A Novel Performance Prediction Model for Mobile GPUs

Juwon Yun(윤주원),Jinyoung Lee(이진영),Cheong Ghil Kim(김정길),Yeong-Kyu Lim(임영규),Jae-Ho Nah(나재호),Youngsik Kim(김영식),Woo-Chan Park(박우찬) 한국컴퓨터그래픽스학회 2018 한국컴퓨터그래픽스학회 학술대회 Vol.2018 No.7

ANALYSIS OF BODY MEASUREMENT ERROR ABOUT 3D SCAN DATA FOR ELDERLY

Jinhee Park,Juwon Chung,Yu Hwa Hong,Yun Ja Nam 글로벌지식마케팅경영학회 2015 Global Fashion Management Conference Vol.2015 No.06

Measuring body size with a 3D scanner can reduce inter-measurer variability and provide better accuracy compared to using a traditional methods of measurement (Park, Nam, & Park, 2009). Many size measurement projects (or studies) that measure body size established a size measurement method prior to the development of a 3D scanner and automatic size measurement programs that produce 3D virtual body size measurements (Park, &Nam, 2012). Size data measured through an automatic size measurement program are more accurate and have a lower variability that is more appropriate for body measurements (Han, & Nam, 2004; Nam, Choi, Jung, & Yun, 2004). However, this method is limited to healthy subjects who can maintain a correct posture in a 3D scanner. It is difficult for the elderly to maintain the correct posture for body measurements in ‘Basic Human Body Measurements for Technological Design’ of ISO 7250(1997). Body measurement definitions are based on vertical and horizontal directions consequently, it is hard to measure those with a bent body type even if they stand in a correct posture. Most body measurement items are automatically measured in vertical and horizontal directions because current automatic size measurement programs utilize algorithms based on typical body measurement definitions. The size measurement method based on a vertical and horizontal directions tends to have a problem for elderly individuals with a bent body type who have difficulty maintaining a correct posture for 3D scanning as defined in ISO 7250(1997)(Ashdown, & Na, 2008).This study analyzes the problem of present auto-measurement programs that use elderly’s 3D body scan data. We conducted a comparative analysis of elderly’s body sizes using an auto-measurement program from virtual 3D body scan data and direct measurement with traditional measurement methods. We establish 34 typical body size measurements for the use of data from 464 males and 472 females (total 936) between the ages of 70 to 85. For error analysis, data separated to normal values and outliers compared with ISO 20655(2003). ISO 20685 defines the accuracy of extracted measurements by classification and measurement type (segment lengths, body height/breaths/depth, large/small circumferences, and head/hand/foot dimensions). The majority of outliers for the male and female body height type was “height”. Total number of persons with outliers for Height’s data was 603; consequently, 64.4% of subjects (elderly group of 70-85 yrs.) could not maintain a correct posture when scanning. Other data also had many errors from inaccurate measurement postures. A total of 72.3% of males and 70% of females have incorrect values in small circumferences. The segment lengths’ error data was 76.5% of males and 75% of females; in addition, the head dimension’ outliers were 87% for both male and female subjects. Especially 57.46% of males had incorrect data, while 74.67% of females had a type of large circumference. Female chest circumference had significant errors due to sagging breasts. The differences identify with a correlation between type of large circumference (chest, hip, under bust, waist, waist of omphalion) and gender. There were several correlations between the many measurement errors because values over 70% of data have outliers; however, each measurement type has properties in regards to correlation. A substantial positive correlation was found between all measurements (except hip circumference) in the type of large circumference; in addition, one-way ANOVA indicated that the measurements influenced height and were statistically significant. Outliers found in height data for the elderly’s were more likely to have errors in the type of large circumference. The type of body height indicated a strong correlation and statistical significance between the axilla height and other measurements (height, waist, crotch, lateral malleolus). Axilla height with more outliers indicated that other type of body height measurements had a higher potential for errors. The posture for body measurement was standardized as standing erect; however, this study indicated that many measurement errors were possible between using an auto-measurement program and direct measurement. The value of outlier about a particular measurement item can expect increased errors about any group (height: large circumference group/ axilla height: body height group). We have to study the relation in measurements in these types ‘large circumference’ because ‘head dimensions’ types correlate between measurements in each group. We need a more detailed analysis about outliers to find the major factors for measurement errors in regards to the elderly as well as discuss the possibility of ISO measurement-standard’s application for the elderly.

SinGAN을 이용한 병리데이터 증강 기법 연구

권주원(Juwon Kwon),윤길중(Gilly Yun),김승종(Seungjong Kim),정유채(Yuchae Jung),권순철(Soon Chul Kwon) 대한전자공학회 2020 대한전자공학회 학술대회 Vol.2020 No.8

In this paper, we described a technique for improving diagnostic performance using deep learning for Oligodendroglioma, one of brain tumors. Certain diseases, such as brain tumors, have a data imbalance problem because the number of patients in each hospital is not uniform. To solve this problem, we intended to introduce a data augmentation technique using GAN, a deep learning generation model. The experiment compared the training performance of the two groups with the dataset without fake data and the dataset with additional fake data. As a result, we showed a slight improvement in training performance and training stability.

Clathrate nanocage reactor for the decomposition of greenhouse gas

Ahn, Yun-Ho,Lim, Dongwook,Min, Juwon,Kim, Jeongtak,Lee, Byeonggwan,Lee, Jae W.,Shin, Kyuchul Elsevier 2019 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.359 No.-

<P><B>Abstract</B></P> <P>The atmospheric level of nitrous oxide (N<SUB>2</SUB>O), a representative greenhouse gas, is increasing, and the decomposition of N<SUB>2</SUB>O generally requires an energy-intensive reaction. This study introduces a nano-sized cage of ionic clathrate hydrate as a nanoreactor to decompose N<SUB>2</SUB>O. Ionic species, (Me)<SUB>4</SUB>N<SUP>+</SUP> and OH<SUP>−</SUP>, are injected to boost electron transfer in the activated water-framework of ionic clathrate hydrate. Molecular N<SUB>2</SUB>O is captured in empty cages and decomposed to non-greenhouse gases of nitrogen and oxygen by the transferred electrons from the methyl radical decay. This suggests that the clathrate hydrate can be used for both the sequestration and treatment of greenhouse gases.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The tetramethylammonium hydroxide hydrate acts as a niche for N<SUB>2</SUB>O capture. </LI> <LI> The activated host water frameworks serve as nanocage reactors for N<SUB>2</SUB>O decomposition. </LI> <LI> The methyl radical decay induces electron transfer initiating a chain reaction. </LI> <LI> The ionic clathrate hydrates can play a role in both sequestration and treatment of greenhouse gases. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effects of Large Guest Molecular Structure on Thermal Expansion Behaviors in Binary (C₄H₈O + CH₄) Clathrate Hydrates

Min, Juwon,Ahn, Yun-Ho,Baek, Seungjun,Shin, Kyuchul,Cha, Minjun,Lee, Jae W. American Chemical Society 2019 The Journal of Physical Chemistry Part C Vol.123 No.34

<P>Investigating the thermal expansion of clathrate hydrates is essential for understanding their complex physicochemical properties. Although there have been various discussions on the thermal expansion, few studies have investigated the structural effect of each guest molecule. To compare the lattice expansion behaviors with cyclic and linear large guest molecules, cyclobutanol and butyraldehyde, having the same formula of C<SUB>4</SUB>H<SUB>8</SUB>O, were used as new sII hydrate formers with a help gas of CH<SUB>4</SUB>. In Raman spectra of the bonding characteristics, the peaks of the C-H stretching mode, O-H stretching mode, and O:H stretching phonon showed unique shift behaviors as the temperature rises. A crystallographic analysis using high-resolution powder diffraction showed that the (cyclobutanol + CH<SUB>4</SUB>) hydrate undergoes smaller lattice expansion than the (butyraldehyde + CH<SUB>4</SUB>) hydrate under thermal stimulations, and the phase equilibria showed that the cyclobutanol case involves milder formation conditions than the butyraldehyde case. These structural effects could be based on the different guest-host interactions, and molecular dynamics simulation results also show that the different thermal expansivity or molecular motion of the large guest in a hydrate cage causes these unique interactions. The results of this study provide insight into distinctive guest-host interactions depending on the guest structure and their effects on the hydrate lattice.</P> [FIG OMISSION]</BR>

과학 로켓 적용을 위한 2,500 N 급 H₂O₂/HDPE 하이브리드 로켓 설계

윤용태(Yongtae Yun),허정무(Jeongmoo Huh),김영일(Youngil Kim),안병욱(Byeonguk Ahn),김주원(Juwon Kim),권세진(Sejin Kwon) 한국항공우주학회 2017 한국항공우주학회 학술발표회 논문집 Vol.2017 No.4

달 착륙선 모듈의 로켓 추력조절 및 호버링을 위한 기초 비행시험

윤용태(Yongtae Yun),허정무(Jeongmoo Huh),김주원(Juwon Kim),안병욱(Byeonguk Ahn),정우석(Woosuk Jung),권세진(Sejin Kwon) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.12

본 실험에서는 달 착륙선 모듈에 추력 조절이 가능한 250 N H₂O₂/polyethylene 하이브리드 로켓과 MCU(Micro controller unit)를 적용하여 기초적인 지상 비행시험을 수행하였다. 지상 비행시험을 위해 PD제어를 이용한 시뮬레이션, 초음파센서의 거리 측정 및 서보모터 각도변환에 따른 밸브 개폐 면적 조절하여 추력조절을 시도하였다. 비행시험 결과를 바탕으로 하여 MCU를 활용한 로켓 추력조절의 시스템 적용 가능성 및 향후 비행시험 개선방안에 대해 고찰하였다. In this experiment, a preliminary flight test was conducted for a lunar module equipped with a 250N-class H₂O₂-polyethylene hybrid rocket engine that allows adjustable thrust and micro-controller unit. First, hovering was simulated through PD control for flight test. Additionally, the throttling valve was tested experimentally on a lunar module using MCU coupled with an ultrasonic sensor and servomotor for controlling the throttle valve opening. Preliminary results demonstrate the feasibility of rocket throttling using MCU and include further improvements based on flight test.

기내 닥터콜과 환자의 안전

임소연(So Yun Lim),박소정(So Jung Park),전유경(Yookyung Jeon),조향기(Hyang Ki Cho),임주원(Juwon Lim) 한국항공우주의학협회 2017 항공우주의학회지 Vol.27 No.2

하비랩: 전업주부 여성들을 위한 지역기반 취미공유 플랫폼

정은빈(Eunbeen Jung),신주원(Juwon shin),구서연(Seoyeon Koo),민귀림(Gwilim Min),이현구(Hyungu Lee),소재한(Chaehan So),김나연(Nayeon Kim),호재윤(Jae Yun Ho) 한국디자인학회 2021 한국디자인학회 학술발표대회 논문집 Vol.2021 No.11

Enhanced methane hydrate formation with cyclopentane hydrate seeds

Baek, Seungjun,Ahn, Yun-Ho,Zhang, Junshe,Min, Juwon,Lee, Huen,Lee, Jae W. Elsevier 2017 APPLIED ENERGY Vol.202 No.-

<P>This work presents the kinetic promotion effect of sll cyclopentane (CP) hydrate seeds on sI CH4 hydrate formation in sodium dodecyl sulfate (SDS) solutions. Gas hydrates are one of the promising materials for natural gas storage due to their high volumetric capacity and safety aspect. Generally, a crystal layer of gas hydrate is preferentially created on the surface of an aqueous phase which results in both low hydrate conversion and slow reaction without mechanical agitations. This study introduces CP hydrate seeds at very small quantities to accelerate the nucleation and growth of the CH4 hydrate with SDS. To choose the appropriate amount of CP in the system for massive sI CH4 hydrate formation, several hydrate slurries with various amounts of CP were characterized by powder X-ray diffraction and Raman spectroscopy. Additionally, from the visual observations of the hydrate growth behavior, the direction of hydrate crystallization significantly affected the hydrate growth and conversion rate. With the highest degree of sub cooling, the volumetric storage efficiency reached 90% of the theoretical values in 50 min with no induction period, and this promotion effect was also confirmed in an expanded reactor system. Thus, sill CP hydrate seeds result in a dramatic improvement in the sI CH4 hydrate formation rate and high volumetric storage capacity. (C) 2017 Elsevier Ltd. All rights reserved.</P>