• Journal of the Korean Society for Heat Treatment
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• v.5 no.3
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• pp.165-170
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• 1992

The chip controls are investigated experimentally for the purpose of estimating cutting ability of hardened steel. In this experiment, hardened STD11 steel ($HR_c$ 60) is turned with carbide tool M20 under various cutting conditions and with several tool shapes. The main results obtained are as follows : 1) Cutting conditions of cutting speed 45m/min. feed 0.09-0.13 rev. depth of cut 0.4-0.6 are recommended for the chip excluding. 2) In case that the feed becomes larger and a lead angle of cutting tool becomes smaller, the chip excluding becomes easier. 3) It is confirmed that frank wear and crator wear on the cutting tool appear severely from about 10 min. after cutting start and chip excluding get worse.

• Journal of the Korean Institute of Navigation
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• v.16 no.3
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• pp.33-41
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• 1992

Handling performance of a vessel is greatly related with her steering characteristics which consist of two kinds of motion characteristics ; namely course stability and turning ability. The correct prediction of the qualities, especially the steering characteristics is as much important in ship handling as in ship design. It is the purpose of this paper to provide ships handlers better understanding of steering characteristics and then to help them in safe controlling and maneuvering of vessels presenting distinct inherent steering characteristic difference that lies between a fine-form vessel and full-form vessel. The authors calculated dynamic course stabilities of two kinds of ideal models, one of which represents a fine-form ship and the other a full-form ship, based on hydrodynamic data of forces and moments obtained by model tests in maneuvering tanks. The result of calculations indicated that a ship of full-form configuration has inhernet course instability. Though significant nonlinearties affect ship montions in maneuvers, application of linear theory is sufficient for prediction of the maneuvering characteristics of vessels on calm waters for handling reference.

• Korean Journal of Applied Biomechanics
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• v.20 no.2
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• pp.183-189
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• 2010

The balanced performance of dominant and non-dominant leg is very important to Taekwondo sparring. The purpose of this study was to investigate whether elite Taekwondo athletes would have balanced biomechanical performance and intra-limb coordination in executing different types of Taekwondo kicks. Twelve athletes(more than 10 year practice experience) participated in this study and performed six basic kicks(i.e., the front, roundhouse, side, back, thrashing, and turning-back kick). Results indicated no statistical difference on response time, peak kicking velocity, single limb vertical jump height, and angle-angle plot between dominant leg and non-dominant leg(p>.05). In conclusion, elite Taekwondo athletes had equivalent ability between dominant leg and non-dominant leg in performing Taekwondo kicks. This might be an advantage to elite athletes for Taekwondo sparring because they could use both leg without any restriction.

• Journal of the Korean Society for Marine Environment & Energy
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• v.4 no.1
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• pp.70-74
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• 2001

In this paper, we studied the maneuvering performances of a ship with flapped rudder. PMM tests were carried out for a ship model with horn type rudder or flapped rudder. The Abkowitz's model was used as a basic mathematical model to simulate the maneuvering motions. The maneuvering motions of a ship with flapped rudder were compared with those of a ship with horn-type rudder. As a result, it was found that the turning ability of a ship with flapped rudder was remarkably improved.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.6 no.9
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• pp.45-59
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• 1983

This study focuses on the growth and development of small and medium industries of Korea, orienting to the development of up-to-date technology from now on and bolstering their competitive ability in the rapidly changing international markets. For this purpose, the small and medium industries should 1) develop high-level manpower of up-to-date technology, 2) make constant efforts to categorize and divide the fields of technology with big business groups to boost their competitiveness, 3) raise automation rate by turning all facilities into mechatronics, 4) positively develop software know-how, 5) jointly conduct researches in cooperation with venture capital and Governmental research institute, 6) categorize an systematize the industries. On the Governmental level, there should be 1) wide-ranging support and assistance in technology, finance, and the facilities, 2) positive opening of consumer market, 3) assistance in technical cooperation with other nations, 4) and such indirect assistance as fostering the fields of related technology.

• Journal of the Korea Society for Simulation
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• v.6 no.1
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• pp.71-84
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• 1997

For many optimization problems where some of the system components are stochastic, the objective functions cannot be represented analytically. Therefore, modeling by computer simulation is one of the most effective means of studying such complex systems. Many, if not most, simulation optimization problems have multiple aspects. Historically, multiple aspects have been combined ad hoc to form a scalar objective function, usually through a linear combination (weighted sum) of the multiple attributes, or by turning objectives into constraints. The genetic algorithm (GA), however, is readily modified to deal with multiple aspects. In this paper we propose a MAGA (Multiple Aspects-based Genetic Algorithm) as an algorithm for finding the Pareto optimal set. We demonstrate its ability to find and maintain a diverse "Pareto optimal population" on two problems.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.9
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• pp.1667-1673
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• 2009

This paper presents a application of new algorithm for feeder reconfiguration problem in distribution systems. Harmony Search (HS) algorithm, which is motivated from the musical performance, is used to reconfigure distribution systems so that active power losses are globally minimized with turning on/off the sectionalizing and the tie-line switches. In optimization processing, the HS algorithm has searching ability for the global optimal solution, simple coding of the iteration procedure, and fast convergence to get the solution. The HS algorithm is tested on 15 buses and 69 buses distribution systems, and the results prove its effectiveness to determine appropriate switching options without the occurrence of any misdetermination in switching and get the minimum power loss.

• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.51-54
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• 2013

Not only Taenia solium and Taenia saginata, but also Taenia asiatica infects humans. The last species is not included in the evaluation of the specificity of the immunodiagnostic techniques for taeniasis/cysticercosis. There is currently no specific immunodiagnostic method for T. asiatica available. Therefore, due to the fact that molecular techniques (the only tool to distinguish the 3 Taenia species) are normally not employed in routine diagnostic methods, the 2 questions concerning T. asiatica (its definite geographic distribution and its ability to cause human cysticercosis), remain open, turning T. asiatica into the most neglected agent of human taeniasis-cysticercosis.

• Journal of Sensor Science and Technology
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• v.30 no.2
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• pp.67-70
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• 2021

A new button-shaped electrical device was developed for a smart fabric. This electric button can be sewn anywhere on the garment, similar to a traditional button fastener. t not only performs a decorative function but also makes the fabric suitable for use in Internet of Things (IoT) applications. It has metallic through-holes such that it can be fastened onto a fabric by conductive sewing threads. When threaded through metallic holes, the button can communicate with the external device by transmitting and receiving data. In addition, it adds specific functions by stacking a detachable application layer on the base layer. It is robust to frequent washing, and thus has excellent repeatability for use as an IoT device. The feasibility of the electric button was successfully demonstrated by its ability to identify the physical activities of walking and running, monitoring ambient temperature, and turning on LED lights.

• Physical Therapy Rehabilitation Science
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• v.6 no.3
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• pp.146-151
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• 2017

Objective: The purpose of this study was to investigate the effects rhythmic and non-rhythmic aerobic exercises on depression and balance of healthy elderly people. Design: Randomized controled trial. Methods: Nineteen older subjects were randomly divided into 2 groups for rhythmic and non-rhythmic aerobic exercises. Both aerobic exercises consisted of functional movements such as turning in opposite directions, and running in place, the exercise consisted of movements that could activate balance. The rhythmic training group initially used music with 8 beats, and then later progressed to 16 beats. Additionally, we adjusted the pace of the music using songs from 125 beats per minute (bpm) to 160 bpm. Both groups were exercised for 50 minutes a day, twice a week, for a total of 8 weeks. We measured the condition of the patients before the intervention, and after 8 weeks of intervention. The Beck depression inventory (BDI) was used to measure the degree of depression. The Berg balance scale (BBS) was used to measure static and dynamic balance ability. We measured the subject's subjective balance confidence using the fall efficacy scale (FES). Results: Both groups showed significant improvement in BDI, BBS, and FES (p<0.05). The rhythmic aerobic exercise group showed a significant improvement only in the BBS change values compared to the non-rhythmic group (p<0.05). Conclusions: According to this study, both rhythmic and non-rhythmic aerobic exercises resulted in significant improvement in the degree of depression and balance ability of the elderly. The rhythmic aerobic exercise was more effective for dynamic balance ability.