• Journal of Intelligence and Information Systems
• /
• v.18 no.4
• /
• pp.59-77
• /
• 2012

This study focuses on predicting which firms will increase capital by issuing new stocks in the near future. Many stakeholders, including banks, credit rating agencies and investors, performs a variety of analyses for firms' growth, profitability, stability, activity, productivity, etc., and regularly report the firms' financial analysis indices. In the paper, we develop predictive models for rights issues using these financial analysis indices and data mining techniques. This study approaches to building the predictive models from the perspective of two different analyses. The first is the analysis period. We divide the analysis period into before and after the IMF financial crisis, and examine whether there is the difference between the two periods. The second is the prediction time. In order to predict when firms increase capital by issuing new stocks, the prediction time is categorized as one year, two years and three years later. Therefore Total six prediction models are developed and analyzed. In this paper, we employ the decision tree technique to build the prediction models for rights issues. The decision tree is the most widely used prediction method which builds decision trees to label or categorize cases into a set of known classes. In contrast to neural networks, logistic regression and SVM, decision tree techniques are well suited for high-dimensional applications and have strong explanation capabilities. There are well-known decision tree induction algorithms such as CHAID, CART, QUEST, C5.0, etc. Among them, we use C5.0 algorithm which is the most recently developed algorithm and yields performance better than other algorithms. We obtained data for the rights issue and financial analysis from TS2000 of Korea Listed Companies Association. A record of financial analysis data is consisted of 89 variables which include 9 growth indices, 30 profitability indices, 23 stability indices, 6 activity indices and 8 productivity indices. For the model building and test, we used 10,925 financial analysis data of total 658 listed firms. PASW Modeler 13 was used to build C5.0 decision trees for the six prediction models. Total 84 variables among financial analysis data are selected as the input variables of each model, and the rights issue status (issued or not issued) is defined as the output variable. To develop prediction models using C5.0 node (Node Options: Output type = Rule set, Use boosting = false, Cross-validate = false, Mode = Simple, Favor = Generality), we used 60% of data for model building and 40% of data for model test. The results of experimental analysis show that the prediction accuracies of data after the IMF financial crisis (59.04% to 60.43%) are about 10 percent higher than ones before IMF financial crisis (68.78% to 71.41%). These results indicate that since the IMF financial crisis, the reliability of financial analysis indices has increased and the firm intention of rights issue has been more obvious. The experiment results also show that the stability-related indices have a major impact on conducting rights issue in the case of short-term prediction. On the other hand, the long-term prediction of conducting rights issue is affected by financial analysis indices on profitability, stability, activity and productivity. All the prediction models include the industry code as one of significant variables. This means that companies in different types of industries show their different types of patterns for rights issue. We conclude that it is desirable for stakeholders to take into account stability-related indices and more various financial analysis indices for short-term prediction and long-term prediction, respectively. The current study has several limitations. First, we need to compare the differences in accuracy by using different data mining techniques such as neural networks, logistic regression and SVM. Second, we are required to develop and to evaluate new prediction models including variables which research in the theory of capital structure has mentioned about the relevance to rights issue.

• Economic and Environmental Geology
• /
• v.28 no.6
• /
• pp.613-621
• /
• 1995

It is understood that many big tungsten deposits such as the Sangdong in Korea, Fugigatami in Japan, Yukon in Canada, Pine Creek in U.S.A and Vostok in Russia were formed at late Cretaceous ages. However, most of tungsten mineralization in China where half the total world tungsten ores is reserved took place in late Jurassic to early Cretaceous ages. While the close association of molybdenum with tungsten mineralization is observed in the deposits related with Cretaceous magma, tungsten deposits in China related with late Jurassic to early Cretaceous show a close association of tin as well as molybdenum mineralization. It is characteristic that tungsten mineralization in China was followed by tin mineralization. The mode of occurrence of tungsten ore deposits in China is various and may represent the origin of tungsten in general, since the larger half of total amount of tungsten ores in the world are reserved in China. In case of Korea, more than 90% of total production of tungsten was occupied by the Sangdong tungsten deposit, which produced molybdenite as a byproduct Even if tin is detected in ppm unit content, no cassiterite is found in the Sangdong tungsten orebody. A similar type of two tungsten deposits is comparatively studied in order to confirm the published data; one is the Moping tungsten deposit in China and the other is the Dehwa tungsten deposit in Korea. Mineral assemblages occurring in quartz veins of both deposits are more or less same except that zinnwaldite and cassiterite occur only in the former deposit Ages of zinnwaldite and muscovite closely with molybdenite in the former deposit are 181.1 Ma and 167.8 Ma respectively, while muscovites associated with molybdenite in the latter deposit show ages of 80.9 Ma and 80.2 Ma. These results may represent deficient supply of tin from the source granitoid from which tungsten was derived in Korean peninsula during Cretaceous period, while tin supplied during tungsten mineralization tended to increase and the active tin mineralization followed the Jurassic tungsten mineralization in China.

• Journal of the Korean Regional Science Association
• /
• v.33 no.3
• /
• pp.61-78
• /
• 2017

Among several policies for industrial decentralization introduced since the 1960s, business relocation grant policies put a heavy financial burden on central and local governments. This study investigates the change in the likelihood of manufacturing establishments' relocation to the non-SMA associate with the change in business relocation grant policies. Using the mining and manufacturing survey data from 1996 to 2014, manufacturing firms' relocation decision model in nested logit structure was estimated. The data showed that the proportion of movements from the SMA to the non-SMA significantly increased after the introduction of the grant policies. However, estimation results of firms' relocation decision model indicated that the likelihood of firms relocating from the SMA to the non-SMA decreased after the introduction of the grant policies. In particular, firms' likelihood to move into the rural regions is even lower in the period of the grant extension. This suggests that increasing rate of relocations toward the rural regions may have been driven by the growing advantage of rural locations, such as low land rent and improvement in market accessibility, rather than the grants per se. This implies that the alleviation of physical and environmental constraints of the rural regions and the creation of business friendly environment such as easy access to premises at reasonable prices and strengthened linkage with the SMA, rather than simple provision of business relocation grants, needed to attract businesses in the rural regions.

• Journal of The Korean Association of Information Education
• /
• v.9 no.3
• /
• pp.453-462
• /
• 2005

Recently, due to technical improvements of storage devices and networks, the amount of data increase rapidly. In addition, it is required to find the knowledge embedded in a data stream as fast as possible. Huge data in a data stream are created continuously and changed fast. Various algorithms for finding frequent itemsets in a data stream are actively proposed. Current researches do not offer appropriate method to find frequent itemsets in which flow of time is reflected but provide only frequent items using total aggregation values. In this paper we proposes a novel algorithm for finding the relative frequent itemsets according to the time in a data stream. We also propose the method to save frequent items and sub-frequent items in order to take limited memory into account and the method to update time variant frequent items. The performance of the proposed method is analyzed through a series of experiments. The proposed method can search both frequent itemsets and relative frequent itemsets only using the action patterns of the students at each time slot. Thus, our method can enhance the effectiveness of learning and make the best plan for individual learning.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.3 no.2
• /
• pp.48-60
• /
• 2000

This study is aimed to clarify the distribution chracteristics of marine terraces and extract the specific surface at Gampo-eup, Gyeongju city on the map of 1:5,000 using GIS. The effects and problems occurred on the process of using GIS were investigated for the research of marine terrace. The longitudinal profile analysis was carried out along the 12 sections on the geomorphic surfaces of the study area, and actually High higher surface(HH-surface) was found over 100m a.s.l., which has not been reported till now. And the occupancy rate could be calculated by substitution on the height between 4m and 87m a.s.l. for each mean slope degree $1-5^{\circ}$ obtained from the actual measuring along four sections. Consequently the lower-I surface was highly reliable to use as the key bed for studying marine terraces. The accurate and detail analysis about the marine terraces is able to be accomplished on the basis of meaningful actual measuring, though its general possible distribution area can be extracted from GIS with the less effort. Namely the quantified results obtained from GIS could offer the basis for the objective analysis of the geomorphic surfaces. And we can look over the landscape and investigate the surfaces with reliefs effectively in relation to the real geomorphology on the study area, where in situ approach is difficult. But the digital map with a large scale should be offered first of all in order to raise the accuracy of the analysis.

• Journal of the Korean Association of Geographic Information Studies
• /
• v.17 no.3
• /
• pp.195-206
• /
• 2014

In this study, soil contamination maps related to Cu and Pb were created at the Busan abandoned mine in Korea using a handheld X-Ray Fluorescence(XRF) and Geographic Information Systems(GIS). Hydrological analysis was performed using the Digital Elevation Model(DEM) of the study area to identify the flow directions of surface runoff where pollutants can be dispersed from the soil contamination sources. 24 locations for measuring the soil contamination related to Cu and Pb were selected by considering the result of hydrological analysis. The results measured at the 24 locations using the handheld XRF showed that the highest value of Cu contamination is 8,255ppm and that of Pb is 2,146ppm. The field investigation data were entered into ArcGIS software, and then soil contamination maps regarding Cu and Pb with a 5m grid-spacing were created after performing spatial interpolations using the ordinary kriging method. As a result, we could know that high concentrations of Cu and Pb are presented at the waste and tailings dumps around the abandoned mine openings. This study also showed that the handheld XRF and GIS can be utilized to create soil contamination maps related to Cu and Pb in the field.

• Journal of Korean Home Economics Education Association
• /
• v.30 no.4
• /
• pp.93-112
• /
• 2018

We analysed the textbooks of Home Economics in middle school from 1^st to 2009 curriculums to investigate the contents and the portion of Food and Nutrition section. The key words were generated by word cloud technique using text-mining, and the portion of Food and Nutrition section was presented as a ratio of the pages. The core key words of Food and Nutrition section through the curriculums were 'raw food'·'food'·'diet'. In 1^st and 2^nd curriculums, the main key words were related to food materials, condiments and nutrients such as 'vitamin'·'protein'. The words such as 'nutrition'·'eating'·'requirement' were newly appeared in 3^rd, 'portion' in 6^th, and 'diet'·'adolescence' in 7^th curriculum. The mean ratio of Food and Nutrition section in Home Economics was 24.3%. While the portion was as high as 31.8% in 7th it was strikingly reduced to 15.2% in 2009^th. curriculum. Besides, Food and Nutrition section was composed of 10 units of middle level category during the 2^nd and 3^rd curriculums, and was reduced to 2 small units with none of middle level category in 2009^th curriculum. Although the contents of Food and Nutrition section has been developed and adapted to the needs of the society through the curriculums, the portion of Food and Nutrition section in Home Economics has been reduced especially in 2009^th curriculum, which could raise concerns on the health of individuals and communities.

• The Journal of the Korea Contents Association
• /
• v.11 no.6
• /
• pp.486-494
• /
• 2011

River bed change due to various factors in watershed and/or river environment would one of the most important issues in river management. To judge whether the river bed was aggrading or degrading, normally we use the change in thalweg or average bed, calculated using the design flood of the river. The present study is to figure out the problems of the existing methods and to propose a new concept of average river bed using annual maximum flood. To evaluate the new method, it was applied to the Nakdong River. We use the river bed data surveyed in 1983, 1993, and 2005. The results showed that there were no significant river bed change during 1983 and 1993, while the river bed was degraded significantly during 1993 and 2005. In the latter period, the river had severe degradations, 2~3 m in average sense and 5 m for the maximum in the middle reach(120~200 km from river mouth), and 1~2 m in average in the upper reach(200~240 km from river mouth). For the upstream reach of the confluence of the Naesung River(about 240 km from river mouth), most of the river bed change seemed to be only local phenomena. The main cause of the river bed change in the Nakdong River seems to be massive gravel mining in the middle reach of the river.

• The Journal of the Korea Contents Association
• /
• v.16 no.11
• /
• pp.253-263
• /
• 2016

We analyzed the social issue 'image of the elderly' using Big Data and Social Network Analysis. First, we analyzed the words extracted by the text mining technique by inputting the keyword 'elderly'. As a result of analysis, the image of the elderly viewed through media such as cafes, blogs, etc. Representing the trend of the public was using the word 'Senior' the most. The image of the elderly is expressed using the word having the highest frequency in the top 10, "The elderly are 'Senior' people who are respected by society, they are organized to earn money, to earn their qualifications, to health, and to 'Seniors' who desire to work healthy up to 100 years old". The purpose of this study is to differentiate from the existing analysis method by analyzing the macro-level image of the elderly including the social discourse by collecting vast amount of data and analyzing it with the social networking technique. When the image of the elderly that the public perceives is positively expressed as 'Senior', it can be said that the direction of the current elderly policy is evaluated as a desirable direction. On the other hand, it was able to feel the 'desire' of the public who wanted to be evaluated. Therefore, the policy direction of the elderly to be applied in the future should be the policy that enables the elderly to be perceived as 'Necessary existence' in society by taking on social roles. In addition, we proposed to implement the policy of the elderly that reflects priorities such as job creation, welfare, and alienation that can activity and maintain health.

• The Journal of the Korea Contents Association
• /
• v.8 no.1
• /
• pp.318-327
• /
• 2008

With the advance of information technologies and the spread of Internet use, the volume of usable information is increasing explosively. A content recommendation system provides the services of filtering out information that users do not want and recommending useful information. Existing recommendation systems analyze the records and patterns of Web connection and information demanded by users through data mining techniques and provide contents from the service provider's viewpoint. Because it is hard to express information on the users' side such as users' preference and lifestyle, only limited services can be provided. The semantic Web technology can define meaningful relations among data so that information can be collected, processed and applied according to purpose for all objects including images and documents. The present study proposes a content recommendation search system that can update and reflect personalized profiles dynamically in semantic Web environment. A personalized profile is composed of Collector that contains the characteristics of the profile, Aggregator that collects profile data from various collectors, and Resolver that interprets profile collectors specific to profile characteristic. The personalized module helps the content recommendation server make regular synchronization with the personalized profile. Choosing music as a recommended content, we conduct an experience on whether the personalized profile delivers the content to the content recommendation server according to a service scenario and the server provides a recommendation list reflecting the user's preference and lifestyle.