• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.146-155
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• 1992

The natural mixed stand in Jindong-Ri, according to a recent study, showed the possibility of selection cutting as a silvicultural system based on the stand structure such as DBH distribution and height distribution. However, volume structure per DBH class of this stand had not a mature stand of selection cutting. In this study, wherefore, the rate of increment for DBH and volume was used to predict the future stand structure including volume distribution per DBH class. The possibility of selection cutting was then discussed using the future stand structure. From the prediction of future stand structure for 30 years per every 10 years, it could be concluded that the stand will be induced to selection cutting forest because of enough number of trees in objective DBH class and above, total volume per hectare, and the volume of large DBH class which can be harvested every year. However, this stand still did not show the structure of typical selection cutting which has the rate of 1 : 2 : 7 in the number of trees per hectare and the volume rate of 5 : 3 : 2 for large, medium, and small DBH class. This problem could be improved by appropriate silvicultural treatments.

• Journal of Korean Society of Forest Science
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• v.81 no.1
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• pp.21-29
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• 1992

This study was conducted to provide basic information for deciding silvicultural system appropriate to a natural mixed stand in Jindong-Ri. For this, the stand structure such as DBH distribution, height distribution, and volume per DBH class were analyzed and the possibility of selection cutting as a silvicultural system was discussed. The DBH structure of the stand has reverse J-shaped diameter distribution which is typical in a selection cutting stand. The possibility of selection cutting is also accepted in the height structure by showing multi-storied height distribution of the stand. On the other hand, volume structure per DBH class did not show the mature stand of selection cutting due mainly to the lack of number of trees at 30cm DBH class and above. It seems that the unclear part of stand structure should be solved by further studies. Also, the rate of increment for DBH and volume should be estimated to predict the future stand structure.

• Journal of Korean Society of Forest Science
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• v.96 no.5
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• pp.572-579
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• 2007

Tree species diversity is an important aspect of forest ecosystem stability. Tree species inventories at defined sites and in minimum diameter classes give a reliable indicator of the diversity level as well as the structural stability level of a study site. This study was conducted to investigate the species composition and the stand structure of the natural forest, timber-harvested forest (logged-over forest) and degraded forest of the Oak-twin Township in the Bago Yoma Region of Myanmar. Natural forest showed the highest family and species richness in all the investigated forests. At the family level, Verbenaceae occupied the highest importance value index (IVI) in all the forest stands while teak (Tectona grandis Linn. f.) occupied the highest IVI at the species level. However, the small diameter classes of T. grandis and other commercial species were less than those of big diameter classes in all the investigated forests. This abnormal pattern of diameter distribution could be a problem for the sustainable production of commercial timber species in the near future.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.531-537
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• 2006

We assessed the species composition and structure of the three representative forest stands(Pinus densiflora stand, Quercus variabilis stand, and Ouercus mongolica stand), dominated in the National Long-Term Ecological Research Sites of Mt. Worak, Korea and established a benchmark series of permanent plots and transects with which future changes in forest composition and structure could be monitored. Species richness of Q. mongolica stand was greater than other two stands, due in large part to the greater habitat heterogeneity. Number of trees and species are decreased with increasing DBH classes. The successional trends of the three study stands would be mostly changed as Q. mongolica forest, regardless of forest types. Mean density ratio between alive trees and dead trees of three forest stands appeared with Q. mongolica stand 75:25, Q. variabilis stand 94:6, and P. densiflora stand 86:14, Q. mongolica stand appeared most highly from in three stands. This may be due to interspecific or intraspecific competition that it follows in various successesional stages. One side, when it saw the tree status which shows the tree health, the three forest stands all standing alive type (AS) appeared most highly with 75% to 85% and fallen dead type (DF) did not appear entirely. Remeasurement of permanent plots at periodic intervals will provide useful information on the dynamics of the forest vegetation that can be used in the development of adaptive conservation plans.

• Journal of Ecology and Environment
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• v.33 no.1
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• pp.67-77
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• 2010

Stand structure and spatial associations of the dominant tree species in Quercus mongolica stands were investigated to understand interspecific relationships and the persistent dominance of Q. mongolica. We examined the species composition, DBH (diameter at breast height) distribution, and spatial distribution of trees (${\geq}\;2.5\;cm$ DBH) in two permanent $100\;m\;{\times}\;100\;m$ plots in Q. mongolica-dominant stands on the western part of Mt. Jiri. Ripley's K-function was used to characterize the spatial patterns and associations of dominant tree species. Q. mongolica showed a continuous and reverse-J shaped DBH distribution with clumped spatial distribution in both study sites. Q. mongolica and Abies koreana exhibited a negative association implying potential interspecific competition. The positive spatial association between Q. mongolica and Alnus hirsuta var. sibirica and Fraxinus sieboldiana were affected by site characteristics: limited habitat conditions with a large proportion of rock surface. Our results suggest that interactions among species were complex and ranged from positive to negative. Differences in stand and site characteristics and regeneration mechanisms among the species play an important role in regulating their spatial distribution patterns, while competition between individuals also contributes to spatial patterning of these communities. The high density and the early developmental stage of spatial distribution and structural characteristics of Q. mongolica and the relatively low importance values of other species in the stands imply that Q. mongolica will remain dominant in the study sites in the near future.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.91-102
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• 1985

Growth and biomass production of natural stands of Quercus variabilis in relation to tree density were studied to obtain basic guide lines for future tending operation. Two natural stands of Quercus variabilis located at 900m (A stand: 6,600trees/ha, $15.84m^2/ha$, $\frac{19}{17-20}$) and 800m (B stand: 4,300trees/ha, $16.65m^2/ha$, $\frac{20}{17-21}$) elevation in Sancheong, Kyongnam Province were selected for the comparative study and following results were obtained through a sample plot method. After diameter of individual trees in the sample plots was measured, twelve average trees from each diameter class were cut felled to measure dry weight of $W_S$, $W_B$, $W_L$, $W_{Ba}$, and standing biomass and biomass production rates by a allometrior regressions related to $D^2H$. Vertical distribution of leaves along the stems indicated that photosynthesis was carried out 2.2m above the ground in Stand A and 1.2m in Stand B. Maximum photosynthesis was located 4.2m and 6.2m above the ground in Stand A and B, respectively. Leaf area index was 4.25ha/ha for Stand A, and 3.89ha/ha for Stand B. Above-ground standing biomass was 49.51 ton/ha for Stand A and 59.20 ton/ha and net annual production was 6.75 ton/ha/yr. for Stand A and 8.99 ton/ha/yr. for Stand B. The ratio of net annual production to standing biomass was 17.5% for Stand A and 16.7% for Stand B. Net assimilation rate was 2.75kg/kg/yr. for Stand A and 3.58kg/kg/yr. for Stand B. Stem wood production rate was 1.46kg/kg/yr. for Stand A and 2.09kg/kg/yr. for Stand B. Bark production rate was 0.60 kg/kg/yr. for Stand A and 0.34kg/kg/yr. for Stand B. Above data indicated that Stand B utilized growing spaces and sites more efficiently than Stand A. It is concluded chat productivity of natural stands of Quercus variabilis can be enhanced through optimization of basal areas and number of tree per hectare and that sound management of natural oak stands should be based on systematic sampling of the area for periodic productivity estimation.

• Archives of design research
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• v.17 no.4
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• pp.89-96
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• 2004

The public has only a superficial understanding of the computer games, in spite of it's psychological effects and social results. Therefore, in this study, one finds out the serious approach which leads the computer games to recognize its future in terms of new media. Stand-point from Freud to french post-structuralist, it helps the introduction to understand the computer games as a kind of contents in which we are able to observe psychological process. As a result, there are studies about the structure of the dream, the desire, and the language which allow to mention 'parmakon' ; 'difference' between self and object, it provokes the psychological dynamism and so on, the playing the game remains a real trace and change, at the level not only of our psyche but also of our body.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.292-308
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• 1992

Recently agricultural situations are being placed in unfavourable socio-economic environment as followed by rapid decrease of rural population, poor labor quality and high wages of rural society due to high speedy industrialization of social structure in Korea. In addition to those circumstances, under the UR system to be expected in the early future, free trade of agricultural products will be faced inevitably in Korea. Practically prices of rice as a principle food in this country are expensive about three times compared to those of foreign rice markets, and so how to increase the international competitiveness and food supplies are important problems to be solved rapidly. Accordingly an urgent goal is reduction of agricultural production cost by the improvement of labour productivity as a labour saving and cost down cultivation methods as the direct seeding cultivation in rice. But there are many problems in the direct seeded rice cultivation. The important things to be improved in that cultivation are development of rice varieties with lodging tolerance, effective seedling stand, weed control, irrigation management and fertilizing and so on. Moreover agricultural basis as irrigation facilities, land consolidation and farm machineries must be improved for the stability of rice cultivation in the future.

• International Journal of High-Rise Buildings
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• v.9 no.3
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• pp.273-282
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• 2020

An innovative high-rise timber-concrete hybrid structure was proposed in previous research, which is composed of the concrete frame-tube structure and the prefabricated timber modules as main structure and substructures, respectively. Considering that the timber substructures are built on the concrete floors at a different height, the floor response spectrum is more effective in estimating the seismic response of substructures. In this paper, the floor response spectra of the hybrid structure with different structural parameters were calculated using dynamic time-history analysis. Firstly, one simplified model that can well predict the seismic response of the hybrid structure was proposed and validated. Then the construction site, the mass ratio and the frequency ratio of the main-sub structure, and the damping ratio of the substructures were discussed. The results demonstrate that the peaks of the floor response spectra usually occur near the vibration periods of the whole structure, among which the first two peaks stand out; In most cases, the acceleration amplification effect on substructures tends to be more evident when the construction site is farther from the fault rupture; On the other hand, the acceleration response of substructures can be effectively reduced with an appropriate increase in the mass ratio of the main-sub structure and the damping ratio of the substructures; However, the frequency ratio of the main-sub structure has no discernible effect on the floor response spectra. This study investigates the characteristics of the floor response spectrum of the novel timber-concrete structure, which supports the future applications of such hybrid structure in high-rise buildings.

• Korean Institute of Interior Design Journal
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• no.41
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• pp.266-274
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• 2003

Synectics is one of several techniques used to enhance brainstorming by taking a more active role and introducing metaphor and structure into the process. It is unclear at what level of specificity this should be formulated as a pattern. This thesis reviews recent computational as well as experimental work on analogical reasoning based on synectics. New results regarding information processing of analogical reasoning stages, major computational models and recent attempts to compare these models are reviewed. Computational models are also discussed in the computational as well as cognitive psychology perspectives. Future directions in analogical reasoning research are proposed. The following import is the need to accommodate the typology and normal assessment in the concrete circumstances where actual reasoning and problem solving take place. In order to get to this end, we used computational models by Thagard who take the stand of ‘Computational Philosophy of Science’, which assumes ‘Weak AI’ to explicate what constitute the very pecularity of Analogical Reasoning.