• Journal of Korean Society of Forest Science
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• v.19 no.1
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• pp.49-54
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• 1973

Surveys of stock volume on steep and vast expanse of mountains, involves various difficulties. And it is extremely uneconomical in forest management point of view, to spend lots of time and man power for surveying such tree volume as the value is much cheaper in comparison with volume and weight. Therefore, a stand volume table estimate easely stock volume per hectare basis from aerial photographs was prepared and correlations to stand volume among factors affecting tree volumation, were studied. Data were 114 places selected from planted Korean white pine, Pinus koreiensis Sieb. et Zucc. stands in Kwangnung Experiment Forest and were computed and analysed by the means of the quantification in the multi-variate statistical analysis. Electronic Data Processing System was applied for data processing at Korean Instiute of Science and Technology. Coefficients of multiple correlations of stand volume table was ranged 0.85~0.88.

• Journal of Environmental Science International
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• v.31 no.11
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• pp.901-910
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• 2022

The aim of this study was to investigate the amount (i.e., retention volume) and chemical composition of Natural volatile organic compounds (NVOCs) across different sites in a temperate forest. The three forest sites that were considered include riparian zones (site 1), streams (site 2), and densely-canopied areas (site 3). From May to October 2021, a mini pump was used to measure the collected NVOCs. These measurements were conducted once a month, from 10:30 am to 11:30 am; these times encompass peak visitation times. In the tree layers of the site 1 and 2, Quercus acuta was dominant, whereas Camellia japonica dominated their subtree layers. On the other hand, the tree layer of site 3 was dominated by Castanopsis sieboldii, whereas Camellia japonica dominated its subtree layer. The retention volume and chemical composition of NVOCs was as follows: benzaldehyde (107.528ppm), α-pinene (37.868ppm), linalool (16.258ppm), eucalyptol (14.818ppm), and sabinene hydrate (14.679ppm). In particular, the retention volume of benzaldehyde decreased as temperature increased. In contrast, the retention volume of α-pinene increased as the temperature increased. The differences in forest topography across the studies sites were in the following order: riparian area> forest area> stream area.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.150-164
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• 2022

This study was conducted to provide basic information for the development of silvicultural guidelines and manuals. This was achieved through analysis of tree and stand characteristics according to the first and second thinning in Korean white pine plantations. Data were collected from permanent plots installed at Korean white pine plantations according to thinning intensity, and residual tree and stand variables, including diameter at breast height (DBH), volume, and mortality at age 19-43, were analyzed using data repeatedly collected in 4-5 measurements by experiments. According to one-way variance of analysis, tree DBH and volume were significantly different according to thinning intensity (p<0.05). DBH distribution was skewed to the left side over time as thinning intensity was heavier. Thus, tree DBH values were larger in heavy thinning plots with increased age. The periodic annual increment (PAI) of DBH was higher with heavier thinning intensity and fewer years after thinning. The PAI range by thinning intensity was 0.48-0.95 cm/year at age 19-24. In addition, the PAI increased in heavy thinning plots after the second thinning; The PAI range by thinning intensity was 0.29-0.67 cm/year after the second thinning at age 37-42. The PAI of tree volume differed according to thinning intensity, and the PAI value did not decrease obviously, in contrast to the pattern of the DBH PAI. Stand volume was generally higher in high-density stands, and the PAI of stand volume was high in unthinned and light thinning plots. Mortality was highest in unthinned plots, and the differences in mortality according to thinning intensity increased over time. Consequently, the growth of DBH and tree volume was lower as stand density increased, but this growth was facilitated with appropriate first and second thinning operations.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.12a
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• pp.661-667
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• 1999

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.5
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• pp.42-52
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• 2024

This study aimed to utilize LiDAR, a high-precision surveying technology, to compensate for errors caused by human measurements and obtain accurate and consistent data for tree volume measurement. To this end, a comparative verification of measured tree volume values by each method was conducted using terrestrial LiDAR (TLS) and drone LiDAR (ALS). As a result of examining the 3D data of trees according to the measurement method, it was confirmed that the output data of terrestrial LiDAR had insufficient crowns, and the output data of drone LiDAR had insufficient trunks. Therefore, the study attempted to establish a complete form by aligning the two data sets. In addition, two verifications of tree volume values were conducted using the point cloud data output by each method. As a result of the first verification, the accuracy verification of terrestrial LiDAR showed a difference of 1-3 m in tree height compared to the existing field survey measurement value. The discrepancy is believed to be due to the density of trees or terrain and features according to the principle of LiDAR. In the second verification, terrestrial LIDAR, drone LIDAR, terrestrial LIDAR, and drone LIDAR alignment data were compared. In order to compare the tree height and breast height diameter according to each measurement method, Bland-Altman descriptive statistics were performed based on the field survey measurement values. Considering the results, the drone LIDAR measurement method showed the highest repeatability coefficient, indicating the least consistency, while the drone and terrestrial LIDAR alignment data values showed the lowest repeatability coefficient, indicating high consistency. For the breast height diameter, the terrestrial LIDAR measurement method showed a low repeatability coefficient similar to the drone and terrestrial LIDAR alignment data values, indicating high consistency. Therefore, it is judged that the method of overlapping drone and terrestrial LIDAR data when measuring the structure of trees can derive more precise tree volume information.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.225-240
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• 2015

The effect of passing pedestrians'characteristics on locational goodwill was empirically modeled and tested. The theoretical basis for the study was central place theory, bid rent and, agglomeration theory, and demand externality theory. The data included information on goodwill, retail rents and passing pedestrians' characteristics in 100 retail trade areas in Seoul. The empirical model was tested with the sample of 1,307 retail units in Seoul, South Korea. The data set was analyzed with the Classification and Regression Tree software. As the results, using the regression tree method, the variables does affect locational goodwill in the each retail trade area were the volume of pedestrians around 2:00 pm on weekdays, volume of pedestrians around 4:00 pm on weekdays, and volume of pedestrians around 8:00 pm on weekdays. In summary, not only the economic base in the retail trade area but also the volume of passing pedestrians should be considered to determine the locational goodwill.

• The Journal of Natural Sciences
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• v.18 no.1
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• pp.91-97
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• 2007

The Korean name "Bizooki" tree was named by the shape of winter bud which is like a slim bow. There are four scientific names in the tree which are Cleyera japonica Thunberg, Cleyera ochnacea DC, Sakakia ochnacea Nakai, and Ternstroemia gymnanthera. And the English name are Japanese Ternstroemia and Japanese Cleyera. "Bizooki" tree has planted at Buddhist temples in Japan for the ritual. The best result of stem cutting in "Bizooki" tree, 100 percent of rooting, could be accomplished in July when cuttings were done on the mixture-soil containing the same rates by volume of vermiculite, peatmoss and perlite with cuts processed with IBA 1,000 mg/l under the circumstances that 70% of shade, plastic mulching, and mist were conditioned.

• Journal of information and communication convergence engineering
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• v.22 no.3
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• pp.207-214
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• 2024

In wireless sensor networks, the implementation of routing protocols is crucial owing to their limited computational capacities. Tree routing is a suitable method in wireless sensors owing to its minimal routing overhead. However, single-hop metric schemes, such as hop count, cause congestion at specific nodes, whereas multiple metric schemes cannot control dynamically changing network environments. To address these issues, we propose a scheme to implement enhanced tree routing with adaptive metrics based on hop count. This approach assigns different weights to metrics to select suitable parent nodes based on hop count. The parent-selection algorithm utilizes hop count, buffer occupancy, and received signal strength indicator (RSSI) as metrics. This study evaluates the performance through simulation scenarios to analyze whether improvements can be made to address problems encountered in traditional tree routing. The performance metrics include packet delivery speed, throughput, and end-to-end delay, which vary depending on the volume of network traffic.

• 한국전산유체공학회:학술대회논문집
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• 2006.10a
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• pp.9-10
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• 2006

A numerical method for simulating tree surface flows including the surface tension is presented. Numerical scheme is based an a fractional-step method with a finite volume formulation and the interface between liquid and gas is tracked by Volume of Fluid (VOF) method. Piecewise Linear Interface Calculation (PLIC) method is used to reconstruct the interface and the surface tension is considered using a Continuum Surface Force (CSF) model. Several free surface flow phenomena were simulated to show its effectiveness to find such phenomena.

• Journal of Climate Change Research
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• v.6 no.4
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• pp.357-366
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• 2015

This study was conducted to estimate carbon stocks of Quercus serrata with drawing volume of trees in each tree height and DBH applying the suitable stem taper equation and tree specific carbon emission factors, using collected growth data from all over the country. Information on distribution area, tree number per hectare, tree volume and volume stocks were obtained from the $5^{th}$ National Forest Inventory (2006~2010), and method provided in IPCC GPG was applied to estimate carbon storage and removals. Performance in predicting stem diameter at a specific point along a stem in Quercus serrata by applying Kozak's model,$d=a_1DBH^{a_2}a_3^{DBH}X^{b_1Z^2+b_2ln(Z+0.001)+b_3{\sqrt{Z}}+b_4e^Z+b_5({\frac{DBH}{H}})}$, which is well known equation in stem taper estimation, was evaluated with validations statistics, Fitness Index, Bias and Standard Error of Bias. Consequently, Kozak's model turned out to be suitable in all validations statistics. Stem volume tables of Quercus serrata were derived by applying Kozak's model and carbon stock tables in each tree height and DBH were developed with country-specific carbon emission factors ($WD=0.65t/m^3$, BEF=1.55, R=0.43) of Quercus serrata. As a result of carbon stock analysis by age class in Quercus serrata, carbon stocks of IV age class (11,358 ha, 36.5%) and V age class (10,432; 33.5%) which take up the largest area in distribution of age class were 957,000 tC and 1,312,000 tC. Total carbon stocks of Quercus serrata were 3,191,000 tC which is 3% compared with total percentage of broad-leaved forest and carbon sequestration per hectare(ha) was 3.8 tC/ha/yr, $13.9tCO_2/ha/yr$, respectively.