyung-Chul,정철우,김연수,한승석 대한신장학회 2022 Kidney Research and Clinical Practice Vol.41 No.3

Background: Appropriate monitoring of intradialytic biosignals is essential to minimize adverse outcomes because intradialytic hypotension and arrhythmia are associated with cardiovascular risk in hemodialysis patients. However, a continuous monitoring system for intradialytic biosignals has not yet been developed. Methods: This study investigated a cloud system that hosted a prospective, open-source registry to monitor and collect intradialytic biosignals, which was named the CONTINUAL (Continuous mOnitoriNg viTal sIgN dUring hemodiALysis) registry. This registry was based on real-time multimodal data acquisition, such as blood pressure, heart rate, electrocardiogram, and photoplethysmogram results. Results: We analyzed session information from this system for the initial 8 months, including data for some cases with hemodynamic complications such as intradialytic hypotension and arrhythmia. Conclusion: This biosignal registry provides valuable data that can be applied to conduct epidemiological surveys on hemodynamic complications during hemodialysis and develop artificial intelligence models that predict biosignal changes which can improve patient outcomes.

예술.문화 - 라이스 푸딩과 서머싯 몸의 소설 '인간의 굴레'

김선미,Kim, Seon-Mi 한국식품연구원 2008 한맛한얼 Vol.1 No.2

G.984.3 기반의 G-PON을 위한 개선된 ONU 활성화 방안에 관한 연구

김선미,김정일,정해,Kim, Sun-Mi,Kim, Chung-Il,Chung, Hae 한국통신학회 2007 韓國通信學會論文誌 Vol.32 No.8b

PON은 BcN 액세스망의 핵심 기술인 FTTH의 구현 수단으로서 설치가 용이하고 유지보수 비용이 저렴하여 많은 관심을 받고 있다. TDMA PON의 경우, OLT는 새로운 ONU가 연결되면 거리를 측정하고 등화지연을 할당하여 모든 ONU가 논리적으로 동일한 거리에 존재하도록 하는데, 이러한 절차를 ranging이라 한다. 이 과정 동안 OLT는 수 차례의 타임 윈도우를 개설하게 되고, 이 기간에 이미 활성화된 ONU는 상향으로 데이터 전송이 금지된다. 따라서 대역폭 소모를 줄이고 원활한 서비스를 제공하기 위해서 가급적이면 타임 윈도우의 길이를 짧게 하는 것이 중요하다. 본 논문에서는 ITU-T G.984.3 기반의 G-PON의 ONU가 활성화 과정을 살펴보고, ONU의 위치정보를 모를 때 윈도우 길이를 최소화할 수 있는 효율적인 방식(algorithm I)을 제안한다. 윈도우 크기는 일련번호 등록 과정에서 얻어지는 사전 할당지연을 계산함으로써 줄일 수 있게 된다. 또한, 그것을 위치정보를 알 때 사용되는 방식(algorithm II)과 비교해 본다. 결과적으로 ONU 활성화 과정에서 첫 번째 알고리즘은 약 50%에서 90% 그리고 두 번째 알고리즘의 경우 99%까지도 윈도우 크기가 감소하게 된다. We are interested in the PON which is easy to install and inexpensive to maintain, as it is a solution of the FTTH that is a core technology of the BcN access network. When a new ONU is connected, TDMA PON has a procedure called ranging that OLT measures the distance and allocates the equalized delay to it in order to provide the same logical distance to all ONUs. For the procedure, the OLT has to open a time window several times and already activated ONUs cannot transmit a data to the upstream during the periods. Accordingly, it is important to reduce the window size for saving the bandwidth and providing a user the service smoothly. In this paper, we investigate the ONU activation method of G-PON based on ITU-T G984.3 and suggest an advanced method(algorithm I) that minimizes the window size without information of ONU distance. The size can be reduced by calculating the pre-assigned delay obtained during Serial number state. Also, we compare it with another(algorithm II) with information of distance. As a result, the window size reduces to $50{\sim}90%$ for the algorithm I and 99% for algorithm II during the ONU activation process.

유방의 노카르디아증: 증례 보고

김선미,박정미,Kim, Seon-Mi,Park, Jeong-Mi 대한영상의학회 2003 대한영상의학회지 Vol.49 No.5

노카르디아증은 주로 면역결핍환자에서 기회감염으로 발생하는 질환으로 유방에 발생하는 경우는 전세계적으로 4예정도가 보고되어 있으며,국내에서는 발표된 바 없다.저자들은 쿠싱씨 병환자에서폐감염과 동반된노카르디아에 의한 유방 농양1예를 경험하였기에그 방사선학적소견을 보고한다.병변은 유방촬영상 유방에 경계가 좋은 관상 음영이 수개 모여 있었으며 초음파 상으로는 유선과 피하지방내에 경계가 불명확하고 불규칙한 모양의 병변으로 보였고,내부에 높은 에코를보이는움직이는찌꺼기들이있었다.m Nocardiosis is an opportunistic infection occurring in immunocompromised patients. Worldwidely, about four cases of nocardiosis of the breast have been previously reported, but none of these were in Korea. We describe a case of breast nocardiosis associated with pulmonary infection in a patient with Cushing's disease. In our patient, multiple, well-defined, conglomerated, tubular-shaped, isodense mass was revealed at mammography, and an irregular-shaped, ill-defined, heterogeneous echoic mass with movable debris at ultrasonography

대학 학술정보 관리를 위한 오픈 액세스 기반 기관 레포지터리 운영방안 연구

김선미,이나니,Kim, Sun-Mi,Lee, Na-Nee 한국과학기술정보연구원 과학기술정보센터 2005 Journal of Information Science Theory and Practice Vol.36 No.2

As circumstances of scholarly communication have been changed over time, there is a growing interest among academic institutions in collecting, preserving, and creating value-added services from digital contents being created by members of the academic community. The purpose of this study is to build an open access based Institutional Repository(IR) in the university for scholarly communication. For this study, this paper analyzes the example of, and makes a full range of process and implementation plan, and then suggests a realistic model of IR which is for dissertations/theses, academic journals, working papers, etc. The intellectual property right issues related to IR are also discussed. 최근 국내외에서는 저널 구독 비용의 증가와 도서관 예산의 삭감, 그리고 대학 및 국가 지식관리의 필요성 등이 제기되면서 누구나 자유롭게 접근할 수 있는 온라인 액세스 기반의 기관 레포지터리 시스템을 도입하려는 시도가 활발하다. 이에 본 연구에서는 대학학술정보 관리를 위한 온라인 액세스 기반의 기관 레포지터리 서비스 운영방안을 살펴보고자 한다. 이를 위해서 개별기관에서의 기관 레포지터리 서비스 사례를 살펴보고, 이를 바탕으로 전체 운영 단계 및 운영방안을 마련한 후, 학위논문, 교내 간행물, 교내 학술행사, 학술지 논문/연구보고서 등에 적용할 수 있는 현실적인 운영방안을 제시하고자 하였다. 이외에 기관 레포지터리 운영시 발생할 수 있는 지적재산권 사항을 살펴보았다.