• Journal of the Korean Society of Safety
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• v.14 no.1
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• pp.33-40
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• 1999

In this paper, a damaged example of hanging guide frame used in the lifting of shore protection caisson was investigated. An examination of the stress and stability of members was carried out by structural analysis and the causes of damages was investigated. The stability analysis considering local and global stress buckling was performed. As a result of stability analysis. the first structure was unstable structure. Therefore improved structure was examined and the best effective methodology was the reassignment of wire.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.6
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• pp.849-859
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• 1998

The heat generated in an induction motor is mostly dissipated through the frame. The study on the heat transfer characteristics of a newly manufactured finless TEFC(Totally Enclosed Fan Cooled) induction motor showed/that it had an unsuitable structure in view of the heat transfer. The angle of the cooling air flow was very large and the ribs disturbed the air flow and partially generated the wake region on the frame. In the wake region the temperature was very high. Thus the heat transfer coefficients were lower than those of the frame with fins. Also was investigated the heat transfer characteristics of the motor frame by installing various guide vanes in the fan-side end cap. An optimum heat transfer case was found and the average heat transfer coefficient of the frame was 70% higher and the average coil temperature measured by the resistance method was 9 deg. C lower than that of the frame which had no guide vanes.

• East Asian mathematical journal
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• v.32 no.2
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• pp.153-174
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• 2016

The purpose of this study is to provide an opportunity for better understanding and application of 2009 revised elementary school mathematics textbooks through focus group's investigations on the elementary mathematics teacher's guide books. First, We survey previous studies on the teacher's guide books to make the frame of investigation. Next, We compose focus group(8 teachers) for 3~4th grades, and analyze the teacher's guide books according to ready-made frame: compliance of curriculum, accuracy and fairness of contents, selection and organization of contents. As results of investigation, system of organization of the teacher's guide books is needed. Goal, contents, teaching methods, and evaluations have to be consistent in describing mathematical terms. And errors in mathematics and mathematics education are examined more carefully. The teacher's guide books afford teachers many materials and informations to teach mathematics through classroom lessons. So more study on the teacher's guide books and developmental study for the model guidebooks is needed along with the revised curriculum and new textbooks.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.4
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• pp.226-231
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• 2003

There have been many attempts to make kart chassis domestically to lower the price of complete kart. However nobody made a successful chassis due to the lack of understanding the characteristics of kart chassis frame. In this work, a baseline chassis frame under the bending and torsional load is studied. Design target is that the baseline chassis frame is quite adequate not only for the beginners but also for the beginning racers. Results from the analysis are used as a guide to design or modify the baseline chassis with the goal of proper torsional stiffness. Minimum increase in weight is being forced. As a result, the baseline chassis frame was designed, made, and tested. Based on the design results, complete karts are being manufactured by the small 1 size domestic company and these karts are being sold and run in the market.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.42-48
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• 1994

This paper presents the navigation method for a mobile robot which uses a single camera and fluorescent lamp as a guide mark, projected on a convex mirror. The current position and heading direction of the mobile robot are obtained from the image of the guide mark. While the mobile robot travels to a goal position, the current position and heading direction of the mobile robot are updated continuously and the desired path and actual moving path are displayed on the monitor screen in real time. This proposed method eliminates the need to rotate the camera to track the guide mark, since a panoramic view of the surrounding area is available from the convex mirror, and natural guide marks such as usual florescent lamp on the ceiling or door frame can be used for navigation.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1051-1052
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• 2007

In this paper, as a clean lift, a maglev(magnetic levitation) clean lift is designed and described. The maglev clean lift, which is superior to conventional lifts in vibration, noise, clean class and speed characteristics, consists of magnets, guide rails, guide rollers, magnet module frame, cage, guidance controller, sensors, etc. As design specifications, the maximum value of vibration is 0.2G, the maximum value of noise is 60dB, and the clean class is #10. The design results for the maglev clean lift are shown and discussed.

• Journal of the Korean Society for Railway
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• v.2 no.2
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• pp.31-38
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• 1999

Two representative types of the AGT (Automated Guideway Transit) system, which are bogie and steering types, are available for the side-guided system. Each system primarily consists of the bogie frame, suspensions, wheelsets and axles, braking system and transmission system. Among these components, the bogie frame is one of the most significant components subjected to the whole vehicle and passenger loads. This paper describes structural analyses and associated fatigue analyses for each bogie frame depending on the various loading conditions on a basis of the railway vehicle code UIC 515-4. Subsequently, comparisons are made between those two types to estimate which type is more reliable in terms of strength and fatigue. It is observed that the bogie type is a little advantageous over the steering one from the strength analysis. However, the two types are found to be in a reliable range of fatigue even though a realistic fatigue load case is further carried out. In addition, an optimal size of thickness is suggested for designs of the bogie frame.

• Journal of the Ergonomics Society of Korea
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• v.30 no.4
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• pp.451-458
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• 2011

Objective: This study is to develop a design and evaluation guide to the ergonomic design of the farm working convenient equipments in order for the elderly to use them easily and safely. Background: The aging population has already increased in farm villages. But due to the usage of the farm working equipments that did not reflect the characteristics and functional changes of aging, accidents and patients with disease are increasing. Method: The study investigated the functional changes and physical, cognitive, and sensuous characteristics of the aged. By determining the criteria for classification of the convenient equipments by crop, and by finding out the items necessary for the ergonomic design, a guide to this study is proposed. Results: It is obvious that the physical, cognitive and sensuous functions change as the aging process continues. Therefore, for the design and evaluation of Control Panel, Control Lever, Frame Size, Shape, and Equipment Weight that are the necessary items for the ergonomic approach for the farm working equipments, such characteristics have to be reflected. Conclusion: Through this study, a guide to the design and evaluation of convenient equipments for the farm works that reflected the aging characteristics and functional changes has been proposed. Application: The result of this study is to expect not only designers but also related specialists to make the best use of it.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.2
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• pp.46-51
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• 2015

Since it is impossible to predict earthquakes, they involve more casualties and property damage compared to meteorological disasters such as heavy snow and heat waves, which can be predicted through weather forecasts. This has highlighted the need for seismic design and reinforcement. Recently, the use of composite materials as reinforcement has surged because steel plate reinforcement and section enlargement are likely to result in increased weight and physical damage to structures. This study evaluates the seismic performance of panels created from composite materials, and their guide systems. The specimens were miniature versions of actual steel structures, and displacement loads were applied in the transverse direction. Seismic performance was found to improve when structures were reinforced with seismic panels.

• Journal of the Korean Society for Railway
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• v.13 no.1
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• pp.1-8
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• 2010

In domestic developing magnetically levitated (Maglev) vehicle, bogie frames install electromagnets which provide the vehicles to run with levitation and guidance forces; moreover, the linear motors used for traction are integrated into the same mechanical structure. This paper presents the process which predicts the evaluation of life cycle for bogie frame on various running conditions. Durability analysis considering vibration effect is simulated by using random loads resulted from dynamic simulation which takes into account the irregularities of guide rail. And it supports additional weak points which were not examined in static analysis.