동역학 시스템을 위한 DNN 메타모델 기반의 시스템 보정 네트워크

장성일(Sungil Jang),최주환(Juhwan Choi),한성지(Seongji Han),김진균(Jin-Gyun Kim),최진환(Jin Hwan Choi) 대한기계학회 2023 대한기계학회 춘추학술대회 Vol.2023 No.11

Modeling and simulation of dynamic systems are widely used in mechanical system design and control. System identification, a process of correlation with experimental data or target data, is essential for the reliability of the implemented model. The process is possible when the relationship between various variables that affect the responses of the system can be understood. Since various assumptions and approximations are considered in the modeling process of a nonlinear system such as a multibody dynamics system, it is difficult to directly understand the relationship between variables. Therefore, a surrogate model is needed to understand the system. In this study, we propose a system identification framework using deep neural networks. This framework consists of two processes: System metamodel and System identification network. System metamodel that is trained by the nonlinear relationship between the changing output responses to the input variables of the system using a deep neural network is introduced. The data required for training the neural network is obtained from the numerical model of the system. The loss minimization process for initializing a new neural network, which is a system identification network to find an input that produces a target output is proceeded.

EFFECT OF THE FIBER LAMINATION ANGLE OF A CARBON-FIBER, LAMINATED COMPOSITE PLATE ROOF ON THE CAR INTERIOR NOISE

Sungil Bang,Yoojin Park,Yeonsoo Kim,Tae Jin Shin,Jiseon Back,이상권 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.1

The paper presents the change of the interior noise according to the lamination angles of the carbon fiber in the carbon-fiber reinforced plastic (CFRP) laminated composite plate. In the previous paper, the charateristics of the sound radiated from a CFRP plate was studied in the free field condition. In this paper, vibro-acoustic interaction for the CFRP plate with various lamination angles was studed considering the application of the CFRP plate to car roof. In order to study the vibro-acoustic interaction, a certain enclosure with flexible wall was required and then the closed rectangular box was prepared. The one flexible wall of the rectangular box consisted of CFRP plate. Three CFRP plates with fiber lamination angles of [−15/15/15/−15]s, [−30/30/30/−30]s, and [−75/75/75/−75]s were fabricated and used as one flexible wall of the closed box. These plates were excited by an impact force, and the interior sound pressure within the closed box was calculated both theoretically and experimentally. Then, the identified vibro-acoustic characteristics were used to apply the CFRP plate to the roof of a car, thereby shifting the resonance frequency of the interior noise.

국제합작투자 이사회 활동이 이사회 효과성에 미치는 영향

박성일(Sungil Park),박병진(Byung-Jin (Robert) Park) 대한경영학회 2017 大韓經營學會誌 Vol.30 No.10

LC-MS/MS를 이용한 소변 중 크레아티닌 분석의 측정불확도 평가

김진영(Jin Young Kim),권운용(Woonyong Kwon),서승일(SungIll Suh),인문교(Moon Kyo In) 한국분석과학회 2012 분석과학 Vol.25 No.1

Wogonin inhibits osteoclast formation induced by lipopolysaccharide

Jang, Sungil,Bak, Eun Jung,Kim, Minyoung,Kim, Jin Moon,Chung, Won-Yoon,Cha, Jeong-Heon,Yoo, Yun-Jung John Wiley Sons, Ltd. 2010 Phytotherapy research Vol.24 No.7

<P>To evaluate the inhibitory activity of wogonin against lipopolysaccharide (LPS)-induced bone resorption, we investigated the effect of wogonin on osteoclastogenesis induced by LPS. Wogonin inhibited LPS-induced osteoclastogenesis in co-cultures of mouse calvaria-derived osteoblasts and bone marrow-derived pre-osteoclasts. Wogonin also suppressed osteoclastogenesis in LPS-injected mouse calvaria. In osteoblasts, the upregulation of receptor activator of nuclear factor-&kgr;B (RANKL) expression and the downregulation of osteoprotegerin (OPG) expression by LPS were inhibited by wogonin. Wogonin and NS-398, a COX-2 inhibitor, suppressed LPS-stimulated PGE<SUB>2</SUB> production in osteoblasts. NS-398 inhibited the effect of LPS on RANKL and OPG expression in osteoblasts. These results suggest that wogonin acts as an inhibitor of LPS-induced osteoclastogenesis through downregulation of RANKL and upregulation of OPG expression via blockage of PGE<SUB>2</SUB> production. Based on these results, wogonin has potential for use as a therapeutic agent in bacteria-induced bone resorption. Copyright © 2009 John Wiley & Sons, Ltd.</P>

Dual-layered nanocomposite substrate membrane based on polysulfone/graphene oxide for mitigating internal concentration polarization in forward osmosis

Lim, Sungil,Park, Myoung Jun,Phuntsho, Sherub,Tijing, Leonard D.,Nisola, Grace M.,Shim, Wang-Geun,Chung, Wook-Jin,Shon, Ho Kyong Elsevier 2017 Polymer Vol.110 No.-

<P><B>Abstract</B></P> <P>A novel thin-film composite (TFC) forward osmosis (FO) membrane with dual-layered substrate membrane was fabricated by a double-blade casting technique using different polysulfone (PSf) concentrations for top (15 wt%) and bottom (7 wt%) substrate layers. Graphene oxide (GO) was incorporated in the substrate layer, and the dual casting approach resulted in a membrane support with a highly porous bottom structure and a dense top skin layer on which the polyamide active layer was effectively formed. The dual-layered TFC PSf/GO membrane (TFC-PSf<SUB>d</SUB>GO) exhibited high water permeability, and ion selectivity was enhanced by the presence of well dispersed hydrophilic GO in the PSf substrate. The TFC-PSf<SUB>d</SUB>GO also exhibited the lowest specific reverse salt flux (<I>J</I> <SUB> <I>s</I> </SUB> <I>/J</I> <SUB> <I>v</I> </SUB> = 0.19 g L<SUP>-1</SUP>) and a more favorable structural parameter (S = 130 μm) compared to GO-free membranes. Using deionized water as feed solution and 1 M NaCl as draw solution (DS), TFC-PSf<SUB>d</SUB>GO had <I>J</I> <SUB> <I>v</I> </SUB> = 33.8 L m<SUP>−2</SUP> h<SUP>−1</SUP> and <I>J</I> <SUB> <I>s</I> </SUB> = 6.9 g<SUP>−2</SUP> h<SUP>−1</SUP> under AL-FS mode, and <I>J</I> <SUB> <I>v</I> </SUB> = 61.5 L m<SUP>−2</SUP>h<SUP>−1</SUP> and <I>J</I> <SUB> <I>s</I> </SUB> = 14.0 g<SUP>−2</SUP> h<SUP>−1</SUP> under AL-DS mode. The potential of TFC-PSf<SUB>d</SUB>GO for commercial application was further evaluated by fabricating it with a fabric backing support (denoted as TFC-PSf<SUB>d</SUB>GO<SUB>f</SUB>). Compared to TFC-PSf<SUB>d</SUB>GO, TFC-PSf<SUB>d</SUB>GO<SUB>f</SUB> exhibited only 14% decline in its water flux. The overall results reveal that, fabrication of TFC substrate membrane via dual-blade casting approach along with GO incorporation produced high-performance TFC FO membranes which likely reduced the internal concentration polarization effects.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The dual-layered PSf/GO membrane was developed to mitigate the ICP effect. </LI> <LI> The dual-layered PSf substrates exhibited higher porosity and water permeability. </LI> <LI> Incorporation of GO further improved hydrophilicity of membrane substrate. </LI> <LI> The dual-layered PSf/GO membrane demonstrated the best membrane performances. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Bioactive resin-based composite with surface pre-reacted glass-ionomer filler and zwitterionic material to prevent the formation of multi-species biofilm

Lee, Myung-Jin,Kwon, Jae-Sung,Kim, Ji-Yeong,Ryu, Jeong-Hyun,Seo, Ji-Young,Jang, Sungil,Kim, Kwang-Mahn,Hwang, Chung-Ju,Choi, Sung-Hwan Elsevier 2019 Dental materials Vol.35 No.9

<P><B>Abstract</B></P> <P><B>Objective</B></P> <P>This study evaluated the synergetic effect between surface pre-reacted glass-ionomer (SPRG) filler and 2-methacryloyloxyethyl phosphorylcholine (MPC), for inhibiting multi-species biofilm formation, while maintaining or even improving the original beneficial features of SPRG-filled resin-based composite (RBC).</P> <P><B>Methods</B></P> <P>MPC (1.5–10wt%) was incorporated into commercial SPRG-filled RBC. Then, the inherent properties of RBC, and ion release and acid-neutralising properties associated with SPRG were investigated. Further, protein adsorptions and bacterial adhesion and viability on the SPRG-filled RBC surfaces were studied using four kinds of oral bacteria; <I>Streptococcus mutans</I>, <I>Actinomyces naeslundii</I>, <I>Veillonella parvula</I>, and <I>Porphyromonas gingivalis</I>. Finally, the thickness and biomass of the human saliva-derived biofilm model cultured on test and control samples were analysed.</P> <P><B>Results</B></P> <P>Addition of MPC content resulted in decreased flexural strength and wettability of SPRG-filled RBC. SPRG-filled RBC released significantly higher amounts of multiple ions as contents of MPC increased. Meanwhile, SPRG-filled RBC with 5-wt% MPC significantly improved acid-neutralising properties than those of other test and control samples (<I>P</I> <0.001). SPRG-filled RBC with 3wt% MPC significantly reduced the amount of adsorbed bovine serum albumin and proteins from the brain heart infusion medium as compared to the control (<I>P</I> <0.01). A similar trend was observed in the attachment of four types of bacteria and multi-species biofilm (<I>P</I> <0.01).</P> <P><B>Significance</B></P> <P>Despite limitation in terms of deteriorations of some physical properties, addition of 3% MPC to SPRG-filled RBC leads to inhibition of the attachment of multi-species bacteria on its surface, as well as inhibition of biofilm growth. Moreover, the original important bioactive features of SPRG-filled RBC such as ion release and acid neutralisations are either maintained or improved upon adding MPC.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A zwitterionic material (MPC, 1.5–10%) is added to commercial SPRG-filled RBC. </LI> <LI> Addition of MPC result in deteriorations of physical properties. </LI> <LI> Sample with 3% MPC inhibits attachment of multispecies bacteria on its surface. </LI> <LI> Sample with 3% MPC inhibits biofilm growth. </LI> <LI> The ion release and acid neutralisations were maintained or even improved with adding MPC. </LI> </UL> </P>

의료기사 관련 직업 명칭에 대한 비교 연구: 표준직업분류를 중심으로

김대진(Dae Jin Kim),김대은(Dae Eun Kim),구본경(Bon-Kyeong Koo),황삼노(Samnoh Hwang),권민석(Minseok Kwon),하성일(Sungil Ha),이민우(Minwoo Lee) 한국보건의료윤리학회 2023 한국보건의료윤리학회지 Vol.2 No.1

Background: This study aimed to compare job titles of Medical Technologists with international and domestic standard occupational classifications, in order to provide fundamental data for various fields such as job ethics, workplace etiquette, research papers, immigration, employment, translation, university websites, educational evaluation, and unified education systems. Methods: The study conducted a comparative analysis of data from various sources, including the International Standard Classification of Occupations 2008 revision, Korean Standard Classification of Occupations 2017 revision, Standard Occupational Classification 2018 revision, NOC, National Occupational Classification 2011 revision, occupational outlook book, O*NET, and other organizational websites. Results: The study show that Medical Technologists typically received their entry-level education from 2-3 year junior colleges or 4-year universities. The various types of Medical Technologists included clinical laboratory technologists, radiological technologists, physical therapists, occupational therapists, dental technologists, dental hygienists, health information technologists, and opticians. In Korea, there was no standardized English name for Medical Technologists, so caution must be exercised when using official English names. For example, "clinical laboratory technologist" should not be translated as "medical/clinical laboratory scientist" and "health information technologist" should not be translated as "health information manager". Additionally, "optician" should not be translated as "optometrist" as the job skills and level of education required for each job are different. Conclusion: This study is that job titles of Medical Technologists are important for their self-esteem and identity, and therefore it is appropriate to use terms translated based on domestic and international standard occupational classifications.

Simultaneous Determination of Methylphenidate, Amphetamine and their Metabolites in Urine using Direct Injection Liquid Chromatography-Tandem Mass Spectrometry

( Woonyong Kwon ),( Sungill Suh ),( Moon Kyo In ),( Jin Young Kim ) 한국질량분석학회 2014 Mass spectrometry letters Vol.5 No.4

Nonmedical use of prescription stimulants such as methylphenidate (MPH) and amphetamine (AP) by normal persons has been increased to improve cognitive functions. Due to high potential for their abuse, reliable analytical methods were required to detect these prescription stimulants in biological samples. A direct injection liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and implemented for simultaneous determination of MPH, AP and their metabolites ritalinic acid (RA) and 4-hydroxyamphetamine (HAP) in human urine. Urine sample was centrifuged and the upper layer (100 μL) was mixed with 800 μL of distilled water and 100 μL of internal standards (0.2 μg/mL in methanol). The mixture was then directly injected into the LC-MS/MS system. The mobile phase was composed of 0.2% formic acid in distilled water (A) and acetonitrile (B). Chromatographic separation was performed by using a Capcell Pak MG-II C18 (150 mm × 2.0 mm i.d., 5 μm, Shiseido) column and all analytes were eluted within 5 min. Linear least-squares regression with a 1/x weighting factor was used to generate a calibration curve and the assay was linear from 20 to 1500 ng/mL (HAP), 40-3000 ng/mL (AP and RA) and 2-150 ng/mL (MPH). The intra- and inter-day precisions were within 16.4%. The intra- and inter-day accuracies ranged from -15.6% to 10.8%. The limits of detection for all the analytes were less than 4.7 ng/mL. The suitability of the method was examined by analyzing urine samples from drug abusers.

국산 SW 무기체계 적용사례 창출

진성일(Seongil Jin),권경용(Kyungyong Kwon),김성호(Seongho Kim),김세환(Sewhan Kim),심임보(Imbo Sim),조성일(Sungil Cho) 한국정보과학회 2017 정보과학회지 Vol.35 No.12