• Korean Journal of Occupational Health Nursing
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• v.9 no.1
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• pp.49-55
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• 2000

When standing, walking, or running for extended periods of time, fatigue occurs in the legs. Although there are many ways, to release tense or fatigued leg muscles, in the case that there is insufficient time to relax, an easy way to release leg fatigue is using an inclined step (about 3 minutes). This method was more effective than performing stretching exercises as studied. An experiment was conducted on a golf course in the Kangwon province in Korea. Subjects were chosen randomly and consisted of 5 females and 4 males golf caddies. Their main tasks consisted of pulling golf carts to the bottom of a hill for 8 to 10 hours and sometimes lifting and lowering golf clubs during the duration of one day. EMG was measured after work and after using the previously mentioned inclined Steps for the lower legs using ME3000P. This study investigated the types of inclined Steps which would be most effective and appropriate for golf caddies, whether sex difference had any influence existed between male and female workers. The results showed that a step with a $20^{\circ}$ angle was most effective for males and a step with a $25^{\circ}$ angle was most effective for females. Females showed faster recovery from fatigue than males. However, there were no statistical significance between males and females.

• Journal of the Semiconductor & Display Technology
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• v.5 no.2 s.15
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• pp.19-25
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• 2006

This paper focuses on lossy medical image compression methods for medical images that operate on three-dimensional(3-D) irreversible integer wavelet transform. We offer an application of unbalanced tree structure algorithm to medical images, using a 3-D unbalanced wavelet decomposition and a 3-D unbalanced spatial dependence tree. The wavelet decomposition is accomplished with integer wavelet filters implemented with the lifting method. We have tested our encoder on volumetric medical images using different integer filters and coding unit sizes. The coding unit sizes of 16 slices save considerable dynamic memory(RAM) and coding delay from full sequence coding units used in previous works. If we allow the formation of trees of different lengths, then we can accomodate more transaxial scales than three. The encoder and decoder can then keep track of the length of the tree in which each pixel resides through the sequence of decompositions. Results show that, even with these small coding units, our algorithm with certain filters performs as well and better in lossy coding than previous coding systems using 3-D integer unbalanced wavelet transforms on volumetric medical images.

• Korean Journal of Occupational Health Nursing
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• v.8 no.2
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• pp.156-161
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• 1999

The EMG(Electromyography) analysis was used to identify the fact the degree of inclined step was selected as dependent variable and feet muscle fatigue was selected as a independent variable. In a final result from EMG test. the shift in median frequency (MF) with 20, 25, 30, 35 degree of inclined steps indicated that 30 degree step was identified as most effective for a decrease in feet muscle fatigue. In a department store, 80% of the workers are female standing sales workers. They work at standing on average 10 hours per day. They performed heavy duty jobs such as lifting, lowering. packing and carrying heavy materials. Furthermore, even though they have work shoes, they usually use various kind of high heels. Eventually, this situation develops low-back-pain (LBP) problems for female workers. In conclusion, it is recommended that a particular branch in a department store claimed this step can effectively to circulate blood and significantly decrease feet muscle fatigue in lower extremity.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.617-635
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• 2020

The purpose of this study is to discuss how to improve the maneuverability of lifting and diving for underwater vehicle's vertical motion. Therefore, to solve these problems, applied the 3-D numerical simulation, Taguchi's Design of Experiment (DOE), and intelligent parameter design methods, etc. We planned four steps as follows: firstly, we applied the 2-D flow simulation with NACA series, and then through the Taguchi's dynamic method to analyze the sensitivity (β). Secondly, take the data of pitching torque and total resistance from the Taguchi orthogonal array (L9), the ignal-to-noise ratio (SNR), and analysis each factorial contribution by ANOVA. Thirdly, used Radial Basis Function Network (RBFN) method to train the non-linear meta-modeling and found out the best factorial combination by Particle Swarm Optimization (PSO) and Weighted Percentage Reduction of Quality Loss (WPRQL). Finally, the application of the above methods gives the global optimum for multi-quality characteristics and the robust design configuration, including L/D is 9.4:1, the foreplane on the hull (Bow-2), and position of the sail is 0.25 Ls from the bow. The result shows that the total quality is improved by 86.03% in comparison with the original design.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.6_2
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• pp.937-946
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• 2021

The floating crane is used to lift the heavyweight on the ocean. The floating crane has a winch system for lifting the heavyweight and the system is controlled by the winch control system. The heavyweight is lifted safely by control of the winch control system. Before the make the control system and controller, there are many restricted conditions to test and validate at design and development steps. In order to solve the problems, commonly use the HILS (Hardware-In-the-Loop-Simulation). HILS is the method of test and validation for the hardware control system. It can be composed of the control system in hardware with surrounding environments which is a virtual model. In this study, we developed the winch system model for HILS of the 150t winch control system in a floating crane. Through this simulation and winch model, it can be applied to HILS for the winch control system.

• Korean Journal of Construction Engineering and Management
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• v.17 no.6
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• pp.3-12
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• 2016

The purpose of this study is to provide a domestic applicable modular building construction process by benchmarking international best practices. In this study, we derive the risk factors that may occur in performing a modular construction projects and the modular construction management factors through case analysis. In order to effectively respond to risks in performing a modular building projects, we propose the modular building construction process which is separated by a transportation, lifting, assembly steps based on the unit module construction sequence. It is the key to providing management information and guidelines for the design, production, construction participants by reflecting the information for each step in the process. This study would prevent a potential hazard which may occur in the construction process. Consequently, It could result in saving the entire cost of modular construction project as shortening the project schedule and could improve workability of modular construction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.4
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• pp.567-574
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• 2006

This paper focuses on lossy medical image compression methods for medical images that operate on three-dimensional(3-D) irreversible integer wavelet transform. We offer an application of unbalanced tree structure algorithm to medical images, using a 3-D unbalanced wavelet decomposition and a 3-D unbalanced spatial dependence tree. The wavelet decomposition is accomplished with integer wavelet filters implemented with the lifting method. We have tested our encoder on volumetric medical images using different integer filters and 16 coding unit size. The coding unit sizes of 16 slices save considerable dynamic memory(RAM) and coding delay from full sequence coding units used in previous works. If we allow the formation of trees of different lengths, then we can accomodate more transaxial scales than three. Then the encoder and decoder can then keep track of the length of the tree in which each pixel resides through the sequence of decompositions. Results show that, even with these small coding units, our algorithm with I(5,3)filter performs as well and better in lossy coding than previous coding systems using 3-D integer unbalanced wavelet transforms on volumetric medical images.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.389-398
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• 2012

In this study, structural strain responses of the jacket-type Uldolmok tidal current power plant structure under severe tidal environments were measured and analyzed using long-term measurement system during construction and also operation. It was observed that there were significant changes in strain responses at the steps of jacket lifting, block loading, pile ejection and insertion. Strains due to dead loads and tidal loads were analyzed before and after removal of a jacket leg, and it was also found that the strains due to dead load were much significantly changed after jacket leg removal. From the measurement data during operation, it was found that strain responses were fluctuated with M2 and M4 tidal periods and also relatively short period of about 10 min due to the peculiar tidal characteristics in the Uldolmok strait. Finally, the neural network-based non-parametric estimation models were investigated to build up the signal-based structural damage monitoring system.

• Journal of Drive and Control
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• v.18 no.4
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• pp.19-27
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• 2021

A bunker bed is a type of furniture that efficiently utilizes a narrow indoor space by having a high bed and using the empty space below as a living and storage space. The demand for multi-purpose furniture is increasing due to the recent increase in single-person households and wide-spread shared accommodation. According to the consumer research, one of the major drawbacks of a bunker bed was to get on and off the bed through a ladder or stairs. In order to overcome these problems, it was confirmed that the height adjustment function that can easily adjust the minimum and maximum heights of the bed was necessary. In this study, a height adjustable bunker bed was designed by using a gas spring that generates a repulsive force by the compressed gas inside. The design process consisted of the following three steps: Firstly, the hysteresis characteristics due to a friction and spring constant of a commercial gas spring were confirmed by measuring the repulsive force vs. compressed displacement. Secondly, requirements of the vertical lifting force exerted on the bed against gravity force were derived. Finally, the height-adjustable bed using the four-bar link mechanism was designed with 4 parameters so that the bed weight of 60-70 kgf could be adjusted to 800 mm in height by an affordable initial operation force. The performance was verified through prototype production and the results of vertical displacement and force to move were nearly the same as designed. In addition, an electrically operated height-adjustable bed was also designed with linear actuators and the performance was proved with the prototype.