• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.603-617
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• 2017

The occurrence and management of disease and pests in six organic peach orchards were surveyed from March 2015 to March 2017. In this period, the number of certified organic and non-chemical peach farms increased to 65.5% and 31.7%, respectively. Certified organic peach farms were selected based on more than $4,000m^2$ of cultivation area and three tons of production, and their cultivation status was examined. All of the farms were either cultivated green manure crop or sod, and limited vegetation control to a minimum. For the management of soil nutrients, many farmers used livestock manure, oilcake and self-manufacturing liquid fertilizer. It was surveyed that bordeaux mixture, lime sulfur, pheromone for mating disruption of moths and plant extract were used for disease and pest control. The damage caused by the pests and diseases were 31.6% and 24.1%, respectively. The oriental fruit moth showed the highest damage rate (13.5%) in the organic peach orchards, followed by the brown rot (13.0%), peach fruit moth (7.3%) and bacterial shot hole (7.3%).

• Journal of Korean Society of Forest Science
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• v.30 no.1
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• pp.50-60
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• 1976

For finding out the proper method of developing Buxus koreana var. insularis, this study was carried out in Pokil-Do, Wan-Do, Chonnam, in 1975. The ecology, morphology and characteristics of the plant were mainly investigated and analyzed. The results are summarized as follows; 1. The small islands of the southern sea of Korea; Pokil-Do, Chin-Do and So-Huk-San-Do, turn out to be the site of the natural communities of B. koreana var. insularis. 2. The growth of the plant is fairly good in the acid soil of these islands. 3. This vegetation of composed as the three-layered communities, these communities consit of Camellia, Buxus and Cares. 4. The plant is a board leaved evergreen shrub that is tolerant to shade and native to the temperate zone. 5. The size of the leaves, fruits and seeds is slightly larger than those of B. koreans. 6. As fruiting and germination of the seeds are favorable. it is easy for us to make a number of seedlings. 7. The proper times for sowing and harvesting the seeds are around the middle of July and August, respectively. 8. The seedlings is difficult to grow in the naked ground because the germinated seeds are seriously damaged by frost. 9. The plant growth per annum is about 8 to 10cm in height, 1.5mm in diameter. It is graceful looking as the branches and leaves as of the dense foliage type 10. It is possible to develop the plant in many ways, such as; ornamental plant, bee plant, sculptural and industrial materials.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.5
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• pp.363-371
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• 2015

Feature extraction is one of the main goals in many remote sensing analyses. After high-resolution imagery became more available, it became possible to extract more detailed and specific features. Thus, considerable image segmentation algorithms have been developed, because traditional pixel-based analysis proved insufficient for high-resolution imagery due to its inability to handle the internal variability of complex scenes. However, the individual segmentation method, which simply uses color layers, is limited in its ability to extract various target features with different spectral and shape characteristics. Spectral indices can be used to support effective feature extraction by helping to identify abundant surface materials. This study aims to evaluate a feature extraction method based on a segmentation technique with spectral indices. We tested the extraction of diverse target features-such as buildings, vegetation, water, and shadows from eight band WorldView-2 satellite image using decision tree classification and used the result to draw the appropriate spectral indices for each specific feature extraction. From the results, We identified that spectral band ratios can be applied to distinguish feature classes simply and effectively.

• Journal of Korea Water Resources Association
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• v.43 no.10
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• pp.883-891
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• 2010

More recently, there have been significant changes in the forms of channels due to runoff characteristics driven by climate changes and other alterations in basin/channel environments. Particularly, increasing local deposition in major channels is being observed nationwide. Of such phenomena, it is noteworthy that flood-plains show unidirectional growth and lowering of channels within compound channels in the form of a high-flow plain. These changes are supposed to affect management of the river ecology as well as flood control. In this study, the research on channels in Korea confirmed that the phenomenon of local deposition in those channels is actually taking place, rendering a problem to be urgently addressed. Previous studies on bed changes have been focused on low channels based on bed materials distributed over the channels. However, this research has proved that surface-layer deposition of a high-flow plain is closely related with changes in the conditions of ground surfaces and, ultimately, affects the bed of the entire channel as well. According to the intensive research on the condition of the high-flow plain of the mouth of the Han River, the silt deposited in the high-flow plain was the main cause of settlement/growth of vegetation. And this leads to landforming along with woods-forming, disturbing flood control as well as the normal river ecology.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.165-169
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• 2010

The cityward tendency of the population caused the building crowd and the skyscrapers, and destroyed the cityscape and ecosystem of the city. For this reason, many researchers studied to make more green spaces in the city. The roof greening is one of the methods to get the green spaces in the city. There are some problems in this method such as the safety load, growth of the plants on the artificial foundation, and so on. In this study, we evaluated the waste woodchips and the waste papers as a new materials for the artificial foundation. The new artificial foundation was made of the waste woodchips and the waste papers with the different ratio of mixture (woodchips, paper slurry, and fertilizer). The artificial foundation was applied to the planting of three different plants (creeping bentgrass, barley, and wheat). It was found that the growth of the plants with 1% of fertilizer was higher than other conditions. The best making condition of foundation was 40% pulp and 60% woodchips in the germination of all plants.

• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.9-16
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• 2014

BACKGROUND: This study was conducted to investigate the effects of seeding timing and method of rye and/or hairy vetch on seasonal soil and foliar nutrient concentrations as well as fruit quality in a pesticide-free pear orchard. METHODS AND RESULTS: The treatments included as followed: single seeding of rye in September (Sep-Mono), November (Nov-Mono), and January (Jan-Mono), or mix seeding of rye+hairy vetch in November (Nov-Mix) and January (Jan-Mix), or sod culture as a control. Cover crops or vegetation was mown and mulched on the soil surface in April and May for two years. Nov-Mix treatment produced the highest dry matter weight of $12,070kg\;ha^{-1}$, with the lowest dry matter weight for sod culture ($6,520kg\;ha^{-1}$), following Jan-Mix ($7,030kg\;ha^{-1}$). Nov-Mix treatments increased potential amount of N, P, and K from the raw materials of the cover crops as well as improved soil physical properties. Nov-Mix treatments overall elevated soil pH, EC, organic matter, and $P_2O_5$ in May compared to other cover crop treatments or sod culture. The difference of the seasonal nutrient concentrations in leaves or fruit qualities were not consistently occurred amongst treatments. CONCLUSION: Nov-Mix treatments showed playing role in a substitute of a chemical fertilizer. Delayed seeding of cover crops such as Jan-Mix did not increase the potential dry matter production due to the short growing period, and the seeding time would affect the dry matter production of cover crops.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.817-820
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• 2008

The river environments of many streams in korea have been deteriorate through the rapid industrialization and urbanization since the 1960s. In korea, on the other hand, much efforts on the research and project have been made for the restoration of the deteriorated streams to close-to-nature. in order to restore the deteriorated streams, therefore, it is necessary to investigate such advanced technologies and materials. In view of this requirement, various research paths are being taken focusing on coarse aggregates to make multi-functional porous concrete having continuous voids so as to improve water and air permeability, acoustic absorption, water purification and applicability to vegetation. The Purpose of this study is to investigate the method for recovery of the environment in the streams area using porous concrete retaining wall block. the multi-P.O.C block applies for test in the Jangduri-cheon have been monitored planting, stability etc. after 6 months, plant grows flourishing and reconstructed in state such as nature rivers.

• Korean Journal of Environment and Ecology
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• v.23 no.4
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• pp.346-352
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• 2009

This study was conducted in order to provide as a basic materials of sea cliff vegetation structure through distribution related with the landform and growth pattern of mixed growth plants by ordination method in the Peucedanum japonicum community of Korea. The mixed growth plants of frequency over 10% growth with Peucedanum japonicum community of sea cliff was investigated as a total 26 species, and the frequency of appearing plants was the highest in the Aster spathulifolius(55.7%). Growing pattern of mixed growth plants was a difference by the landform factors as such the inland side, coastline side, flat and slope. Growing pattern was classified into typicality type, one-sided type and complex type. Growing pattern of the typicality type was good distribution in total landform factors, the one-sided type was good distribution in 1 landform factor and the complex type was good distribution in 2 landform factors. In growing pattern of mixed growth plants with Peucedanum japonicum, Artemisia capillaris and Sedum oryzifolium was typicality type, Elymus dahuricus and Artemisia princeps was one-sided type, and Aster spathulifolius, Miscanthus sinensis, Calystegia soldanella and Lysimachia mauritiana was complex type. In total plants of mixed growth, growing pattern of 16 species of 61.5% was good as complex type.

• Journal of Chest Surgery
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• v.44 no.5
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• pp.332-337
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• 2011

Background: The optimal timing of surgery for infective endocarditis complicated by embolic stroke is unclear. We compared early versus delayed surgery in these patients. Materials and Methods: Between 1992 and 2007, 56 consecutive patients underwent open cardiac surgery for the treatment of infective endocarditis complicated by acute septic embolic stroke, 34 within 2 weeks (early group) and 22 more than 2 weeks (delayed group) after the onset of stroke. Results: The mean age at time of surgery was $45.7{\pm}14.8$ years. Stroke was ischemic in 42 patients and hemorrhagic in 14. Patients in the early group were more likely to have highly mobile, large (>1 cm in diameter) vegetation and less likely to have hemorrhagic infarction than those in the delayed group. There were two (3.7%) intraoperative deaths, both in the early group and attributed to neurologic aggravation. Among the 54 survivors, 4 (7.1%), that is, 2 in each group, showed neurologic aggravation. During a median follow-up of 61.7 months (range, 0.4~170.4 months), there were 5 late deaths. Overall 5-year neurologic aggravation-free survival rates were $79.1{\pm}7.0%$ in the early group and $90.9{\pm}6.1%$ in the delayed group (p=0.113). Conclusion: Outcomes of early operation for infective endocarditis in stroke patients were similar to those of the conventional approach. Early surgical intervention may be preferable for patients at high risk of life-threatening septic embolism.

• Ecology and Resilient Infrastructure
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• v.6 no.3
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• pp.163-170
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• 2019

The civil engineering materials used to stabilize the slopes of new riverbanks have a great impact on the types and growth of vegetation introduced after the completion of construction procedure. Recently, microbial-derived, ${\beta}$-glucan- and xanthan gum-based biopolymers are attracting attention as an ecofriendly strengthening material of riverbanks that can possibly stimulate plant growth. This study aimed to assess ecological effects of biopolymer application on native plants in Korean riverbanks. In particular, since dominant plant species could shape characteristics of an ecosystem, we examined the effects of biopolymer on the dominant plant species in riverbanks. Overall, biopolymer did not affect seed germination rates of testing plant species. In contrast, plants grew more vigorously in the soil mixed with biopolymer compared to those in the control soil. The biomass of Echinochloa crus-galli especially increased around two times more in the biopolymer treatment. Plants produced heavier root biomass and leaves with larger specific leaf area, which possibly contributes to the tolerance of environmental stress like drought. These results suggest that biopolymers treated on river banks are expected to stimulate plant growth and increase stress tolerance of domestic dominant plant species.