• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.2
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• pp.131-142
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• 2023

Solar power facilities to reduce carbon emissions are continuously being installed in forests, farmland, city, and on water. However, research on visual preferences and the psychological impact on observers after installing solar power facilities is insufficient. Therefore, in this study, shooting was conducted according to the viewing distance of the near, middle, and distant views of Hapcheon Dam, Korea's largest floating photovoltaic power plant. The acquired images were edited using Photoshop to compare the presence or absence of floating photovoltaic power generation facilities. In addition, psychological changes and visual preferences were analyzed through an EEG test and questionnaire among 50 participants. The results are summarized, as follows. First, the installation of water photovoltaic power generation facilities has a passive impact on the subjects' psychological changes and visual preference. Second, the psychological changes due to the installation of water photovoltaic power generation facilities were judged to affect almost all research subjects, regardless of nationality, gender, or universisty major. Third, the visual preference for installing the water photovoltaic power generation facility is low, which can be interpreted as the water photovoltaic power generation facility negatively affecting the "friendliness" and "naturalness" of the landscape. In addition, this change in visual preference was found to differ depending on the gender and universiity major of the subjects. Fourth, the psychological change and visual preference of the floating photovoltaic power generation facility according to the viewing distance, found that the close range had a higher effect than the middle and distant ranges.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.384-392
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• 2022

The objective of this study was to estimated nitrogen content and chlorophyll using RGB, Hyperspectral sensors to diagnose of nitrogen nutrition in apple tree leaves. Spectral data were acquired through image processing after shooting with high resolution RGB and hyperspectral sensor for two-year-old 'Hongro/M.9' apple. Growth data measured chlorophyll and leaf nitrogen content (LNC) immediately after shooting. The growth model was developed by using regression analysis (simple, multi, partial least squared) with growth data (chlorophyll, LNC) and spectral data (SPAD meter, color vegetation index, wavelength). As a result, chlorophyll and LNC showed a statistically significant difference according to nitrogen fertilizer level regardless of date. Leaf color became pale as the nutrients in the leaf were transferred to the fruit as over time. RGB sensor showed a statistically significant difference at the red wavelength regardless of the date. Also hyperspectral sensor showed a spectral difference depend on nitrogen fertilizer level for non-visible wavelength than visible wavelength at June 10th and July 14th. The estimation model performance of chlorophyll, LNC showed Partial least squared regression using hyperspectral data better than Simple and multiple linear regression using RGB data (Chlorophyll R²: 81%, LNC: 81%). The reason is that hyperspectral sensor has a narrow Full Half at Width Maximum (FWHM) and broad wavelength range (400-1,000 nm), so it is thought that the spectral analysis of crop was possible due to stress cause by nitrogen deficiency. In future study, it is thought that it will contribute to development of high quality and stable fruit production technology by diagnosis model of physiology and pest for all growth stage of tree using hyperspectral imagery.

• Journal of Soil and Groundwater Environment
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• v.14 no.2
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• pp.45-53
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• 2009

A quick and simple detection method of explosive compounds in environmental matrix (soil and water) can provide a screening step which reduces the number of unnecessary samples and the cost of expensive laboratory analysis at a site investigation. A commercially available EXPRAY$^{(R)}$Explosives Field Detection Kit (EXPRAY) was used to determine the minimum detection concentration and to test the possibility of semi-quantitative analysis of 14 explosive compounds using standard solutions. The results showed that EXPRAY could detect 5 explosive compounds, TNT, RDX, HMX, Tetryl, and TNB, out of 14 US EPA designated explosives. The minimum detection limit of the nitramine explosives was 14 ng/$^2$ for HMX and RDX. EXPRAY was more sensitive to nitroaromatics than the nitramines and the minimum detection limits per unit area (mm$^2$) for Tetryl, TNB, and TNT, were 3 ng, 3 ng, and 0.3 ng, respectively. The semi-quantification of 5 explosive compounds in an order ofmagnitude could be achieved by the intensity of developed color only when EXPRAY was applied on the standard solutions under controlled laboratory conditions. With contaminated soil samples, however, only the presence and type of explosive compounds was identified. Therefore, EXPRAY is an economic and sensitive method that can be used in a screening step for the identification of explosives in the field samples.

• Korean Journal of Applied Biomechanics
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• v.18 no.2
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• pp.125-139
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• 2008

The purpose of this study is to compare and analyze a kinematic characteristics of throwing performance among born visually impaired, postnatal visually impaired and visually correct people through their kinematic characteristics. Another purpose of this study is to prevent injury and improve blind's exercise leadership and physical abilities. Three video cameras were used and each camera's shooting velocity was 60field/sec. Then the longest thrown pose was collected and analyzed by using Kwon 3D ver. 3.1 program. The results obtained from this study were followings; 1. During release, the fastest speed of ball was visually corrected followed by postnatal visually impaired and then born visually impaired. 2. Visually corrected used wrist joint well and had wide body round range with similar motion patterns, however born visually impaired couldn't do this at all. 3. Visually corrected used waist to lead shoulder at Phase 2 while throwing ball, but some of born visually impaired and postnatal visually impaired couldn't use waist to lead shoulder. 4. Visually corrected looked at the way where ball would go, but blinds couldn't look where ball would go. 5. Not like visually corrected who show similar patterns, born visually impaired showed each different patterns and some postnatal visually impaired showed similar patterns with visually corrected. 6. While throwing ball, visually corrected showed flexible weight-movement, postnatal visually impaired were not good as visually corrected, and born visually impaired couldn't do weight-movement at all. Synthetically, this result showed that throwing motions are affected a lot by the time when people became blind.

• Journal of Korean Society of Transportation
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• v.28 no.3
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• pp.51-57
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• 2010

In this study, damages due to the aircraft noise were examined in more than 190 elementary, middle and high schools near the airports in Korea, and the persecutory idea forecast model was established using the quantification theory type II. Via the survey of 1,012 teachers in the schools, a class interference forecast model was established, and the noise characteristics of five areas, four military/civil common-use airports and one shooting range, were examined. The following conclusions were made from the study. WECPNL values in the five military/civil common-use airports showed that all of them were Class 1 or 2 affected areas, which indicated that they had serious aircraft noise problems to be addressed. The most influential factor in the aircraft noise persecutory idea model was the distance between the airport and the school. It showed a positive relationship at a distance of less than 5 km, and a negative relationship at a distance of 10 km or more. The number and time of aircraft noise exposure as well as the types of airports and window structures had strong influences. The forecast model had a correlation ratio of 0.56, which indicates that it is highly appropriate. In the class interference factor analysis, the time and number of aircraft noise exposure were strong influential factors, and the results varied according to the service duration and sex of teachers. This model had a correlation ratio of 0.61, which indicates it is highly appropriate.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.1
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• pp.1-10
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• 1999

The north-west sea area of Cheju Island is where originate two layer current in the summer season. The case of the fishing operations in this sea area is almost impossible for normal expansion of the net gear for shooting net, and is happened to be frequent occasions for rise of tension suddenly in purseline by changes of the net shapes in the operation. Therefore, the safety of the operations is often obstructed by the above mentioned. In connection with the above, model experiments on the purse seine in the circulating water tank was carried out in comparison and analysis on the changes of tension in the pruseline by deformation of purse seine in the sea area of two layer current. THe results obtained are as follows;In the case of the required time for pursing of 20 minutes in the no current set, the increasing curve for tension of purseline can be expressed as:Y=0.0004x3+0.0098x2+0.3000x(r=0.9989)where Y is tension(metric tons) of a purseline, x is required time(minutes) for pursing. And, the maximum value of tension in this time was an increase of 31.3 percent at 15 minutes, and was a decrease of 30.3 percent at 30 minutes than that of 20 minutes.When the bottom margin of net is held on the position in velocity of 0.5 knot at three-eighths of net in the bottom current to the net height, the maximum tension of the required time for pursing of 30 minutes in tight set and loose set were decrease of 29.5 percent and 28.7 percent respectively than that of 20 minutes.The work load during the required time for pursing of 20 minutes were calculated 5.79×106 kgf·m in no current set, 7.89×106 kgf·m in tight set and 5.15×106 kgf·m in loose set, therefore it was an increase of 22.3 percent in tight set, and was a decrease of 11.1 percent in loose set than that of the no current set. Where tight set and loose set is a range of the bottom current with velocity of 0.5 knot at three-eighths of net to the net height.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.541-546
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• 2020

The surveillance radar for naval ships is an essential equipment of a battle system that executes the detection and tracking of targets, and the shooting support function; it calculates the three-dimensional track of the target range, azimuth, and altitude to carry out its duty. The surveillance radar consists of an antenna, a transceiver, a processing unit, and an air dryer section. The radar radiates the transmission signal on the antenna section, receives the reflected signal from the target, and amplifies the signals on the transceiver section. The signal received from the antenna is used to provide the operator with target information in various ways. This study identified the display problems when the information about the target is displayed through the radar. The causes of the problems were analyzed and improved. The tracking disappearance phenomenon caused by the altered-course of the ship was improved on the TWS tracking algorithm. The validity of the improved TWS tracking algorithm was confirmed by the normal condition of the target status on the B-scope.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.3
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• pp.259-274
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• 2017

Platycodon grandiflorum (Bell flower) is an important plant that has traditionally been used as herbal medicine for the treatment of cough, phlegm, sore throats, lung abscesses, chest pains, dysuria, and dysentery. The present study was initiated to investigate the feasibility of inducing shoot and root organogenesis in cultured explants of P. grandiflorum in a range of culture media and through use of various plant growth regulators (PGRs). The plantlets (Stem containing one node) were isolated and cultured on different concentrations of Murashige and Skoog (MS) medium supplemented with PGRs. We found that proliferation and elongation of shoots and roots could be achieved on 1/4 MS for P. grandiflorum with wild and green petals and on 1/8 MS for P. grandiflorum with double petals. The highest levels of development and elongation of adventitious shoots and roots were observed when petal explants were cultured on 1/4 MS (pH 3.8) supplemented with 5% sucrose. Increasing the agar concentration reduced shoot growth and rooting potential; nevertheless, the highest number of shoots and roots was observed on 0.6% agar. In the case of growth regulators, 1/4 MS supplemented with $1mg\;L^{-1}$ 6-benzylaminopurine (BA) was found to be best for shooting, although higher concentrations of BA tended to reduce shoot and root elongation. The highest number of shoots was achieved on $0.5mg{\cdot}L^{-1}$ thidiazuron (TDZ) from double petal explants grown on 1/8 MS. However, root and shoot elongation were found to decrease when TDZ concentrations were increased. Low concentrations of kinetin, naphthalene acetic acid, indole acetic acid, and 3-indole butyric acid induced shoot and root proliferation and elongation. Taken together, our study showed that low concentrations of PGRs induced the greatest root formation and elongation, showing that the optimal concentration of PGRs for shoot proliferation was species-dependent.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.6
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• pp.147-153
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• 2021

The purpose of this study is to establish strategic suggestions for the direction of the drone-related business by Gyeonggi-do through a survey on the operation and actual conditions of the drone geospatial information service business experienced by Gyeonggi-do civil servants. For this purpose, as a result of surveying the demand survey of 219 people in charge of drone field work, it was analyzed by dividing it into four categories: technology-based operation support, business discovery and support, legal and institutional support, and education and public relations. As an improvement measure, technology-based operation support is to secure service operation efficiency by establishing a dedicated manpower and a dedicated organization and securing drone-related experts.The plan for improvement of project discovery and support is as follows. 1) The government proactively discovers prior research projects for project discovery and support; 2) Legal and institutional support requires support services for simplification of administration such as drone geospatial data shooting schedules and permits, 3) legal and institutional review on improving the scope and restrictions for using drone geospatial data. In the field of education and publicity, it is necessary to operate an education program on the overall operation of drones, and to conduct seminars for each field and use, and to seek activation methods through practical application guidelines for the application process and system. The limitation of this study is that the survey subjects are related to Gyeonggi-do, and in the future, survey analysis through a wide range of participants is required.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.63-71
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• 2021

Recently, high-resolution cameras in smartphones enable measurement of minute objects such as cracks in concrete using image processing techniques. The technology to investigate the crack width using an application at an adjacent distance of the close shot range has already been implemented, but the use is limited, so it is necessary to verify the usability of the high-resolution smartphone camera to measure cracks at a longer distance. This study focuses on recognizing the size of subdivided crack widths at a thickness within 1.0 mm of crack width at a distance of 2 m. In recent Android-based smartphones, an experiment was conducted focusing on the relationship between the unit pixel size, which is a measurement component, and the shooting distance, depending on the camera resolution. As a result, it was possible to confirm the necessity of a smartphone lens for the classification and quantification of microcrack widths of 0.3 mm to 1mm. The universal telecentric lens for smartphones needed to be installed in an accurate position to minimize the effect of distortion. In addition, as a result of applying a 64 MP high-resolution smartphone camera and double magnification lens, the crack width could be calculated within 2 m in pixel units, and crack widths of 0.3, 0.5, and 1mm could be distinguished.