• Polymer(Korea)
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• v.29 no.6
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• pp.599-604
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• 2005

The hyaluronic acid (HA) with excellent biocompatibility has been combined with lactide, the ester dimer of polylactide, with good biodegradability to produce biocompatible materials which can control the period of degradation in a human body. By freeze frying method, HA and lactide were crosslinked with crosslinking agent, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC). Degree of lactide and EDC reaction was determined by the analysis of nuclear magnetic resonance spectroscopy. Both lactyl group and EDC conversion increased as the mole ratio of lactide to HA increased from 5 to 13. The membrane swelled less and became more brittle with the more addition of lactyl group resulting from the higher mole ratio of lactide to HA. Swelling ratio decreased and tensile modulus increased due to the more addition of lactyl group as the EDC concentration increased or reaction temperature decreased. Drug release experiment from various membranes with different degree of crosslinking showed that permeability decreased with increasing degree of crosslinking. The degradation became slower with the more addition of lactyl group. Mechanical property and degradation rate of the synthesized membrane were shown to be controlled through adjusting operation parameters such as mole ratio, temperature, and crosslinking agent concentration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4595-4600
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• 2014

A geoid has great meaning as a vertical reference plane, and at this point when GPS measurement is vitalized, it is an important factor that makes level measurements with GPS possible. This study carried out GPS and leveling of newly created complex control points targeting Daejeon. The geoid for the precise area was built by calculating the plane location, elevation and the geoid of each reference point using GPS/Leveling. In addition, this study evaluated the potential of GPS leveling throughout the site calibration. The geoid for the precise area intervals of approximately 1.5km throughout the study was determined. The results highlight the possibility of leveling by estimating direct leveling performance and mean altitude deviation by less than 2cm. Based on the results, if a geoid model for the precise and wide area can be developed throughout ongoing research, survey tasks that require elevation can be streamlined and the efficiency maximized.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.9
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• pp.1666-1672
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• 2016

In recent years, smart technology has been applied to various information system fields. Especially, traditional library service area is changing to Smart-Library from Digital-Library. In this environment are need to library service software platform for supporting variety content, library services, users and smart-devices. Due to this, existing library service has a limitation that inhibits semantic interoperability between different heterogeneous library systems. In this paper, we propose Linked-Open-Data based smart library as an archetype of future-library system that provide a variety content and system interaction and integration of services. It is an innovative system of the cutting-edge information intensive. Therefore, we designed system environments according to various integration requirements for smart library based on Linked-Open-Data. And, we describe the functional requirements of smart-library systems by considering the users' demands and the eco-systems of information technology. In addition, we show the reference framework, which can accommodate the functional requirements and provide smart knowledge service to user through a variety of smart-devices.

• Journal of the Korean Ceramic Society
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• v.41 no.9
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• pp.696-702
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• 2004

Lifetime of excited electronic states inside the 4f configuration of rare-earth elements embedded in chalcogenide glasses is very sensitive to medium-range structural changes of the host glasses. We have measured lifetimes of the 1.6$\mu\textrm{m}$ emission originating from Pr$\^$3+/ : ($^3$F$_3$, $^3$F$_4$)\longrightarrow$^3$H$_4$ transition in amorphous chalcogenide samples consisting of Ge, Sb, and Se elements. The measured lifetimes fumed out to have their maximum at the mean coordination number of -2.67, which arises accordingly from structural changes of the host glasses from 2 dimensional layers to 3 dimensional networks. This new finding supports that the so-called topological structure model together with chemically ordered network model is adequate to explain relationship between the emission properties of rare-earth elements and the medium-range structures of amorphous chalcogenide hosts with a large covalent bond nature. Thus, it is validated to predict site distribution and lifetime of rare-earth elements doped in chalcogenide glasses simply based on their mean coordination number.

• The Journal of Bigdata
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• v.1 no.2
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• pp.79-89
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• 2016

News organizations are looking for a way that can be reused accumulated intellectual property in order to find a new insights. BBC is a worldwide media that continually enhances the value of the news articles by using Linked Data model. Thus, utilizing the Linked Data model, by reusing the stored articles, can significantly improve the value of news articles. In this paper, we conducted a study of Linked Data construction for the healthcare news from a newspaper company. The object names associated with medical description or connected to other published information have been constructed into Linked Open Data service. The results of the study are to systematically organize the news data that were accumulated rashly, and to provide the opportunity to find new insights that could not be found before by connecting to other published information. It may be able to contribute to reused news data. Finally, using SPARQL query language can contribute to interactively searched news data.

• Culinary science and hospitality research
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• v.15 no.2
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• pp.45-56
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• 2009

The objective of this research is to provide serviced residence enterprises with the basic materials necessary for establishing a marketing strategy by surveying the recognition of service quality that differs according to the characteristics of customers using serviced residence. With 317 customers of the sample, the statistical data were treated by the frequency analysis, the reliability analysis, the analysis of searching factor, the t-test and the ANOVA. As a result, the service quality of serviced residence was divided into 5 factors of facilities, price, variety, reliability, expertise and kindness. Analyzing the difference in average for sex, nationality, marital status and natives and foreigners, it was found that there was significant difference in the variables of each factor. Considering the result of this research, it seems that serviced residence enterprises should enhance competitiveness with differentiated and specialized marketing strategies which satisfy the characteristics of customers.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.89-96
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• 2020

Linked Data allows structured data to be published in a standard way that datasets from various domains can be interlinked. With the rapid evolution of Linked Open Data(LOD), researchers are exploiting it to solve particular problems such as semantic similarity assessment. In this paper, we propose a method, on top of the basic concept of Linked Data Semantic Distance (LDSD), for calculating the Linked Data semantic distance between resources that can be used in the LOD-based recommender system. The semantic distance measurement model proposed in this paper is based on a similarity measurement that combines the LOD-based semantic distance and a new link weight using TF-IDF, which is well known in the field of information retrieval. In order to verify the effectiveness of this paper's approach, performance was evaluated in the context of an LOD-based recommendation system using mixed data of DBpedia and MovieLens. Experimental results show that the proposed method shows higher accuracy compared to other similar methods. In addition, it contributed to the improvement of the accuracy of the recommender system by expanding the range of semantic distance calculation.

• Journal of Korean Library and Information Science Society
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• v.48 no.3
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• pp.233-257
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• 2017

In this paper, we propose an effective method to convert and construct the MEDLINE, the world's largest biomedical bibliographic database, into linked data. To do this, we first derive the appropriate RDF schema by analyzing the MEDLINE record structure in detail, and convert each record into a valid RDF file in the derived schema. We apply the dual batch registration method to streamline the subject URI duplication checking procedure when merging all RDF files in the converted record unit and storing it in a single RDF triple storage. By applying this method, the number of RDF triple storage accesses for the subject URI duplication is reduced from 26,597,850 to 2,400, compared with the sequential configuration of linked data in units of RDF files. Therefore, it is expected that the result of this study will provide an important opportunity to eliminate the inefficiency in converting large volume bibliographic record sets into linked data, and to secure promptness and timeliness.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.15 no.1
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• pp.131-139
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• 1997

Geopotential models were used to determine the reference surface in geoid modelling and until now, OSU91A model has been most widely used in the world. But what so called EGM96, GSFC/DMA geopotential model published in the latter half of the 1996 by GSFC/DMA project. In this paper, we intended to compare the results of spherical harmonic analyses using the both geopotential model and the spherical harmonic analyses performed up to degree and order 300 and the gravimetric geoidal heights considering gravity data on each $3'\times{3'}$ grid point in and around Korean peninsula. The results showed that the average geoidal height of study area computed from EGM96 is larger 0.40 m than that computed from OSU91A and the gravimetric geoidal heights us-ing EGM96 is larger 0.35 m than that using OSU91A model.

• Journal of the Korean Society for information Management
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• v.30 no.1
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• pp.259-284
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• 2013

Public information has been collected in various fields with huge costs in order to serve public purposes such as public agencies' policy-making. However, the collected public information has been overlooked as silos. In korea, many attempts have been made to open the public information to the public only to result in limited extent, where OpenAPI data is being presented by some agencies. Recently, at the national level, the LOD(Linking Open Data) project has built the national DB, initiating the ground on which the linked data will be based for their active availability. This study has outlined overall problems in earlier projects which have built up national linking systems based on linked data for public data use. A possible solution has been proposed with a real experience of having set up an existing national DB of Korean public agencies.