• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.32 no.1
• /
• pp.45-54
• /
• 2019

The damage detection method using the extended Kalman filter(EKF) technique has been continuously used since EKF can estimation the responses of the damaged building structure and the stiffness of the structure. However, in the use of EKF, the requirement of setting the initial paramters P, Q, and R has caused the divergence and instability of the state vector, and various researches have been conducted to determine theses parameters. In this paper, adaptive extended Kalman filter(AEKF) method is proposed to solve the problem of setting the values of P, Q, and R, which are important parameters determining the convergence performance of the EKF state vector. By using the AEKF method proposed in this study, the P, Q, and R parameters are updated every k steps. The proposed algorithm is applied for the estimation of stiffness and the damage detection of 3-DOF problem. Based of the verification, it can be found that the selection process for the values of P, Q, and R can improve the convergence performance of EKF.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.10a
• /
• pp.241-243
• /
• 2014

In this study, that by applying the algorithm of collective intelligence in helping to select the teaching methods and learning methods of learner and teacher, develop a content recommendation system, the teacher and the learner promote effective learning, I have intended to And for this reason can be applied to education recommended system to be applied to a movie or shopping mall recently, at the time of selection, it is appropriate in accordance with the state, such as the level of the learner, learning environment, learners the theme of teaching and learning, and to provide a teaching method and learning method, the learner can to find the learning method appropriate for the user, and a more efficient, Professor system that can save time to design the teaching learning process I developed, The utility and accuracy of the learning content recommendation system developed finally, after the data is accumulated in the use of a continuous schedule of the learner and a teacher, would need to be validated through the rating.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.42 no.3
• /
• pp.80-88
• /
• 2019

Recently, automobile manufacturing companies, which are major customers of them, are requiring IATF 16949 (ISO/TS 16949) certification as a mandatory requirement to secure product quality. In particular, IATF 16949 : 2016, revised in October 2016, was reinforced product traceability requirements for production information management by lot in the production process. Therefore, small and medium-sized precision parts processing companies in the automobile industry are very difficult to survive due to quality and price competition for customers satisfaction. MES (Manufacturing Execution System) is required to solve this problem. However, small and medium sized precision parts processing enterprises are reluctant to introduce the MES which is not suitable for the manufacturing environment of them such as high cost and low utilization. Even if the system is introduced, it is difficult to operate and maintain the system because the lack of computer manpower. In this paper, we propose a method for building a lot tracking system for small and medium precision parts processing companies by reviewing relevant literature and analyzing cases. In addition, by managing the production history for each lot of the final product in the system, we will grasp the effect of reducing the quality failure cost obtained by minimizing the range of defect selection.

• Journal of Science Education
• /
• v.43 no.2
• /
• pp.227-238
• /
• 2019

In this study, we investigated the perception of elementary school students on inquiry activities and collaborative problem-solving ability in data-based scientific inquiry. For this purpose, 20 data-based scientific inquiry classes were conducted in 26 elementary school students in Gyeongnam City. After selecting the inquiry problem, students conducted an inquiry process to collect data using digital inquiry instruments. The following results were obtained through questionnaires and interviews after the classes: First, students perceived the step on 'inquiry design and execution' as the most useful in the data-based scientific inquiry. Second, students perceived that their scientific ability and cooperation improved through data-based scientific inquiry, with the selection of inquiry problems being the most difficult. Third, students perceived positively the improvement of cooperative problem-solving ability. From the above results, it was found that data-based scientific inquiry is necessary to improve the elementary school students' scientific inquiry ability and cooperative problem-solving ability. Based on this research, we hope that the development and research of various inquiry activities will provide opportunities for inquiry that can cultivate various abilities needed for students living in the future.

• The Journal of Bigdata
• /
• v.3 no.2
• /
• pp.113-121
• /
• 2018

In this study, an augmented reality(AR)-based information management system for agricultural facility is proposed. Using a variety of sensed data transmitted by Lora-based wireless networks deployed at the agricultural facility, this system is capable of augmenting the sensed data and displaying them on the user's smartphone screen to provide visualized information to user. When users point their smartphone camera to the agricultural facility, the environment information collected from numerous sensors installed at the facility would be visualized and appear on the screen. Unlike traditional system which requires user to search a specific facility and then select sensor(s) to obtain the environment information, the proposed system shows the information on smartphone screen by augmenting it with real image captured by camera without doing a series of time-taking selection process. Since the way of acquiring information is through image or video, this system contributes to convenient monitoring and efficient management for agricultural facility.

• Journal of Embryo Transfer
• /
• v.33 no.4
• /
• pp.245-254
• /
• 2018

Pigs are considered as optimal donor animal for the successful xenotransplantation. To increase the possibility of clinical application, genetic modification to increase compatibility with human is an important and essential process. Genetic modification technique has been developed and improved to produce genetically modified pigs rapidly. CRISPR/Cas9 system is widely used in various fields including the production of transgenic animals and also can be enable multiple gene modifications. In this study, we developed new gene targeting vector and enrichment system for the rapid and efficient selection of genetically modified cells. We conducted co-transfection with two targeting vectors for simultaneous inactivation of two genes and enrichment of the genetically modified cells using MACS. After this efficient enrichment, genotypic analysis of each colony showed that colonies which have genetic modifications on both genes were confirmed with high efficiency. Somatic cell nuclear transfer was conducted with established donor cells and genetically modified pigs were successfully produced. Genotypic and phenotypic analysis of generated pigs showed identical genotypes with donor cells and no surface expression of ${\alpha}$-Gal and HD antigens. Furthermore, functional analysis using pooled human serum revealed dramatically reduction of human natural antibody (IgG and IgM) binding level and natural antibody-mediated cytotoxicity. In conclusion, the constructed vector and enrichment system using MACS used in this study is efficient and useful to generate genetically modified donor cells with multiple genetic alterations and lead to an efficient production of genetically modified pigs.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.30 no.6
• /
• pp.326-336
• /
• 2018

Continuous measurement of nearshore waves around Korea over long period is very demanding to setup plans for prevention of disasters of port and coastal structures. In this respect, a new web-based system, termed as WINK, was established, which collects nearshore wave data from Korea Meteorological Agency (KMA), Korea Hydrographic and Oceanographic Agency (KHOA), and Ministry of Oceans and Fisheries (MOF) and provide them after quality control of the data. This paper describes technical aspects regarding collection and selection of the wave observation data, construction of wave hindcasting data, the methodology of quality control for the selected wave data, and overall process of building the web-based data providing system.

• Journal of Digital Convergence
• /
• v.17 no.1
• /
• pp.357-364
• /
• 2019

This study comparatively analyzed hair damage by hair bleach particles and identified three different bleach particle sizes using a scanning electron microscope (SEM). The powdered bleaching agents made of ammonium persulfate (APS) and potassium persulfate had particle sizes of $131{\mu}m$, $72{\mu}m$ and $48.8{\mu}m$. According to a hair damage test, cuticle lift-up or peeling hardly occurred when small bleach particles were used. In terms of hair color, the hair bleached with larger bleach particles was the darkest, while the hair bleached with small bleach particles was the brightest. The results found that for bleaching agents that are more effective in easing hair damage, those with little particles should be used. In addition, it appears that the selection of particles depending on the degree of hair bleaching would enhance bleaching effects and reduce hair damage. The above process is a way to get great results in selecting a bleaching agent. It is anticipated that hair damage could be reduced during hair bleaching based on the above results.

• PNF and Movement
• /
• v.17 no.1
• /
• pp.157-166
• /
• 2019

Purpose: This study compares and examines the effects of proprioceptive neuromuscular facilitation (PNF) on patients with chronic low back pain through systematic literature review and meta-analysis. Methods: Domestic literature was searched with combinations of keywords including "proprioceptive neuromuscular facilitation," "PNF," "back pain," and "low back pain" using the Research Information Sharing Service (RISS), Korean Studies Information Service System (KISS), and Korean Medical Database (KMbase). Six studies (n=148) were finally included in the analysis through a selection and exclusion process. The quality of the studies was evaluated using the PEDro scale. Results: According to the meta-analysis results, the low back pains of the PNF group and the contrast group showed a standardized mean difference (SMD) of 2.21 (95% CI: -3.35, -1.07, p=0.01, $I^2=83%$) after intervention. Thus, the PNF group showed a statistically significant decrease in low back pain compared with the control group. In addition, the SMDs of the Oswestry Disability Index (ODI), lung function, and the Roland and Morris Disability Questionnaire (RMDQ) were -1.34 (95% CI: -1.88, -0.79, p<0.01, $I^2=35%$), 1.14 (95% CI: 0.49, 1.79, p=0.01, $I^2=0%$), and -1.59 (95% CI: -2.56, -0.62, p=0.01, $I^2=46%$), respectively. Thus, the PNF group showed statistically significant differences from the control group. Conclusion: At present, there is some limit to obtaining definite results about effect sizes because there are relatively few randomized controlled experiments that analyze the effects of PNF exercise in patients with chronic low back pain. Therefore, continuous efforts should be made to conduct randomized clinical trials and long-term efficacy studies in the future.

• Journal of the Korea Convergence Society
• /
• v.10 no.4
• /
• pp.7-16
• /
• 2019

As fierce competition is expected in the wearable devices marekt, it is needed to develop a technology planning that can increase consumer acceptance. This study aims to provide implications for technology planning of wearable devices by examining consumer preferences for the devices. For this purpose we employed a conjoint analysis. In the process of the analysis, we considered the trend of anticipatory standardization for wearable devices in an attempt to improve objectivity of analysis whilst many previous studies relied on focus group interview. For the anticipatory standardization information, we utilized liaisons and projects of wearable devices at International Electrotechnical Commission, and we designed a conjoint survey on the basis of the information. We conducted an online survey, and a total of 229 individuals responded to our survey. The result of conjoint analysis shows that main use and enhanced features were more important attributes than the others were. However, consumer preferences for detailed levels of each attribute were different by gender and age groups. This result implies that technology planning of wearable devices require distinct approaches by consumer segments.