기후 변화 적응을 위한 벡터매개질병의 생태 모델 및 심층 인공 신경망 기반 공간-시간적 발병 모델링 및 예측

김상윤,남기전,허성구,이선정,최지훈,박준규,유창규,Kim, SangYoun,Nam, KiJeon,Heo, SungKu,Lee, SunJung,Choi, JiHun,Park, JunKyu,Yoo, ChangKyoo 한국화학공학회 2020 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.58 No.2

This study was carried out to analyze spatial and temporal incidence characteristics of scrub typhus and predict the future incidence of scrub typhus since the incidences of scrub typhus have been rapidly increased among vector-borne diseases. A maximum entropy (MaxEnt) ecological model was implemented to predict spatial distribution and incidence rate of scrub typhus using spatial data sets on environmental and social variables. Additionally, relationships between the incidence of scrub typhus and critical spatial data were analyzed. Elevation and temperature were analyzed as dominant spatial factors which influenced the growth environment of Leptotrombidium scutellare (L. scutellare) which is the primary vector of scrub typhus. A temporal number of diseases by scrub typhus was predicted by a deep neural network (DNN). The model considered the time-lagged effect of scrub typhus. The DNN-based prediction model showed that temperature, precipitation, and humidity in summer had significant influence factors on the activity of L. scutellare and the number of diseases at fall. Moreover, the DNN-based prediction model had superior performance compared to a conventional statistical prediction model. Finally, the spatial and temporal models were used under climate change scenario. The future characteristics of scrub typhus showed that the maximum incidence rate would increase by 8%, areas of the high potential of incidence rate would increase by 9%, and disease occurrence duration would expand by 2 months. The results would contribute to the disease management and prediction for the health of residents in terms of public health.

Nude Mouse 에 이종이식한 두경부 편평상피세포암의 분화에 대한 Retinoids의 작용

김상윤,유증주,유근식,주준범,최두영,남순열,Kim, Sang-Yoon,Yoo, Seung-Joo,Yoo, Keun-Sik,Joo, Joon-Bum,Choi, Doo-Yung,Nam, Soon-Yuhl 대한기관식도과학회 1999 大韓氣管食道科學會誌 Vol.5 No.2

Objectives : To analyze the effect of retinoids on the differentiation in HNSCC xenografts. Materials and Methods : RA (20mg/kg) or 13-cis-RA (60mg/kg) was orally administered once in a day for 30 days in the xenograft model we prepared using athymic nude mice with AMCHN-4 and -6. We carried out H & E staining and immunohistochemical staining with the monoclonal antibody against involucrin and cytokeratin 10. Results : Both RA and 13-cis-RA were found to suppress the differentiation of AMC-HN-4. Interestingly, RA enhanced the differentiation of AMC-HN-6, although 13-cis RA did not exhibit any effect on the differentiation. These results suggest that in vivo effect of retinoids on the HNSCC growth and differentiation might be various. Retinoids-induced P450 in AMC-HN-6 might be one of the mechanisms to explain the reason why the retinoids exhibit various functions in the HNSCC.

Top형 스핀밸브구조에서 반강자성체 두께 변화에 따른 자기적 특성 연구

김상윤,고훈,최경호,이창우,김지원,조순철,Kim, Sang-Yoon,Ko, Hoon,Choi, Kyoung-Ho,Lee, Chang-Woo,Kim, Ji-Won,Jo, Soon-Chul 한국자기학회 2007 한국자기학회지 Vol.17 No.1

In this research, magnetic properties of spin valve structures using IrMn layers as antiferromagnetic were studied depending on the thickness of the pinned layer. The spin valve structure was Si substrate/$SiO_2(2,000\;{\AA})/Mo(17\;{\AA})NiFe(21\;{\AA})/CoFe(28\;{\AA})/Cu(22\;{\AA})/CoFe(18\;{\AA})/IrMn(t\;{\AA})/Ta(25\;{\AA})$. Also, Mo film was deposited on Si substrates and the thermal annealing effect was analyzed. The resistivity of the Mo film was increased as an annealing temperature was increased up to $600^{\circ}C$. The variations of MR ratio were related with magnetic exchange coupling field of the spin valve structures for various IrMn pinned layer thickness up to 130 ${\AA}$. MR ratio and $H_{ex}$ of spin valves was about 9.05% and 277.5 Oe when the thickness of the IrMn pinned layer was $32.5\;{\AA}(t=32.5\;{\AA})$. It was increased to 9.65% and 337.5 Oe for $t=65\;{\AA}$. For $t=97.5\;{\AA}$, the MR ratio and Hex decreased to 8.2% and 285 Oe, and further decrease was observed up to $t=130\;{\AA}$.

Stochastic Bursting Synchronization in a Population of Subthreshold Izhikevich Neurons

김상윤,김영남,홍덕근,Jean Kim,임우창 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.60 No.9

We consider a population of subthreshold Izhikevich neurons that cannot fire spontaneously without noise. As the coupling strength passes a threshold, individual neurons exhibit noise-induced burstings (<i>i.e.</i>, discrete groups or bursts of noise-induced spikes). We investigate stochastic bursting synchronization by varying the noise intensity. Through competition between the constructive and the destructive roles of noise, collective coherence between noise-induced burstings is found to occur over a large range of intermediate noise intensities. This kind of stochastic bursting synchronization is well characterized by using the techniques of statistical mechanics and nonlinear dynamics, such as the order parameter, the raster plot of neural spikes, the time series of the ensemble-averaged global potential, and the phase portraits of limit cycles. In contrast to spiking neurons showing only spike synchronization (characterizing a temporal relationship between spikes), bursting neurons are found to exhibit both spike synchronization and burst synchronization (characterizing a temporal relationship between the onset times of the active phases of repetitive spikings). The degree of stochastic bursting synchronization is also measured in terms of a synchronization measure that reflects the resemblance of the global potential to the individual potential.

Multiple-Class Dynamic Threshold algorithm for Multimedia Traffic

김상윤,이성창,함진호,Kim, Sang-Yun,Lee, Sung-Chang,Ham, Jin-Ho The Institute of Electronics and Information Engin 2005 전자공학회논문지TC (Telecommunications) Vol.42 No.12

Traditional Internet applications such as FIP and E-mail are increasingly sharing bandwidth with newer, more demanding applications such as Web browsing, IP telephony, video conference and online games. These new applications require Quality of Service (QoS), in terms of delay, loss and throughput that are different from QoS requirements of traditional applications. Unfortunately, current Active Queue Management (AQM) approaches offer monolithic best-effort service to all Internet applications regardless of the current QoS requirements. This paper proposes and evaluates a new AQM technique, called MCDT that provides dynamic and separated buffer threshold for each Applications, those are FTP and e-mail on TCP traffic, streaming services on tagged UDP traffic, and the other services on untagged UDP traffic. Using a new QoS metric, our simulations demonstrate that MCDT yields higher QoS in terms of the delay variation and a packet loss than RED when there are heavy UDP traffics that include streaming applications and data applications. MCDT fits the current best-effort Internet environment without high complexity.

워터제트직기 구동시스템의 동특성 해석

김상윤,박대규,전두환,박명규,Kim, Sang-Yoon,Park, Dae-Kyu,Chun, Du-Hwan,Park, Myung-Kyu 한국전산구조공학회 2008 한국전산구조공학회논문집 Vol.21 No.5

While high speed / precision investigating for maximization of Textile Machinery business is requesting a machine which has highly endurance, stability and reliance abilities following customer request. In this research, load volume that gives influence on loom is measured and analyzed for water jet loom in real operation time to driving system adhered torque sensor to each a module. As well, measurement and analysis technology are developed about torque and vibration of driving systems for textile machinery by comparing dynamical analysis of water jet loom with gained result, basic materials about development of high value added textile machinery which has endurance and stability are presented.

금속분말 사출성형법을 이용한 자수기용 로터리 훅 제조 연구

김상윤,박시우,정일섭,정재옥,조규상,Kim, Sang Yoon,Park, Si Woo,Chung, Ilsup,Jung, Jae Ok,Cho, Kyu Sang 한국섬유공학회 2017 한국섬유공학회지 Vol.54 No.4

Embroidery process is the last stage of manufacturing textile products by sewing thread mechanism. The rotary hook that is manufactured by several stages of precision machining is a key part of completing the knot in embroidery. The rotary hook was manufactured by applying MIM (metal injection molding) techniques techniques, which combine the advantages of injection molding and metal powder sintering technologies, to obtain high productivity and dimensional accuracy. The sintering of injection product was performed at a temperature between $600^{\circ}C$ and $1,275^{\circ}C$ in an atmosphere of Argon with a relative density of 99% at $1,275^{\circ}C$ to 99% at the sintering temperature. A product with a hardness of 700 HV was manufactured by heat treatment. All the prescribed patterns were completed without obtaining a prescribed pattern for the developed prototype. Further, the wear test of the hook body carried out using gold thread also showed a similar decrease in size compared to that of the existing product. In this study, the manufacturing method was developed by applying MIM techniques to replace the manufacturing process of the rapidly executed rotary hook that entails various stages of machining. The developed manufacturing process is expected to boost the competitiveness of Korea's embroidery industry by replacing imports and contributing to more than 30% cost savings.

Low-Tube-Voltage CT Urography Using Low-Concentration-Iodine Contrast Media and Iterative Reconstruction: A Multi-Institutional Randomized Controlled Trial for Comparison with Conventional CT Urography

김상윤,Jeong Yeon Cho,이중엽,황성일,문민환,이은주,홍성숙,김찬교,김경아,박성빈,성득제,김용수,You Me Kim,정성일,나성은,김동원,이현,심영섭,황인평,우성민,최혁재 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.6

Objective: To compare the image quality of low-tube-voltage and low-iodine-concentration-contrast-medium (LVLC) computed tomography urography (CTU) with iterative reconstruction (IR) with that of conventional CTU. Materials and Methods: This prospective, multi-institutional, randomized controlled trial was performed at 16 hospitals using CT scanners from various vendors. Patients were randomly assigned to the following groups: 1) the LVLC-CTU (80 kVp and 240 mgI/mL) with IR group and 2) the conventional CTU (120 kVp and 350 mgI/mL) with filtered-back projection group. The overall diagnostic acceptability, sharpness, and noise were assessed. Additionally, the mean attenuation, signalto- noise ratio (SNR), contrast-to-noise ratio (CNR), and figure of merit (FOM) in the urinary tract were evaluated. Results: The study included 299 patients (LVLC-CTU group: 150 patients; conventional CTU group: 149 patients). The LVLCCTU group had a significantly lower effective radiation dose (5.73 ± 4.04 vs. 8.43 ± 4.38 mSv) compared to the conventional CTU group. LVLC-CTU showed at least standard diagnostic acceptability (score ≥ 3), but it was non-inferior when compared to conventional CTU. The mean attenuation value, mean SNR, CNR, and FOM in all pre-defined segments of the urinary tract were significantly higher in the LVLC-CTU group than in the conventional CTU group. Conclusion: The diagnostic acceptability and quantitative image quality of LVLC-CTU with IR are not inferior to those of conventional CTU. Additionally, LVLC-CTU with IR is beneficial because both radiation exposure and total iodine load are reduced.

담관낭종 -대한소아외과학회회원 대상 전국조사-

최금자,김대연,김상윤,김성철,김신곤,김우기,김인구,김재억,김재천,김해영,김홍주,박귀원,박우현,박진영,백홍규,서정민,송영택,오수명,유수영,이두선,이명덕,이석구,이성철,박영식,이태훈,정상영,Choi, Kum-Ja,Kim, D.Y.,Kim, S.Y.,Kim, S.C.,Kim, S.K.,Kim, W.K.,Kim, I.K.,Kim, J.E.,Kim, J.C.,Kim 대한소아외과학회 2003 소아외과 Vol.9 No.1

A nationwide survey on choledochal cyst was undertaken among 39 members of the Korean Association of Pediatric Surgeons. The members were required to complete a questionnaire and the case registration form for each patient during the five year period of 1997 to 2001. Three hundred and forty eight patients were registered from 32 institutions. The average number of patients per surgeon was one to two every year. The male to female ratio was 1:3.4. The age of patients on diagnosis was $49.0{\pm}44.4$ months. The geographic distribution was 34.8% in Seoul and Kyoungki-do, 33.3% in Kyoungsang-do, 17.9% in Cholla-do, and 8.5% in Choongchung-do, in order of frequency. The three common clinical presentations were abdominal pain (63.8%), vomiting (35.3%), and jaundice (29.1%). Only seven patients (2%) presented with classic triad, and 25 patients were diagnosed by antenatal ultrasonographic examination. According to the Todani Classification, 238 patients (7l.3%) were type 1, 3 (0.9%) type 11, and 93 (27.8%) type IV. At the time of the operation, three important associated conditions were choledocholithiasis in 45 patients (15.1%), liver fibrosis (Grade 1-4) in 35, and previous operative procedure for biliary diseases in 10. Associated anomalies were observed in 13 patients (3.8%). Three hundred thirty nine (98.8%) of 343 lesions were treated by Cyst excision and Roux-Y hepaticoiejunostomy. One hundred seventy-six patients had an anomalous arrangement of the pancreatobiliary ductal system (APBD): APBD was not in 92 patients, biliary duct joined to the pancreatic duct in 51, and pancreatic duct joined to the biliary duct in 26. There were 8.5% early, and 7.7% late phase operative complications. The major complications were bleeding, anastomotic leakage, and acute pancreatitis. The combination of acute abdomen and choledochal cyst may suggest spontaneous rupture. Because of the development of late intrahepatic bile duct stones, long term follow up after cyst excision and hepaticojejunostomy is required. The optimal time of surgical intervention should also be considered in the situation of routine use of antenatal ultrasonographic examination. This is the first review of the choledochal cyst in Korea and provides baseline data for future comparisons.

대한소아외과학회 회원의 1995년도 진료현황 및 수련경력 설문조사

김우기,김상윤,김신곤,김인구,김재억,김종석,김현학,박귀원,박영식,박우현,박주섭,송영택,양정우,오수명,이두선,이명덕,이석구,이성철,장수일,정성은,정풍만,최금자,최순옥,허영수,황의호,Kim, W.K.,Kim, S.Y.,Kim, S.K.,Kim, I.K.,Kim, J.E.,Kim, C.S.,Kim, H.H.,Park, K.W.,Park, Y.S.,Park, W. 대한소아외과학회 1997 소아외과 Vol.3 No.1

To understand the current status of pediatric surgical practice of the members of the Korean Association of Pediatric Surgeons, a survey of the practice of the 31 members in both 1994 and 1995. Twenty five members(80%) representing 20 hospitals responded. An average of four hundred and seventy four cases pediatric surgical operations were performed at individual institution in 1995 with 40 newborn cases. Eighteen members(72%) are currently working at university hospital. Fourteen institutions(70%) are currently classified as tertiary by the health insurance agency. The majority(15 to 60%) of members are working in the metropolitan Seoul area, while five in Taegu area. Sixteen members reported having the title of department head/director. Four members reported occasional non-pediatric surgical practice. Nine members out of 20 reported having independent pediatric surgical out-patient clinic before the establishment of the association(1985). Eight out of 15 members reported being appointed chief of pediatric surgery before 1985. In 20 institutions, 34 full time physicians(27 members, reportedly) are working in pediatric surgery. In regarding to pediatric surgical training, 16 members(64%) received an average of 16 months of training abroad, 5 members trained at home and abroad, and 4 from only at home. There are no differences in length of training periods in these groups. Twenty one members received their basic pediatric surgical training before 1985, the year of inauguration of the association. Twelve members received post-pediatric surgery refresher courses averaging 11 months' duration, after 2-11 years. Thirteen participants of this study belongs to the founding members of the association.