16,688 results on '"Lee, Chung"'
Search Results
2. Confronting the Nuclear Challenge: North Korea’s Ambitions and Regional Strategies
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Town, Jenny, Lee, Chung Min, Revere, Evans J.R., Scobell, Andrew, Kurata, Hideya, and Lukin, Artyom
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- 2024
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3. Campaign Strategy of Interest Groups in Korea: The Case of the 14th Presidential Election
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Lee, Chung-Hee
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- 2024
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4. KMT-2021-BLG-0284, KMT-2022-BLG-2480, and KMT-2024-BLG-0412: Three microlensing events involving two lens masses and two source stars
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Han, Cheongho, Udalski, Andrzej, Bond, Ian A., Lee, Chung-Uk, Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Mróz, Przemek, Szymański, Michał K., Skowron, Jan, Poleski, Radosław, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Rybicki, Krzysztof A., Iwanek, Patryk, Ulaczyk, Krzysztof, Wrona, Marcin, Gromadzki, Mariusz, Mróz, Mateusz J., Abe, Fumio, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fujii, Hirosame, Fukui, Akihiko, Hamada, Ryusei, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Sumi, Takahiro, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, and Yamashita, Kansuke
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We carried out a project involving the systematic analysis of microlensing data from the Korea Microlensing Telescope Network survey. The aim of this project is to identify lensing events with complex anomaly features that are difficult to explain using standard binary-lens or binary-source models. Our investigation reveals that the light curves of microlensing events KMT-2021-BLG-0284, KMT-2022-BLG-2480, and KMT-2024-BLG-0412 display highly complex patterns with three or more anomaly features. These features cannot be adequately explained by a binary-lens (2L1S) model alone. However, the 2L1S model can effectively describe certain segments of the light curve. By incorporating an additional source into the modeling, we identified a comprehensive model that accounts for all the observed anomaly features. Bayesian analysis, based on constraints provided by lensing observables, indicates that the lenses of KMT-2021-BLG-0284 and KMT-2024-BLG-0412 are binary systems composed of M dwarfs. For KMT-2022-BLG-2480, the primary lens is an early K-type main-sequence star with an M dwarf companion. The lenses of KMT-2021-BLG-0284 and KMT-2024-BLG-0412 are likely located in the bulge, whereas the lens of KMT-2022-BLG-2480 is more likely situated in the disk. In all events, the binary stars of the sources have similar magnitudes due to a detection bias favoring binary source events with a relatively bright secondary source star, which increases detection efficiency., Comment: 9 pages, 9 figures
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- 2024
5. KMT-2024-BLG-1044L: A sub-Uranus microlensing planet around a host at the star-brown dwarf mass boundary
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Han, Cheongho, Ryu, Yoon-Hyun, Lee, Chung-Uk, Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Kim, Doeon, Kim, Dong-Jin, Park, Byeong-Gon, and Pogge, Richard W.
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Solar and Stellar Astrophysics - Abstract
We analysed microlensing data to uncover the nature of the anomaly that appeared near the peak of the short-timescale microlensing event KMT-2024-BLG-1044. Despite the anomaly's brief duration of less than a day, it was densely observed through high-cadence monitoring conducted by the KMTNet survey. Detailed modelling of the light curve confirmed the planetary origin of the anomaly and revealed two possible solutions, due to an inner--outer degeneracy. The two solutions provide different measured planet parameters: $(s, q)_{\rm inner} = [1.0883 \pm 0.0027, (3.125 \pm 0.248)\times 10^{-4}]$ for the inner solutions and $(s, q)_{\rm outer} = [1.0327 \pm 0.0054, (3.350 \pm 0.316)\times 10^{-4}]$ for the outer solutions. Using Bayesian analysis with constraints provided by the short event timescale ($t_{\rm E} \sim 9.1$~day) and the small angular Einstein radius ($\theta_{\rm E}\sim 0.16$~mas for the inner solution and $\sim 0.10$~mas for the outer solutio), we determined that the lens is a planetary system consisting of a host near the boundary between a star and a brown dwarf and a planet with a mass lower than that of Uranus. The discovery of the planetary system highlights the crucial role of the microlensing technique in detecting planets that orbit substellar brown dwarfs or very low-mass stars., Comment: 8 pages, 10 figures
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- 2024
6. An Intelligent Quantum Cyber-Security Framework for Healthcare Data Management
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Gupta, Kishu, Saxena, Deepika, Rani, Pooja, Kumar, Jitendra, Makkar, Aaisha, Singh, Ashutosh Kumar, and Lee, Chung-Nan
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Computer Science - Cryptography and Security - Abstract
Digital healthcare is essential to facilitate consumers to access and disseminate their medical data easily for enhanced medical care services. However, the significant concern with digitalization across healthcare systems necessitates for a prompt, productive, and secure storage facility along with a vigorous communication strategy, to stimulate sensitive digital healthcare data sharing and proactive estimation of malicious entities. In this context, this paper introduces a comprehensive quantum-based framework to overwhelm the potential security and privacy issues for secure healthcare data management. It equips quantum encryption for the secured storage and dispersal of healthcare data over the shared cloud platform by employing quantum encryption. Also, the framework furnishes a quantum feed-forward neural network unit to examine the intention behind the data request before granting access, for proactive estimation of potential data breach. In this way, the proposed framework delivers overall healthcare data management by coupling the advanced and more competent quantum approach with machine learning to safeguard the data storage, access, and prediction of malicious entities in an automated manner. Thus, the proposed IQ-HDM leads to more cooperative and effective healthcare delivery and empowers individuals with adequate custody of their health data. The experimental evaluation and comparison of the proposed IQ-HDM framework with state-of-the-art methods outline a considerable improvement up to 67.6%, in tackling cyber threats related to healthcare data security.
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- 2024
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7. Fast Algorithm for Full-wave EM Scattering Analysis of Large-scale Chaff Cloud with Arbitrary Orientation, Spatial Distribution, and Length
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Lee, Chung Hyun, Kang, Dong-Kook, Kwon, Kyoung Il, Kim, Kyung-Tae, and Na, Dong-Yeop
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Physics - Computational Physics - Abstract
We propose a new fast algorithm optimized for full-wave electromagnetic (EM) scattering analysis of a large-scale cloud of chaffs with arbitrary orientation, spatial distribution, and length. By leveraging the unique EM scattering characteristics in chaff clouds, we introduce the {\it sparsification via neglecting far-field coupling} strategy, which makes an impedance matrix block-banded and sparse and thereby significantly accelerates thin-wire approximate method-of-moments solvers. Our numerical studies demonstrate that the proposed algorithm can estimate the monostatic and bistatic radar cross section (RCS) of large-scale chaff clouds much faster and with greater memory efficiency than the conventional multilevel fast multipole method, while retaining the high accuracy. This algorithm is expected to be highly useful for RCS estimation of large-scale chaff clouds in practical scenarios, serving as a cost-effective ground-truth generator.
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- 2024
8. Searching for new physics using high precision absorption spectroscopy; continuum placement uncertainties and $\Delta\alpha/\alpha$ towards the quasar PHL957
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Webb, John K., Lee, Chung-Chi, Milaković, Dinko, Dougan, Darren, Dzuba, Vladimir A., and Flambaum, Victor V.
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Astrophysics - Cosmology and Nongalactic Astrophysics ,General Relativity and Quantum Cosmology - Abstract
Detecting or placing upper limits on spacetime variations of fundamental constants requires quantifying every potential source of uncertainty. We continue our previous study into the impact of continuum variations on measurements of the fine structure constant, here in the context of quasar absorption systems. An automated (hence objective and reproducible) continuum modelling method is reported in an accompanying paper. We apply the method to the $z_{abs}=1.7975$ absorption system towards the quasar PHL957. Multiple continuum fits are generated, and for each, we derive independent models of the system, each giving its own measurement of the fine structure constant $\alpha$. This process isolates and quantifies the error contribution associated with continuum placement uncertainty. This source of uncertainty, ignored in many previous measurements, arises in two ways: (i) slight local continuum tilt uncertainty generates small line shifts, and (ii) different continuum estimates produce slightly different kinematic structures in the absorption system model. Taking continuum placement uncertainty into account, the new PHL957 measurement we obtain is $\Delta\alpha/\alpha= -0.53^{+5.45}_{-5.51} \times 10^{-6}$. This measurement assumes terrestrial magnesium isotopic abundances. Recommendations are provided for future $\alpha$ measurements. Finally, we also note the potential importance of the effects identified here for future redshift drift experiments., Comment: 10 pages, 3 figures. Submitted to Open Journal of Astrophysics
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- 2024
9. Searching for new physics using high precision absorption spectroscopy; continuum placement uncertainties and the fine structure constant in strong gravity
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Lee, Chung-Chi, Webb, John K., Dougan, Darren, Dzuba, Vladimir A., Flambaum, Victor V., and Milaković, Dinko
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics ,General Relativity and Quantum Cosmology - Abstract
Searches for variations of fundamental constants require a comprehensive understanding of measurement errors. This paper examines a source of error that is usually overlooked: the impact of continuum placement error. We investigate the problem using a high resolution, high signal to noise spectrum of the white dwarf G191$-$B2B. Narrow photospheric absorption lines allow us to search for new physics in the presence of a gravitational field approximately $10^4$ times that on Earth. Modelling photospheric lines requires knowing the underlying spectral continuum level. We describe the development of a fully automated, objective, and reproducible continuum estimation method. Measurements of the fine structure constant are produced using several continuum models. The results show that continuum placement variations result in small systematic shifts in the centroids of narrow photospheric absorption lines which impact significantly on fine structure constant measurements. This effect should therefore be included in the error budgets of future measurements. Our results suggest that continuum placement variations should be investigated in other contexts, including fine structure constant measurements in stars other than white dwarfs. The analysis presented here is based on NiV absorption lines in the photosphere of G191$-$B2B. Curiously, the inferred measurement of the fine structure constant obtained in this paper using NiV (the least negative of our measurements is $\Delta\alpha/\alpha = -1.462 \pm 1.121 \times 10^{-5}$) is inconsistent with the most recent previous G191$-$B2B photospheric measurement using FeV ($\Delta\alpha/\alpha = 6.36 \pm 0.35_{stat} \pm 1.84_{sys} \times 10^{-5}$). Given both measurements are derived from the same spectrum, we presume (but in this work are unable to check) that this 3.2$\sigma$ difference results from unknown laboratory wavelength systematics., Comment: Main paper comprises 11 pages, 4 figures, 1 table. 41 pages in total including appendices. Submitted to Open Journal of Astrophysics. arXiv admin note: substantial text overlap with arXiv:2212.00434
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- 2024
10. Microlensing brown-dwarf companions in binaries detected during the 2022 and 2023 seasons
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Han, Cheongho, Bond, Ian A., Udalski, Andrzej, Lee, Chung-Uk, Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Abe, Fumio, Bando, Ken, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fujii, Hirosame, Fukui, Akihiko, Hamada, Ryusei, Hamada, Shunya, Hamasaki, Naoto, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Nagai, Tutumi, Nunota, Kansuke, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Sumi, Takahiro, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, Yamashita, Kansuke, Szymański, Przemek Mróz Michał K., Skowron, Jan, Poleski, Radosław, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Rybicki, Krzysztof A., Iwanek, Patryk, Ulaczyk, Krzysztof, Wrona, Marcin, Gromadzki, Mariusz, and Mróz, Mateusz J.
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Building on previous works to construct a homogeneous sample of brown dwarfs in binary systems, we investigate microlensing events detected by the Korea Microlensing Telescope Network (KMTNet) survey during the 2022 and 2023 seasons. Given the difficulty in distinguishing brown-dwarf events from those produced by binary lenses with nearly equal-mass components, we analyze all lensing events detected during the seasons that exhibit anomalies characteristic of binary-lens systems. Using the same criteria consistently applied in previous studies, we identify six additional brown dwarf candidates through the analysis of lensing events KMT-2022-BLG-0412, KMT-2022-BLG-2286, KMT-2023-BLG-0201, KMT-2023-BLG-0601, KMT-2023-BLG-1684, and KMT-2023-BLG-1743. An examination of the mass posteriors shows that the median mass of the lens companions ranges from 0.02 $M_\odot$ to 0.05 $M_\odot$, indicating that these companions fall within the brown-dwarf mass range. The mass of the primary lenses ranges from 0.11 $M_\odot$ to 0.68 $M_\odot$, indicating that they are low-mass stars with substantially lower masses compared to the Sun., Comment: 13 pages, 17 figures, 12 tables
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- 2024
11. Isotopic abundance of carbon in the DLA towards QSO B1331+170
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Milaković, Dinko, Webb, John K., Molaro, Paolo, Lee, Chung-Chi, Jethwa, Prashin, Cupani, Guido, Murphy, Michael T., Welsh, Louise, D'Odorico, Valentina, Cristiani, Stefano, Santos, Ricardo Génova, Martins, Carlos J. A. P., Nunes, Nelson J., Schmidt, Tobias M., Pepe, Francesco A., Osorio, Maria Rosa Zapatero, Alibert, Yann, Hernández, J. I. González, Di Marcantonio, Paolo, Palle, Enric, Santos, Nuno C., and Rebolo, Rafael
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Chemical evolution models predict a gradual build-up of $^{13}$C in the universe, based on empirical nuclear reaction rates and assumptions on the properties of stellar populations. However, old metal-poor stars within the Galaxy contain more $^{13}$C than is predicted, suggesting that further refinements to the models are necessary. Gas at high redshift provides important supplementary information at metallicities $-2\lesssim$ [Fe/H] $\lesssim-1$, for which there are only a few measurements in the Galaxy. We obtained new, high-quality, VLT/ESPRESSO observations of the QSO B1331+170 and used them to measure $^{12}$C/$^{13}$C in the damped Lyman-$\alpha$ system (DLA) at $z_{abs}=1.776$, with [Fe/H]=-1.27. AI-VPFIT, an Artificial Intelligence tool based on genetic algorithms and guided by a spectroscopic information criterion, was used to explore different possible kinematic structures of the carbon gas. Three hundred independent AI-VPFIT models of the absorption system were produced using pre-set $^{12}$C/$^{13}$C values, ranging from 4 to 500. Our results show that $^{12}$C/$^{13}$C$=28.5^{+51.5}_{-10.4}$, suggesting a possibility of $^{13}$C production at low metallicity., Comment: 11 pages, 6 figures. Three appendices. To appear in MNRAS
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- 2024
12. KMT-2021-BLG-2609Lb and KMT-2022-BLG-0303Lb: Microlensing planets identified through signals produced by major-image perturbations
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Han, Cheongho, Albrow, Michael D., Lee, Chung-Uk, Chung, Sun-Ju, Gould, Andrew, Hwang, Kyu-Ha, Jung, Youn Kil, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, and Pogge, Richard W.
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We investigate microlensing data collected by the Korea Microlensing Telescope Network (KMTNet) survey. Our investigation reveals that the light curves of two lensing events, KMT-2021-BLG-2609 and KMT-2022-BLG-0303, exhibit a similar anomaly, in which short-term positive deviations appear on the sides of the low-magnification lensing light curves. To unravel the nature of these anomalies, we meticulously analyze each of the lensing events. Our investigations reveal that these anomalies stem from a shared channel, wherein the source passed near the planetary caustic induced by a planet with projected separations from the host star exceeding the Einstein radius. We find that interpreting the anomaly of KMT-2021-BLG-2609 is complicated by the "inner--outer" degeneracy, whereas for KMT-2022-BLG-0303, there is no such issue despite similar lens-system configurations. In addition to this degeneracy, interpreting the anomaly in KMT-2021-BLG-2609 involves an additional degeneracy between a pair of solutions, in which the source partially envelops the caustic and the other three solutions in which the source fully envelopes the caustic. As in an earlier case of this so-called von Schlieffen--Cannae degeneracy, the former solutions have substantially higher mass ratio. Through Bayesian analyses conducted based on the measured lensing observables of the event time scale and angular Einstein radius, the host of KMT-2021-BLG-2609L is determined to be a low-mass star with a mass $\sim 0.2~M_\odot$ in terms of a median posterior value, while the planet's mass ranges from approximately 0.032 to 0.112 times that of Jupiter, depending on the solutions. For the planetary system KMT-2022-BLG-0303L, it features a planet with a mass of approximately $0.51~M_{\rm J}$ and a host star with a mass of about $0.37~M_\odot$. In both cases, the lenses are most likely situated in the bulge., Comment: 10 pages, 11 figures, 6 tables
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- 2024
13. Analysis of the full Spitzer microlensing sample I: Dark remnant candidates and Gaia predictions
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Rybicki, Krzysztof A., Shvartzvald, Yossi, Yee, Jennifer C., Novati, Sebastiano Calchi, Ofek, Eran O., Bond, Ian A., Beichman, Charles, Bryden, Geoff, Carey, Sean, Henderson, Calen, Zhu, Wei, Fausnaugh, Michael M., Wibking, Benjamin, Udalski, Andrzej, Poleski, Radek, Mróz, Przemek, Szymański, Michal K., Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Skowron, Jan, Ulaczyk, Krzysztof, Iwanek, Patryk, Wrona, Marcin, Ryu, Yoon-Hyun, Albrow, Michael D., Chung, Sun-Ju, Gould, Andrew, Han, Cheongho, Hwang, Kyu-Ha, Jung, Youn Kil, Shin, In-Gu, Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Hyoun-Woo, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Abe, Fumio, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fukui, Akihiko, Hamada, Ryusei, Hamada, Shunya, Hamasaki, Naoto, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Nagai, Tutumi, NUNOTA, Kansuke, Olmschenk, Greg, Ranc, Clement, Rattenbury, Nicholas J., Satoh, Yuki K., Sumi, Takahiro, Suzuki, Daisuke, Tristram, Paul . J., Vandorou, Aikaterini, Yama, Hibiki, Wyrzykowski, Lukasz, Howil, Kornel, and Kruszyńska, Katarzyna
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Astrophysics - Astrophysics of Galaxies ,Astrophysics - Solar and Stellar Astrophysics - Abstract
In the pursuit of understanding the population of stellar remnants within the Milky Way, we analyze the sample of $\sim 950$ microlensing events observed by the Spitzer Space Telescope between 2014 and 2019. In this study we focus on a sub-sample of nine microlensing events, selected based on their long timescales, small microlensing parallaxes and joint observations by the Gaia mission, to increase the probability that the chosen lenses are massive and the mass is measurable. Among the selected events we identify lensing black holes and neutron star candidates, with potential confirmation through forthcoming release of the Gaia time-series astrometry in 2026. Utilizing Bayesian analysis and Galactic models, along with the Gaia Data Release 3 proper motion data, four good candidates for dark remnants were identified: OGLE-2016-BLG-0293, OGLE-2018-BLG-0483, OGLE-2018-BLG-0662, and OGLE-2015-BLG-0149, with lens masses of $2.98^{+1.75}_{-1.28}~M_{\odot}$, $4.65^{+3.12}_{-2.08}~M_{\odot}$, $3.15^{+0.66}_{-0.64}~M_{\odot}$ and $1.4^{+0.75}_{-0.55}~M_{\odot}$, respectively. Notably, the first two candidates are expected to exhibit astrometric microlensing signals detectable by Gaia, offering the prospect of validating the lens masses. The methodologies developed in this work will be applied to the full Spitzer microlensing sample, populating and analyzing the time-scale ($t_{\rm E}$) vs. parallax ($\pi_{\rm E}$) diagram to derive constraints on the population of lenses in general and massive remnants in particular., Comment: submitted to ApJ
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- 2024
14. Determination of the Hamiltonian from the Equations of Motion with Illustration from Examples
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Lee, Chung-Ru
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Mathematical Physics ,Nonlinear Sciences - Exactly Solvable and Integrable Systems - Abstract
In this paper, we study the determination of Hamiltonian from a given equations of motion. It can be cast into a problem of matrix factorization after reinterpretation of the system as first-order evolutionary equations in the phase space coordinates. We state the criterion on the evolution matrix for a Hamiltonian to exist. In addition, the proof is constructive and an explicit Hamiltonian with accompanied symplectic structure can be obtained. As an application, we will study a few classes of dynamical systems for illustration.
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- 2024
15. Fast Last-Iterate Convergence of Learning in Games Requires Forgetful Algorithms
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Cai, Yang, Farina, Gabriele, Grand-Clément, Julien, Kroer, Christian, Lee, Chung-Wei, Luo, Haipeng, and Zheng, Weiqiang
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Computer Science - Computer Science and Game Theory ,Computer Science - Machine Learning ,Mathematics - Optimization and Control - Abstract
Self-play via online learning is one of the premier ways to solve large-scale two-player zero-sum games, both in theory and practice. Particularly popular algorithms include optimistic multiplicative weights update (OMWU) and optimistic gradient-descent-ascent (OGDA). While both algorithms enjoy $O(1/T)$ ergodic convergence to Nash equilibrium in two-player zero-sum games, OMWU offers several advantages including logarithmic dependence on the size of the payoff matrix and $\widetilde{O}(1/T)$ convergence to coarse correlated equilibria even in general-sum games. However, in terms of last-iterate convergence in two-player zero-sum games, an increasingly popular topic in this area, OGDA guarantees that the duality gap shrinks at a rate of $O(1/\sqrt{T})$, while the best existing last-iterate convergence for OMWU depends on some game-dependent constant that could be arbitrarily large. This begs the question: is this potentially slow last-iterate convergence an inherent disadvantage of OMWU, or is the current analysis too loose? Somewhat surprisingly, we show that the former is true. More generally, we prove that a broad class of algorithms that do not forget the past quickly all suffer the same issue: for any arbitrarily small $\delta>0$, there exists a $2\times 2$ matrix game such that the algorithm admits a constant duality gap even after $1/\delta$ rounds. This class of algorithms includes OMWU and other standard optimistic follow-the-regularized-leader algorithms., Comment: 27 pages, 4 figures
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- 2024
16. Four microlensing giant planets detected through signals produced by minor-image perturbations
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Han, Cheongho, Bond, Ian A., Lee, Chung-Uk, Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Abe, Fumio, Bando, Ken, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fujii, Hirosame, Fukui, Akihiko, Hamada, Ryusei, Hamasaki, Shunya Hamada Naoto, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Nagai, Tutumi, Nunota, Kansuke, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Sumi, Takahiro, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, Yamashita, Kansuke, Bachelet, Etienne, Rota, Paolo, Bozza, Valerio, Zielinski, Paweł, Street, Rachel A., Tsapras, Yiannis, Hundertmark, Markus, Wambsganss, Joachim, Wyrzykowski, Łukasz, Jaimes, Roberto Figuera, Cassan, Arnaud, Dominik, Martin, Rybicki, Krzysztof A., and Rabus, Markus
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
We investigated the nature of the anomalies appearing in four microlensing events KMT-2020-BLG-0757, KMT-2022-BLG-0732, KMT-2022-BLG-1787, and KMT-2022-BLG-1852. The light curves of these events commonly exhibit initial bumps followed by subsequent troughs that extend across a substantial portion of the light curves. We performed thorough modeling of the anomalies to elucidate their characteristics. Despite their prolonged durations, which differ from the usual brief anomalies observed in typical planetary events, our analysis revealed that each anomaly in these events originated from a planetary companion located within the Einstein ring of the primary star. It was found that the initial bump arouse when the source star crossed one of the planetary caustics, while the subsequent trough feature occurred as the source traversed the region of minor image perturbations lying between the pair of planetary caustics. The estimated masses of the host and planet, their mass ratios, and the distance to the discovered planetary systems are $(M_{\rm host}/M_\odot, M_{\rm planet}/M_{\rm J}, q/10^{-3}, \dl/{\rm kpc}) = (0.58^{+0.33}_{-0.30}, 10.71^{+6.17}_{-5.61}, 17.61\pm 2.25,6.67^{+0.93}_{-1.30})$ for KMT-2020-BLG-0757, $(0.53^{+0.31}_{-0.31}, 1.12^{+0.65}_{-0.65}, 2.01 \pm 0.07, 6.66^{+1.19}_{-1.84})$ for KMT-2022-BLG-0732, $(0.42^{+0.32}_{-0.23}, 6.64^{+4.98}_{-3.64}, 15.07\pm 0.86, 7.55^{+0.89}_{-1.30})$ for KMT-2022-BLG-1787, and $(0.32^{+0.34}_{-0.19}, 4.98^{+5.42}_{-2.94}, 8.74\pm 0.49, 6.27^{+0.90}_{-1.15})$ for KMT-2022-BLG-1852. These parameters indicate that all the planets are giants with masses exceeding the mass of Jupiter in our solar system and the hosts are low-mass stars with masses substantially less massive than the Sun., Comment: 10 pages, 12 figures, 7 tables
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- 2024
17. KMT-2023-BLG-2669: Ninth Free-floating Planet Candidate with $\theta_{\rm E}$ measurements
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Jung, Youn Kil, Hwang, Kyu-Ha, Yang, Hongjing, Gould, Andrew, Yee, Jennifer C., Han, Cheongho, Albrow, Michael D., Chung, Sun-Ju, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, and Pogge, Richard W.
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
We report a free-floating planet (FFP) candidate identified from the analysis of the microlensing event KMT-2023-BLG-2669. The lensing light curve is characterized by a short duration $(\lesssim 3\,{\rm days})$ and a small amplitude $(\lesssim 0.7\,{\rm mag})$. From the analysis, we find the Einstein timescale of $t_{\rm E} \backsimeq 0.33\,{\rm days}$ and the Einstein radius of $\theta_{\rm E} \backsimeq 4.41\,{\mu}{\rm as}$. These measurements enable us to infer the lens mass as $M = 8\,M_{\oplus} (\pi_{\rm rel} / 0.1\,{\rm mas})^{-1}$, where $\pi_{\rm rel}$ is the relative lens-source parallax. The inference implies that the lens is a sub-Neptune- to Saturn-mass object depending on its unknown distance. This is the ninth isolated planetary-mass microlens with $\theta_{\rm E} < 10\,{\mu}{\rm as}$, which (as shown by \citealt{gould22}) is a useful threshold for a FFP candidate. We conduct extensive searches for possible signals of a host star in the light curve, but find no strong evidence for the host. We investigate the possibility of using late-time high-resolution imaging to probe for possible hosts. In particular, we discuss that for the case of finite-source point-lens FFP candidates, it would be possible to search for very wide separation hosts immediately, although such searches are "high-risk, high-reward"., Comment: 26 pages, 6 figures, accepted in publication in AJ
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- 2024
18. KMT-2023-BLG-1866Lb: Microlensing super-Earth around an M dwarf host
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Han, Cheongho, Bond, Ian A., Udalski, Andrzej, Lee, Chung-Uk, Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Abe, Fumio, Bando, Ken, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fujii, Hirosame, Fukui, Akihiko, Hamada, Ryusei, Hamada, Shunya, Hamasaki, Naoto, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Nagai, Tutumi, Nunota, Kansuke, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Sumi, Takahiro, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, Yamashita, Kansuke, Mróz, Przemek, Szymański, Michał K., Skowron, Jan, Poleski, Radosław, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Rybicki, Krzysztof A., Iwanek, Patryk, Ulaczyk, Krzysztof, Wrona, Marcin, Gromadzki, Mariusz, and Mróz, Mateusz J.
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
We investigate the nature of the short-term anomaly that appears in the lensing light curve of KMT-2023-BLG-1866. The anomaly was only partly covered due to its short duration, less than a day, coupled with cloudy weather conditions and restricted nighttime duration. Considering intricacy of interpreting partially covered signals, we thoroughly explore all potential degenerate solutions. Through this process, we identify three planetary scenarios that equally well account for the observed anomaly. These scenarios are characterized by the specific planetary parameters: $(s, q)_{\rm inner} = [0.9740 \pm 0.0083, (2.46 \pm 1.07) \times 10^{-5}]$, $(s, q)_{\rm intermediate} = [0.9779 \pm 0.0017, (1.56 \pm 0.25)\times 10^{-5}]$, and $(s, q)_{\rm outer} = [0.9894 \pm 0.0107, (2.31 \pm 1.29)\times 10^{-5}]$, where $s$ and $q$ denote the projected separation (scaled to the Einstein radius) and mass ratio between the planet and its host, respectively. We identify that the ambiguity between the inner and outer solutions stems from the inner-outer degeneracy, while the similarity between the intermediate solution and the others is due to an accidental degeneracy caused by incomplete anomaly coverage. Through Bayesian analysis utilizing the constraints derived from measured lensing observables and blending flux, our estimation indicates that the lens system comprises a very low-mass planet orbiting an early M-type star situated approximately (6.2 -- 6.5)~kpc from Earth in terms of median posterior values for the different solutions. The median mass of the planet host is in the range of (0.48 -- 0.51)~$M_\odot$, and that of the planet's mass spans a range of (2.6 -- 4.0)~$M_{\rm E}$, varying across different solutions. The detection of KMT-2023-BLG-1866Lb signifies the extension of the lensing surveys to very low-mass planets that have been difficult to be detected from earlier surveys., Comment: 9 pages, 8 figures, 4 tables
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- 2024
19. OGLE-2018-BLG-0971, MOA-2023-BLG-065, and OGLE-2023-BLG-0136: Microlensing events with prominent orbital effects
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Han, Cheongho, Udalski, Andrzej, Bond, Ian A., Lee, Chung-Uk, Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Kim, Hyoun-Woo, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Mróz, Przemek, Szymański, Michał K., Skowron, Jan, Poleski, Radosław, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Rybicki, Krzysztof A., Iwanek, Patryk, Ulaczyk, Krzysztof, Wrona, Marcin, Gromadzki, Mariusz, Mróz, Mateusz J., Abe, Fumio, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fujii, Hirosame, Fukui, Akihiko, Hamada, Ryusei, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Sumi, Takahiro, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, and Yamashita, Kansuke
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Astrophysics - Solar and Stellar Astrophysics ,Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We undertake a project to reexamine microlensing data gathered from high-cadence surveys. The aim of the project is to reinvestigate lensing events with light curves exhibiting intricate anomaly features associated with caustics, yet lacking prior proposed models to explain these features. Through detailed reanalyses considering higher-order effects, we identify that accounting for orbital motions of lenses is vital in accurately explaining the anomaly features observed in the light curves of the lensing events OGLE-2018-BLG-0971, MOA-2023-BLG-065, and OGLE-2023-BLG-0136. We estimate the masses and distances to the lenses by conducting Bayesian analyses using the lensing parameters of the newly found lensing solutions. From these analyses, we identify that the lenses of the events OGLE-2018-BLG-0971 and MOA-2023-BLG-065 are binaries composed of M dwarfs, while the lens of OGLE-2023-BLG-0136 is likely to be a binary composed of an early K-dwarf primary and a late M-dwarf companion. For all lensing events, the probability of the lens residing in the bulge is considerably higher than that of it being located in the disk., Comment: 11 pages, 13 figures, 6 tables
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- 2024
20. Groundwater productivity analysis with geology in the Geumgang River region, Korea
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Moon, Sang-Ho, Park, Changhui, Kim, Hyoung Chan, Kim, Yongcheol, Kee, Weon-Seo, Lee, Chung-Mo, and Kim, Sunghyun
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- 2024
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21. CFD investigations of a shape-memory polymer foam-based endovascular embolization device for the treatment of intracranial aneurysms
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Cabaniss, Tanner L., Bodlak, Ryan, Liu, Yingtao, Colby, Geoffrey P., Lee, Hyowon, Bohnstedt, Bradley N., Garziera, Rinaldo, Holzapfel, Gerhard A., and Lee, Chung-Hao
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- 2024
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22. H-NS is a Transcriptional Repressor of the CRISPR-Cas System in Acinetobacter baumannii ATCC 19606
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Kim, Kyeongmin, Islam, Md. Maidul, Bang, Seunghyeok, Kim, Jeongah, Lee, Chung-Young, Lee, Je Chul, and Shin, Minsang
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- 2024
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23. Machine-Learning-Based Joint Defect Prediction Using Temperature Distribution of High-Frequency Induction-Brazed Copper Joints
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Lee, Chung-Woo, Woo, Suseong, and Kim, Jisun
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- 2024
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24. Heterogeneous Peridynamic Neural Operators: Discover Biotissue Constitutive Law and Microstructure From Digital Image Correlation Measurements
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Jafarzadeh, Siavash, Silling, Stewart, Zhang, Lu, Ross, Colton, Lee, Chung-Hao, Rahman, S. M. Rakibur, Wang, Shuodao, and Yu, Yue
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Condensed Matter - Materials Science ,Computer Science - Machine Learning - Abstract
Human tissues are highly organized structures with collagen fiber arrangements varying from point to point. Anisotropy of the tissue arises from the natural orientation of the fibers, resulting in location-dependent anisotropy. Heterogeneity also plays an important role in tissue function. It is therefore critical to discover and understand the distribution of fiber orientations from experimental mechanical measurements such as digital image correlation (DIC) data. To this end, we introduce the Heterogeneous Peridynamic Neural Operator (HeteroPNO) approach for data-driven constitutive modeling of heterogeneous anisotropic materials. Our goal is to learn a nonlocal constitutive law together with the material microstructure, in the form of a heterogeneous fiber orientation field, from load-displacement field measurements. We propose a two-phase learning approach. Firstly, we learn a homogeneous constitutive law in the form of a neural network-based kernel function and a nonlocal bond force, to capture complex homogeneous material responses from data. Then, in the second phase we reinitialize the learnt bond force and the kernel function, and training them together with a fiber orientation field for each material point. Owing to the state-based peridynamic skeleton, our HeteroPNO-learned material models are objective and have the balance of linear and angular momentum guaranteed. Moreover, the effects from heterogeneity and nonlinear constitutive relationship are captured by the kernel function and the bond force respectively, enabling physical interpretability. As a result, our HeteroPNO architecture can learn a constitutive model for a biological tissue with anisotropic heterogeneous response undergoing large deformation regime. Moreover, the framework is capable to provide displacement and stress field predictions for new and unseen loading instances.
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- 2024
25. Multimodal Anomaly Detection based on Deep Auto-Encoder for Object Slip Perception of Mobile Manipulation Robots
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Yoo, Youngjae, Lee, Chung-Yeon, and Zhang, Byoung-Tak
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Computer Science - Robotics ,Computer Science - Machine Learning - Abstract
Object slip perception is essential for mobile manipulation robots to perform manipulation tasks reliably in the dynamic real-world. Traditional approaches to robot arms' slip perception use tactile or vision sensors. However, mobile robots still have to deal with noise in their sensor signals caused by the robot's movement in a changing environment. To solve this problem, we present an anomaly detection method that utilizes multisensory data based on a deep autoencoder model. The proposed framework integrates heterogeneous data streams collected from various robot sensors, including RGB and depth cameras, a microphone, and a force-torque sensor. The integrated data is used to train a deep autoencoder to construct latent representations of the multisensory data that indicate the normal status. Anomalies can then be identified by error scores measured by the difference between the trained encoder's latent values and the latent values of reconstructed input data. In order to evaluate the proposed framework, we conducted an experiment that mimics an object slip by a mobile service robot operating in a real-world environment with diverse household objects and different moving patterns. The experimental results verified that the proposed framework reliably detects anomalies in object slip situations despite various object types and robot behaviors, and visual and auditory noise in the environment.
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- 2024
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26. OGLE-2023-BLG-0836L: The sixth microlensing planet in a binary stellar system
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Han, Cheongho, Udalski, Andrzej, Jung, Youn Kil, Gould, Andrew, Kim, Doeon, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Lee, Chung-Uk, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Shin, In-Gu, Yee, Jennifer C., Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Mróz, Przemek, Mróz, Mateusz J., Szymański, Michał K., Skowron, Jan, Poleski, Radosław, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Rybicki, Krzysztof A., Iwanek, Patryk, Ulaczyk, Krzysztof, Wrona, Marcin, and Gromadzki, Mariusz
- Subjects
Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Solar and Stellar Astrophysics - Abstract
Light curves of microlensing events occasionally deviate from the smooth and symmetric form of a single-lens single-source event. While most of these anomalous events can be accounted for by employing a binary-lens single-source (2L1S) or a single-lens binary-source (1L2S) framework, it is established that a small fraction of events remain unexplained by either of these interpretations. We carry out a project in which data collected by high-cadence microlensing surveys were reinvestigated with the aim of uncovering the nature of anomalous lensing events with no proposed 2L1S or 1L2S models. From the project, we find that the anomaly appearing in the lensing event OGLE-2023-BLG-0836 cannot be explained by the usual interpretations and conduct a comprehensive analysis of the event. From thorough modeling of the light curve under sophisticated lens-system configurations, we have arrived at the conclusion that a triple-mass lens system is imperative to account for the anomaly features observed in the lensing light curve. From the Bayesian analysis using the measured observables of the event time scale and angular Einstein radius, we determine that the least massive component of the lens has a planetary mass of $4.36^{+2.35}_{-2.18}~M_{\rm J}$. This planet orbits within a stellar binary system composed of two stars with masses $0.71^{+0.38}_{-0.36}~M_\odot$ and $0.56^{+0.30}_{-0.28}~M_\odot$. This lensing event signifies the sixth occurrence of a planetary microlensing system in which a planet belongs to a stellar binary system., Comment: 11 pages, 12 figures
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- 2024
27. MOA-2022-BLG-563Lb, KMT-2023-BLG-0469Lb, and KMT-2023-BLG-0735Lb: Three sub-Jovian-mass microlensing planets
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Han, Cheongho, Jung, Youn Kil, Bond, Ian A., Gould, Andrew, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Lee, Chung-Uk, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Yang, Hongjing, Yee, Jennifer C., Zang, Weicheng, Cha, Sang-Mok, Kim, Doeon, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Abe, Fumio, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Fujii, Hirosame, Fukui, Akihiko, Hamada, Ryusei, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Sumi, Takahiro, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, and Yamashita, Kansuke
- Subjects
Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
We analyze the anomalies appearing in the light curves of the three microlensing events MOA-2022-BLG-563, KMT-2023-BLG-0469, and KMT-2023-BLG-0735. The anomalies exhibit common short-term dip features that appear near the peak. From the detailed analyses of the light curves, we find that the anomalies were produced by planets accompanied by the lenses of the events. For all three events, the estimated mass ratios between the planet and host are on the order of $10^{-4}$: $q\sim 8 \times 10^{-4}$ for MOA-2022-BLG-563L, $q\sim 2.5\times 10^{-4}$ for KMT-2023-BLG-0469L, and $q\sim 1.9\times 10^{-4}$ for KMT-2023-BLG-0735L. The interpretations of the anomalies are subject to a common inner-outer degeneracy, which causes ambiguity when estimating the projected planet-host separation. We estimated the planet mass, $M_{\rm p}$, host mass, $M_{\rm h}$, and distance, $D_{\rm L}$, to the planetary system by conducting Bayesian analyses using the observables of the events. The estimated physical parameters of the planetary systems are $(M_{\rm h}/M_\odot, M_{\rm p}/M_{\rm J}, D_{\rm L}/{\rm kpc}) = (0.48^{+0.36}_{-0.30}, 0.40^{+0.31}_{-0.25}, 6.53^{+1.12}_{-1.57})$ for MOA-2022-BLG-563L, $(0.47^{+0.35}_{-0.26}, 0.124^{+0.092}_{-0.067}, 7.07^{+1.03}_{-1.19})$ for KMT-2023-BLG-0469L, and $(0.62^{+0.34}_{-0.35}, 0.125^{+0.068}_{-0.070}, 6.26^{+1.27}_{-1.67})$ for KMT-2023-BLG-0735L. According to the estimated parameters, all planets are cold planets with projected separations that are greater than the snow lines of the planetary systems, they have masses that lie between the masses of Uranus and Jupiter of the Solar System, and the hosts of the planets are main-sequence stars that are less massive than the Sun., Comment: 11 pages, 7 tables, 10 figures
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- 2024
28. Systematic KMTNet Planetary Anomaly Search. XI. Complete Sample of 2016 Sub-Prime Field Planets
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Shin, In-Gu, Yee, Jennifer C., Zang, Weicheng, Han, Cheongho, Yang, Hongjing, Gould, Andrew, Lee, Chung-Uk, Udalski, Andrzej, Sumi, Takahiro, Albrow, Michael D., Chung, Sun-Ju, Hwang, Kyu-Ha, Jung, Youn Kil, Ryu, Yoon-Hyun, Shvartzvald, Yossi, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Hyoun-Woo, Kim, Seung-Lee, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Mróz, Przemek, Szymański, Michał K., Skowron, Jan, Poleski, Radosław, Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Rybicki, Krzysztof A., Iwanek, Patryk, Ulaczyk, Krzysztof, Wrona, Marcin, Gromadzki, Mariusz, Abe, Fumio, Bando, Ken, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Bond, Ian A., Fujii, Hirosane, Fukui, Akihiko, Hamada, Ryusei, Hamada, Shunya, Hamasaki, Naoto, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Koshimoto, Naoki, Matsubara, Yutaka, Miyazaki, Shota, Muraki, Yasushi, Nagai, Tutumi, Nunota, Kansuke, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Suzuki, Daisuke, Tomoyoshi, Mio, Tristram, Paul . J., Vandorou, Aikaterini, Yama, Hibiki, and Yamashita, Kansuke
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
Following Shin et al. (2023b), which is a part of the Systematic KMTNet Planetary Anomaly Search series (i.e., a search for planets in the 2016 KMTNet prime fields), we conduct a systematic search of the 2016 KMTNet sub-prime fields using a semi-machine-based algorithm to identify hidden anomalous events missed by the conventional by-eye search. We find four new planets and seven planet candidates that were buried in the KMTNet archive. The new planets are OGLE-2016-BLG-1598Lb, OGLE-2016-BLG-1800Lb, MOA-2016-BLG-526Lb, and KMT-2016-BLG-2321Lb, which show typical properties of microlensing planets, i.e., giant planets orbit M dwarf host stars beyond their snow lines. For the planet candidates, we find planet/binary or 2L1S/1L2S degeneracies, which are an obstacle to firmly claiming planet detections. By combining the results of Shin et al. (2023b) and this work, we find a total of nine hidden planets, which is about half the number of planets discovered by eye in 2016. With this work, we have met the goal of the systematic search series for 2016, which is to build a complete microlensing planet sample. We also show that our systematic searches significantly contribute to completing the planet sample, especially for planet/host mass ratios smaller than $10^{-3}$, which were incomplete in previous by-eye searches of the KMTNet archive., Comment: 63 pages, 16 Tables, 19 Figures, Submitted in the AAS journal
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- 2024
29. Feedback on Physical Activity Through a Wearable Device Connected to a Mobile Phone App in Patients With Metabolic Syndrome: Pilot Study
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Huh, Up, Tak, Young Jin, Song, Seunghwan, Chung, Sung Woon, Sung, Sang Min, Lee, Chung Won, Bae, Miju, and Ahn, Hyo Young
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Information technology ,T58.5-58.64 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundLittle is known of the effect of wearable devices on metabolic impairments in clinical settings. We hypothesized that a wearable device that can monitor and provide feedback on physical activity may help resolve metabolic syndrome. ObjectiveThis study aimed to examine the objective effects of the use of these devices on metabolic syndrome resolution. MethodsPatients diagnosed with metabolic syndrome were recruited. Participants were prescribed regular walking using a wearable device (Coffee WALKIE +Dv.3, GC Healthcare CI, Korea) on their wrist for 12 weeks. Participants received self-feedback on the amount of their exercise through an app on their mobile phone. The information on physical activities of the participants was uploaded automatically to a website. Thus, a trained nurse could provide individuals with feedback regarding the physical activity via telephone consultation on alternate weeks. Blood pressure (BP), body composition, fasting plasma glucose, and lipid profiles were recorded. The primary outcome was metabolic syndrome resolution. The secondary outcome was an improvement in the components of metabolic impairment. ResultsOf the 53 participants recruited, 20 participants with a median age of 46 (range 36-50) years completed the trial. There was no significant difference in the amount of calorie expenditure at weeks 4, 8, and 12. After 12 weeks, metabolic syndrome was resolved in 9 of 20 participants (45%), and the mean number of metabolic impairment components per person decreased from 3.4 to 2.9. Particularly, the mean systolic and diastolic BP decreased from mean 136.6 (SD 18.5) mm Hg to mean 127.4 (SD 19.5) mm Hg and from mean 84.0 (SD 8.1) mm Hg to mean 77.4 (SD 14.4) mm Hg (both P=.02), respectively. ConclusionsThis study found that a 12-week intervention via feedback, based on a wearable physical activity monitor, helped metabolic syndrome patients to be more engaged in regular walking and it improved impaired metabolic components, especially in BP. However, some practical challenges regarding patients’ adherence and sustained engagement were observed.
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- 2019
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30. The Clinical Outcome of Carotid Blowout Syndrome Showing Non-bleeding Angiography
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Lee, Bo-Ching, Hu, Yung-Ching, Lin, Yen-Heng, Chen, Ya-Fang, Hsieh, Hong-Jen, and Lee, Chung-Wei
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- 2024
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31. Efficient straggler task management in cloud environment using stochastic gradient descent with momentum learning-driven neural networks
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Swain, Smruti Rekha, Parashar, Anshu, Singh, Ashutosh Kumar, and Lee, Chung Nan
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- 2024
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32. Convergence properties of fine structure constant measurements using quasar absorption systems
- Author
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Webb, John K. and Lee, Chung-Chi
- Subjects
Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
Searches for spacetime variations of fundamental constants have entered an era of unprecedented precision. New, high quality quasar spectra require increasingly refined analytic methods. In this article, a continuation in a series to establish robust and unbiased methodologies, we explore how convergence criteria in non-linear least squares optimisation impact on quasar absorption system measurements of the fine structure constant alpha. Given previous claims for high-precision constraints, we critically examine the veracity of a so-called ``blinding'' approach, in which alpha is fixed at the terrestrial value during the model building process, releasing it as a free parameter only after the ``final'' absorption system kinematic structure has been obtained. We show that this approach results in an extended flat canyon in chi squared-alpha space, such that convergence is unlikely to be reached, even after as many as 1000 iterations. The fix is straightforward: alpha must be treated as a free parameter from the earliest possible stages of absorption system model building. The implication of the results presented here is that all previous measurements that have used initially-fixed alpha should be reworked., Comment: 10 pages, 13 figures. Submitted for publication
- Published
- 2023
33. The Mystery of Alpha and the Isotopes
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Webb, John K., Lee, Chung-Chi, Milakovic, Dinko, Flambum, Victor V., Dzuba, Vladimir A., and Magueijo, Joao
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Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - Astrophysics of Galaxies ,General Relativity and Quantum Cosmology - Abstract
We report unbiased AI measurements of the fine structure constant alpha in two proximate absorption regions in the spectrum of the quasar HE0515-4414. The data are high resolution, high signal to noise, and laser frequency comb calibrated, obtained using the ESPRESSO spectrograph on the VLT. The high quality of the data and proximity of the regions motivate a differential comparison, exploring the possibility of spatial variations of fundamental constants, as predicted in some theories. We show that if the magnesium isotopic relative abundances are terrestrial, the fine structure constants in these two systems differ at the 7-sigma level. A 3-sigma discrepancy between the two measurements persists even for the extreme non-terrestrial case of 100% ^{24}Mg, if shared by both systems. However, if Mg isotopic abundances take independent values in these two proximate systems, one terrestrial, the other with no heavy isotopes, both can be reconciled with a terrestrial alpha, and the discrepancy between the two measurements falls to 2-sigma. We discuss varying constant and varying isotope interpretations and resolutions to this conundrum for future high precision measurements., Comment: 6 pages, 3 figures
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- 2023
34. OGLE-2017-BLG-0448Lb: A Low Mass-Ratio Wide-Orbit Microlensing Planet?
- Author
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Zhai, Ruocheng, Poleski, Radosław, Zang, Weicheng, Jung, Youn Kil, Udalski, Andrzej, Kuang, Renkun, Albrow, Michael D., Chung, Sun-Ju, Gould, Andrew, Han, Cheongho, Hwang, Kyu-Ha, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Yang, Hongjing, Yee, Jennifer C., Cha, Sang-Mok, Kim, Dong-Jin, Kim, Hyoun-Woo, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Skowron, Jan, Szymański, Michał K., Soszyński, Igor, Ulaczyk, Krzysztof, Pietrukowicz, Paweł, Kozłowski, Szymon, Mróz, Przemek, Rybicki, Krzysztof A., Iwanek, Patryk, Wrona, Marcin, Gromadzki, Mariusz, Wang, Hanyue, Mao, Shude, Zhang, Jiyuan, Qian, Qiyue, and Zhu, Wei
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
The gravitational microlensing technique is most sensitive to planets in a Jupiter-like orbit and has detected more than 200 planets. However, only a few wide-orbit ($s > 2$) microlensing planets have been discovered, where $s$ is the planet-to-host separation normalized to the angular Einstein ring radius, $\theta_{\rm E}$. Here we present the discovery and analysis of a strong candidate wide-orbit microlensing planet in the event, OGLE-2017-BLG-0448. The whole light curve exhibits long-term residuals to the static binary-lens single-source model, so we investigate the residuals by adding the microlensing parallax, microlensing xallarap, an additional lens, or an additional source. For the first time, we observe a complex degeneracy between all four effects. The wide-orbit models with $s \sim 2.5$ and a planet-to-host mass-ratio of $q \sim 10^{-4}$ are significantly preferred, but we cannot rule out the close models with $s \sim 0.35$ and $q \sim 10^{-3}$. A Bayesian analysis based on a Galactic model indicates that, despite the complicated degeneracy, the surviving wide-orbit models all contain a super-Earth-mass to Neptune-mass planet at a projected planet-host separation of $\sim 6$ au and the surviving close-orbit models all consist of a Jovian-mass planet at $\sim 1$ au. The host star is probably an M or K dwarf. We discuss the implications of this dimension-degeneracy disaster on microlensing light-curve analysis and its potential impact on statistical studies., Comment: submitted to AJ
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- 2023
35. OGLE-2019-BLG-1180Lb: Discovery of a Wide-orbit Jupiter-mass Planet around a Late-type Star
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Chung, Sun-Ju, Udalski, Andrzej, Yee, Jennifer C., Gould, Andrew, Albrow, Michael D., Jung, Youn Kil, Hwang, Kyu-Ha, Han, Cheongho, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Yang, Hongjing, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Poleski, Radek, Mróz, Przemek, Skowron, Jan, Szymański, Michał K., Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Ulaczyk, Krzysztof, Rybicki, Krzysztof A., Iwanek, Patryk, Wrona, Marcin, and Gromadzki, Mariusz
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Astrophysics - Earth and Planetary Astrophysics - Abstract
We report on the discovery and analysis of the planetary microlensing event OGLE-2019-BLG-1180 with a planet-to-star mass ratio $q \sim 0.003$. The event OGLE-2019-BLG-1180 has unambiguous cusp-passing and caustic-crossing anomalies, which were caused by a wide planetary caustic with $s \simeq 2$, where $s$ is the star-planet separation in units of the angular Einstein radius $\theta_{E}$. Thanks to well-covered anomalies by the Korea Micorolensing Telescope Network (KMTNet), we measure both the angular Einstein radius and the microlens parallax in spite of a relatively short event timescale of $t_{E} = 28$ days. However, because of a weak constraint on the parallax, we conduct a Bayesian analysis to estimate the physical lens parameters. We find that the lens system is a super-Jupiter-mass planet of $M_{p} = 1.75^{+0.54}_{-0.51} M_{J}$ orbiting a late-type star of $M_{h}=0.55^{+0.27}_{-0.26} M_\odot$ at a distance of $D_{L} = 6.1^{+0.9}_{-1.3}$ kpc. The projected star-planet separation is $a_{\perp} = 5.19^{+0.90}_{-1.23}$ au, which means that the planet orbits at about four times the snow line of the host star. Considering the relative lens-source proper motion of $\mu_{rel} = 6$ mas/yr, the lens will be separated from the source by 60 mas in 2029. At that time one can measure the lens flux from adaptive optics imaging of Kec or a next-generation 30 m class telescope. OGLE-2019-BLG-1180Lb represents a growing population of wide-orbit planets detected by KMTNet, so we also present a general investigation into prospects for further expanding the sample of such planets., Comment: 12 pages, 12 figures, 5 tables, published in AJ
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- 2023
36. KMT-2023-BLG-1431Lb: A New $q < 10^{-4}$ Microlensing Planet from a Subtle Signature
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Bell, Aislyn, Zhang, Jiyuan, Jung, Youn Kil, Yee, Jennifer C., Yang, Hongjing, Sumi, Takahiro, Udalski, Andrzej, Albrow, Michael D., Chung, Sun-Ju, Gould, Andrew, Han, Cheongho, Hwang, Kyu-Ha, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Zang, Weicheng, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Tang, Yunyi, McCormick, Jennie, Dong, Subo, Liu, Zhuokai, Mao, Shude, Maoz, Dan, Zhu, Wei, Abe, Fumio, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Bond, Ian A., Fujii, Hirosane, Fukui, Akihiko, Hamada, Ryusei, Hirao, Yuki, Silva, Stela Ishitani, Itow, Yoshitaka, Kirikawa, Rintaro, Kondo, Iona, Koshimoto, Naoki, Matsubara, Yutaka, Matsumoto, Sho, Miyazaki, Shota, Muraki, Yasushi, Okamura, Arisa, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Suzuki, Daisuke, Toda, Taiga, Tomoyoshi, Mio, Tristram, Paul J., Vandorou, Aikaterini, Yama, Hibiki, Yamashita, Kansuke, Mróz, Przemek, Skowron, Jan, Poleski, Radoslaw, Szymański, Michał K., Soszyński, Igor, Pietrukowicz, Paweł, Kozłowski, Szymon, Ulaczyk, Krzysztof, Rybicki, Krzysztof A., Iwanek, Patryk, Wrona, Marcin, and Gromadzki, Mariusz
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Solar and Stellar Astrophysics - Abstract
The current studies of microlensing planets are limited by small number statistics. Follow-up observations of high-magnification microlensing events can efficiently form a statistical planetary sample. Since 2020, the Korea Microlensing Telescope Network (KMTNet) and the Las Cumbres Observatory (LCO) global network have been conducting a follow-up program for high-magnification KMTNet events. Here, we report the detection and analysis of a microlensing planetary event, KMT-2023-BLG-1431, for which the subtle (0.05 magnitude) and short-lived (5 hours) planetary signature was characterized by the follow-up from KMTNet and LCO. A binary-lens single-source (2L1S) analysis reveals a planet/host mass ratio of $q = (0.72 \pm 0.07) \times 10^{-4}$, and the single-lens binary-source (1L2S) model is excluded by $\Delta\chi^2 = 80$. A Bayesian analysis using a Galactic model yields estimates of the host star mass of $M_{\rm host} = 0.57^{+0.33}_{-0.29}~M_\odot$, the planetary mass of $M_{\rm planet} = 13.5_{-6.8}^{+8.1}~M_{\oplus}$, and the lens distance of $D_{\rm L} = 6.9_{-1.7}^{+0.8}$ kpc. The projected planet-host separation of $a_\perp = 2.3_{-0.5}^{+0.5}$ au or $a_\perp = 3.2_{-0.8}^{+0.7}$, subject to the close/wide degeneracy. We also find that without the follow-up data, the survey-only data cannot break the degeneracy of central/resonant caustics and the degeneracy of 2L1S/1L2S models, showing the importance of follow-up observations for current microlensing surveys., Comment: PASP submitted. arXiv admin note: text overlap with arXiv:2301.06779
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- 2023
37. RepQ: Generalizing Quantization-Aware Training for Re-Parametrized Architectures
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Prutianova, Anastasiia, Zaytsev, Alexey, Lee, Chung-Kuei, Sun, Fengyu, and Koryakovskiy, Ivan
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Computer Science - Machine Learning - Abstract
Existing neural networks are memory-consuming and computationally intensive, making deploying them challenging in resource-constrained environments. However, there are various methods to improve their efficiency. Two such methods are quantization, a well-known approach for network compression, and re-parametrization, an emerging technique designed to improve model performance. Although both techniques have been studied individually, there has been limited research on their simultaneous application. To address this gap, we propose a novel approach called RepQ, which applies quantization to re-parametrized networks. Our method is based on the insight that the test stage weights of an arbitrary re-parametrized layer can be presented as a differentiable function of trainable parameters. We enable quantization-aware training by applying quantization on top of this function. RepQ generalizes well to various re-parametrized models and outperforms the baseline method LSQ quantization scheme in all experiments., Comment: BMVC 2023 (Oral)
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- 2023
38. Systematic Reanalysis of KMTNet microlensing events, Paper I: Updates of the Photometry Pipeline and a New Planet Candidate
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Yang, Hongjing, Yee, Jennifer C., Hwang, Kyu-Ha, Qian, Qiyue, Bond, Ian A., Gould, Andrew, Hu, Zhecheng, Zhang, Jiyuan, Mao, Shude, Zhu, Wei, Albrow, Michael D., Chung, Sun-Ju, Han, Cheongho, Jung, Youn Kil, Ryu, Yoon-Hyun, Shin, In-Gu, Shvartzvald, Yossi, Cha, Sang-Mok, Kim, Dong-Jin, Kim, Hyoun-Woo, Kim, Seung-Lee, Lee, Chung-Uk, Lee, Dong-Joo, Lee, Yongseok, Park, Byeong-Gon, Pogge, Richard W., Zang, Weicheng, Abe, Fumio, Barry, Richard, Bennett, David P., Bhattacharya, Aparna, Donachie, Martin, Fujii, Hirosane, Fukui, Akihiko, Hirao, Yuki, Itow, Yoshitaka, Kirikawa, Rintaro, Kondo, Iona, Koshimoto, Naoki, Li, Man Cheung Alex, Matsubara, Yutaka, Muraki, Yasushi, Miyazaki, Shota, Olmschenk, Greg, Ranc, Clément, Rattenbury, Nicholas J., Satoh, Yuki, Shoji, Hikaru, Silva, Stela Ishitani, Sumi, Takahiro, Suzuki, Daisuke, Tanaka, Yuzuru, Tristram, Paul J., Yamawaki, Tsubasa, and Yonehara, Atsunori
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Astrophysics - Earth and Planetary Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Solar and Stellar Astrophysics - Abstract
In this work, we update and develop algorithms for KMTNet tender-love care (TLC) photometry in order to create an new, mostly automated, TLC pipeline. We then start a project to systematically apply the new TLC pipeline to the historic KMTNet microlensing events, and search for buried planetary signals. We report the discovery of such a planet candidate in the microlensing event MOA-2019-BLG-421/KMT-2019-BLG-2991. The anomalous signal can be explained by either a planet around the lens star or the orbital motion of the source star. For the planetary interpretation, despite many degenerate solutions, the planet is most likely to be a Jovian planet orbiting an M or K dwarf, which is a typical microlensing planet. The discovery proves that the project can indeed increase the sensitivity of historic events and find previously undiscovered signals., Comment: 19 pages, 13 figures, 7 tables. Submitted to MNRAS
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- 2023
39. Last-Iterate Convergence Properties of Regret-Matching Algorithms in Games
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Cai, Yang, Farina, Gabriele, Grand-Clément, Julien, Kroer, Christian, Lee, Chung-Wei, Luo, Haipeng, and Zheng, Weiqiang
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Computer Science - Computer Science and Game Theory ,Computer Science - Machine Learning - Abstract
Algorithms based on regret matching, specifically regret matching$^+$ (RM$^+$), and its variants are the most popular approaches for solving large-scale two-player zero-sum games in practice. Unlike algorithms such as optimistic gradient descent ascent, which have strong last-iterate and ergodic convergence properties for zero-sum games, virtually nothing is known about the last-iterate properties of regret-matching algorithms. Given the importance of last-iterate convergence for numerical optimization reasons and relevance as modeling real-word learning in games, in this paper, we study the last-iterate convergence properties of various popular variants of RM$^+$. First, we show numerically that several practical variants such as simultaneous RM$^+$, alternating RM$^+$, and simultaneous predictive RM$^+$, all lack last-iterate convergence guarantees even on a simple $3\times 3$ game. We then prove that recent variants of these algorithms based on a smoothing technique do enjoy last-iterate convergence: we prove that extragradient RM$^{+}$ and smooth Predictive RM$^+$ enjoy asymptotic last-iterate convergence (without a rate) and $1/\sqrt{t}$ best-iterate convergence. Finally, we introduce restarted variants of these algorithms, and show that they enjoy linear-rate last-iterate convergence.
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- 2023
40. Gravitational-wave Electromagnetic Counterpart Korean Observatory (GECKO): GECKO Follow-up Observation of GW190425
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Paek, Gregory S. H., Im, Myungshin, Kim, Joonho, Lim, Gu, Park, Bomi, Choi, Changsu, Kim, Sophia, Barbieri, Claudio, Salafia, Om Sharan, Paek, Insu, Shin, Suhyun, Seo, Jinguk, Lee, Hyung Mok, Lee, Chung-Uk, Kim, Seung-Lee, and Sung, Hyun-Il
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
One of the keys to the success of multimessenger astronomy is the rapid identification of the electromagnetic wave counterpart, kilonova (KN), of the gravitational-wave (GW) event. Despite its importance, it is hard to find a KN associated with a GW event, due to a poorly constrained GW localization map and numerous signals that could be confused as a KN. Here, we present the Gravitational-wave Electromagnetic wave Counterpart Korean Observatory (GECKO) project, the GECKO observation of GW190425, and prospects of GECKO in the fourth observing run (O4) of the GW detectors. We outline our follow-up observation strategies during O3. In particular, we describe our galaxy-targeted observation criteria that prioritize based on galaxy properties. Armed with this strategy, we performed an optical and/or near-infrared follow-up observation of GW190425, the first binary neutron star merger event during the O3 run. Despite a vast localization area of 7460 deg^2, we observed 621 host galaxy candidates, corresponding to 29.5% of the scores we assigned, with most of them observed within the first 3 days of the GW event. Ten transients were discovered during this search, including a new transient with a host galaxy. No plausible KN was found, but we were still able to constrain the properties of potential KNe using upper limits. The GECKO observation demonstrates that GECKO can possibly uncover a GW170817-like KN at a distance less than 200 Mpc if the localization area is of the order of hundreds of square degrees, providing a bright prospect for the identification of GW electromagnetic wave counterparts during the O4 run., Comment: 35 pages, 19 figures Accepted for publication in ApJ
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- 2023
41. UCHL1 is a potential molecular indicator and therapeutic target for neuroendocrine carcinomas.
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Liu, Shiqin, Chai, Timothy, Garcia-Marques, Fernando, Yin, Qingqing, Hsu, En-Chi, Shen, Michelle, Shaw Toland, Angus, Bermudez, Abel, Hartono, Alifiani, Massey, Christopher, Lee, Chung, Zheng, Liwei, Baron, Maya, Denning, Caden, Aslan, Merve, Nguyen, Holly, Zoubeidi, Amina, Das, Millie, Kunder, Christian, Howitt, Brooke, Soh, H, Weissman, Irving, Liss, Michael, Chin, Arnold, Brooks, James, Corey, Eva, Pitteri, Sharon, Huang, Jiaoti, Nolley, Rosie, and Stoyanova, Tanya
- Subjects
UCHL1 ,neuroblastoma ,neuroendocrine carcinomas ,neuroendocrine prostate cancer ,nuclear pore complex ,small cell lung cancer ,Male ,Humans ,Ubiquitin Thiolesterase ,Carcinoma ,Neuroendocrine ,Small Cell Lung Carcinoma ,Lung Neoplasms ,Membrane Glycoproteins - Abstract
Neuroendocrine carcinomas, such as neuroendocrine prostate cancer and small-cell lung cancer, commonly have a poor prognosis and limited therapeutic options. We report that ubiquitin carboxy-terminal hydrolase L1 (UCHL1), a deubiquitinating enzyme, is elevated in tissues and plasma from patients with neuroendocrine carcinomas. Loss of UCHL1 decreases tumor growth and inhibits metastasis of these malignancies. UCHL1 maintains neuroendocrine differentiation and promotes cancer progression by regulating nucleoporin, POM121, and p53. UCHL1 binds, deubiquitinates, and stabilizes POM121 to regulate POM121-associated nuclear transport of E2F1 and c-MYC. Treatment with the UCHL1 inhibitor LDN-57444 slows tumor growth and metastasis across neuroendocrine carcinomas. The combination of UCHL1 inhibitors with cisplatin, the standard of care used for neuroendocrine carcinomas, significantly delays tumor growth in pre-clinical settings. Our study reveals mechanisms of UCHL1 function in regulating the progression of neuroendocrine carcinomas and identifies UCHL1 as a therapeutic target and potential molecular indicator for diagnosing and monitoring treatment responses in these malignancies.
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- 2024
42. Influence of Region-Specific Marine Environments on Phytoplankton and Bacterial Communities in the Korean Coastal Waters in Winter 2021
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Lim, Young Kyun, Hong, Seongjin, Lee, Chung Hyeon, Kim, Mungi, and Baek, Seung Ho
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- 2024
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43. Nanomechanical thermometry for probing sub-nW thermal transport
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Oh, Sangmin, Shekhawat, Nehpal Singh, Jameel, Osama, Lal, Amit, and Lee, Chung Hoon
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- 2024
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44. Reconstruction of the Temperature Index Series of China in 1368–1911 based on REACHES database
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Wang, Pao K., Lin, Kuan-Hui Elaine, Lin, Yu-Shiuan, Lin, Ho-Jiunn, Pai, Pi-Ling, Tseng, Wan-Ling, Huang, Hsin-Cheng, and Lee, Chung-Rui
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- 2024
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45. Breaking the board: the rise of female Go players in Korea
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Kang, Jimoon, Song, Hyeryung, Kim, Seongcheol, Lee, Chung Gun, and Kim, Kihan
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- 2024
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46. Applying a deterrence nudge strategy for promoting stair usage in a university setting
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Lee, Chung Gun, Chu, Jiyeon, Mao, Ruoqi, Kim, Hansol, Lee, Eun-Young, Park, Seiyeong, and Kim, Taeeung
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- 2024
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47. Potentiating effect of AMD3100 on bone morphogenetic protein-2 induced bone regeneration
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Shim, Gyu-Jo, Lee, Chung O., Lee, Jung-Tae, Jung, Hong-Moon, and Kwon, Tae-Geon
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- 2024
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48. Histopathologic image–based deep learning classifier for predicting platinum-based treatment responses in high-grade serous ovarian cancer
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Ahn, Byungsoo, Moon, Damin, Kim, Hyun-Soo, Lee, Chung, Cho, Nam Hoon, Choi, Heung-Kook, Kim, Dongmin, Lee, Jung-Yun, Nam, Eun Ji, Won, Dongju, An, Hee Jung, Kwon, Sun Young, Shin, Su-Jin, Jung, Hye Ra, Kwon, Dohee, Park, Heejung, Kim, Milim, Cha, Yoon Jin, Park, Hyunjin, Lee, Yangkyu, Noh, Songmi, Lee, Yong-Moon, Choi, Sung-Eun, Kim, Ji Min, Sung, Sun Hee, and Park, Eunhyang
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- 2024
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49. Impact of insertion into the left internal jugular vein in chemoport-associated infections: a retrospective single-center study of 1690 cases
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Kim, Gwon-Min, Song, Seunghwan, Kim, Do Young, Kim, Soo Han, Lee, Chung Won, Bae, Miju, Kim, Jong Won, and Huh, Up
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- 2024
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50. Urinary cadmium concentration is associated with the severity and clinical outcomes of COVID-19: a bicenter observational cohort study
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Chiu, Li-Chung, Lee, Chung-Shu, Hsu, Ping-Chih, Li, Hsin-Hsien, Chan, Tien-Ming, Hsiao, Ching-Chung, Kuo, Scott Chih-Hsi, Ko, How-Wen, Lin, Shu-Min, Wang, Chun-Hua, Lin, Horng-Chyuan, Chu, Pao-Hsien, and Yen, Tzung-Hai
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- 2024
- Full Text
- View/download PDF
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