• Journal of the Korea Society of Computer and Information
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• v.25 no.8
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• pp.9-21
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• 2020

With the proliferation of RDF knowledge graphs(KGs), there arose a need of a standardized schema representation of the graph model for effective data interchangeability and interoperability. The need resulted in the development of SHACL specification to describe and validate RDF graph's structure by W3C. Relational databases(RDBs) are one of major sources for acquiring structured knowledge. The standard for automatic generation of RDF KGs from RDBs is R2RML, which is also developed by W3C. Since R2RML is designed to generate only RDF data graphs from RDBs, additional manual tasks are required to create the schemas for the graphs. In this paper we propose an approach to automatically generate SHACL schemas for RDF KGs populated by R2RML mappings. The key of our approach is that the SHACL shemas are built only from R2RML documents. We describe an implementation of our appraoch. Then, we show the validity of our approach with R2RML test cases designed by W3C.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.8
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• pp.1698-1707
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• 2003

These days, XML is accepted and used to e commerce market broadly. But by reason of XML document can exist same form logically but several other forms physically, several problems can happen in application that judge effectiveness as physical form such as XML digital signature. Therefore, it is recommending to propose and use canonical XML algorithm to change identical XML document physically equally logically in W3C to solve this problems. We implemented system that nm Canonical XML algorithm that suggested in W3C that can change to mon elaborate regular document. Thus, interoperable with other application that takes W3C recommendation Also, as well as use in digital signature system for web service is useful, use in several system that physical identify is required when it exchanges na document for web service interoperability are considered to be valuable. Moreover, Adding the transformation ability between universal encoding scheme and EUC­KR that is internal encoding scheme should be Canonical XML Algorithm that is suited to internal circumstances, and this should be a foundation technique of international interoperability confirmedness.

• Korean Journal of Materials Research
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• v.11 no.11
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• pp.953-959
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• 2001

Homogeneous spherical W-Co salt powders were made by spray drying of aqueous solution of ammonium $metatungstate(NH_4)_6(H_2W_{12}O_{40}){\cdot}4H_2O,\; AMT)$ and cobalt nitrate $hexahydrate(Co(NO_3)_2{\cdot}6H_2O)$. The thermal decomposition process of spray dried W-Co salt powders was studied by TG, XRD, SEM, TEM and FT-IR. Spray dried W-Co salt powders were calcined for 1 hour in the temperature from$ 350^{\circ}C$ to $800^{\circ}C$ in atmosphere of air. At the temperatures over $600^{\circ}C$, spherical $CoWO_4/WO_3$ composite oxide powders were obtained. The primary particle size of W/Co composite oxide powders increased with increasing thermal decomposition temperature due to the particle growth. The observed crystallite size by TEM was in the range of 60nm and that of $CoWO_4$ calculated by Scherrer's formula at $800^{\circ}C$ was smaller than 55nm. The crystallite site was identified by XRD and TEM.

• Korean Journal of Microbiology
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• v.52 no.3
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• pp.254-259
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• 2016

Acinetobacter sp. B-W producing siderophore, 2, 3-dihydroxybenzoic acid (DHB) was analyzed for plasmid content. Strain B-W harbored plasmid of 20 kb in size. Growth at $43^{\circ}C$ was effective in producing mutant cured of plasmid of strain B-W. This mutant lost the ability to produce 2, 3-DHB. Formation of siderophore halos on the chrome azurol S (CAS) agar medium was not detected by cured strain B-W. pHs of supernatants of wild type strain B-W and cured mutant grown in glucose and $MnSO_4$ containing medium at $28^{\circ}C$ for 3 days were 4.5 and 8.5, respectively. Antibiotic resistance against ampicillin, actinomycin D, bacitracin, lincomycin, and vancomycin was lost in cured mutant. Plasmid curing of strain B-W resulted in drastic reduction of minimal inhibitory concentration (MIC) of several antibiotics. E. coli $DH5{\alpha}$ was transformed with plasmid isolated from strain B-W. The transformant E. coli $DH5{\alpha}$ harbored a plasmid of the same molecular size as that of the donor plasmid. Transformant E. coli $DH5{\alpha}$ produced 2, 3-DHB and contained antibiotic resistant ability. Thus a single plasmid of 20 kb seemed to be involved in 2, 3-DHB production. Genes encoding resistance to antibiotics were also supposed to be located on this plasmid.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.609-610
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• 2008

In this paper, a 110 dB, 1.024 MHz fourth-order single-loop Delta-Sigma sigma modulator has been presented with an over-sampling ratio of 128 and an overload factor of -6 dB for a bandwidth of 4 kHz. In particular, this ${\Sigma}-{\Delta}$ modulator is well suited for high accuracy measure systems. The whole modulator consumes only 3-mW from a single 3.3V supply in a $0.35-{\mu}m$ CMOS technology.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1189-1194
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• 2000

The purpose of this investigation is to establish which consequence is happen about initial curing concrete's compressive strength of 7days, 28days which changes W/C ratio by the change of vibrating speed and vibrated time. An experimental parameter is fixed 4 degrees of W/C ratio(45%, 50%, 55%, 60%), 3 degrees of vibrated time(3hr, 6hr, 12hr) and different vibrating speed(0.25kine, 0.5kine, 1kine). As the result, compressive strength of 7days was increased when vibrating speed and vibrated time is 1kine, 12h and also compressive strength of 28days was increased when vibrating speed and vibrated time is 0.25kine and 3hr.

• The Korean Journal of Ecology
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• v.23 no.1
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• pp.51-57
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• 2000

Concentrations of cadmium, copper and zinc were determined in three molluscan species including Sacculosiphonaria japonica, Reishia clavigera and Crassostrea gigas to assess heavy metal contamination in the Onsan Bay. The range of cadmium concentrations were 3.83∼39.67 ㎍/g d.w. in S. japonica, 7.47∼103.47 ㎍/g d.w. in R. clavigera, 1.32∼92.17 ㎍/g d.w. in C. gigas. Concentration of cadmium at contaminated site in C. gigas was 70 folds higher than that of reference site. The range of copper concentrations were 22.92∼1287.56 ㎍/g d.w. in S. japonica, 37.53∼656.97 ㎍/g d.w. in R. clavigera, 161.50∼3208.52 ㎍/g d.w. in C. gigas. The concentration of copper at contaminated site in S. japonica was 56 folds higher than that of reference site. The range of zinc concentrations were 93.48∼377.40 ㎍/g d.w. in S. japonica, 423.65∼1075.57 ㎍/g w. in R. clavigera, 2018.13∼22275.00 ㎍/g d.w. in C. gigas. The difference of zinc concentrations between reference site and contaminated site was relatively small than those of cadmium and copper in all the species tested. The largest difference was 11 folds in C. gigas. In the present work, we confirmed that all of these species, S. japonica, R. clavigera and C. gigas, could be used as biological indicators to monitor heavy metal contamination.

• Journal of Korea Foundry Society
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• v.33 no.1
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• pp.1-7
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• 2013

The effect of the Mo addition on the high temperature creep properties of the 9Cr-3W steel was also evaluated. Two experimental steels, (9Cr-3W and 9Cr-3W-0.5Mo), were prepared using a vacuum induction melting process, followed by hot rolling and heat treatment processes. Three types of precipitates, ($M_{23}C_6$, Nb-rich MX and V-rich MX) were observed in a typical tempered martensitic matrix. Significant effects of the Mo addition on the tensile properties were not observed. However, the creep properties at $650^{\circ}C$ under applied stresses of 140 and 150 MPa were considerably enhanced by the Mo addition. The microstructural observation after the creep test indicated that the addition of Mo could function to retain the recovery of the martensitic matrix, thus resulting in the enhanced creep properties of the 9Cr-3W-0.5Mo steel. Furthermore coarsening of the $M_{23}C_6$ carbides and formation of Laves phases were observed in both samples after the creep tests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.947-951
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• 2015

The objective of this study is to numerically investigate the cooling characteristics of the heat sink as a cooling device for the amplifier. In order to analyze the heat transfer performances of the heat sink, the steady-state thermal model of the ANSYS software was used and analyzed with the fin thickness, fin pitch and fin number of the heat sink. As a result, the temperature at the junction of heat sink was decreased with the increase of fin thickness and fin number. In addition, the thermal resistances of the heat sinks were enhanced from $0.764^{\circ}C/W$ to $0.739^{\circ}C/W$ and $1.254^{\circ}C/W$ to $0.610^{\circ}C/W$, respectively, with the increase of the fin thickness from 1 mm to 3 mm and fin number from 9 to 20, respectively.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.8 no.3
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• pp.1-11
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• 2012

Mongolia has three(3) geothermal zones and eight(8) hydrogeothermal systems/regions that are, fold-fault platform/uplift zone, concave-largest subsidence zone, and mixed intermediate-transitional zone. Average temperature, heat flow, and geothermal gradient of hot springs in Arhangai located to fold-fault platform/uplift zone are $55.8^{\circ}C$, 60~110 mW/m2 and $35{\sim}50^{\circ}C/km$ respectively and those of Khentii situated in same zone are $80.5^{\circ}C$, 40~50 mW/m2, and $35{\sim}50^{\circ}C/km$ separately. Temperature of hydrothermal water at depth of 3,000 m is expected to be about $173{\sim}213^{\circ}C$ based on average geothermal gradient of $35{\sim}50^{\circ}C/km$. Among eight systems, Arhangai and Khentii located in A type hydrothermal system, Khovsgol in B type, Mongol Altai plateau in C type, and Over Arhangai in D type are the most feasible areas to develop geothermal power generation by Enhanced Geothermal System (EGS). Potential electric power generation by EGS is estimated about 2,760 kW at Tsenher, 1,752 kW at Tsagaan Sum, 2,928 kW at Khujir, 2,190 kW at Baga Shargaljuut, and 7,125 kW at Shargaljuut.