• Economic and Environmental Geology
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• v.19 no.3
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• pp.225-230
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• 1986

Various interpretations on the boundary between the $Okch{\check{o}}n$ system and the Great Limestone series of the $Chos{\check{o}}n$ system, and on the geologic structure and stratigraphy of the $Okch{\check{o}}n$ system have been yielded by the previous studies, and they are still in hot debate. The present work has mainly studied on the boundary between the $Okch{\check{o}}n$ and $Chos{\check{o}}n$ systems in the south of $Jech{\check{o}}n$, and the geology in its vicinity to clarify the previous misinterpretations if any on the geologic structure and in trun stratigraphy of the area concerned. The boundary between the $Okch{\check{o}}n$ system and the Great Limestone series of the $Chos{\check{o}}n$ system has been thought to be (1) gradational relation which means two systems are the same formation, (2) unconformable relation in which the $Okch{\check{o}}n$ system overlies the $Chos{\check{o}}n$ system, (3) unconformable relation in which the $Chos{\check{o}}n$ system overlies the Okchon system indicating that the age of the $Okch{\check{o}}n$ system is Precambrian, and (4) fault contact in which the $Okch{\check{o}}n$ system of Precambrian age comes in contact with the $Chos{\check{o}}n$ system of Cambro-Ordovician age. The present study clearly found that the relationship between the two systems is a fault zone contact. Shear zone of a width of 300 to 400m is developed, and andesitic volcanics and basic dikes are intruded along the fault zone. This fault contact is exactly the north extension of the Bonghwajae fault, which was denominated long time ago by two of the present authors. The eastern side of the fault has been uplifted so that the $S{\check{o}}changri$ formation of the $Okch{\check{o}}n$ system cropped out in the zone of the Great Limestone series. All the previous workers thought that the $S{\check{o}}changri$ formation rests on the Great Limestone series, but the present study found an overthrust having a strike of $N8^{\circ}E$ and dip of $30^{\circ}NW$ between them, and the $S{\check{o}}changri$ formation has thrusted over the Great Limestone series at the central part of the study area. In the southern and northern parts of this uplifted $S{\check{o}}changri$ formation, the Great Limestone series rests unconformably on it. In the eastern part of the study area where the Mt. Dangdu is located and the previous workers thought that the $S{\check{o}}changri$ formation rests on the Great Limestone series, Precambrian basement rock whose age is older than 1720+50 m.y. crops out in the northern part of the east-west trending high angle fault, and the Great Limestone series rests unconformably on the basement.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.5
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• pp.333-343
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• 1997

The cyclone/annular denuder system/filter pack sampling system (ADS) was used to collect the acidic air pollutants in Chongju city. The data set was collected on fifty -eight different days with 24 hour sampling period from October 27, 1995 through August 25, 1996. The chemical species measured were HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$ in the gas phase, and PM2.5( $d_{p}$ ＜2.5 ${\mu}{\textrm}{m}$), S $O_4$$^{2-}$, N $O_3$$^{[-10]}$ and N $H_4$$^{+}$ in the Particulate Phase. Mean concentrations measured for this study were: 0.45 $\mu\textrm{g}$/㎥ for HN $O_3$, 3.39 $\mu\textrm{g}$/㎥ for HN $O_2$, 26.4 $\mu\textrm{g}$/㎥ for S $O_2$, 3.83$\mu\textrm{g}$/㎥ for N $H_3$, 44.2 $\mu\textrm{g}$/㎥ for P $M_{2.5}$, 8.22 $\mu\textrm{g}$/㎥ for S $O_4$$^{2-}$, 3.63 $\mu\textrm{g}$/㎥ for N $O_3$$^{[-10]}$ , and 2.84 $\mu\textrm{g}$/㎥ for N $H_4$$^{- }$. HN $O_3$ and N $H_3$ were higher during the summer. However, HN $O_2$ and S $O_2$ were higher during the fall and winter. P $M_{2.5}$ , S $O_4$/ sup 2-/ and N $H_4$$^{+}$ were not showed seasonal variations, but N $O_3$$^{[-10]}$ was higher in the winter.ter.r.

• Cross-Cultural Studies
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• v.50
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• pp.225-259
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• 2018

In this study, according to the Institut d'Estudis Catalan, it is noted that the traditional Catalan time telling system is essentially based on delineating time by the use of the 'quarts (=quarters)' of an hour. In this fasion, to tell the time 8:15, 8:30 and 8:45 they use '${\acute{E}}s$ un quart de nou.,' '$S{\acute{o}}n$ dos quarts de nou.,' and '$S{\acute{o}}n$ tres quarts de nou.,' but do not use constructions such as '$S{\acute{o}}n$ les vuit i quinze.,' '$S{\acute{o}}n$ les vuit i trenta/mitja.,' '$S{\acute{o}}n$ les vuit i quaranta-cinc.,' because these expressions are considered to be as dialectal variants or international notation-based variants. Moreover, the traditional Catalan time telling system does not use cardinal numbers, except in the case of 'cinc (five)' and 'deu (ten).' These linguistic phenomenon cause the invention of a unique Catalan digital watch, and has noted special designs for the creation of a Catalan analogue watch. For this reason, the quarter system in colloquial Catalan provokes an enormous interpretative ambiguity in daily routine expressions with 'quarts' like '$S{\acute{o}}n$ quarts of nou.' or 'entre dos i tres quarts' whose meaning is not delineated between sixteen and forty-four minutes. We will argue that the traditional Catalan time telling expressions do not have the use of the subtractive system, and the fraction word 'quart' lacks a specific meaning of fifteen minutes because the Catalan word 'quart' is etymologically related to the classical public bell system, not definitively to the traditional clock system.

• Journal of the Korean Ceramic Society
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• v.26 no.1
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• pp.31-36
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• 1989

In order to synthesize AlN-polytypes from AlN-SiO2-Al2O3 system, composition A (AlN/SiO2/Al2O3=1/0.3/0.05, mole ratio) and composition B(AlN-SiO2-Al2O3=1/0.2/0.05, mole ratio) were used. AlN-polytypes were produced by nitriding the mixture at 175$0^{\circ}C$~190$0^{\circ}C$ under N2 atmosphere. For lower reaction temperature, 15R phase was produced and in the case of higher reaction temperature, AlN phase was only produced. As each composition was heated at 185$0^{\circ}C$ in N2 atmosphere, produced main phases were 15R phase for composition A and 21R phase for composition B respectively. The fracture surfaces of produced reactants showed porous skeleton structure.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.5
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• pp.397-410
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• 1997

An annular denuder filter pack sampling system (ADS) was used to collect acidic air pollutants in Pusan. During the study period (from June 1995 to November 1995), forty eight samples were collected every 12 hours starting from 6:00 in the morning. These samples were devided into two sets of data for day (6:00 a.m.-6:00 p.m.) and night (6:00 p.m.-6:00 a.m.). The chemical species were analyzed for HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$ in the gas Phase, and N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$ and N $H_4$$^{+}$ in the particulate phase. The mean concentrations measured from this study were 0.24, 1.91, 30.07 and 4.24 $\mu\textrm{g}$/㎥ for HN $O_3$, HN $O_2$, S $O_2$ and N $H_3$, respectively. The mean concentrations of N $O_3$$^{[-10]}$ , S $O_4$$^{2-}$ and N $H_4$$^+{\ulcorner}$ were 1.95, 7.36 and 3.48 $\mu\textrm{g}$/㎥, respectively. The mean concentrations of gaseous species except for HN $O_2$ were higher in daytime than in nighttime, but the reverse was true in the particulates except for N $H_4$$^{+}$. +/..

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.21-21
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• 2014

$CrN/Al_2O_3/CrN$ 다층 코팅을 HIPIMS와 ALD간 하이브리드 코팅법을 통해 형성하였다. ALD를 통해 CrN 층에 도입한 $Al2O_3$층의 두께 및 위치가 $CrN/Al_2O_3/CrN$ 다층 코팅층의 미세구조, 표면 거칠기, 기계적 특성 및 화학적 특성에 미치는 영향에 대해 조사하였다. 전체 공정시간은 거의 변화시키지 않고도, ALD를 이용한 $Al2O_3$층의 삽입에 의하여 기계적/화학적 특성이 크게 개선될 수 있음을 확인하였으며, 개선된 특성에 대한 원인에 대해 조사하였다.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.6
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• pp.117-127
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• 1994

In this paper, electrical and reliability properties of N$_2$O oxides, grown at the temperature of 95$0^{\circ}C$ and 100$0^{\circ}C$ to 74$\AA$, and 82$\AA$. respectively, using NS12TO gas in a conventional furnace, have been compared with those of pure oxide grown at the temperature of 850 to 84$\AA$ using O$_2$ gas. Initial IS1gT-VS1gT characteristics of N$_2$O oxides were similar to those of pure oxide, and reliability properties of N$_2$O oxides, such as charge trapping, interface state density and leakage current at low electric field under F-N stress, were improved much better than those of pure oxide. But, with increasing capacitor area. TDDB characteristics of N$_2$O oxides were more degraded than those of pure oxide and this degradation of TDDB characteristics was more severe in 100$0^{\circ}C$ N$_2$Ooxide than in 95$0^{\circ}C$ N$_2$O oxide. The improvement of reliability properties excluding TDDB in N$_2$Ooxides was attributed to the hardness of the interface improved by nitrogen pile-up at the interface of Si/SiO$_2$, but on the other hand, the degradation of TDDB characteristics in N$_2$O oxides was obsered due to the increase of local thinning spots caused by excessive nitrogen at interface during the growth of N$_2$O oxides.

• Journal of KIISE
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• v.42 no.3
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• pp.289-294
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• 2015

The consensus problem is finding a representative string, called a consensus, of a given set S of k strings. Circular strings are different from linear strings in that the last symbol precedes the first symbol. Given a set S of circular strings of length n over an alphabet ${\Sigma}$, we first present an $O({\mid}{\Sigma}{\mid}nlogn)$ time parallel algorithm for finding a consensus of S minimizing both radius and distance sum when k=3 using O(n) threads. Then we present an $O({\mid}{\Sigma}{\mid}n^2logn)$ time parallel algorithm for finding a consensus of S minimizing distance sum when k=4 using O(n) threads. Finally, we compare execution times of our algorithms implemented using CUDA with corresponding sequential algorithms.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.583-587
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• 2000

Depletion kinetics of ground state FeO molecules by $0_2$, $N_2O$ and $N_2$ has been studied at room temperature. The ground state FeO molecules were generated by photolysis of a $Fe$(CO)_5$/M(O_2$, $N_2O)/He$ mixture using an unfocused weak UV laser beam. The formation of ground state FeO molecules was identified by a laser-induced fluorescence (LIF) method. The intensity distribution of those undisturbed rotational lines suggests that the rotational temperature of the ground state FeO molecules is lower than room temperature. The LIF intensities of FeO molecules at different partial pressures of $0_2$, $N_2O$ and $N_2$ were monitored as a function of the time delay between the photolysis and probe laser pulses to obtain the depletion rate constants for the ground state FeO. They were 1.7+ 0.2x $10^{-12}$, 4.8 $\pm0.4$ x $10^{-12}$, and $1.4\pm$ 0.2x $10^{-12}cm^3$molecule^{-1}s^{-1}$$ by $0_2$, $N_20$, and $N_2$, respectively.

• Honam Mathematical Journal
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• v.31 no.3
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• pp.381-398
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• 2009

Let $G\;=\;O(k){\times}O(k){\times}O(q)$ and let $M^n$ be a closed G-invariant minimal hypersurface with constant scalar curvature in $S^{n+1}$. Then we obtain a theorem: If $M^n$ has 2 distinct principal curvatures at some point p, then the square norm of the second fundamental form of $M^n$, S = n.