• Title/Summary/Keyword: HBr

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A Comparison Study of Several Robust Regression Estimators under Various Contaminations (다양한 오염 상황에서의 여러 로버스트 회귀추정량의 비교연구)

  • 김지연;황진수;김진경
    • The Korean Journal of Applied Statistics
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    • v.17 no.3
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    • pp.475-488
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    • 2004
  • Several robust regression estimators are compared under contamination. Symmetric and asymmetric contamination schemes are used to measure the variance and MSE of regression estimators. Under asymmetric contamination depth-based regression estimator, especially projection based regression estimator(rcent) outperforms the rest and under symmetric contamination HBR performs relatively well.

A study of the GaN etch properties using inductively coupled Cl$_2$-based plasmas (유도 결합형 Cl$_2$계 플라즈마를 이용한 GaN 식각 특성에 관한 연구)

  • 김현수;이재원;김태일;염근영
    • Journal of Surface Science and Engineering
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    • v.32 no.2
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    • pp.83-92
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    • 1999
  • GaN etching was performed using planar inductively coupled $Cl_2$-based plasmas and the effects of main process parameters on the characteristics of the plasmas and their relations to GaN etch rates were studied. Also, the GaN etch mechanism was investigated using a Langmuir probe and optical emission spectroscopy (OES) during the etching, and X-ray photoelectron spectroscopy (XPS) of the etched surfaces. The GaN etch rates increased with the increase of chlorine radical density and ion energy, and a vertical etch profile haying the etch rate close to 4000 $\AA$/min could be obtained. The addition of 10% Ar to $Cl_2$ gas increased the GaN etch rate and the addition of Ar (more than 20%) and HBr generally reduced the GaN etch rate. The GaN etch rate appeared to be more affected by the chemical reaction between Cl radicals and GaN compared to the physical sputtering itself under the sufficient ion bombardments to break GaN bonds.

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Tool for Analyzing Activity of Evacuating and Supporting People Where are you now? Are you alright? -

  • Hayashida, Yukuo;Kiyota, Masaru;Mishima, Nobuo;Oh, Yong-sun;Yoo, Jaesoo
    • Proceedings of the Korea Contents Association Conference
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    • 2016.05a
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    • pp.247-248
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    • 2016
  • To investigate activities in the evacuated situation of people, the measurement system is newly constructed, that composed of a wearable sensor device of heart beats rates and mobile devices like an Android smartphone with a bluetooth low energy (BLE) connection. Smartphone not only displays the heart beats variation (HBR) and the current location of evacuation person by Global Positioning System (GPS), but also exports the CSV formatted file that would be used for further analyzing the activity of person in detail. As an example of the application of this system, we show the case of evacuation routes for elderly person in Hizen-Hamashuku Area, Saga Prefecture. Using the proposed measuring system, the activities of evacuates can be clearly shown on the map of Geospatial Information System (GIS).

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Synthesis of 5-bromouracil-$Br^{82}$ by Isotopic Exchange Method (Isotopic Exchange 에 依한 5-bromouracil-$Br^{82}$의 合成)

  • Pyun, Hyung-Chick;Kim, Jae-Rock
    • Journal of the Korean Chemical Society
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    • v.8 no.2
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    • pp.39-42
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    • 1964
  • As the bromination method with $Br_2^{82}$ for the synthesis of 5-bromouracil-$Br^{82}$ gave products with considerable impurities, e. g. uracil etc. an attempt to produce pure one by isotopic exchange method was performed. Bromide-82 ion such as $NH_4Br^{82}$ or $HBr^{82}$ undergoes no isotopic exchange with 5-bromouracil-Br. However, isotopic exchange between $NH_4Br^{82}$ and $Br_2$, and between $Br_2^{82}$ and 5-bromouracil-Br were too fast to determine the rate. The result indicated that this method can be used in the production of pure 5-bromouracil-$Br^{82}$. It was also found that the use of reducing agent to maintain $Br^{82}$ as bromide form was unnecessary on $NH_4Br^{82}$ production from reactor.

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Alterations in Motor Activity Induced by High Dose Oral Administration of Dextromethorphan Throughout two Consecutive Generations in Mice

  • Kim, Hyoung-Chun;Jhoo, Wang-Kee
    • Archives of Pharmacal Research
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    • v.18 no.3
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    • pp.146-152
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    • 1995
  • To achieve a better understanding of the effects on behavioral safety caused by possible neuroprotective doses (50 mg/kg, p.o.) of dextromethorphan HBr (DM), several motor activity measures were monitored in two generations of mice through a long-term period of ten months. Adult male mice (G1), in the presence of DM, developed behavioral tolerance after an initial suppression period. Prenatally exposed, second generation (G2) mice formed two groups, prenatal exposure alone (G2C) and prenatally exposed with additional postnatal exposure (G2T). In the presence of DM, group G2T was characterized by significant behavioral impairment; while G2C exhibited behavioral activation. These results suggest that more attention should be given to the prenatal effects of DM on a developing organism.

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Synthesis of 3-Amino-1,4-dihydropyridine Derivative via an Intramolecular Rearrangement of 1,4-Dihydropyridine-3-hydroxamate

  • Suh, Jung-Jin;Hong, You-Hwa;Bae, Myn
    • Archives of Pharmacal Research
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    • v.14 no.4
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    • pp.319-324
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    • 1991
  • 2,6-Dimethyl-4-(3'-nitrophenyl)-3-methoxylaminocarbonyl-1,4-dihydropyridine-5-carboxylic acid methylester, 3b reacted with 2-cyanoethanol or benzylalcohol to give the corresponding cyanoethylurethane compound 6c in 40.6% yield and benzylurethane compound 6d in 32% yield. The cyanoethylurethane 6c was hydrolized in ethanolic NaOH to give 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-amino-5-carboxylic acid 5-methyl ester. HCl 8 in 64.8% yield. Another acid hydrolysis of benzylurethane 6d gave 2,6-dimethyl-4-(3'-nitrophenyl)-1,4-dihydropyridine-3-amino-5-carboxylic acid 5-methylester. HBr 11 in 54.7% yield.

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Etch characteristics of high-k dielectrics thin film by using inductively coupled plasma (유도결합 플라즈마를 이용한 고유전율 박막의 식각특성)

  • Kim, Gwan-Ha;Woo, Jong-Chang;Kim, Kyoung-Tae;Kim, Dong-Pyo;Lee, Cheol-In;Kim, Chang-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.140-141
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    • 2007
  • 반도체 소자의 공정에 있어서 device scaling으로 인한 고유전 게이트 산화막 (high-k dielectics thin film)의 공정 개발 확보 방안이 필요하다. 본 논문에서는 유도결합 플라즈마를 이용하여 고유전율 박막을 식각하였다. CF4, SF6 등의 가스에서 금속-F, 금속-S 결합의 낮은 휘발성으로 인하여 시료 표면에 잔류하여 낮은 식각률을 보이며 측벽 잔류물을 형성하였으며, HBr, Cl 기반 플라즈마에서 금속-Br, 금속-Cl 결합은 시료 표면으로부터 탈착이 용이하여 효과적인 식각이 이루어짐을 확인할 수 있었다.

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A Synthesis of Solanone (솔라논의 합성)

  • Yong Tae Kim;Kwang-Kyu Yang;Kun Soo Kim;Sung Chul Shin
    • Journal of the Korean Society of Tobacco Science
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    • v.10 no.2
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    • pp.137-139
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    • 1988
  • A total synthesis of solanone was investigated. 4-Cyano -2-isopropylbutanal was treated with methallyl iodide in the presence of metallit tin, alominium and HBr to obtain 7-cyano-5-isopropyl-4-hydroxy-2-methyl-1-heptene, which was contacted with phosphorus oxychloride, followed by methylation of dienonitrile, yielded the solanone.

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$CO_2$ Laser Induced Decomposition of 1-Bromo-3-Chloropropane

  • Byoung Soo Chun;Nam Woong Song;Kwang Yul Choo
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.214-220
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    • 1990
  • We have studied the Infrared Multiphoton Dissociation (IRMPD) of 1-bromo-3-chloropropane by using the pulsed $CO_2$ laser. The product yields and the HCl/HBr branching ratios in IRMPD of $BrCH_2CH_2CH_2Cl$ are studied under the focused beam geometry as a function of buffer gas (He) pressure, laser energy, and photolysing wavelength. It is observed that the total dissociation yield has a laser energy dependence of 1.8-2.0 power order and the branching ratio is very slightly dependent on the pulse energy for the laser lines employed. The dependences of total dissociation yield and branching ratio on the buffer gas pressures show that the dissociation yield monotonically decreases and the branching ratio slightly decreases with the increase of the buffer gas pressure. The Energy-Grained Master Equation (EGME) was applied to explain the laser pulse energy and the buffer gas pressure(He) dependence of the dissociation yield and the branching ratio.

Effect of Uncoordinated Tertiary Nitrogen Atoms in Hexaaza Macrocyclic Nickel(II) Complexes on Axial Binding of Anions and Water in Acidic Solutions

  • 김성진;최장식;강실걸;김창수;백서병현
    • Bulletin of the Korean Chemical Society
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    • v.16 no.3
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    • pp.217-221
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    • 1995
  • Axial coordination of anions or water to the square-planar nickel(Ⅱ) complexes of the hexaaza macrocyclic ligands 1, 2, and 3, which contain two extra uncoordinated tertiary nitrogens, have been investigated in aqueous solutions containing HX (X=Cl-, Br-, NO3-, or ClO4-) and/or NaX. The nickel(Ⅱ) complexes exist in the acidic solutions as equilibrium mixtures of the square-planar [Ni(L)]2+ (L=1, 2, and 3) and octahedral species [Ni(H2L)X2]2+ (H2L=diprotonated form of L). Some octahedral complexes have been isolated and characterized. The solution behaviors of the complexes indicate that the formation of the octahedral complexes are significantly promoted by the protonation of the uncoordinated tertiary amines. The proportion of the octahedral complexes depends on the type of acid, and increases in the order of HBr < HNO3 < HCl.