• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.46.3-46.3
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• 2019

We present our observational and theoretical investigation of Raman-scattered features in symbiotic stars (SySts). SySts are long interacting binaries, consisting of a hot compact star and an evolved giant, whose interaction via accretion process is at the origin of a tangled network of gas and dust nebulae. These systems are ideal objects to study a variety of important astrophysical problems, and have also been proposed as possible progenitors of type Ia supernova. In this talk, we emphasize that Raman-scattered features are exclusive spectroscopic tools to probe the stellar wind accretion processes in SySts. We studied mass transfer and mass loss processes in SySts using high resolution spectra obtained with 1.8m telescope at Mt. Bohyun and the 6.5m Magellan-Clay telescope combining with the theoretical modeling of radiative transfer of Raman-scattered features. We also note that there are a much smaller number of SySts known in our Galaxy, implying the necessity of systematic search programs. In view of the fact that Raman O VI features at $6830{\AA}$ are found in only bona fide SySts, we will carry out a photometric search of objects with Raman O VI features using a narrow band filter centered at $6830{\AA}$ in Local group galaxies.

• 중국학논총
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• no.66
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• pp.105-126
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• 2020

Complement is a special grammatical phenomenon in Chinese. There is no complement in Korean, so complement teaching is a difficulty. There are some similarities between the degree complement with "de" and the modality complement. For a long time, there has been a phenomenon of fuzzy classification in the academic circle, which also affects the teaching of Chinese as a foreign language. There are several different views on these two kinds of complements in the current textbooks. This makes students and teachers feel very confused. From the perspective of Chinese teaching, the author analyzes the characteristics, classification and grammatical significance of these two kinds of complements, and investigates the four sets of current teaching materials. It is found that: some teaching materials are confused in terms of terms and classification; some teaching materials are not fully reproduced in terms of knowledge points; the students are prone to have partial errors, and the situation of the clutch words with modal complements is ignored by most teaching materials. Some textbooks overemphasize Verb Copying in the arrangement of modal complements. Most textbooks are lack of context. The author puts forward some teaching suggestions. In class, teachers should concentrate on speaking and practicing, and focus on the types of errors that students are prone to make. The textbooks should be arranged according to the outline, the two kinds of "similar" complements should be clearly classified, the context should be added appropriately, and the textbooks compiled in South Korea can be nationalized. Students should listen carefully, participate in classroom activities and interact with teachers. Ask for advice in case of any problem you don't understand..

• Journal of Species Research
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• v.12 no.1
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• pp.55-67
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• 2023

Two new records of marine nematodes, belonging to the family Ironidae de Man, 1876, are reported based on the specimens collected from intertidal sediments from the west coast of Korea. Conilia sinensis is characterized by a relatively long body length, a well-developed buccal cavity with three claw-like teeth, the presence of a single spicule with transverse striations, the presence of rib-shaped telamons, and single precloacal supplement. Pheronous donghaiensis is distinguished from other species of the genus by a well-developed buccal cavity with four claw-like solid teeth and minute denticles, relatively short and thick spicules with the central septum, the presence of 8-9 curved tubular-shaped precloacal supplements, and a sharp pointed tail with three small tubular supplements arranged into two rows in males. In this report, we provide a taxonomic description and illustrations of two unrecorded species of the family Ironidae by differential interference contrast microscopy. This is the first taxonomic report on the species of the family Ironidae from Korea.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.72.1-72.1
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• 2021

Galaxy mergers are known to have been one of the main drivers in galaxy evolution in a wide range of environments. However, in galaxy clusters, high-speed encounters have been believed to undermine the role of mergers as a driver in galaxy evolution. Nonetheless, a high fraction (~38% in Sheen et al. 2012 and ~20% in Oh et al. 2018) of galaxies with post-merging features have been reported in deep (>~28 mag/arcsec2) optical surveys of cluster galaxies. The authors argue that these galaxies could have merged outside of the cluster and, later, fallen into the cluster, sustaining their long-lasting post-merging features. On the other hand, when galaxy clusters interact, galaxy orbits might be destabilized resulting in a higher galaxy merger rate. To test this idea, we measure the ongoing-merger fraction of galaxies in deep DECam mosaic data of seven Abell clusters (A754, A2399, A2670, A3558, A3574, A3659 and A3716) with a variety of dynamical states (0.016

• Journal of Platform Technology
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• v.12 no.2
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• pp.58-63
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• 2024

CNNs tend to take a long time to learn and consume a lot of power due to lack of system resources with many data processing units when there are repetitive handles that do not have high performance in the image field. In this paper, we propose a handling method based on a low-power bus that can increase the exchange rate of multipliers and multiplicands within the convolution mixer, which is a tendency activity that occurs when a convolution mixer has multiplication, which is the core element of combination. Convolutional neural networks have proprietary low-power shared processor support and the design was implemented on an Intel DE1-SoC FPGA board using Verilog-HDL. The experiments validated the performance by comparing it with the exchange rate of the multiplier originally proposed by Shen on MNIST's numeric image database.

• Asian Journal of Atmospheric Environment
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• v.12 no.2
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• pp.165-177
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• 2018

Particulate matter (PM) measurements are important in air quality, public health, epidemiological studies and decision making for short and long-term policies implementation. However, only few cities in the word have advance air quality-monitoring networks able to provide reliable information of PM leaves in the ambient air, trends and extent of the pollution. In Colombia, only major cities measure PM concentrations. Available measurements from Bogota, Medellin and Bucaramanga show that PM concentration are well above World Health Organization guidelines, but up to now levels and trends of PM in other cities and regions of the country are not well known. Satellite measurements serve as an alternative approach to study air quality in regions were surface measurements are not available. The aim of this study is to perform a spatial and temporal assessment of PM in the ambient air of Colombia. We used Aerosol optical depth (AOD) retrieved by the Moderate Resolution Imaging Spectroradiometer (MODIS) satellite of NASA and surface measurements from the air quality networks of Bogota, Medellin and Bucaramanga. In a first step, we estimated the correlation between MODIS-AOD and monthly average surface measurements (2000 to 2015) from these three cities, obtaining correlation coefficient R values over 0.4 for the cities under study. After, we used AOD and $PM_{10}$ measurements to study the temporal evolution of PM in different cities and regions. Finally, we used AOD measurements to identify cities and regions with the highest AOD levels in Colombia. All the methods presented in this paper may serve as an example for other countries or regions to identify and prioritize locations that require the implementation of more accurate air quality measurements.

• Membrane and Water Treatment
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• v.3 no.3
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• pp.169-179
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• 2012

One of the major limitations in the use of commercial aromatic polyamide thin film composite (TFC) reverse osmosis (RO) membranes is to maintain high performance over a long period of operation, due to the sensitivity of polyamide (PA) skin layer to oxidizing agents, such as chlorine, even at very low concentrations in feed water. This article reports surface modification of a commercial TFC RO membrane (BW30-Dow Filmtec) by covering it with a thin film of poly(vinyl alcohol) (PVA) crosslinked with glutaraldehyde (GA) to improve its resistance to chlorine. Crosslinking reaction was carried out at 25 and $40^{\circ}C$ by using PVA 1.0 wt.% solutions at different GA/PVA mass ratio, namely 0.0022, 0.0043 and 0.013. Water swelling measurements indicated a maximum crosslinking density for PVA films prepared at $40^{\circ}C$ and GA/PVA 0.0043. ATR-FTIR and TGA analysis confirmed the reaction between GA and PVA. SEM images of the original and modified membranes were used to evaluate the surface coating. Chlorine resistance of original and modified membranes was evaluated by exposing it to an oxidant solution (NaClO 300 mg/L, NaCl 2,000 mg/L, pH 9.5) and measuring water permeability and salt rejection during more than 100 h period. The surface modification effectively was demonstrated by increasing the chlorine resistance of PA commercial membrane from 1,000 ppm.h to more than 15.000 ppm.h.

• Journal of Microbiology and Biotechnology
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• v.27 no.11
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• pp.1925-1931
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• 2017

Korean red pine (Pinus densiflora) bark extract, PineXol (PX), was investigated for its potential antioxidant and anti-inflammation effects in vitro. It was hypothesized that PX treatment ($25-150{\mu}g/ml$) would reduce the lipid synthesis in HepG2 hepatocytes as well as lipid accumulation in 3T3-L1 adipocytes. Hepatocytes' intracellular triglycerides and cholesterol were decreased in the PX $150{\mu}g/ml$ treatment group compared with the control (p < 0.05). Consequently, de novo lipogenic proteins (acetyl-CoA carboxylase 1, stearoyl-CoA desaturase 1, elongase of very long chain fatty acids 6, glycerol-3-phosphate acyltransferase 1, and sterol regulatory element-binding protein 1) were significantly decreased in hepatocytes by PX $150{\mu}g/ml$ treatment compared with the control (p < 0.05). In differentiated 3T3-L1 adipocytes, the lipid accumulation was significantly attenuated by all PX treatments (p < 0.01). Regulators of adipogenesis, including CCAAT-enhancer-binding proteins alpha, peroxisome proliferatoractivated receptor gamma, and perilipin, were decreased in PX $100{\mu}g/ml$ treatment compared with the control (p < 0.05). In conclusion, PX might have anti-obesity effects by blocking hepatic lipogenesis and by inhibiting adipogenesis in adipocytes.

• Clinical and Experimental Pediatrics
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• v.54 no.6
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• pp.267-271
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• 2011

Distal duplication, or trisomy 15q, is an extremely rare chromosomal disorder characterized by prenatal and postnatal overgrowth, mental retardation, and craniofacial malformations. Additional abnormalities typically include an unusually short neck, malformations of the fingers and toes, scoliosis and skeletal malformations, genital abnormalities, particularly in affected males, and, in some cases, cardiac defects. The range and severity of symptoms and physical findings may vary from case to case, depending upon the length and location of the duplicated portion of chromosome 15q. Most reported cases of duplication of the long arm of chromosome 15 frequently have more than one segmental imbalance resulting from unbalanced translocations involving chromosome 15 and deletions in another chromosome, as well as other structural chromosomal abnormalities. We report a female newborn with a de novo duplication, 15q24- q26.3, showing intrauterine overgrowth, a narrow asymmetric face with down-slanting palpebral fissures, a large, prominent nose, and micrognathia, arachnodactyly, camptodactyly, congenital heart disease, hydronephrosis, and hydroureter. Chromosomal analysis showed a 46,XX,inv(9)(p12q13),dup(15)(q24q26.3). Array comparative genomic hybridization analysis revealed a gain of 42 clones on 15q24-q26.3. This case represents the only reported patient with a de novo 15q24-q26.3 duplication that did not result from an unbalanced translocation and did not have a concomitant monosomic component in Korea.

• Korean Institute of Interior Design Journal
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• v.21 no.5
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• pp.3-11
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• 2012

The first visual contact in architecture happens in surface, and it could be significant object as well as the starting point to recognize the essence and perceive the buildings. Architecture surface could not get out of the restriction of structures and materials that support buildings for a long time in the past. Architecture surface in the past should fulfill the structural role to form are appearance of buildings and support buildings at the same time, so it was difficult to get out of logic for material and thickness of walls, arrangements and sizes of windows. However, since the modern age, architecture surface came to be freer according to the development of building technology, and development of technology changes shows tendencies to express role of new design factor as an architectural element emphasized expression and autonomy,s which was escaped from the subordinate relationship that the surface of building must do the structural function. In this study, it would be examined the expressive characteristics of various epidermis that are expressed in architecture of Herzog & de Meuron since the end of 20thcentury focused on comprehended and analyzed results of changes and characteristics of contemporary society. Through this, it would be comprehended the epidermis of architecture that has particular character expressed in modern buildings of Herzog & de Meuron, and it would be composed a certain linkage between this and characteristics of contemporary society and it would be investigated that the establishing process of inner spaces. Identification through case analysis for this would perform a role of catalyst for the new possibility and development of contemporary architecture's surface expression in the future.