• Journal of Ocean Engineering and Technology
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• v.9 no.2
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• pp.61-70
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• 1995

The purpose of this paper is to calculate the excavation volume of unequal interval grid using nonlinear boundary in eathwork volume determination for reclamation of the foreshore. A congruence area formula by first and third equation is compared with trapezoidal, simpson formulas to earthwork volume. And nonlinear spot level method of unequal interval grid is compared with linear and nonlinear spot level method of equal interval grid excavation volume. As a result algorithm of derived area and volume formula should provide a better accuracy than linear and nonlinear spot level currently in use. Practical application of each method to the excavation volume is illustrated by digital elevation model of aerial photogrammetry and model test of aquarium.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.8
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• pp.688-693
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• 2007

To improve aerodynamic efficiency of the Smart Un-manned Aerial Vehicle(SUAV), vortex generator was applied along the wing upper surface during SUAV tests. Vortex generator, initially used in TR-S2 configuration to enhance lift characteristic, increased lift coefficient. Meanwhile vortex generator produced excessive drag and eventually reduced lift-to-drag ratio. To examine the effect of vortex generator's height, three different heights of vortex generator were used for various SUAV configuration. Vortex generator of 3mm height used in TR-S4 configuration produced 3.1% increase in maximum lift coefficient and 1.5% reduction in lift-to-drag ratio.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.37-40
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• 2006

Wind tunnel testings to develope tilt-rotor Smart Unmanned Aerial Vehicle (SUAV) were intensively performed. Small wind tunnel was used to find and evaluate design parameters and to fix general layout of configuration. The application of large tunnel with 40% scaled model is to collect performance and stability related aerodynamic data. During large scale model test wind tunnel is used as a tool to compare Flaperon types, to improve lift characteristics by using different height vortex generators and to alleviate nacelle separated flow effects on the wing.

• Asian Journal of Turfgrass Science
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• v.8 no.3
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• pp.193-199
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• 1994

Effect pf rape seed oil cake compast (OM) active carbon(C) compound fertilizer (NPK) and magnesium sulfate (Mg) application on Zoysia koreana growth by lysimeter of 50cm soil column filled with a low fertility loam. Effect on growth was in order of OM>OM . NPK interaction> NPK . active carbon and Mg were not effective OM . NPK interaction effect was negative on leaf width and root dry matter yield. OM and OM . NPK interaction were most effective on rhizome growth. Their effect did not change the ratio of growth rates between aerial part and rhizome but change that between aerial part and root. Leaf width was most sensitive to the treatments.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.2941-2943
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• 1999

The application of the aerial images are to find the 3-D elevations. Image matching techniques such as Multi-resolution techniques, WCC (Weighted Cross-Correlation), NSSR (Narrow Search Sub-pixel Registration) that we know robustly apply to images which have enough features. But the method is not adaptive in images which have not enough features due to increasing of disparity errors. In this paper, we propose Disparity Interpolation that decrease disparity errors occurring in the area where images have not enough features. By using real aerial images we compare the result from existing image matching techniques to the result from proposed method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.145-150
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• 2006

The paper deals with integrated navigation and sense & avoid systems for small unmanned aerial vehicles (UAV). First an introduction to the current UAV activities of the institute is given. It is followed by an overview about the integrated navigation system developed for small UAVs. The system is based on a tightly-coupled GPS/INS architecture. But instead of using delta-ranges, time-differenced carrier phases are used to aid the INS. Finally, results from navigation filter validation in flight tests are presented. After that an overview about sense and avoid strategies for application in small unmanned aircraft is given. From this a guideline for developing such a system for the institute's UAVs is presented.

• Korean Journal of Medicinal Crop Science
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• v.23 no.4
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• pp.277-283
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• 2015

This study was conducted to investigate the selected chemical properties of soils in Saururus chinensis Baill (Chinese lizard's tail) cultivation fields to provide optimal fertilizer application rates and to examine the growth and pharmaco-consitituents of Saururus chinensis Baill as influenced by different amounts of nitrogen (N) fertilizer applications. Based on the results of selected soil chemical properties in 37 cultivation sites of the plant, soil pH, organic matter content, and exchangeable $K^{+}$ concentration were lower than optimal values for cultivating general medicinal crops even though relatively high standard deviations were found in some of the values. At the harvesting stage of the plant aerial parts, soil pH, electrical conductivity (EC), available $P_2O_5$, and exchangeable $Ca^{2+}$, $Mg^{2+}$, $Na^{+}$ decreased as comparing with those before transplanting the plant, whereas the concentration of exchangeable $K^{+}$ increased in the plot treated with N 100% and compost. Fresh weight of the plant aerial parts were highest, 492.5kg/10, in the N 100% treatment plot. Correlation equation between N levels treated (X) and yield of the plant aerial parts (Y) presented as $Y=-2.1609X^2+30.082X+344.12$($R^2= 0.7113$) and the optimal rate of N fertilizer application for the plant was 6.6kg/10a. Carbon concentrations in the plant were not different among the different N levels applied. N and K concentrations in the plant were highest in the plot of N 100% with compost applications, the highest P concentration was in N 100% plot, and the highest Ca and S concentrations were in N 200% plot. Quercetin and quercitrin were highest in the N 150% plot and tannin was highest in N 100% or N 100% with compost application plot.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.71-91
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• 2018

In recent years, application of UAV(Unmanned Aerial Vehicle) to seed sowing and pest control has been actively carried out in the field of agriculture. In this study, UAS(Unmanned Aerial System) is constructed by combining image sensor of various wavelength band and SfM((Structure from Motion) based image analysis technique in UAV. Utilization of UAS based vegetation survey was investigated and the applicability of precision farming was examined. For this purposes, a UAS consisting of a combination of a VIS_RGB(Visible Red, Green, and Blue) image sensor, a modified BG_NIR(Blue Green_Near Infrared Red) image sensor, and a TIR(Thermal Infrared Red) sensor with a wide bandwidth of $7.5{\mu}m$ to $13.5{\mu}m$ was constructed for a low cost UAV. In addition, a total of ten vegetation indices were selected to investigate the chlorophyll, nitrogen and water contents of plants with visible, near infrared, and infrared wavelength's image sensors. The images of each wavelength band for the test area were analyzed and the correlation between the distribution of vegetation index and the vegetation index were compared with status of the previously surveyed vegetation and ground cover. The ability to perform vegetation state detection using images obtained by mounting multiple image sensors on low cost UAV was investigated. As the utility of UAS equipped with VIS_RGB, BG_NIR and TIR image sensors on the low cost UAV has proven to be more economical and efficient than previous vegetation survey methods that depend on satellites and aerial images, is expected to be used in areas such as precision agriculture, water and forest research.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.1
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• pp.9-17
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• 2022

Rural spaces are increasingly valuable as areas for introducing renewable energy infrastructure to achieve carbon neutrality. Rural areas are the living grounds of rural residents, and the balance of conservation and development for rural areas is important for the introduction of reasonable facilities. In order to maintain a balance between development and preservation and to introduce reasonable renewable energy facilities, it is necessary to develop a current status survey and an effective survey method to utilize a space capable of introducing renewable energy facilities such as idle land and vacant houses. Therefore, this study was conducted to verify the readability using an unmanned aerial vehicle, and the main results are as follows. The detection of photovoltaic power generation facilities using unmanned aerial vehicles was effective in analyzing the location and area of photovoltaic panels located on the roofs of buildings, and it was possible to calculate the expected power generation by region through the area calculation of photovoltaic panels. The vacant house detection can be used to select an investigation target for an vacant house condition survey as it can identify damage to buildings that are expected to be empty houses, management status, and electricity supply facilities through aerial photos. It is judged that the unmanned aerial vehicle detection capability can be utilized as a method to improve the efficiency of investigation and supplement the data related to solar power generation facilities and vacant houses provided by public institutions. Although this study detected the status of solar power generation facilities and vacant houses through high-resolution aerial image analysis, as a follow-up study, automatic measurement methods using the temperature difference of solar power generation facilities and general characteristics of vacant houses that can be read from the air were investigated. If the deriving research is carried out, it is judged that it will be possible to contribute to the improvement of the accuracy of the detection result using the unmanned aerial vehicle and the expansion of the application range.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.307-314
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• 2011

This study proposed detection method of Marine debris using unmanned aerial photography. For unmanned aerial photography, a RC(Radio Control) helicopter which has good movability and economics was used. To a camera mounting, a gimbal equipment was attached to the bottom of the RC helicopter. The gimbal equipment is very useful because it is not seriously affected by vibration and rolling. In addition, we invented that digital image processing algorithm using Matlab program for detection of marine debris from photographs. Particularly, background subtraction in invented algorithm was applied. As a result, marine debris of a variety of forms from different sand states of coast were reliably detected. In the future, monitoring using proposed method was expected to contribute that the solution to representative problem of monitoring area selecting and estimate the total litter mass over the beach. Moreover, It is considered a greater application possibility to marine environmental observations.