• Korean Chemical Engineering Research
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• v.46 no.1
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• pp.23-36
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• 2008

Polymer-clay nanocomposites, a novel organic-inorganic hybrid, attract much attention from both scientific fields and engineering fields due to their balanced improvements in mechanical properties as well as diffusion behaviors, including flame-retarding and barrier properties, with small amounts of clay. Preparation of polymer-clay nanocomposites, summarized as a process for uniform dispersion of hydrophilic layered clays in hydrophobic polymer matrixes, includes several technologies and scientific phenomena, such as surface-modifications of clay layers, physical properties of clays in liquids and dried states, polymer synthesis, polymer rheology, behaviors of polymer solutions/or monomers in the confined geometry, mechanical properties of polymers and clays. To comprehend complicated physical/chemical phenomena involved in the fabrication of nanocomposites, we reviewed physical properties of clays, structures of clays in nanocomposites, characterization of nanocomposites, the relation between morphology and physical property of nanocomposites, surveyed recent research trends, and then suggested a few strategies or methods for fabrication of nanocomposites reflecting future research directions.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.647-659
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• 2008

Colloids are a heterogeneous system in which particles of a few nanometers to hundreds micrometers in size are finely dispersed in liquid medium, but show homogeneous properties in macroscopic scale. They have attracted much attention not only as model systems of natural atomic and molecular self-assembled structures but also as novel structural materials of practical applications in a wide range of areas. In particular, recent advances in colloidal science have focused on nano-bio materials and devices which are essential for drug discovery and delivery, diagnostics and biomedical applications. In this review, first we introduce nano-bio colloidal systems and surface modification of colloidal particles which creates various functional groups. Then, various methods of fabrication of colloidal particles using holographic lithography, microfluidics and virus templates are discussed in detail. Finally, various applications of colloids in metal inks, three-dimensional photonic crystals and two-dimensional nanopatterns are also reviewed as representative potential applications.

• Convergence Security Journal
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• v.13 no.1
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• pp.25-30
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• 2013

In this paper, the key performance index for advanced logistics is analyzed, and the specific requirements for the material flow IT services are proposed to improve the world competitiveness of the material flow industries and to implement the advanced logistics in Korea by survey research. The key performance index is classified into three types of efficiency, sustainability and economics, and two classes of enterprise and public for IT services are proposed. In addition to, for case studies, the survey analysis for the Pyeongtaek Port is performed to diagnose the material flow enterprise and to analyze the priorities of the IT services for Port's employee, trade enterprise, public service personnel, and local resident. From the results, to improve the productivity and efficiency of the enterprise, the secure the professional man-power and standardization are needed, and the automation, u-Port, green technology and material flow security for the IT services are required.

• Journal of the Korean School Mathematics Society
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• v.15 no.4
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• pp.699-718
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• 2012

The purpose of mathematics eduction is to develop the ability of thinking mathematically. It informs method to solve problem through mathematical thinking that teach mathematical ability. Errors in the problem solving can be thought as those in the mathematical thinking. Therefore analysis and classification of mathematics errors is important to teach mathematics. This study researches the preceding studies on mathematics errors and presents the characteristic of them with analyzed models. The results achieved by analysis of the process of problem solving are as follows : ▸ Students feel much harder to solve words problems rather than multiple-choice problems. ▸ The length of sentence make some differences of understanding of the words problems. Students easy to understand short sentence problems than long sentence problems. ▸ If students feel difficulties on the pre-learned mathematical content, they feel the same difficulties on the words problems based on the pre-learned mathematics content.

• Journal of Service Research and Studies
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• v.2 no.1
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• pp.69-80
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• 2012

The process and product types of the service business are various. Though the communication and sharing for learning about experience and knowledge are very important, but up to the present, the academic and systemic research have not been activated in this field. Recently, the demand and supply in the service business are growing rapidly, the related researches by the scientific and systemic approach are required. In this study, based on the research of Ostrom's team (2010) which described the category and suggestions on the service innovation issues, in the service implementation area, some research theme candidates, research trends, and examples are introduced. In service implementation area, three theme are introduced such as Effectively branding and selling services, Enhancing the service experience through co-creation, Measuring and optimizing the value of service. Finally to the service strategy, development and implementation planning scopes, the theme of leveraging technology to advance service can be applied commonly.

• Journal of the Korea Society of Computer and Information
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• v.15 no.5
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• pp.83-92
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• 2010

Along with the advance of industrial technology in mobile telecommunications and diversity in customer needs, today's Korean mobile telecommunication market has rapidly expanded due to stronger competition among businesses as well as increasing the number of subscribers. 3G roll-outs of mobile telecommunications service, so called "HSDPA" has seriously promoted marketing strategies among mobile telecommunication companies which led to move to the next generation customers. Understanding the competitive situation, mobile telecommunications companies are currently focusing on increasing sales per subscriber as well as increasing the number of subscribers as a solution to occupy the leading position in the mobile telecommunications industry in the future. The purpose of this study was to classify the customers in mobile telecommunications service with or without higher tendency of intention to subscribe and use the service using discriminant analysis. Through the discriminant analysis, discriminant function which classifying the critical user has been identified. The result of this study will give useful marketing strategies in competitive HSDPA mobile telecommunications market.

• Journal of the Korea Society of Computer and Information
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• v.15 no.8
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• pp.149-156
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• 2010

As following the development of the USN technology, sensor node used in sensor network has capability of quick data process and storage to support efficient network configuration is enabled. In addition, tree-based structure was transformed to cluster in the construction of sensor network. However, query processing based on existing tree structure could be inefficient under the cluster-based network. In this paper, we suggest energy efficient query processing mechanism using filtering through data attribute classification in cluster-based sensor network. The suggestion mechanism use advantage of cluster-based network so reduce energy of query processing and designed more intelligent query dissemination. And, we prove excellence of energy efficient side with MATLab.

• The Journal of Bigdata
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• v.5 no.1
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• pp.209-225
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• 2020

This study tried to establish a base level for the form of ginseng in order to prevent fraud in which novice consumers, who have no information on ginseng and mountain ginseng, regard ginseng as mountain ginseng. To that end, researchers designed a service design in which when a consumer takes a picture of ginseng with an APP dedicated to a smartphone, the photo is sent remotely and the determined results are sent to the consumer based on machine learning data. In order to minimize the difference between the data set in the research process and the background color, location, size, illumination, and color temperature of the mountain ginseng when consumers took pictures through their smartphones, the filming box exclusively for consumers was designed. Accordingly, the collection of mountain ginseng samples was made under the same controlled environment and setting as the designed box. This resulted in a 100% predicted probability from the CNN(VGG16) model using a sample that was about one-tenth less than widley required in machine learning.

• Journal of Digital Convergence
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• v.11 no.1
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• pp.423-430
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• 2013

The development of information technology introduced digital contents and Social Network Services(SNS), and allowed the virtual transaction and communication between users called "the experience knowledge" advanced from "the objective knowledge." This paper will analyze interactive storytelling system creating different types of stories on narrative genre about family history, personal history and so on. Through analysis on narrative interviews, direct observations, documentations and visual records, contents about CEO story, corporate story, family story and especially family history will be categorized into sampleDB and informationDB. Accumulated contents will allow the user to increase the value and usage of the contents through interactive storytelling system by restructuring the contents on family history. This research has developed writing tool data model using different digital contents such as texts, images and pictures to encourage open communications between first generations and third generations in Korea. Furthermore, researched about connected system on interactive storytelling creation device using various genre of family story that has been data based.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.213-222
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• 2017

This paper proposes a new service design which is deep learning-based image retrieval system for product search on O2O shopping mall platform. We have implemented deep learning technology that provides more convenient retrieval service for diverse images of many products that are sold in the internet shopping malls. In order to implement this retrieval system, real data used by shopping mall companies were used as experimental data. However, result from several experiments have confirmed deterioration of retrieval performance due to data components. In order to improve the performance, the learning data that interferes with the retrieval is revised several times, and then the values of experimental result are quantified with the verification data. Using the numerical values of these experiments, we have applied them to the new service design in this system.