• Journal of the Korean Ceramic Society
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• v.33 no.2
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• pp.127-134
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• 1996

The thermal residual stresses were estimated for brazed Si3N4/S.S.316 joints with Cu/Mo multi-interlayers using FEM, and their bending strengths at room temperature were measured for various interlayer configura-tions. The Cu, Mo multi-interlayer decreased the maximum residual stress in Si3N4 and caused the residual stress redistribution rsulting in the high residual stress at Mo interlayer. The stress distribution in the joints as well as the maximum residual stress in silicon nitride were found to be main factors for determining bending strengths and Weibull modulous of the joints. The bending strength of the brazed Si3N4/S.S.316 joints with specific Cu, Mo multi-interlayer system were found to be above 400 MPa.

• Journal of agriculture & life science
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• v.43 no.1
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• pp.17-23
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• 2009

This study was conducted to compare volumes estimated from two taper functions and observed volumes of Chamaecyparis obtusa trees to evaluate accuracy and precision of centroid method. Centroid volume estimates were also compared with volume estimates from existing Forest Resources Evaluation and Prediction Program. The results of this study showed that Gregoire's simple taper function produced unbiased volume estimates while the others were biased. Volume estimates from the Forest Resources Evaluation and Prediction Program were also biased when applied in the Jangseong National Forest regions. These results suggested that the centroid method could produce reliable stem volumes of trees when no other reliable stem volume equations exist.

• Korean Journal of Medicinal Crop Science
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• v.15 no.4
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• pp.261-265
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• 2007

A climatic feature, growth condition and incidence phase of disease and pest in Korean ginseng (Panax ginseng C. A. Meyer) were surveyed, both the conventional cultivation and culture in the forest located in Jinan. The results were as follows. The forest field was lower $1^{\circ}C$ in the air temperature, lower $1.9^{\circ}C$ in the soil temperature and 11.8% lower in the soil temperature compared with the conventional field. The wind velocity of the forest field was three times slower, but the dew condensation time was 3.3 hours longer than the conventional field. Particularly, the amounts of solar radiation in the forest was remarkably lower, while the rainfall was little lower with no significance. The incidence of disease and pest in the forest field was severe compared with that of the conventional field. Among them, Colletotrichum gloeosporioides, Cylindrocarpon destructans, and Alternaria panax was severe in the forest field while, Botrytis cinerea was severe in the conventional field. The growth condition of forest field in Panax ginseng C. A. Meyer was 50% worse in general and the root weight was 87.2% less than the 3-year-old ginseng in the conventional field.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.9-14
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• 1977

The productive structure and the productivity of ${\times}$Populus albaglandulosa plantations, where are middle parts of the Korean peninsula, were studied by means of stratifying clip technique and of allometry. The densities of stands in the sample areas were 693 trees/ha in 6 year-old plantation and 527 or 625 trees/ha in 9 year-old one. The photosynthetic part of the productive structure was not shown normal conical form but layering. So this was efficient to transmit solar radiation into the stand floor. The standing crop of the terrestrial parts of 6 year-old plantation was 18.11 ton/ha and that of 9 year-old one 38.8 to 47.3 ton/ha. The wood volume to trunk to 6 year-old was $31.3m^3/ha$ and that of 9 year-old was 68.8 to $83.9m^3/ha$. The annual net production of 6 year-old plantation was 4.8 ton/ha/year and that of 9 year-old one was 10.0 to 11.7 ton/ha/year and its wood volume of trunks was 17.9 to $21.1m^3/ha/year$. In the 9 year-old plantation the standing crop or the annual net production was different between two sample areas. This seemed that the cause was not due to chemical character but to physical character of soil.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.461-467
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• 2020

The aim of this study was to utilize Kozak's stem taper model to develop both a stem taper equation and a stem volume table for Criptomeria japonica, a tree species distributed across Korea. A total of 1,000 sample trees were cut and collected across the country to measure their diameters by stem height. The equation was then used to estimate examine their stem shapes. Our results show that the Fitness Index for the equation was 98.7%, the Mean Absolute Deviation (MAD) was -0.0142, and the MAD was 1.1640, thus indicating a high level of fitness. A statistically significant difference (p < 0.05) was also found from the analysis of discrepancies between a current table and the new table used in this study. It is therefore suggested that the new table-with data from actual stands-will contribute to enhancing the accuracy of national and municipal forest statistics and reducing losses caused by imprecise data on available forest resources.

• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.62-69
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• 2011

Six commonly used non-linear growth functions were fitted to individual tree height-dbh data of eight major tree species measured by the $5^{th}$ National Forest Inventory in Chungcheong province. A total of 2,681 trees were collected from permanent sample plots across Chungcheong province. The available data for each species were randomly splitted into two sets: the majority (90%) was used to estimate model parameters and the remaining data (10%) were reserved to validate the models. The performance of the models was compared and evaluated by $R^2$, RMSE, mean difference (MD), absolute mean difference (AMD) and mean difference(MD) for diameter classes. The combined data (100%) were used for final model fitting. The results showed that these six sigmoidal models were able to capture the height-diameter relationships and fit the data equally well, but produced different asymptote estimates. Sigmoidal growth models such as Chapman-Richards, Weibull functions provided the most satisfactory height predictions. The effect of model performance on stem volume estimation was also investigated. Tree volumes of different species were computed by the Forest Resources Evaluation and Prediction Program using observed range of diameter and the predicted tree total height from the six models. For trees with diameter less than 30 cm, the six height-dbh models produced very similar results for all species, while more differentiation among the models was observed for large-sized trees.

• The Journal of Korean Philosophical History
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• no.59
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• pp.39-63
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• 2018

Kiho Academic in the late Joseon Korea, the negative effect of the Horak debate is amplified and the division within the academic is accelerated. However, the scholars of the Kiho Academic field put forth efforts to unify the academics with the same sense of responsibility to end the schism. Nevertheless, the scholars of the Kiho Academic have shown various differences in the process of accepting Neo-Confucianism, which creates new schools. Therefore, Kiho Academic in the late Joseon Korea coexisted with various schools with different academy positions. Some of the representative groups are Hwaseo, Nosa, Ganjae, Yeonjae, and Uuidang Schools. In addition, through the scholarly differentiation and the school division of the Kiho Academic, the debate on the mind that characterizes Neo-Confucianism of the late Joseon Korea has developed. However, there was a common value that everyone pursued in the middle of the debate: the construction of a moral ideal society, the ultimate goal of Neo-Confucianism. In conclusion, though the purpose they pursued was not fulfilled, it can be seen from the debate on the mind that they fiercely demanded that these requests were urgent in the late Joseon Korea This paper, therefore, the situation of the Kiho academic in the late of Joseon Korea, the problem consciousness of the scholars of the Kiho academic, and the issue and development of debate on the mind.

• The Journal of Korean Philosophical History
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• no.53
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• pp.63-100
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• 2017

In this article, I researched Nam Dae-nyeon's(1887~1958) thought of Neo-confucian theories, interpretation of confucian canons, and evaluation of historical figures. First, from the side of Neo-confucian theories, he asserted that Qi(氣) had behaviors and Li(理) had not. About his teacher Jeon Wu's(田愚) theories, he thought that those were in tradition of Confucius(孔子) and Mencius(孟子), but not emphasized presidence of mind. And he criticized the theory of mind was Li(理). Second, from the side of interpretation of Confucian canons, Nam Dae-nyeon's study centered on Four Books(四書). This showed he was in tradition of Neo-confucianism. Through this studies he emphasized the importance of Confucian Ren(仁) and Filial piety(孝), self-consciousness as gentry(士). Third, from the side of evaluation of historical figures, Nam Dae-nyeon evaluated many Chinese and Korean scholars, for example, Qu Yuan(屈原), Lu Zhong-lian(魯仲連), Zhen De-xiu(眞德秀), Lu Long-qi((陸?其), Zhang Lu-xiang (張履祥) of China, and Jeong Mong-ju(鄭夢周), Zho Kwang-jo(趙光祖), Yi Hwang(李滉), Yi Yi(李珥), Jeon Wu(田愚) of Korea. And his criteria for evaluation of historical figures was fidelity and insight.

• Journal of the Korean Wood Science and Technology
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• v.16 no.2
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• pp.42-49
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• 1988

Anatomical characteristics on abnormal type of bisected compression woods and light colored wood intervened between these dark colored compression woods on under part and their respective opposite woods on upper parts of cross section in Pinus densiflora S. et Z. stem were compared through optical microscopic investigation. and the obtained results were summarized as follows: 1. Tracheid length increased linearly as the number of rings from the pith increases in all investigated parts, but increasing tendency in tracheid length was similar within bisected two compression woods and their opposite woods. 2. Tracheids were the shortest in bisected two compression woods and tracheid length in intervened wood between these two compression woods was longer than in compression woods but shorter than in the opposite woods. 3. Bisected two compression woods and intervened wood between these two compression woods revealed similar features in tracheid transition from springwood to summerwood, intercellular space, tracheid entanglement, and cross sectional view of tracheid. but spiral check was observed only in these two compression woods, therefore the intervened wood between these two compression woods disclosed anatomical characteristics similar to, not typical of, compression woods.

• Journal of Environmental Policy
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• v.13 no.1
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• pp.49-68
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• 2014

In 2012, Korea adopted RPS after having implemented FIT for 10 years since 2002. We show how the choice of policy between RPS and FIT affects firm's choice of intermediate goods between a domestic and a foreign supplier, given the presence of transaction costs, When transaction costs are not sufficiently high, RPS is found to create a favorable environment for the domestic provider, which has comparative disadvantage initially, to be able to enter the market and to catch up with the foreign provider. The result implies that the Korean government's decision to implement RPS was optimal, given Korea's comparative disadvantage in green energy relative to major developed countries.