• Journal of the Korean Institute of Gas
• /
• v.24 no.1
• /
• pp.17-22
• /
• 2020

Light Naphtha is distillated from crude oil unit and separated into the methane, ethylene and propylene by boiling point difference in sequence. This separation is conducted using a series of binary-like columns. This separation method is known that the energy consumed in the reboiler is used to separate the heaviest components and most of this energy is discarded as vapor condensation in the overhead cooler. In this study, the first two columns of the separation process are replaced with the Petlyuk column. A structural design was exercised by the stage computation with ideal tray efficiency in equilibrium condition. Compared with the performance of a conventional system of 3-column model, The design outcome shows that the procedure is simple and efficient because the composition of the liquid component in the column tray was designed to be similar to the equilibrium distillation curve. The performance of the new process indicates that an energy saving of 12.1% is obtained and the cost savings of 44 million won per day based on gross domestic product is reduced under same total number of trays and the initial investment cost is saved.

• KIPS Transactions on Software and Data Engineering
• /
• v.10 no.9
• /
• pp.359-366
• /
• 2021

A number of construction companies in Korea invest considerable human and financial resources to construct a system for managing apartment defect data and for categorizing repair tasks. Thus, this study proposes machine learning models to automatically classify defect complaint text-data into one of the sub categories of 'finishing work' (i.e., one of the defect repair tasks). In the proposed models, we employed two word representation methods (Bag-of-words, Term Frequency-Inverse Document Frequency (TF-IDF)) and two machine learning classifiers (Support Vector Machine, Random Forest). In particular, we conducted both binary- and multi- classification tasks to classify 9 sub categories of finishing work: home appliance installation work, paperwork, painting work, plastering work, interior masonry work, plaster finishing work, indoor furniture installation work, kitchen facility installation work, and tiling work. The machine learning classifiers using the TF-IDF representation method and Random Forest classification achieved more than 90% accuracy, precision, recall, and F1 score. We shed light on the possibility of constructing automated defect classification systems based on the proposed machine learning models.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.38 no.6
• /
• pp.887-894
• /
• 2018

An electric vehicle is emerging as an alternative to the response of global climate change and sustainability. However, an Electric vehicle has not been popular due to the constraints such as its price or technical limitations. In order to analyze the effect of purchasing electric vehicles, this study conducted a binary logistic regression model that demonstrates the relation between purchasing and influencing variables. Variables which have high correlation were excluded from the model through the correlation analysis to prevent multicollinearity. Socio-economic variables such as the number of owned vehicles, sex, ages are not significant. On the other hand, Variables related to prices, charging and policy are found to have a significant to effect on the purchase of electric vehicles. In accordance with the model estimated result, it seems to be necessary to improve the charging incentives, or to provide electric car information and to expand opportunities for experience electric vehicles. The result is also expected to be helpful for spreading electric vehicles and formulating policies.

• The Journal of Internal Korean Medicine
• /
• v.43 no.4
• /
• pp.542-558
• /
• 2022

Objectives: The purpose of this study was to assess the effect of Yigong-san on anorexia in children by conducting a systematic review and meta-analysis of randomized controlled trials (RCTs). Methods: Eleven electronic databases were searched on May 30, 2022 to collect relevant studies. All studies published up to the search date were considered. RCTs reporting the effect of Yigong-san on the treatment of anorexia in children were included. The primary outcome was an improvement in clinical anorexia symptoms after treatment. In this meta-analysis, continuous and binary outcomes were assessed, and the data were presented as the mean difference and risk ratio with their 95% confidence intervals. The risk of bias was assessed using the Cochrane Collaboration's risk of bias tool. Results: A total of nine studies were included in this systematic review. The treatment group (Yigong-san only or Yigong-san plus conventional treatment) showed a statistically significant effect compared to the control group (conventional treatment only) in total effective rate (Yigong-san only: RR 1.26, 95% CI 1.17, 1.36, I²=0%; Yigong-san plus conventional treatment: RR 1.32, 95% CI 1.18, 1.47, I²=0%), clinical symptoms, some of the anthropometric outcomes, and biological markers related to appetite and growth in children with anorexia. No serious adverse events related to Yigong-san were reported. Conclusions: Yigong-san showed statistically significant effects as a treatment for anorexia in children. However, the number of studies included in the meta-analysis was insufficient, and the herbs contained in the Yigong-san used in the included studies were not standardized. Future research should focus on the implementation of methodologically robust clinical research.

• Journal of Cadastre & Land InformatiX
• /
• v.51 no.2
• /
• pp.151-168
• /
• 2021

This study compared and analyzed the effect of the burden of household expenditure in the metropolitan and non-metropolitan areas on the intention to childbirth intention to married women using a panel logit model. To this end, this analysis targeted married women aged 25 to 39 who are highly likely to be fertile. The main results are as follows; First of all, it was confirmed that the economic power of spouse can be an important factor in the childbirth intention regardless of region. Second, it was found that the higher the satisfaction of marriage had a positive effect on the childbirth intention, and also higher the value that children must have, the higher the childbirth intention. Third, it was confirmed that the burden of household expenditure is the most important factor in the willingness to childbirth intention, excluding factors such as the number of existing children. In particular, the burden on education spending in both the capital region and non-capital region was found to be a key reason for the decrease in the childbirth intention. Lastly, the burden of household expenditure showed different effects on childbirth intention on depending on the region. Specifically, in the capital region, medical spending and loans had a greater impact, while, in the non-capital region, transportation and communication costs had a greater impact on childbirth intentions. Through the results, this study confirmed the implication that easing the burden on household expenditure is continuously necessary to enhance childbirth, and that discriminatory policy approaches are required depending on the area of residence.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.4
• /
• pp.27-37
• /
• 2019

This study empirically identified and sought implications for the degree of desire by film crews to participate in overseas production and the factors affecting them, based on the recognition that the active participation of skilled film crews in overseas production and joint ventures can be an alternative to the poor treatment of domestic film industry sites and the reduction of job losses due to problems with career barriers. In order for respondents to verify research questions, binomial logistic and marginal effects analysis using SPSS and STATA, the data obtained by surveying 402 film crews operating in various areas. The notable findings are as follow: First, about 65%(263 people) of the respondents expressed their desire to participate in overseas activity, indicating that a considerable number of film crews are looking forward to opportunities with overseas productions. Second, major factors that have a positive effect on film crews' need to participate in overseas activities have been found to be professionality, artistic identity, Korean Wave persistence, and career barriers. In other words, the higher the professionality, the more clearly the identity of the artist, the more positive expectations of the possibility of the Korean Wave continuing, and the more serious the problem of career disability, the clearer was the desire to participate in overseas production and joint-work activities.

• 한국노년학
• /
• v.30 no.4
• /
• pp.1145-1161
• /
• 2010

The objectives of this study were to examine how social networks of old retirees impact on their retirement satisfaction, and through this, to suggest ways of improving their retirement satisfaction. Data used in this study were from 2006 KLoSA(Korean Longitudinal Study of Ageing), which were collected from 1,009 elderly people aged 65 and over who resided metropolis and smaller medium cities and answered regarding their retirement satisfaction. Data were analyzed by Binary Logistic Regression method. As a result, the frequency of contact with children, the number of participation in their social activities, and the satisfaction of relationship with children were the significant variables to predict retirement satisfaction. In addition, other variables such as gender, subjective health status, type of retirement, and duration of past retirement have been found as significant variables to explain retirement satisfaction. Implications for designing effective retirement plan and service systems have been discussed.

• Journal of Internet Computing and Services
• /
• v.16 no.6
• /
• pp.89-95
• /
• 2015

Traditional frequent pattern mining discovers valid patterns with no smaller frequency than a user-defined minimum threshold from databases. In this framework, an enormous number of patterns may be extracted by a too low threshold, which makes result analysis difficult, and a too high one may generate no valid pattern. Setting an appropriate threshold is not an easy task since it requires the prior knowledge for its domain. Therefore, a pattern mining approach that is not based on the domain knowledge became needed due to inability of the framework to predict and control mining results precisely according to the given threshold. Top-k frequent pattern mining was proposed to solve the problem, and it mines top-k important patterns without any threshold setting. Through this method, users can find patterns from ones with the highest frequency to ones with the k-th highest frequency regardless of databases. In this paper, we provide knowledge both on frequent and top-k pattern mining. Although top-k frequent pattern mining extracts top-k significant patterns without the setting, it cannot consider both item quantities in transactions and relative importance of items in databases, and this is why the method cannot meet requirements of many real-world applications. That is, patterns with low frequency can be meaningful, and vice versa, in the applications. High utility pattern mining was proposed to reflect the characteristics of non-binary databases and requires a minimum threshold. Recently, top-k high utility pattern mining has been developed, through which users can mine the desired number of high utility patterns without the prior knowledge. In this paper, we analyze two algorithms related to top-k high utility pattern mining in detail. We also conduct various experiments for the algorithms on real datasets and study improvement point and development direction of top-k high utility pattern mining through performance analysis with respect to the experimental results.

• The Korean Society of Law and Medicine
• /
• v.19 no.2
• /
• pp.235-261
• /
• 2018

The Medical law stipulates regulations about the physician's duty to inform to contribute to patient's self-determination. This law was most recently revised on December 20, 2016, and came into effect on June 21, 2017. There has been much controversy about this, and it has been questioned whether or not it will be effective for physicians to comply with the duty to inform. Therefore, this study investigated perceptions of physicians of whether they observed the duty to inform and their legal judgment about that duty, and analyzed how the revision of the medical law may have affected the legal cognition of physician's duty to inform. This study was conducted through an online questionnaire survey involving 109 physicians over 2 weeks from March 29 to April 12, 2018, and 108 of the collected data were used for analysis. The questionnaire was developed by revising and supplementing the previous research (Lee, 2004). It consisted of 41 items, including 26 items related to the experience of and legal judgment about the duty to inform, 6 items related to awareness of revised medical law, and 9 items on general characteristics. The data were analyzed using SAS 9.4 program and descriptive statistics, Chi-square test, Fisher's exact test and Binary logistic regression were performed. The results are as follows. • Out of eight situations, the median number of situations that did not fulfill the duty to inform was 5 (IQR, 4-6). In addition, 12 respondents (11%) answered that they did not fulfill the duty to inform in all eight cases, while only one (1%) responded that he/she performed explanation obligations in all cases. • The median number of the legal judgment score on the duty to inform was 8 out of 13 (IQR, 7-9), and the scores ranged from a minimum of 4 (4 respondents) to a maximum of 11 (3 respondents). • More than half of the respondents (n=26, 52%) were unaware of the revision of the medical law, 27 (25%) were aware of the fact that the medical law had been revised, 20(18%) had a rough knowledge of the contents of the law, and only 5(5%) said they knew the contents of the law in detail. The level of awareness of the revised medical law was statistically significant difference according to respondents' sex (p<.49), age (p<.0001), career (p<.0001), working type (p<.024), and department (p<.049). • There was no statistically significant relationship between the level of awareness of the revised medical law and the level of legal judgment on the duty to inform. These results suggest that efforts to improve the implementation and cognition of physician's duty to inform are needed, and it is difficult to expect a direct positive effect from the legal regulations per se. Considering the distinct characteristics of medical institutions and hierarchical organizational culture of physicians, it is necessary to develop a credible guideline on the duty to inform within the medical system, and to strengthen the education of physicians about their duty to inform and its purpose.

• Journal of agricultural medicine and community health
• /
• v.48 no.2
• /
• pp.103-117
• /
• 2023

Objectives: This study aims to reveal the relationship between social relations and physical activity in the young-old and old-old elderly. Methods: Data from 2020 National survey of Older Koreans were used, and a total of 10,097 subjects over the age of 65 were included in analysis. The dependent variable was physical activity, and the independent variables were social relations barrier and motivational factors. x²-test and binary logistic regression were performed for data analysis. Results: The physical activity rate in the elderly were 40.8% in the young-old and 29.2% in the old-old. The socio-demographic characteristics affecting physical activity were the young-old elderly were sex, residential area, employment status and household income, and the old-old elderly were sex, age, residential area, education level and household income. The social relations barrier factors affecting physical activity were the young-old elderly were number of close friends, family care, exercise information search and video viewing, and the old-old elderly were household type, number of close friends, participation in exercise education, exercise information search and video viewing. The social relations motivational factors affecting physical activity were the young-old elderly were call with children/relative/friend, participation in sports activity, access time from home to parks, and the old-old elderly were call with children/relative/friend, participation in sports activity, satisfaction with green spaces. Conclusions: It was found that social relations barrier and motivational factors of the elderly are important factors to consider when developing physical activity promotion strategy, and there are also difference between the age of the elderly.