• Journal of Internet Computing and Services
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• v.22 no.3
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• pp.9-16
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• 2021

This study aims to develop a human activity recognition (HAR) system as a Deep-Learning (DL) classification model, distinguishing various human activities. We solely rely on the signals from a wristband accelerometer worn by a person for the user's convenience. 3-axis sequential acceleration signal data are gathered within a predefined time-window-slice, and they are used as input to the classification system. We are particularly interested in developing a Deep-Learning model that can outperform conventional machine learning classification performance. A total of 13 activities based on the laboratory experiments' data are used for the initial performance comparison. We have improved classification performance using the Convolutional Neural Network (CNN) combined with an auto-encoder feature reduction and parameter tuning. With various publically available HAR datasets, we could also achieve significant improvement in HAR classification. Our CNN model is also compared against Recurrent-Neural-Network(RNN) with Long Short-Term Memory(LSTM) to demonstrate its superiority. Noticeably, our model could distinguish both general activities and near-identical activities such as sitting down on the chair and floor, with almost perfect classification accuracy.

• Journal of Internet Computing and Services
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• v.21 no.4
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• pp.127-135
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• 2020

The purpose of this study is to develop a human activity recognition (HAR) system, which distinguishes 13 activities, including five activities commonly dealt with in conventional HAR researches and eight activities from the Eastern-Asian culture. The eight special activities include floor-sitting/standing, chair-sitting/standing, floor-lying/up, and bed-lying/up. We used a 3-axis accelerometer sensor on the wrist for data collection and designed a machine learning model for the activity classification. Data clustering through preprocessing and feature extraction/reduction is performed. We then tested six machine learning algorithms for recognition accuracy comparison. As a result, we have achieved an average accuracy of 99.7% for the 13 activities. This result is far better than the average accuracy of current HAR researches based on a smartwatch (89.4%). The superiority of the HAR system developed in this study is proven because we have achieved 98.7% accuracy with publically available 'pamap2' dataset of 12 activities, whose conventionally met the best accuracy is 96.6%.

• Korean Journal of Human Ecology
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• v.18 no.3
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• pp.689-703
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• 2009

The purpose of this study is to investigate the relationships among 'leisure constraints', 'leisure sufficiency' and 'life satisfaction' perceived by late middle-aged adults. The subjects of this research were 275 adults from 50 to 64. The results are as follows: 1) Among 5 categories of 'leisure constraints', the subjects perceive' financial constraints' as the most important, and in order of importance, 'social constraints', 'physical constraints', and 'familial constraints' followed. 2) Among five 'leisure activities', a factor perceived most sufficiently by middle-aged adults is 'simple relaxation' and followed by 'social activities', 'activities with family'. 'learning activities', and 'play-recreation activities'. 3) The factors influencing life satisfaction perceived by late-middle aged adults are 'religion', 'financial constraints', 'education', 'familial constraints', 'physical constraints', 'learning activities', and 'play-recreation activities'. These 7 factors explain 38.9% of total variation. Also, the 'leisure constraints' has a greater impact on their 'life satisfaction' than on their 'leisure sufficiency'.

• Journal of Families and Better Life
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• v.23 no.1 s.73
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• pp.31-39
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• 2005

This study was conducted to examine the meaning and motivation for family leisure activities, and to analyze how the family's attitude and motivation affect the satisfaction over family leisure activities. The participants of this study were sixty-five married couples who were living in Seoul. Sata were analyzed by frequency, mean, ANOVA, T-Test, and Duncan test. The major results of this research were as follows; first, there were statistically significant differences in the meanings the families attributed to, and motivations for, family leisure activities according to social-demographic characteristics (gender, age, education, job, and income and debt levels). Second, satisfaction over family leisure activities was affected by their meanings and motivations. The participants who participated voluntarily in family activities as 'leisure activities' showed a higher level of satisfaction.

• YAKHAK HOEJI
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• v.49 no.6
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• pp.505-510
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• 2005

Allylthio group of allicin and other organosulfur compounds which are isolated from garlic is considered as a pharmacophore, a key structure component of the molecule which is responsible biological activities. In the foregoing studies various 3-allylthio -6- alkoxypyridazine derivatives (K- compounds ) and 3-allylthio -6- alkylthiopyridazine derivatives(Thio-K-compounds) were synthesized and their biological activities were tested in vivo. They showed good hepatoprotective activities on the carbon tetrachloride-treated mouse and aflatoxin Bl-treated rat and chemopreventive activities on bepatocarcinoma cells in rat as expected. Now 3-allylthio-6-heterocyclylalkylaminopyridazine derivatives that the oxygen atom at 6-Position of 3-allylthio-6-alkoxypyridazine is replaced by nitrogen (N) were synthesiz ed and their activities were tested in vitro against SK-Hep-1 human liver cancer cells. They showed good chemopreventive activities on hepatocarcinoma cells.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.13-19
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• 2004

A bacterial expression vector for the human foamy virus (HFV) integrase was constructed and expressed in Escherichia coli. By two-step purification using a nickel-chelated column and a SP-sepharose chromatography; the HFV into-grase protein of 43 kDa was purified to near homogeneity, and used to investigate biochemical characteristics of the enzymatic activities, such as endonucleolytic and disintegration activities. Oligonucleotide substrates were specifically and efficiently cleaved by the purifed HFV integrase in the presence of Mn $^{+2}$, but not in the presence of Mg $^{+2}$, indicating that the HFV integrase is not able to use Mg $^{+2}$ as a cofactor Endonucleolytic reaction was almost completed in 60 min at 37 $^{\circ}C$. In addition, the maximum enzymatic activities were observed at 5 mM Mn $^{+2}$ in the buffer of which pH was from 7.0 to 9.0. The endonucleolytic activities were dose-dependently blocked in the addition of baicalein or chicolic acid which is a well-known inhibitor of human immunodeficiency virus integrase.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2018.06a
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• pp.45-46
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• 2018

This paper focuses on human activities monitoring problem using onboard smartphone sensors as data generator. Monitoring such activities can be very important to detect anomalies and prevent disease from patients. Machine learning (ML) algorithms appear to be ideal approaches to use for processing data from smartphone to get sense of how to classify human activities. ML algorithms depend on quality, the quantity and even more important, the properties or features, that can be learnt from data. This paper proposes a mobile virtual reality visualization system that helps to view data representation in a very immersive way so that its quality and discriminative characteristics may be evaluated and improved. The proposed system comes as well with a handy data collecting application that can be accessed directly by the VR visualization part.

• Journal of Korean Library and Information Science Society
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• v.48 no.3
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• pp.153-176
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• 2017

This article or study subjectively explores actual experiences of a human book from a phenomenal viewpoint and is based on considerable amounts of reference literature and the collecting/analyzing of precedent theses data. Selecting specific research samples and conducting in-depth interviews were made to elicit the phenomenal marks or responses in human book experiences. Samples included a total of three human book practicing teachers belonging to Gyonggi Provincial Office of Education, who were picked out or chosen according to their rich performance experiences/activities over a two year period. They were interviewed in four different basic topic areas or parts sectioned out to the following: 1) actual needs of a human book; 2) experiences in human book; 3) changes of cognition to the human book; and, lastly 4) improvement in the application of a human book. As a result, the number of schools, the number of readers, and the number of people who participated in human book activities continued to expand. In addition, human book activities have become an opportunity for growth not only for participating readers, but also for the human book itself.

• Korean Institute of Interior Design Journal
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• no.1
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• pp.67-71
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• 1992

This study analyse the quantitative relationships between the compositive factors of the residential interior space in the view point of physical aspects. The proposed analytical methods are focused on finding the quantitative relationships between the human dimensions of the static and dynamic life style situations and the compositive factors of the architectural interior spaces. As a result, the major analystical methods are ; the analysis of Space-human Body System for finding the quantitative relationships between the human dimensions and the order of architectural structures ; the analysis of Space-Objects-Human Body System for finding the quantitiative relationships between the human dimensions and furniture dimensions of the interior space ; the analysis of Space-Objects - Life Activities of Human Body System for finding the quantitative relation ships between the human dimensions of daily or non daily life activities including static furniture systems.

• Korean Journal of Pharmacognosy
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• v.30 no.2
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• pp.105-110
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• 1999

In our continuing search for new antineoplastic agents from natural products, one hundred and thirty-five herbal drugs were extracted with petroleum ether/ether (1:1), ethyl acetate and methyl alcohol, successively and their cytotoxicities were evaluated against A549 (human lung carcinoma) and SK-OV-3(human ovary adenocarcinoma) cell lines. Among them, fifteen kinds of ether extracts, eighteen kinds of ethyl acetate extracts and seven kinds of methanol extracts showed significant cytotoxic activities (above 70% inhibition) against A549 cell lines at a concentration of $40\;{\mu}g/ml,$ while ten kinds of ether extracts, thirteen kinds of ethyl acetate extracts and six kinds of methanol extracts demonstrated significant cytotoxic activities against SK-OV-3 cell lines at the above same concentration.