• Journal of the Institute of Electronics Engineers of Korea SC
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• 제38권3호
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• pp.1-12
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• 2001

We consider the robust control problem for non-minimum phase(NMP) systems with parametric uncertainty. First, a new method that translates such an uncertain NMP system into a interval family of minimum phase(MP) transfer functions followed a time delay term in the form of Pade' approximation is presented. The controller to be proposed consists of a compensator with Smith predictor structure, so that it can compensate the time delay behaviour due to NMP plant. Therein, the main feedback controller for a family of MP plants has been designed by using quantitative feedback theory(QFT) such that satisfies the robust stability against the structured uncertainty. The stability and performance of overall system are examined through an illustrative example.

• Journal of Korean Elementary Science Education
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• 제29권2호
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• pp.207-218
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• 2010

The revised curriculum in 2007 adds an open inquiry approach to increase students' creativity and interest in science. Because it is the first time for elementary students to perform the open inquiry due to the national curriculum, it is essential that teachers give students' successful experiences in order to build a positive impression about inquiry activity. The purpose of this research is to develop and apply the open inquiry program. The research findings are as follows: First, we analyzed the students' traits of open inquiry ability during the program. The third and fourth grade students showed weakness in operating and inquiring abilities. They also feared failure and were unable to concentrate in classes which were based on explanation or discussion. When students had unexpected results, however, their inquiring abilities and creativeness increased considerably. Additionally there were some students who were stressed during the science-inquiry activity, due to no interest in science and an inability to think scientifically. Second, we developed an open inquiry program for elementary students. The program was modified, reflected upon the students' traits during open inquiry in class. Through repeated feedback like this, we completed the program. Third, for those who studied in the lessons there was a meaningful change in students' science inquiry abilities and abilities to perform 'formulating a hypothesis' and 'the control of variables'. These students' level of self-inquiry performance improved steadily. Moreover, they obtained a strong attachment to their inquiry and understood the method of quantitative experiments.

• Journal of Korean Academy of Nursing
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• 제49권4호
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• pp.398-410
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• 2019

Purpose: This study used a system dynamics methodology to identify correlation and nonlinear feedback structures among factors affecting adolescent cyberbullying victims (CV) in Korea and to construct and verify a simulation model. Methods: Factors affecting CV were identified by reviewing a theoretical background in existing literature and referencing various statistical data. Related variables were identified through content validity verification by an expert group, after which a causal loop diagram (CLD) was constructed based on the variables. A stock-flow diagram (SFD) using Vensim Professional 7.3 was used to establish a CV model. Results: Based on the literature review and expert verification, 22 variables associated with CV were identified and the CLD was prepared. Next, a model was developed by converting the CLD to an SFD. The simulation results showed that the variables such as negative emotions, stress levels, high levels of conflict in schools, parental monitoring, and time spent using new media had the strongest effects on CV. The model's validity was verified using equation check, sensitivity analysis for timestep and simulation with 4 CV adolescent. Conclusion: The system dynamics model constructed in this study can be used to develop intervention strategies in schools that are focused on counseling that can prevent cyberbullying and assist in the victims' recovery by formulating a feedback structure and capturing the dynamic changes observed in CV. To prevent cyberbullying, it is necessary to develop more effective strategies such as prevention education, counseling and treatment that considers factors pertaining to the individual, family, school, and media.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• 제19권1호
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• pp.279-287
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• 2019

In this paper, we attempted to analyze the balance ability of the body by measuring changes in body motion and plantar pressure distribution. So we developed a program that can measure and analyze range of motion and center of body pressure using inertial measurement unit(IMU) and FSR(Force Sensing Resistor) sensor, we also produced a contents that can help improve the balance ability. The quantitative values of range of motion and center of body pressure measured by this program are visualized in real time so that the user can easily recognize the results. In addition, the contents were designed to be adjusted according to the direction of improving the balance ability by adjusting the difficulty level based on the measured balance information. This can be achieved by increasing the concentration and participation will by using visual feedback method that proceeds while watching moving objects according to the user's motion.

• Journal of Broadcast Engineering
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• 제26권5호
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• pp.500-507
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• 2021

The virtual reality industry has an opportunity to take another leap forward with the surge in demand for non-face-to-face content and interest in the metaverse after Covid-19. Therefore, in order to popularize virtual reality content along with this trend, high-quality content production and storytelling research suitable for the characteristics of virtual reality should be continuously conducted. In order for content to which virtual reality characteristics are applied to be effectively produced through user feedback, a quantitative index that can evaluate the content is needed. In this study, the process of viewing virtual reality contents was analyzed and head movement was set as a quantitative indicator. Afterwards, the experimenter watched five animations and analyzed the correlation between recorded head movement information and immersion. As a result of the analysis, high immersion was shown when the head movement speed was relatively slow, and it was found that the head movement speed can be used significantly as an index indicating the degree of content immersion. The result derived in this way can be used as a quantitative indicator that can verify the validity of the storytelling method applied after the prototype is produced when the creator creates virtual reality content. This method can improve the quality of content by quickly identifying the problems of the proposed storytelling method and suggesting a better method. This study aims to contribute to the production of high-quality virtual reality content and the popularization of virtual reality content as a basic research to analyze immersion based on the quantitative indicator of head movement speed.

• Korean Journal of Construction Engineering and Management
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• 제10권4호
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• pp.3-13
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• 2009

When promoting BTL(Build Transfer Lease; below BTL) project, negotiation is a stage of examining observation and reflection of RFP(Request for Proposal below RFP) in terms with facilities, operating and financing. It keeps an important position in whole process. However, there is no consistent guideline or model which helps evaluating the result of negotiation. It is difficult to apprise the quantitative outcome after executing negotiation. Thus, this study presented the Value Engineering -based process and model of estimating the outcome of negotiation for the purpose of estimating and verifying the result of negotiation objectively, Evaluating factors of negotiation were classified into 6 fields, 38 divisions and 135 items, focused on cultural facilities on BTL project. Weight of every factor was estimated, and quantitative checklist was established. This study presented the model which could measure the outcome of negotiation. This result would be a critical checklist before negotiation on BTL project, an index of feedback during negotiation, and also a standard of estimating the outcome after negotiation.

• International Journal of Human Ecology
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• 제12권1호
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• pp.87-99
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• 2011

Purpose- The purpose of this study was to compare the fit of two prototype liquid cooled vests using a 3D body scanner and accompanying software. The objectives of this study were to obtain quantitative measurements of ease values, and to use these data to evaluate the fit of two cooling vests in active positions and to develop methodological protocol to resolve alignment issues between the scans using software designed for the alignment of 3D objects. Design/methodology/approach- Garment treatments and body positions were two independent variables with three levels each. Quantitative dataset were dependent variables, and were manipulated in 3x3 factorial designs with repeated measures. Scan images from eight subjects were used and ease values were obtained to compare the fit. Two different types of analyses were conducted in order to compare the fit using t-test; those were radial mean distance value analysis and radial distance distribution rate analysis. Findings- Overall prototype II achieved a closer fit than prototype I with both analyses. These were consistent results with findings from a previous study that used a different approach for evaluation. Research limitations/implications- The main findings can be used as practical feedback for prototype modification/selection in the design process, making use of 3D body scanner as an evaluation tool. Originality/value- Methodological protocols that were devised to eliminate potential sources of errors can contribute to application of data from 3D body scanners.

• Journal of Animal Reproduction and Biotechnology
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• 제37권2호
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• pp.96-105
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• 2022

The ovary undergoes substantial physiological changes along with estrus phase to mediate negative/positive feedback to the upstream reproductive tissues and to play a role in producing a fertilizable oocyte in the developing follicles. However, the disorder of estrus cycle in female can lead to diseases, such as cystic ovary which is directly associated with decline of overall reproductive performance. In gene expression studies of ovaries, quantitative reverse transcription polymerase chain reaction (qPCR) assay has been widely applied. During this assay, although normalization of target genes against reference genes (RGs) has been indispensably conducted, the expression of RGs is also variable in each experimental condition which can result in false conclusion. Because the understanding for stable RG in porcine ovaries was still limited, we attempted to assess the stability of RGs from the pool of ten commonly used RGs (18S, B2M, PPIA, RPL4, SDHA, ACTB, GAPDH, HPRT1, YWHAZ, and TBP) in the porcine ovaries under different estrus phase (follicular and luteal phase) and cystic condition, using stable RG-finding programs (geNorm, Normfinder, and BestKeeper). The significant (p < 0.01) differences in Ct values of RGs in the porcine ovaries under different conditions were identified. In assessing the stability of RGs, three programs comprehensively agreed that TBP and YWHAZ were suitable RGs to study porcine ovaries under different conditions but ACTB and GAPDH were inappropriate RGs in this experimental condition. We hope that these results contribute to plan the experiment design in the field of reproductive physiology in pigs as reference data.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제17권4호
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• pp.1216-1233
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• 2023

Conventional occupational therapy (OT) is conducted under the observation of an occupational therapist, and there are limitations in measuring and analyzing details such as degree of hand tremor and movement tendency, so this important information may be lost. It is therefore difficult to identify quantitative performance indicators, and the presence of observers during performance sometimes makes the subjects feel that they have to achieve good results. In this study, by using the Unity3D and artificial intelligence (AI) speaker, we propose a system that allows the subjects to steadily use it by themselves and helps the occupational therapist objectively evaluate through quantitative data. This system is based on the OT of the sensory integration approach. And the purpose of this system is to improve children's activities of daily living by providing various feedback to induce sensory integration, which allows them to develop the ability to effectively use their bodies. A dynamic OT cognitive assessment tool for children used in clinical practice was implemented in Unity3D to create an OT environment of virtual space. The Leap Motion Controller allows users to track and record hand motion data in real time. Occupational therapists can control the user's performance environment remotely by connecting Unity3D and AI speaker. The experiment with the conventional OT tool and the system we proposed was conducted. As a result, it was found that when the system was performed without an observer, users can perform spontaneously and several times feeling ease and active mind.

• The Journal of Information Systems
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• 제33권1호
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• pp.45-68
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• 2024

Purpose This paper examines the role of local market-based communities in driving regional revitalization, using detailed analysis of online networks. We aim to dissect a local community's communication network, highlighting members with high engagement levels and exploring their characteristics. Our goal is to identify the conditions that allow local community networks to grow independently and to demonstrate how the activation of these networks contributes to regional revitalization. Design/methodology/approach We employ a mixed-methods approach, combining social network analysis with statistical techniques to investigate the structure of online communication networks. Specifically, we use ANOVA to determine the statistical significance of our findings, ensuring their reliability. To complement our quantitative data, we include qualitative insights from interviews, adding depth and context to our analysis. Findings Our results show that individuals with high centrality in the online network are crucial for maintaining active local communities. We find that leveraging local resources to create a supportive and adaptable environment is essential for the communities' sustainability and expansion. Importantly, our research draws a direct connection between the vitality of local community networks and the broader process of regional revitalization. We argue that energizing local communities is an effective way to address the risk of regional decline. By integrating quantitative analysis with qualitative feedback, this study contributes to the understanding of local market-based communities as key drivers of regional development. It emphasizes the importance of building vibrant, resourceful community networks to revitalize areas experiencing socio-economic challenges.