• Journal of Intelligence and Information Systems
• /
• v.29 no.3
• /
• pp.211-227
• /
• 2023

Personal service robots, a type of social robot that has emerged with the aging population and technological advancements, are undergoing a transformation centered around technologies that can extend independent living for older adults in their homes. For older adults to accept and use social robot innovations in their daily lives on a long-term basis, it is crucial to have a deeper understanding of user perspectives, contexts, and emotions. This research aims to comprehensively understand older adults by utilizing a mixed-method approach that integrates quantitative and qualitative data. Specifically, we employ the Van Kaam phenomenological methodology to group conversations into nine categories based on emotional cues and conversation participants as key variables, using voice conversation records between older adults and social robots. We then personalize the conversations based on frequency and weight, allowing for user segmentation. Additionally, we conduct profiling analysis using demographic data and health indicators obtained from pre-survey questionnaires. Furthermore, based on the analysis of conversations, we perform K-means cluster analysis to classify older adults into three groups and examine their respective characteristics. The proposed model in this study is expected to contribute to the growth of businesses related to understanding users and deriving insights by providing a methodology for segmenting older adult s, which is essential for the future provision of social robots with caregiving functions in everyday life.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.7
• /
• pp.205-218
• /
• 2019

Music sampling, which has been popular since hip-hop DJs used it in the 1970s, is now one of methods of producing music that is used regardless of genre or country. In this study, an overall production methodology for music sampling was presented through in terms of content and techniques. First of all, in terms of the contents, we classified them into the reuse and length of materials, and the function of samples in the mixed songs. In terms of the techniques, editing and effecting techniques were classified. By combining these elements, the methodology of music sampling applicable to the productions as well as the analysis was presented. Based on this methodology, the sampled songs of Korean Popular musicians - Jang Ki-ha and Faces, Epik High, The Quiet, and DJ DOC - were successfully analysed. Through the analysis process, the organic relationship of elements within the methodology was investigated, and the results of the analysis showed the effectiveness of the proposed methodology. This study can be meaningful in laying the groundwork for applying music sampling directly when actually producing songs or analyzing sampled songs.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.44 no.1
• /
• pp.84-95
• /
• 2020

Wearing ease is a critical factor when designing special uniforms such as flight pilot's garment and should reflect occupational properties for better performance. This study measured skin surface on 31 areas in seven postures that refer to the pilot's occupational postures as well as made six prediction models including linear mixed model (LMM) for each body part to find the best fit model. Skin surface measured from 3D body scanned images of 11 male pilot participants. There were significantly positive and negative changes in various areas from standing posture (P1) to dynamic postures (P2-P7). Six models were designed in various compositions using stature and chest circumference as fixed effects and subject and posture as random effects. The best models were linear mixed models with one fixed effect (chest circumference or stature, varies with body parts) and two random effects (subject and posture). The results of this study provide reference data to set wearing ease for pilot's garment and suggests a new methodology in this research area, but verifying the effect of diverse independent variables is left for future studies.

• Membrane and Water Treatment
• /
• v.10 no.2
• /
• pp.165-178
• /
• 2019

Mixed matrix membranes (MMMs) of poly (vinyl alcohol) (PVA) containing certain amounts of H-${\beta}$ zeolite for pervaporation were manufactured by using a solution casting protocol. These zeolite-embedded membranes were then characterized with scanning electron microscope (SEM), X-ray diffraction (XRD) and swelling tests. The membrane separation performance has been examined by means of isopropanol (IPA) dewatering from its highly concentrated aqueous solutions via response surface methodology (RSM). The results have demonstrated that the influences of feed IPA composition (85-95 wt.%), feed temperature ($50-70^{\circ}C$), zeolite loading (15-25 wt.%) and their interactive influences are all statistically significant on both pervaporation flux ($398-1228g/m^2{\cdot}h$) and water/isopropanol separation factor (617-2001). The quadratic models based on the RSM analysis have performed excellently to correlate experimental data with very high determination coefficients and very low relative standard deviations. The optimal pervaporation predictions given by using the RSM models demonstrate a total flux of $953g/m^2{\cdot}h$ and separation factor of 1458, and are excellently verified by experimental results. As reflected by these results, PVA MMMs embedded with hydrophilic $H-{\beta}$ zeolite entities have performed considerably better than its pure counterpart and indicated great potential for isopropanol dehydration applications.

• Journal of the Korea Convergence Society
• /
• v.13 no.3
• /
• pp.163-172
• /
• 2022

The purpose of this study is to present implications in the planning and design methodology for revitalization of public spaces for mixed-use residential building. For the purpose, I have taken a literature research and a site analysis with cases of 'Kyungsung Univ.·Bukyung Nat'l Univ. Station'-area in Busan City. The analysis framework was consist of spatial composition, street facilities, use behavior, and connection with the street. The result of this study is as follows; 1) It is needed to consist of an empty space practically usable in an open location that is easy to access by the general public. 2) Considering the use of people, it is needed to install street furniture that can actually be used for rest. 3) It is needed to make a plan and design that considers the access and use of the general public and the space through it. 4) It is needed to create a synergistic effect in the integration of the street and the public space and the linkage with the street through this.

• Journal of the Korean School Mathematics Society
• /
• v.16 no.1
• /
• pp.265-287
• /
• 2013

The purpose of this study was to analyze the trends of domestic research on teacher knowledge in mathematics in terms of its conceptualizations of teacher knowledge, topics, methods, subjects, and content domains. For this purpose, the papers published in 9 professional journals during the recent 14 years (1999-2012) were analyzed by 5 criteria. The results of this study showed that the concept of PCK was the most frequent, whereas its subcategories appeared in different forms. The most frequent research topic was survey of teacher knowledge. The qualitative research methodology was more frequently used than the quantitative methodology, whereas mixed one was hardly used. The subjects for research included a little more elementary school teachers than secondary counterparts, but did similarly both pre-service and in-service teachers. Whereas both the research on number and operations in elementary mathematics education and the research on function in secondary were active, the rest of content domains were not. On the basis of these results, this paper provides several implications for future research direction in teacher knowledge in mathematics.

• KSBB Journal
• /
• v.22 no.4
• /
• pp.222-227
• /
• 2007

Biodiesel (fatty acid methyl esters) have used to as substitutes for petro-diesel by mixed-form with petro-diesel. In several processes of biodiesel production, alkali-catalyst transesterification produced to biodiesel of high contents with short reaction time. In this study, we investigate the optimal condition of alkali-catalyst transesterification of rapeseed oil produced at Jeju island in Korea using response surface methodology. The optimal condition of biodiesel production is reaction temperature 59.7$^{\circ}C$, catalyst amount 1.18%, oil to methanol molar ratio 1:8.75, and reaction time 5.18 min. At that reaction condition, the fatty acid methyl ester contents of product are above 97%. Our results may provide useful information with regard to the development of more economic and efficient biodiesel production system.

• The Journal of the Korea Contents Association
• /
• v.18 no.11
• /
• pp.430-446
• /
• 2018

In this paper, we conducted a comparative study on the methodology for impact analysis as the economic grounds for formulating policy and investment plan concerned with utilizing spectrum resource. In order to provide numerical results for objective comparison and selection among policy and investment planning, methods to be analyzed are focused on quantitative methodology based on mathematical models, consequently the utility and limits of econometric model, input-output analysis, computable general equilibrium and system dynamics are compared from various viewpoints including analysis cost. Besides, we compared the methodologies in the standpoint of utilizing spectrum and discussed the recent findings of mixed models combining multiple methodologies to exploit the advantages of each methodology and to offset the limit. Results of the research can be used as reference indicators to select the method that conforms to the purpose and priority of analysis verifying the efficiency of execution of policies and investment plans.

• The Korean Journal of Applied Statistics
• /
• v.31 no.1
• /
• pp.123-137
• /
• 2018

A nonlinear mixed effects model is mainly used to analyze repeated measurement data in various fields. A nonlinear mixed effects model consists of two stages: the first-stage individual-level model considers intra-individual variation and the second-stage population model considers inter-individual variation. The individual-level model, which is the first stage of the nonlinear mixed effects model, estimates the parameters of the nonlinear regression model. It is the same as the general nonlinear regression model, and usually estimates parameters using the least squares estimation method. However, the least squares estimation method may have a problem that the estimated value of the parameters and standard errors become extremely large if the assumed nonlinear function is not explicitly revealed by the data. In this paper, a new estimation method is proposed to solve this problem by introducing the ridge regression method recently proposed in the nonlinear regression model into the first-stage individual-level model of the nonlinear mixed effects model. The performance of the proposed estimator is compared with the performance with the standard estimator through a simulation study. The proposed methodology is also illustrated using quantitative high throughput screening data obtained from the US National Toxicology Program.

• Journal of the Korean Geographical Society
• /
• v.49 no.3
• /
• pp.405-422
• /
• 2014

Two important issues in hedonic model are to specify accurate model and delineate submarkets. While the former has experienced much improvement over recent decades, the latter has received relatively little attention. However, the accuracy of estimates from hedonic model will be necessarily reduced when the analysis does not adequately address market segmentation which can capture the spatial scale of price formation process in real estate. Placing emphasis on improvement of performance in hedonic model, this paper tried to segment real estate markets in Gangnam-gu and Jungrang-gu, which correspond to most heterogeneous and homogeneous ones respectively in 25 autonomous districts of Seoul. First, we calculated variable coefficients from mixed geographically weighted regression model (mixed GWR model) as input for clustering, since the coefficient from hedonic model can be interpreted as shadow price of attributes constituting real estate. After that, we developed a spatially constrained data-driven methodology to preserve spatial contiguity by utilizing the SKATER algorithm based on a minimum spanning tree. Finally, the performance of this method was verified by applying a multi-level model. We concluded that submarket does not exist in Jungrang-gu and five submarkets centered on arterial roads would be reasonable in Gangnam-gu. Urban infrastructure such as arterial roads has not been considered an important factor for delineating submarkets until now, but it was found empirically that they play a key role in market segmentation.