• Title/Summary/Keyword: 작용 방향

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Experiences and Meaning of AP (Advanced Placement) at the Specialized Schools for the Highly Gifted: Through the In-depth Interview with the AP Participants (과학영재학교에서의 AP(Advanced Placement)의 경험과 의미: 대학생이 된 영재학교 졸업생들과의 심층인터뷰를 중심으로)

  • Han, Ki-Soon;Choe, Ho Seong
    • Journal of Gifted/Talented Education
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    • v.24 no.6
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    • pp.1001-1024
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    • 2014
  • The purpose of the study is to explore the experiences and meaning of the AP (Advanced Placement) at the specialized school for the highly gifted through the in-depth interview with 39 college students who had graduated from the specialized schools with the AP experiences. It is expected that the AP will be expanded to the students at the Science High Schools from the year of 2015, however, there has been no study to examine the realities of the AP in-depth especially through the voices of the AP participants. Students have taken 8 required and/or selective courses as AP in average. Students usually start to take AP from the second year of the specialized school for the highly gifted, but some start from the first year through the placement test. Numbers of available AP courses vary by subjects, but relatively more courses open in the areas of math and physics. Students' opinions regarding the AP were quite positive. Specifically, the high quality of the AP class and energetic interaction between student and teacher compared to the college classes were preferred by the students. However, it was controversial whether C+ is enough for the pass condition of the AP. Students were using the shortened time by AP in diverse ways, such as early graduation, double majors, exchange students, individual researches, and so on. Most of all, they tried to search for their career interests through the AP experiences. In closing, the present study provides some advices and future directions for the better AP management, including the improvement of administrative system between schools for the gifted and the universities, and the expansion of the number of university which approves the AP system.

Geochemistry of Granites in the Southern Gimcheon Area of Korea (김천남부에 분포하는 화강암류의 지구화학)

  • 윤현수;홍세선
    • The Journal of the Petrological Society of Korea
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    • v.12 no.1
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    • pp.16-31
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    • 2003
  • The granites in the southern Gimcheon area can be divided into two parts, marginal hornblende biotite granodiorite (Mgd) and central biotite granodiorite to granite (Cgd). Mgd and Cgd are gray in color and display gradational contact relations and are mainly composed of coarse-grained and medium-grained rocks, respectively. Mgd has more frequent and larger mafic enclaves than Cgd, and the two granites partly show parallel foliation at thire contact with gneisses. From representative samples of the granites, K-Ar biotite ages of 197∼207 Ma were obtained. Considering the blocking temperature of biotite, it is suggested that the emplacement age of the granitic magma was probably late Triassic. The anorthite contents of plagioclases in Mgd display less variation than those of Cgd, indicating that Mgd crystallized within a narrow range of temperatures. In the Al$\_$total/-Mg diagram, the biotites from the granites plot within the subalkaline field, and the smooth slope indicates differentiation from a single magma. All amphiboles from the granites belong to magnesio-hornblende. The linear trends of major oxides, AFM and Ba-Sr-Rb indicate that Mgd and Cgd were fractionally differentiated from a single granitic magma body crystallizing from the margin inwards. The relations of modal (Qz+Af) vs. Op, K$_2$O vs. Na$_2$O, Fe$_2$ $O_3$ vs. FeO, Fe$\^$+3/(Fe$\^$+3/+Fe$\^$+2/) and K/Rb vs. Rb/Sr show that they belong to I-type and magnetite-series granitic rocks developed by the progressive melting products of fixed sources. REE data, normalized to chondrite value, have trends of enriched LREE and depleted HREE together with weakly negative Eu anomalies.

Identification of Major Crude Oils Imported into Korea using Molecular and Stable Carbon Isotopic Compositions (분자지표 및 탄소안정동위원소 조성비를 이용한 국내 수입 주요 원유의 식별)

  • Kim, Eun-Sic;An, Jun-Geon;Kim, Gi-Beum;Shim, Won-Joon;Joo, Chang-Kyu;Kim, Moon-Koo
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.3
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    • pp.247-256
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    • 2012
  • Stable carbon isotope ratio of oil components are known to be unaffected by weathering processes and thus has been widely used to determine the origin of spilled oil. In this study, molecular index and composition of stable carbon isotope in 15 crude oils and petroleum product were analyzed and used as oil fingerprints to determine the discriminating power of each fingerprinting method among target crude oils. Through the fingerprints of alkane distribution only Bintulu and B-C(1%) were distinguishable from other crude oils. The pristane/phytane ratio can classify the crude oils into three groups but differentiation of crude oils within a group was impossible using the ratio. The crude oils of A.L., A.S.L., Foroozan and B-C(1%) were differentiated from the other oils using PAH source recognition indexes of C2D/C2P and C3D/C3P. The usage of 4-mD/1-mD and 2/3-mD/1-mD ratio was able to distinguish A.S.L., Bintulu and Oman from the other crude oils. However the PAH source recognition ratios in the other crude oils were similar and thus they were impractical to be used for source identification among the target crude oils. Stable carbon isotope ratios of alkanes were able to uniquely specify each crude oil in the plot of ${\delta}^{13}C_{C21}$ and ${\delta}^{13}C_{C25}$ except A.L., A.M., Qatar-Marine, B-C(1%). The oil fingerprinting method using stable carbon isotope ratios of individual alkane compounds showed more discriminating power among the target crude oils than the conventional source recognition indexes of PAHs or alkanes.

Effects of Additive materials on the Quality Characteristics of Dasik (다식의 제조시 첨가하는 부재료와 품질특성)

  • 정외숙;박금순
    • Korean journal of food and cookery science
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    • v.18 no.2
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    • pp.225-231
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    • 2002
  • This study was carried out to investigate the possibility of improving the texture and flavor of Dasik by adding various types of sugar (syrup, honey) and flavor ingredients (omija, chija, coffee, green tea extract) to rice powder. Dasik samples were prepared, and the sensory quality and physical characteristics of those were compared. The moisture content of Dasik added with syrup was higher than that of honey. Coffee Dasik with syrup was the highest (23.6) in moisture content. In sensory quality, the omija and coffee Dasik showed the highest score in flavor quality (p<.001). Omija Dasik with honey and coffee Dasik with syrup showed the highest scores in overall acceptability (6.4, 6.2). Green tea Dasik with syrup showed the highest value in the lightness (L) of color. Omija Dasik with syrup showed the highest value in the redness (a) of color Chija Dasik was the highest in the yellowness(b) of color. In physical characteristics, the hardness was negatively correlated with the moistness, tenderness, and texture acceptability in sensory quality(p〈0.001). The cohesiveness was positively correlated with the overall acceptability in sensory quality (p〈0.01). In the relation of texture characteristics and sensory quality, the higher the moisture content, the lower the hardness and springiness were, but the higher the brittleness and the cohesiveness were(p〈.001). Overall, omija and coffee Dasik appeared to have desirable flavor, taste and overall acceptability.

Consumption and Preference of Seafood, and Desires for the Seafood Utilization in School Lunch Program among Middle and High School Students in Korea (중.고등학생의 수산물 이용 음식에 대한 이용실태와 선호도 및 학교급식에서의 요구도 조사)

  • 남혜원;이민준;이영미
    • Korean journal of food and cookery science
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    • v.18 no.1
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    • pp.1-7
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    • 2002
  • A study on the seafood consumption was conducted from 1902 adolescent students (1110 boys and 792 girls) attending middle or high school to assess the attitude and degree of satisfaction for seafood being served in the school lunch program and ultimately to promote greater seafood consumption. A self-administered questionnaire was used to record the results. The results were as follows: Sixty percent of the respondents appeared to like or not to be reluctant to seafood. The main reasons for favoring seafood were its nutritious effect and taste. On the other hand, the reason for disliking seafood was due to its peculiar smell. In terms of cooking methods, the subjects preferred raw, fried, and grilled seafdod, whereas they disliked salt-fermented, seasoned and stewed dishes. The highly preferred seafood were crab, shrimp, tuna and squid. Only 6.6% of middle school students (MS) and 3.7% of high school students (HS) liked the seafood served in school lunch program, whereas the others responded 'so so'or disliked it. The reasons for disliking seafood being served in school lunch program were poor taste (14.7% of MS, 23.5% of HS), lack of freshness(6.3% of MS, 13.9% of HS) and unattractable cooking methods(3.4% of MS, 11.1% of HS). To promote seafood consumption in school lunch program, subjects anticipated the taste improvement (37.7% of MS, 48.5% of HS), use of a variety of seafood (19.8% of MS, 24.0% of HS) and cooking methods(12.6% of MS, 22.4% of HS). Above results suggested that further efforts are needed to provide preferred cooking methods and seafood items as a way of increasing seafood acceptability.

Dynamic Characteristics of Water Column Properties based on the Behavior of Water Mass and Inorganic Nutrients in the Western Pacific Seamount Area (서태평양 해저산 해역에서 수괴와 무기영양염 거동에 기초한 동적 수층환경 특성)

  • Son, Juwon;Shin, Hong-Ryeol;Mo, Ahra;Son, Seung-Kyu;Moon, Jai-Woon;Kim, Kyeong-Hong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.3
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    • pp.143-156
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    • 2015
  • In order to understand the dynamic characteristics of water column environments in the Western Pacific seamount area (approximately $150.2^{\circ}E$, $20^{\circ}N$), we investigated the water mass and the behavior of water column parameters such as dissolved oxygen, inorganic nutrients (N, P), and chlorophyll-a. Physico-chemical properties of water column were obtained by CTD system at the nine stations which were selected along the east-west and south-north direction around the seamount (OSM14-2) in October 2014. From the temperature-salinity diagram, the main water masses were separated into North Pacific Tropical Water and Thermocline Water in the surface layer, North Pacific Intermediate Water in the intermediate layer, and North Pacific Deep Water in the bottom layer, respectively. Oxygen minimum zone (OMZ, mean $O_2$ $73.26{\mu}M$), known as dysoxic condition ($O_2<90{\mu}M$), was distributed in the depth range of 700~1,200 m throughout the study area. Inorganic nutrients typified by nitrite + nitrate and phosphate showed the lowest concentration in the surface mixed layer and then gradually increased downward with representing the maximum concentration in the OMZ, with lower N:P ratio (13.7), indicating that the nitrogen is regarded as limiting factor for primary production. Vertical distribution of water column parameters along the east-west and south-north station line around the seamount showed the effect of bottom water inflowing at around 500 m deep in the western and southern region, and concentrations of water column parameters in the bottom layer (below 2,500 m deep) of the western and southern region were differently distributed comparing to those of the other side regions (eastern and northern). The value of Excess N calculated from Redfield ratio (N:P=16:1) represented the negative value throughout the study area, which indicated the nitrogen sink dominant environments, and relative higher value of Excess N observed in the bottom layer of western and southern region. These observations suggest that the topographic features of a seamount influence the circulation of bottom current and its effects play a significant role in determining the behavior of water column environmental parameters.

Current Status and Prospects of Various Methods used for Screening Probiotic Microorganisms (Probiotic 미생물 검사에 사용되는 다양한 방법들에 대한 현황과 향후 전망)

  • Kim, Dong-Hyeon;Kim, Hong-Seok;Jeong, Dana;Chon, Jung-Whan;Kim, Hyunsook;Kim, Young-Ji;Kang, Il-Byung;Lee, Soo-Kyung;Song, Kwang-Young;Park, Jin-Hyeong;Chang, Ho-Seok;Seo, Kun-Ho
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.4
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    • pp.203-216
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    • 2016
  • Probiotic microorganisms are thought to provide health benefits when consumed. In 2001, the World Health Organization defined probiotics as "live microorganisms which confer a health benefit on the host, when administered in adequate amounts." Three methods for screening potential probiotics have currently widely available. (1) In vitro assays of potential probiotics are preferred because of their simplicity and low cost. (2) The use of in vivo approaches for exploring various potential probiotics reflects the enormous diversity in biological models with various complex mechanisms. (3) Potential probiotics have been analyzed using several genetic and omics technologies to identify gene expression or protein production patterns under various conditions. However, there is no ideal procedure for selecting potential probiotics than testing cadidate strains on the target population. Hence, in this review, we provide an overview of the different methodologies used to identify new probiotic strains. Furthermore, we describe futre perspectives for the use of in vitro, in vivo and omics in probiotic research.

A Study on aircraft ownership and air business control requirement in Korea (항공운송사업자의 국적 제한에 관한 고찰)

  • Lee, Chang-Jae
    • The Korean Journal of Air & Space Law and Policy
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    • v.33 no.1
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    • pp.147-174
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    • 2018
  • The air transportation industry is a field where control and interference of the state are generalized compared to other industries. However, the premise for national intervention in the air transportation industry is the determination of the nationality of the aircraft or airline company concerned. This is because it is necessary to clarify the distinction between the domestic and foreign carriers so that they can exercise airspace sovereignty. The purpose of this paper is to compare the current status and contents of Korean law and regulations on the determination of nationality with the foreign legal system. To this end, the starting point of the discussion is to look at the history of nationality restrictions on the US air transport industry and the issues that arise in the content and operation of the system today. In addition, this paper examined the provisions of the Japanese aviation law, which is very similar to that of Korea, and then compared the current legal provisions of the United States, Japan and Korea. As a conclusion, this paper sought the direction of revision of the Korean law on the basis of the foreign status of the restriction of nationality in the air transportation industry. Compared with our law, the US and Japan are generally regarded to be more concerned with the contents of their own airline companies than those of foreigners or non-citizen. In spite of the fact that there are many laws and regulations in the United States regarding the de facto dominance of domestic airline companies by foreigners, there have been a lot of controversies in this matter. By the way, Japan has been stipulating regulations on holding companies and affiliated companies. In the global era, it would be meaningful to check the status of the nationality restrictions in the aviation industry, which is based on internationality. I hope that this study will be able to build a legal institutional basis for Korea's aviation industry development from a reasonable protectionist point of view rather than a narrow nationalism in a rapidly changing era.

Changes of Arachidonic Acid Metabolites in Silica-Exposed Alveolar Macrophage of Rats (유리규산분진에 폭로된 흰쥐의 폐포대식세포에 있어 아라키돈산 대사산물의 변화)

  • Lim, Young;Yun, Im-Goung
    • Tuberculosis and Respiratory Diseases
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    • v.39 no.4
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    • pp.304-309
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    • 1992
  • Background: The alveolar macrophage may metabolize arachidonic acid through cyclooxygenase- and lipoxygenase- catalyzed pathways to produce a variety of metabolites of arachidonic acid. The production of these metabolites of arachidonic acid may enhance the defensive ability of the challenged lung. However, continued stimulation with the consequent production of proinflammtory metabolites of arachidonic acid, may ultimately enhance the disease process by contributing to chronic bronchoconstriction, fibrosis, and the persistent release of toxic oxygen species. Silicosis is an example of a disease process resulting from chronic exposure of the lung to foreign particles. This study was carried out to evaluate the changes of arachidonic acid metabolites from macrophages in experimental silicosis. Methods: We measured $PGE_2$, and $LTB_4$ in cultured macrophages taken from rats by radioimmunoassay at 24 and 48 hours after stimulation by silica dust, natural carbon dust, lipopolysaccharide, calcium ionophore (A23187) and medium (RPMI) as a control. For the experimental silicosis, 50 mg silica in 0.5 ml saline was administered intratracheally into the rat and grown to 20 weeks and measured $PGE_2$, and $LTB_4$ in the cultured macrophages lavaged from that rat. The used stimulants were the same as above. Results: 1) The amount of $PGE_2$ in the cultred macrophages from normal rat was significantly decreased in the group which was stimulated with silica dust for 48 hours compare with control non-stimulated group. 2) In the experimental silicosis group, $PGE_2$, release in cultured macrophages after 48 hours incubation with silica and natural carbon dust tended to be lower than those of non-stimulated group. 3) There were marked changes of $LTB_4$ in the groups of normal rats which were incubated with silica for 24, 48 hours and natural carbon for 48 hours compared with non-stimulated group. 4) In the experimental silicosis group, the release of $LTB_4$ was significantly increased macrophages cultured with silica and natural carbon dust after 24 and 48 hours incubation compared with non-stimulated group. Conclusion: The results of these studies suggest that the in vitro exposure of rat alveolar macrophge to silica and coal dust results in an alteration in alveolar macrophage metabolism of arachidonic acid that may promote an inflammatory reaction in lung tissue.

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The Spin-Rotation Interaction of the Proton and the Fluorine Nucleus in the Tetrahedral Spherical Top Molecules

  • Lee, Sang-Soo;Ozier, Irving;Ramsey, N.F.
    • Nuclear Engineering and Technology
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    • v.5 no.1
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    • pp.38-43
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    • 1973
  • The spin-rotation constants of the proton and tile fluorine nucleus in C $H_4$, Si $H_4$, Ge $H_4$, C $F_4$, Si $F_4$ and Ge $F_4$ were determined experimentally by the molecular beam magnetic resonance method. From the Hamiltonian and the high field approximation, the quantized energy level is given by the following equation. W $m_{I}$ $m_{J}$=- $g_{I}$ $m_{I}$H- $g_{J}$ $m_{J}$H- $C_{av}$ $m_{I}$ $m_{J}$, where $c_{av}$ is one third of the trace of the C tensor. In the nuclear resonance experiment, the proton and the fluorine nuclear resonance curves consist of many unresolved lines given by v=- $g_{J}$H- $C_{av}$ $m_{I}$, and a Gaussian approximation is made to correlate $c_{av}$ to the experimentally obtained half-width of the resonance curve. In the rotational resonance experiment, the five resonance peaks as predicted by v=- $g_{I}$H- $c_{av}$ $m_{I}$, $m_{I}$=0, $\pm$1 and $\pm$2, were all observed. The magnitude of car was determined by measuring the frequency distance between two adjacent peaks. The sign of $c_{av}$ was determined by the side peak suppression technique. The technique is described, and the sign and magnitude of the spin-rotation constant cav are summarized as following: for C $H_4$ -10.3$\pm$0.4tHz(from the rotational resonance), for SiH +3.71$\pm$0.08kHz(from the nuclear resonance), for Ge $H_4$+3.79$\pm$0.13kHz(from the nuclear resonance), for C $F_4$, -6.81$\pm$0.08kHz(from the rotational resonance), for Si $F_4$, -2.46$\pm$0.06kHz(from the rotational resonance), and finally for Ge $F_4$-1.84$\pm$0.04kHz(from the rotational resonance).onal resonance).esonance).

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