• Journal of Institute of Control, Robotics and Systems
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• v.20 no.4
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• pp.402-407
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• 2014

In this paper, residual sway control of objects that are moved underwater is investigated. The fuel transfer system in a nuclear power plant transfers the nuclear fuel rods underwater. The research on the dynamics of the loads transferred in different mediums (water and air) and their control methods have not been fully developed yet. The attenuation characteristics of the fuel transfer system have been studied to minimize its residual vibration by considering the effects of hydrodynamic forces acting on the fuel rod. First, a mathematical model is derived for the underwater fuel transfer system, and then experiments have been conducted to study the dynamic behavior of the rod while it travels underwater. Lastly, the residual vibration at the end point is minimized using the input shaping technique.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1384-1385
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• 2006

Platinum is a candidate of top and bottom electrode in ferroelectric random access memory and dynamic random access memory. High dielectric materials and ferroelectric materials were generally patterned by plasma etching, however, the low etch rate and low etching profile were repoted. We proposed the damascene process of high dielectric materials and ferroelectric materials for patterning process through the chemical mechanical polishing process. At this time, platinum as a top electrode was used for the stopper for the end-point detection as Igarashi model. Therefore, the control of removal rate in platinum chemical mechanical polishing process was required. In this study, an addition of $H_{2}O_{2}$ oxidizer to alumina slurry could control the removal rate of platinum. The removal rate of platinum rapidly increased with an addition of 10wt% $H_{2}O_{2}$ oxidizer from 24.81nm/min to 113.59nm/min. Within-wafer non-uniformity of platinum after chemical mechanical polishing process was 9.93% with an addition of 5wt% $H_{2}O_{2}$ oxidizer.

• Journal of Power System Engineering
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• v.2 no.1
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• pp.67-72
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• 1998

In crane control system, it is required that the travelling time of crane must be reduced as much as possible and there is no the swing of load at the end and starting points. In this paper, we present a hybrid control method which includes two control methods of the optimal regulator and the velocity pattern control in order to realize high performance of the anti-sway. To implement the control algorithm, the dynamic equation is linearlized at an equilibrium point, so that the linear time invariant state equation can be obtained. A 1/10 sized model crane of the usual gantry cranes is made and used to show the applicability of the developed hybrid control method. The effectiveness of developed hybrid control method is proved by experimental results which show us good performance for anti-sway control comparing to conventional velocity pattern control. Practically, it is expected that the proposed control system will make an important contribution to the automatic crane control system of the industrial fields.

• International Journal of Contents
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• v.15 no.2
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• pp.53-58
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• 2019

The aim of this paper is to discuss how designers lead and direct 'technology-driven society' using their creative communication skill. To this end, it is required for communication designers to take conscious steps to recognize the future direction of their profession. Despite the advancement in technology, there is a human being at the center of all design activities. From a certain point of view, contemporary communication design takes an open-ended exploration of the subject matter, rather than a finished output. The notion of creative leadership may potentially expand more in terms of improving the methodology of today's visual culture. The paper will examine creative leadership that could be proposed by the challenge of discourse upon the upcoming industrial revolution. Today, communication designers are confronted by new leadership opportunities and challenges. Some leading designers seem to focus on brand new media technologies to prepare the 4th industrial revolutions. However, communication design cannot be discussed in the medium but can be understood as a process. Top-down and bottom-up process is always a concerned about the relationship since the focus of leadership has changed. In the top-down process, the leadership has existed between 'designer and client' because designers have played their role as a problem solver. On the other hand, there is a different model of leadership between 'design and technology' based on bottom-up process, which stem from the design authorship. In this regard, the new definition of creative leadership in the $4^{th}$ industrial revolution proposes a designer as a problem-finder based on the relationship between the 'designer and the public'.

• Journal of Korea Multimedia Society
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• v.24 no.5
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• pp.642-650
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• 2021

Strabismus is one of the most common disease that might be associated with vision impairment. Especially in infants and children, it is critical to detect strabismus at an early age because uncorrected strabismus may go on to develop amblyopia. To this end, ophthalmologists usually perform the Hirschberg test, which observes corneal light reflex (CLR) to determine the presence and type of strabismus. However, this test is usually done manually in a hospital, which might be difficult for patients who live in a remote area with poor medical access. To address this issue, we propose an automatic strabismus screening method that calculates the CLR ratio to determine the presence of strabismus based on image processing. In particular, the method first employs a pre-trained face detection model and a 68 facial landmarks detector to extract the eye region image. The data points located in the limbus are then collected, and the least square method is applied to obtain the center coordinates of the iris. Finally, the coordinate of the reflective light point center within the iris is extracted and used to calculate the CLR ratio with the coordinate of iris edges. Experimental results with several images demonstrate that the proposed method can be a promising solution to provide strabismus screening for patients who cannot visit hospitals.

• Korean Journal of Exercise Nutrition
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• v.25 no.2
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• pp.33-37
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• 2021

[Purpose] Sex hormones deficiency leads to dramatically bone loss in particular postmenopausal women. Royal jelly has anti-osteoporosis effect due to maintain bone volume in that condition. We hypothesized that royal jelly protein (RJP, a latent residue after extracting royal jelly) also prevents bone deficient in ovariectomized (OVX) female rats, the animal model of postmenopausal women. [Methods] Female Sprague-Dawley rats (n = 30, 6 weeks age old) were sham operated (Sham; sham operated group, n = 7), OVX control group (OC, n = 7), OVX with low RJP intake group (ORL, n = 8), and OVX with high RJP intake group (ORH, n = 8) during 8 weeks experimental periods. In the end point of this experiment, the bone samples (lumbar spine, tibia, and femur) were surgically removed under anesthesia. These bone samples were evaluated bone mineral density (BMD) and bone strength. [Results] BMD of lumbar spine in RJP intake groups (ORL, ORH) were higher than that in OC group (p < 0.05 and p < 0.01) in RJP intake volume dependent manner. BMD of tibial proximal metaphysis and diaphysis in RJP intake groups were also higher than these in OC group (p < 0.01 and p < 0.01 / p < 0.05 and p < 0.001). In addition, breaking force of femur in RJP intake groups were significantly increase compared with that in OC group (p < 0.001 respectively). [Conclusion] These findings indicate that RJP contribute to prevent sex hormone related bone abnormality.

• International Journal of Advanced Culture Technology
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• v.11 no.2
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• pp.267-275
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• 2023

The purpose of this study is to investigate the influence of sports center members' lifestyles on participation promotion and choice behavior. To this end, more specifically, we intend to establish and clarify a hypothetical model based on the preceding studies of facilitating factors and factors that continue to participate according to the lifestyle of sports center members. In order to achieve this research purpose, the study subjects were set as the population of male and female adults over 20 who are using sports centers in Gwangju Metropolitan City and Jeollanam-do in 2021. As for the sampling method, the sample was extracted using cluster random sampling, and 300 people were used for the actual analysis, excluding 60 copies of double-entry and insincere or unreliable questionnaires. The survey tool was modified and supplemented according to this study based on the questionnaire that had been verified for reliability and validity in previous studies, and all questionnaire items were composed of a 5-point scale. The statistical analysis used for data analysis was frequency analysis, exploratory factor analysis, reliability analysis, and multiple regression analysis using SPSS Windows 21.0 Version. The conclusions obtained in this study through data analysis by such methods and procedures are as follows. First, according to the lifestyle of sports center members, participation promotion factors were found to have a partial influence. Second, according to the lifestyle of sports center members, the selection behavior was found to have a partial influence. Third, it was found that the participation promotion factors of sports center members partially affected the choice behavior.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.3
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• pp.252-261
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• 2023

Analysis of dynamic characteristics and flight vibration test for unmanned aerial vehicles was studied by using dummy test body. The FEM model for dummy test body was supplemented by results of modal and random vibration test. The free end boundary condition to simulate flight environments was made by test setup using bungee cable. Prior to the flight vibration test using a dual electric vibration exciters, the test procedure to calculate quantitative vibration level was studied by using military specification. The actual test was successfully done by using the analysis and pretest results. From the analysis results, it was possible to determine the feasibility of the test by predicting the excitation force of the flight vibration test and to get the response of any point which could not be measured by the test. The results of this study will much contribute to the Test and Evaluation of unmanned aerial vehicles.

• Animal Bioscience
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• v.37 no.2_spc
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• pp.323-336
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• 2024

Molecular hydrogen (H₂) and formate (HCOO^-) are metabolic end products of many primary fermenters in the rumen ecosystem. Both play a vital role in fermentation where they are electron sinks for individual microbes in an anaerobic environment that lacks external electron acceptors. If H₂ and/or formate accumulate within the rumen, the ability of primary fermenters to regenerate electron carriers may be inhibited and microbial metabolism and growth disrupted. Consequently, H₂- and/or formate-consuming microbes such as methanogens and possibly homoacetogens play a key role in maintaining the metabolic efficiency of primary fermenters. There is increasing interest in identifying approaches to manipulate the rumen ecosystem for the benefit of the host and the environment. As H₂ and formate are important mediators of interspecies interactions, an understanding of their production and utilization could be a significant starting point for the development of successful interventions aimed at redirecting electron flow and reducing methane emissions. We conclude by discussing in brief ruminant methane mitigation approaches as a model to help understand the fate of H₂ and formate in the rumen ecosystem.

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1423-1436
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• 2010

The effects of meteorological and reclaiming conditions on the reduction of suspended particles are investigated using a computational fluid dynamics (CFD) model with the k-$\varepsilon$ turbulence closure scheme based on the renormalization group (RNG) theory. Twelve numerical experiments with different meteorological and reclaiming conditions are performed. For identifying the meteorological characteristics of the target area and providing the inflow conditions of the CFD model, the observed data from the automatic weather station (AWS) near the target area is analyzed. Complicated flow patterns such as flow distortion, horse-shoe vortex, recirculation zone, and channeling flow appeared due to the topography and buildings in the domain. Specially, the flow characteristics around the reclamation area are affected by the reclaiming height, reclaiming size and windbreak height. Reclaiming height affected the wind speed above the reclaiming area. Windbreak induces more complicated flow patterns around the reclaiming area as well as within the reclaiming area. In front of the windbreak, flow is distorted as it impinges on the windbreak. As a result, upward flow is generated there. Behind the windbreak, a secondary circulation, so called, a recirculation zone is generated and flow is reattached at the end of the recirculation zone (reattachment point). At the lower part of the recirculation zone, there is a reverse flow toward the windbreak. Flow passing to the reattachment point starts to be recovered. Total amounts of suspended particles are calculated using the frictional and threshold frictional velocities, erosion potential function, and the number of surface disturbance. In the case of a 10 m-reclaiming and northerly wind, the amount of suspended particles is largest. In the presence of 5 m windbreak, the friction velocity above the reclaiming area is largely reduced. As a result, the total amount of the suspended particles largely decreases, compared to the case with the same reclaiming and meteorological conditions except for the windbreak The calculated suspended particle amounts are used as the emission rate of the dispersion model simulations and the dispersion characteristics of the suspended particles are analyzed.