• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.71-82
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• 2023

Forest biomass is used as a representative indicator of forest size, maturity, and productivity. Therefore, quantitative evaluation is important for management and harvest as well as the evaluation of ecosystem functions and services including CO₂ absorption. The allometric equation is a widely used method for estimating the value of each component through the relative growth rate of plants. Recently, studies indicated that the relative growth of trees is changing because of the increased CO₂ concentration in the atmosphere and the resulting climate change, raising the need to review the previously developed relative growth models and coefficients. In this study, the height-diameter at breast height (DBH) relationships of four major tree species in Korea [(Pinus densiflora (PD), Larix kaempferi (LK), Quercus variabilis (QV), and Quercus mongolica (QM)] were analyzed using the 5th-7th National Forest Inventory (NFI) data. Furthermore, these results were compared with the present yield table from the National Institute for Forest Science. This analysis revealed that the expected height for the same DBH increased as the NFI progressed. For example, in model analysis, the expected heights for PD, LK, QV, and QM for DBH of 25 cm were 12.48, 19.17, 14.47, and 13.19 m, respectively, in the 5th NFI data. In the 7th NFI data, these values were estimated as 13.61 (+9.1%), 21.58 (+12.7%), 15.76 (+8.9%), and 13.93 m (+5.6%), respectively. These results indicate that the major tree species in South Korean forests currently are more vigorous in height growth than in diameter growth when compared to the height-DBH development trends by tree species identified through past survey data.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.6
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• pp.965-972
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• 2017

Assessment of vulnerability of water use to climate change include a variety of climate change scenarios. However, in most future vulnerability studies, only the climate change scenarios are used and not the future scenarios of social and economic indicators. Therefore, in this study, we applied the Representative Concentration Pathway (RCP) climate change scenario and Shared Socioeconomic reference Pathway (SSP) developed by IPCC to reflect the future. We selected indicators for estimating the vulnerability of water use, and indices were integrated with a multi-criteria decision making approach - Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The indicator data utilized national statistics and reports, social and economic scenarios, and simulated results from the Soil and Water Assessment Tool (SWAT) model which reflects climate change scenario. Finally, we derived the rankings of water use vulnerability for the short-term future (2020) and mid-term future (2050) within the Han River watershed. Generally, considering climate change alone and considering climate change plus social and economic changes showed a similar spatial distribution. In the future scenarios, the watershed rankings were similar, but showed differences with SSP scenario in some watersheds. Therefore, considering social and economic changes is expected to contribute to more effective responses to climate change.

• Journal of Wetlands Research
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• v.18 no.4
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• pp.350-356
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• 2016

The biggest factor in the success of breeding animals is selection of foods, which is determined by quality and quantity of habitats(Newton, 2003), in the case of This high biomass wetlands as an indicator of ecosystem function about Common Kestrel's choice of hunting area is expected to be an important clue of quality and quantity of habitats. For this study, it is divided into four types(Glasslands, Paddy fields, Dry fields, Rparian land) about Common Kestrel's hunting area in Yugu-eup, Gongju-si, Chungcheongnam-do, Recorded the behavior of Common Kestrel for three years during the breeding season from March to June(2014~2016). Result of investigation, hunting area showed a high hunting behavior in riversides and flight-hunting was frequently investigated from may to June. In addition flight-hunting's main food acquisition is mammal(the vole), while perching behavior's main food acquisition is insect according to the fact flight-hunting were mainly done in riversides, perching behavior were highly investigated than flight-hunting at glasslands and paddy fields and dry field. Hunting spot's coverage rate of plants covering the ground showed differences depending on hunting areas, but height of plants were not significant. Height of the plant according to hunting methods of flight-hunting to catch mammal(vole) was analyzed to prefer lower height than perching behavior Based on these results riversides are considered as a very important environmental factors for Common Kestrel's prey selection in breeding session.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.1
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• pp.3-12
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• 2009

Ozone tolerance of tree species was determined by standard index of physiological damages and biochemical defense responses under short-term ozone exposure. At the end of 150ppb $O_3$ fumigation, photosynthetic characteristics and antioxidative enzyme activities were analyzed in the leaves of five species(Koelreuteria paniculata, Firmiana simplex, Styrax japonica, Fraxinus rhynchophylla, Viburnum sargentii). Injury index was determined by the effect of ozone on photosynthetic parameters and malondialdehyde(MDA) content, and tolerance index was calculated using the rate of increase in superoxide dismutase(SOD), ascorbate-peroxidase(APX), glutathione reductase(GR) and catalase(CAT) activities. Apparent quantum yield(AQY), carboxylation efficiency(Ce) and photo-respiration rate(PR) decreased in the leaves of five species with increasing ozone exposure time. These parameters were considered as an appropriate indicator for stress evaluation. Antioxidative enzyme activities showed various results depending on the tree species, exposure time, and enzyme types. SOD activity of K. paniculata increased with ozone exposure time, and that of F. rhynchophylla increased only after 6 hours of ozone exposure. CAT activity of $O_3$-exposed F. simplex was lower than the control. Based on standard index, ozone tolerance ability of five species was determined as two tolerant species(F. rhynchophylla > K. paniculata) and three sensitive species(S. japonica > F. simplex > V. sargentii).

• Korean Journal of Construction Engineering and Management
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• v.16 no.4
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• pp.3-11
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• 2015

Apartment developers consider the initial sales rate as an important indicator for their success of apartment development projects. They tried to achieve a secure level of initial sales rate. In spite of its importance, there is little research on the initial sales rate because of the difficulties in gathering proper data for analysis. This study, however, collects the data in initial sales rates in Su-won from various sources such as construction companies, marketing companies, sales companies and so on. By using this rare data, this study analyses the initial contract rate of apartment and estimates the initial contract rate by sales price. The result of this study shows that important of land area ratio, brand, and distance to park. It is expected that the proposed model will be used for apartment developers in sales planning phase.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6D
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• pp.803-810
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• 2011

The public interest of global warming and energy shortage is gradually increased, and the related industries also have become interested in developing eco-friendly material and technology. Warm-mix asphalt (WMA) is a result of the developments to alleviate global warming and energy problems. This WMA is produced at lower temperatures than the temperature at which hot mix asphalt (HMA) is produced. Because most tests in Superpave are developed only for the performance and maintenance of HMA produced by hot temperatures, it is difficult for the tests to identify properly the material properties and then evaluate the performances between HMA and WMA. This study deals with the development of a new protocol to differentiate HMA and WMA performance, and especially the interfacial properties between asphalt and aggregate are targeted as the performance indicator; thus, an evaluation method and guideline are suggested. The concept and idea of the test method applied in this study were modified from the DSR moisture damage test protocol. In addition, TSR test was performed to affirm the relation between the asphalt-aggregate interface and the asphalt-aggregate mixture performances. The followings are the results of this study. Shear stress at 85% linear visco-elastic complex modulus (LVE $G^*$) can be a better parameter than LVE $G^*$, which can assess the interfacial or bonding performance between asphalt and aggregate. Moreover, measuring the bonding performance in thinner film thicknesses will be a better way to evaluate the real and field situation between asphalt and aggregate. The interfacial properties' criteria to apply the newly developed test and parameter should be developed, after the asphalt mixture criteria relating to the interfacial properties are completed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.251-259
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• 2014

Securing publicness and efficiencies are the two core goals for implementing quasi-public bus system. However, researches for evaluating the quasi-public bus system with respect to the two goals have been very limited. This study represents an attempt to evaluate the system performance in these two aspects. To achieve this, a framework for performance evaluation is developed. Utilizing the framework, the 5-year performances of the quasi-public bus system in Busan are evaluated. Acess, agency and public interests are employed as criteria for publicness evaluation. Financial aspects of operators, labor, vehicle utilization, productivity and operational costs are selected as indicators for efficiency evaluation. The results show that the publicness of bus services has been vastly improved, while the efficiency has been also improved in most areas except in cost and vehicle utilization aspects. The results of this study will be of use for planners and policy-makers developing strategies for system improvement. It is hoped that this study can be further refined by adding and adjusting indicators which this study may neglect or ignore.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.542-549
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• 2020

Purpose: As nitrate nitrogen produced during fermentation of liquid fertilizer is a pollution indicator of water, in this study, four research areas where liquid fertilizer was sprayed were selected, and a model was designed to estimate the concentration of nitrate nitrogen pollution. Method: Prior to shooting on site, a spectrum library was constructed by dividing the ratio of liquid fertilizer into 5 groups: 0%, 25%, 50%, 75%, and 100%. PLSR (Partial least squares regression) method was applied to hyperspectral images acquired in the study area based on the aspect of spectrum. Result: The behavior of nitrate nitrogen was confirmed by 1st and 2nd differentiation of the spectrum of the constructed liquid fertilizer. PLSR concentration estimation modeling was implemented using images from field experiments and compared with actual concentration of nitrate nitrogen. Conclusion: When comparing the PLSR concentration estimation model with the actual concentration of nitrate nitrogen, it was measured that the detection is possible in high concentration areas where the concentration of nitrate nitrogen is 70mg/kg or more.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.490-494
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• 2017

With increasing the number of vehicles, the accident rate also goes up and the damaged vehicles should be painted as a final repair process. At the painting stage the solvent-based paint causes environmental problems. To overcome these problems waterborne refinish paint is frequently used recently. However, for waterborne refinish, the costs of insurance coverage are too expensive, and insurance reimbursement costs could be burdensome. Because of the high price of aquatic paint treatment, the service shop might charge the malicious service price. In this study, the surfactant of Surfynol 104, which is the component in the paint, was used as an indicator whether the vehicle was painted with waterborne paint. The specimen was quantitatively analyzed to contain 0.38% of the surfactant through the standard addition method with isotope substituted internal standard (IS) of fluranthene-d10 by curie point pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS).

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.6
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• pp.415-418
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• 2008

The application of sludge wastes into agricultural fields has been increasing annually in Korea. In particular, sewage sludge application has been widely accepted in decades. Sewage sludge application aid in the recycling of essential nutrients and act as a source of organic matter improving the structure and water-holding properties of the soil. The efficient use of sludge wastes, however, requires an individual assessment of waste products. This study assessed the biological characteristics of organic waste-treated lysimeter soils and develop its indicator to assess the soil health of organic waste-treated lysimeter soils. Several analytical techniques more recently developed such as restriction fragment length polymorphism (RFLP), phospholipid fatty acid (PLFA), and community level substrate utilization (CLSU) fingerprints allow for detailed analyses of soil microbial communities. PLFA and RFLP was, therefore, used in the study to characterize the microbial communities in soil without the need to isolate individual fungi and bacteria. PLFA, RFLP and CLSU have been utilized to assess microbial characteristics of the lysimeter soils with four different sludge wastes for eight consecutive years. Each of these methods was analyzed for a different aspect of soil microbial characteristics. The study would disclose those methods yielded highly reproductive results for each soil and allow distinguishing the soils based on the structures of specific geneand PLFA-pools more than CLSU fingerprints. PLFA methods, especially, revealed the same relative similarities of the treated soils based on cluster analysis of the biological characteristics. Pig manure compost-treated soil, however, was only the same relative resemblance among the three methods. These results indicated that PLFA easily assessed the biological soil characterization.