• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.281-285
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• 2012

The aim of this research was carried out that leafty and tonic vegetable using garlic (Allium victorialis L. var. platyphyllum Makino) makes use of landscape ground-cover plant. Following shading level treatments (30%, 50%, 80%), garlic was cultivated to investigate plant growth characteristic and chlorophyll content. Leaf number of all treatments was unaffected, and 80% shading treatment had grown vigorous growth 16.8 cm leaf length and 10.1 cm leaf width compared to 13.4 cm leaf length and 7.3 cm leaf width for the non-shading treatment. Fresh weight of non-shading treatment was better than those of three shading treatments, however, 80% shading treatment had produced 10.4 g fresh weight of stem part compared to 8.5 g for the for the non-shading treatment. The chlorophyll content of the 50 and 80 shading treatments showed 42.8% and 40.5% respectively. These treatments increased 36.7% chlorophyll content compared to non-shading treatments. Following shading level treatments, growth characteristics of garlic in 80 shading level treatment shows outstanding growth and it is worthy of planting as shading ground-cover plants.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.87-94
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• 1991

This study was carried out to determine the optimal seeding rate of Korean lawngrass in three different soil textures. The results obtained are summarized as follows;1.In early development, there were not significant differences in leaf length and width except for leaf width in mean seeding rates. And there was significant difference in tillering number. Tillering number of Korean lawngrass grown in sandy clay loam soil was more abudant than that grown in sandy clay and sandy loam soils.2.The rate of ground cover of Korean lawngrass grown in sandy clay loam soil was faster than that in other soils. The ground cover rate was faster in the following order: 15, 12, 10, 7, 5, 3 kg/10a. But in sandy clay loam soil, it was showed that the plot seeded at 12kg/10a be faster than that at l5kg/10a. Plots seeded from 5 to 15kg/10a in sandy clay loam soil and 15kg/10a in sandy clay soil were showed the 100% ground cover during the period of the year seeded.3.There were not significant differences in dry weight of each part measured at 11 and l4months after seeding. But there were significant differences in dry weight of shoot and total dry weight. Total and shoot dry weight of Korean lawngrass grown in sandy clay loam soil were heavier than that in others. 4.It was revealed that the optimal seeding rate in sandy clay loam soil was 12 kg/10a. But it was suggested that the optimal seeding time and rate in each soil textures be undertaken in future.

• Journal of Korea Water Resources Association
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• v.57 no.5
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• pp.321-332
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• 2024

Understanding the status of surface cover in riparian zones is essential for river management and flood disaster prevention. Traditional survey methods rely on expert interpretation of vegetation through vegetation mapping or indices. However, these methods are limited by their ability to accurately reflect dynamically changing river environments. Against this backdrop, this study utilized satellite imagery to apply the Random Forest method to assess the distribution of vegetation in rivers over multiple years, focusing on the Naeseong Stream as a case study. Remote sensing data from Sentinel-2 imagery were combined with ground truth data from the Naeseong Stream surface cover in 2016. The Random Forest machine learning algorithm was used to extract and train 1,000 samples per surface cover from ten predetermined sampling areas, followed by validation. A sensitivity analysis, annual surface cover analysis, and accuracy assessment were conducted to evaluate their applicability. The results showed an accuracy of 85.1% based on the validation data. Sensitivity analysis indicated the highest efficiency in 30 trees, 800 samples, and the downstream river section. Surface cover analysis accurately reflects the actual river environment. The accuracy analysis identified 14.9% boundary and internal errors, with high accuracy observed in six categories, excluding scattered and herbaceous vegetation. Although this study focused on a single river, applying the surface cover classification method to multiple rivers is necessary to obtain more accurate and comprehensive data.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.426-428
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• 2003

Optical and microwave remote sensing data have been widely used in land cover and land use classification. Thanks to the spectral absorption characteristics of ground object in visible and near infrared region, optical data enables to extract different land cover types according to their material composition like water body, vegetation cover or bare land. On the other hand, microwave sensor receives backscatter radiance which contains information on surface roughness, object density and their 3-D structure that are very important complementary information to interpret land use and land cover. Separate use of these data have brought many successful results in practice. However, the accuracy of the land use / land cover established by this methodology still has some problems. One of the way to improve accuracy of the land use / land cover classification is just combination of both optical and microwave data in analysis. In this paper for the research, the author used LANDSAT TM scene 127/45 acquired on October 21, 1992, JERS-1 SAR scene 119/265 acquired on October 27, 1992 and aerial photographs taken on October 21, 1992. The study area has been selected in Hanoi City and surrounding area, Vietnam. This is a flat agricultural area with various land use types as water rice, secondary crops like maize, cassava, vegetables cultivation as cucumber, tomato etc. mixed with human settlement and some manufacture facilities as brick and ceramic factories. The use of only optical or microwave data could result in misclassification among some land use features as settlement and vegetables cultivation using frame stages. By combination of multitemporal JERS-1 SAR and TM data these errors have been eliminated so that accuracy of the final land use / land cover map has been improved. The paper describes a methodology for data combination and presents results achieved by the proposed approach.

• Journal of Korean Tunnelling and Underground Space Association
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• v.21 no.6
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• pp.735-747
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• 2019

Due to the lack of ground space by urbanization, the demand of utility tunnels for laying social facilities is increasing. During the construction of a utility tunnel in downtown area using a shield TBM, various problems may occur when difficult ground is encountered such as mixed ground and cobbly ground. Thus, in this study, using MIDAS GTS NX (Ver. 280), a numerical analysis was performed on characteristics of difficult ground, reinforced area, depth of cover and groundwater level to analyze the optimal ground reinforced area according to combination of parameters. As a result, it was difficult to secure stability in unconstrained excavation cases on both the mixed ground and the cobbly ground. However, when ground reinforcement grouting as much as 2.0D is applied, convergence occurred within the allowable limit, except for mixed ground with a depth of cover 30 m. In addition, excessive leakage occurred during excavation of both the mixed ground and the cobbly layers. It was able to secure stability after applying waterproof grouting.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.97-107
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• 2015

Research was initiated to investigate a vegetation characteristics of the species of ground cover plants mixed with herbeceous and woody plants on a cut slope. 4 different ground cover plants (Miscanthus sinensis var. purpurascens, Pennisetum alopecuroides, Festuca arundinacea and Zoysia japonica) were seeded at the same rate of $10.0g/m^2$ with herbaceous plants (Lotus corniculatus var. japonicus, Dianthus sinensis, Aster yomena, Chrysanthemum zawadskii and Coreopsis drummondii L) at the total seeding rate of $7.5g/m^2$ and native woody plants (Lespedeza bicolor Turcz, Indigofera pseudo-tinctoria and Albizzia julibrissin) at the total seeding rate of $7.5g/m^2$, respectively. This experiment was treated with 3 replications on a randomized block design. Data such as surface coverage rate(%), the germinating number, plant height and visual quality were analyzed. There were no statistic differences observed in the soil hardness and the soil moisture content while a significant difference was observed in the surface coverage rate and the germinating number. The surface coverage rate and the germinating number were significantly high in the Pennisetum alopecuroides plot when compared with the Miscanthus sinensis var. purpurascens plot, the Festuca arundinacea plot and the Zoysia japonica plot, respectively from the viewpoint of ground covers. Especially, the surface coverage rate was considerably low in the Festuca arundinacea plot. However, the surface coverage rate and the germinating number were no statistic differences observed in this treatment from the viewpoint of herbaceous and woody plants. Also, both of the plant height and visual quality were high in the Pennisetum alopecuroides plot when compared with the Miscanthus sinensis var. purpurascens plot, the Festuca arundinacea plot and the Zoysia japonica plot, respectively. We concluded that Pennisetum alopecuroides was the optimum plant from the treated ground covers mixed with native woody and herbaceous plants for the balanced emergence from the viewpoint of the ecological slope vegetation.

• Weed & Turfgrass Science
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• v.4 no.1
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• pp.71-75
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• 2015

Playground is frequently used for physical and sports activity by students as well as by common people, which is constructed with various cover materials on the ground. This research surveyed the surface temperature in Kyungpook National University Sangju campus playground which is covered with various cover materials [bare field, zoysiagrass (Zoysia japonica) turf field, urethane track, concrete field, epoxy field and artificial turf field] in Sangju, Gyeongsangbukdo, Korea. Temperature was measured 4 times per day at 09:00, 12:00, 15:00, and 18:00 from May to October 2014 in surface and 1 m height above the ground. Surface temperature was different, depending on cover materials and survey time. Bare field and zoysiagrass turf field was lower surface temperature than other sites. Higher surface temperature site was different depending on survey time. Urethane track and artificial turf field was hotter than other sites at 12 and 15 hours, however concrete and epoxy field was hot at 18 hours. One meter above ground temperature was the highest in artificial turf field except at 18 hours. So natural turf, zoysiagrass playground will increase the athletic performance by reduce the surface and above ground temperature.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.4
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• pp.17-23
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• 2013

The purpose of this study was to provide information on management and apply it to a roadside ground cover plant understanding the capacity of calcium chloride in the plant. The experimental group was composed of the ratio control group of calcium chloride, 0.5%, 1.0%, and 3.0% in 500g of soil. Plant materials were selected and measured according to their ecological characteristics such as ground cover plant, Pachysandra terminalis, Hosta plantaginea, Trachelospermum asiaticum, Vitex rotundifolia, Euonymus japonica and Callicarpa japonica. The acidity of the amended soil was increased gradually depending on the treatment and conductivity was continually decreased. The EX-Ca increased after the treatment, but decreased in the middle of the experiment. Pachysandra terminalis, Trachelospermum asiaticum and Euonymus japonica were able to grow and survive at the ratio of 0.5%. Hosta plantaginea and Vitex rotundifolia were able to survive at the ratio of 1.0%. Hosta plantaginea, the possible state can absorb salts due to moisture and, can be applied to ground cover plants in the roadside. The growth and development of Callicarpa japonica was poor and the leaves were open to grow for calcium chloride treatment except the control group. It was concluded that Callicarpa japonica was very sensitive to calcium chloride.

• Korean Journal of Organic Agriculture
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• v.25 no.1
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• pp.85-99
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• 2017

The study was compared for ability to supply macro-nutrients between time and height of mowing to establish alternate technique of a chemical fertilizer with 9-year old 'Niitaka' pear (Pyrus pyrifolia Nakai) trees in a pesticide-free orchard in 2009. Rye and hairy vetch were sown together during fall 2008. Four types of mowing time treatments were included; mowing on April 18+May 28, on April 28+June 8, on May 8+June 18, and on April 18+May 18+June 18. Mowing height treatment included mowing at $3{\pm}1cm$, $7{\pm}1cm$, and $13{\pm}1cm$ on April 18 or June 8. Mowing on May 8+June 18 increased the most dry weight of ground cover and vegetation to 14,480 kg per ha among the mowing time treatments, resulting in the greatest production of T-N (total nitrogen; 292 kg) and K (396 kg) per ha on the soil. Mowing at $7{\pm}1cm$ decreased the most dry weight of ground cover and vegetation to 11,970 kg per ha among the mowing height treatments, resulting in the lowest production of T-N (265 kg), P (111 kg) and K (333 kg) per ha in a soil. Ground cover treatments increased soil organic matter contents, regardless of mowing treatment methods.

• Korean Journal of Remote Sensing
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• v.29 no.3
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• pp.315-324
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• 2013

Spatial information of snow cover and depth distribution is a key component for snowmelt runoff modeling. Wide snow cover areas can be extracted from NOAA AVHRR or Terra MODIS satellite images. In this study eight sets of annual snow cover data (1997-2006) in two mountainous watersheds (A: Chungju-Dam and B: Soyanggang-Dam) were extracted using NOAA AVHRR images. The distribution of snow depth within the Snow Cover Area (SCA) was generated using snowfall data from ground meteorological observation stations. Snow depletion characteristics for the two watersheds were analyzed snow distribution time series data. The decreased pattern of SCA can be expressed as a logarithmic function; the determination coefficients were 0.62 and 0.68 for the A and B watersheds, respectively. The SCA decreased over 70% within 10 days from the time of maximum SCA.