• Magazine of the Korea Concrete Institute
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• v.3 no.1
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• pp.71-78
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• 1991

Moleclar size distribution of three AC-20 asphalt cements were observed using high pressure - gel permeation chromatograph (HP-GPC). Bituminous concrete specimens were made using the asphalt cements and one aggre¬gate in laboratory to measure mechanical properties, tensile strength CIS) and resilient modulusCM,J. in dry and wet conditons. Results of mechanical property tests and profile of molecular size distribution of asphalt cements were analyzed to evaluate the relatonship of mechanical property with chromatogram. Regression analy¬sis showed a strong correlation between a mechanical property and sliced percent areas of chromatogram. Mathematical prediction models were developed based on the regression analysis. It was shown that characteris¬tics of asphalt cement chromatogram could be successfully used for estimation of selected mechanical property of asphalt concrete .

• Journal of Korea Multimedia Society
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• v.20 no.9
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• pp.1584-1595
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• 2017

Each cultural community has developed a variety of fonts to express their own language and characters. Hangul has also diversified its font shapes through changing the composition ratio and look of the consonants and vowels. Rather, thanks to the variety of these fonts, a considerable amount of time and effort must be devoted to the selection of a specific font shape. This is related to the fact that the current Hangul service and classification system process the font only with its name or the name of the manufacturer. It means that there is no consensus about the font shape classification system for Hangul. In this study, we propose a shape property set that can be a basis for classifying Hangul fonts. The font shape property set was generated by performing statistical analysis with features which have been studied by the font design experts and was verified through questionnaire using representative fonts based on the classification scheme defined by the Hangul font design classification system standard. This study is meaningful in that it is a study on shape classification properties of K-means and PCA statistical techniques based on font data rather than design field study.

• Korean Journal of Computational Design and Engineering
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• v.22 no.2
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• pp.118-128
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• 2017

Many countries have been developing BIM-based building code checking system and studies in the utilization of Industry Foundation Classes (IFC) in building code checking. IFC is the open standard of BIM format. Currently, there is a disadvantage that could not include all of the attribute for the regulations of each country and there is the problem with the interoperability of the different defined IFC approach between BIM software. This study focus on developing, derived object and property by comparing through domestic regulation and IFC2x3 specification provided by the buildingSMART and classified review type depending on the interoperability of derived information. According to classified review type, the IFC data structure was established and property mapping contents were developed by including BIM software compatible information and creating a type of review plan. When the developed property mapping contents are applied into BIM-based building code checking system, checking of the BIM data generated from various fields is made effective and thus improving the interoperability of information.

• Journal of the Ergonomics Society of Korea
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• v.34 no.5
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• pp.487-499
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• 2015

Objective: The purpose of this study was to analyze the trend of ergonomics field in overall intellectual property rights in Korea, and suggest the direction for the future development. Background: Many ergonomists are trying to pursue optimal human well-being and safety, and create more convenient designs for human use. For these reasons, intellectual property rights may be used to protect the legitimate rights of originative and innovative ergonomic designs. Method: Intellectual property rights were reviewed by using Korea Intellectual Property Rights Information Service (KIPRIS), and then were classified and analyzed according to three intellectual property rights (patent, utility model, design), International Patent Classification (IPC) and ergonomics application areas. Results: The total number of intellectual property rights registered in the ergonomics field in terms of three intellectual property rights (patent, utility model, design) showed 48,814 which occupied 5.97% of the total registered Korea's intellectual property rights. Within three intellectual property rights, patent (87%) was recorded overwhelmingly higher than utility model (9%) and design (4%). Conclusion: The current trend of patent, utility model and design in the ergonomics field in Korea tend to increase over time. It is suggested based on the analysis in this study that continuing research and development should be focused on electricity section in accordance with the global trend. Application: The results of this study can direct the ergonomists to the areas of intellectual property rights in the ergonomics field that should focus on the research and development in terms of three intellectual property rights, IPC and ergonomics application areas.

• Communications for Statistical Applications and Methods
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• v.24 no.6
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• pp.673-683
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• 2017

The least absolute shrinkage and selection operator (LASSO) has been a popular regression estimator with simultaneous variable selection. However, LASSO does not have the oracle property and its robust version is needed in the case of heavy-tailed errors or serious outliers. We propose a robust penalized regression estimator which provide a simultaneous variable selection and estimator. It is based on the rank regression and the non-convex penalty function, the smoothly clipped absolute deviation (SCAD) function which has the oracle property. The proposed method combines the robustness of the rank regression and the oracle property of the SCAD penalty. We develop an efficient algorithm to compute the proposed estimator that includes a SCAD estimate based on the local linear approximation and the tuning parameter of the penalty function. Our estimate can be obtained by the least absolute deviation method. We used an optimal tuning parameter based on the Bayesian information criterion and the cross validation method. Numerical simulation shows that the proposed estimator is robust and effective to analyze contaminated data.

• Elastomers and Composites
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• v.53 no.2
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• pp.67-74
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• 2018

Magneto-rheological elastomers (MREs) are smart materials in which the inherent stiffness and damping properties can be changed by the influence of an external magnetic field. The magneto-rheological (MR) effect depends on the orientation characteristics of the dispersed magneto-responsible particles (MRPs) in the matrix. In this study, natural rubber (NR) and ethylene propylene diene rubber (EPDM) were blended and used as a matrix of an MRE. EPDM was pre-cured before blending with NR. The Mooney viscosity, curing characteristics, and mechanical properties were analyzed with various pre-curing conditions of EPDM and the NR/EPDM blend. The results show that excellent mechanical properties of the NR/EPDM blend-based MRE were obtained when the pre-curing time of EPDM was 60 min. The aging property of the NR-based MRE was improved by the introduction of pre-cured EPDM. Also, the anisotropic MRE showed a higher MR effect than that of the isotropic MRE.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.4
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• pp.598-605
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• 2010

The structural design of oil tankers and bulk carriers should be performed based on the Common Structural Rules(CSR) which were recently established by the International Association Classification Societies(IACS). At first, in the structural design viewpoint, the scantling and hullweight based on the CSR should be compared with those of existing rules, and then a minimum weight/cost design should be performed by considering the variation of the number of web and the material property. In this study, the optimum web space and material property will be proposed by performing a minimum weight/cost design of a large oil tanker, and the results will be compared with those of existing ship. The longitudinal members are determined by SeaTrust-Holdan developed by the Korean Register of Shipping(KR), and the transverse members are determined by NASTRAN and PULS.

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.1
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• pp.120-127
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• 1999

The purpose of the study is to mae experimental whether the required property quantity and marker efficiency has variation of marking based on theoretical background of marking using th function of computer marking system. To investigate that variation of marking effect the required property quantity and marker efficiency as the following is tried to solve giving separation to item width of property cutting line detail which is believed to influence the required property quantity and marker efficiency. How to make experiment as follows separating in order marker of 1082 styles of women's ready-made clothes of with basic design(jacket. pants. skirt, two-piece). Then the data were subjected to analysis of variance and Duncan's multiple range test. The result of this studying as follows 1. In marker of women's jacket and pants the required property quantity shows lower when it is each item than when it is two-pice,. 2. In marker of women's pants marker efficiency shows the highest level when width is 132cm and it shows the lowest level when width is 112cm. 3. In width 152cm of skirt marker it has cutting lines shows lower the required property quantity than it doesn't have. 4. In marker of women's pants it has details shows more high marker efficiency than it doesn't have.

• The KIPS Transactions:PartC
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• v.12C no.7 s.103
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• pp.1057-1066
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• 2005

WebDAV(Web-based Distributed Authoring and Versioning), a protocol which supports web-based distributed authoring and versioning, provides a standard infrastructure for asynchronous collaboration on various contents through the Internet. A WebDAV property management is a function to set and manage the main information of the resources as properties, and a user property, one kind of the WebDAV properties, has the ability to be freely defined by users. This free definition of user property makes it very useful to develop web-based applications like a collaboration system based on WebDAV However, with an existing WebDAV property management scheme, there is a limit to develop various applications. This paper describes a DavUP(WebDAV User property design Protocol) protocol which extended the original WebDAV and its uti-lization which efficiently supports management of WebDAV user properties. DavUP needs the definition of the collection structure and type definition properties for an application. To do this, we added a new header md appropriated WebDAV method functions to the WebDAV protocol. To show the usefulness of DavUP protocols, we extended our DAVinci WebDAV server to support DavUP Protocols and experimentally implemented a general Open Workspace, which provides effective functions to share and exchange open data among general users, on the DAVinci.

• Korean Journal of Mathematics
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• v.29 no.3
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• pp.483-492
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• 2021

This article concerns the property that for any element a in a ring, if a²ⁿ = aⁿ for some n ≥ 2 then a² = a. The class of rings with this property is large, but there also exist many kinds of rings without that, for example, rings of characteristic ≠2 and finite fields of characteristic ≥ 3. Rings with such a property is called reduced-over-idempotent. The study of reduced-over-idempotent rings is based on the fact that the characteristic is 2 and every nonzero non-identity element generates an infinite multiplicative semigroup without identity. It is proved that the reduced-over-idempotent property pass to polynomial rings, and we provide power series rings with a partial affirmative argument. It is also proved that every finitely generated subring of a locally finite reduced-over-idempotent ring is isomorphic to a finite direct product of copies of the prime field {0, 1}. A method to construct reduced-over-idempotent fields is also provided.