• 보존과학회지
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• 제26권1호
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• pp.13-24
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• 2010

부여 능산리사지 출토 누금세공 유물 4점을 대상으로 기초적인 재질특성과 미세조직을 분석하여 각각에 대한 제작방법을 살펴보았다. 이 결과 모두 22.7K 이상의 비교적 높은 순도를 나타냈으며 일부 유물에서는 금과 은이 일정 비율로 합금된 상태를 보였다. 표면을 장식한 금선은 0.2~0.8mm 두께를 보이고 다양한 단면형태를 나타냈다. 금입자는 2개 또는 3개가 접합되어 부착된 상태로, 0.3~0.8mm의 직경을 나타냈다. 금세선과 금입자의 표면 접합부에서는 땜의 잔재가 관찰되었으며 성분분석을 통해 금 땜의 사용 가능성을 확인하였다. 또한 진사(HgS), 먹과 같은 안료를 감장하여 표면을 장식한 모습도 보였다.

• 한국조경학회지
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• 제30권6호
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• pp.26-37
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• 2003

Urban park are indispensable elements of contemporary cities. However, the structure and culture of contemporary cities is currently changing. There are prevalent discourses that Olmstedian parte are no longer relevant to our new societies and cultures. New kinds of parks have emerged with different forms and functions. In order to propose a new paradigm for parks in the 21st century, we need to look back to the origin of modem parks, which is to say, Olmstedian parte. This paper aims to trace the background of park movements in the 19th century America and to identify and describe Olmsted's idea of urban parks. In addition, the paper will clarify the limitations and reinterpret the meaning of Olmsted's idea of urban parks. One idea behind the development of urban parte was to mitigate urban problems such as public health, alcoholism violence and class conflicts in 19th century industrial cities. The aim of urban park was partially achieved at that time. However, those parse did not serve the use of diverse classes. Olmstedian parks were designed for passive and civilized recreation, and lower classes were more attracted by active theme parks and areas such as Coney Island and John Wood. The strengths of Olmsted's idea of urban parte can be outlined as follows: First, designing parte goes beyond shaping physical lands to embrace social reforms. This means that park designers should have a critical understanding of society and culture. Also, landscape designers should have a bold vision for the future. Without such a vision and social agenda, landscape architects cannot postulate alternative possibilities through engaging in new practices. Second, Olmsted successfully adapted British landscape aesthetic ideas such as the picturesque, the sublime and the beautiful into an American context. Finally, his vision and idea of urban parks show us that landscape architecture is not just technical work, but that it can create a locus to engage a new cultural praxis by inventing cultural products - parks.

• 정보처리학회논문지B
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• 제16B권5호
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• pp.347-358
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• 2009

손동작을 인식하는 연구가 오랫동안 이뤄져 왔지만 대개의 시스템들이 값비싼 깊이 카메라를 사용하거나 여러 개의 카메라를 사용해 분석하는 등 그 비용이 크며 작동이 가능한 작업 공간이 지극히 제한적이었다. 본 논문에서는 가전제품을 원격 제어하기 위한 목적으로 두 개의 회전 모터를 사용해 작업 공간을 확대하고 저렴한 일반 카메라를 사용해서 효율적으로 손동작을 인식하기 위한 시스템을 제안한다. 이 시스템은 입력된 카메라의 자세 정보와 이미지상의 2차원적 손가락 위치 정보를 이용하여 3차원 궤적을 추정하고 이를 동작 평면으로 투영시켜 의미 있는 선형 동작 패턴으로 복원한다. 또한 본 논문에서는 개발된 시스템을 테스트하여 주어진 목적에 맞는 정확도를 가지는 작업 영역을 정의한다.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.639-644
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• 2011

A simple and highly sensitive chemiluminescence method to determine norfloxacin (NFLX) has been proposed by measuring the chemiluminescence (CL) intensities using a flow injection (FI) system. The CL intensity of the luminol-$H_2O_2$ system is strongly enhanced by the addition of Cu (II) in alkaline condition. The CL intensity is substantially increased after the injection of NFLX into the luminol-$H_2O_2$-Cu (II) system. The enhancement effect is attributed to a catalytic effect of Cu (II) due to the interaction with NFLX which forms a complex with the catalyst. Under the optimal conditions, the sensitizing effect of the CL intensity is proportional to the concentration of NFLX in the range of $1.5{\times}10^{-9}-5.9{\times}10^{-7}molL^{-1}$ (r = 0.9994) with a detection limit ($3{\sigma}$) of $2.98{\times}10^{-10}molL^{-1}$. The proposed method had good reproducibility with the relative standard deviation (RSD, n = 5) of 1.6% for $1{\times}10^{-7}molL^{-1}$ of NFLX. The possible reaction mechanism of the CL reaction is also discussed. This method has been successfully applied for the determination of trace amount of NFLX in pharmaceutical preparations and serum samples.

• 한국환경보건학회지
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• 제31권6호
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• pp.498-503
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• 2005

Stability of soybean isoflavone isomers according to extraction conditions such as temperature, pH, and extracting solvents was investigated. Heating induced three chemical reactions to occur for malony1 derivatives of isoflavones, namely decarboxylation of malony1 groups into acety1 derivatives, deesterification of malony1 residues, and hydrolysis of $\beta$-glycosidic bonds. Among the twelve isoflavone isomers, change in concentrations of acety1glycosides were most pronounced: Acety1 derivatives were present only in trace amounts in unheated hypocotyls, but the content increased dramatically during heating. As for the glycosides, concentrations of daidzin and glycitin increased due to heat treatment, though that of genistin remained almost unchanged. Heat decomposition rates and the patterns differed among the three malony1 derivatives. After 120 min at $80^{circ}C$, the relative concentrations of daidzin, glycitin and genistin were increased from $9.2\%$, $12.4\%$ and $3.3\%$ to $19.3\%$, $21.9\%$ and $6.2\%$, respectively. When crude isoflavones were solubilized in glycine buffer (pH 10.0) and incubated at $80^{circ}C$, deesterification occurred faster than at pH 7.0. When the pH of isoflavone solution was increased, the malony1glycosides were hydrolyzed to their respective glycosides at increased rate. Both acetyl and aglycone forms were unchanged and only de-esterification reactions occurred. At the acidic pH, malonylglycosides were much stable both at 60 and $80^{circ}C$. However at pH 10, $80^{circ}C$ and 1 hr, $75-80\%$ of malonylglycosides were transformed to their deesterified glycosides. When isoflavones were extracted with $60\%$ aqueous ethanol at $60^{circ}C$, isoflavone isomers were stable and the deesterification reactions did not occur in these conditions. However, at $80^{circ}C$ deesterification of malonyiglycosides occurred significantly with $15-20\%$ of malonylglycosides being hydrolyzed into their respective glycosides. This experiment showed that malonylglycosides undergo decomposition when heated or exposed to alkaline conditions. Also, aqueous ethanol was preferred to aqueous methanol as solubilizing media for obtaining extract with minimum degradation of malonylglycosides.

• ALGAE
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• 제35권2호
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• pp.167-176
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• 2020

Iodine exists as a trace element in seawater, with total iodine being generally constant at about 0.45-0.55 μM. Almost all of this iodine occurs in two main forms: iodate and iodide. Iodate is the thermodynamically stable form under normal seawater conditions, and thus should be the only iodine-containing species in the water column. However, iodate concentrations are found to vary considerably, being generally greater at depth and lower at the surface, while iodide concentrations follow the reverse pattern, being anomalously accumulated in the euphotic zone and decreasing with depth. The fact that iodide concentrations follow a depth dependence corresponding to the euphotic zone suggests that biological activity is the source of the reduced iodine. Nonetheless, the nature and source of iodate reduction activity remains controversial. Here, using a combination of field and laboratory studies, we examine some of the questions raised in our and other previous studies, and seek further correlations between changes in iodine speciation and the presence of marine macro- and microalgae. The present results indicate that microalgal growth per se does not seem to be responsible for the reduction of iodate to iodide. However, there is some support for the hypothesis that iodate reduction can occur due to release of cellular reducing agents that accompany cell senescence during phytoplankton bloom declines. In addition, support is given to the concept that macroalgal species such as giant kelp (Macrocystis pyrifera) can take up both iodide and iodate from seawater (albeit on a slower time scale). We propose a mechanism whereby iodate is reduced to iodide at the cell surface by cell surface reductases and is taken up directly as such without reentering the bulk solution.

• 한국언론정보학보
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• 제18권
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• pp.305-331
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• 2002

이 논문은 개화기의 언론 수용자운동을 분석하였다. 최근 언론 수용자운동에 대한 기대와 관심이 높아지면서 이에 대한 연구 성과도 적지 않게 축적되었다. 그러나 그 대부분의 연구들은 한국 언론사에서 언론 수용자운동의 기원을 1960년대의 언론윤리위원회 파동으로 잡고 있다. 그러나 그 이전의 한국 언론사에서도 우리가 수용자운동이라는 범주로 포괄할 수 있는 역사적 사건들이 분명히 존재하고 있다. 본 논문은 이러한 입장에서 개화기의 두 사례를 분석하고 있다. 박문국 방화사건과 <<황성신문>> 및 <<제국신문>> 살리기 운동이 그것이다. 이 사례들은 언론에 대한 인식을 바탕으로 하여 수용자들의 의견이 집단적으로 표출되고 행동으로 이어졌다는 점에서 언론 수용자운동으로 볼 수 있을 것이다. 이러한 논의를 통하여 우리는 개화기의 언론에서도 수용자운동이 나타나기 시작했음을 알 수 있다. 이와 같은 사실은 한국사회에서 수용자운동의 역사적 뿌리가 그만큼 깊고 오래되었음을 말해 주는 것이며 이는 또한 언론 수용자의 중요성을 다시금 확인시켜 주는 것이다.

• 한국토양비료학회지
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• 제48권2호
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• pp.73-80
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• 2015

Arsenic which is found in several different chemical forms and oxidation states and causes acute and chronic adverse health effects is a toxic trace element widely distributed in soils and aquifers from both geologic and anthropogenic sources. Arsenic which has a mysterious ability to change color, behavior, reactivity, and toxicity has diverse chemical behavior in the natural environment. Arsenic which has stronger ability to readily change oxidation state than nitrogen and phosphorus due to a consequence of the electronic configuration of its valence orbitals with partially filled states capable of both electron donation and acceptance although the electronegativity of arsenic is greater than that of nitrogen and similar to that of phosphorus. Arsenate (V) is the thermodynamically stable form of As under aerobic condition and interacts strongly with solid matrix. However, it has been known that adsorption and oxidation reactions of arsenite (III) which is more soluble and mobile than As(V) in soils are two important factors affecting the fate and transport of arsenic in the environment. That is, the movement of As in soils and aquifers is highly dependent on the adsorption-desorption reactions in the solid phase. This article, however, focuses primarily on understanding the fate and speciation of As in soils and what fate arsenic will have after it is incorporated into soils.

• 정보처리학회논문지A
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• 제9A권4호
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• pp.563-572
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• 2002

성능감시기는 분산처리 환경에서 프로그램의 성능을 추적하고 평가하기 위해 필수적인 것이다. 성능감시기는 출력방법에 따라 오프라인과 온라인으로 나눌 수 있다. 오프라인성능감시기는 프로그램이 종료된 후에 그 성능을 분석하는 것이고, 온라인 성능감시기는 프로그램의 수행 중에 분석하는 것이다. 따라서 프로그램의 빠른 분석과 디버깅을 위해서는 온라인 기능이 필수적이다. JaNeC은 Java로 구현된 분산처리 환경으로 이를 위한 오프라인성능감시기가 포함되어 있다. 그러나 이 성능감시기로는 JaNeC에서 수행되는 프로그램을 효율적으로 분석할 수 없다. 따라서, 본 논문에서는 JaNeCe에서 수행되는 프로그램의 빠른 분석과 디버깅을 위해 온라인 성능감시기를 설계하고 구현하는 것에 대해서 설명한다. 이 온라인 성능감시기는 분석하고자 하는 프로그램에 영향을 최소화하도록 설계되었으며, 효율적인 프로그램 분석을 위해 다양한 형태의 그래픽 출력을 제공한다. 또한 프로그램이 종료된 이후에도 다시 분석할 수 있도록 하기 위해 오프라인 성능감시기와의 인터페이스도 제공한다.

• Journal of the Korean Physical Society
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• 제73권10호
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• pp.1420-1430
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• 2018

We investigate an entangled system, which is analogous to a composite system of a black hole and Hawking radiation. If Hawking radiation is well approximated by an outgoing particle generated from pair creation around the black hole, such a pair creation increases the total number of states. There should be a unitary mechanism to reduce the number of states inside the horizon for black hole evaporation. Because the infalling antiparticle has negative energy, as long as the infalling antiparticle finds its partner such that the two particles form a separable state, one can trace out such a zero energy system by maintaining unitarity. In this paper, based on some toy model calculations, we show that such a unitary tracing-out process is only possible before the Page time while it is impossible after the Page time. Hence, after the Page time, if we assume that the process is unitary and the Hawking pair forms a separable state, the internal number of states will monotonically increase, which is supported by the Almheiri-Marolf-Polchinski-Sully (AMPS) argument. In addition, the Hawking particles cannot generate randomness of the entire system; hence, the entanglement entropy cannot reach its maximum. Based on these results, we modify the correct form of the Page curve for the remnant picture. The most important conclusion is this: if we assume unitarity, semi-classical quantum field theory, and general relativity, then the black hole should violate the Bekenstein-Hawking entropy bound around the Page time at the latest; hence, the infinite production arguments for remnants might be applied for semi-classical black holes, which seems very problematic.