• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.18 no.4
• /
• pp.44-57
• /
• 2019

Various studies have been conducted to solve traffic congestions in many metropolitan cities through accurate traffic flow prediction. Most studies are based on the assumption that past traffic patterns repeat in the future. Models based on such an assumption fall short in case irregular traffic patterns abruptly occur. Instead, the approaches such as predicting traffic pattern through big data analytics and artificial intelligence have emerged. Specifically, deep learning algorithms such as RNN have been prevalent for tackling the problems of predicting temporal traffic flow as a time series. However, these algorithms do not perform well in terms of long-term prediction. In this paper, we take into account various external factors that may affect the traffic flows. We model the correlation between the multi-dimensional context information with temporal traffic speed pattern using deep neural networks. Our model trained with the traffic data from TOPIS system by Seoul, Korea can predict traffic speed on a specific date with the accuracy reaching nearly 90%. We expect that the accuracy can be improved further by taking into account additional factors such as accidents and constructions for the prediction.

• Journal of the Korea Convergence Society
• /
• v.10 no.3
• /
• pp.307-317
• /
• 2019

The purpose of this study was to identify the effect of person-environment fit and job embeddedness on turnover Intention. The subjects conveniently extracted 150 nurses who work at 2general hospitals in B and U metropolitan cities for more than six months, and Analyses were made using the SPSS WIN 20.0 and AMOS 21.0 programs to identify the causal relationship between person-job fit, person-organizational fit, person-supervisor fit, job embeddedness and turnover Intention. As a result, the variables with direct effect and total effect on job embeddedness showed personal-job fit, personal-organizational fit, person-supervisor fit and explained 76.3% of the job embeddedness. The most significant direct effect on turnover intention was job embeddedness and personal-job fit, personal-organizational fit, Person-supervisor fit showed indirect effect, and job embeddedness explained 36% of the turnover intention. In conclusion, if the personal-job fit, personal-organizational fit, and personal-superior fit of the clinical nurse are improved, the job embeddedness are improved turnover intention will decrease and the turnover rate will be decreased. In addition, it is necessary to study various factors affecting the turnover intention of person-environmental fit on nurses.

• 재활복지
• /
• v.20 no.4
• /
• pp.31-54
• /
• 2016

The purpose of this study is to explore the improvement method of the emergency safety system as a social protection scheme for the elderly living alone with severe disabilities. The study was conducted by randomly choosing three regions in the metropolitan area (Jongno-gu, Seoul), the small-medium city (Yongin-si, Gyeonggi-do) and the rural area (Geochang-gun, Gyeongsangnam-do) among 17 cities and counties nationwide. The study method is based on the interview form of the structured questionnaires with city officials, county officials, and center operators. According to the results of the interview analysis, it was recognized that there was a need for an emergency safety system for the elderly living alone with severe disabilities. In spite of this necessity, there were problems about publicity for the discovery of victims of the blind spot in welfare, about inconvenience due to frequent malfunctions of the emergency equipment, about insufficient awareness of the security of the emergency officials and about supply and demand of manpower for 24-hour monitoring service. In order to improve the effective operation of the emergency safety system, it was the most urgent issue to formulate the legislation for responding to the crisis management of the vulnerable. A suggestion of this study is to build a safety system in which one-stop service is provided for the realization of compact welfare through the establishment of a MOU for linkage with community organizations, the full inspection of emergency equipment to solve safety equipment malfunction problems and the manpower supplement for 24-hour monitoring.

• Journal of Climate Change Research
• /
• v.1 no.2
• /
• pp.109-120
• /
• 2010

Heat wave is a disaster, which increases morbidity and mortality in temperate regions. Climate model results indicate that both intensity and frequency of heat wave in the future will be increased. This study shows the result about relationship between excess mortality and offensive airmass in 7 metropolitan cities, and an operational Heat-Health Warning System (HHWS) in Korea. Using meteorological observations, the Spatial Synoptic Classification (SSC) has been used to classify each summer day from 1982 to 2007 into specific airmass categories for each city. Through the comparative study analysis of the daily airmass type and the corresponding daily mortality rate, Dry Tropical (DT), and Moist Tropical plus (MT+) were identified as the most offensive airmasses with the highest rates of mortality. Therefore, using the multiple linear regression, forecast algorithm was produced to predict the number of the excess deaths that will occur with each occurrence of the DT and MT+ days. Moreover, each excess death forecast algorithm was implemented for the system warning criteria based on the regional acclimatization differences. HHWS will give warnings to the city's residents under offensive weather situations which can lead to deterioration in public health, under the climate change.

• Korean Journal of Construction Engineering and Management
• /
• v.22 no.1
• /
• pp.27-35
• /
• 2021

The study intends to identify the effects of infrastructure property on an apartment house by analyzing the price variation affected by factors constituting the quality of the transit services of each individual station in urban railway system based on hedonic price model. The research findings indicate that the prices depending on the transit users have increased from 7.8% to 12.2% in Seoul and decreased from 6.1% to 12.9% in Gyeonggi, which implies that a lower number of transfer users has a positive effect on housing prices in Seoul unlike Gyeonggi. It also is noteworthy that the distance to the urban railway station had a negative effect on housing prices in Seoul and positive effect in Gyeonggi. Taking these results together, in Seoul, the increase in the number of transit users had a negative effect on neighborhood housing prices. When analyzed by segments, however, an additional negative effect was observed only in the apartments located within the radius of 100 meters. It is also found that the impact of transit users varies according to the regional characteristics, such as the density of commercial facilities and the population density, and the spatial extent of negative effect also showed regional differences. These results provide implications for the planning of new stations, new cities, and land use of existing areas around stations.

• Korean Journal of Community Nutrition
• /
• v.26 no.1
• /
• pp.48-55
• /
• 2021

Objectives: This study was conducted to estimate the dietary iodine intake of Koreans by a Total Diet Study (TDS) which provides 'closer-to-real' estimates of exposure to hazardous materials and nutrients through an analysis of table-ready (cooked) samples of foods. Methods: Dietary intake data from 2013-2017 Korea National Health and Nutrition Examination Survey (KNHANES) was used to select representative foods (RFs) for iodine analysis. A total of 115 RFs were selected and 158 'RF × cooking method-combination' pairs were derived by pairing each RF to corresponding cooking method(s) used more frequently. RFs were collected from 9 mega-markets in 9 metropolitan cities nationwide and mixed into composites prior to cooking preparation to a 'table ready' state for iodine analysis by inductively coupled plasma mass spectrometry. Iodine intake of Koreans was estimated based on the food intake data of the 2016-2018 KNHANES. Results: High iodine content was detected in seaweeds such as sea mustard and kelp. The mean iodine intake/capita/day was 418.4 ㎍ and the median value was 129.0 ㎍. Seaweeds contributed to 77.4% of the total iodine intake and the contribution by food item was as follows: sea mustard (44.0%), kelp (20.4%), laver (13.1%), milk (3.9%), egg (3.5%). Compared to the Dietary Reference Intakes for Koreans 2020, the proportion of people with iodine intake exceeding the tolerable upper intake level or below the estimated average requirement was high in the physiologically vulnerable groups (infants, children, pregnant women, and lactating women). Conclusions: The results, drawn from a TDS, are regarded closer to real estimates for iodine intake of Koreans compared with values in existing literature, which were based on a very limited variety of foods. On the other hand, it seems necessary to seek out solutions for the problematic iodine intake among physiologically vulnerable groups through in-depth analyses on food intake data collected with significant scale & quality.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.12
• /
• pp.52-59
• /
• 2020

Currently, the domestic electricity rates for houses are charged by applying a progressive level according to monthly electricity usage. Electricity rates rise sharply wWhen the amount of electricity used is large, electricity rates rise sharply. The standardized electricity rate progressive system has limitations in that it lacks consideration of the consumers' power usage patterns and limits consumers' their options. Accordingly, the Ministry of Trade, Industry and Energy and the Korea Electric Power Corporation have been demonstrating the basis of a rate system for housing, which is a method of charging electricity according to the amount of electricity used by season and time. In this paper, 10 electricity usage patterns were derived through from AMI data analysis for 5 five years of 362 apartment complexes located in metropolitan cities. The patterns were, and then applied to the existing domestic electricity rate and time-by-time rates applied to demonstrations, and by time-by-time rates in the US and Australia. The effect of the optional rate by pattern was compared and analyzed. As a result, it was confirmed that benefits occurred in five5 patterns compared to existing rate plans, and the electricity rates increased in 5 five patterns, and t. This phenomenon shows the same phenomenon withis the same as the overseas rates, including domestic rates being demonstrated.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.39 no.1
• /
• pp.29-40
• /
• 2021

Risk factors that threaten public safety such as crime, fire, and traffic accidents have spatial characteristics. Since each region has different dangerous environments, it is necessary to analyze the spatial pattern of risk factors for each sector such as traffic accident, fire, crime, and living safety. The purpose of this study is to analyze the spatial distribution pattern of local safety level index, which act as an index that rates the safety level of each sector (traffic accident, fire, crime, living safety, suicide, and infectious disease) for basic local governments across the nation. The following analysis tools were used to analyze the spatial autocorrelation of local safety level index : Global Moran's I, Local Moran's I, and Getis-Ord's G⁎i. The result of the analysis shows that the distribution of safety level on traffic accidents, fire, and suicide tends to be more clustered spatially compared to the safety level on crime, living safety, and infectious disease. As a result of analyzing significant spatial correlations between different regions, it was found that the Seoul metropolitan areas are relatively safe compared to other cities based on the integrated index of local safety. In addition, hot spot analysis using statistical values from Getis-Ord's G⁎i derived three hot spots(Samchuck, Cheongsong-gun, and Gimje) in which safety-vulnerable areas are clustered and 15 cold spots which are clusters of areas with high safety levels. These research findings can be used as basic data when the government is making policies to improve the safety level by identifying the spatial distribution and the spatial pattern in areas with vulnerable safety levels.

• Journal of Korean Library and Information Science Society
• /
• v.52 no.2
• /
• pp.45-64
• /
• 2021

This study compares the members of children's reading and culture movement organization versus general public and their children with the aim of understanding how parents' reading activities affect children's reading activities. The study surveyed 477 elementary school students and 483 parents from five special metropolitan cities regarding their reading behaviour. Reading behavior was investigated in terms of reading frequency, book selection information source, reading awareness, and preferred books, and it was confirmed that there was a difference between members of children's reading and culture movement organization and children of the general public. Members of children's reading and culture movement organization and their children showed superior reading habits in terms of both quantity and quality than non-members and their children, and the book selection information service was used. In terms of perception regarding reading, children's reading and culture movement organization members and their children found more "joy" in reading than "help in learning" as compared to the general public and their children. In terms of reading preference, children's reading and culture movement organization members and their children intensively preferred Korean creative fairy tales and picture books while the general public and their children preferred Korean creative fairy tales, picture books, and educational comics. In order to create a healthier reading culture and environment for the long term, the development of more active reading participation methods for the general public is required.

• Korean Journal of Environment and Ecology
• /
• v.35 no.6
• /
• pp.644-658
• /
• 2021

Understanding the functional traits of dominant species in urban ecosystems provides insight into species' trait adaptation and ecosystem function in response to fragmented and isolated urban vegetation and reduced biological interactions. This study compared means and variances of environmental factors (geographic, meteorological, and soil attributes) and 4 leaf traits (leaf area, specific leaf area, leaf dry mass content, and leaf shape index) and 7 reproductive traits (fruit width, fruit length, fruit shape, fruit dry weight, fruit dry matter content, seed weight, and seed ratio) measured of 40 Sorbus alnifolia individuals in four mountainous areas south of Seoul downtown, South Korea. We then performed the multivariate analysis of trait combinations. While the measured environmental factors indicated the individuality of the survey sites, the urban vegetation was drier and had a longer growth period. The leaves of S. alnifolia in the urban areas were smaller and heavier, and the fruits produced longer and lighter seeds, showing the traits affected by long urbanization. The study confirmed changes in the growth and reproduction mechanism of the S. alnifolia population under the urban environment, indicating reduced biological interaction due to vegetation fragmentation and isolation. This study provides limited but distinct ecological information about the function and persistence of key species in cities with a reduced scale of biological interactions and many negative environmental factors such as air pollution.