• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.2
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• pp.91-101
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• 2016

This study is the compared seismic performance that are difference between the performance of structures on various site classes and beam-column connection. this analysis model was designed the previous earthquake load. To compare the performance levels of the structure was subjected to nonlinear static and nonlinear dynamic analysis. Nonlinear analysis was used to The Perform 3D program. Nonlinear static analysis was compared with the performance point and Nonlinear dynamic analysis was compared the drift ratio(%). Analysis results, the soft site class of the displacement was more increase than rock site classes of the displacement. Also The smaller the displacement was increased beam-column connection stiffness.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.4
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• pp.245-256
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• 2016

In the companion paper (I - Database and Site Response Analyses), site-specific response analyses were performed at more than 300 domestic sites. In this study, a new site classification system and design response spectra are proposed using results of the site-specific response analyses. Depth to bedrock (H) and average shear wave velocity of soil above the bedrock ($V_{S,Soil}$) were adopted as parameters to classify the sites into sub-categories because these two factors mostly affect site amplification, especially for shallow bedrock region. The 20 m of depth to bedrock was selected as the initial parameter for site classification based on the trend of site coefficients obtained from the site-specific response analyses. The sites having less than 20 m of depth to bedrock (H1 sites) are sub-divided into two site classes using 260 m/s of $V_{S,Soil}$ while the sites having greater than 20 m of depth to bedrock (H2 sites) are sub-divided into two site classes at $V_{S,Soil}$ equal to 180 m/s. The integration interval of 0.4 ~ 1.5 sec period range was adopted to calculate the long-period site coefficients ($F_v$) for reflecting the amplification characteristics of Korean geological condition. In addition, the frequency distribution of depth to bedrock reported for Korean sites was also considered in calculating the site coefficients for H2 sites to incorporate sites having greater than 30 m of depth to bedrock. The relationships between the site coefficients and rock shaking intensity were proposed and then subsequently compared with the site coefficients of similar site classes suggested in other codes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1C
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• pp.63-74
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• 2008

Site response analyses were performed based on equivalent linear technique using the local geologic and dynamic site characteristics, which include soil profiles, shear wave velocity profiles and depth to bedrock for 125 sites collected in Korean Peninsula. From the results of site response analyses, 2-parameters site classification system based on the combination of mean shear wave velocity of soil and depth to bedrock was newly recommended for regions of shallow bedrock depth in Korea. First, as the borders of bedrock depth (H) for site classification were determined as 10m and 20m, the soil sites were divided into 3 classes as $H_1$, $H_2$ and $H_3$ sites. And then, the 3 site classes were subdivided into 7 classes based on the mean shear wave velocity of soil ($V_{s,soil}$). The feasibility of new site classification system was verified and the representative site coefficients ($F_a$ and $F_v$) and design response spectrum were suggested by analyzing uniform trend and dispersion of site coefficients for each site class. The suggested site coefficients and the regression curves present the nonlinear characteristics of soils according to the change of rock outcrop acceleration with uniform trend effectively. From the comparison between the mean values of response spectrum which was acquired from the site response analysis and the suggested design response spectrum, there was a little difference in some of site classes and it was verified to adjust the integration interval to make it more suitable for the site condition in Korea.

• Journal of Plant Biology
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• v.9 no.1_2
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• pp.7-16
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• 1966

In order to determine the factors related to site quality, 13 areas of Larch growing in the Kwangung and its vicinity forest as sample plots, were examined. Sample plots included various site classes as well as age classes. Three were divided into two groups (major and minor trees). Average height of dominant trees was determined through messurement of 5 to 6 dominant tree in each sample plots. Average height of dominant 30 year-old trees was the basis for site index. A Standard Yield Table for the larch produced in Kwangnung forest was made by various data, which included age class 5, ranging from 10 to 45 years. The relationship of the height of the trees, the site conditions, and ground vegetation are investigated in this paper. The site indexes of 40 forest class age in 28-B and 28-G forest classes of the larch associations for ground vegetation had comparatively rarge differences due to the sampled areas. The relation of the direction of forest communities to the height and the diameter of the tree shwoed that its communiteis of northest and northwest parts appeared higher valueof the height and the diameter. The diameter and the height of trees were closely realted to each other. The samller the occupied area per tree and the smaller the average distance among trees, the more density was increased. The larger the density was the lower height of the trees. In the ground vegetation of the larch communities, there seems to be a definite correlation between the height of trees and the occupied area per tree or the average distance among the trees. The height of trees and site index of two larch communities were as follow: 28-B forest class site index 20.8, height 24.0m, 28-G forest class site index 18.4, height 20.9m. The ground layer was analyzed by the method of Quadrat(20/20sq. cm) with an interval of 1M. It set up 40 Quadrats of the larch communiteis. The community structure of the ground vegetation of two larch was analyzed, and important value was calculated and then evaluated. The ground vegetation under the larch had developed Burmannii Beauv stratal society below the 28-B and 28-G the forest class. Accordingly, the first important value of Burmannii Beauv was found in two ground vegetation below the larch. Therefore, this species could be quantitatively considered as the forest indicator species. Common species of each community appeared 18 species out of 34 species in the ground vegetation under two larch communities. The ground vegetation of the 28-B forest class showed more than that of the 28-G forest class. the similarity of the ground vegetation was measrued by the Frequency Index Community Coefficient. The differences between the associations were lcearly manifested by the ground vegetation tested by Gleason's Frequency Index of Community Coefficient for the analysis of each stratal society of all associations. According to F.I.C.C. the ground vegetation under two larch(28-B and 28-G) forest classes showed higher value. An investigation into the relationship of physical and chemical properties of soil and site was considered the next step to be taken in the study of the larch site classification.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.144-152
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• 2010

This study was conducted to analyze the growth characteristics and aboveground carbon storage for old growth Zelkova serrata artificial forests (site1: age class IX, site2: age class VIII) in Gwangneung Experimental Forest. The trees were classified by crown classes for analyzing forest stand structure. The growth characteristics were analized through ringwidth increment by crown classes and stem analysis of dominant trees. There were a wide range of DBH (site1: 8~62 cm, site2: 14~40 cm) and height (site1: 8~26 m, site2: 12~26 m) distributions and revealed different growth characteristics by crown classes in both sites. The mean annual increment (MAI) of ringwidth for the last 5 years of dominant trees for site1 (3.3 mm) was higher than MAI of ringwidth of total growth period (2.3 mm) and MAI of ringwidth for the last 5 years of dominant trees for site2 (2.2 mm) was equal to MAI of ringwidth of total growth period (2.2 mm). Also, the growth increment of ringwidth by crown classes had significant differences between dominant tree and the others crown classes (p<0.01) in both sites. As a results of stem analysis of dominant trees in both sites, there were similar to their volume between site1 (1.106 $m^3$) and site2 (1.035 $m^3$). In spite of old age, the annual increment of volume has been increasing steadily until recent year. Meanwhile, total aboveground carbon storage of site1 (65.6 Mg C $ha^{-1}$) was higher than that of site2 (56.1 Mg C $ha^{-1}$). The proportion of dominant and co-dominant trees to total aboveground carbon storage was more than 90% and the greatest individual aboveground carbon storage by crown classes was dominant tree in all both sites. However, individual aboveground carbon storage of dominant tree in site1 had 0.054 Mg C $tree^{-1}$ more than site2 owing to the differences from average DBH of dominant trees by sites. We think that these results will contribute to the forest practice for Zelkova serrata artificial forests as a basic information.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2006.03a
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• pp.327-336
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• 2006

Site coefficients in IBC and KBC codes have some limits to predict the rational seismic responses of a structure, because they consider only the effect of the soil amplification without the effects of the structure-soil interaction. In this study, upper and lower limits of site coefficients are estimated through the pseudo 3-D elastic seismic response analyses of structures built on linear or nonlinear soil layers considering the structure-soil interaction effects. Soil characteristics of site classes of A, B, and C were assumed to be linear, and those of site classes of D and E were done to be nonlinear and the Ramberg-Osgood model was used to evaluate shear modulus and damping ratio of a soil layer depending on the shear wave velocity of a soil layer. Seismic analyses were performed with 12 weak or moderate earthquake records, scaled the peak acceleration to 0.1g or 0.2g and deconvoluted as earthquake records at the bedrock 30m beneath the outcrop. With the study results of the elastic seismic response analyses of structures, new standard response spectrum and upper and lower limits of the site coefficients of Fa and Fv at the short period range and the period of 1 second are suggested Including the structure-soil interaction effects.

• Journal of the Korean Geotechnical Society
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• v.25 no.10
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• pp.87-97
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• 2009

The seismic site coefficients are often used with the seismic hazard maps to develop the design response spectrum at the surface. The site coefficients are most commonly developed deterministically, while the seismic hazarde maps are derived probabilistically. There is, hence, an inherent incompatibility between the two approaches. However, they are used together in the seismic design codes without a clear rational basis. To resolve the fundamental imcompatibility between the site coefficients and hazard maps, this study uses a novel probabilistic seismic hazard analysis (PSHA) technique that simulates the results of a standard PSHA at a rock outcrop, but integrates the site response analysis function to capture the site amplification effects within the PSHA platform. Another important advantage of the method is its ability to model the uncertainty, variability, and randomness of the soil properties. The new PSHA was used to develop fully probabilistic site coefficients for site classes of the seismic design code and another sets of site classes proposed in Korea. Comparisons highlight the pronounced discrepancy between the site coefficients of the seismic design code and the proposed coefficients, while another set of site coefficients show differences only at selected site classes.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.05a
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• pp.131-135
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• 2001

Recently, Internet is used widely. Many Web sites, however, are not designed based on user's view. So, this research aimed at grasping the user needs and structure of Web site which user used easily. First, to grasp user needs, questionnaires about the motivation, the purpose and the evaluation items of Web page were done. As a result, we found the easiness for the user. Next, we made subjects operated test pages in which the number of classes and the amount of information were changed. We collected the quantitative data of the optimum number of classes, amount of information and retrieval time. As a result, there was a significant difference in each numerical value. The results of this research are available when constructing a web site. so, usability of Web site can be improved by them.

• The Korean Journal of Ecology
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• v.24 no.4
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• pp.205-211
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• 2001

The floristic composition and structure of the Oriental Arbor-viate forest, natural monument no. 1, were investigated in the Daegu city, southeastern Korea. Vegetation stratification have four layers including tree (＞5m), subtree (2m-5m), shrub (1m-2m) and herbs (＜1m), which occupied 63.8%, 10.7%, 12.1% and 49.4%, respectively. The vegetation of the study area were divided into Artemisia keiskeana - Quercus variabilis and Pyrrosia linearifolia-Thuja orientalis (OAV) communities. Frequency distribution for diameter classes of the Oriental Arbor-vitae population showed a reverse-J shape. The result suggests that the OAV forest of this site might maintains continuously the present state. The annual radial growth of OAV, Pinus densiflora and Quercus variabilis, the dominant species of the present site showed 0.29, 1.01 and 1.28 mm/year, respectively. Competition of OAV with theh other species including P. densiflora and Q. variabilis could influence negatively on the growthand survival of OAV forest in this site.

• Molecules and Cells
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• v.39 no.1
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• pp.53-59
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• 2016

Peroxiredoxins are cysteine-dependent peroxide reductases that group into 6 different, structurally discernable classes. In 2011, our research team reported the application of a bioinformatic approach called active site profiling to extract active site-proximal sequence segments from the 29 distinct, structurally-characterized peroxiredoxins available at the time. These extracted sequences were then used to create unique profiles for the six groups which were subsequently used to search GenBank(nr), allowing identification of ~3500 peroxiredoxin sequences and their respective subgroups. Summarized in this minireview are the features and phylogenetic distributions of each of these peroxiredoxin subgroups; an example is also provided illustrating the use of the web accessible, searchable database known as PREX to identify subfamily-specific peroxiredoxin sequences for the organism Vitis vinifera (grape).