• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.5 s.51
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• pp.25-33
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• 2006

This paper provides a method to predict the ductile capacity of reinforced concrete beam-column joints that fail in shear after the plastic hinges occur at both ends of the adjacent beams. After the plastic hinges occur at both ends of the beams, the longitudinal axial strain at the center of the beam section in the plastic hinge region abruptly increases because the neutral axis continues to move upward toward the extreme compressive fiber and the residual strain of the longitudinal bars continues to increase with each cycle of inelastic loading. An increase in the axial strain of the beam section after flexural yielding widens the cracks in the beam-column joints, thus leading to an decrease of the shear strength of the beam-column joints. The proposed method takes into account shear strength deterioration in the beam-column joints. In order to verify the shear strength and the corresponding ductility of the proposed method, test results of 52 RC beam-column assembles were compared. Comparisons between the observed and calculated shear strengths and their corresponding ductilities of the tested assembles, showed reasonable agreement.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.5
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• pp.527-535
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• 2009

This paper describes the control system to suppress the load pendulation using tagline for the floating crane. Dynamic equation of motion of the floating crane and the load is derived using Newton's 2nd law and free body model. The floating crane and the load are assumed that they move in center plane. Each rigid body has 3 DOF (surge, heave, pitch), because it moves in two directions and rotates. Then, this system, which is composed of two rigid bodies, has 6 DOF. The gravitational force, the hydrostatic force, the hydrodynamic force and the tension of the wire rope are considered as external forces, which affect to the floating crane. To suppress the pendulation of the load, the tagline, which connects between the load and the float crane, is applied to the system. The tagline is composed of the spring and the wire rope. Proportional and Derivative control is used as a linear control algorithm. The results of the numerical analysis of the 3,600 ton floating crane show that the tagline system is effective to suppress the load pendulation.

• Journal of Korean Academy of Nursing
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• v.42 no.3
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• pp.377-384
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• 2012

Purpose: This study was done to investigate factors affecting preparation stage to quit smoking in men. Methods: Based on data from the Community Health Survey conducted in Chungbuk Province in 2008, we estimated rates and odds ratio (OR) of smoking cessation intention for 2,639 men who were current smokers. Multivariate logistic regression analyses were used to identify factors affecting preparation stage to quit smoking. Results: Among current male smokers, the rate of smoking cessation intention was 17.1%. The OR of factors affecting smoking cessation was as follows: Compared to men with middle school education, the OR for rate of smoking cessation intention in men with high school education was 1.47 (p=.018), and for college or higher, 1.55 (p=.017). Compared to being single, the OR for cohabitation after marriage was 1.61 (p=.011) and living alone after marriage, 2.23 (p=.005). The OR for attempt to quit smoking, exposure to secondhand smoke and participation in smoking education were 6.80 (p<.001), 1.32 (p=.020) and 1.69 (p=.005), respectively. Conclusion: Results of this study show that it is necessary to decrease exposure to secondhand smoke and to increase participation in smoking cessation education targeting current smokers to move them from precontemplation or contemplation stage to preparation stage.

• Journal of Environmental Policy
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• v.10 no.3
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• pp.73-91
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• 2011

The fisheries in East Asia are reviewed in conjunction with climate change and social-economic developments in the 20th century. About one third of the human population resides in this region, producing a large share of the world's fisheries products, consuming them, and contributing significantly to the international trade of the products. Ongoing local and global climate changes, as well as ocean warming and acidification, are anticipated to have significant impacts on fisheries. Frequent typhoons have brought untold calamities and miseries to coastal communities. The rate of environmental change is outpacing our ability to respond effectively. The science must now move beyond identifying issues and toward providing sound bases for the development of innovative solutions, including effective adaptation and mitigation strategies. Fisheries management plans must be made to consider both changes in climate and social systems. It seems logical that an international forum should be made available to coordinate scientific research, management, and conservation of the region's fishery resources.

• Research in Plant Disease
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• v.26 no.3
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• pp.121-133
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• 2020

Climate change, increased extreme weather and climate events, and rapidly changing socio-economic environment threaten agriculture and thus food security of our society. Therefore, it is urgent to shift from conventional farming to smart agriculture using big data and artificial intelligence to secure sustainable growth. In order to efficiently manage plant diseases through smart agriculture, agricultural big data that can be utilized with various advanced technologies must be secured first. In this review, we will first learn about agrometeorological big data consisted of meteorological, environmental, and agricultural data that the plant pathology communities can contribute for smart plant disease management. We will then present each sequential components of the smart plant disease management, which are prediction, monitoring and diagnosis, control, prevention and risk management of plant diseases. This review will give us an appraisal of where we are at the moment, what has been prepared so far, what is lacking, and how to move forward for the preparation of smart plant disease management.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.141-150
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• 2012

This study aims to provide the basic biomechanical data on the average, maximum and distribution of plantar pressure during hockey penalty stroke by comparing five skilled and five unskilled players. Following are the conclusions. First in the case of average and maximum planter pressure during penalty stroke, the skilled players showed higher pressures at the moment of left foot landing in rear plantar of left foot and fore, rear plantar of right foot compared to the unskilled players. Also at the moment of impact, the skilled players showed higher pressures in fore, rear plantar of left foot and fore plantar of right foot compared to the unskilled. The analysis drew the conclusion that the skilled players move their center of body from fore, rear plantar of right foot to fore, rear plantar of left foot at the moment of left foot landing and impact in order to perform a quick and strong shooting. Second in the case of plantar distribution, as the skilled players put over 70% of their weights on left foot, they showed overall higher plantar pressure distributed on the outer fore, mid and rear parts of left foot plantar, in contrast with the unskilled players who showed about 50/50 distribution of weights on their right and left foot. The analysis concluded that such distribution was shown because the skilled players transferred their weights from the right to left foot effectively while the unskilled players could not do so.

• Journal of Ocean Engineering and Technology
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• v.28 no.1
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• pp.28-33
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• 2014

The Korean icebreaking research vessel "Araon" performed four sea trials in the Arctic and Antarctic Seas. The ice properties, such as the ice thickness, floe size, ice strength, and power of the vessel were quite different in these trials. To compare the speeds of ship with the same ice strength and power, the AARC (Arker Arctic Research Center) method is used with a vessel power of 10 MW and an ice strength of 630 Pa in this paper. Based on the analysis results, the speed of the ship was 1.62 knots (0.83 m/s) with a 1.02-m ice thickness and 2.5-km floe size, 5.3 knots (2.73 m/s) with a 1.2-m ice thickness and 1.0-km floe size, and 13.8 knots (7.10 m/s) with a 1.1-m ice thickness and 200-m floe size. The analysis results showed that the ship speed and floe size have an inversely proportional relationship. Two reasonable reasons are given in this paper for the final result. One is an ice breaking phenomenon, and the other is the effect of the ice floe mass. For the breaking phenomenon, the ice breaking force is very small because the ice floe is not breaking but tearing when a ship is passing through a small ice floe. Regarding the effect of the ice floe mass, it is impossible for a ship to push and tear an ice floe if the mass of the ice floe is too large compared to the mass of the ship. The velocity of the ship decreases when the ice floe has a large mass and a large size because the ship has to break the ice floe to move forward.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.3
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• pp.233-242
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• 2015

This paper analyzes a multi-product inbound lot-sizing and outbound dispatching problem with multi-vehicle types in a third-party logistics distribution center. The product must be delivered to the customers within the delivery time window and backlogging is not allowed. Replenishing orders are shipped by several types of vehicles with two types of the freight costs, i.e., uniform and decreasing, are considered. The objective of this study is to determine the lot-size and dispatching schedules to minimize the total cost with the sum of inbound and outbound transportation and inventory costs over the entire time horizon. In this study, we mathematically derive a mixed-integer programming model and propose a genetic algorithm (GA1) based on a local search heuristic algorithm to solve large-scale problems. In addition, we suggest a new genetic algorithm (GA2) with an adjusting algorithm to improve the performance of GA1. The basic mechanism of the GA2 is to provide an unidirectional partial move of products to available containers in the previous period. Finally, we analyze the results of GA1 and GA2 by evaluate the relative performance using the gap between the objective values of CPLEX and the each algorithm.

• The Korean Journal of Applied Statistics
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• v.28 no.6
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• pp.1075-1091
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• 2015

This paper reviews the developments of econometric analysis and seeks a statistical applicability to current economic phenomena. During the last half century, economic analysis has progressed continuously, analyzing and predicting a broad variety of economic phenomena. In the center of this progress lies the remarkable contribution of econometrics and mathematical statistics. New economic research environment has been recently created via developments of IT and the spread of internet and SNSs. Economic phenomena has become increasingly complicated along with more volatile and sophisticated economic analysis. In that context, it can be suggested that there is a need to move beyond current economic paradigms and adapt new approaches such as complex theory and econophysics, all of which posits as a challenge for econometrics and statistics.

• Korean Institute of Interior Design Journal
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• v.24 no.1
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• pp.34-42
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• 2015

This research is about shared living facilities for the solitary elderly in Gyeonggi province (so called "Carnation House"), which was opened after 2013. These facilities aim to help solving the social problems of the growing number of the solitary elderly. The research was conducted from April 2014 to October 2014 by using observation, measurement, photography, and interview methods. This research reviewed floor plan, area, accessibility, visual openness, and furniture and equipments. The results are as follows: First, considering the need for rest area and the protection of privacy, livingroom should at least be equipped with a variable wall or have a separate room. Secondly, for the kitchen plan, considering the fact that large number of people move simultaneously, kitchen entrance should be widened or LDK type is preferable. Thirdly, the bathroom entrance should be widened to at least 800mm and should have barrier free design. Fourthly, porch entrance should be planned to secure enough space and shoe cabinets for multiple users. Fifthly, to allow the users to enjoy outside view, the windows of living spaces should be placed no higher than 800mm from the floor level. Finally, for the location of the facility, people prefer the location be at the center of the village or near home. In addition, location with easy accessibility for the elderly is advisable. Therefore, establishing local guidelines for shared living facilities for the solitary elderly is advisable. When establishing local guidelines, local characters, culture and usage patterns should be considered.