• Animal cells and systems
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• v.13 no.1
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• pp.83-89
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• 2009

Investigations were made on population biology of Pampus echinogaster (Basilewsky, 1855) in the coastal areas of Korea, Yellow Sea, between August 2005 and July 2006. Population structure was not significantly different between male and females. Monthly variation of gonadosomatic index (GSI) of both sexes defined spawning period extending from March through July. A similar pattern was also observed in change at maturity stages. For males and females GSI was positively correlated with hepatosomatic index (HSI). Fecundity, ranging from 41,250 to 103,610 eggs, was related to body size, indicating that body size is the useful determinant of fecundity. The sexual maturity ($L_{50}$) was estimated as 14.98 cm TL for males and 19.32 cm TL for females. Parameters of growth estimated by the modified von Bertalanffy growth function model showed that the values of $L_{\infty}$ and K for combined data were 39.12 cm TL and 0.65 $yr^{-1}$. The growth performance index of this study (2.75) was higher than that of the previous study (2.45). This difference could be attributed to sampling method. The recruitment patterns indicated one normally distributed group. Percentage of the recruitment was 51.04% in the spawning season and the highest in August (19.78%).

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.36-48
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• 1999

Fatigue life and crack retardation behavior after penetration were experimentally examined using surface pre-cracked specimens of aluminium alloy 5083. The Wheeler model retardation parameter was used successfully to predict crack growth behavior after penetration. By using a crack propagation rule, the change in crack shape after penetration can be evaluated quantitatively. Advanced, waveform-based acoustic emission (AE) techniques have been successfully used to evaluate signal characteristics obtained form fatigue crack propagation and penetratin behavior in 6061 aluminum plate with surface crack under fatigue stress. Surface defects in the structural members are apt to be origins of fatigue crack growth, which may cause serious failure of the whole structure. The nondestructive analysis on the crack growth and penetration from these defects may, therefore, be one of the most important subjects on the reliability of the leak before break (LBB) design. The goal of the present study is to determine if different sources of the AE could be identified by characteristics of the waveforms produced from the crack growth and penetration. AE signals detected in four stages were found to have different signal per stage. With analysis of waveform and power spectrum in 6061 aluminum alloys with a surface crack, it is found to be capabilities on real-time monitoring for the crack propagation and penetration behavior of various damages and defects in structural members.

• Journal of the Korean Society of Systems Engineering
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• v.17 no.1
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• pp.107-113
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• 2021

Plant Configuration Management(CM) is an activity to maintain consistency of design requirements, physical configuration, facility configuration information throughout the life cycle of the plant by systematically managing changes that occur during the plant design and operation process. Conformity between information must be ensured not only in the design stage, but also in the case of design changes in the operation and maintenance stages, and thus a computer system capable of efficiently managing them is required. In particular, in consideration of an application to small and medium-sized domestic plants, a computer system that can support configuration management at a low cost is needed. Accordingly, in this study, a configuration management system has been developed to support the management of plant design information and change procedures in the operation stage of small and medium-sized plants. Here, a case for quantitatively evaluating the effectiveness of the developed system is described.

• Asia-Pacific Journal of Business
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• v.9 no.1
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• pp.77-89
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• 2018

Today, the sports teams are in a highly competitive environment where they don't know what may happen in the near future. While the front-runner teams suffer a serious slump, the teams in lower ladder stacks victories. This recent phenomenon proves that no team can secure the sustainable competitive edge over others. This is the time when a complete change of the mindset about the short-term competitive edge is needed. Therefore, we conducted the case study to the short-term competitive edges by selecting OK Savings Bank Rush & Cash volleyball team(hereafter referred to as OK Savings Bank). Thus, we presented the Transient Advantage Wave which describes the five stages of Initiating-Promotion-Utilization-Reconstruction-Withdrawal as a framework for the case study. Finally, we organized the results of the analysis and based on this result, we discussed the significance and the limitation of the short-term competitive edge that the sports team should pursue. This study contributed to the changes in strategies & tactics of various sports teams by suggesting the new strategy called short-term competitive edges that teams should utilize in order to get the best results in the sports league that has the strong quality of Time-based system.

• Journal of Information Technology Applications and Management
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• v.31 no.3
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• pp.39-52
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• 2024

The development of autonomous driving technology is expected to bring about a major change in the mobility rights of the transportation vulnerable. It is very important to identify user requirements in developing autonomous vehicles and service technologies for the transportation vulnerable. User requirements were derived for the wheelchair disabled and the walking disabled. Through focus interviews, a total of 58 requirements were derived for wheelchair-using disabled people and 53 requirements for walking disabled people. A Kano survey was conducted on 33 wheelchair disabled and 34 walking disabled. After that, the quality types of functional requirements in terms of autonomous vehicles and service environment development were analyzed using the Kano model. Priority analysis was conducted on the functions required by the wheelchair disabled and the walking disabled. The results of this study can be used as basic data to determine the priorities of user function requirements in the early stages of autonomous vehicle and service technology development.

• Journal of Korea Game Society
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• v.21 no.2
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• pp.17-32
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• 2021

This study focused on the games that were in the spotlight during the One Source Multi-use era, analyzing game based movies and the games. Through this, we wanted to examine the phenomena, changes, and in-depth meanings of the genre and grammar. Using Vogler's "12 Stages of the Hero Journey" and Greimas's "Model actantie" the three works of Need for Speed, Assassin Creed and Warcraft were cross-analyzed. Through this analysis, we looked at the structure of the discourse and identified the significant messages brought by the change in text.

• Journal of Power Electronics
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• v.13 no.1
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• pp.59-69
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• 2013

An alternative technique to control multilevel inverters with vector approximations has been presented. The innovative control method utilizes specially designed two-dimensional hysteresis comparators to simplify the implementation and improve the resultant waveform. The multistage inverter designed with maximum number of levels is operated in such a way to approximate the reference voltage vector by exploiting the large number of multilevel inverter vectors. A three-stage inverter with the main high voltage stage made of three phase, six-switch and singly-fed inverter is considered for application to the proposed design. The proposed control concept is to maintain a higher voltage stage state as long as it can lead to a target vector. High and medium voltage stages controllers are based on surface hysteresis comparators to hold the switching state or to perform the necessary change to achieve its reference voltage with minimal switching losses. The low voltage stage controller is designed to approximate the target reference voltage to the nearest inverter vector using the nearest integer rounding and adjustment comparators. Model simulation and prototype test results show that the proposed control technique clearly outperforms the previous control methods.

• Structural Engineering and Mechanics
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• v.25 no.1
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• pp.39-52
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• 2007

This paper describes an experimental study on structural health monitoring of a 1:3-scaled one-story concrete frame subjected to seismic damage and retrofit. The structure is tested on a shaking table by exerting successively enhanced earthquake excitations until severe damage, and then retrofitted using fiber-reinforced polymers (FRP). The modal properties of the tested structure at trifling, moderate, severe damage and strengthening stages are measured by subjecting it to a small-amplitude white-noise excitation after each earthquake attack. Making use of the measured global modal frequencies and a validated finite element model of the tested structure, a neural network method is developed to quantitatively identify the stiffness reduction due to damage and the stiffness enhancement due to strengthening. The identification results are compared with 'true' damage severities that are defined and determined based on visual inspection and local impact testing. It is shown that by the use of FRP retrofit, the stiffness of the severely damaged structure can be recovered to the level as in the trifling damage stage.

• Journal of Preventive Medicine and Public Health
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• v.38 no.1
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• pp.82-92
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• 2005

Objective : To evaluate the relationships among sociodemographic characteristics, health behaviors, levels of pros and cons and stages of change in Pap testing for uterine cervical cancer. Methods : A questionnaire survey was performed on 560 randomly sampled people who were assigned to participate in a Pap testing program by the National Cancer Screening Project in 2003' between 25 September and 10 October in Gyeonggi, Korea. Data about the behaviors and intentions of Pap testing, sociodemographic characteristics, health behaviors, and levels of acknowledged benefit (pros) and barrier (cons) for Pap testing was collected. The stages of change were grouped according to behaviors and intentions of Pap testing as passive, active, and relapse. Results : Logistic analysis between the passive and active groups showed that city dwellers, 'high' and 'middle' groups in terms of the individual s health belief, those who had undergone a health examination within the past 2 years, and those who had undergone hormone replacement therapy had a higher odds ratios to be in the active group. As the 'benefit' scores increased and the 'Unnecessity' scores decreased, the probabilities to be in the active group increased. According to the logistic analysis results between the active and relapse groups, those who were 60 years or older, members of the National Heath Insurance, and those who had not undergone a health examination within the past 2 years had a higher odds ratio to be in the relapse group. The 'Benefit' scores were not significant in this relationship. The probabilities of being in the relapse group increased as the Unnecessity and 'Shamefulness' scores increased. Conclusions : In conclusion, health planners should inform women in the passive group of the benefits and necessity of Pap testing. It would be better to reduce the barriers to the active group of undergoing Pap smear. This study might be a useful guide for future planning of Pap testing program.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.1
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• pp.10-20
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• 2019

Individual dental age is used as an index of chronological age estimation and is an important indicator of the child's growth stage. Dental age does change greatly over time, but it changes constantly. And updating information about this change is important. The purpose of this study was to provide information about tooth eruption stage using diagnostic model analysis and to investigate tooth eruption sequence and estimate chronological age based on this information. Tooth eruption stages were measured on a diagnostic model from 488 patients in 5 - 13 year old children. Based on the information on eruption stage, eruption sequence in maxilla was first permanent molar, central incisor, lateral incisor, first premolar, canine, second premolar and second permanent molar. Eruption sequence in mandible was first permanent molar, central incisor, lateral incisor, canine, first premolar, second premolar and second permanent molar. There were significant differences between males and females in the eruption stage of canine, first and second premolar, and second molar at several ages. The chronological age of male and female was estimated by the coefficient of determination of 0.816, 0.826 respectively.