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Learning Delaunay Triangulation using Self-attention and Domain Knowledge [article]

Jaeseung Lee, Woojin Choi, Jibum Kim
2021 arXiv   pre-print
CRediT authorship contribution statement Jaeseung Lee: Software, Methodology, Investigation, Woojin Choi: Software, Investigation, Jibum Kim: Writing -Methodology, Supervison, Review & Editing Declaration  ... 
arXiv:2107.01759v1 fatcat:5sxfwmyr75a2fipw4tqtxw5l5u

Strong solutions to the inhomogeneous Navier-Stokes-BGK system [article]

Young-Pil Choi, Jaeseung Lee, Seok-Bae Yun
2019 arXiv   pre-print
In this paper, we are concerned with the local-in-time well-posedness of a fluid-kinetic model in which the BGK model with density dependent collision frequency is coupled with the inhomogeneous Navier-Stokes equation through drag forces. To the best knowledge of authors, this is the first result on the existence of local-in-time smooth solution for particle-fluid model with nonlinear inter-particle operator for which the existence of time can be prolonged as the size of initial data gets smaller.
arXiv:1909.10680v1 fatcat:xfoy7k6fhzfh5awhc6gnn5ajfy

Pose-MUM : Reinforcing Key Points Relationship for Semi-Supervised Human Pose Estimation [article]

JongMok Kim, Hwijun Lee, Jaeseung Lim, Jongkeun Na, Nojun Kwak, Jin Young Choi
2022 arXiv   pre-print
A well-designed strong-weak augmentation strategy and the stable teacher to generate reliable pseudo labels are essential in the teacher-student framework of semi-supervised learning (SSL). Considering these in mind, to suit the semi-supervised human pose estimation (SSHPE) task, we propose a novel approach referred to as Pose-MUM that modifies Mix/UnMix (MUM) augmentation. Like MUM in the dense prediction task, the proposed Pose-MUM makes strong-weak augmentation for pose estimation and leads
more » ... he network to learn the relationship between each human key point much better than the conventional methods by adding the mixing process in intermediate layers in a stochastic manner. In addition, we employ the exponential-moving-average-normalization (EMAN) teacher, which is stable and well-suited to the SSL framework and furthermore boosts the performance. Extensive experiments on MS-COCO dataset show the superiority of our proposed method by consistently improving the performance over the previous methods following SSHPE benchmark.
arXiv:2203.07837v1 fatcat:fzbgpyqkujgopernag573ku27u

Determination and Quantification of Heavy Metals in Sediments through Laser-Induced Breakdown Spectroscopy and Partial Least Squares Regression

Sangmi Yoon, Jaeseung Choi, Seung-Jae Moon, Jung Hyun Choi
2021 Applied Sciences  
Conventional analysis techniques and sample preprocessing methods for identifying trace metals in soil and sediment samples are costly and time-consuming. This study investigated the determination and quantification of heavy metals in sediments by using a Laser-Induced Breakdown Spectroscopy (LIBS) system and multivariate chemometric analysis. Principle Component Analysis (PCA) was conducted on the LIBS spectra at the emission lines of 11 selected elements (Al, Ca, Cd, Cr, Fe, K, Mg, Na, Ni,
more » ... and Si). The results showed apparent clustering of four types of sediment samples, suggesting the possibility of application of the LIBS technique for distinguishing different types of sediments. Mainly, the Cd, Cr, and Pb concentrations in the sediments were analyzed. A data-smoothing method—namely, the Savitzky–Golay (SG) derivative—was used to enhance the performance of the Partial Least Squares Regression (PLSR) model. The performance of the PLSR model was evaluated in terms of the coefficient of determination (R2), Root Mean Square Error of Calibration (RMSEC), and Root Mean Square Error of Cross Validation (RMSECV). The results obtained using the PLSR with the SG derivative were improved in terms of the R2 and RMSECV, except for Cr. In particular, the results for Cd obtained with the SG derivative showed a decrease of 25% in the RMSECV value. This demonstrated that the PLSR model with the SG derivative is suitable for the quantitative analysis of metal components in sediment samples and can play a significant role in controlling and managing the water quality of rivers.
doi:10.3390/app11157154 fatcat:ndm226xbefck7boyxkcqz75nli

Detection of Microplastic in Salts Using Terahertz Time-Domain Spectroscopy

Jaeseung Im, Taewon Goo, Jugyoung Kim, Soobong Choi, Sung Ju Hong, Young-Mi Bahk
2021 Sensors  
We report on a prototypical study of the detection of microplastic embedded in table salts by using terahertz time-domain spectroscopy. In the experiment, high-density polyethylene (HDPE) of sizes from 150 to 400 μm are used as a representative microplastic and mixed with table salts. Analyzing terahertz transmittance with an effective medium model, we extract various optical properties such as refractive index, absorption coefficient, and real/imaginary parts of the dielectric constant of the
more » ... ixture. Consequently, the optical properties exhibit volume-ratio-dependence in 0.1-0.5 THz regimes. Especially, the refractive index and the real part of the dielectric constant possess monotonic frequency dependence, meaning that the quantities can be relevant indicators for the detection of the microplastic in terms of practical applications. Our work proves that terahertz time-domain spectroscopy can pave a way to recognize microplastic mixed with salts and be expanded for detecting various micro-sized particles.
doi:10.3390/s21093161 pmid:34063265 pmcid:PMC8125003 fatcat:64kz7jfxgrhy3b63o2km2ri4yi

Character drawing style in cartoons on empathy induction: an eye-tracking and EEG study

Yong-il Lee, Yeojeong Choi, Jaeseung Jeong
2017 PeerJ  
. • Yeojeong Choi conceived and designed the experiments, performed the experiments, analyzed the data, wrote the paper, reviewed drafts of the paper. • Jaeseung Jeong conceived and designed the experiments  ...  Competing Interests Yeojeong Choi is a graduate of Korea Advanced Institute of Science and Technology and an employee of LG electronics. The authors declare there are no competing interests.  ... 
doi:10.7717/peerj.3988 pmid:29152415 pmcid:PMC5687150 fatcat:yb3jftpjybdkhglemsdyc5tl64

Regulation of vascular endothelial growth factor signaling by miR-200b

Young-Chul Choi, Sena Yoon, Yongsu Jeong, Jaeseung Yoon, Kwanghee Baek
2011 Molecules and Cells  
doi:10.1007/s10059-011-1042-2 pmid:21544626 pmcid:PMC3887663 fatcat:vil2emqywfcancrscazx63kzna

Postoperative Recurrence of Hepatocellular Carcinoma: The Importance of Distinguishing between Intrahepatic Metastasis and Multicentric Occurrence—Response

Sungwon Kim, Jaeseung Shin, Do Young Kim, Gi Hong Choi, Myeong-Jin Kim, Jin-Young Choi
2019 Clinical Cancer Research  
doi:10.1158/1078-0432.ccr-19-1403 pmid:31481487 fatcat:gj7m6g542vaqbhgr6i2ii2glwm

Pyridinic-N-Doped Graphene Paper from Perforated Graphene Oxide for Efficient Oxygen Reduction

Gyeong Sook Bang, Gi Woong Shim, Gwang Hyuk Shin, Dae Yool Jung, Hamin Park, Won G. Hong, Jinseong Choi, Jaeseung Lee, Sung-Yool Choi
2018 ACS Omega  
We report a simple approach to fabricate a pyridinic-N-doped graphene film (N-pGF) without high-temperature heat treatment from perforated graphene oxide (pGO). pGO is produced by a short etching treatment with hydrogen peroxide. GO perforation predominated in a short etching time (∼1 h), inducing larger holes and defects compared to pristine GO. The pGO is advantageous to the formation of a pyridinic N-doped graphene because of strong NH3 adsorption on vacancies with oxygen functional groups
more » ... ring the nitrogen-doping process, and the pyridinic-N-doped graphene exhibits good electrocatalytic activity for oxygen reduction reaction (ORR). Using rotating-disk electrode measurements, we confirm that N-pGF undergoes a four-electron-transfer process during the ORR in alkaline and acidic media by possessing sufficient diffusion pathways and readily available ORR active sites for efficient mass transport. A comparison between Pt/N-pGF and commercial Pt/C shows that Pt/N-pGF has superior performance, based on its more positive onset potential and higher limiting diffusion current at -0.5 V.
doi:10.1021/acsomega.8b00400 pmid:31458755 pmcid:PMC6641923 fatcat:l6jnj7nexvcyzcrszgmjxyqnaq

Induction of growth arrest by miR-542-3p that targets survivin

Sena Yoon, Young-Chul Choi, Suman Lee, Yongsu Jeong, Jaeseung Yoon, Kwanghee Baek
2010 FEBS Letters  
Edited by Tamas Dalmay Keywords: MicroRNA miR-542-3p Cell cycle arrest Survivin 18S ribosomal RNA a b s t r a c t Survivin is a protein which functions as a mitotic regulator as well as apoptosis inhibitor. In this study, we show that introduction of synthetic miR-542-3p mimetic reduced both mRNA and protein levels of survivin. In A549 cells, luciferase reporter assay revealed that miR-542-3p targeted predicted binding sites in the 3 0 -untranslated region (3 0 -UTR) of survivin. We also
more » ... rate that ectopic expression of miR-542-3p inhibited cell proliferation by inducing Gap 1 (G1) and Gap 2/Mitosis (G2/M) cell cycle arrest. Collectively, these results suggest that survivin is a direct target of miR-542-3p and growth inhibition by miR-542-3p may have a potential utility as an anti-cancer therapy.
doi:10.1016/j.febslet.2010.08.025 pmid:20728447 fatcat:ibq32t65xrgi3gs6v5ywlsikbq

Estimation of Closest In-Path Vehicle (CIPV) by Low-Channel LiDAR and Camera Sensor Fusion for Autonomous Vehicle [article]

Hyunjin Bae, Gu Lee, Jaeseung Yang, Gwanjun Shin, Yongseob Lim, Gyeungho Choi
2021 arXiv   pre-print
In autonomous driving, using a variety of sensors to recognize preceding vehicles in middle and long distance is helpful for improving driving performance and developing various functions. However, if only LiDAR or camera is used in the recognition stage, it is difficult to obtain necessary data due to the limitations of each sensor. In this paper, we proposed a method of converting the tracking data of vision into bird's eye view (BEV) coordinates using an equation that projects LiDAR points
more » ... to an image, and a method of fusion between LiDAR and vision tracked data. Thus, the newly proposed method was effective through the results of detecting closest in-path vehicle (CIPV) in various situations. In addition, even when experimenting with the EuroNCAP autonomous emergency braking (AEB) test protocol using the result of fusion, AEB performance is improved through improved cognitive performance than when using only LiDAR. In experimental results, the performance of the proposed method was proved through actual vehicle tests in various scenarios. Consequently, it is convincing that the newly proposed sensor fusion method significantly improves the ACC function in autonomous maneuvering. We expect that this improvement in perception performance will contribute to improving the overall stability of ACC.
arXiv:2103.13952v1 fatcat:srvagghrqzbp5ovz5kg5i2hpl4

Controlled stoichiometric synthesis of DNA–quantum dot conjugates using Ni-mediated coordination chemistry

Haejin Kwon, Sukmin Hong, Heeyeon Kim, Youngseon Choi, Jaeseung Kim, Rita Song
2010 Chemical Communications  
Quantification of 6His binding on QDs. The polymer-coated QDs (25 pmol) were mixed with various equivalents of 2G6H containing an amidated C-terminal peptide (x100, 200, 500) in 10 mM borate buffer (pH 8.0) containing EDC (25 nmol). After 4 h 15 at 25 ℃, the 2G6H-QD conjugates were washed five times with 10 mM borate buffer and characterized by agarose gel electrophoresis. Gel electrophoresis was run in a 0.5x TBE buffer on a 1.5 % agarose gel at 50 V for 1 h. The 6His on 2G6H-QD was quantified
more » ... by collecting the unreacted peptide followed by a BCA peptide assay. The absorbance of the solution was measured using a UV-Vis spectrometer and the 20 absorbance at 562 nm of each sample was plotted as a function of the amount of peptide that reacted with the QDs. The BCA assay is a biochemical assay for determining the total level of protein in a solution. The total protein concentration is exhibited by a color change of the sample solution from green to purple in proportion to protein concentration, which can then be 25 measured using colorimetric techniques.
doi:10.1039/c0cc03462b pmid:20976317 fatcat:uffmam3phjexrmklr3uvz4vsnq

A Study on Analysis for Risk Distance by Electric Leakage During Flood

Jaeseung Joo, Hyeonseok Choi, Dojoon Jung
2017 Korean Society of Hazard Mitigation  
Electric shock due to the electric leakages from the street lamps or traffic lights used to happen until the 1990. After the accident causing 19 casualties during the heavy rains on July 15-16, 2011 in Seoul, Incheon and Gyeonggi-do, the administrator established laws on installing circuit breakers to the street lamps and traffic lights. However, the standing signboard along the sidewalk remains a blind stop. Though some local government have tried to keep the streets safe from the electric
more » ... ding signboards to prevent the pedestrian from getting shocked, most store-owners hardly observes and keep on using it illegally because of the promotion effects. Thus, the objects of this research were focused on providing the danger range of electric leakage in flooded situation and safety guidelines for the pedestrians.
doi:10.9798/kosham.2017.17.2.187 fatcat:a5ogkwyrwrby7asuysq4sdd5de

A Cost-Effective CNN-LSTM-Based Solution for Predicting Faulty Remote Water Meter Reading Devices in AMI Systems

Jaeseung Lee, Woojin Choi, Jibum Kim
2021 Sensors  
Automatic meter infrastructure (AMI) systems using remote metering are being widely used to utilize water resources efficiently and minimize non-revenue water. We propose a convolutional neural network-long short-term memory network (CNN-LSTM)-based solution that can predict faulty remote water meter reading (RWMR) devices by analyzing approximately 2,850,000 AMI data collected from 2762 customers over 360 days in a small-sized city in South Korea. The AMI data used in this study is a
more » ... g, highly unbalanced real-world dataset with limited features. First, we perform extensive preprocessing steps and extract meaningful features for handling this challenging dataset with limited features. Next, we select important features that have a higher influence on the classifier using a recursive feature elimination method. Finally, we apply the CNN-LSTM model for predicting faulty RWMR devices. We also propose an efficient training method for ML models to learn the unbalanced real-world AMI dataset. A cost-effective threshold for evaluating the performance of ML models is proposed by considering the mispredictions of ML models as well as the cost. Our experimental results show that an F-measure of 0.82 and MCC of 0.83 are obtained when the CNN-LSTM model is used for prediction.
doi:10.3390/s21186229 pmid:34577436 fatcat:nbymmkktt5hrffaqtlhml6fqi4

Development and Evaluation of Automatic Discharges Measurement Technology for Small Stream Monitoring

Tae Sung Cheong, Jaeseung Joo, Hyunsuk Choi, Seojun Kim
2018 Korean Society of Hazard Mitigation  
., 2008; Choi et al., 2010)                                               (1) 여기서 와 는 상관영역의 화소크기를 나타내며,   와   는 상관영역과 탐색영역내 비교영역의 잔차값으로  ...  왜곡영상을 정사영상으로 보정하기 위 해서 Fig. 3(b)와 같이 측정구간에 표정점을 설치하고 2차원 투영 좌표변환프로그램으로 촬영영상을 정사영상으로 변환 하여 유속을 계측하였다(Kim et al., 2004; Choi et al., 2010; 3.1 계측 장비 및 방법 자동유량계측기술의 유속 및 유량계측결과의 검증을 위 하여 본 본 연구에서는  ... 
doi:10.9798/kosham.2018.18.6.347 fatcat:tpjzxjsiqjaifb4ax7zpxbsvsu
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