• The Journal of the Acoustical Society of Korea
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• v.27 no.2E
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• pp.57-63
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• 2008

Stethoscopic auscultation is still one of the primary tools for the diagnosis of heart diseases due to its easy accessibility and relatively low cost. It is, however, a difficult skill to acquire. Many research efforts have been done on the automatic classification of heart sound signals to support clinicians in heart sound diagnosis. Recently, hidden Markov models (HMMs) have been used quite successfully in the automatic classification of the heart sound signal. However, in the classification using HMMs, there are so many heart sound signal types that it is not reasonable to assign a new class to each of them. In this paper, rather than constructing an HMM for each signal type, we propose to build an HMM for a set of acoustically-similar signal types. To define the classes, we use the KL (Kullback-Leibler) distance between different signal types to determine if they should belong to the same class. From the classification experiments on the heart sound data consisting of 25 different types of signals, the proposed method proved to be quite efficient in determining the optimal set of classes. Also we found that the class determination approach produced better results than the heuristic class assignment method.

• The Journal of the Korea Contents Association
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• v.21 no.2
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• pp.395-405
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• 2021

This study explored the structural relationship between achievement goal orientation, learning motivation, and level of interest on the level of flow in distance PBL classes. A structural model was constructed through analysis of previous studies. Data for the verification of the structural model were collected from 59 students in the teaching courses. The study took PBL lessons remotely. After the PBL class was ended, flow, achievement goal orientation, learning motivation, and level of interest were measured. The collected data were analyzed using the structural equation model analysis method. As a result, the structural model proposed in this study was verified to be valid. It was verified that the level of interest mediated the influence of achievement goal orientation and learning motivation to influence commitment. Next, it was verified that the path through which the level of interest mediates the effect of achievement goal orientation has the greatest influence. Therefore, it is possible to suggest that the level of flow can be adjusted if the level of interest is adjusted in consideration of the achievement goal orientation of learners when operating distance PBL classes.

• Journal of architectural history
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• v.14 no.4 s.44
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• pp.73-86
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• 2005

The purpose of this study is to prove the correlations among various factors what determined to formation of front elevation proportion system through making an actual survey and investigating. According to the analysis of them, we make conclusions as follows; 1, On the assumption that average distance of 1Kan(間) is 1, the height of foundation is 0.21, the height of floor from foundation is 0.24, the height of normal column from floor is 0.85, the height of eaves from foundation is 1.10. 2. Southeast faced buildings are wider than southwest faced buildings in the distance of 1Kan (間) in the range of $110{sim}220mm$. The height of foundation and floor in the southeast faced buildings are higher than those in southwest faced buildings beside the height of normal column, eaves, high column in the southwest faced buildings are higher than those in southeast faced buildings. 3. As number of front Kan(間) increases, the distance of 1Kan(間) decrease and the height of eaves and high column(高柱) increases. This is cause of making a maximum needed inner space by increasing the distance of 1Kan(間). This is an wisdom for living from ancestors. 4. As number of Dori(道里) increases, the distances of 1Kan are nearly same but the height of eaves and high column(高柱) increases about 300mm, This is a natural result from an increasing of building scale. 5. The distance of 1Kan(間) in later 19C building is most wide but, the unit heights are minimal average values at year 1900 as a reference mark. After this, the height of normal column, eaves, high column are higher about $170{sim}330mm$. 6. The number of Kan in front elevation, Dori(道里), and direction of building have correlations each other in proportion system of traditional housing An-Chae with significant level, p<0.05.

• International Journal of Contents
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• v.6 no.1
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• pp.12-19
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• 2010

In this paper, attendance in distance learning courses of a cyber university has been surveyed in an effort to verify the effectiveness of distance learning. Based on survey data from 4,749 distance learning participants, major attending place, major reasons for attending online class, fidelity to online classes, attending time per week, perceived educational effectiveness, perceived and relative seriousness of problems, and other variables have been evaluated. The results indicate that perceptional seriousness of the investigated problems is not statistically important. The findings indicate that, among operational problems, self willingness and cheating are the most remarkable. In contrast, the relative seriousness of traditionally recognized problems such as H/W availability and network speed among environmental problems is least remarkable. An analysis of demographic differences such as sex, employment, and school year in terms of seriousness of problems is also performed. The results reveal the existence of statistically significant differences according to sex, employment, and school year with regard to almost all elements of environment, actual current conditions, and seriousness of problems, with the exception of some elements such as attending place and perceived fidelity.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.1
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• pp.51-63
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• 1997

Total suspended particulate matters in the ambient air were analyzed for eight chemical elements (Ca, Co, Cu, Fe, Mn, Pb, Si, and Zn) using an x-ray fluorescence spectrometry (XRF) at the Kyung Hee University - Suwon Campus during 1989 to 1994. To use these data as basis for source identification study, membership of each sample was selected to represent one of the well defined sample groups. The data sets consisting of 83 objects and 8 variables were initially separated into two groups, fine (d$_{p}$<3.3 ${\mu}{\textrm}{m}$) and coarse particle groups (d$_{p}$>3.3 ${\mu}{\textrm}{m}$). A hierarchical clustering method was examined to obtain possible member of homogeneous sample classes for each of the two groups by transforming raw data and by applying various distances. A disjoint principal component analysis was then used to define homogeneous sample classes after deleting outliers. Each of five homogeneous sample classes was determined for the fine and the coarse particle group, respectively. The data were properly classified via an application of logarithmic transformation and Euclidean distance concept. After determining homogeneous classes, correlation coefficients among eight chemical variables within all the homogeneous classes for calculated and meteorological variables (temperature. relative humidity, wind speed, wind direction, and precipitation) were examined as well to intensively interpret environmental factors influencing the characteristics of each class for each group. According to our analysis, we found that each class had its own distinct seasonal pattern that was affected most sensitively by wind direction.ion.

• The KIPS Transactions:PartD
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• v.11D no.7 s.96
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• pp.1443-1450
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• 2004

The clustering characteristics for a number of classes, and defining the inheritance relations between the classes is a difficult and complex problem in an early stage of object oriented software development. We discuss a traditional iterative approach for the reuse of the existing classes in a library and an integrated approach to creating a number of new classes presented in this study. This paper formulates a character-istic clustering problem for zero-one integer programming and presents a network solution method with illustrative examples and the basic rules to define the inheritance relations between the classes. The network solution method for a characteristic clustering problem is based on a distance parameter between every pair of objects with characteristics. We apply the approach to a real problem taken from industry.

• Journal of Technologic Dentistry
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• v.42 no.4
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• pp.402-408
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• 2020

Purpose: To understand the students' level of recognition of online classes in the Department of Dental Technology and to provide the basic data for designing online classes based on the dental technology course. Methods: A survey was conducted among the students of the dental technology department. The collected data was analyzed with the SPSS ver. 25.0 program. To ensure a reliable verification, the α=0.05 significance level was used. The t-test and analysis of variance were also performed. Results: The students' level of recognition of online classes in the Department of Dental Technology is shown in the rate of recognition for video-based classes for both the theory and experiments. Students displayed high positivity with the video-based learning as it is repeated learning that is not affected by the limitations of time. In addition, video-based learning is highly beneficial in terms of convenience, satisfaction, and achievement for learning. Conclusion: Based on the results, video-based learning is a highly positive learning type for students. It was also recommended that the Department of Dental Technology should offer a post-COVID-19 online class to include the blended methods of a face-to-face class and video-based learning.

• Journal of applied mathematics & informatics
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• v.29 no.1_2
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• pp.327-335
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• 2011

Explicit formulas are given for the first and second Zagreb index, degree-distance and Wiener-type invariants of splice and link of graphs. As a consequence, the first and second Zagreb coindex of these classes of composite graphs are also computed.

• Journal of Engineering Education Research
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• v.23 no.6
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• pp.60-67
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• 2020

This study was conducted to understand the experiences of engineering college professors teaching classes online due to COVID-19. Instructional strategies were proposed based on these results. This study qualitatively analyzed interviews of four engineering college professors who switched from teaching classes offline to teaching them online in the first semester of 2020. The results showed that the professors had difficulties in creating video content, interacting with students, and conducting online assessments. The results also showed that the professors had difficulties in switching to online teaching. This study was significant in that it produced empirical data about online teaching based on the experiences of engineering college professors teaching classes online.

• Kyungpook Mathematical Journal
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• v.61 no.1
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• pp.61-74
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• 2021

Let G = (V, E) be a connected graph. The eccentric connectivity index of G is defined by ��C (G) = ∑u∈V (G) deg(u)e(u), where deg(u) and e(u) denote the degree and eccentricity of the vertex u in G, respectively. In this paper, we introduce a new formulation of ��C that will be called the distance eccentric connectivity index of G and defined by $${\xi}^{De}(G)\;=\;{\sum\limits_{u{\in}V(G)}}\;deg^{De}(u)e(u)$$ where degDe(u) denotes the distance eccentricity degree of the vertex u in G. The aim of this paper is to introduce and study this new topological index. The values of the eccentric connectivity index is calculated for some fundamental graph classes and also for some graph operations. Some inequalities giving upper and lower bounds for this index are obtained.