• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.12-23
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• 2021

In the conventional experiment to assess the towing operations, the towing stability of the towed vessel has been evaluated under the condition without lateral motion of the tug-boat. However, the tug-boats may have a lateral force to change the direction of the towed vessel. In this study, experiments have been conducted considering unsteady conditions in the towing system. First, a towing test system in a Circular Water Channel (CWC) using the conventional experimental method is built. Second, the towing characteristics of the towed vessel are investigated using the conventional method, and they are compared with other research results and stability discriminant criteria. Third, the lateral motion of the tug-boat was modeled as a sinusoidal motion using a forced oscillation device changing frequency and amplitude. Finally, the discussion is given in terms of both towing- and course-stability of the towed vessel according to the lateral motion of the tug-boat.

• Structural Engineering and Mechanics
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• v.58 no.3
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• pp.533-553
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• 2016

In this paper, the recently developed meta-heuristic algorithm called tug of war optimization is applied to optimal design of castellated beams. Two common types of laterally supported castellated beams are considered as design problems: beams with hexagonal openings and beams with circular openings. Here, castellated beams have been studied for two cases: beams without filled holes and beams with end-filled holes. Also, tug of war optimization algorithm is utilized for obtaining the solution of these design problems. For this purpose, the minimum cost is taken as the objective function, and some benchmark problems are solved from literature.

• Journal of Navigation and Port Research
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• v.35 no.2
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• pp.113-119
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• 2011

This paper is a part of the development on the safe navigation model of tugs and barges in Korea waters. desk-top tug-barge simulator is to train the crew of tugs and barges, especially tugs' crew. It is connected with steering and engine telegraph console and winch control console, and can describe three types of operation mode for a tug-barge working unit, towing mode, side by side and push mode. It can also record and assess each simulation run. The evaluation module can confirm the result of a finished simulation run and help trainees to find and correct their faults, and it is composed of result evaluation and process evaluation.

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.262-270
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• 2011

This study examines the effects of spasticity, equilibrium and gait ability at lower extremity on lumbar stabilization exercise(LSE) with Swiss ball. This experiment was conducted to compare BBS, FRT, MAS and TUG by Swiss ball LSE with 34 stroke patients. equilibrium by BBS or FRT, spasticity by MAS and gait ability by TUG were measured after a 8-week traditional exercise physical therapy(17 subject of stroke patient) and a Swiss ball LSE(17 subject of stroke patient). These result lead us to the conclusion that BBS & FRT were statistically increased and MAS and TUG were decreased on Swiss ball LSE group. there were statistically differential effect between each group on FRT and MAS. These results suggest that Swiss ball LSE has the capability to improve spasticity, equilibrium and gait ability at lower extremity. Consequently, Swiss ball LSE would be lead to restoration of muscle spasticity, equilibrium and gait ability on stroke patients.

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.39-45
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• 2009

Purpose: The purpose of this study was to determine correlations between the Berg Balance Scale (BBS), Functional Reach Test (FRT), Timed Up & Go (TUG), Motor-Free Visual Perception Reach Test Vertical format (MVPT-V), Functional Independence Measure (FIM). Methods: The subjects used in this study were 35 stroke patients from Cheongju ST. Mary's hospital. Balance was measured by BBS, FRT. Functional mobility was measured by TUG. Visual perception was measured by MVPT-V. FIM was used to evaluate the activities of daily living. Data was analyzed using pearson product correlation. The TUG and MVPT-V index were analyzed by linear regression. Results: There was a statistically significant difference between FRT and BBS (r=0.89, p<0.01), FIM (r=0.74, p<0.05), MVPT-V (r=0.40, p<0.05), and TUG (r=-0.36, p<0.05). There was significant statistical differences between TUG and MVPT-V (r=-0.64, p<.01). However, statistically significant differences were observed between BBS and FIM (r=0.79, p<0.01). The visual close item of the MVPT-V showed the strongest variance in predicting TUG. Conclusion: The use of both quantitative and qualitive scales was shown to be a good measuring instrument for the classification of general clinical performances of stroke patients. In particular, the results suggest that the visual perception test may be able to predict functional locomotion in stroke patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5186-5194
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• 2014

Falls are one of the most serious problem that threatens the health of the elderly. This study was conducted twice a week for six weeks from May to June 2014 to evaluate the effectiveness of fall prevention exercises for rural seniors. This study analyzed the effects by comparing before and after exercise on the TUG, FRT, BBS, ADL, fear of falls, fall efficacy, and depression. The results of this study was as follows: Hypothesis1, "a TUG of post-test will improve more than the pre-test", was supported. Hypothesis3, "BBS of the post-test would improve more than the pre-test" was supported. In addition, the FRT, ADL, fear of fall, fall efficacy, and depression of post-test would improve more than the pre-test. Accordingly this study showed that fall prevention exercises are effective in improving the physical function (TUG, FRT, BBS, and ADL) and emotional function (fear of fall, fall efficacy, and depression) in rural seniors.

• Physical Therapy Korea
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• v.24 no.1
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• pp.97-104
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• 2017

Background: South Korea is one of fastest aging countries in the world. Poor balance and falls of the elderly are main health issues. Objects: The goal of this study was to understand the association between the socioeconomical factors and the standing balance of elderly living in the rural and urban area. Methods: One hundred sixty-six elderly participants who were older than 65 and were able to walk without an assistive device were recruited in the city of Gwangju and in the rural area of Jeonnam, South Korea. All participants performed the static and dynamic standing balance tests. Static standing balance was measured with chronometer in seconds while standing on one leg. Dynamic balance was tested with the timed up and go test (TUG), measured in seconds while getting up from a chair and walking 3 meters and back to sit. The static and dynamic standing balance was analyzed using analysis of variance and the Fisher's Least Significant Difference post hoc test. Results: Male participants from both areas had no difference in one leg standing and TUG. The female elderly living in rural area took shorter in TUG than females living in urban area. Age decreased the one leg standing time in both areas while did not affect the TUG significantly. As the monthly income increased, both of one leg standing and TUG increased in urban area, while the medium monthly income showed best performance (it was not statistically significant) in both of one leg standing and TUG in rural area. Conclusion: Socioeconomical factors affects differently the standing balance of the elderly living in rural and urban South Korea. Female living alone in urban area with low monthly income demonstrated worst standing balance in this study.

• Physical Therapy Korea
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• v.14 no.3
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• pp.64-71
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• 2007

The purposes of this study were to determine correlations between the Berg Balance Test (BBS), Timed -UP & Go Test, Fugl Meyer-L/E, Balance, Sensory (FM-L/E, B, S), Motor Assessment Scale-Gait (MAS-G), Comfortable maximal Gait Speed (C MGS), and the Modified Barthel Index (MBI). The subjects were 40 stroke patients of the Korea National Rehabilitation Center in Seoul. Main outcome measures were Balance control (BBS, FM-B), Gait (TUG, C MGS, MAS-G), ADL (MBI) and Motor Function of Lower Extremities (FM-L/E, S). The data were analyzed using Pearson product correlation. FM scales between other clinical and instrumental indexes and multiple stepwise regression analyses were performed to identify prognostic factors for Balance, Gait and ADL Motor Function of Lower Extremity inclinations. The results of this study were as follows: The BBS, FM-L/E, balance, sensory and MBI showed positive correlation relations, but TUG and C MGS showed negative correlations. The sensory factor of the FM-scale showed the strongest variance in predicting BBS. However the FM-balance showed the strongest variance in predicting TUG, MAS-G and C MGS. The use of both quantitative and qualitative scales was shown to be a good measuring instrument for the classification of the general clinical performance of the patients.

• Journal of the Korean Society of Marine Environment & Safety
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• v.28 no.6
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• pp.946-954
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• 2022

More than half of barges have been surveyed and designated as an "unmanned barge". The main advantage of the unmanned barge is that it can carry more cargo equivalent to 25 percent of freeboard compared to that of a manned barge. In contrast, it needs an onboard crew barge because the bargeman is in charge of several tasks during sailing such as mooring or unmooring barges to or from a wharf, dropping and heaving up an anchor and turning on and of navigational lights and shapes. The instant recognition is that a tug assume the responsibility of operating a barge; however, different situations exist in which the shipper, as the operator of the barge, hires a tug. Although a tug might be a carrier of a barge under a specific contract, the master of the tug should fulfill his duty to complete its voyage. Most masters are not provided with the particulars of a barge and the information regarding the bargemen onboard, which is believed not to respect the master's authority and lead to an unintended violation of relevant laws. This paper presents three recommendations for resolving these issues: the policy approach for changing unmanned barges to manned barges, issuing a minimum safe manning certificate, and providing the master of tug information on the barge and the crew onboard. Thus, the proposed approach can be expected to improve the crew's working conditions, diminish the violation of the maximum number of persons onboard the barge, and ensure the authority of the master of tug through such recommendations.

• Journal of Korean Physical Therapy Science
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• v.15 no.4
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• pp.1-9
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• 2008

Background: This study was to investigate effects of falls prevention exercise on functional fitness in elderly. Methods: A total of 45 healthy over 65years old adults (men=15, women=30) who were participated in this study. Exercise were involved in the period of 12 week complex physical training for around 50 minutes a day, three times per week. We measured subjects' physical activity levels by short physical performance battery(SPPB) test, timed up & go(TUG) test, one leg standing test(OLST) with closed eyes and maximal step length (MSL) test. Results: After falls prevention exercise, there were statically significant differences in SPPB, TUG, OLST and MSL test (P<.01) between pre and post test. There were statically significant differences in SPPB, TUG, OLST, MSL between pre and post test in men and women. There were statically significant differences between men and women in SPPB, TUG, OLST and MSL test. Conclusion: Falls prevention exercise had significant effects on physical fitness level in elderly, with a result increase muscle strength, balance ability and it might prevent falls.