• Bulletin of the Korean Chemical Society
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• v.23 no.1
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• pp.35-40
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• 2002

Photoreaction of guest organic anions in layered organic-inorganic hybrid materials was investigated. The layered hybrids were synthesized by an anion-exchange reaction of $[LiAl_2(OH)_6]Cl{\cdot}yH_2O$ layered double hydroxide with aqueous (Z,Z)- and (E,E)-muconates under inert atmospheric condition, to give new organicinorganic hybrids of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$ and $[LiAl_2(OH)_6]_2[(E,E)-C_6H_4O_4]{\cdot}H_2O$, respectively. The basal spacings calculated by XRPD of intercalates indicate that muconate anions have almost vertical arrangements against the host $[LiAl_2(OH)_6]^+$ lattices in the interlayer of organic-inorganic hybrid materials. When UV light was irradiated on the suspension of $[LiAl_2(OH)_6]_2[(Z,Z)-C_6H_4O_4]{\cdot}zH_2O$, the (Z,Z)-muconate anions of the gallery space of hybrids were polymerized in the aqueous media while it was isomerized into more stable (E,E)-muconate in the methanollic suspension in the presence of catalytic amount of molecular iodine. All the products were characterized using elemental analysis, TGA, XRPD, FT-IR, $^1H$ NMR and $^{13}C$ CP-MAS NMR.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.2
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• pp.41.1-41.1
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• 2016

The Galactic center, Sagittarius A* (Sgr A*), is the closest supermassive black hole and emits synchrotron radiation. It provides great opportunity to study the origin of mm/sub-mm emission. Currently, two competing models have been suggested as a jet base and a radiatively inecient accretion flow (RIAF). To unveil the properties, the extremely high resolution(${\sim}10{\mu}as$) corresponding to the projected Schwarzschild radius of ~0.1AU is necessary. With KVN, a jet model can be tested by multi- frequency simultaneous observations because the optically thick surface in a jet (i.e. radio core) moves toward the center at a higher frequency. We conducted 8 observations with KVN at 43/86GHz in 2015, and found that the measured positional shift to the reference calibrator, J1744-3116, was ~0.3 mas to the south of Sgr A* using the source frequency phase referencing (SFPR) at Q/W bands for the first time. With the result, in the future, we will attempt to measure the variation of source position shifts that can constrain the direction of approaching jets and the variability of black hole activity of Sgr A*.

• Molecules and Cells
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• v.26 no.6
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• pp.548-553
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• 2008

The erect habit of fruit setting is a unique characteristic of ornamental peppers and wild pepper species. The erect habit is known to be controlled by the up locus on pepper (Capsicum annuum L.) chromosome 12. The result of a genetic analysis using Saengryeog 211 (pendant), Saengryeog 213 (erect), and their $F_1$ and $BC_1$ progeny demonstrated that up is a recessive gene. To develop an up-linked marker, bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP) were employed using 108 $F_{2:3}$ individuals. The closest AFLP marker, $A2C7_{469}$, was located at a genetic distance of 1.7 cM from the up locus and was converted into a cleaved amplified polymorphic sequence (CAPS) marker. This marker was mapped at a genetic distance of 4.3 cM from the up locus. When the CAPS was applied to seven ornamental lines and 27 breeding lines with erect fruit, these genotypes of 28 lines were correctly predicted. Thus, the CAPS marker will be useful for marker-assisted selection (MAS) of pepper breeding lines with the up allele at the early seedling stage.

• Acta Via Serica
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• v.2 no.1
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• pp.85-108
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• 2017

This paper details the advance of the "Hui" (回) people to Korea and their socioeconomic activities in forming their own community during the late Goryeo and early Joseon period. Hui (回) or Hui Hui (回回) is generally recognized as representative of Muslim culture in Chinese and Korean sources. From the $8^{th}$ century, Korean-Muslim cultural relations accelerated as an outcome of ancient Chinese-West Asian commercial transactions along the Silk Road. These contacts between Muslims and Koreans on the Korean peninsula are borne out by references to Korea found in 23 Islamic sources written between the $9^{th}$ and $16^{th}$ centuries by 18 Muslim scholars, including Ibn Khurdadbih, Sulaiman al-Tajir, and Mas'ud1 i. Ibn Khurdadbih was the first Arab who wrote of Muslims' residence in the Unified Silla Kingdom (661-935CE). However, in the period of Silla, we could not find any reliable written documents in Korea to show encounters between Korea and the Muslim world. In the Goryeosa (GS) chronicle, Muslim merchants who came to Korea were described as "Daesik" (大食: Tashi). Daesik (Tashi) is most probably derived from "Tajir", which means "trader" in Muslim language. Muslims' mass influx and their wide ranging influence on Korean society manifested from the late $13^{th}$ century when the Goryeo Dynasty first came under Mongol control and afterward in the early $15^{th}$ century with the new dynasty of Joseon in Korea.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.121-123
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• 2015

We report our measurements of the trigonometric distance and proper motion of IRAS 20056+3350, obtained from the annual parallax of $H_2O$ masers. Our distance of $D=4.69^{+0.65}_{-0.51}kpc$, which is 2.8 times larger than the near kinematic distance adopted in the literature, places IRAS 20056+3350 at the leading tip of the Local arm and proximal to the Solar circle. We estimated the proper motion of IRAS 20056+3350 to be (${\mu}_{\alpha}cos{\delta}$, ${\mu}_{\delta}$) = ($-2.62{\pm}0.33$, $-5.65{\pm}0.52$) $mas\;yr^{-1}$ from the group motion of $H_2O$ masers, and use our results to estimate the angular velocity of Galactic rotation at the Galactocentric distance of the Sun, ${\Omega}_0=29.75{\pm}2.29km\;s^{-1}kpc^{-1}$, which is consistent with the values obtained for other tangent points and Solar circle objects.

• Journal of the Korean Chemical Society
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• v.42 no.3
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• pp.277-284
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• 1998

Dendritic macromolecules of the first to fourth generation were synthesized, using alkenylation and hydrosilation cycles with allylmagnesium bromide and dichloromethylsilane as building blocks and siloxane tetramer $(Me(CH_2=CH)SiO)_4$, as core molecule. By the reaction of the dichloromethylsilyl-capped generation (G4P) with p-bromophenol, p-phenylphenol and lithium phenyethynylide, dendrimers with specific functions (G4P-BP (Mw: 16,300), G4P-PP (16,121), and CAP-PA (11,764)) have been produced. Analysis of new dendrimers by NMR, UV and MALD1 mass spectrometry suggests that they are pure and unified.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3805-3810
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• 2013

The surface modification of silica particles (SPs) was systemically conducted by the treatment of 0.1-10 wt % phenylsilanetriol (PST) on the basis of SPs used through two step processes: 1) the PST coating of SPs via evaporation under reduced pressure and 2) their thermal condensation leading to Si-O-Si bond formation via heating at $130^{\circ}C$. The evaluation of the modified SPs was conducted by the simple floating test on water and the measurement of the contact angle (CA) of water droplet on the 2-dimensional layer of modified SPs on slide glass. When PST was used about 2 wt % or above on the basis of SPs (about average size: 50 nm) used, the modified SPs were fully floated on the water and all dispersed into upper organic solvent layer after a shaking with the mixture of the water and benzene, indicating that the modified SPs have hydrophobic properties. The modified SPs were characterized by $^{29}Si$ MAS NMR and physicochemical properties including SEM, TEM, BET, adsorption/desorption isotherms, etc. were measured and compared each other in details. This research demonstrates that the organosilanetriol is a good modifier applicable for the surface modification of inorganic oxide particles using a low amount of modifier on the basis of oxide particles used.

• The Journal of Information Systems
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• v.19 no.1
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• pp.79-96
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• 2010

The organizations in the competitive business environment are under pressure of handling internal management processes as well as external supply chain issues. In addition, the paradigm of supply chain management (SCM) has been shifted from static to dynamic problems. For the efficient SCM, organizations should be a RTE (Real Time Enterprises) that views entire supply chains as a single entity. In this paper, the agent system that makes RTE and dynamic supply chains possible is developed. Then, the developed agent system is verified in the TAC SCM(Trading Agent Competition Supply Chain Management) experimental environment and a dashboard is also developed for monitoring management activities of supply chains. The contributions of this paper are as followings. First, unlike the previous agent systems, the suggested agent system in this paper provides autonomy and scalability using SOA. Second, this suggested model for dynamic environment can be applied for the development of software supporting a SCM.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.233-237
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• 2015

Background: Lung cancer is the leading cause of cancer death in Brunei Darussalam, accounting for almost 20% of the total. The epidermal growth factor receptor (EGFR) is a member of the erbB family of tyrosine kinase receptor proteins, which includes c-erbb2(HER2/neu), erb-B3, and erb-B4. EGFR overexpression is found in a third of all epithelial cancers, often associated with a poor prognosis. Materials and Methods: Protein expression of EGFR in 27 cases of lung cancer tissue samples and 9 cases of normal lung tissue samples was evaluated using an immunohistochemical approach. Results: The results demonstrated significant increase and overexpression of EGFR in Bruneian lung cancer tissue samples in comparison to normal lung tissue. However, there was no significant relationship between clinicopathologic variables (age and sex) of patients and EGFR protein expression. Conclusions: EGFR is overexpressed in Bruneian lung cancer patient tissue samples in comparison to normal lung tissue samples. This may indicate that EGFR protein over expression plays an important role in the genesis of this type of cancer in Brunei Darussalam.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1559-1561
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• 2002

적외선 확산반사형 결정화유리를 응용한 레이저 여기용 공진기를 제작하여 미세구조 분석 및 레이저 여기 효율특성을 조사하였다. 출발물질로는 Cordierite를 주결정상으로 하는 MAS(MgO, $Al_2O_3$, $SiO_2$) 3성분계 조성에 결정화 유도용 조핵제로 $TiO_2$를 첨가하였으며, 형성된 유리 용융물을 흑연제 몰드에 부어 공진기를 제조하였다. 용융물 중 일부를 2단계 열처리를 행하여 상분석을 실시한 결과 Cordierite($2MgO{\cdot}2Al_2O_3{\cdot}5SiO_2$)와 Rutile($TiO_2$)이 주결정상으로 관찰되었으며, 열처리 온도를 변화시켜 생성된 입자의 크기에 따른 확산반사율간의 관계를 조사한 결과, $1100{\sim}1200nm$에서 열처리된 시편의 경우 $500{\sim}2200nm$의 영역에서 95% 이상의 확산반사율을 나타내었다. 대표적인 고체레이저인 Nd:YAG의 경우, $700{\sim}900nm$ 파장이 주흡수대이며, 이를 결정화유리로 제조된 공진기의 레이저 효율특성실험에 이용하였다. 수냉 및 단일 펄스의 조건에서 $1.7{\sim}1.9%$의 효율을 나타내었다.