• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.47 no.4
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• pp.435-442
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• 2011

In an attempt to respond to the increase in international oil prices and reduce operating expenses, ship remodeling was carried out on a 740ton class tuna purse seiner. To strengthen the competitiveness of the fisheries industry by improving vessel performance, a bulbous bow was newly equipped. The slipway and rudder area were also lengthened and enlarged with the propeller and main engine remained unchanged. To reduce the hull resistance, a circle type bulbous bow was attached on the hull behind bow thruster and thus the cost for exchanging electrical equipment for bow thruster was reduced. The new rudder area was expanded 15% more than the old one within the extent that the existing mechanical control part and rudder stock were not changed. To prevent fishing net damage and stabilize wake field, slipway was lengthened to the optimal position. All of the new design of remodeling parts went through the model tests in towing tank and CWC. Besides resistance test, all of necessary model test results were delivered for hydrodynamic character for the modified ship. The maneuvering simulation to verify that the remodeled ship satisfies the IMO rules was performed in both zigzag and turning tests. The estimated resistance with new bulbous bow and lengthened stern was reduced by 4.8% in the 2-dimensional analysis and 17.4% in the 3-dimensional analysis in comparison of conventional ship. The average reduction of resistance was estimated about 10%. Maneuvering character of modified hull form was found to satisfy all regulations under IMO. The remodeling of tuna purse seiner can not only improve fishing performance but also contribute to reduction of operating cost by saving energy for the fisheries industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5487-5494
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• 2014

This study examined the relationship between income and the value of leisure to develop a more accurate model of the labor market without necessarily losing the primary merit of the received model. Moreover, with an improved understanding of the labor market dynamics, it can be seen that progressive era labor market legislation, which was designed to mitigate the effects of the bargaining power inequality in low wage labor markets, was in fact based on sensible economic foundations. These low-wage dynamics present an example of a positive feedback system or "vicious circle" at work in the economy. The market dynamics of the low wage sector push the wage away from the range that is consistent with a self-regulating market.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6114-6118
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• 2013

This study examined the ultrasonic pulse reflection method(UPRM) for testing each ultrasonic pulse waveform model(UPWM) based on weld defects. The sharp crack of a clear signal was generated. The echo height of the defective probes changed according to the location. In a long crack in a circle around the defective probes, the Swivel scanning echo height when using the particle was reduced drastically. The peaks in the echo were thin because the needle was pointed. The porosity defects arising from a single echo was sharp and crisp, but a number of pores of the collective reflection overlapped and ajagged echo was observed. Slag, slag inclusions, cracks, and defects at the Swivel scan of each particle using the echo shape showed difference in the degree. Cracks were revealed as sudden changes in the echo height of the slag inclusions: increase ${\rightarrow}$ decrease ${\rightarrow}$ increase ${\rightarrow}$ decrease. In addition, the location of a number of defects in the dense pore geometry, such as a typical echo sundry, revealed the shape in the slag. Poor penetration of the defect echo, revealed the cracks to have a sharp-edged, crack-like shape with an echo.

• Journal of Navigation and Port Research
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• v.28 no.10 s.96
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• pp.827-832
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• 2004

Up to now a lot of the study on ship collision avoidance systems have proceeded actively. However the rate of ship collision accidents hasn't decreased yet. If there is collision risk in close quarters situation in spite of maneuvering ship for collision avoidance according to the system, only use of TCP A and DCP A as input factor for collision risk decision is not useful to avoiding collision action. For the recent 5 years by the analysis of first observation distance about approaching ship in domestic collision accidents, nearly $45\%$ of accidents is close first observation less than 2 miles. Therefore it is essential part for safety navigations to study for collision avoidance action in close encounter. In this paper, as a fundamental study of supporting collision avoidance maneuvering for navigators, we proposed ship collision avoidance support model in close quarters situation through analysis qf collision accidents to effectively get rid of the causes.

• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.3
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• pp.118-125
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• 2004

The purpose of this study is to decide an appropriate neighborhood and a transition rule of cellular automata by analyzing the past growth process of urban areas in Gimhae. With cellular automata which can manage the change based on the dynamic model and time, this study analyzes the urban growth of Gimhae from 1987 to 2001. Also, through the simulation of different types for neighborhood and transition rules, we can find the appropriate neighborhood and the transition rule for Gimhae. In conclusion, the forecast of physical urban growth pattern is more accurate under conditions when the number of matrixes for the neighborhood is small, the shape of the neighborhood is rectangular, "${\alpha}$" value, which control the pace of urban growth, is low and the transition possibility ($P_{ij}$) is high.

• Journal of Korean Association for Spatial Structures
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• v.6 no.1 s.19
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• pp.111-115
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• 2006

The effects of porous wind fence on the pressure characteristics around low-rise building model were investigated experimentally. Flow characteristics of velocities and turbulences behind wind fence were measured using hot-wire anemometer The wind fence characterize by varying the porosity of 0%, 20% and the distances from the wind fence from 1H to 9H with maintaining the uniform flow velocity of 6 m/s. we investigated the overall characterization of the low-rise building by measuring pressure seventy four on model. The effects of porosity fences varied with the porosity of the fence and measurement locations(1H-9H). The 20% porosity proved to be effective for the protection area of 1H to 3H, but the 40% porosity proved to be effective for the protection area of 4H to 6H.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.12
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• pp.158-164
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• 2015

Lane detection is one of the key parts among autonomous vehicle technologies because lane keeping and path planning are based on lane detection. Camera is used for lane detection but there are severe limitations such as narrow field of view and effect of illumination. On the other hands, Lidar sensor has the merits of having large field of view and being little influenced by illumination because it uses intensity information. Existing researches that use methods such as Hough transform, histogram hardly handle multiple lanes in the co-occuring situation of lanes and road marking. In this paper, we propose a method based on RANSAC and regularization which provides a stable and precise detection result in the co-occuring situation of lanes and road marking in highway scenarios. This is performed by precise lane point extraction using circular model RANSAC and regularization aided least square fitting. Through quantitative evaluation, we verify that the proposed algorithm is capable of multi lane detection with high accuracy in real-time on our own acquired road data.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.165-174
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• 2010

Ganggangsulae, a traditional Korean circle-dance play, is valuable as the material for learning the traditional culture. Most people realize the importance of the Ganggangsulae as the traditional play. However, schools have experienced difficulties in teaching the Ganggangsulae to students since students are not interested in it due to the lack of systematic and proper instruction methods. In order to develop these methods, it is required to enforce researches in reinventing traditional Ganggangsulae into modern and popular life sports based on various scientific analyses. In this paper, we analyze the current instruction methods and the corresponding effects in teaching Ganggangsulae in the elementary schools. Also the effect of exercise is also analyzed for each play of Ganggangsulae. Based on these analyses, we present a model of player-centric Ganggangsulae system which can be reorganized its plays for a specific purpose. The proposed model characterizes Ganggangsulae in terms of the evolutionary variety and modular structure.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2757-2763
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• 2015

p-Snake is an energy minimizing algorithm that applies an additional prototype energy to the existing Active Contour Model and is used to extract the contour line in the area where the edge information is unclear. In this paper suggested the creation of a prototype energy field that applies a variable prototype expressed as a combination of circle and straight line primitives, and a fudge function, to improve p-Snake's contour extraction performance. The prototype was defined based on the parts codes entered and the appropriate initial contour was extracted in each primitive zones acquired from the pre-processing process. Then, the primitives variably adjusted to create the prototype and the contour probability based on the distance to the prototype was calculated through the fuzzy function to create the prototype energy field. This was applied to p-Snake to extract the contour from 100 images acquired from various small parts and compared its similarity with the prototype to find that p-Snake made with the adaptive prototype was about 4.6% more precise than the existing Snake method.

• Hwankyungkyoyuk
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• v.22 no.3
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• pp.49-62
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• 2009

This study started from the need to change the technocentric view of environment into the ecocentric one to overcome ecological crisis today. Thus, the purposes of this study are to reorganize characteristics of ecocentrism, to analyze ecocentrism of Native North Americans as a realistic model, and to finally find suggestions to environmental education. The results of this study can be summarized as follows; Frist, the ecocentric perception on relationship between human beings and nature pursues co-existence through harmony and balance based on holistic understandings. And the ecocentric perception on relationship among human beings attempts to preserve environment by overcoming rule structure among them. The ecocentric perception on relationship between human beings and spirituality is to set life goals to achieve spirituality rather than to pursue material life. Second, Native North Americans have a holistic world view that human beings and nature are an inseparable one through the symbol of 'the Sacred Circle'. They also lived simple lives which satisfies vital needs instead of pursuing material lives in terms of the perception on relationship among human beings. When it comes to the perception on relationship between human beings and spirituality, they feel sacredness from all things in daily life and want to have peaceful relationships with their own inside through spirituality toward 'Mother Earth'. Third, the ecocentrism of Native North Americans make suggestions that environmental education confirm again what roles of human beings are in ecosystem, and that it helps students develop ecological sensitivity by giving them many opportunities to go to field trips. Furthermore, environmental education helps them positively think about and actively choose simple life. In addition, it has to be designed to help students seek sacredness in daily life through ecological imagination. This study has values of newly organizing characteristics of each ecocentric idea by integrating it from complementary aspects, and pursuing direction of ecocentrism and its realistic possibility by analyzing the ecocentrism of Native North Americans as a model of ecological life.