• Journal of Intelligence and Information Systems
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• v.16 no.1
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• pp.93-116
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• 2010

Ensemble approach is applied to the detection modeling of illegal cash accommodation (ICA) that is the well-known type of fraudulent usages of credit cards in far east nations and has not been addressed in the academic literatures. The performance of fraud detection model (FDM) suffers from the imbalanced data problem, which can be remedied to some extent using an ensemble of many classifiers. It is generally accepted that ensembles of classifiers produce better accuracy than a single classifier provided there is diversity in the ensemble. Furthermore, recent researches reveal that it may be better to ensemble some selected classifiers instead of all of the classifiers at hand. For the effective detection of ICA, we adopt ensemble size reduction technique that prunes the ensemble of all classifiers using accuracy and diversity measures. The diversity in ensemble manifests itself as disagreement or ambiguity among members. Data imbalance intrinsic to FDM affects our approach for ICA detection in two ways. First, we suggest the training procedure with over-sampling methods to obtain diverse training data sets. Second, we use some variants of accuracy and diversity measures that focus on fraud class. We also dynamically calculate the diversity measure-Forward Addition and Backward Elimination. In our experiments, Neural Networks, Decision Trees and Logit Regressions are the base models as the ensemble members and the performance of homogeneous ensembles are compared with that of heterogeneous ensembles. The experimental results show that the reduced size ensemble is as accurate on average over the data-sets tested as the non-pruned version, which provides benefits in terms of its application efficiency and reduced complexity of the ensemble.

• Korean Journal of Ecology and Environment
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• v.57 no.3
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• pp.123-133
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• 2024

To analyse the relationship between above-ground carbon stocks, species diversity and broadleaved forests structural diversity of South Korean forests, we collected vegetation inventories from environmental impact assessment projects over the past 10 years. The available data were selected and organised including tree species, DBH and area each projects. The data was classified by forest type, aboveground carbon stocks were calculated and compared, and the correlation between aboveground carbon stocks and biodiversity and structural diversity was analysed. The results showed that above-ground carbon stocks were higher in mixed forests and broadleaved forests and lower in needleleaved forests, similar to previous studies. However aboveground carbon stocks of mixed forests were higher in natural forests than in plantations. Aboveground carbon stocks in broadleaved forests were higher in plantations than natural forests, and there was no statistical different of between natural and plantations in needleleaved forest. This could be the result of a variety influences including biological and environmental factors in the study area, and further research is needed to analyse the effects on carbon sequestration. Correlation analysis showed no correlation between biodiversity and above-ground carbon stocks, but a positive correlation between structural diversity and above-ground carbon stocks. This indicates that above-ground carbon stocks in forests are associated with unevenness diameters and the proportion and evenness of tree species by diameter. In addition, it has been analysed that the high succession stages in forest have higher species diversity and structural diversity, and greater efficiency in the utilization of resources required for plant growth, leading to increased plant productivity and storage. Considering that the study sites were young forests with an average DBH of 14.8~23.7 cm, it is expected that carbon stocks will increase as biodiversity and structural diversity increase. Further research is needed to develop techniques to quantitatively assess the relationship of diversity to carbon stocks for policy use in assessing and increasing carbon stocks in forests.

• Journal of the Korean Society of Clothing and Textiles
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• v.24 no.4
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• pp.451-462
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• 2000

This study is to investigate the current use of POS system in Korean clothing industry, so that we can make suggestions for better use of it. We interviewd companies using POS systems as well as EAN Korea which is in charge of POS data processing. As a results. we found out that standard KAN code has severe difficulties to cope with the diversity of the information which is necessary in clothing industry. Therefore we are making some suggestions to use KAN code as a recognizing code for more structured master data file for extremely diverse clothing items.

• ETRI Journal
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• v.22 no.4
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• pp.1-12
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• 2000

Designing a reliable multicast-based network that scales to the size of a multicast group member is difficult because of the diversity of user demands. The loss inferences of internal nodes by end-to-end measurements do not require the use of complete statistics because of the use of maximum likelihood estimation. These schemes are very efficient and the inferred value converges fast to its true value. In the theoretical analysis, internal delay estimation is possible but the analysis is very complex due to the continuity property of the delay. In this paper, we propose the use of a bottleneck location estimator. This can overcome the analytical difficulty of the delay estimation using the power spectrum of the packet interarrival time as the performance metric. Both theoretical analysis and simulation results show that the proposed scheme can be used for bottleneck location inference of internal links in scalable multicasting.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.89-107
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• 2006

With the increased importance of groupware in organizations, groupware acceptance is regarded as an important outcome in the efforts of firms to leverage the potential of this information technology in their business activities and strategies. Despite significant investments in groupware, considerable diversity exists in how well firms have been able to implement groupware and leverage the business value of groupware. This study identifies important factors influencing user acceptance of groupware by extending TAM(Technology Acceptance Model) which includes perceived control, intrinsic motivation, and concentration as well as perceived ease of use and perceived usefulness from original TAM. The proposed model is tested in an organization among 104 employees using previous research measurements. According to the findings from the study, the usage intention of groupware can be explained by intrinsic motivation, perceived control, perceived ease of use, and Perceived usefulness. However, it fails to explain the effect of concentration on the intention.

• Journal of Ecology and Environment
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• v.35 no.2
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• pp.79-89
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• 2012

This study was conducted with the intention of clarifying the effects of land-use types on a species of ground beetle's richness, abundance, and composition; the study focused on urban landscapes. We also selected the potential bioindicators classifying land-use types; eleven sites were selected from an urban landscape in Korea. Overall, land-use types in urban landscapes did not appear to cause significant decrease in species richness or the abundance of total ground beetle assemblage. According to habitat preferences, several land-use types and distances from the forest significantly affected the species richness and abundance, while the open-habitat species were not affected by these variables. Land-use types were classified into two major groups, forest and non-forest areas, based on ground beetle assemblage; several indicators, such as $Dolichus$ $halensis$ $halensis$ and subfamily Carabinae species, were of particular consideration. In conclusion, environmental change by anthropogenic disturbance can cause different effects on ground beetle assemblages, and forest specialists can be negatively affected.

• The Journal of the Korea Contents Association
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• v.6 no.8
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• pp.38-48
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• 2006

Paying attention to the fact that Korean traditional ink and color paintings are different in their use of colors this paper was intended to demonstrate outcomes from the difference in their painting style through specific paintings and thereby categorizing a broad range of oriental paintings into 4 types(Indian ink light color, middle color, deep color, present color) in accordance with the method of using colors, suggest directions that oriental color paintings should move toward in the future in the diversity of modem Paintings. Due to the characteristics of materials, oriental ink paintings, in style, are light in color within lines, which in return makes colors confined to a complimentary role in an overall picture, not having their unique color identity Nevertheless, there are some paintings that use dark colors, which is called moderate saturation. For such dark-color based paintings, colors play a key role, together with the characteristics of materials of color painting, as colors are used to express the most part of a picture. This study, thus, discusses the difference in the use of color depending on style on one hand, and examined the diversity of modem color paintings through specific works on the other hand, since a number of color paintings similar to western Painting in style have been created today. In such diversity, works that are being currently created should contribute to taking over the tradition and further develop oriental colors with modem aesthetic sensitivity. This paper is aimed to help to do harmonious works with traditional and modern paintings by studying and classifying varieties of colors

• Journal of Environmental Impact Assessment
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• v.28 no.6
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• pp.525-535
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• 2019

In this study, 49 major WCS(Wildlife Crossing Structure), including Baekdu-daegan, were evaluated for the effectiveness of WCS on using the daily average frequency index and diversity Index comparing the number of species that appear with the surrounding habitats. According to the analysis, the average use frequency of the entire WCS was 1.4 times, and the average number of WCS exceeded the average was 17 and 34.7 percent of the total. There were 18 WCS with the same number of habitats and species that appeared in the same area, or 36.7 percent of the total. The daily average use frequency and variety were all analyzed at 10 efficient WCS, accounting for 20.4 percent of the total. According to the results of an site survey on the compliance rate of 4 efficient WCS, the compliance rate of the Deoksanjae overpass was the best in location selection, specifications, vegetation cover and soil, fence. The results of this research will be used as basic data for the study of WCS effectiveness, including the improvement of functions of new and installed WCS.

• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.374-390
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• 2015

This study aimed to identify the insect diversity and forest in urban green space, which can determine the current status of the ecosystem and provide basic data and information required for conservation planning and sustainable use of the environment. For this study, we have surveyed insect diversity by habitat types in the botanic garden of Wonkwang University, Iksan, from September, 2010 to September, 2011. During the research period, a total of 209 species, 78 families and 10 orders were observed, including 10 exportable species, 1 species of Korean Red List, 2 climate-sensitive indicator species and 70 designated species. Among these taxonomic groups, Coleoptera (36.36 %) showed the highest diversity with 76 species, followed by Hemiptera (25.36 %) with 46 species, Diptera (11.48 %) with 24 species and Hymenoptera (7.66 %) with 16 species. As for the diversity by survey time, the largest number of species were observed in September 2010 (52 families, 105 species), followed by May 2011 (37 families, 87 species), July 2011 (50 families, 86 species), June 2011 (40 families, 80 species) and August 2011 (43 families, 73 species). Relatively low diversity was observed in September 2011 (38 families, 60 species), October 2010 (36 families, 52 species) and April 2011 (19 families, 29 species). As for the diversity by survey point, the highest diversity was observed in S4 (75 families, 186 species, 88.99 %), followed by S1 (41 families, 70 species, 33.49 %), S2 (41 families, 63 species, 30.14 %), and S3 (36 families, 59 species, 28.22 %). According to the community analysis, the survey area S4 (H'=3.344, RI=9.257) showed the highest numbers in diversity index (H') and richness index (RI) of insects and S1 (0.985) showed the highest species evenness index (EI). On the other hand, S3 showed the lowest numbers (H'=2.428, RI=4.307, EI=0.832) in every index. The insect fauna is closely associated with the plants and vegetation structure in the green space. Therefore, it is necessary to manage and maintain the urban green space to make it similar to the natural environment.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.4
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• pp.81-87
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• 2013

A grounding scheme is one of important parts in protection for safety of electrical installations. Terminologies are successively creating and gradually increasing due to diversity and external environments. The declaration and definition of terminologies concerning grounding are in disorder in several KS standards, electrotechnical provisions for electrical installations and electrotechnical guides related to electrical installations. There seem to be serious confusions in use among technicians and experts. In this paper, we proposed a new scheme and system to consistently use the technical terms concerning grounding described in KS standards and technical provisions. Different use examples and the present state of terminologies on grounding described in Korean documents such as KS IEC standards, technical provisions for electrical installations, consumer's electrical installation guide, and etc are investigated. Although the scope of this work is limited to examine the terminologies on grounding, it is expected that the proposed method could be contributed to the consistent use of terminologies in all areas in KS C IEC standards and technical provisions for electrical installations.