• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.680-683
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• 2006

A one-dimensional planar model is considered of the atmosphere with multi-layer clouds illuminated by a mono-directional parallel flux of solar radiation. A new approach is proposed to radiation transfer modeling and daylight background formation for the atmosphere with such clouds that is represented as a heterogeneous multi-layer system each layer of which is described by different optical characteristics. The influence functions of each layer are determined by solutions of the radiation transfer boundary problem with an external monodirectional wide flux while the contribution of multiple scattering and absorption in the layer is taking into account.

• 천문학회보
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• 제42권2호
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• pp.75.3-75.3
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• 2017

We Investigate dust stripping of Virgo cluster galaxies that are known to suffer HI gas stripping. The gas stripping phenomena of these galaxies may result from either ram pressure induced by the hot intracluster medium or gravitational tidal interactions between galaxies. While much efforts have been made to directly detect gas removed from cluster galaxies, the spatial distributions of dust, which should also be affected, are hardly known. Several previous studies have tried to directly detect the morphology of gas or dust using radio or infrared observations, but such approaches are hard to widely apply because of the limit of observational resolution and sensitivity. In this study, we try a different approach using optical data: measuring the background galaxy reddening by the dust stripped from the Virgo cluster members. Based on optical color excess maps of the background galaxies, we compare the ambient dust distribution with the HI morphology of the Virgo galaxies. We discuss how efficiently dust stripping can be detected with this method and how the stripped dust is associated with the removed gas according to HI gas stripping stage over the sample.

• 천문학회보
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• 제35권1호
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• pp.83.2-83.2
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• 2010

During the formation of cosmic web, collisionless shock waves are produced around and inside the substructures. In these shock waves electrons and ions are accelerated to such high energies that they can produce gamma rays in several ways. Many authors have studied the contribution of shock-induced radiation to the cosmic gamma-ray background. However not all the important physical processes are included in their calculation. By considering more complete physical process, we re-investigate the problem. In our model, the energy distribution of the cosmic rays (CRs) are calculated by widely accepted diffusive shock acceleration model, both primary and secondary CR electrons are included, both inverse Compton scattering and bremsstrahlung process are considered. The difference of the results are discussed.

• 천문학회보
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• 제46권2호
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• pp.72.2-72.2
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• 2021

Cosmic reionization imprints its history on the sky map of the cosmic microwave background (CMB) polarization. Even though mild, the signature of the reionization history during its early phase (z>15) can also impact the CMB polarization. We forecast the observational capability of the LiteBIRD(Lite(Light) satellite for the studies of B-mode polarization and Inflation from cosmic background Radiation Detection), a truly cosmic-variance limited apparatus. We focus on the capability for such an apparatus to probe the partial optical depth of the CMB photons during z>15. We show that LiteBIRD is able to probe this quantity with a modest to high significance, enabling one to tell how efficient the cosmic reionization and star formation were at z>15.

• 직업교육연구
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• 제37권3호
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• pp.113-131
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• 2018

이 연구는 고등학교를 졸업하고 현장에서 일하고 있는 청년노동자의 노동관에 영향을 준 진로발달시기의 다양한 요인들을 탐색하고, 그 요인별 영향력을 분석하는 데 그 목적이 있다. 연구에 활용된 자료는 "한국교육종단연구2005" 패널데이터(panel data)이고, 구체적으로는 7차년도(2011)의 원자료에서 추출한 취업자 303명을 대상으로 분석하였다. 연구결과는 첫째, 청년노동자들의 노동관은 그들의 진로발달시기에 형성된 자아인식 관련 변인의 사회성자아, 가정환경 관련 변인의 부 학력, 그리고 학습동기인 외재적 학습동기와 내재적 학습동기로부터 영향을 받은 것으로 나타났다. 다만, 외재적 학습동기의 경우 향후 노동에 대해 동기와 가치 부여에 소극적이고 부정적인 영향을 미치는 것으로 나타났다. 둘째, 진로발달시기의 자아인식 관련 변인과 가정환경 관련 변인은 학습동기를 매개로 청년노동자의 노동관에 인과관계를 갖고, 영향을 준 것으로 밝혀졌다. 따라서 진로발달시기에 형성된 학습동기는 청년노동자들의 노동관 형성에 매우 의미 있고, 중요한 변인임을 확인하였는 데 의의가 있다.

• 천문학회지
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• 제37권5호
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• pp.517-525
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• 2004

We present an update on our proposal that during the 'quasar era' (1.5 $\le$ z $\le$ 3), powerful radio galaxies could have played a major role in the enhanced global star-formation, and in the widespread magnetization and metal pollution of the universe. A key ingredient of this proposal is our estimate that the true cosmological evolution of the radio galaxy population is likely to be even steeper than what has been inferred from flux-limited samples of radio sources with redshift data, when an allowance is made for the inverse Compton losses on the cosmic microwave background which were much greater at higher redshifts. We thus estimate that a large fraction of the clumps of proto-galactic material within the cosmic web of filaments was probably impacted by the expanding lobes of radio galaxies during the quasar era. Some recently published observational evidence and simulations which provide support for this picture are pointed out. We also show that the inverse Compton x-ray emission from the population of radio galaxies during the quasar era, which we inferred to be largely missing from the derived radio luminosity function, is still only a small fraction of the observed soft x-ray background (XRB) and hence the limit imposed on this scenario by the XRB is not violated.

• Preventive Nutrition and Food Science
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• 제2권4호
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• pp.360-367
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• 1997

The chemistry background of the Maillard reaction focused on pyrazines and factors affecting the reaction products were reviewed. The Maillard reaction, also called a non-enzymatic browning reaction, is quite complex and generates numerous reaction products. In processed foods, it is generally accepted as a key reaction to produce flavor components. Specially, pyrazines possess an important impact character on the roasted foods with other heterocyclic compounds. The Maillard reaction is initiated by condensation between reducing sugar and amino group, and N-glycosylamines are produced via Schiff base with dehydration of water. After the rearrangement of the N-glycosylamines, they follow transformation into deoxyhexosones which are reactive intermediates. Degradation and fragmentation are facilitated by rearranged compounds. By condensation, pyrazine, one of the final Maillard products, is generated as a relatively stable form to provide specific aromas. During the processes of the reaction, chemical or physical environmental parameters affect the formation of the products.

• 한국실내디자인학회논문집
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• 제20호
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• pp.71-77
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• 1999

The purpose of the research is to reveal the process of the formation of modern church architecture in 20th century. In order to do that, neo-gothic architecture which starts in the point of view of ethic in the 19th century will be discussed first. Then the relations between Arts and Crafts Movement and church architecture which is the beginning of modern architecture movement will be revealed. After that, the purpose of Secession's church architecture which tried to separate from old architecture and the formation of background of localistic church architecture which is one of the modern church architecture will be discussed. Based on those discussions, the research in concluded the several characteristics of church architecture which makes it modern architecture. The research is focused to the portions which is related to the church architectures among the architectural conditions so complicated as to be easily confused. And also it is focused the architect those who should be mentioned in the same context and their works.

• 자원환경지질
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• 제32권2호
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• pp.169-175
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• 1999

The water leakage of reservoir embankment usually occurs through water vein, which gives little influence on the embankment in a normal state. However, the embankment can be destroyed when the water level of reservoir increases with heavy rain in summer. Investigating the water vein and its path is therefore very important from the viewpoint of disater prevention and embankment protection. This paper presents survey results of one-meter-depth ground temperature and multi-point temperature logging in an embankment in Japan to delineate water veins and permeable formations. Four water veins have been predicted in the embankment by comparing measured one-meter-depth ground temperatures with the background ones which have no effect of water vein. The multi-point temperature logging was carried out in the borehole drilled at one of the predicted water veins. Depth and thickness of the permeable formation in the borehole can be determined from temperature restoration ratios with elapsed time. From these results we can find that the water leakage of reservoir embankment mainly occurs in sandy soil formation in the embankment.

• Environmental Analysis Health and Toxicology
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• 제11권1_2호
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• pp.49-57
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• 1996

The production of reactive oxygen species on addition of hexavalent chromium (potassium dichromate, $K_2Cr_2O_7$ ) to lung cells in culture was studied using flow cytometer analysis. A Coulter Epics Profile flow cytometer was used to detect the formation of reactive oxygen species after $K_2Cr_2O_7$ was added to A549 cells grown to confluence. The cells were loaded with the dye, 2',7'-dichlorofluorescein diacetate, after which cellular esterases removed the acetate groups and the dye was trapped intracellularly. Reactive oxygen species oxidized the dye, with resultant fluorescence. Increased doses of Cr(VI) caused increasing fluorescence (10-fold higher than background at 200 gM). Addition of Cr(III) compounds, as the picolinate or chloride, caused no increased fluorescence. Electron paramagnetic resonance (EPR) spectroscopic studies indicated that three (as yet unidentified) spectral "signals" of the free radical type were formed on addition of 20, 50, 100 and 200 gM Cr(VI) to the A549 cells in suspension. Two other EPR 'signals" with the characteristics of Cr(V) entities were seen at field values lower than the standard free radical value. radical value.