• Journal of Powder Materials
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• v.9 no.5
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• pp.352-358
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• 2002

The effects of boron or manganese added as $B_4C$, Mn, $TiB_2$, B on TiC-30vo1.%$Ni_3Al$ cermet sintered at 1380 and $1400^{\circ}C$ for 1 hour, were examined in relation with shrinkage, relative density, microstructure, lattice parameter, hardness and fracture toughness ($K_{IC}$). The results are summarized as follows: 1) The highest shrink-age showed about 30.5% in the specimen added B$_4$C and the maximum relative density was about 99% in the specimen added $TiB_2$; 2) The grains of TiC were grown during sintering and made the surrounding structure by adding boron and manganese. The largest grain size showed about $2.8\mutextrm{m}$ in the specimen with boron sintered at $1400^{\circ}C$;3) The lattice parameter of TiC was about $4.325\AA$ and $Ni_3Al$ about $3.592\AA$ by adding other elements; 4) The highest hardness was about $1100kgf/\textrm{mm}^2$ in the specimen with B4C; 5) The fracture toughness ($K_{IC}$) showed about $15MNm^{-3/2}$ in the specimen added $TiB_2$.

• Progress in Superconductivity
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• v.10 no.1
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• pp.40-44
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• 2008

A combined process of a mechanical ball milling and liquid glycerin ($C_{3}H_{8}O_3$) treatment of boron (B) powder has been conducted to enhance the superconducting properties of $MgB_2$. The individual aims of the mechanical milling and the glycerin treatment were to reduce the grain size of the $MgB_2$ and to achieve homogeneous carbon (C) incorporation into the $MgB_2$, respectively. Four kinds of B powders of as-received, glycerin treated, 2 h milled, and 2 h milled + glycerin treated were prepared. $MgB_2$ bulks were fabricated by in situ process using the prepared B powders. The mechanical ball milling was effective for a grain refinement, and a lattice disorder was easily achieved by glycerin addition. It was found that the critical current density ($J_c$) values were enhanced in the samples with milled B or glycerin treated B only. In the $MgB_2$ bulk prepared with both milled and glycerin treated B, the $J_c$ was further increased due to a higher grain boundary density and a greater C substitution.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.2
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• pp.145-151
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• 2000

The sintering behaviour of monolithic zirconium diboride (ZrB$_{2 }$) and ZrB$_{2 }$-based composite ZrB$_{2 }$-ZrC were studied using a pressureless sintering technique. The specimens were prepared using commercially available ZrB$_{2 }$ and ZrC powder which were pressed and subjected to pressureless sintering. The effects of lanthanum and neodymium used as sintering aids in the sintering processes were investigated. The sintered specimens were characterized using X-ray diffraction analysis and scanning electron microscopy. The ZrB$_{2 }$ specimen prepared using and addition of 1 wt% lanthanum and pressurelessly sintered at $2200^{\circ}C$ showed the maximum relative density of 96%. The ZrB$_{2 }$-ZrC composite specimen without the addition of any sintering aids exhibits the maximum sintered density but contains significantly detectable amount of secondary phase.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.135-140
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• 1997

The influences of ZrB$_2$ additions to SiC on microstructural, DDM(Electrical Discharge Machining), mechanical and electrical properties were investigated. composites were prepared by adding 15, 30, 45 vol.% ZrB$_2$particles as a second phase to SiC matrix. SiC-ZrB$_2$ composites obtained by hot pressing for high temperature structural application were fully dense with the relative densities over 99%. The fracture toughness of the composites were increased with the ZrB$_2$contents. In case of composite containing 30vol.% ZrB$_2$, the flexural strength and fracture toughness showed 45% and 60% increase, respectively compared to that of monolithic SiC sample. The electrical resistivities of SiC-ZrB$_2$ composites decreased significantly with the ZrB$_2$ contents. The electrical resistivity of SiC-30vol.% ZrB$_2$ composite showed 6.50$\times$10$^{-4}$ $\Omega$.cm. Cutting velocity of EDM of SiC-ZrB$_2$ composites are directly proportional to duty factor of pulse width. Surface roughness, however, are not all proportional to pulse width. Higher-flexural strength composites show a trend toward smaller crater volumes, leaving a smoother surface; the average surface roughness of the SiC-ZrB$_2$ 15 vol.% composite with the flexural strengthe of 375㎫ was 3.2${\mu}{\textrm}{m}$, whereas the SiC-ZrB$_2$ 30.vol% composite of 457㎫ was 1.35${\mu}{\textrm}{m}$. In the SEM micrographs of the fracture surface of SiC-ZrB$_2$ composites, the SiC-ZrB$_2$ two phases are distinct; the white phase is the ZrB$_2$and the gray phase is the SiC matrix. In the SEM micrographs of the EDM surface, however, these phases are no longer distinct because of thicker recast layer of resolidified-melt-formation droplets present. It is shown that SiC-ZrB$_2$ composites are able to be machined without surface cracking.

• Journal of Korea Foresty Energy
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• v.19 no.1
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• pp.1-6
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• 2000

This study was carried out to investigate the growth responses of Pinus densiflora seedlings to enhanced UV-B environment for 16 weeks in the field condition. The seedlings were treated with one of three levels of UV-B dosages - ambient UV-B, ambient + 3.2, and ambient + 5.2 KJ m$^{-2}$day$^{-1}$ and the irradiation was performed at the stage before the germination, the fully expanded cotyledon, and the primary needles grown more than 0.8cm in length of the seedlings, respectively. Enhanced UV-B irradiation reduced the height and the root collar diameter growth, and dry mass production of the seedling, and T/R ratio was increased by the UV-B treatment. Difference in seedling growth was observed by difference in time of the UV-B treatment. Among the seedlings which were treated with ambient - 3.2 KJ m$^{-2}$day$^{-1}$, height and root collar diameter growth was relatively high in the seedling received the UV-B treatment at the stage before the germination. The lowest dry mass production was observed in the seedlings received the UV-B at stage of cotyledon both in two levels of enhanced UV-B treatment. Chlorophyll concentration was reduced by enhanced UV-B irradiation, and chlorophyll a/b ratio was increased by the UV-B treatment.

• Journal of Intelligence and Information Systems
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• v.9 no.1
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• pp.211-225
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• 2003

This paper aims at the design of collaborative architecture for business to business (B2B) applications based on Web service protocol. As different business processes should be interfaced in the B2B environment collaboration is important fur the success of B2B implementation. For the development tools, XML, Web services and ASP.NET were adopted Web services are emerging to provide a systematic and extensible framework for application-to-application interaction. The Web services framework is divided into three areas; communication protocols, service descriptions and Web discovery. Web services such as SOAP, WSDL and UDDI correspond to the three areas respectively. ASP.NET is utilized which corresponds to the component and service set located in the top layer of .NET. For the service of product category and product details, Web service architecture was implemented based upon the SQL server database.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.273-282
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• 2005

The purpose of this study is how to apply to e-Commerce of parts procurement system in the Japanese Automobile Industry and examine the influence of that through the case studies of automobile makers. In the Japanese automobile industry, B2B e-Commerce of parts procurement system have a shifted from closed circuits through VAN to opened IP-VPN and eventually to the JNX of internet environment. The Japanese automobile industry depends mainly on IP-VPN and JNX, especially EDI on a one to one basis with parts procurement suppliers. As to the future direction of B2B e-Commerce of parts procurement in the Japanese automobile industry, many of commodity parts will be traded among established participants on internet websites owned by automobile maker groups. Finally, for improvement of B2B e-Commerce of parts procurement in the Japanese automobile industry I suggested that there are 'revitalize of e-Marketplace', 'improvement of IT and business process', 'extension of B2B e-Commerce among small and medium sized suppliers'.

• The Journal of the Korea institute of electronic communication sciences
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• v.3 no.2
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• pp.106-111
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• 2008

At the ubiquitous computing, Mobile RFID, which the convergence RFID and mobile device, researches are core method and infra to service B2B, B2C, and B2B2C service domain. We propose the functions of middleware to develop the mobile RFID device. It consists of multi-code integrated recognition module, the reader control module, the module code interpretation, and Dispatcher module. These functions can recognize the tag of EPC/ISO and mCode type. We describe the zone file of local ODS and the implemented module to read the 13.56MHz tag.

• Proceedings of the CALSEC Conference
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• 2001.08a
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• pp.305-312
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• 2001

1999/10∼2000/09 : INGECEP(Integrated next generation electronic commerce environment Project) 2000. 10 : 제22차 APEC TEL 회의 -〉 INGECEP 종료 보고 -〉 B2B 부문으로의 협력 확대 및 MP간 연동의 필요성을 제기함 200.12 : 국제 B2B 상호호환성 연구 국내 W/G 결성 2001.1 : 국제B2B 상호호환성 연구 국제 W/G 결성 2001 1∼ : "Agent 기반의 국제간 B2B 상호 운용 모델 개발"사업(정보통신부 국가 과제)수행 중

• Journal of Information Technology Applications and Management
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• v.9 no.4
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• pp.179-204
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• 2002

The purpose of this study is to empirically Investigate the critical success factors affecting the participation of B2B e-marketplace from a perspective of buyers and sellers. The research model presented in this study suggests that the success of B2B e-marketplace depends on the degree of participation of buyers and sellers. It is hypothesized that the participation of buyers and sellers is related with several contextual factors. The contextual factors included: (a) industry and market factor; (b) Internal environment factor; (c) product factor; (d) Inter-organizational factor; and (e) B2B e-marketplace system and strategy factor. An analysis of data from 31 buyer firms and 31 seller firms reveals that those five factors have a significant effect on the participation and success of B2B e-marketplace. The implications of the study are discussed and further research directions are proposed.