• Journal of The Korean Society of Agricultural Engineers
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• v.62 no.4
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• pp.1-12
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• 2020

The extreme 2017 spring drought affected a large portion of South Korea in the Southern Gyeonggi-do and Chungcheongnam-do districts. This drought event was one of the climatologically driest spring seasons over the 1961-2016 period of record. It was characterized by exceptionally low reservoir water levels, with the average water level being 36% lower over most of western South Korea. In this study, we consider drought response methods to alleviate the shortage of agricultural water in times of drought. It could be to store water from a stream into a reservoir. There is a cyclical method for reusing water supplied from a reservoir into streams through drainage. We intended to present a decision-making plan for water supply based on the calculation of the quantity of water supply and leakage. We compared the rainfall-runoff equation with the TANK model, which is a long-term run-off model. Estimations of reservoir inflow during non-irrigation seasons applied to the Madun, Daesa, and Pungjeon reservoirs. We applied the run-off flow to the last 30 years of rainfall data to estimate reservoir storage. We calculated the available water in the river during the non-irrigation season. The daily average inflow from 2003 to 2018 was calculated from October to April. Simulation results show that an average of 67,000 tons of water is obtained during the non-irrigation season. The report shows that about 53,000 tons of water are available except during the winter season from December to February. The Madun Reservoir began in early October with a 10 percent storage rate. In the starting ratio, a simulated rate of 4 K, 6 K, and 8 K tons is predicted to be 44%, 50%, and 60%. We can estimate the amount of water needed and the timing of water pump operations during the non-irrigation season that focuses on fresh water reservoirs and improve decision making for efficient water supplies.

• Journal of the Korean Geotechnical Society
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• v.27 no.1
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• pp.17-24
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• 2011

The characteristics of flow and strength of CLSM depend on the combination ratio including the fly ash, pond ash, cement, water quantity and etc. However, it is very difficult to draw the mechanism about the flow, strength and the mixing ratio of each components. Therefore, the method of calculation drawing the flow about the component ratio of CLSM and compression strength value is needed for the valid practical use of CLSM. To verify the efficiency of artificial neural network, new data which were not used for establishing the model were predicted and compared with the results of laboratory tests. In this research, it was used to evaluate the learning efficiency of the artificial neural network model and the prediction ability by changing the node number of hidden layer, learning rate, momentum, target system error and hidden layer. By using the results, the optimized artificial neural network model which is suitable for a flow and compressive strength estimate of CLSM was determined.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.203-208
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• 2015

To identify the effect of fallen cherry blossom on the artificial pond ecosystem, microcosm experiment was conducted into the aquatic decomposition of Prunus species petals. Petals were put in $1mm^2$ mesh nylon litter bags. For treatment group, one flower litter bag was placed into each pot microcosm ($27{\times}20{\times}8cm^3$) filled with influent water from the artificial pond, whereas control group microcosm contained pond water only. Decomposition time were set differently (4, 8, 12, 16 days) among treatment groups. At the end of experiment, most petals were decomposed and only 32.3% of initial dry weight remained with the decay rate (k) of $7.06{\times}10^{-2}day^{-1}$. $NO_3-N$ concentration of microcosm water decreased sharply from 1.90 mg/L at first to 0.02 mg/L, whereas $NH_4-N$ concentration increased from 0.03 mg/L to 2.85 mg/L continually. $PO_4-P$ concentration was 0.03 mg/L at first and increased to 2.39 mg/L by decomposition. Therefore, available phosphorus seems to have leached with higher rate than nitrogen from the petals litter. Increase about 0.02 mg/L in $PO_4-P$ concentration could be estimated in artificial pond from the calculation on the total quantity of fallen blossoms. This result suggests that available phosphorus from the decomposed Prunus petals could cause eutrophication in the artificial pond.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.621-626
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• 2021

In this study, data on the study site for apartment construction was acquired, and the quantity of construction waste was calculated using a drone and mobile 3D laser scanner. The accuracy of the drone was 0.034 to 0.064m in the horizontal and vertical directions, respectively, and the mobile 3D Laser Scanner showed an accuracy of 0.018 to 0.049m in the horizontal direction, respectively. These results suggest that it is possible to construct spatial information using a drone and mobile 3D laser scanner with a value within the allowable accuracy of 1:1,000 digital terrain. The volume of construction waste calculated using the mobile 3D laser scanner data was 70,797㎥. It was possible to calculate the volume on the side of the building or some facilities that appeared as shaded areas in the drone outcomes. In addition, modeling was performed for view analysis of the apartments scheduled to be constructed and the terrain-based modeling results of the surrounding buildings. In the future, data construction and accuracy evaluation using mobile 3D laser scanners will be conducted. In addition, additional research comparing existing methods and work processes will be carried out, and the efficiency of mobile 3D laser scanners in the field of spatial information construction can be presented.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.200-210
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• 2020

The maintenance of educational facilities was assembled in 12 project classifications of the Educational Improvement Program. The priorities were decided by the evaluation scores derived from the condition investigation, and maintenance works were budgeted in the order of priorities. These priorities were a schedule for conducting maintenance and an important criterion for obtaining a construction order. Several restrictions in the condition investigation exist, which derives budgets and conducts maintenance separately based on the priorities. An educational facility manager has a restriction in quantity take-off, which results in an incorrect budget. Discomfort would occur in an educational environment, and a period of infringing safety would increase. This study proposes applying a BIM in the condition investigation and the planning framework for work-type packaging. A BIM supports a budget calculation and derives evaluation scores by linking a repair and an inspection result. The work-type packaging algorithm divides a budget allocation range and derives the result of a grouped work-types applied in an equivalent space and element. As a result of applying cases, it could shorten the duration by approximately 37.4%. Its usability in selecting a grouped work-type was evaluated through an assessment with workers.

• Korean Journal of Construction Engineering and Management
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• v.23 no.5
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• pp.65-76
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• 2022

The New Excellent Technology (NET) designation system, introduced in 1989 for the purpose of promoting the development of domestic construction technology and enhancing national competitiveness, reviews the statement of construction cost of new technologies. And the cost reduction effect such as design, construction, and maintenance cost and the effect of reducing the construction duration are evaluated as an evaluation criteria of economic feasibility. However, in this evaluation process, differences of opinion between the institution of construction cost estimating standard management and the new technology developer about unique technologies frequently occur. In addition it is difficult to objectively compare the construction duration with existing similar technologies because there is no information on productivity as the current cost estimating standards for new technologies only present the required amount per unit quantity. In this study, the current state of cost estimating criteria review procedure, evaluation criteria, and cost estimating standards establishment method were analyzed when screening for the designation of a new construction technologies, and compared with overseas cost estimating standards, measures to improve the cost estimating standards of current construction new technologies were suggested. Through the improved cost estimating standards of this study, it is expected that cost information on new technologies will be provided to clients in more detail than the current ones, and the availability and applicability of new construction technologies would be improved by simplifying the construction cost calculation process more.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1249-1249
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• 2022

The facade, an exterior material of a building, is one of the crucial factors that determine its morphological identity and its functional levels, such as energy performance, earthquake and fire resistance. However, regardless of the type of exterior materials, huge property and human casualties are continuing due to frequent exterior materials dropout accidents. The quality of the building envelope depends on the detailed design and is closely related to the back frames that support the exterior material. Detailed design means the creation of a shop drawing, which is the stage of developing the basic design to a level where construction is possible by specifying the exact necessary details. However, due to chronic problems in the construction industry, such as reducing working hours and the lack of design personnel, detailed design is not being appropriately implemented. Considering these characteristics, it is necessary to develop the detailed design process of exterior materials and works based on the domain-expert knowledge of the construction industry using artificial intelligence (AI). Therefore, this study aims to establish a detailed design automation algorithm for AI-based condition-responsive exterior wall panels and their back frames. The scope of the study is limited to "detailed design" performed based on the working drawings during the exterior work process and "stone panels" among exterior materials. First, working-level data on stone works is collected to analyze the existing detailed design process. After that, design parameters are derived by analyzing factors that affect the design of the building's exterior wall and back frames, such as structure, floor height, wind load, lift limit, and transportation elements. The relational expression between the derived parameters is derived, and it is algorithmized to implement a rule-based AI design. These algorithms can be applied to detailed designs based on 3D BIM to automatically calculate quantity and unit price. The next goal is to derive the iterative elements that occur in the process and implement a robotic process automation (RPA)-based system to link the entire "Detailed design-Quality calculation-Order process." This study is significant because it expands the design automation research, which has been rather limited to basic and implemented design, to the detailed design area at the beginning of the construction execution and increases the productivity by using AI. In addition, it can help fundamentally improve the working environment of the construction industry through the development of direct and applicable technologies to practice.

• Journal of Advanced Information Technology and Convergence
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• v.9 no.1
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• pp.115-125
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• 2019

In this paper, the image is received from the camera and the lane is sensed. There are various ways to detect lanes. Generally, the method of detecting edges uses a lot of the Sobel edge detection and the Canny edge detection. The minimum use of multiplication and division is used when designing for the hardware configuration. The images are tested using a black box image mounted on the vehicle. Because the top of the image of the used the black box is mostly background, the calculation process is excluded. Also, to speed up, YCbCr is calculated from the image and only the data for the desired color, white and yellow lane, is obtained to detect the lane. The median filter is used to remove noise from images. Intermediate filters excel at noise rejection, but they generally take a long time to compare all values. In this paper, by using addition, the time can be shortened by obtaining and using the result value of the median filter. In case of the Sobel edge detection, the speed is faster and noise sensitive compared to the Canny edge detection. These shortcomings are constructed using complementary algorithms. It also organizes and processes data into parallel processing pipelines. To reduce the size of memory, the system does not use memory to store all data at each step, but stores it using four line buffers. Three line buffers perform mask operations, and one line buffer stores new data at the same time as the operation. Through this work, memory can use six times faster the processing speed and about 33% greater quantity than other methods presented in this paper. The target operating frequency is designed so that the system operates at 50MHz. It is possible to use 2157fps for the images of 640by360 size based on the target operating frequency, 540fps for the HD images and 240fps for the Full HD images, which can be used for most images with 30fps as well as 60fps for the images with 60fps. The maximum operating frequency can be used for larger amounts of the frame processing.

• The Journal of the Convergence on Culture Technology
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• v.10 no.2
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• pp.499-503
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• 2024

Broadcasting programs are provided to various media such as Internet replay, OTT, and IPTV services as well as self-broadcasting. In this case, it is very important to provide keywords for search that represent the characteristics of the content well. Broadcasters mainly use the method of manually entering key keywords in the production process and the archive process. This method is insufficient in terms of quantity to secure core metadata, and also reveals limitations in recommending and using content in other media services. This study supports securing a large number of metadata by utilizing closed caption data pre-archived through the DTV closed captioning server developed in EBS. First, core metadata was automatically extracted by applying Google's natural language AI technology. The next step is to propose a method of finding core metadata by reflecting priorities and content characteristics as core research contents. As a technology to obtain differentiated metadata weights, the importance was classified by applying the TF-IDF calculation method. Successful weight data were obtained as a result of the experiment. The string metadata obtained by this study, when combined with future string similarity measurement studies, becomes the basis for securing sophisticated content recommendation metadata from content services provided to other media.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1195-1206
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• 2011

This study was conducted to apply LCA (Life cycle assessment) methodology to lettuce (Lactuca sativa L.) production systems in Namyang-ju as a case study. Five lettuce growing farms with three different farming systems (two farms with organic farming system, one farm with a system without agricultural chemicals and two farms with conventional farming system) were selected at Namyangju city of Gyeonggi-province in Korea. The input data for LCA were collected by interviewing with the farmers. The system boundary was set at a cropping season without heating and cooling system for reducing uncertainties in data collection and calculation. Sensitivity analysis was carried out to find out the effect of type and amount of fertilizer and energy use on GHG (Greenhouse Gas) emission. The results of establishing GTG (Gate-to-Gate) inventory revealed that the quantity of fertilizer and energy input had the largest value in producing 1 kg lettuce, the amount of pesticide input the smallest. The amount of electricity input was the largest in all farms except farm 1 which purchased seedlings from outside. The quantity of direct field emission of $CO_2$, $CH_4$ and $N_2O$ from farm 1 to farm 5 were 6.79E-03 (farm 1), 8.10E-03 (farm 2), 1.82E-02 (farm 3), 7.51E-02 (farm 4) and 1.61E-02 (farm 5) kg $kg^{-1}$ lettuce, respectively. According to the result of LCI analysis focused on GHG, it was observed that $CO_2$ emission was 2.92E-01 (farm 1), 3.76E-01 (farm 2), 4.11E-01 (farm 3), 9.40E-01 (farm 4) and $5.37E-01kg\;CO_2\;kg^{-1}\;lettuce$ (farm 5), respectively. Carbon dioxide contribute to the most GHG emission. Carbon dioxide was mainly emitted in the process of energy production, which occupied 67~91% of $CO_2$ emission from every production process from 5 farms. Due to higher proportion of $CO_2$ emission from production of compound fertilizer in conventional crop system, conventional crop system had lower proportion of $CO_2$ emission from energy production than organic crop system did. With increasing inorganic fertilizer input, the process of lettuce cultivation covered higher proportion in $N_2O$ emission. Therefore, farms 1 and 2 covered 87% of total $N_2O$ emission; and farm 3 covered 64%. The carbon footprints from farm 1 to farm 5 were 3.40E-01 (farm 1), 4.31E-01 (farm 2), 5.32E-01 (farm 3), 1.08E+00 (farm 4) and 6.14E-01 (farm 5) kg $CO_2$-eq. $kg^{-1}$ lettuce, respectively. Results of sensitivity analysis revealed the soybean meal was the most sensitive among 4 types of fertilizer. The value of compound fertilizer was the least sensitive among every fertilizer imput. Electricity showed the largest sensitivity on $CO_2$ emission. However, the value of $N_2O$ variation was almost zero.