• Journal of Korean Society of Forest Science
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• v.100 no.1
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• pp.42-51
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• 2011

This study was conducted to analyze correlation of above- and below-ground biomass and to drive regression equation suitable for estimating standing tree biomass between natural and planted stands of Pinus densiflora for. erecta of one age-class in Gangwon province, Republic of Korea. Total 40 trees, 10 from the naturally regenerated and 10 from the planted stands in each of two studied sites, were uprooted to measure height, diameter at root color (DRC), and the dry weights of stem, branches, and needles. The length, weight, and volume of the main and horizontal roots were also measured. Most of the above-ground traits except height were highly correlated with most of the other above-ground traits and the below-ground traits except the length of roots (p < 0.05). Especially, the DRC, which is measured easily on the standing tree, was highly correlated with most of the traits in all studied stands (p < 0.01). Thus, the DRC would be the most desirable trait to estimate not only above-ground biomass but also below-ground biomass. However, height was not a good variable to estimate standing tree biomass of Pinus densiflora for. erecta of one age-class in Gangwon province because it was not correlated with most of other traits. Regression equations derived from the current study could be used effectively as a basic data for estimating above-ground and below-ground biomass using DRC.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.29.3-30
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• 2015

We introduce an advanced one-to-one galaxy correspondence method that populates dark matter halos with galaxies by tracing merging histories of most bound member particles (MBPs) identified in simulated virialized halos. To estimate the survival time of a satellite galaxy, we adopt several models of tidal-destruction time derived from an analytic calculation, isolated galaxy simulations, and cosmological simulations. We build mock galaxy samples for each model by using a merging tree information of MBPs from our new Horizon Run 4 N-body simulation from z = 12 to 0. For models of galaxy survival time derived from cosmological and isolated galaxy simulations, about 40% of satellites galaxies merged into a certain halo are survived until z = 0. We compare mock galaxy samples from our MBP-galaxy correspondence scheme and the subhalo-galaxy scheme with SDSS volume-limited galaxy samples around z = 0 with $M_r-5{\log}h$ < -21 and -20. Compared to the subhalo-galaxy correspondence method, our method predicts more satellite galaxies close to their host halo center and larger pairwise peculiar velocity of galaxies. As a result, our method reproduces the observed galaxy group mass function, the number of member galaxies, and the two-point correlation functions while the subhalo-galaxy correspondence method underestimates them.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.9
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• pp.1059-1064
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• 2015

To write a medical record using SNOMED CT standard clinical terminologies, it is necessary to find and select an appropriate terminology from the huge volume of terminologies within short time. Using previous SNOMED CT search browsers, it is very difficult to select appropriate one from search results since they provide a simple list-up of similar candidate terminologies. This paper proposes a novel search browser which supports effect searching of clinical terminology by utilizing characteristics of SNOMED CT. The proposed system provides a simplified tree-view representing hierarchical structures of search results which enables fast selection of appropriate terminology from the search results. Design and Implementation of the system proves effectiveness of the proposed approach.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.172-175
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• 2005

The numerical simulation is performed for the acoustic emission and the wave propagation due to fiber breakage in single fiber composite plates by the finite element transient analysis. The acoustic emission and the following wave motions from a fiber breakage under a static loading is simulated to investigate the applicability of the explicit finite element method and the equivalent volume force model as a simulation tool of wave propagation and a modeling technique of an acoustic emission. For such a simple case of the damage event under static loading, various parameters affecting the wave motion are investigated for reliable simulations of the impact damage event. The high velocity and the small wave length of the acoustic emission require a refined analysis with dense distribution of the finite element and a small time step. In order to fulfill the requirement for capturing the exact wave propagation and to cover the 3-D simulation, we utilize the parallel FE transient analysis code and the parallel computing technology.

• Journal of Biomedical Engineering Research
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• v.31 no.6
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• pp.427-433
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• 2010

Although tracking methods are efficient and popular for vessel segmentation, they require a seed to initiate an instance of tracking. In this paper, a new method to detect new seeds for tracking of arterial segments from CT angiography (CTA) and to construct a vascular structure is proposed. The proposed algorithm is based on shape analysis of connected components in a volume of interest around a vessel segment which was already extracted by tracking. The eigenvalues of the covariance matrix are used as the shape features for detection. The experimental results on actual clinical data showed that the results totally revealed the arterial tree not hindered by bone or veins. In visual comparison to a method which combines registration and subtraction of both pre-contrast and post-contrast CT volumes, the proposed method produced comparable results to the reference method and were confirmed of its feasibility for clinical use of reducing the cost and burden of patients.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.5
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• pp.594-601
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• 2015

The purpose of this research is to propose a maintenance support system for deciding assembly sequence of the product and appropriate tools that are used to assembly and disassembly of parts in the product when geometric properties of the product. The digital maintenance system (DMS) is developed to generate the maintenance guideline and the initial experiment is conducted especially for an underwater weapon system with cylindrical structure. DMS considers four factors to find the efficient assembly and disassembly procedure automatically: (1) assembly tree, (2) properties of each part, (3) distance from the center of the product, and (4) volume. Based on the factors, DMS simulate the movement of each tool virtually and the properties of tools are investigated to find an appropriate tool for using assembly and disassembly of each part in the product. The proposed approach integrates modeling, simulation, data configuration, and virtual reality to allow a development of preliminary maintenance guidance.

• Environmental Analysis Health and Toxicology
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• v.22 no.2 s.57
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• pp.177-184
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• 2007

Gaseous organochlorine pesticides (OCPs : heptachlor epoxide, p, p'-DDE, ${\gamma}-HCH,\;{\alpha}-chlordane,\;{\gamma}-chlordane$ and trans-nonachlor) concentration was measured using PUF high volume sampler from June, 2000 to June, 2002 in the semi-rural atmosphere. The OCPs concentration in atmosphere, which is estimated by the slope (m) of Clausius-Clapeyron equation and phase-transition energy $({\Delta}H)$, was influenced by revolatilization from environmental matrix (soil, water and tree leaves) and a long range transportation of air mass. But the former affected OCPs concentration more than the latter. The degradation rate constants (k) of OCPs calculated using multiple regression analysis and revised standard temperature method were in good agreement each other. The value of k of ${\gamma}-HCH$ was very low as -0.0007, but the range of k of other components were $-0.00l8{\sim}-0.0038$. The half-life $({\tau})$ which was calculated by k of ${\gamma}-HCH$ was 2.6 years-the longest one, but that of heptachlor epoxide was in 0.5 year-the shortest one. $({\tau})\;of\;{\alpha}-chlordane,\;{\gamma}-chlordane$ and trans-nonachlor in technical chlordane was 1.0, 1.1 and 0.7 year respectively.

• Journal of the Korean Wood Science and Technology
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• v.7 no.1
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• pp.3-7
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• 1979

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potentially valuable resources. As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Pinus, Quercus and Populus grown in korea can be enhanced by Knowing its chemical Properties. Specially, uses of bark in mulching, growing media and soil amendment can be enhanced by knowing pH and C.E.C values. In this paper, an investigative study is carried out on the pH-and C.E.C-values. The results may be summarized as follows: 1. Bark is acid in nature, and pH values of bark varying from 3.3 to 4.7, is lower than that of wood.pH value of Pinus is the lowest. 2. Cation exchange capacity of bark is greater than that of wood, silt loam soil, and wheat straw.CEC of bark is 45.7 meq/100gm in Pinus, 41.8 meq/100gm in populus, 37.8 meq/100gm in Quercus.

• Journal of Forest and Environmental Science
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• v.34 no.2
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• pp.108-118
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• 2018

Biomass determination of species-specific in forest ecosystem by semi-destructive measures requires the development of allometric equations; predict aboveground biomass observable independent variables such as, Diameter at Breast Height, Height, and Volume are crucial role. There has not been equation of this type in mountain Chuqala natural forest. In this study two species namely, Hypericum revolutum Vahl. & Maesa lanceoleta Forssk. with tree diameter classes (15-20, 20.5-25, and 25.5-35 cm), with the purpose of conducting allometric equations were characterized. Each species assumed considered individually. For the linear model fit the two observed variable DBH, H and V were preferred for the prediction of above ground biomass. The best fitted model choose among the two formed model were identified using Akaike Information Criterion (AIC), and $R^2$ and adjacent $R^2$. Based on this the best fit model for Hypericum revolutum Vahl. was AGB=-681.015+4,494.06 (DBH), and for Maesa lanceoleta Forrsk. was. AGB=-936.96+5,268.92 (DBH).

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.49-49
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• 2017

Sugar palm (Arenga pinnata (Wurmb.) Merr.) grows naturally under shading of tree canopy, therefore shading levels take a main role for an optimal growth of sugar palm seedlings. The study was conducted to examine the effect of shading levels on the seedlings growth of sugar palm for up to 11 months under four shading levels: S0 (100% of full sunlight or non-shading), S1 (32% shading level), S2 (56% shading level), and S3 (64% shading level). Sugar palm seedlings grown under the shade (32, 56, and 64%) showed better plant height, stem diameter, leaf size, petiole and rachis length, chlorophyll content, root fresh and dry weights, root volume, and total biomass than those grown without shading. Although there were no significant different responses among the shading treatments on plant height, biomass dry weight, leaf morphological characters, chlorophyll content, and SPAD value, the S2 treatment showed a significant effect on a better root characters. Therefore, it can be concluded that the S2 treatment, 56% shading level, is an optimal shading condition for sugar palm seedlings.