• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1D
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• pp.195-202
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• 2006

The infiltration route analysis is a military application using geospatial information technology. The result of the analysis would present vulnerable routes for potential enemy infiltration. In order to find the susceptible routes, optimal path search algorithms (Dijkstra's and $A^*$) were used to minimize the cost function, summation of detection probability. The cost function was produced by capability of TOD (Thermal Observation Device), results of viewshed analysis using DEM (Digital Elevation Model) and two related geospatial information coverages (obstacle and vegetation) extracted from VITD (Vector product Interim Terrain Data). With respect to 50m by 50m cells, the individual cost was computed and recorded, and then the optimal infiltration routes was found while minimizing summation of the costs on the routes. The proposed algorithm was experimented in Daejeon region in South Korea. The test results show that Dijkstra's and $A^*$ algorithms do not present significant differences, but A* algorithm shows a better efficiency. This application can be used for both infiltration and surveillance. Using simulation of moving TOD, the most vulnerable routes can be detected for infiltration purpose. On the other hands, it can be inversely used for selection of the best locations of TOD. This is an example of powerful geospatial solution for military application.

• 한국노년학
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• v.39 no.4
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• pp.699-721
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• 2019

The purpose of this study was to examine and compare factors affecting the subjective life expectancy among the elderly, and to suggest health practice and social welfare service implications for later life. A total of 4,483 seniors from the 6th wave(2016) of the Korean Longitudinal Study on Aging (KLoSA) were used for analysis. The subjects were divided into three age groups: the young-old (n=2,106, 65~74 years), middle-old (n=1,803, 75~84 years), and oldest-old (n=574, 85 years and older). Control variables were sociodemographic factors and health status factors. Independent variables were health promotion behavior, cognition of public care, participating social activity, economic activity, and receiving basic pension. The data were analyzed using hierarchical multiple regression. The main results were as follows. Health promotion behavior was associated with the young-old. Social activities and economic activity were associated with the young-old and middle-old. Receiving basic pension had a significant impact on all age groups. In the middle-old, significant results were focused on socio-demographic and health status factors compared to other groups. The results of this study will provide basic data for the elderly policy and welfare service and will help to find and improve the important factors for the life of the elderly.

• Communications of Mathematical Education
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• v.37 no.3
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• pp.329-348
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• 2023

This study is necessary for the stable settlement of the 2022 revised mathematics curriculum 'data and possibility' area. This study was conducted centering on literature analysis. The purpose of this study is to realize statistics education in line with the 2022 revised mathematics curriculum. This purpose was achieved by examining the statistics learning contents of the 2022 revised curriculum, analyzing Chinese mathematics curriculum, and analyzing Chinese mathematics textbooks. In this study, the following studies were conducted. First, five elements were extracted through the analysis of the 'statistics and probability' area of the Chinese mathematics curriculum. The extracted elements are the 4th grade goals, synthesis and practice content areas, achievement standards for statistics and probability (6), (9), and (11). Second, examples presented in Chinese mathematics textbooks and Chinese curriculum appendices related to the extracted elements were analyzed. Regarding the 4th grade goal, the statistical problem-solving process of the 7th grade 2nd semester mathematics textbook was analyzed. Regarding the synthesis and practice content area, the data analysis unit of the 8th grade 2nd semester mathematics textbook was analyzed. In relation to the achievement standard (6), Example 85 of the curriculum appendix was analyzed, in relation to the achievement standard (9), Example 86 was analyzed, and in relation to the achievement standard (11), Example 87 was analyzed. Third, based on the analysis results, implications for the development of new curriculum and 'textbook development, teaching and learning methods' according to the 2022 revised middle school mathematics curriculum were derived. Through the results of this study, we expect the successful realization of the 2022 revised middle school mathematics and curriculum statistics education.

• Reproductive and Developmental Biology
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• v.37 no.1
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• pp.23-27
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• 2013

This study was carried out to investigate the influence of artificial insemination (AI) failure in 1,619 Korean native cows at Gangwon East area, Korea. The average AI failure rate was 37.02% in the cows and the highest rate was 40.85% in Yangyang-city. Based on the parity in the cows, the AI failure rate was 49.14% and 29.91% in the first and fifth parity cows, respectively. Whereas cows until fifth parity were decreased in AI failure, cows with sixth or more parity showed an upturning AI failure trends with the increasing of parity number. AI failure rate incidence according to the rump fat thickness measured by ultrasound was 28.9% and 33.4% at 5 mm to 10 mm and over than 15 mm, respectively. There was a positive correlation (0.2186) between AI failure rate of mother and that of their offspring cows. That is, offspring of dams with high AI failure rate showed also higher AI failure than those of dams having lower AI failure rate. In conclusion, these results indicate that the AI failure rate was closely related to the rump fat thickness, parity number, and conception rate of mother cows. In addition, these results might strengthen the basis to improve the reproductive performance in Korean native cows.

• Korea journal of population studies
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• v.26 no.2
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• pp.1-32
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• 2003

An analysis on cause-specific mortality at the provincial level provides essential information for policy formulation and makes it possible to draw hypotheses regarding various diseases and causes of death. Although the mortality level and causes of death at the provincial level are determined by the multiple effects of socioeconomic, cultural, medical and ecological factors, this study primarily intends to examine similarities and differences of cause-specific mortality at the provincial level. Utilizing the registered death and the registered population as of 1998, the delayed death registration and unreported infant deaths were supplemented at the provincial level and age-standardized death rates and life tables were calculated. Regarding the mortality level due to all causes, major findings were as follow: (1) For both sexes as a whole, Seoul showed the lowest mortality level, and Jeonnam showed the highest mortality level; and (2) The differences of the mortality level among provinces were greater for males than females and for those less than 65 years than those 65 years and over. Regarding the cause-specific mortality level revealed in all indicators (cause-specific age-standardized mortality rates and the probability of dying at birth due to a specific cause for males, females, and both sexes combined respectively), the major findings were as follow: (1) The mortality level due to heart diseases was the highest in Busan and the lowest in Gangweon; (2) The mortality level due to liver diseases was the highest in Chonnam; and (3) The mortality level due to traffic accidents was the highest in Chungnam and the lowest in Inchon. As the mortality differentials at the provincial level are related to various factors, exploratory statistical analysis is attempted for the 25 explanatory variables including socioeconomic variables and 90 mortality variables. Mortality due to all causes are related to socioeconomic variables. Among cause-specific mortality, mortality due to liver diseases and traffic accidents is related to socioeconomic variables. Finally, the need to improve the quality of death certificate is discussed.

• 한국노년학
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• v.36 no.4
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• pp.1003-1024
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• 2016

The human rights of older people have gotten more attention recently in South Korea, a country that is in transition to a super-aged society. This study aimed to systematically review studies on elder abuse and related factors among community-dwelling older adults in South Korea over twenty years (1994-2016). We searched major databases (Riss, DBpia, KISS, KMbase, and PubMed) and identified published studies relevant to the topic. Based on inclusion and exclusion criteria related to study quality, a total of 31 studies were selected for this review. We examined types, measurements, and risk factors of elder abuse as well as study designs in the selected studies, guided by Johannesen's theoretical framework on elder abuse. All of the reviewed studies on elder abuse in Korea were cross-sectional studies, most of which focused on older people living in urban areas, using a non-random sampling method. All of the studies focused on certain types of elder abuse only. Some adopted elder-abuse instruments that were not validated, and others used self-developed instruments without psychometric tests. As for the risk factors of elder abuse in South Korea, the physical and mental health of the victims and aggressors impacted the risk of elder abuse, but general sociodemographic factors such as age, sex, and education were less likely to be related to the risk. In addition, decreasing caregiver burden and building elder-friendly communities are important for the prevention of elder abuse. Needed are further empirical studies on elder abuse with a theoretical framework that gives consideration to the unique sociocultural contexts of Korea. It is also recommended to develop instruments to measure elder abuse reflecting the sociocultural contexts of Korea, and to examine the multi-dimensional risk factors of elder abuse.

• Journal of the Korean Society of Earth Science Education
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• v.15 no.3
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• pp.354-372
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• 2022

The purpose of this study is to explore the philosophical position of various scientific theories based on the scientific worldviews for science education. In addition, it aims to expand science education, which has usually dealt with epistemology and methodology, to ontology, that is, to the problem of metaphysics. It can be said that there exists a physical realism, traditionally defined as a strong determinism of the metaphysical belief. That is fixed and unchanging objective scientific knowledge independent of our minds, which was established by Newton, Einstein and Schridinger. What can be seen in the natural laws of dynamics can be called 'mathematicization'. Einstein also shook the traditional views to some extent through the theory of relativity, but his theory was still close to traditional thinking. On the contrary, to escape from this rigid determinism, we need anthropomorphic concepts such as 'possibility' and 'chance'. It is a characteristic of the modern scientific worldviews that leads the change of scientific theory from a classically strong deterministic thought to a weak deterministic accidental accident, probability theory, and a naturalistic point of view. This can be said to correspond to Darwin's theory of evolution and quantum mechanics. We can have three types of epistemological worlds that justify this ontological worldviews. These are rationalism, empiricism and naturalism. In many cases, science education does not tell us what kind of metaphysical beliefs the scientific theories we deal with in the field of education are based on. Also, science education focuses only on the understanding of scientific knowledge. However, it can be said that true knowledge can bring understanding only when it is connected to the knowledge of learned knowledge and the learner's own metaphysical belief in the world. Therefore, in the future, science education needs to connect various scientific theories based on scientific worldviews and philosophical position and present them to students.

• Korean Journal of Culture and Social Issue
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• v.12 no.5_spc
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• pp.99-116
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• 2006

This paper discuss adolescent's a quality of life related with risk behavior. The purpose of this study investigate to influence on risk behavior(runaway, smoking, sexual behavior) of the protective factors that moderate adolescent's problem behavior(delinquency). The assumption of this study that the protective factors counterbalance the negative influence of risk factors and finally, diminish a the problem behavior including a delinquent. A total of 1,020 students of a vocational high schook and a 216 adolescents of a special groups(the public institution that consisted with a delinquent young man) completed the questionnaires(risk behavior, 5 protective factors) of compiled by this researcher. The protective factors have selected based on the various prior studies analyzed with adolescent's risk behavior a family functioning, a father(a mother) each and child communication, a self efficacy, and a social support. Statistics appled for the data analysis are Chisqure analysis, two-way ANOVA, and Standard Discrimination analysis. The results of this study are as follows. First, the special group is higher than the general group in the rate of runaway, smoking, and sexual deviant behavior. Second, the protective factors are not action in the special group have experienced delinquency, but are only action in the general group consisted with the students of a vocational high schools. This means that the protective factors discriminating the participation of the risk behaviors, and blocking out the intervention of a problem behavior in the general adolescents. Although each protective factor influence to different according to each risk behavior, a role of a parent-child communication, a family functioning, and self-efficacy high orderly. Finally, discussed based on the previous studies that the protective factors moderate the negative influence of risk factors, offset the connection between a risk behavior and a. problem behavior, and improve and a resilience and the quality of life of the adolescents.

• Journal of Intelligence and Information Systems
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• v.23 no.4
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• pp.111-126
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• 2017

Recommender systems based on association rule mining significantly contribute to seller's sales by reducing consumers' time to search for products that they want. Recommendations based on the frequency of transactions such as orders can effectively screen out the products that are statistically marketable among multiple products. A product with a high possibility of sales, however, can be omitted from the recommendation if it records insufficient number of transactions at the beginning of the sale. Products missing from the associated recommendations may lose the chance of exposure to consumers, which leads to a decline in the number of transactions. In turn, diminished transactions may create a vicious circle of lost opportunity to be recommended. Thus, initial sales are likely to remain stagnant for a certain period of time. Products that are susceptible to fashion or seasonality, such as clothing, may be greatly affected. This study was aimed at expanding association rules to include into the list of recommendations those products whose initial trading frequency of transactions is low despite the possibility of high sales. The particular purpose is to predict the strength of the direct connection of two unconnected items through the properties of the paths located between them. An association between two items revealed in transactions can be interpreted as the interaction between them, which can be expressed as a link in a social network whose nodes are items. The first step calculates the centralities of the nodes in the middle of the paths that indirectly connect the two nodes without direct connection. The next step identifies the number of the paths and the shortest among them. These extracts are used as independent variables in the regression analysis to predict future connection strength between the nodes. The strength of the connection between the two nodes of the model, which is defined by the number of nodes between the two nodes, is measured after a certain period of time. The regression analysis results confirm that the number of paths between the two products, the distance of the shortest path, and the number of neighboring items connected to the products are significantly related to their potential strength. This study used actual order transaction data collected for three months from February to April in 2016 from an online commerce company. To reduce the complexity of analytics as the scale of the network grows, the analysis was performed only on miscellaneous goods. Two consecutively purchased items were chosen from each customer's transactions to obtain a pair of antecedent and consequent, which secures a link needed for constituting a social network. The direction of the link was determined in the order in which the goods were purchased. Except for the last ten days of the data collection period, the social network of associated items was built for the extraction of independent variables. The model predicts the number of links to be connected in the next ten days from the explanatory variables. Of the 5,711 previously unconnected links, 611 were newly connected for the last ten days. Through experiments, the proposed model demonstrated excellent predictions. Of the 571 links that the proposed model predicts, 269 were confirmed to have been connected. This is 4.4 times more than the average of 61, which can be found without any prediction model. This study is expected to be useful regarding industries whose new products launch quickly with short life cycles, since their exposure time is critical. Also, it can be used to detect diseases that are rarely found in the early stages of medical treatment because of the low incidence of outbreaks. Since the complexity of the social networking analysis is sensitive to the number of nodes and links that make up the network, this study was conducted in a particular category of miscellaneous goods. Future research should consider that this condition may limit the opportunity to detect unexpected associations between products belonging to different categories of classification.

• Journal of Intelligence and Information Systems
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• v.26 no.2
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• pp.27-42
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• 2020

Traditional companies with offline stores were unable to secure large display space due to the problems of cost. This limitation inevitably allowed limited kinds of products to be displayed on the shelves, which resulted in consumers being deprived of the opportunity to experience various items. Taking advantage of the virtual space called the Internet, online shopping goes beyond the limits of limitations in physical space of offline shopping and is now able to display numerous products on web pages that can satisfy consumers with a variety of needs. Paradoxically, however, this can also cause consumers to experience the difficulty of comparing and evaluating too many alternatives in their purchase decision-making process. As an effort to address this side effect, various kinds of consumer's purchase decision support systems have been studied, such as keyword-based item search service and recommender systems. These systems can reduce search time for items, prevent consumer from leaving while browsing, and contribute to the seller's increased sales. Among those systems, recommender systems based on association rule mining techniques can effectively detect interrelated products from transaction data such as orders. The association between products obtained by statistical analysis provides clues to predicting how interested consumers will be in another product. However, since its algorithm is based on the number of transactions, products not sold enough so far in the early days of launch may not be included in the list of recommendations even though they are highly likely to be sold. Such missing items may not have sufficient opportunities to be exposed to consumers to record sufficient sales, and then fall into a vicious cycle of a vicious cycle of declining sales and omission in the recommendation list. This situation is an inevitable outcome in situations in which recommendations are made based on past transaction histories, rather than on determining potential future sales possibilities. This study started with the idea that reflecting the means by which this potential possibility can be identified indirectly would help to select highly recommended products. In the light of the fact that the attributes of a product affect the consumer's purchasing decisions, this study was conducted to reflect them in the recommender systems. In other words, consumers who visit a product page have shown interest in the attributes of the product and would be also interested in other products with the same attributes. On such assumption, based on these attributes, the recommender system can select recommended products that can show a higher acceptance rate. Given that a category is one of the main attributes of a product, it can be a good indicator of not only direct associations between two items but also potential associations that have yet to be revealed. Based on this idea, the study devised a recommender system that reflects not only associations between products but also categories. Through regression analysis, two kinds of associations were combined to form a model that could predict the hit rate of recommendation. To evaluate the performance of the proposed model, another regression model was also developed based only on associations between products. Comparative experiments were designed to be similar to the environment in which products are actually recommended in online shopping malls. First, the association rules for all possible combinations of antecedent and consequent items were generated from the order data. Then, hit rates for each of the associated rules were predicted from the support and confidence that are calculated by each of the models. The comparative experiments using order data collected from an online shopping mall show that the recommendation accuracy can be improved by further reflecting not only the association between products but also categories in the recommendation of related products. The proposed model showed a 2 to 3 percent improvement in hit rates compared to the existing model. From a practical point of view, it is expected to have a positive effect on improving consumers' purchasing satisfaction and increasing sellers' sales.