• FLOWER RESEARCH JOURNAL
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• v.26 no.4
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• pp.187-194
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• 2018

This study was conducted to investigate the facilities, cultivation, postharvest management, and distribution status of 27 cut chrysanthemum farms in Korea. The 60% of farms have cultivated the cut chrysanthemum using soil fertigation system in the PE plastic house. In Jeonnam and Busan provinces, Standard type of chrysanthemum was cultivated mainly than spray type of chrysanthemumJeoas. Most farms have been producing the rooted cuttings by plug system using cuttings self-propagated or purchased from the company, but farms in Jeonnam have been planting cuttings directly on cultivation bed. And the 66.6% of cut chrysanthemum farms have been pretreating with dipping in hot water or tap water after harvesting. Precooling was not performed on 70.4% of the farms, and precooling farms have been mainly conducted at temperature of $2-4^{\circ}C$. After harvesting, 70.4% of the farms stored the cut flowers at $2-4^{\circ}C$ for more than 48 hours to control the distribution volume. Cut chrysanthemum was graded mainly by individuals before distribution, and some export farmers have been conducting the cooperative grading. In distribution, all farms have distributed the cut flowers to the domestic markets, and 44.4% of these farms have been also exporting. The 63.0% of farms distributed to domestic market have been trading with flower auction sites.

• MARITIME LAW REVIEW
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• v.29 no.2
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• pp.115-144
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• 2017

The impact of the global financial crisis, which began in the United States in 2007, had a major impact on the domestic shipping and shipbuilding industries. In this regard, the domestic shipyard has established an order-taking strategy in several ways as an alternative to lowering the amount of construction of commercial vessels due to deterioration of the shipping industry, and selected industrial sector was the offshore plant sector. However, the domestic shipyard has under performed the offshore plant in order to just increase sales and secure work without any risk analysis for EPC contracts. As a result, the shipyard has been charged more than the initial contract price with the offshore plant contractor, or the shipyard has become a legal issue requiring payment of liquidated damages due to delays in delivery of the product. The main legal disputes are caused by the thorough risk analysis and the inexperience of process control that can occur during offshore plant construction. and In particular, there is no sufficient review of the unequivocal provisions in the contract as an element of risk management. There is no human resource to review these contractual clauses. Therefore, this study identifies the existence of specific risks that could lead to delays in offshore plant construction, and examined the existence of any unequivocal clauses in contracts for offshore plant construction. and also discussed how the toxic clause applies to the actual parties and how the concrete risk factors in the construction contracts are transferred and expressed by referring to the interviews with the project manager of the domestic shipyard and the previous research. As a result, This paper examined the legal liability of the contracting parties regarding delayed delivery of the products due to the offshore plant construction contract. And to improve the domestic shipbuilding industry.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.225-235
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• 2021

To attain the long-term benefits of forest restoration in North Korea, it is important to present the economic value of reforestation. This study as aimed to evaluate the economic value based on cost-benefit analysis from the ecosystem services perspective. The benefits of reforestation were classified into ecosystem services such as carbon sequestration, water supply, soil erosion control, and disaster risk reduction, and were converted into economic values to calculate comprehensive benefits. In the forest restoration scenario, an "independent forest restoration scenario (IFS)" and a "cooperation-based forest restoration scenario (CFS)" were composed in consideration of recent afforestation performance and forest policy, and the difference in the quantity of afforestation was derived as a scenario despite the same restoration period. In the IFS, it is estimated that over the next two decades, 800 thousand ha of the forest will be restored at a cost of KRW 3,829 billion, resulting in a benefit of KRW 6.87 trillion. The present benefit net value is KRW 3,39 trillion. In the CFS, it is estimated that the benefits of KRW 18,890 billion will be generated by restoring 2.2 million ha of the forest at a cost of KRW 10,053 billion. The present benefit net value is KRW 8,359 billion. In both scenarios, BCR had an economic feasibility value greater than 1, but there was a big difference in the expected benefits. In conclusion, forest restoration can have higher benefits than cost, and its value could be enhanced through forest cooperation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.111-118
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• 2020

The U-shaped composite beam used in this study consist of a reinforced concrete structure, a beam steel structure supporting the slab, a reinforced concrete structure, and a U-shaped steel plate. The U-shaped composite beam was developed for the purpose of using it as a parking lot because it is highly constructible and has low floor height and long span. For the improvement of constructivity, the U-shaped composite beam ends are planned with standardized H-shaped steel and connected directly to the columns, and the middle of the U-shaped composite beam consists of U-shaped steel plates folded in U-shaped form using thin steel plates (t=6) instead of H-shaped steel. In the middle of the composite beam, where U-shaped steel plates are located, the depth of U-shaped beam may be planned to be small so as to satisfy the height limit of the parking lot. It is important to grasp the structural performance according to the change of depth because low beam depth is advantageous for the reduction of the floor height, but it is a inhibitor to the structural behaviors of U-shaped composite beam. In addition, since U-shaped composite beams are a mixture of steel frame structures, reinforced concrete structures and U-shaped steel plates, securing unity has a great influence on securing structural performance. Therefore, in this study, a structural experiment was conducted to understand the structural performance according to the depth change for U-shaped composite beam. A total of three specimens were planned, including two specimens that changed the depth using a criteria specimen planned for a general parking lot. The results of the experiment showed that the specimens who planned the depth greatly had better structural performance such as yield strength, maximum strength, and energy than the standard specimen.

• The Journal of Engineering Geology
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• v.30 no.4
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• pp.515-523
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• 2020

If the safety factor does not secure the safety factor suggested in the design standard at the slope design stage, the safety factor is secured by installing an anchor. Stability analysis is used to verify the effect of reinforcing the slope of the anchor, but in this process, most of the anchor construction intervals are assumed to be equal and analyzed. For economical and effective slope reinforcement, stability analysis is required by adjusting the anchor construction interval. In this study, the effect of the anchor construction interval on the change of the safety factor of the slope was identified. Stability analysis was performed by setting a virtual slope with two berms and different anchor construction intervals. As a result of the analysis, the stability of the slope is secured when the anchor spacing of the lower surface is narrowed and the anchor gaps of the upper and middle surfaces are wider than when anchors are installed at the same intervals on the upper, middle, and lower surfaces of the slope. The result was a 15% reduction in the amount of anchors. This means that, rather than reinforcing anchors at the same intervals, it is economical and effective to have an economical and effective reinforcement effect to vary the anchor construction intervals according to the slope characteristics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.888-895
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• 2020

In the construction industry, off-site construction (OSC) is drawing attention as a production method due to changes in working hours and the supply and demand of manpower. In 1991, there was a policy of spreading and expanding the use of precast concrete (PC) apartment homes, but they have not been actively used so far since they were discontinued due to quality problems. In this study, policy tasks were analyzed to motivate the application of OSC-based PCs in the apartment housing sector, and policy directions were derived by conducting focus group interviews (FGI). Nine policies are suggested regarding the following topics: PC apartment supply quantity provision, priority application of public housing, priority supply of public housing, preferential floor area ratio, funding, tax support, improvement of business area structure, improvement of delivery method, factory certification system, and training of experts. The results of the FGIs are as follows. First, in order to revitalize PC apartment homes, leading efforts from the public sector are required. Second, rather than reorganizing the business sector or introducing a new delivery method, a policy direction that induces the strengthening of cooperation is desirable. Third, PC activation should be promoted on an institutional basis for securing appropriate construction costs and quality.

• Journal of the Korean Institute of Gas
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• v.24 no.6
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• pp.34-46
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• 2020

In order to supply stable natural gas in the future, it is necessary to forecast the demand in advance and secure the quantity of supply. In this paper, we propose a method of estimating the demand function of industrial natural gas, which is the core of the increase of domestic natural gas demand in the future. The cross-sectional data of 304 domestic industries were used to estimate the demand function of the industrial natural gas, and the effect of industry specific characteristics such as capital investment, manufacturing cost. Finally, the least absolute deviation estimation method which is robust to outliers and does not assume the homogeneity of the error term and the normality, And the results were derived. In addition, the economic value of industrial city gas was estimated using the price elasticity of industrial city gas. Therefore, it can be seen that the continuous expansion and supply of city gas to the industrial sector is beneficial at the national level, and the government needs to promote expansion through the industrial city gas support policy.

• Journal of Broadcast Engineering
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• v.27 no.3
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• pp.391-401
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• 2022

As deep learning-based object detection and recognition research have been developed recently, the scope of application to industry and real life is expanding. But deep learning-based systems in the construction system are still much less studied. Calculating materials in the construction system is still manual, so it is a reality that transactions of wrong volumn calculation are generated due to a lot of time required and difficulty in accurate accumulation. A fast and accurate automatic drawing recognition system is required to solve this problem. Therefore, we propose an AI-based automatic drawing recognition accumulation system that detects and recognizes steel materials in construction drawings. To accurately detect steel materials in construction drawings, we propose data augmentation techniques and spatial attention modules for improving small object detection performance based on YOLOv4. The detected steel material area is recognized by text, and the number of steel materials is integrated based on the predicted characters. Experimental results show that the proposed method increases the accuracy and precision by 1.8% and 16%, respectively, compared with the conventional YOLOv4. As for the proposed method, Precision performance was 0.938. The recall was 1. Average Precision AP_0.5 was 99.4% and AP_0.5:0.95 was 67%. Accuracy for character recognition obtained 99.9.% by configuring and learning a suitable dataset that contains fonts used in construction drawings compared to the 75.6% using the existing dataset. The average time required per image was 0.013 seconds in the detection, 0.65 seconds in character recognition, and 0.16 seconds in the accumulation, resulting in 0.84 seconds.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.4
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• pp.193-198
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• 2021

Recently, interests in the 4th industry have increased the level of demand for pest control by farmers in the field of rice farming, and the interests and use of agricultural pest control drones. Therefore, the diversification of agricultural control drones that spray high-concentration pesticides and the increase of agricultural exterminators due to the acquisition of national drone certifications are rapidly developing the agricultural sector in the drone industry. In addition, as detailed projects, an effective platform is required to construct large-scale big data due to pesticide management, exterminator management, precise spraying, pest control work volume classification, settlement, soil management, prediction and monitoring of damages by pests, etc. and to process the data. However, studies in South Korea and other countries on development of models and programs to integrate and process the big data such as data analysis algorithms, image analysis algorithms, growth management algorithms, AI algorithms, etc. are insufficient. This paper proposed an online drone pest control management information platform to meet the needs of managers and farmers in the agricultural field and to realize precise AI pest control based on the agricultural drone pest control processor using drones and presented foundation for development of a comprehensive management system through empirical experiments.

• Journal of Bio-Environment Control
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• v.31 no.2
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• pp.125-132
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• 2022

This study aimed to examine cucumber (Cucumis sativus) varieties adaptive to the desert climate by comparing and analyzing the growth, yield, and water consumption. Two long-sized cucumber varieties, 'Gulfstream' and 'Imea' and two medium-sized cucumbers, 'Nagene' and 'Sausan' were cultivated in coir substrate hydroponics under hot and humid greenhouse conditions from March 2 to June 20, 2020. On the 113 DAT, 'Nagene' had the longest plant height and the highest internode number. The marketable fruit number per plant was higher in the medium-sized varieties, which had more internode number. The marketable fruit number was 31.3 for 'Gulfstream', 30.7 for 'Imea', 57.8 for 'Nagene', or 56.0 for 'Sausan' with no significant difference in total fruit weights per plant. The water consumption required to produce 200 g of fruit was lower in the 'Nagene' (2.39 L) with the highest water use efficiency (WUE). Therefore, 'Nagene' variety may have higher adaptability to desert high temperature compared to the long-sized varieties, and it is going to be necessary to verify more medium-sized cucumber varieties.