• 구강회복응용과학지
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• 제33권1호
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• pp.55-62
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• 2017

무치악 환자를 수복할 때 임플란트 피개의치를 이용한 치료법은 전통적인 총의치의 문제점인 저작시 동통, 의치의 부족한 유지와 안정을 포함하는 기능저하 문제 등을 해결할 수 있는 방법이다. $Locator^{(R)}$ (Zest Anchors LLC, Espandido, USA) 어태치먼트는 임플란트 피개의치에 사용되는 어태치먼트 중 수직적으로 필요한 공간이 가장 적고, 나일론 부품에 따라 유지력 조절이 용이하다. 하지만 Ball이나 Bar에 비해 기능시 부품의 마모로 유지력이 빠르게 감소하는 특징이 있어 가급적 임플란트 간 각도가 최소가 되도록 식립하려는 노력이 필요하다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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• pp.35-39
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• 2000

$ZnIn_2S_4$ and $ZnGaInS_4:Er^{3+}$ single crystals crystallized in the rhombohedral (hexagonal) space group $C_{3v}^5(R3m)$, with lattice constants $a=3.852{\AA},\;c=37.215{\AA}$ for $ZnIn_2S_4$, and $a=3.823{\AA}$, and $c=35.975{\AA}$ for $ZnIn_2S_4:Er^{3+}$. The optical absorption measured near the fundamental band edge showed that the optical energy band structure of there compounds had a direct and indirect band gap, the direct and indirect energy gaps are found to be 2.778 and 2.682 eV for $ZnIn_2S_4$, and 2.725 and 2.651eV for $ZnIn_2S_4:Er^{3+}$ at 293 K. The photoluminescence spectra of $ZnIn_2S_4:Er^{3+}$ measured in the wavelength ranges of $500nm{\sim}900nm$ at 10 K. Eight sharp emission peaks due to $Er^{3+}$ ion are observed in the regions of $549.5{\sim}550.0nm,\;661.3{\sim}676.5nm$, and $811.1{\sim}834.1nm$, and $1528.2{\sim}1556.0nm$ in $CdGaInS_4:Er^{3+}$ single crystal. These PL peaks were attributed to the radiative transitions between the split electron energy levels of the $Er^{3+}$ ions occupied at $C_{2v}$, symmetry of the $ZnIn_2S_4$ single crystals host lattice.

• 농촌지도와개발
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• 제7권1호
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• pp.75-100
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• 2000

In the 21th century, many people predict the change of agricultural conditions in our country because of the arrival of knowledge- information age. Now it is supposed that agricultural technology comes to $45%{\sim}50%$ level compare to advanced countries. So the development of new technology in agriculture are demanded all the more. Agriculture in the 21th century will be grown based on the connection of environment, knowledge and taffeta. The agricultural conditions in Kyongbuk has more profitablity and potentiality, because there are wide lands, distinguished 4 seasons, various main production crops and cultural inheritance etc. For the innovation of agricultural technology in Kyungbuk, province this plan presented 7 visions; such as foods-life, knowledge-brain, precisious environment, resouces-saving, export-market, traditional- specialization and development-participation agriculture and 7 basic strategies; such as environment-stabilization, speciality-discrimination, standard-modeliztion, demand-market, field-practicality, management-information, specialization-cooperation strategy. The major contents of this plan were presented to achieve strengthen -ment and advancement of competitive power on the agriculture of Kyongbuk; 21 superme technologies get to develop the highest technique, 21 major conventional projects will be mown continuously, 21 main clops snakes to intensify competitive power. Wheras, we will be propulsed 21 special projects for increasing a phase of Kyongbuk R D. A. and we inculuded 74 items of Si-Gym region for balanced development of area This plan consisted of 1,730 items in 84 fields and about 260 billion won will be invest every year. When it is finished successfully in 10 years, agricultural technical level of Kyungbuk will be not only promote to $80{\sim}90%$ level to advanced country, but also clanged to competitive industry, and farming villiages might be changed to a space of comfortable life.

• 한국가스학회지
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• 제16권1호
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• pp.8-14
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• 2012

수소는 온실가스 배출을 저감하기 위한 미래 에너지로 고려되고 있지만, 폭발위험에 대한 문제점을 지니고 있다. 따라서 수소가 미래 에너지로 사용되기 위해서는 폭발위험에 대한 연구가 충분히 이루어져야 한다. 폭발위험은 폭발충격에 대한 이해 즉, 폭발과정에서 압력 상승속도에 대한 분석과 밀접한 관계가 있다. 본 연구에서는 폭발에 영향을 미치는 변수, 즉 연소 전후의 비열비, 화학평형상태에서 최대폭발압력, 그리고 연소속도, 이들 변수가 압력 상승속도에 미치는 영향을 살펴보았다. 화학평형상태에서 최대폭발압력과 연소속도는 압력 상승곡선에 큰 영향을 미치는 것을 알 수 있었고, 미연소 가스의 비열비는 초기압력 상승속도보다 최종압력 상승속도에 더욱 영향을 미치고, 연소가스의 비열비는 반대로 초기압력 상승속도에 더욱 큰 영향을 미치는 것을 알 수 있었다. 연소속도는 실험 데이터로부터 구하였으며 밀폐공간에서 수소가스 폭발에서는 폭연에서 폭굉으로 전이가 일어나기에는 연소속도가 매우 느림을 알 수 있었다.

• 한국수산과학회지
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• 제39권spc1호
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• pp.165-179
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• 2006

Food habits of the gavelin goby Acanthogobius hasta and the fine spot goby Chaeturichtys stigmatias populations were investigated in the Jangbong tidal flat near Incheon, Korea. Samples were taken monthly from November 1999 to January 2001. The gut contents of 248 gavelin gobies and 139 fine spot gobies were analyzed. The diet of the gavelin goby was dominated by the gammaridean amphipod Chitinomandibulum emargicoxa, the crabs Macrophthalmus japonicus and Ilyoplax pingi, the shrimp Exopalaemon carinicauda, the bivalve Raetellops pulchella and the macro-algae Porphyra tenera. On the other hand, the fine spot goby mainly feed on the shrimps Crangon affinis, Latreutes mucronatus, E. carinicauda and Alpheus japonicus, the gammaridean amphipods C. emargicoxa and Synchelidium miraculum, and the bivalve R. pulchella. A comparison between frequencies of occurrence and abundance of food items in the gut showed that crustaceans (gammaridean amphipods, crabs and shrimps) and bivalves were important foods for the two gobies. However, the main components of the gut contents were different between two species, though this was probably due to differences in spatial distribution patterns of gobies and their prey items. In conclusion, both the gavelin goby and the fine spot goby, despite being the related species and co-inhabiting the similar part of the tidal flat, had quite distinct food habits and low dietary overlap (Schoener's index: 0.4). These indicated that the two gobies are or were partitioning resources in space and time for maximum uitilization of available food.

• 한국자동차공학회논문집
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• 제20권5호
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• pp.71-80
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• 2012

To improve the $NO_X$ conversion over a SCR (selective catalytic reduction) catalyst, the DOC (diesel oxidation catalyst) is usually placed upstream of the SCR catalyst to enhance the fast SCR reaction ($4NH_3+2NO+2NO_2{\rightarrow}4N_2+6H_2O$) using equimolar amounts of NO and $NO_2$. Here, a ratio of $NO_2/NO_X$ above 50% should be avoided, because the reaction with $NO_2$ only ($4NH_3+4NO+O_2{\rightarrow}4N_2+6H_2O$) is slower than the standard SCR reaction ($4NH_3+4NO+O_2{\rightarrow}4N_2+6H_2O$). In order to accurately predict the performance characteristics of SCR catalysts, it is therefore desired to develop a more simple and reliable mathematical and kinetic models on the oxidation kinetics of nitric oxide over a DOC. In the present work, the prediction accuracy and limit of three different chemical reaction kinetics models are presented to describe the chemicophysical characteristics and conversion performance of DOCs. Steady-state experiments with DOCs mounted on a light-duty four-cylinder 2.0-L turbocharged diesel engine then are performed, using an engine-dynamometer system to calibrate the kinetic parameters such as activation energies and preexponential factors of heterogeneous reactions. The reaction kinetics for NO oxidation over Pt-based catalysts is determined in conjunction with a transient one-dimensional (1D) heterogeneous plug flow reactor (PFR) model with diesel exhaust gas temperatures in the range of 115~$525^{\circ}C$ and space velocities in the range of $(0.4{\sim}6.5){\times}10^5\;h^{-1}$.

• 한국식생활문화학회지
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• 제28권1호
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• pp.31-40
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• 2013

The purpose of this study is to analyze external elements of 'time series table serving' and to discover any problems in the table setting. We selected two traditional Korean restaurants in five-star hotels and two representative traditional Korean style restaurants and analyzed the tableware arrangement of their table settings. The results are as follows. In restaurant A, the arrangement of different styles of tableware made from a variety of materials seemed relatively natural. However, the dessert plates were 'Buncheong' ware made with 'Bakji' method; in this case, the pattern was larger than the size of the fruits served and made the food inconspicuous. Rather than using plates made with a 'bakji' method, using plates with small patterns in the 'johwa' method would complement the food. In restaurant B, the space between the tableware, spoon and chopsticks was narrow, and the spoon and chopsticks sets would not fit on the table pads when large dishes or multiple dishes were served. In this case, changing the dishes to smaller sized dishes, considering the size of the table pad, or not using the pad at all would solve the issue. In restaurant C, too many small dishes were laid on the table, making it look disorderly. We believe that recovering tableware that is no longer in use, laying dishes and cutlery inside of the table pads or not using the table pad would be better. In restaurant D, the same style and color of dishes were provided 9 times. The lack of variety could be tedious to customers. The forms and colors of dishes should be changed in accordance with the order of the meal served. However, when using tableware created by different methods such as 'Buncheong' ware or white porcelain, the same pattern should be chosen in order to elevate the dignity of the table menu through uniformity. These issues in tableware arrangement indicate that external forms of banquet table setup should be studied so that the culture of Korean traditional cuisine can be enriched.

• 한국균학회지
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• 제40권4호
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• pp.254-257
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• 2012

경기도 지방의 된장 시료로부터 악취감소 효과 미생물 중에서 효모가 분리되었으며 rDNA염기서열분석에 의하여 Pichia farinosa로 동정 되었다. 공시균주 P. farinosa NASS-2로 대량배양조건 확립 및 미생물처리제를 제조하였다. 분리한 효모로 제조한 악취저감효과 처리제의 실내 시험결과 돈분에 미생물제를 처리하고 15일 경과 후 악취가스 감소율을 조사한 결과, 암모니아가스($NH_3$ gas)는 처리 전 19.49 ppm에서 처리 후는 1.38 ppm으로, 황화수소가스($H_2S$ gas)는 처리 전 5.89 ppb에서 처리 후는 0.32 ppb으로 감소하는 효과를 나타내었다. 일반적으로 박테리아가 악취저감효과 미생물로 사용되고 있으나 본 연구에서 사용한 된장에서 분리한 효모 특히 산막효모인 P. farinosa NASS-2의 악취효과(암모니아가스, 황화수소 가스)는 처음 보고이다.

• 천문학회지
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• 제45권2호
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• pp.39-48
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• 2012

We investigate non-LTE effects on the $H_3^+$ level populations to help the analysis of the observed 2 and 3.5 micron $H_3^+$ emissions from the Jovian ionosphere. We begin by constructing a simple three-level model, in order to compute the intensity ratio of the R(3,4) line in the hot band to the Q(1,0) line in the fundamental band, which have been observed in the Jovian auroral regions. We find that non-LTE effects produce only small changes in the intensity ratios for ambient $H_2$ densities less than or equal to $5{\times}10^{11}cm^{-3}$. We then construct two comprehensive models by including all the collisional and radiative transitions between pairs of more than a thousand known $H_3^+$ rovibrational levels with energies less than 10000 $cm^{-1}$. By employing these models, we find that the intensity ratios of the lines in the hot and fundamental bands are affected greatly by non-LTE effects, but the details depend sensitively on the number of collisional and radiative transitions included in the models. Non-LTE effects on the rovibrational population become evident at about the same ambient $H_2$ densities in the comprehensive models as in the three-level model. However, the models show that rotational temperatures derived from the intensities of rotational lines in the ${\nu}_2$ and $2{\nu}_2$ bands may differ significantly from the ambie temperatures in the non-LTE regime. We find that significant non-LTE effects appear near and above the $H_3^+$ peak, and that the kinetic temperatures in the Jovian thermospheric temperatures derived from the observed line ratios in the 2 and 3.5 micron $H_3^+$ emissions are highly model dependent.

• 천문학회보
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• 제39권1호
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• pp.66.2-66.2
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• 2014

We carried out photometric observations of Maria family asteroids during 134 nights spanning from July 2008 to May 2013, and derived synodic rotational periods for 51 objects including obtained periods of 34 asteroids for the first time. In this study, we found that there is a significant excess of fast and slow rotators. The one-sample Kolmogorov-Smirnov test confirms that the spin rate distribution is not consistent with the Maxwellian at a 92% confidence level. From the correlations between rotational period, amplitude of lightcurve, and size, we conclude that rotational properties of Maria family have been changed considerably by the non-gravitational force such as the Yarkovsky and the YORP effect. Using the lightcurve inversion method, we successfully determined the pole orientation for the 13 Maria members, and found the excess of prograde objects versus retrograde with a ratio ($N_p/N_r$) of 3. This implies that retrograde rotators could have been ejected by the 3:1 resonance to the inner Solar System since the generation of Maria family. We estimate that approximately 37 - 75 kilometer-sized Maria asteroids have entered to near-Earth space every 100 Myr.