• Journal of the Korean Association of Geographic Information Studies
• /
• v.26 no.3
• /
• pp.65-84
• /
• 2023

In order to establish a balanced development plan at the local government level, it is necessary to understand the current urban spatial structure. In particular, since the central area is a key element of balanced development, it is necessary to accurately identify its location and size. Therefore, the purpose of this study was to identify the central area system for Busan and to derive underprivileged areas that were alienated from the service areas where the functions of the central area could be used. To identify the central area system, four indicators(De facto Population, Land Price, Commercial Buildings, Credit Card Consumption) were used to calculate the central area index, and Getis-Ord Gi* and DBSCAN analysis were performed. Next, the hierarchy of the central areas were classified and the service areas were derived through network analysis by using it. As a result of the analysis, a total of 12 central areas were found in Seomyeon, Jungang, Yeonsan, Jangsan, Haeundae, Deokcheon, Dongnae, Daeyeon, Sasang, Pusan National University, Busan Station, and Sajik. Most of the underprivileged areas affected by the central area appeared in the Eastern area of Busan and the Western area of Busan, and were derived from old industrial areas, residential areas, and some new cities. Based on the results of the study, we can find three meanings. First, we have made a new attempt to apply a machine learning methodology that has not been covered in previous studies. Second, our data show the difference between the actual data and the existing planned central areas. Third, we not only found the location of the central areas, but also identified the underprivileged areas.

• Journal of Life Science
• /
• v.33 no.4
• /
• pp.325-333
• /
• 2023

This study compared and analyzed the microbial composition and physicochemical characteristics of kimchi (gimjang kimchi) and mukeunji (aged kimchi). Commercial kimchi and mukeunji products were purchased through an online market. After an analysis of physicochemical characteristics, the pH of the mukeunji samples was found to be lower and the acidity higher than in the kimchi samples. There was no significant difference in salinity between kimchi and mukeunji, but the sugar content was higher in the kimchi samples. The phylogenetic diversity index, which incorporates phylogenetic difference between species, was significantly higher in mukeunji than in the kimchi. The most dominant order in both groups was Lactobacillales, but several lactic acid bacteria, such as the Pediococcus and Lactobacillus species, which may be more acid tolerant or more competitive, are relatively predominant in mukeunji. Beta set-significance analysis based on two different distance metric results revealed that microbial distributions of population were different at the statistical confidence level (p<0.001). We investigated the effect of respective species on total microbial community using the LEfSe (linear discriminant analysis effect size) mechanism. According to the results of LEfSe testing, a relatively higher abundance of Weissella kandleri in kimchi and a higher abundance of Pediococcus inopinatus in mukeunji have the greatest influence on the differences in microbial structure between the two groups.

• Journal of Broadcast Engineering
• /
• v.27 no.1
• /
• pp.133-145
• /
• 2022

Compared to the continuously increasing dog population and industry size in Korea, systematic analysis of related data and research on breed classification methods are very insufficient. In this paper, an automatic breed classification method is proposed using deep learning technology for 14 major dog breeds domestically raised. To do this, dog images are collected for deep learning training and a dataset is built, and a breed classification algorithm is created by performing transfer learning based on VGG-16 and Resnet-34 as backbone networks. In order to check the transfer learning effect of the two models on dog images, we compared the use of pre-trained weights and the experiment of updating the weights. When fine tuning was performed based on VGG-16 backbone network, in the final model, the accuracy of Top 1 was about 89% and that of Top 3 was about 94%, respectively. The domestic dog breed classification method and data construction proposed in this paper have the potential to be used for various application purposes, such as classification of abandoned and lost dog breeds in animal protection centers or utilization in pet-feed industry.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.7 no.3
• /
• pp.31-41
• /
• 2017

Through the evolutionary process of the North Korean defector support policies, this research investigates the background behind the formation of non-profit organizations for the North Korean defectors and to identify and understand the problem through their characteristics and functions. Starting from 1990, with an increase in the North Korean Defectors' population as well as the introduction of multicultural society, various environmental factors, such as the domestic socio-environmental changes, resulted an increase in number of private organizations. However, not to mention the size and functions of the organizations, some do not even have required legal organizational structures in place. Their business activities, in some cases, are irrelevant to the original purpose and objectives. Moreover, the fact that 83% of the North Korean Defectors Organizations are based in Seoul while 25.5% of the North Korean Defector residing in Seoul, inevitably make the reputation of the organizations to be illegal and dishonest due to the excessive level of competitions among the similar types of organizations. In reality, the organizations show lack of growth in the areas such as securing necessary employments to the Defectors or providing educations to the youth, who will eventually become the future leaders, in building the awareness capacity toward the unification. These results show that, in conducting their activities, the organizations must be aware of the rights and responsibilities as the constituents of the society, plus the government's practical efforts in improving these issues are also necessary.

• Korean Journal of Ichthyology
• /
• v.34 no.4
• /
• pp.262-269
• /
• 2022

A distribution survey was conducted from 2018 to 2020 to evaluate the distribution status, habitat characteristics, and extinction threat of the short ninespine stickleback Pungitius kaibarae (Gasterosteidae). Literature reports of P. kaibarae distribution have been sorted by each period, 1980~1996, 1997~2005, and 2007~2017, and the samples were collected in 32, 43, and 64 stations for each period. Among the 75 streams and 193 sampling sites investigated during the study period, 1,400 P. kaibarae individuals were collected from 26 streams at 39 sites. The main habitat of P. kaibarae was downstream or brackish water zones with a low altitude, slow water velocity, and many aquatic plants. The main reasons for the decline in population size were assumed to be drought and flood, river work for flood restoration and river maintenance, bridges construction, and predation by the exotic fish species Micropterus salmoides. Previous evidence reported a 42.6% reduction in occupancy within 10 years, a decline in habitat quality, and the spread and impact of the exotic fish species Micropterus salmoides. Therefore, P. kaibarae is now considered a Vulnerable (VU A2ace) species based on the IUCN Red List categories and criteria. Therefore, P. kaibarae should be redesignated as an endangered species by the Ministry of Environment and systematically managed.

• 한국노년학
• /
• v.29 no.4
• /
• pp.1645-1663
• /
• 2009

The purpose of the study is to analyze the mediating effects of self-image on the relationship between experience of discrimination and self-esteem among the elderly in Korea. Furthermore, it is to explore whether these effects are moderated by social and economic activity participation. Data were collected from a cross-sectional survey of 543 community-dwelling Korean older adults (age≥65) drawn from community and senior centers in the mid-size city in Korea. The statistical analysis was performed by a structural equation modeling using LISREL statistical program. The results are fourfold. First, experiences of discrimination exerted the negative effects on physical, dispositional, and competent self-images of the elderly. Second, dispositional and competent self-image brought down by discriminative experiences lowered the levels of self-esteem. Third, social activity participation moderated the negative effects of discrimination experiences on physical and dispositional self-images. It also moderated the effects of dispositional self-image on self-esteem. Fourth, economic activity participation did not show moderating effects on the relationship between experience of discrimination and self-images. Meanwhile, it moderated the effect of competent self-image on self-esteem. These results demonstrate that to improve self-esteem of the elderly population, social welfare policies should make effort to reduce discrimination toward the elderly. Furthermore, social welfare organizations should also try to implement diverse community based programs geared for enhancing social and economic activities for elderly. Limitations and directions for future research are also discussed.

• Korean Journal of Legislative Studies
• /
• v.27 no.1
• /
• pp.5-40
• /
• 2021

This study attempts to analyze gender gaps in voter turnout for three different types of elections held since 2017 at the aggregate level using the Central Election Management Commission's turnout data, paying attention to the importance of women's voting. The findings are as follows. First, modern gender gaps in voter turnout at the aggregate level are confirmed in most regions regardless of election types. Second, the gender gap in turnout varies with age. The gender difference is verified in the "widowhood effect," where turnout decreases in the oldest-old. In the new voter group, modern gender gaps appear in most regions. The reversed gender difference in turnout in the late 20s, which reflects the Korean society's characteristics, is confirmed in all elections. Third, it is unclear whether the reverse gender gap in turnout becomes more pronounced in urbanized districts. As urbanization progressed, modern gender differences in voter turnout across age groups are observed at the population-based size level. Paradoxically, the modern gender gap tends to be weak and turns into the traditional gender gap in younger age groups (in the late thirties) in Gangnam-gu and Seocho-gu, the most modernized districts in Seoul. These results show that the modern gender gap in turnout is now a common phenomenon and continues to be strengthened by newly recruited voters in Korea. Thus we should pay more attention to female voters' political behavior and a new approach beyond the developmental theory to understand the causal mechanism to generate the modern gender gap in voter turnout.

• Korea Trade Review
• /
• v.48 no.2
• /
• pp.111-127
• /
• 2023

While the e-commerce market in Southeast Asia is growing, this study aims to derive factors for establishing an entry strategy for the Cambodian e-commerce market where Korean logistics companies can strategically enter in the future. Cambodia is a country where growth and growth potential in the e-commerce market is steadily increasing based on the high youth population ratio, high smartphone penetration rate, the introduction of convenient payment systems, and government-level e-commerce promotion policies. In this study, Korean logistics companies established detailed promotion strategies by deriving factors necessary for Cambodia's entry into the e-commerce market and analyzing their relative importance. The AHP analysis technique derived three top factors for the entry strategy, and each presented four sub-factors. As a result, the importance was shown in the order of 'Market Factor' (0.556), 'Policy and Institutional Factor' (0.295), and 'Corporate Competency Factor' (0.149). As a result of the sub-factors analysis, the importance was found in the order of "Characteristics and Growth Potential of Distribution Channel" (0.230), "Purchasing Power and Awareness Level of Consumers" (0.176), "Cambodia Government's E-commerce Policy and Institutional Support" (0.122), and "Cambodia Government's Logistics Infrastructure Plan" (0.108). In both the upper and lower factors, the characteristics and growth potential of the Cambodian e-commerce market were important, indicating that Korean logistics companies value market size and growth potential to enter the Cambodian e-commerce market. The results of this study can be used as a guideline to help Korean logistics companies make successful inroads into Cambodia, where the e-commerce market is expected to grow in the future.

• Korean Journal of Ichthyology
• /
• v.35 no.4
• /
• pp.270-277
• /
• 2023

Since its introduction in 1973, the bass, Micropterus salmoides, has spread to dams and rivers in Korea, adversely affecting native fish communities. In this study, after complete removal of bass from Bukchosan Reservoir, an farm reservoir that has lost its function, an attempt was made to indirectly confirm the adverse effects of bass on fish by comparing fish communities in reservoirs of a similar size where bass inhabit. The study was conducted three times a year from 2019 to 2022. As a result of the study, in Bukchosan Reservoir, where the species composition of fish was judged to be simplified due to the habitat of bass, only four species such as Carassius auratus and Rhinogobius brunneus that could be used as a food source for bass appeared before the removal of bass, but after the removal of bass. The appearance and increase of the population of the introduced small freshwater fish (Oryzias sinensis, Rhinogobius giurinus) were confirmed. When comparing Gangjeong Reservoir, Susim Reservoir, which are other reservoirs inhabited by bass investigated in this study, and Bukchosan Reservoir, this result is judged to show a trend of stabilization and recovery of fish species after removal of bass in small reservoirs with high predation pressure of bass.

• Information Systems Review
• /
• v.19 no.2
• /
• pp.115-136
• /
• 2017

Online communities have become substantial aspects of people's daily lives. However, only a few communities succeed and attract the majority of users, whereas the vast majority struggle for survival. When various communities coexist, important factors should be identified and examined to maintain attraction and achieve success. The concept of coexistence as been extensively explored in organizational ecology literature. However, given the similarities and differences between online communities and traditional organizations, the direct application of organizational theories to online contexts should be cautiously explored. In this study, we follow the roadmap proposed by Davis et al. (2007) in conducting agent-based modeling and simulation study to develop a novel theory based on the previous literature. In the case of two coexisting communities, we find that community size and participation costs can significantly affect the development of a community. A large community can attract a high number of active members who frequently log in. By contrast, low participation costs can encourage the reading and posting behaviors of members. We also observe the important influence of the distribution of interests on the topic trends of communities. A community composed of a population that focuses on only one topic can quickly converge on the topic regardless of whether the initial topic is broad or focused. This simulation model provides theoretical implications to literature and practical guidance to operators of online communities.