• Journal of the Society of Naval Architects of Korea
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• v.58 no.5
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• pp.330-338
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• 2021

This paper focuses on the improvement of the influence coefficient matrix method for estimation of local ice load on the icebreaking research vessel ARAON. The influence coefficient matrix relates ice pressure on the hull plate to the measured/calculated hull strain/stress. Conventionally von Mises equivalent stresses representing hull stresses and ice pressure acting on the hull plate are utilized to assemble the influence coefficient matrix. Because of the three dimensional features of the ship-ice collision process, an enhanced method to assemble the influence coefficient matrix is derived considering ice loads in the X, Y, and Z direction simultaneously. Furthermore the location of ice loads acting on hull-plate may fall outside the measuring sensor area, and the enhanced influence coefficient matrix is modified to reduce the difference between the actual and the estimated ice loads by expanding the domain outward from the sensor area. The developed method for enhanced influence coefficient matrix is applied to IBRV ARAON during the 2019 Antarctic ice field test and the local ice loads in three directions are efficiently calculated compared to those by a conventional method.

• Journal of Distribution Science
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• v.12 no.7
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• pp.13-21
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• 2014

Purpose - This study reveals antecedent factors to help develop expressway rest areas in which employees were exposed to inferior environments, using Hackman and Oldham's Job Characteristics Theory. Research design, data, and methodology - The survey was conducted on 148 expressway rest area employees in Gyeonggi-do. After excluding questionnaires with invalid responses, 141 questionnaires were analyzed. Results - The sub-factors of job characteristics had a positive influence on the organizational commitment of employees, and organizational commitment had a positive influence on organizational citizenship behavior (OCB). Further, the results of mediation effects showed that organizational commitment and self-leadership were partially mediated. Finally, the results of the moderation effect of self-leadership showed that self-leadership was thought to be vital to let members endeavor to promote the competitiveness of expressway rest areas. Conclusions - The expressway rest area company needed to design jobs to let employees be self-motivated, productive, positive, responsible, and aspirational; job redesign, including job enrichment and job enlargement can be considerably helpful for affirmative influence.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.1083-1088
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• 2004

Several possibilities on the stability analysis of the railroad tunnels passing through the abandoned mining area are considered in this paper. Previous works on the influence zone due to cavities are investigated to study the effect of the safety deterioration near the cavities which are normally unknown to the engineers. Additional works on the numerical analysis of the influential zone are also performed in 3D space. The praximity of railroad tunnel and unexpected cavities is critical to influence the stability of railroad tunnel under construction. Futhermore, the study on the influence of underground condition like joint and faults should be significantly controlled under both design and construction stage.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1990.10a
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• pp.69-72
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• 1990

The live loads acting on structures are generally computed in terms of equivalent uniformly distributed loads for the simplicity in design process. The loads, therefore, tend to decrease with increasing influence area in both load intensity and variance. Since multi-story column loads result from accumulation of loadings acting on several different floors, its influence area becomes wider and lifetime maximum decreases. In the design codes proposing the design loads for types of structural members (i.e., slabs, beams, columns), not for tile change of influence area, some proper reduction factors are given for columns which support more than one floor. Using the live load models developed for colons supporting single floor, in this study, the probabilistic characteristics of multi-story column loads are analyzed. In addition reduction factors given for multi-story columns in current practice are calibrated.

• Computational Structural Engineering
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• v.5 no.3
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• pp.113-118
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• 1992

The live loads acting on structures are generally computed in terms of equivalent uniformly distributed loads for the simplicity in design process. The loads, therefore, tend to decrease with increasing influence area in both load intensity and variance. Since multi-story column loads result from accumulation of loadings action on several different floors, its influence area becomes wider and lifetime maximum decreases. In the design codes proposing the design loads according to types of structural members(i.e., slabs, beams, columns), rather than the change of influence area, some proper reduction factors are given for columns which support more than one floor. Using the live load models developed for columns supporting single floor, in this study, the probabilistic characteristics of multi-story column loads are analyzed. In addition reduction factors given for multistory columns in current practice are calibrated.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.3
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• pp.55-64
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• 2017

The problem of the population number of honeybees that is decreasing not only domestically but also globally, has a great influence on human beings and the entire ecosystem. The habitat of honeybees is recognized to be superior in urban environment rather than rural environment, and predicting for habitat assessment and conservation is necessary. Based on this, we targeted Cheonan City and neighboring administrative areas where the distribution of agricultural areas, urban areas, and forest areas is displayed equally. In order to predict the habitat preferred by honeybees, we apply the Maxent model what based on the presence information of the species. We also selected 10 environmental variables expected to influence honeybees habitat environment through literature survey. As a result of constructing the species distribution model using the Maxent model, 71.7% of the training data were shown on the AUC(Area Under Cover) basis, and it was be confirmed with an area of 20.73% in the whole target area, based on the 50% probability of presence of honeybees. It was confirmed that the contribution of the variable has influence on land covering, distance from the forest, altitude, aspect. Based on this, the possibility of honeybee's habitat characteristics were confirmed to be higher in wetland environment, in agricultural land, close to forest and lower elevation, southeast and west. The prediction of these habitat environments has significance as a lead research that presents the habitat of honeybees with high conservation value of ecosystems in terms of urban space, and it will be useful for future urban park planning and conservation area selection.

• Journal of Korean Physical Therapy Science
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• v.17 no.1_2
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• pp.67-76
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• 2010

Background: The purpose of this study was to evaluate the influence of ankle strategy exercise on balance ability in the women of octogenarians. Methods: Ankle strategy exercise group(n=14), leg strengthening exercise group(n=14) were measured an balance ability by Berg Balance Scale(BBS) scores and Balance Performance Monitor(BPM) at pre-intervention and post-intervention in 6weeks. Results: This study were summarized as follows : 1. The BBS scores, sway area, sway path length, sway maximum velocity of ankle strategy exercise group and leg strengthening exercise group were significantly different among the intervention period(p<.05). 2. The improvement of BBS scores, sway area, sway path length, sway maximum velocity were significantly different between ankle strategy exercise group and leg strengthening exercise group at in 6weeks(p<.05). Conclusion: Learned from the ankle strategy exercise could improve BBS scores, sway area, sway path length, sway maximum velocity and a balance for the women of octogenarians. Ankle strategy exercise need to be applied clinically for balance ability of the women of octogenarians.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.6
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• pp.143-152
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• 2000

The comer filling in shaped drawing process is an important characteristic, unlike the round drawing. It has also influence on the dimensional accuracy of the product. In this study, therefore, the shaped drawing process has been simulated by the three dimensional rigid-plastic finite element method in order to investigate the effect of process variables such as reduction in area and semi-die angle to the corner filling. The artificial neural network has also been introduced to reduce the number of simulations. To verify the results of simulations, experiments have been performed on the real industrial products. According to the results, the main process variable on the corner filling is the combination of semi-die angle in the irregular shaped drawing processes, but in the case of regular shaped drawing processes, reduction in area has great influence on the corner filling.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.3
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• pp.841-847
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• 2016

To study the influence of background color and substratum on hypermelanosis of starry flounder, we compared the daily food intake (DFI), the feed efficiency (FE), the survival, the growth, the ratio of pigmented area on the blind side and the ratio of hypermelanic fish duplicately reared for 180 days in dark-green FRP aquarium (control), white FRP aquarium together with dark-green substratum. The ratio of pigmented area on the blind side was significantly higher at the dark-green group than at the white group. DFI, FE and growth were higher in the dark-green substratum. Pigmented area rate and ratio of hypermelanic fish were significantly higher at the dark green group than at the high dark-green substratum. The results suggest that bright tank color and substratum bottom could inhibit the hypermelanosis.

• Journal of Korean Society for Atmospheric Environment
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• v.7 no.2
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• pp.105-113
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• 1991

An investigation is carried out for the role of topography in governign the mesoscale distribution of $SO_2$ concentration in Seoul. The three dimensional wind fields computed for a given synoptic meteorological condition by an atmospheric mesoscale model in the terrain following coordinate have been employed to compute the three dimensional mesoscale distributions of $SO_2$ concentration by the diffusion model in Seoul area. Terrain may affect the mesoscale distributions of $SO_2$ concentration through its influence on the mesoscale wind fields. This study discusses only the terrain effect on the concentration through its modification of the wind. This effect is to produce higher concentration in lower area according to the structure of divergence fields derived from and atmospheric mesoscale model.