136 results on '"Oh, Se-Young"'
Search Results
2. Suppression of Leakage Currents in Photo-multiplication Photodetectors with Oxidation-Controlled Metal Interfacial Layer.
- Author
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Lim, Seong Bin, Lee, Ji-Young, Lim, Tae Hun, Lee, Seri, Lee, Seung Ho, Kim, Gyu Min, and Oh, Se Young
- Abstract
In this work, we investigate the use of annealed metal oxides in electron blocking layer (EBL) of photo-multiplication organic photodetectors (PM-OPD), to obtain low leakage current, high external quantum efficiency, and thereby, high detectivity. Reliable and high-performance PM-OPD are obtained using multi-interfacial EBLs composed of metals such as Ni, Al, Ag and Au, and their oxides, through a controlled annealing. The interfacial layer between the front electrode and absorption layer is metal–metal oxide layer with wide bandgap, for improved hole mobility and stable electron blocking under the driving voltages of the PM-OPD. Through the optimization of the structural stability of the PM-OPD, a high specific detectivity of 2.59 × 10
13 Jones is obtained under a low reverse voltage. The resulting photodetectors exhibit improved stability under relatively low reverse voltages because of the Schottky barrier induced between the donor and acceptor, electrode components, and passivation effect of the free-electrons driven by the introduced multi-interfacial layers. [ABSTRACT FROM AUTHOR]- Published
- 2024
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- View/download PDF
3. CD49f and CD146: A Possible Crosstalk Modulates Adipogenic Differentiation Potential of Mesenchymal Stem Cells.
- Author
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Tran, An Nguyen-Thuy, Kim, Ha Yeong, Oh, Se-Young, and Kim, Han Su
- Subjects
ADIPOGENESIS ,MESENCHYMAL stem cell differentiation ,CELL differentiation ,MESENCHYMAL stem cells ,HIGH throughput screening (Drug development) - Abstract
Background: The lack of appropriate mesenchymal stem cells (MSCs) selection methods has given the challenges for standardized harvesting, processing, and phenotyping procedures of MSCs. Genetic engineering coupled with high-throughput proteomic studies of MSC surface markers arises as a promising strategy to identify stem cell-specific markers. However, the technical limitations are the key factors making it less suitable to provide an appropriate starting material for the screening platform. A more accurate, easily accessible approach is required to solve the issues. Methods: This study established a high-throughput screening strategy with forward versus side scatter gating to identify the adipogenesis-associated markers of bone marrow-derived MSCs (BMSCs) and tonsil-derived MSCs (TMSCs). We classified the MSC-derived adipogenic differentiated cells into two clusters: lipid-rich cells as side scatter (SSC)-high population and lipid-poor cells as SSC-low population. By screening the expression of 242 cell surface proteins, we identified the surface markers which exclusively found in lipid-rich subpopulation as the specific markers for BMSCs and TMSCs. Results: High-throughput screening of the expression of 242 cell surface proteins indicated that CD49f and CD146 were specific for BMSCs and TMSCs. Subsequent immunostaining confirmed the consistent specific expression of CD49f and CD146 and in BMSCs and TMSCs. Enrichment of MSCs by CD49f and CD146 surface markers demonstrated that the simultaneous expression of CD49f and CD146 is required for adipogenesis and osteogenesis of mesenchymal stem cells. Furthermore, the fate decision of MSCs from different sources is regulated by distinct responses of cells to differentiation stimulations despite sharing a common CD49f
+ CD146+ immunophenotype. Conclusions: We established an accurate, robust, transgene-free method for screening adipogenesis associated cell surface proteins. This provided a valuable tool to investigate MSC-specific markers. Additionally, we showed a possible crosstalk between CD49f and CD146 modulates the adipogenesis of MSCs. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. An Alternative to Chlorobenzene as a Hole Transport Materials Solvent for High-Performance Perovskite Solar Cells.
- Author
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Lee, Seung Ho, Lim, Seong Bin, Kim, Jin Young, Lee, Seri, Oh, Se Young, and Kim, Gyu Min
- Subjects
SOLAR cells ,CHLOROBENZENE ,PEROVSKITE ,OPEN-circuit voltage ,HOLE mobility ,POLYANILINES ,DICHLOROMETHANE - Abstract
Spiro-OMeTAD is a widely used hole-transporting layer (HTL) material, characterized by high hole mobility and good film-forming properties, in perovskite solar cells (PSCs). However, this material has high synthesis costs, low solubility, dependence on hygroscopic dopants, and a low commercial potential. Recently, we investigated alternative materials with good solubility, simple synthetic methods, and good electrical characteristics for use as hole transport materials (HTM) in triple-cation PSCs. Herein, (E,E,E,E)-4,4′,4″,4′″-[Benzene-1,2,4,5-tetrayltetrakis(ethene-2,1-diyl)]tetrakis[N,N-bis(4-methoxyphenyl)aniline], which has a small molecular weight and similar properties to Spiro-OMeTAD, was assessed for use as a HTM via a pre-test of device performance, including its electrical properties, surface morphology, and coating process method, with PSC efficiencies routinely surpassing 20%. A remarkable open-circuit voltage of 1.111, along with a photovoltaic efficiency of 20.18% was obtained in PSCs using this HTM with dichloromethane (DCM) instead of chlorobenzene, indicative of its potential for the fabrication of resistance components with improved surface uniformity. These results provide insights into DCM as an efficient solvent for small molecule-based HTM. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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5. Physical Effects of 2PACz Layers as Hole-Transport Material on the Performance of Perovskite Solar Cell.
- Author
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Kim, Doo-Hwan, Lee, Seri, Kim, Gyu Min, and Oh, Se Young
- Abstract
Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT: PSS) is widely used as a hole-transport layer (HTL) in perovskite solar cells (PSCs) with inverted (p-i-n) structures. However, problems associated with the corrosivity of PEDOT:PSS prevent the commercialization of such PSCs. To solve this problem, we fabricated inverted PSCs using [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (2PACz) as HTL. We used a mixture of N-methyl-2-pyrrolidone and N, N-dimethylformamide in the perovskite precursor, which reduced the amount of the antisolvent chlorobenzene. We investigated the physical effects of the amount of antisolvent used. In addition, we suggest a method to improve the performance of inverted PSCs using 2PACz as the HTL, thereby achieving higher performance. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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6. Degradation Mechanism of Phenethylamine‐Based Interlayers in Perovskite Solar Cells and Breakthrough.
- Author
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Lee, Seri, Kim, Gyu Min, Miyasaka, Tsutomu, and Oh, Se Young
- Abstract
Phenethylamine (PEA) halides (X) coated on perovskite (PVK) films are widely known as passivating layers, resulting in high performance in perovskite solar cells (PSCs). However, critical stability issues associated with phenethylamine halides (PEAX) in PSCs are observed, especially with Spiro‐OMeTAD, which prevented its practical use. Here, the mechanism by which PEAX negatively affects PSCs is reported. In addition, a method is devised to overcome the stability issue by employing poly(methyl methacrylate) (PMMA) at the PVK/PEABr interface to form dual PMMA/PEABr interlayers. Contrary to the general use of PEABr, the indirect contact of PEABr with PVK films by PMMA resulted in superior power conversion efficiencies (PCEs) and enhanced stability resulting from the retention of dipole moments even under aging. Further, effective methods of maximizing and retaining the dipole effect by heating PMMA/PEAX, as opposed to PSCs incorporating PEAX without PMMA being negatively affected by heat are exploited. The resulting PSCs with PMMA/heated PEABr exhibit a PCE of 21.63%, and retain 95% of their original performance a month after fabrication. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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7. Oleracone F Alleviates Cognitive Impairment and Neuropathology in APPswe/PSEN1dE9 Mice by Reducing the Expression of Vascular Cell Adhesion Molecule and Leukocyte Adhesion to Brain Vascular Endothelial Cells.
- Author
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Kwon, Young-Sun, Ko, Jin-Sung, Oh, Se-Young, Han, Young Taek, and Jo, Sangmee Ahn
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CELL adhesion molecules ,VASCULAR endothelial cells ,COGNITION disorders ,AMYLOID beta-protein precursor ,VASCULAR cell adhesion molecule-1 ,NEUROFIBRILLARY tangles ,CELL adhesion - Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease and the blood–brain barrier dysfunction has been suggested as a key pathological feature of the disease. Our research group successfully established a synthetic protocol for oleracones, a novel series of flavonoids isolated from the plant extract of Portulaca oleracea L. (PO). PO extract was reported to have anti-inflammatory and antioxidant effects, enhancing cognitive function. Thus, we investigated the effects and mechanism of oleracones on cognition using AD model transgenic mice (Tg; APPswe/PSEN1dE9). Oleracone F treatment significantly improved memory dysfunction in Tg mice. Oleracone F decreased the number, burden, and immunoreactivity of amyloid plaques and amyloid precursor protein (APP) protein levels in the brains of Tg mice compared to wild-type mice. Oleracone F also alleviated inflammation observed in Tg mice brains. In vitro studies in human microvascular endothelial cells (HBMVECs) demonstrated that oleracones D, E, and F blocked the elevations in VCAM-1 protein induced by tumor necrosis factor-α (TNF-α), hindering leukocyte adhesion to HBMVECs. Taken together, our results suggest that oleracones ameliorated cognitive impairment by blocking TNF-α-induced increases in VCAM-1, thereby reducing leukocyte infiltration to the brain and modulating brain inflammation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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8. Basic Fibroblast Growth Factor Induces Cholinergic Differentiation of Tonsil-Derived Mesenchymal Stem Cells.
- Author
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Song, Ji-Hye, Oh, Se-Young, and Jo, Sangmee Ahn
- Published
- 2022
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9. Modeling of a methanol synthesis process to utilize CO2 in the exhaust gas from an engine plant.
- Author
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Jeong, Jae Hun, Kim, Yoori, Oh, Se-Young, Park, Myung-June, and Lee, Won Bo
- Abstract
We investigated the conversion of CO
2 in the exhaust gas of an engine plant into methanol. The process consists of CO2 purification by an acid gas removal unit (AGRU), mixed reforming, and methanol synthesis. The AGRU removes a large amount of inert gas, yielding CO2 of 98% purity at a recovery rate of 90% for use as feed to the reformer. The reformer temperature of 900 °C led to the almost total consumption of CH4. In the methanol synthesis reaction, the utility temperature had a greater influence on the conversion and methanol production rate than the inlet temperature. The optimal temperature was determined as 180 °C. Because the amount of hydrogen in the reformer effluent produced by dry reforming was insufficient, the steam available in the engine plant was used for mixed (dry and steam) reforming. The steam increased the hydrogen and methanol production rate; however, the compression cost was too high, and there exists an optimal amount of steam in the feed. The techno-economic analysis of the optimal conditions showed that utilization of CO2 in the exhaust gas along with freely available steam is economically feasible and reduces CO2 emissions by over 85%. [ABSTRACT FROM AUTHOR]- Published
- 2022
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10. Characteristics and Fabrication of an Inverted Organic Photodiode Using CdSe Core/ZnS Shell Quantum Dots As an Electron Transport Material.
- Author
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Lee, Seri, Kim, Gyu Min, Kim, Kee-Tae, Kim, Woo-Seong, and Oh, Se-Young
- Subjects
QUANTUM dots ,BUFFER layers ,ZINC sulfide ,ELECTRON transport ,QUANTUM dot devices ,BAND gaps ,STRAY currents - Abstract
To achieve high detectivity of organic photodetectors (OPDs), we incorporated CdSe core/ZnS shell quantum dots (CdSe@ZnS) in devices consisting of ITO/tin oxide (SnO
2 )/CdSe@ZnS/(poly(3-hexylthiophene-2,5-diyl)[P3HT]:PC60 BM)/MoO3 /Ag. We found that the CdSe@ZnS layer has a significant role in enhancing photocurrent and reducing leakage current simultaneously by transferring energy from the quantum dot buffer layer to the wide band gap of the ZnS shell. As a result, the device with the CdSe@ZnS quantum dot buffer layer shows enhancement of the photocurrent by 13.2%, reduction in the dark current from 8.28 µA/cm2 to 1.06 µA/cm2 , and detectivity of 1.43 × 1012 Jones. [ABSTRACT FROM AUTHOR]- Published
- 2022
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11. A Distortion Model of Laser Sheet for a Laser Line Scanner With Large Fan Angle.
- Author
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Yoon, Seongwon, Son, Youngbin, Oh, Se-young, and Han, Soohee
- Subjects
GEOMETRICAL optics ,LASERS ,DEPTH perception ,OPTICAL scanners ,LASER beams - Abstract
This article proposes an analytical method of computing distorted laser sheet of a laser line scanner and compensating it. In this article, a distortion model of laser sheet generated from a laser line scanner with large fan angle is derived from physical principles to achieve accurate depth perception even around its edges on which significant depth estimation errors occur in existing algorithms. From a laser beam incident obliquely on a contact surface of two cylindrical lenses, a curved laser sheet is expressed in terms of the nonzero incident angle by the laws of geometrical optics. From the mathematical model of the distorted laser sheet, the incident angle is estimated through an optimization technique and then its estimate is used for depth computation. It is shown through simulations and experiments that the proposed distortion model enables a proper compensation scheme and hence the distortion-compensated depth estimation errors are reduced all over the range of interest, specially much around the both side edges of the laser sheet. Quantitatively in comparison to the compensation-free method, the depth estimation error is improved from 225 to 28 mm on average and from 1781 to 187 mm for worst-case scenarios near edges of a laser sheet. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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12. Optimization of Microenvironments Inducing Differentiation of Tonsil-Derived Mesenchymal Stem Cells into Endothelial Cell-Like Cells.
- Author
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Oh, Se-Young, Choi, Da Hyeon, Jin, Yoon Mi, Yu, Yeonsil, Kim, Ha Yeong, Kim, Gyungah, Park, Yoon Shin, and Jo, Inho
- Published
- 2019
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13. P3HT-based visible-light organic photodetectors using PEI/PAA multilayers as a p-type buffer layer.
- Author
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Ji, Chan Hyuk, Lee, Seon Ju, and Oh, Se Young
- Published
- 2019
- Full Text
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14. Enhanced photocurrent in organic photodetectors by the tunneling effect of a hafnium oxide thin film as an electron blocking layer.
- Author
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Ji, Chan Hyuk, Lee, Ji Young, Kim, Kee Tae, and Oh, Se Young
- Published
- 2019
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15. Effect of lipopolysaccharide-induced immune stimulation and maternal fish oil and microalgae supplementation during late pregnancy on nursery pig hypothalamic–pituitary–adrenal function 1.
- Author
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You, Lan, Lee, Alison V, Oh, Se-Young, Fisher-Heffernan, Rebecca E, Edwards, Michelle, Lange, Kees de, and Karrow, Niel A
- Subjects
FISH oils ,HYPOTHALAMIC-pituitary-adrenal axis ,PREGNANCY ,PLANT nurseries ,DIETARY supplements ,THERAPEUTICS - Abstract
The present study used Escherichia coli lipopolysaccharide (LPS) to investigate whether maternal immune challenge during late gestation altered programming of the offspring hypothalamus and hypothalamic–pituitary–adrenal axis (HPAA). In addition, interactions of maternal diet, supplementation with fish oil (FO) or microalgae (AL), and complex vs. simple weaning diets were investigated. Briefly, Landrace × Yorkshire sows (N = 48) were randomly assigned to diets supplemented with FO, AL, or a standard gestation control diet (CON) from day 75 of gestation (gd 75) until parturition. On gd 112, half the sows from each dietary treatment were immune challenged with LPS (10 μg/kg BW) or saline as a control. At 21 d postpartum, the offspring were weaned, and half the animals from each maternal treatment were allocated to either a complex or simple weaning diet. At 28 d postpartum, the offspring's hourly fever and 2-h cortisol responses to LPS immune challenge (40 μg/kg BW) were measured to assess hypothalamus and HPAA function. Results indicated that the maternal temperature of sows on the FO diet returned to baseline levels faster than sows on the AL and CON diets after LPS immune challenge (P < 0.05). In contrast, there was no difference in the maternal cortisol response across the dietary treatments (P > 0.10). Regardless of the dietary treatments, the maternal LPS immune challenge induced a greater cortisol response in male offspring (P = 0.05) and a greater fever response in female offspring (P = 0.03) when they were LPS immune challenged post-weaning. Male offspring from LPS-immune-challenged sows fed the FO and AL diets had a greater fever response than male offspring from the maternal CON diet group (P ≤ 0.05). Last, no effect of the complex or simple weaning diets was observed for the nursery pig cortisol or fever responses to LPS immune challenge. In conclusion, LPS immune challenge during late pregnancy altered responsiveness of the offspring hypothalamus and HPAA to this same microbial stressor, and a sex-specific response was influenced by maternal dietary supplementation with FO and AL. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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16. Influence of vitamin B deficiency on PM2.5-induced cardiac autonomic dysfunction.
- Author
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Lim, Youn-Hee, Park, Hye Yin, Yi, Seung-Muk, Park, EunHa, Lee, Bo-Eun, Oh, Se-Young, and Hong, Yun-Chul
- Published
- 2020
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17. Effect of dietary patterns on the blood/urine concentration of the selected toxic metals (Cd, Hg, Pb) in Korean children.
- Author
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Yoo, Byoung-Wook, Kim, Bom, Joshi, Pankaj, Kwon, Sung-Ok, Kim, YeonJin, Oh, Jung-Sook, Kim, Jeongseon, Oh, Se-Young, Lim, Ji-Ae, Choi, Byung-Sun, Kim, Yu-Mi, Eom, Sang-Yong, Hong, Young-Seob, Sohn, Seok-Joon, Park, Kyung-Su, Pyo, Heesoo, Kim, Ho, Ha, Mina, Park, Jung-Duck, and Kwon, Ho-Jang
- Abstract
This study was aimed to examine the association the blood/urinary concentration of toxic metal (Hg, Pb, and Cd) with children’s dietary patterns. This cross-sectional study included 1026 school children aged 8-17 years. Dietary patterns were defined using factor loading scores for 108 foods from a Semi-Quantitative Food Frequency Questionnaire. A high blood Hg level was found in boys with a high score in the ‘fish’ pattern (p = 0.02), and in girls with a high score in ‘fruit’ pattern (p = 0.04). The concentration of Pb was related to the ‘imprudent’ pattern in high school boys (p = 0.02). The effect of the ‘vegetable’ pattern on high excretion of urinary Cd was observed in low grade elementary (p = 0.04) and middle school students (p < 0.0001), and the effect of the ‘fruit’ pattern on the urinary Cd was observed in high grade elementary school students (p = 0.02). This study suggests that the concentration of selected toxic metals in blood/urine could be affected by children’s dietary pattern. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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18. Estimation model for habitual 24-hour urinary-sodium excretion using simple questionnaires from normotensive Koreans.
- Author
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Kong, Ji-Sook, Lee, Yeon-Kyung, Kim, Mi Kyung, Choi, Mi-Kyeong, Heo, Young-Ran, Hyun, Taisun, Kim, Sun Mee, Lyu, Eun-Soon, Oh, Se-Young, Park, Hae-Ryun, Rhee, Moo-Yong, Ro, Hee-Kyong, and Song, Mi Kyung
- Subjects
URINATION ,SODIUM in the body ,REGRESSION analysis ,BODY weight ,STEWS ,BLAND-Altman plot - Abstract
This study was conducted to develop an equation for estimation of 24-h urinary-sodium excretion that can serve as an alternative to 24-h dietary recall and 24-h urine collection for normotensive Korean adults. In total, data on 640 healthy Korean adults aged 19 to 69 years from 4 regions of the country were collected as a training set. In order to externally validate the equation developed from that training set, 200 subjects were recruited independently as a validation set. Due to heterogeneity by gender, we constructed a gender-specific equation for estimation of 24-h urinary-sodium excretion by using a multivariable linear regression model and assessed the performance of the developed equation in validation set. The best model consisted of age, body weight, dietary behavior (‘eating salty food’, ‘Kimchi consumption’, ‘Korean soup or stew consumption’, ‘soy sauce or red pepper paste consumption’), and smoking status in men, and age, body weight, dietary behavior (‘salt preference’, ‘eating salty food’, ‘checking sodium content for processed foods’, ‘nut consumption’), and smoking status in women, respectively. When this model was tested in the external validation set, the mean bias between the measured and estimated 24-h urinary-sodium excretion from Bland-Altman plots was -1.92 (95% CI: -113, 110) mmol/d for men and -1.51 (95% CI: -90.6, 87.6) mmol/d for women. The cut-points of sodium intake calculated based on the equations were ≥4,000 mg/d for men and ≥3,500 mg/d for women, with 89.8 and 76.6% sensitivity and 29.3 and 64.2% specificity, respectively. In this study, a habitual 24-hour urinary-sodium-excretion-estimation model of normotensive Korean adults based on anthropometric and lifestyle factors was developed and showed feasibility for an asymptomatic population. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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19. Studies on the fabrication and characteristics of photoelectrochemical cells using IrO2-coated TiO2 photoanode for Z-scheme water splitting and perovskite solar cell bias.
- Author
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Lee, Ji-Young, Kim, Kee-Tae, Park, Ji Hun, and Oh, Se Young
- Subjects
FABRICATION (Manufacturing) ,PHOTOELECTROCHEMICAL cells ,SOLAR cells ,PEROVSKITE ,ANODES - Abstract
In the present work, to build a water splitting system using only a neutral electrolyte solution and light source, we investigated the photoelectrochemical properties and interface resistances of an IrO
2 -coated TiO2 photoanode in Z-scheme configuration. The photoelectrochemical cell was connected to the perovskite solar cell with to realize the system with no need for an external electrical bias. Photoanodes with IrO2 were found to support hole transport and to reduce the overpotential, therefore increasing the current density of the system consisting of photoelectrochemical cells. A maximum solar-to-hydrogen efficiency of 8.2% was achieved in a neutral electrolyte. [ABSTRACT FROM AUTHOR]- Published
- 2018
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20. Studies on the fabrication and characteristics of organic photodiode using novel Ga-doped NiOx as an electron-blocking layer.
- Author
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Kim, Kee-Tae, Ji, Chan-Hyuk, Song, Da-Hee, Kim, Hae-Sung, and Oh, Se-Young
- Subjects
FABRICATION (Manufacturing) ,PHOTODIODES ,ELECTRONS ,METAL organic chemical vapor deposition ,DOPING agents (Chemistry) - Abstract
The photodiode converts incident light into a microcurrent that flows when photons of sufficient energy strike the device under reverse bias. In doing so, a leakage current is caused by the reverse bias. In order to decrease the leakage current, buffer layers are introduced as electron- and hole-blocking materials between the photoactive material and electrode. We fabricated an organic photodiode using Ga-doped NiO
x as an electron-blocking layer and investigated the physical effects of Ga doping on the performance of the organic photodiode. Our results showed that this diode exhibited high detectivity of 1.06 × 1012 Jones. [ABSTRACT FROM AUTHOR]- Published
- 2018
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21. Semi-rotation invariant feature descriptors using Zernike moments for MLP classifier.
- Author
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Yoon, YuBin, Lee, Lae-Kyoung, and Oh, Se-Young
- Published
- 2016
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22. Fast training of convolutional neural network classifiers through extreme learning machines.
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Yoo, Youngwoo and Oh, Se-Young
- Published
- 2016
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23. Preparation and characterization of electro-responsive core-sheath fiber mats for smart materials.
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Oh, Se Young and Kang, Tae Jin
- Subjects
MULTIWALLED carbon nanotubes ,ELECTROSPINNING ,SPINNING (Textiles) ,SMART materials ,TENSILE strength ,TEXTILES - Abstract
Multi-walled carbon nanotubes coated with inorganic materials were spun with polyethylene terephthalate with a core-sheath structure using co-axial electrospinning technique. The effect of electrorheological (ER) particle content on the morphology, rheological and mechanical properties has been studied. It has been shown that ER particles were homogeneously distributed throughout the core part of the fibers with the core-sheath structure. It has been uniformly fabricated by controlling the viscosity and conductivity of ER fluids as well as the applied voltage, feeding rate of the electrospinning systems. The tensile test results with fiber mats showed that the modulus and tensile strength of the fiber mats is enhanced with lower breaking elongation because of the instant increase of viscosity and yield stress of ER fluid in the core part under the external applied electric field. Fiber mats with ER fluids in the core of the fiber may find potential applications in the area of adaptive textile structures. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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24. Effect of prenatal antioxidant intake on infants' respiratory infection is modified by a CD14 polymorphism.
- Author
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Hong, Seo, Lee, Eun, Kwon, Sung, Kim, Kyung, Shin, Youn, Ahn, Kang, Kim, Eun-Jin, Lee, Jeom-Gyu, Oh, Se-Young, and Hong, Soo-Jong
- Abstract
Background: Prenatal maternal diet may influence disease susceptibility in offspring with specific genetic backgrounds. We hypothesized that interactions between prenatal antioxidant intake and polymorphisms in immunity genes influence respiratory tract infection (RTI) susceptibility in infants at 12 months of age. Methods: This study included 550 infants. In the Cohort for Childhood Origin of Asthma and Allergic Diseases (COCOA) birth cohort study, prenatal maternal diet was assessed by administering a food frequency questionnaire. Infants' cord blood was genotyped for CD14 (rs2569190), TLR4 (rs1927911), and GSDMB (rs4794820) polymorphisms by the TaqMan method. Results: Higher prenatal intake of total fruit and vegetables (FV) was associated with the decreased risk of RTI in offspring ( P-trend=0.0430). In children with TT genotype at rs2569190, a higher prenatal intake of vitamins A and C, fruits, and total FV decreased RTI risk ( P-trend <0.05), while in infants with TC+CC genotype, a higher prenatal intake of fruit increased RTI risk ( P-trend <0.05). When analyzing the 3 genotypes, children with TT genotype at rs2569190 were more protected against RTIs compared with those with CC genotype with respect to vitamin C and fruits [odds ratio (OR)=5.04 and OR=10.30, respectively]. In children with CC genotype at rs1927911, RTI risk showed a dose-response association with a higher prenatal intake of vitamin C ( P for interaction<0.05). A higher prenatal intake of fruits and total FV reduced RTI risk in infants with GA+AA genotype of rs4794820 ( P for interaction<0.05). Conclusions: Prenatal antioxidant intake may reduce RTI risk in infants and this relationship may be modified by CD14, TLR4, and GSDMB polymorphisms. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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25. Maternal Urinary Bisphenol A Concentration During Midterm Pregnancy and Children's Blood Pressure at Age 4.
- Author
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Sanghyuk Bae, Youn-Hee Lim, Young Ah Lee, Choong Ho Shin, Se-Young Oh, Yun-Chul Hong, Bae, Sanghyuk, Lim, Youn-Hee, Lee, Young Ah, Shin, Choong Ho, Oh, Se-Young, and Hong, Yun-Chul
- Published
- 2017
- Full Text
- View/download PDF
26. Structure-property relationship study of partially aliphatic copolyimides for preparation of flexible and transparent polyimide films.
- Author
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Yu, Hwan-Chul, Jung, Jae-Woo, Choi, Ju-Young, Oh, Se Young, and Chung, Chan-Moon
- Subjects
POLYIMIDE films ,PERMITTIVITY ,AROMATIC compounds ,ALIPHATIC compounds ,OPTICAL properties - Abstract
The structure-property relationship of partially aliphatic copolyimides has been studied for the development of flexible, transparent polyimide films. A structurally rigid cycloaliphatic dianhydride and three aromatic dianhydrides having different structural flexibility were reacted with 4,4′-oxydianiline to prepare the copolyimides. In order to control the balance between aromaticity and aliphaticity and between rigidity and flexibility of the copolyimides, the molar ratio of the dianhydrides was varied. Polyimide properties such as viscosity, solubility, optical transparency, color, dielectric constants, film flexibility and thermal stability are influenced by aromaticity/aliphaticity and/or flexibility/rigidity of the monomers. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
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27. Degradation Mechanism of Phenethylamine‐Based Interlayers in Perovskite Solar Cells and Breakthrough.
- Author
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Lee, Seri, Kim, Gyu Min, Miyasaka, Tsutomu, and Oh, Se Young
- Published
- 2023
- Full Text
- View/download PDF
28. Association between phthalate exposure and lower handgrip strength in an elderly population: a repeated-measures study.
- Author
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Kyoung-Nam Kim, Mee-Ri Lee, Yoon-Hyeong Choi, Hyojung Hwang, Se-Young Oh, ChoongHee Park, Yun-Chul Hong, Kim, Kyoung-Nam, Lee, Mee-Ri, Choi, Yoon-Hyeong, Hwang, Hyojung, Oh, Se-Young, Park, ChoongHee, and Hong, Yun-Chul
- Subjects
PHTHALATE esters ,POPULATION aging ,BODY mass index ,C-reactive protein ,DETECTION limit ,MEDICAL care ,DIET ,GRIP strength ,POLLUTANTS ,ENVIRONMENTAL exposure ,CARBOCYCLIC acids - Abstract
Background: Decreased muscle strength can lead to adverse health outcomes in the elderly. A potential association between phthalate exposure and muscle strength was suggested previously, but has not been investigated directly. We hypothesized that phthalate exposure is associated with lower handgrip strength and that the association is modified by the dietary omega-6 to omega-3 ratio.Methods: We analyzed 1,228 participants (≥60 years of age) recruited in Seoul and Asan, Republic of Korea. The study participants were surveyed up to three times between 2012 and 2015. At every survey, we collected urine samples and measured handgrip strength twice for each hand. The associations between urine phthalate metabolite concentrations and handgrip strength were evaluated using linear mixed models. Based on dietary information from 391 individuals who participated in the first survey in Seoul, we evaluated the heterogeneity of the association for those with high and low omega-6 to omega-3 ratios, using 8.81 (the 75th quantile) as a cutoff value.Results: Log-transformed creatinine-adjusted concentrations of mono-(2-ethyl-5-oxohexyl phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) were inversely associated with all measured handgrip strengths (β = -0.69 to -0.42, all p-values < 0.05). Associations between phthalate biomarkers and handgrip strength did not differ by sex. When the dietary subgroup was stratified by the omega-6 to omega-3 ratio, the associations were stronger among participants with high ratios.Conclusions: We found inverse associations between phthalate biomarkers and handgrip strength in the elderly; this association was modified by the dietary omega-6 to omega-3 ratio. [ABSTRACT FROM AUTHOR]- Published
- 2016
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29. Estimation of Total and Inorganic Arsenic Intake from the Diet in Korean Adults.
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Seo, Mi-Na, Lee, Seul-Gi, Eom, Sang-Yong, Kim, Jeongseon, Oh, Se-Young, Kwon, Ho-Jang, Kim, Heon, Choi, Byung-Sun, Yu, Il-Je, and Park, Jung-Duck
- Subjects
ARSENIC ,DIET ,HEALTH ,NONMETALS ,FOOD habits - Abstract
Arsenic (As) is a major environmental pollutant and a known human carcinogen that is widely distributed in the air, soil, and water. General population is mainly exposed to As through drinking water and food from the contaminated water and soil. Arsenic in drinking water is generally well controlled now. This study was performed to estimate total and inorganic As intake and to determine the major contributing source in the Korean adult diet. The study subjects were 2117 healthy adults (922 males and 1195 females) who had not been occupationally exposed to As. Total dietary intake was studied using the 24-h recall method, which included 138 specific food items. The estimates of total As and inorganic As intake were based on total and inorganic As contents in each food item consumed during the last 24 h. Daily dietary intake was estimated to be 1373.6 g. Total As intake was estimated to be 145.4 µg As/day. Total dietary As intake was correlated with consumption of fish/shellfish, seaweeds, and grains. Approximately 87 % of total dietary As intake was attributed to seafood, such as 105.5 µg As/day from fish/shellfish and 20.5 µg As/day from seaweeds. Inorganic As intake was estimated to be 10.4 µg As per day. Inorganic As intake was mainly provided by grains (6.4 µg As/day), followed by seaweeds and fish/shellfish. Our results indicate that seafood and grains are the main As dietary sources in Korean adults and that dietary As exposure may be associated with individual dietary habits and environmental As contamination among countries. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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- View/download PDF
30. Ceiling vision-based active SLAM framework for dynamic and wide-open environments.
- Author
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An, Su-Yong, Lee, Lae-Kyoung, and Oh, Se-Young
- Subjects
COMPUTER vision ,OPEN spaces ,SLAM (Robotics) ,FEATURE extraction ,MOBILE robots - Abstract
A typical indoor environment can be divided into three categories; office (or room), hallway, and wide-open space such as lobby and hall. There have been numerous approaches for solving simultaneous localization and mapping (SLAM) problem in office (or room) and hallway. However, direct application of the existing approaches to wide-open space may be failed, because it has some distinguished features compared to other indoor places. To solve this problem, this paper proposes a new ceiling vision-based active SLAM framework, with an emphasis on practical deployment of service robot for commercial use in dynamically changing and wide-open environments by adopting the ceiling vision. First, for defining ceiling feature which can be extracted regardless of complexity of ceiling pattern we introduce a model-free landmark, i.e., visual node descriptor, which consists of edge points and their orientations in image space. Second, a recursive 'explore and exploit' is proposed for autonomous mapping. It is recursively performed by spreading out mapped area gradually while the robot is actively localized in the map. It can improve map accuracy due to frequent small loop closing. Third, a dynamic edge link (DEL) is proposed to cope with environmental changes in the map. Owing to DEL, we do not need to filter out corrupted sensor data and to distinguish moving object from static one. Also, a self-repairing map mechanism is introduced to deal with unexpected installation or removal of inner structures. We therefore achieve long-term navigation. Several simulations and real experiments in various places show that the proposed active SLAM framework could build a topologically consistent map, and demonstrated that it can be applied well to real environments such as wide-open space in a city hall and railway station. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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31. ARgo.
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Park, Byung-Hwa and Oh, Se-Young
- Published
- 2014
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32. In vitro exposure of Penicillium mycotoxins with or without a modified yeast cell wall extract (mYCW) on bovine macrophages (BoMacs).
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Oh, Se-Young, Quinton, V., Boermans, Herman, Swamy, H., and Karrow, Niel
- Abstract
Penicillium mycotoxins (PMs) are contaminants that are frequently found in grain or crop-based silage for animal feed. Previously, we have characterized the potential immunotoxicity of the following PMs: citrinin (CIT), ochratoxin A (OTA), patulin (PAT), mycophenolic acid (MPA), and penicillic acid (PA) by using a bovine macrophage cell line (BoMacs). In the present study, cell proliferation was used as a bioassay endpoint to evaluate the efficacy of a modified yeast cell wall extract (mYCW), for preventing PM toxicity under various in vitro conditions such as the following: pH (3, 5, 7), incubation time (1, 2, 4, 6 h), percentage of mYCW (0.05, 0.1, 0.2, 0.5, 1.0 %), and PM concentration. mYCW was most effective in preventing the toxicity of 12.88 and 25.8 μM OTA at pH 3.0 ( p < 0.0001), regardless of incubation time ( p < 0.0001) and the percentage of mYCW ( p < 0.0001). An incubation time of 6 h ( p < 0.05) or 0.5 and 1.0 % mYCW ( p < 0.0001) significantly improved the efficacy of mYCW for preventing CIT toxicity. In contrast, 0.5 and 1.0 % of mYCW appeared to exacerbate the PAT toxicity ( p < 0. 0001). This effect on PAT toxicity was constantly observed with higher PAT concentrations, and it reached significance at a concentration of 0.70 μM ( p < 0.0001). mYCW had no effect on PA toxicity. These results suggest that mYCW may reduce OTA toxicity and, to some extent, CIT toxicity at pH 3.0. Although PAT toxicity was increased by mYCW treatment, PAT is readily degraded during heat treatment and may therefore be dealt with using other preventative measures. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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- View/download PDF
33. Modification of additive effect between vitamins and ETS on childhood asthma risk according to GSTP1 polymorphism: a cross -sectional study.
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So-Yeon Lee, Bong-Seong Kim, Sung-Ok Kwon, Se-Young Oh, Hye Lim Shin, Young-Ho Jung, Eun Lee, Song-I Yang, Hyung Young Kim, Ju-Hee Seo, Hyo-Bin Kim, Ji-Won Kwon, Hae-Ran Lee, Soo-Jong Hong, Lee, So-Yeon, Kim, Bong-Seong, Kwon, Sung-Ok, Oh, Se-Young, Shin, Hye Lim, and Jung, Young-Ho
- Subjects
ASTHMA ,DIET ,DISEASE susceptibility ,GENETIC polymorphisms ,PASSIVE smoking ,QUESTIONNAIRES ,TRANSFERASES ,VITAMIN A ,VITAMIN C ,VITAMIN E ,VITAMINS ,PHENOTYPES ,CROSS-sectional method ,BETA carotene ,ODDS ratio - Abstract
Background: Asthma is characterized by airway inflammation, and bronchial airways are particularly susceptible to oxidant-induced tissue damage.Objective: To investigate the effect of dietary antioxidant intake and environmental tobacco smoke (ETS) on the risk of childhood asthma according to genotypes susceptible to airway diseases.Methods: This cross-sectional study included 1124 elementary school children aged 7-12 years old. Asthma symptoms and smoking history were measured using the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Intake of vitamin A (including retinol and β-carotene), C, and E was measured by a semi-quantitative food frequency questionnaire (FFQ). GSTP1 polymorphisms were genotyped from peripheral blood samples.Results: ETS was significantly associated with presence of asthma symptoms (adjusted odds ratio [aOR], 2.48; 95 % confidence interval [CI], 1.29-4.76) and diagnosis (aOR, 1.91; 95 % CI, 1.19-3.06). Dietary antioxidant intake was not associated with asthma symptoms, although ETS plus low vitamin A intake showed a significant positive association with asthma diagnosis (aOR, 2.23; 95 % CI, 1.10-4.54). Children with AA at nucleotide 1695 in GSTP1 who had been exposed to ETS and a low vitamin A intake have an increased risk of asthma diagnosis (aOR, 4.44; 95 % CI,1.58-12.52) compared with children who had not been exposed to the two risk factors. However, ETS exposure and low vitamin A intake did not significantly increase odds of asthma diagnosis in children with AG or GG genotypes.Conclusion: Low vitamin A intake and ETS exposure may increase oxidative stress and thereby risk for childhood asthma. These relationships may be modified by gene susceptibility alleles of GSTP1. [ABSTRACT FROM AUTHOR]- Published
- 2015
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34. Line segment-based fast 3D plane extraction using nodding 2D laser rangefinder.
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An, Su-Yong, Lee, Lae-Kyoung, and Oh, Se-Young
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ELECTRONIC data processing ,DATA extraction ,TWO-dimensional models ,RANGEFINDERS (Engineering) ,ROBOTICS - Abstract
Three-dimensional (3D) data processing has applications in solving complex tasks such as object recognition, environment modeling, and robotic mapping and localization. Because using raw 3D data without preprocessing is very time-consuming, extraction of geometric features that describe the environment concisely is essential. In this sense, a plane can be a suitable geometric feature due to its simplicity of extraction and the abundance in indoor environments. This paper presents an online incremental plane extraction method using line segments for indoor environments. Our data collection system is based on a “nodding” laser scanner, so we exploit the incremental nature of its data acquisition in which physical rotation and 3D data processing are conducted in parallel. Line segments defined by two end points become supporting elements that comprise a plane, so a large proportion of scan points can be ignored once the line segments are extracted from each scan slice. This elimination of points reduces the algorithm complexity and computation time. Experiments with the tens of complete scan data sets which were acquired from a typical indoor environment demonstrated that our method was at least three times faster than the state-of-the-art methods. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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- View/download PDF
35. Improving the performance of organic solar cells using an electron transport layer of B4PyMPM self-assembled nanostructures.
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Ji, Chan-Hyuk, Oh, Il-Soo, and Oh, Se-Young
- Abstract
The electron transport (ETL) layer improves power conversion efficiency (PCE) in organic photovoltaic cells (OPVs) through the incorporation of the cathode interfacial layers. Here, we introduce [bis-4,6-(3,5-di-4-pyridylphenyl)-2-methylpyrimidine] (B4PyMPM) as an n-type buffer layer consisting of a self-organized layer with a horizontal configuration in bulk heterojunction OPVs. It is demonstrated that self-organization of this B4PyMPM compound in which molecules adopt a horizontal orientation parallel to the organic semiconducting substrate induces a large local interfacial electric field that results in a significant enhancement of exciton dissociation. The device using B4PyMPM as an ETL layers has a significantly high open circuit voltage ( V = 0.64 V), good short circuit current ( J = 8.24 mA/cm), good fill factor ( FF = 0.65) and good PCE (3.42%). The physical properties of the device have also been studied from the measurements of impedance spectroscopy and photocurrent, which directly show the mechanisms occurring inside OPVs. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]
- Published
- 2015
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- View/download PDF
36. Maternal Blood Manganese and Early Neurodevelopment: The Mothers and Children's Environmental Health (MOCEH) Study.
- Author
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Chung, Soo Eun, Cheong, Hae-Kwan, Ha, Eun-Hee, Kim, Boong-Nyun, Ha, Mina, Kim, Yangho, Hong, Yun-Chul, Park, Hyesook, and Oh, Se-Young
- Subjects
INFANT development ,MANGANESE ,INGESTION ,NERVOUS system ,QUESTIONNAIRES ,REGRESSION analysis ,RESEARCH funding ,VIDEO recording ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
BACKGROUND: Manganese is an essential trace element and common component of water, soil, and air. Prenatal manganese exposure may affect fetal and infantile neurodevelopment, but reports on in utero manganese exposure and infant neurodevelopment are rare. OBJECTIVE: This study was conducted to investigate a relationship between maternal blood manganese level and neurodevelopment of infants at 6 months of age. METHODS: Data were obtained from the Mothers and Children's Environmental Health (MOCEH) birth cohort study. The study population included 232 pairs of pregnant women and their infants at 6 months of age. Maternal blood manganese was measured at term, just before delivery. Mental and psychomotor development in infancy was assessed at 6 months of age using the Bayley Scales of Infant Development. The relationship between maternal blood manganese level and the mental and psychomotor development indexes (MDI and PDI) was estimated for manganese modeled as a linear and as a categorical variable and using penalized splines for nonlinear modeling. RESULTS: Mean ± SD maternal blood manganese concentration was 22.5 ± 6.5 µg/L. After adjustment for potential confounders, blood manganese was used as a continuous variable in a linear and nonlinear model. Associations between maternal blood manganese and MDI and PDI scores followed an inverted U-shape dose--response curve after adjustment for potential confounders, with lower scores associated with both low and high blood concentrations [MDI: likelihood-ratio test (LRT)p = 0.075, PDI: LRTp = 0.038]. Associations of both outcomes with increasing blood manganese shifted from positive to negative at concentrations of 24--28 µg/L in this cohort of term, normal birth weight children. CONCLUSION: Although no cut-off point has been established to define manganese toxicity, both high and low blood manganese levels may be associated with neurobehavioral function in infants. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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37. Analysis of hybrid membrane and chemical absorption systems for CO capture.
- Author
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Binns, Michael, Oh, Se-Young, Kwak, Dong-Hun, and Kim, Jin-Kuk
- Abstract
Amine-based absorption of CO is currently the industry standard technology for capturing CO emitted from power plants, refineries and other large chemical plants. However, more recently there have been a number of competing technologies under consideration, including the use of membranes for CO separation and purification. We constructed and analyzed two different hybrid configurations combining and connecting chemical absorption with membrane separation. For a particular flue gas which is currently treated with amine-based chemical absorption at a pilot plant we considered and tested how membranes could be integrated to improve the performance of the CO capture. In particular we looked at the CO removal efficiency and the energy requirements. Sensitivity analysis was performed varying the size of the membranes and the solvent flow rate. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
38. Ceiling vision-based topological mapping and exploration in wide-open area.
- Author
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An, Su-Yong, Lee, Lae-Kyoung, and Oh, Se-Young
- Published
- 2013
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39. Fast incremental 3D plane extraction from a collection of 2D line segments for 3D mapping.
- Author
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An, Su-Yong, Lee, Lae-Kyoung, and Oh, Se-Young
- Abstract
Three-dimensional (3D) data processing has recently acquired greater importance in solving complex tasks such as object recognition, environment modeling, and robotic mapping and localization. Since using raw 3D data without preprocessing is very time-consuming, extraction of geometric features that describe the environment concisely is essential. A plane is a suitable geometric feature due to its richness and simplicity of extraction. This paper presents an online incremental plane extraction method using line segments. Since our system is based on a nodding laser scanner, we exploit the incremental nature of data acquisition in which physical rotation and algorithm implementation are conducted in parallel. In contrast to other plane extraction methods, line segments defined by two end points become supporting elements that comprise a plane, so we need not handle all the scan points once the line segments are extracted from each scan slice. This reduces the algorithms complexity and the computation time. Experimental validation and comparison with state of the art method were conducted using tens of complete scan data sets acquired from a typical indoor environment. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
40. Indoor mapping using planes extracted from noisy RGB-D sensors.
- Author
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Lee, Tae-kyeong, Lim, Seungwook, Lee, Seongsoo, An, Shounan, and Oh, Se-young
- Abstract
This paper presents a fast and robust plane feature extraction and matching technique for RGB-D type sensors. We propose three algorithm components required to utilize the plane features in an online Simultaneous Localization and Mapping (SLAM) problem: fast plane extraction, frame-to-frame constraint estimation, and plane merging. For the fast plane extraction, we estimate local surface normals and curvatures by a simple spherical model and then segment points using a modified flood fill algorithm. In plane parameter estimation, we suggest a new uncertainty estimation method which is robust against the measurement bias, and also introduce a fast boundary modeling method. We associate the plane features based on both the parameters and the spatial coverage, and estimate the stable constraints by the cost function with a regulation term. Also, our plane merging technique provides a way of generating local maps that are useful for estimating loop closure constraints. We have performed real-world experiments at our lab environment. The results demonstrate the efficiency and robustness of the proposed algorithm. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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41. Fast Nearest Neighbor Search using Approximate Cached k-d tree.
- Author
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Choi, Won-Seok and Oh, Se-Young
- Abstract
We introduce a fast Nearest Neighbor Search (NNS) algorithm using an Approximate Cached k-d tree (ACk-d tree) structure for low dimensional data sets. The search process of the standard k-d tree starts from the root node and employs a tentative back-tracking search. In contrast, the proposed method begins to search at the appropriate leaf node (cached node) and applies a depth-first nontentative search. This method improves searching speed, with tradeoff of the searching accuracy. To get a proper starting node, the proposed method is based on two properties: i) The ith query point is likely to be close to the (i−1)th query point, ii) The ith query point is likely to be close to the ith model point. These properties are rather right, in case of practical 3D point sets which are consecutively acquired from 3D point sensors (e.g. a stereo camera, the Kinect sensor, and LIDAR). Results show that the search time of the proposed method is superior to other variants of k-d tree for practical point data sets. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
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42. Adaptive Sliding Window for hierarchical pose-graph-based SLAM.
- Author
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Lim, Seungwook, Lee, Tae-kyeong, Lee, Seongsoo, An, Shounan, and Oh, Se-young
- Abstract
We propose the Adaptive Sliding Window (ASW) which is a novel approach to solve the hierarchical pose-graph-based (PGB) simultaneous localization and mapping (SLAM) problem. We adjust the size of the sliding window (SW) for incremental optimization by eliminating the portion of the graph which has a low degree of similarity to the rest of the graph and by dropping poses which are not related to the latest robot pose. The decision is made by utilizing a graph-cut algorithm, where the weight matrix is created from the constraints' information matrices estimated by the front-end system. Our method provides the optimal window size to minimize information loss and linearization error. Moreover, due to the optimal SW size, our method produces the additional advantage of constructing an efficient hierarchical structure. To make a high-level graph, we create a high-level node (local map) by immobilizing the truncated part from the SW. The local maps can be efficiently matched in the front-end system to estimate the constraints between the high-level nodes. Therefore, our approach increases localization accuracy. We tested our algorithm on the indoor dataset obtained in an apartment environment to demonstrate the effectiveness of the proposed method. When our approach was applied to the hierarchical PGB SLAM back-end, we efficiently improved both localization accuracy (by reducing the information loss) and computational efficiency simultaneously. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
43. Fast Iterative Closest Point framework for 3D LIDAR data in intelligent vehicle.
- Author
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Choi, Won-Seok, Kim, Yang-Shin, Oh, Se-Young, and Lee, Jeihun
- Abstract
The Iterative Closest Point (ICP) algorithm is one of the most popular methods for geometric alignment of 3-dimensional data points. We focus on how to make it faster for 3D range scanner in intelligent vehicle. The ICP algorithm mainly consists of two parts: nearest neighbor search and estimation of transformation between two data sets. The former is the most time consuming process. Many variants of the k-d trees have been introduced to accelerate the search. This paper presents a remarkably efficient search procedure, exploiting two concepts of approximate nearest neighbor and local search. Consequently, the proposed algorithm is about 24 times faster than the standard k-d tree. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
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44. A hierarchical RBPF SLAM for mobile robot coverage in indoor environments.
- Author
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Lee, Tae-kyeong, Lee, Seongsoo, and Oh, Se-young
- Published
- 2011
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45. Novel OPC method to create sub 45nm contact hole using design based metrology.
- Author
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Lee, Dong-Jin, Oh, Se-young, Park, Jong-cheon, Choi, Jin-young, Kim, Jungchan, Kim, Cheolkyun, and Yim, Donggyu
- Published
- 2009
- Full Text
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46. DFM application on dual tone sub 50nm device.
- Author
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Nam, Byoung-Sub, Moon, James, Jung, Joo-Hong, Kong, Dong-Ho, Oh, Se-young, Kim, Cheol-Kyun, Nam, Byung-Ho, and Yim, Dong Gyu
- Published
- 2008
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47. Global Localization for the Mobile Robot Based on Natural Number Recognition in Corridor Environment.
- Author
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An, Su-Yong, Kang, Jeong-Gwan, Oh, Se-Young, and Baek, Doo San
- Abstract
This paper proposes global localization for mobile robot by introducing local goal based navigation and model-based object recognition. In navigation stage, the robot follows the wall while detecting a door using a laser scanner, and then sets up the local goal near detected door. In recognition stage, room number is recognized and also ambiguous room number is rejected by multistage rejection method (MRSM) in order to reduce false recognition. Recognition results by various methods are demonstrated and room number feature map is built after exploring the whole corridor of LG research center. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
48. Comparative study of chromeless and attenuated phase shift mask for 0.3-k1 ArF lithography of DRAM.
- Author
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Eom, Tae-Seung, Lim, Chang M., Kim, Seo-Min, Kim, Hee-Bom, Oh, Se-Young, Ma, Won-Kwang, Moon, Seung-Chan, and Shin, Ki S.
- Published
- 2003
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49. Double-exposure strategy using OPC and simulation and the performance on wafer with sub-0.10-m design rule in ArF lithography.
- Author
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Oh, Se-Young, Kim, Wan-Ho, Yune, Hyoung-Soon, Kim, Hee-Bom, Kim, Seo-Min, Ahn, Chang-Nam, and Shin, Ki-Soo
- Published
- 2002
- Full Text
- View/download PDF
50. Dietary patterns and weight status associated with behavioural problems in young children.
- Author
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Oh, Se-Young, Ahn, Hyojin, Chang, Namsoo, Kang, Myung-Hee, and V Oh, Jiyoung
- Subjects
BEHAVIOR disorders in children ,FOOD habits ,BODY weight ,SOCIAL skills ,CHILD nutrition ,PRESCHOOL children ,PUBLIC health ,HEALTH - Abstract
ObjectiveTo investigate the associations of behavioural problems with dietary patterns and weight status in young children.DesignWe assessed poor social skills and behavioural problems with a seventy-six-item Preschool and Kindergarten Behavior Scale (PKBS) and found three dietary patterns (‘Korean healthy’, ‘animal foods’ and ‘sweets’) in food/food group intake data assessed by an FFQ and analysed using factor analysis. Multiple logistic regression analyses were used to assess the association of diet and weight status with behaviour.SettingPre-schools in the metropolitan areas of Korea.SubjectsA total of 1458 children (mean age 5·2 (sd 0·9) years) from the Practical Approach for Better Maternal and Child Nutrition and Health Study conducted from 2001 to 2005.ResultsThe ‘Korean healthy’ pattern showed a significant inverse association with poor social skills in the second highest quartile group (OR = 0·42; 95 % CI 0·21, 0·82) compared with the lowest quartile group for boys. For girls, the ‘sweets’ pattern was associated with a greater risk of poor social skills (OR = 3·41; 95 % CI 1·29, 9·01 at Q4 v. Q1) and problem behaviours (OR = 2·80; 95 % CI 1·05, 7·43 at Q4 v. Q1). Regarding weight status, both underweight and overweight boys had a higher risk of poor social skills than normal-weight boys.ConclusionsDietary patterns and weight status are important indicators for the behaviour of young children. Healthy and unhealthy dietary patterns, underweight and overweight status, and gender differences should thus be considered for further studies. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
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