• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.2
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• pp.97-102
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• 1999

This study was conducted to compare seasonal changes of height, diameter at root collar, biomass and chlorophyll contents of Abies holophylla seedlings grown in Sangju National University Nursery under different light intensities. Four light intensities were adopted using nylon net such as 100% sunlight(1800 $\mu$㏖ m$^{-2}$ s$^{-1}$ ), 75% of sunlight (1350 $\mu$㏖ m$^{-2}$ s$^{-1}$ ), 50% of sunlight (900 $\mu$㏖ m$^{-2}$ s$^{-1}$ ) and 25% of sunlight (450 $\mu$㏖ m$^{-2}$ s$^{-1}$ ). Planting density in four light intensities was 30 cm$\times$30 cm. In each treatment, 100 trees were planted and height, diameter at root collar, biomass and chlorophyll contents were measured. The highest height, diameter at root collar and biomass in Abies holophylla seedlings were observed at 100% full sunlight. Lowest chlorophyll contents (Chlorophyll a, b and total) were shown at 25% of sunlight, lowest light intensity treatment in this study. Growths and chlorophyll contents of Abies holophylla seedlings were strongly associated with light intensity. Photosynthesis has to be investigated in near future because photosynthesis and chlorophyll contents were strongly related to tree growth with long periods.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.137-146
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• 1996

To increase the oxidation-resistance of graphite substrate, we have tried to form SiC film on its surface by Sol-Gel method. TEOS(Tetraethyl orthosilicate) and phenol resin have been used as silicon(Si) and carbon(C) sources, respectively. In order to know the effect of the TEOS Sol concentration on the forming of SiC film, we have taken 5 different $H_2O$/TEOS mol ratios of 2, 4, 6, 8 and 10. And the coating states of SiC on the graphite substrate have been analyzed with X-ray diffractometer and scanning electron microscope (SEM), and we have obtained about 5${\mu}m$, 12${\mu}m$, 7${\mu}m$, 7${\mu}m$ and 2 ${\mu}m$ as the thickness of SiC coating layers, respectively. For also knowing the oxidation resistance the SiC coated graphites at $1600^{\circ}C$ were heated again at $1000^{\circ}C$ under air atmosphere for 1 hr, and as a result we have received the weight losses of 26.17%, 20.97%, 17.28%, 21.73% and 28.13%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1152-1157
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• 2001

Two kinds of samples were prepared from the loin in the carcass with grade B2 and D, which were chilled for 24 hour after slaughter. The fresh beef in this study were obtained by chilling the loin for 1 day after wrapping them. On the other hand, the chilled beef were obtained by cutting the loin by 500 g and chilling them for 30 day after vacuum packing. The experiment was carried out to compare the palatability related with characteristics of loin with grade B2 and D and to investigate the chilling effect of the loin with grade D. In the case of fresh beef, it was found that the loin with grade B2 has better meat color, but lower pH, lactic acid content, and myoglobin content, than them of the loin with grade D. Also, the loin with grade B2 has lower tenderness due to its low hardness and chewiness, and high myofibrillar fragmentation index (MFI). Furthermore, it has high monounsaturated fatty acid/saturated fatty acid (MUFA/SFA) and ATP content, and good raw meat aroma. It also shows an excellent palatability of cooked meat, although it has low cooking loss and heat shotening. On the other hand, the loin with grade D has higher chilling effect on hardness, chewiness, MFI and MUFA/SFA, than them of the loin with grade B2. However, in the case of chilled beef, the loin with grade D shows much worse tenderness, cooked meat aroma, and palatability than them of the loin with grade B2.

• Journal of Korean Society of Forest Science
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• v.104 no.1
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• pp.90-97
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• 2015

The objective of this study was to find optimal amount of fertilization of container seedling production for Zelkova serrata, Ulmus parvifolia, Betula costata and Tilia amurensis. To reach our goal, we measured root collar diameter (RCD), height, biomass and seedling quality index (SQI) of container seedlings of four deciduous hardwood species grown at three different fertilization treatments ($0.5g{\cdot}L^{-1}$, $1.0g{\cdot}L^{-1}$ and $2.0g{\cdot}L^{-1}$). Z. serrata seedlings grown at $2.0g{\cdot}L^{-1}$ fertilization and B. costata seedlings grown at $0.5g{\cdot}L^{-1}$ fertilization showed the highest RCD, height, biomass and SQI. The RCD and height of U. parvifolia and T. amurensis seedlings showed no significant differences by fertilization treatments. Seedlings of two species at $0.5g{\cdot}L^{-1}$ fertilization showed the lowest SQI, however, SQI at 1.0 and $2.0g{\cdot}L^{-1}$ fertilization treatments were not significantly different. Based on these results, it is appeared that container seedlings of Z. serrata at minimum $2.0g{\cdot}L^{-1}$ fertilization, U. parvifolia and T. amurensis at $1.0g{\cdot}L^{-1}$ fertilization and B. costata at maximum $0.5g{\cdot}L^{-1}$ fertilization were optimal nutrient conditions. Practice of optimal fertilization rate will make us get better quality seedlings and reduction of production costs in the container nursery system as well as good field performances with higher survival rate after planting.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2000.11a
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• pp.59-59
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• 2000

원자력발전소 1차계통과 격납용기 내부에서 사용되는 주요 부품들은 운전중에 발생한 방사 성 물질들의 침투와 홉착에 의해 오염되어 간다. 이 오염된 부품 및 장비, 공구, 방호복, 방호모자, 작업화 등의 세정과 정비를 위해서는 제염이 선행되어야 한다. 현재의 제염법은 2차 방사성 폐기물을 발생하는 문제점이 있다. 따라서I 2차 폐기물의 발생을 근원적으로 줄일 수 있는 새로운 제염방안이 절실히 요구되고 있는 실정이다. 본 논문에서는 이러한 문제점을 해결할 수 있는 제염법을 개발하기 위해 2가지 방법을 적용하였다. 첫째로, 원자력 발전소에 서 나오는 방사능 오염 세탁물 제염을 위한 액체 및 초임계 이산화탄소를 이용한 방사능 오염물 제염기를 개발하였다. 제염기는 반응기(16 liteer), 회수시스템 그리고 저장용기로 구성되어있다. 세정에 사용된 모든 이산화탄소는 회수되어 재사용 되어지므로 2차 폐기물의 발생을 근원적으로 없앨 수 있다. 제염성능실험결과 제염지수가 목표치보다는 낮았다. 이는 제염 기에 계면활성제와 기계적인 힘을 가한다면 높은 제염지수를 얻을 수 있을 것으로 예상된다. 둘째로, 발전소에서 나오는 오염된 공구나 장비의 세척을 위한 가변형 노즐 드라이 아이스 세척 장치를 개발하였다. 표면세정시 얼음층 형성방지를 위하여 열공급장치를 부착하였다. 유라표면에 지문을 묻혀 실험한 결과 쉽게 제거되었다. 실제 발전소에 있는 P Pump-housing의 표면을 실험한 결과 방사능의 약 40-80%가 제거되었다. 이 장치는 검출기, 제어장치, 용액상에서 세척될 수 없는 장치에 적용할 수 있는 효율적인 세척법이다. 이는 프리프레그의 표면처리 가 충과 충간의 접착강도를 증가시키고 또한 탄소섬유와 에폭시 간의 계면력을 증가시킨데 기인하는 것으로 사려된다.되었으며, duty-on 시간의 증가에 따라 $Cr_2N$ 상의 형성이 점점 많아져 80% duty-on 시간 경우에는 거의 CrN과 $Cr_2N$ 상이 공존하는 것으로 나타났다. 또한 duty-on 시간이 증가할수록 회절피크의 세기가 증가하여 결정화가 더 많이 진행되어짐을 알 수 있었다. 마찬가지로 바이어스 펄스이 주파수에 다른 결정성의 변화도 펄스의 주파수가 증가할수록 박막이 결정성이 좋아지고 $Cr_2N$ 상이 쉽게 형성되었다. 증착 진공도에 따른 결정성은 상대적으로 질소의 농도가 높은 낮은 진공도에서는 CrN 상이 주로 형성되었으며, 반대로 높은 진공도에서는 $Cr_2N$ 상이 많이 만들어졌다. 즉 $1.3{\times}10^{-2}Torr$의 증착 진공도에서는 CrN 상만이 보이는 반면 $9.0{\tiems}1-^{-2}Torr$ 진공도에서부터 $Cr_2N$ 상이 형성되기 시작하여 $5.0{\tiems}10^{-2}Torr$ 진공도에서는 두개의 상이 혼재되어 있음을 알 수 있었다. 박막의 내마모성을 조사한 결과 CrN 박막의 마찰 계수는 초기에 급격하게 증가한 후 0.5에서 0.6 사이의 값으로 큰 변화를 보이지 않았으며, $Cr_2N$ 박막도 비슷한 거동을 보였다.차 이, 목적의 차이, 그리고

• Journal of Korean Society of Forest Science
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• v.112 no.2
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• pp.136-144
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• 2023

This study aimed to determine the optimal fertilization level for the production of Hovenia dulcis Thunb. seedlings. The height, root collar diameter, biomass, seedling quality index, and chlorophyll content of Hovenia dulcis container seedlings (1-0) according to six fertilization treatments (control, 0.5, 1.0, 1.5, 2.0, 2.5 g·L^-1) were investigated. The height, root collar diameter, and biomass of Hovenia dulcis container seedlings increased with increasing fertilization, but there were no significant differences among the ≥1.5 g·L^-1 treatments, and the 2.5 g·L^-1 fertilization treatment was associated with significantly lower height growth. The seedling-quality index showed a high but non-significant difference in the ≥1.5 g·L^-1 treatment range, and the chlorophyll content was highest in the 1.5 g·L^-1 treatment group. Considering the environmental and cost aspects of fertilization, the appropriate level of fertilization required for superior container seedling production of Hovenia dulcis was 1.5 g·L^-1, and a minimum fertilization treatment of ≥0.5 g·L^-1 should be applied to meet the minimum seedling specifications. These results are expected to be used as basic data for establishing an efficient seedling-production system and stable supply of Hovenia dulcis, which is used as a medicinal and honey plant.

• Sim-seong Yeon-gu
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• v.38 no.1
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• pp.161-200
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• 2023

The fairy tale 'The King's Ass's Ears' is a simple story about a king and a barber. The king's 'Ass's ears' is discovered by the barber, who becomes sick due to his inability to reveal the secret. He eventually confesses the secret in a deep pit and covers it with soil, but a reed grows in that spot and reveals the secret when it sways in the wind. This fairy tale is registered in Stith Thompson's narrative type AT 782 as 'King Midas and His Ass's Ears', corresponding to a well-known story of King Gyeongmun in Korea, as it is published in elementary textbooks. When something becomes conscious, its automatic mechanical tendency leads to obsolete and rigid. To avoid rigidity in our conscious life, we need continuous renewal via contact with the flow of mental events in our unconscious. From the aspect of analytical psychology, the King's 'Ass's ears' enables irrational contact with the fundamental emotions lost in the flow of life. The barber symbolizes spiritual transformation, and the reed swaying in the wind symbolizes the revelation of secretive knowledge associated with the divine. The king can hear the sound of all creation and become one with it, which was the will of the divine. The Self, as the psychic totality of an individual and paradoxically also represents the regulating center of the collective unconscious, continually seeks to merge and transform with the lost primal layer of humanity, which has now become distant and discarded due to the development of human consciousness.

• Progress in Superconductivity and Cryogenics
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• v.25 no.2
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• pp.10-13
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• 2023

High-T_C superconductivity (HTSC) has been the central issue in the field of condensed matter physics for decades. An essential part of the research on superconductivity is finding new exotic superconductors. It was recently suggested that Ir-substituted La_0.7Sr_0.3MnO₃ (LSMIO) is a new high-T_C superconductor. However, systematic studies to experimentally verify the superconductivity have not been done. Here, we report the growth processes of LSMIO thin films and their electrical transport properties. We observed a clear negative correlation between the intensity of the laser utilized for film deposition and the Curie temperature of the deposited film. We attributed this effect to the suppression of Sr concentration in the LSMIO films as the laser intensity increased. However, our LSMIO films show conventional ferromagnetism instead of HTSC. To realize the HTSC in LSMIO systems, further exploration of diverse compositions of LSMIO compounds is essential.

• Korean Journal of Plant Resources
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• v.36 no.2
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• pp.172-180
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• 2023

In the current study, four groups; control, 500, 1000, and 2000 mg/L, were treated to investigate the effects of physiological and growth characteristics on Machilus thunbergii under various fertilization levels. As a result of the physiological response to the fertilization treatment, the fertilized group demonstrated relatively higher levels of A, ITE, WUEi, V_camx, PI_abs, and SFI_abs in comparison to the control. The best photosynthetic mechanism was most clearly seen at 1000 mg/L, which involved gas exchange through active stomatal opening and closing. For a productive photosynthetic mechanism. As seen in the growth response of M. thunbergii to fertilization treatment, the fertilized group has significantly higher height, DRC, leaf dry weight, stem dry weight, total dry weight, LWR, and SWR than the control group. A healthy seedling quality index was particularly evident at 1000 mg/L, and other growth indicators were also at a decent level. 500 mg /L also demonstrated growth characteristics that were comparable to those at 1000 mg/L. As a result, M. thunbergii featured the best physiological and growth characteristics in response to the fertilization treatment at 1000 mg/L, and 500 mg/L also showed a similar trend, which is considered to be a good option from an economical perspective.

• Journal of The Korean Association For Science Education
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• v.24 no.6
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• pp.1158-1172
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• 2004

This study searched secondary school students' epistemological views and ontological views about nature and the root causes of such their views. The subjects were 156 secondary school students and data were gathered by the questionnaire developed based on preceding researches. As a result, many secondary school students had epistemological views of unknowable nature. There were various root causes of their epistemological views such as regularity and harmony of nature, predictable and circular natural phenomenon, causation, the relation between human and nature. On the other hand, a lot of secondary school students had ontological view of supernatural nature. Their religious beliefs were very powerful influence their supernatural ontological views. The nature is the object of science and the physical world. Because those views supply science educators basic backgrounds how leaners understand science class, secondary school students' epistemological views and ontological views are precious information. From now on, it is necessary to study relations between students' epistemological views and ontological views and their science class processes.