http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
장준경 ( Joon Kyung Jang ),석승훈 ( S. Hun Seog ),김준석 ( Joon Seok Kim ) 한국금융학회 2007 金融學會誌 Vol.12 No.1
본 연구는 2002년 11월부터 시행되고 있는 공정공시제도가 당초 도입 취지대로 잘 기능하고 있는지를 검증하기 위하여 영업이익 공시시점에서의 주가 및 거래량 반응을 살펴보았다. 본 연구로부터 도출된 결과를 정리해 보면 다음과 같다. 첫째, 공정공시 도입 이후에는 호재정보와 악재정보 모두에서 사건일을 전후한 기간 동안 통계적으로 유의한 주가반응이 나타난 반면 공정공시 도입 이전에는 호재정보에서만 유의한 주가반응이 도출되어 공정공시 도입으로 정보효과가 개선되었음을 보이고 있다. 둘째, 공정공시 도입 이후 호재정보에 대한 주가변동성과 악재정보에 대한 거래량변동성이 낮아졌다. 이는 공정공시제도가 도입 당시에 우려했던 정보공개 지연 등의 부작용 없이 정보의 비대칭성을 해소하는 긍정적인 역할을 수행하고 있음을 말해준다. 셋째, 악재정보가 호재정보에 비하여 공시일 전후의 주가변동성이 큰 것으로 나타나 악재정보가 정보지연의 부작용을 초래할 수 있는 정보의 속성을 지니고 있는 것으로 판단된다. 마지막으로 확실성이 높은 잠정정보와 불확실성이 높은 예측정보의 주가반응을 비교해 보았는데 호재정보에 대해서는 잠정정보에 대한 반응이 크게 나타났으나 유의성을 찾지 못하였고 악재정보에 대해서는 예측정보에 대해 더 큰 주가반응이 나타났다. 이는 악재정보를 자발적으로 공시한 데에 따른 투자자의 과민반응으로 해석된다. This study focuses on analyzing the information effects to review the role of Regulation Fair Disclosure (Reg. FD) since the enforcement of Reg. FD in November 2002. The results of this research are as follows. First, in the post Reg. FD period, the results show that there are stronger abnormal return and trading volume responses over a 3-day period (-1, +1) compared to the new regulation before. However, abnormal return and trading volume responses are also observed in a statistically significant manner in the post-event day. Second, in the post Reg. FD period, stock price and trading volume fluctuations caused by disclosure of companies around the time of shareholders` meeting have decreased compared to the new regulation before. Third, bad news has demonstrated significantly bigger range of stock fluctuations than good news around around the time of shareholder`s meeting.
한진석,장준경,이현철,Han, Jinseok,Jang, Junkyung,Lee, Hyun Chul 한국방사성폐기물학회 2020 방사성폐기물학회지 Vol.18 No.1
The Graphite Isotope Ratio Method (GIRM) can verify non-proliferation of nuclear weapon by estimating the total plutonium production in a graphite-moderated reactor. Using the reactor, plutonium is generated and accumulated through the <sup>238</sup>U neutron capture reaction, and impurities in the graphite are converted to nuclides due to the nuclear reaction. Therefore, the amount of plutonium production and concentration of the impurities are correlated. However, the plutonium production cannot be predicted using only the absolute concentration of the impurities. It can only be predicted when the initial concentration of the impurities is obtained because the concentration, at a certain time, depends on it. Nevertheless, the ratios of the isotopes in an element are known regardless of the impurity of an element in the graphite moderator. Thus, the correlation between the isotope ratio and amount of plutonium produced helps predict plutonium production in a graphite-moderated reactor. Boron, Lithium, Chlorine, Titanium, and Uranium are known as indicator elements in the GIRM. To assess whether the correlation between the indicator isotope and amount of plutonium produced is independent of the initial concentration of the impurities, four different impurity compositions of graphite were used. <sup>10</sup>B/<sup>11</sup>B, <sup>36</sup>Cl/<sup>35</sup>Cl, <sup>48</sup>Ti/<sup>49</sup>Ti, and <sup>235</sup>U/<sup>238</sup>U had a consistent correlation with the cumulative plutonium production, regardless of the initial impurity concentration of the graphite, because these isotopes were not generated through the nuclear reaction of other elements. On the other hand, the correlation between <sup>6</sup>Li/<sup>7</sup>Li and plutonium production depended on the initial concentration of the impurities in graphite. Although <sup>7</sup>Li can be produced through the neutron capture reaction of <sup>6</sup>Li, the (n, α) reaction of <sup>10</sup>B was the major source of <sup>7</sup>Li. Therefore, the initial concentration of <sup>10</sup>B affected the production of <sup>7</sup>Li, making Li unsuitable as an indicator element for the GIRM.
입자 크기 분포가 금 콜로이드의 광학성질에 미치는 영향에 대한 이론 연구
김효정,장준경,Kim, Hyo-Jeong,Saha Leton Chandra,Jang, Joon-Kyung 대한화학회 2007 대한화학회지 Vol.51 No.5
크기 분포를 가진 금 나노 입자 콜로이드의 소광 스펙트럼을 미 이론으로 계산하고 실험과 비교하였다. 입자 크기 분포를 고려한 계산이 크기 분포를 고려하지 않은 계산보다 실험과 더 가까움을 확인하였다. 최소 자승법을 이용하여 실험에서 얻은 소광 스펙트럼으로부터 입자 크기 분포를 이론적으로 도출하였다. 이렇게 얻은 입자 크기는 입자 지름이 10에서 28 나노미터인 경우 투과전자현미경 분석 결과와 잘 일치하였다. Mie theory has been used to calculate the extinction of a gold nanoparticle in water by varying its diameter from 1 to 1000 nm. Utilizing this size-dependent theoretical spectrum, we have calculated the extinction spectrum of a colloidal gold by taking into account the size distribution of particle. Such calculation is in better agreement with experiment than the calculation without considering the size distribution. A least-squares fitting is used to deduce the size distribution from an experimental extinction spectrum. For particles with their diameters ranging from 10 to 28 nanometers, the fitting gives reasonable agreement with the size distribution obtained from tunneling electron microscope images.
Lattice Boltzmann Study of the Water Droplet on a Surface Corrugated with Nanopillars#
Jihye Jang,박성우,김효정,Mohammad A. Matin,Zhengqing Zhang,장준경 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.3
Using the lattice Boltzmann method, we simulated a water droplet on a surface covered with rectangular or parabolic pillars. With increasing spacing between the pillars, the transition from the Cassie to Wenzel states of the droplet was observed. The critical spacing at which the transition occurs and the contact angle of droplet were compared with those obtained from the macroscopic theories of Cassie and Wenzel. The present simulation revealed intermediate states where the droplet was partially impaled by the pillars. Even in the Cassie state, the droplet significantly penetrated down in the gap between the parabolic pillars.
이산 쌍극자 근사를 이용한 금-은 합금 나노입자의 소광 스펙트럼 계산
이희미,장준경,Lee, Hee-Mi,Chandra, Saha Leton,Jang, Joon-Kyung 대한화학회 2007 대한화학회지 Vol.51 No.2
By using the discrete-dipole approximation, we computed the extinction spectrum of a gold-silver alloy nanoparticle. We have examined how the surface plasmon resonance changes with respect to the variation in the composition of the alloy particle. As the fraction of silver increases for a 10nm particle, the peak position of the extinction spectrum blue-shifts linearly. The intensity of the peak however increases exponentially with increasing the silver fraction. These results are in accord with the previous experimental results. 이산 쌍극자 근사를 이용하여 수용액상의 금-은 합금 나노입자의 표면 플라즈몬 공명 스펙트럼을 계산하였다. 직경 10 나노미터의 금-은 합금 입자의 경우에 스펙트럼의 최대 소광 파장이 합금의 은 성분이 높아짐에 따라 선형적으로 짧은 파장대로 이동하며 최대 소광 세기는 지수적으로 증가함을 관측하였다. 이러한 계산결과는 실험 결과들과 잘 일치하는 것을 확인하였다.
분자동역학을 이용한 계층 구조를 갖는 표면의 소수성에 대한 연구
권태우(Tae Woo Kwon),장준경(Joonkyung Jang),Matthew Stanley Ambrosia,하만영(Man Young Ha) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12
Using all-atom molecular dynamics simulation, we investigated the wetting behavior of a water droplet on a surface texturized with nanoscale pillars. We studied the surfaces with nonhierarchical and hierarchical roughnesses by systematically varying the pillar height. A surface decorated with a hierarchical roughness showed an enhanced hydrophobicity in that the droplet on such a surface prefers the Cassie-Baxter state over the Wenzel state. A hierarchical roughness also gave an enhanced contact angle of a droplet. Even a hydrophilic surface (contact angle is < 90°) turned hydrophobic (contact angle > 90°) with a hierarchical roughness on it. We show the adhesion energy of a droplet to its underlying surface is correlated with the contact angle and therefore is a fundamental measure of the wettability of the