• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.4
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• pp.175-180
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• 2011

The doping effect of Cu in the Sr-doped lanthan manganites (LSM) has been investigated in terms of structural analysis and thermal expansion coefficient (TEC). The $La_{0.8}Sr_{0.2}Mn_{1-x}Cu_xO_3$ ($0{\leq}x{\leq}0.3$) were prepared by solid state reaction method and their crystal structure and TEC were measured. A decrease in the lattice parameters and the TEC were observed with increase eu content, whereas they were decreased for x = 0.3. For $0{\leq}x{\leq}0.2$, the decrease of the lattice parameter and the TEC with increase Cu content were attributed to the reduction of ionic radius of Cu ions due to the presence of $Cu^{3+}$ ions. For x = 0.3, however, the increase was originated from the formation of oxygen vacancies due 10 the presence of $Cu^{2+}$ and $Mn^{4+}$.

• Journal of the Korean Magnetics Society
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• v.14 no.1
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• pp.7-12
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• 2004

The annealing-temperature dependence of magnetic properties in compressed powder cores being composed of ball-milled F $e_{73.5}$C $u_1$N $b_3$S $i_{15.5}$ $B_{7}$ alloy powders (size 250∼850${\mu}{\textrm}{m}$) and 5 wt% of ceramic insulators has been investigated. When annealed at 5$50^{\circ}C$ for 1 h and so transformed to $\alpha$-Fe phase nanocrystalline structure with the grain size of 11 nm (electrical resistivity : 110 $\mu$Ω$.$cm), the highest effective permeability of 125 and quality factor of 53 were obtained, and the permeability persisted up to about 500 KHz. Further the core loss measured at the frequency of 50 KHz and the induction amplitude of 0.1 T was very low (230 mW/㎤). However the dc bias characteristics was not satisfactory as compared to that of conventional powder core materials(MPP, Sendust etc.). The inferior dc bias property of F $e_{73.5}$C $u_1$N $b_3$S $i_{15.5}$ $B_{7}$ alloy powder cores was attributed to the fact that the size of powder was too large for obtaining the same permeability with that of conventional materials.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.4
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• pp.69-74
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• 2010

A new package substrate for dynamic random access memory(DRAM) devices has been developed using selective aluminum anodization. Unlike the conventional substrate structure commonly made by laminating epoxy-based core and copper clad, this substrate consists of bottom aluminum, middle anodic aluminum oxide and top copper. Anodization process on the aluminum substrate provides thick aluminum oxide used as a dielectric layer in the package substrate. Placing copper traces on the anodic aluminum oxide layer, the resulting two-layer metal structure is completed in the package substrate. Selective anodization process makes it possible to construct a fully filled via structure. Also, putting vias directly in the bonding pads and the ball pads in the substrate design, via in pad structure is applied in this work. These arrangement of via in pad and two-layer metal structure make routing easier and thus provide more design flexibility. In a substrate design, all signal lines are routed based on the transmission line scheme of finite-width coplanar waveguide or microstrip with a characteristic impedance of about $50{\Omega}$ for better signal transmission. The property and performance of anodic alumina based package substrate such as layer structure, design method, fabrication process and measurement characteristics are investigated in detail.

• Journal of the Korean Electrochemical Society
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• v.12 no.2
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• pp.189-195
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• 2009

$\beta-Ga_{2}O_{3}$ nanorods were synthesized by chemical vapor deposition method using nickel-oxide nanoparticle as a catalyst and gallium metal powder as a source material. The average diameter of nanorods was around 160 nm and the average length was $4{\mu}m$. Also, we confirmed that the synthesis of nanorods follows the vapor-solid growth mechanism. From the results of X-ray diffraction and HR-TEM observation, it can be found that the synthesized nanorods consisted of a typical core-shell structure with single-crystalline $\beta-Ga_{2}O_{3}$ core with a monoclinic crystal structure and an outer amorphous gallium oxide layer. Li/$\beta-Ga_{2}O_{3}$ nanorods cell delivered capacity of 867 mAh/g-$\beta-Ga_{2}O_{3}$ at first discharge. Although the Li/$\beta-Ga_{2}O_{3}$ nanorods cell showed low coulombic efficiency at first cycle, the cell exhibited stable cycle life property after fifth cycle.

• Asia pacific journal of information systems
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• v.21 no.2
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• pp.59-87
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• 2011

These days, firms are focusing on the improvement of relationships with business partners. The supply chain integrations are taking critical role in improving the relationships with business partners. In accordance with the development of the IT technology, it became possible for firms not only to integrate inner parts of the organization, but also to integrate the company with other organizations in the supply chain. Therefore, in e-Biz environments, it is imperative for firms to strengthen the core capacity through the supply chain, and to precisely determine the components of the determinants of e-Business integration which impact the firm performance. This study analyzed determinants that have impacts on e-business integration in e-business capacity perspectives in competitive environments. This study based on the premise that the resources and capacities that Grant(1991) and Hart(1995) emphasized do not directly influence the corporate performance. This study focused on the fact that corporate must create core competencies based on these capacities to establish competitive edge. Therefore, this study model analyzed to find out which e-Biz competencies are needed to integrate e-Biz according to competitive environment elements. This study designed to empirically analyze the impact of the e-Biz competencies to the e-Biz integration and to the corporate performance. Independent variables of this study-IT management, partner management, e-Biz knowledge, e-Biz establishment and proliferation, process innovation-are selected based on precedent studies on e-Biz competencies. We selected intermediate variables to verify that e-Biz competencies do not have direct impact on the corporate performance, but have impact on the e-Biz integration, which is intermediate effect. That is to verify that if the components of supply chain improve the integration level using e-Biz competencies, the overall supply chain performances will improve. Dependent variables are selected to verify that e-Biz integration has impacts on corporate performances. This study used factor analysis, path analysis, moderating effect analysis as statistical tests. First, we used exploratory factor analysis and confirmatory factor analysis to analyze reliability and validity. Because e-Biz competencies are presented variously by preceding studies, we used SPSS16.0 to verify if survey questionnaire used by theoretical backgrounds is properly composed. Second, we tested the property of structure model by AMOS. We did path analysis using AMOS16.0 to test structure that is composed of e-Biz competencies and e-Biz integration. Last, we tested moderating effects of measure factors. We analyzed 163 domestic companies to find out many significant suggestive points. First, relationship improvement capacity, e-business knowledge sharing capacity with business partners, and process innovation capacity are adopted as determinants of differentiation and competitive edges against competing firms. Second, e-business knowledge sharing capacity, and process innovation capacity are analyzed as the determinants of e-business integration in the firm which demand fluctuation in the market is high. On the other hand, among the determinants that require capturing ideas on new products, and strengthening the technological power, process innovation capacity are adopted as the determinants. These results provide us the foundation that the determinants that we have analyzed can impact the supply chain integration strategies which take into account the competitive environments.

• Fire Science and Engineering
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• v.31 no.2
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• pp.1-8
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• 2017

A sandwich panel is a composite material composed of a double-sided noncombustible material and insulation core which is used in the inner, outer walls, and roof structure of a building. Despite its excellent insulation performance, light weight and excellent constructability, a flame is brought into the inside of the panel through the joint between the panels, melting the core easily and causing casualties and property damage due to the rapid spread of flame. The current Building Law provides that the combustion performance of finishing materials for buildings should be determined using a fire test on a small amount of specimen and only a product that passes the stipulated performance standard should be used. This law also provides that in the case of finishing materials used for the outer walls of buildings, only materials that secured noncombustible or quasi-noncombustible performance should be used or flame spread prevention (FSP) should be installed. The purpose of this study was to confirm the difference between the dangers of horizontal and vertical fire spread by applying FSP, which is applied to finishing materials used for the outer walls of buildings limitedly to a sandwich panel building. Therefore, the combustion behavior and effects on the sandwich panel according to the application of FSP were measured through the construction to block the spread of flame between the panels using a full scale fire according to the test method specified in ISO 13784-1 and a metallic structure. The construction of FSP on the joint between the panels delayed the spread of flame inside the panels and the flash over time was also delayed, indicating that it could become an important factor for securing the fire safety of a building constructed using complex materials.

• Journal of Korean Society of Disaster and Security
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• v.10 no.1
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• pp.85-90
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• 2017

The purpose of this study is to investigate the effect of vertical and horizontal refraction on the lower part of the power supply and control system of various facilities and machinery that use electricity, so that the power distribution system, which is an important electric facility installed in buildings and public facilities, Type earthquake resistant pads to protect the substructure and prevent short-circuiting on the upper part of the system. The GR-63-CORE (Scale 8.3 class) It is earthquake disaster prevention and disaster prevention technology that satisfies seismic performance. As a research result, it is possible to protect the electricity and communication infrastructure, which can contribute to shortening the time for recovering the electric facilities to the normal state in case of an earthquake, and preventing the fire caused by the destruction of the electricity supply facility in case of an earthquake. As a result, it is possible to minimize the spread of fire that occurs when a large-scale earthquake occurs and to minimize the damage of people and damage to property, and it can contribute to the securing of electric infrastructure that enables citizens to quickly recover to daily life even after suffering a major earthquake. In addition, the technology can be applied to ensure the seismic resistance of the equipment in the communication and computer room, and it can be applied to various fields where the facility function can be stopped due to the shaking of the earthquake base.

• Journal of The Korean Association of Information Education
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• v.8 no.3
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• pp.353-360
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• 2004

World Wide Web is not more meaningless sea of information but is becoming the Semantic Web that provides many users with meaningful information. The starting point is the XML and metadata, RDF is a stopover which gives technique to relate arbitrary web resources. And now, the semantic and logic of web resources can be settled in the Ontology. A lot of educational multimedia web resources in Korea have produced their metadata with KERIS's KEM(Korea Educational Metadata). Therefore our country have to start the study of the semantic and logic in web resources. But, many researchers in Korea are more eager to study Dublin Core's DC and SCORM's LOM metadata specification than KEM. Thus the study of method about sharing and integrating these three metadata specifications should be performed before the study of semantic and logic in web resources in Korea. We design the Ontology to integrate these three metadata specifications and implement the prototype system using this Ontology. These three metadata have some elements that have same labels and meanings, and other elements have different labels and same meanings. To match these different labels which have same meanings, we adapted the one-to-one mapping technique in designing our Ontology. This designed Ontology was imported as "integrated schema" in our prototype searching system to integrate three different metadata in databases. Moreover we know that the more specific property design of class in Ontology was needed in order to provide users with more informed searching results such as synonym, antonym, hierarchy and associations.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.613-622
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• 2012

A chrome absorbent that is useful in rapid magnetic recovery and recycling was developed though a synthesis of Multi-Terminalized Magnetic-core Dendrimer (MTMD). Divergence through coprecipitation and rotation growth was used for synthesis. The dendrimer was multi-terminilized through methyl propionate and glutaric acid. The property analysis of the synthesized sample was performed through XRD, FT-IR, TEM, EDS, TGA and zeta potential analyzer. A magnetic-core of MTMD had a magnetite crystal and the size of 4th generation dendrimer was identified to be from 15 nm to 20 nm. Through the analysis of the TGA, the rate of the dendrimer branch for the first generation dendrimer was about 7% and 3% of diminished weight occurred as the generation grows. Also, the potential of the dendrimer when multi-terminalized, had variation from 25.26 mV to -6.53 mV. As a result of MTMD adsorption experiment, it absorbed more than 80% within 5 minutes and indicated absorptivity of 6.308 mg/g. When it was compared with COOH Dendrimer (COOH-D) after magnetic recovery, the recovery time was rapidly reduced by more than half and it could recover 100% within 30 minutes. In case of the regeneration experiment that used chrome, it was identified to maintain the same adsorptivity for four runs.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.2
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• pp.27-43
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• 2024

Recently, the importance of trademarks as a core resource of corporate competitiveness to protect and differentiate products and services is increasing. Global companies are focusing hard to secure trademark rights to manage brands that reflect their core values and to respond to increasingly frequent trademark disputes, while start-ups and individuals are working hard to secure trademark to run stable businesses and attract investment funds. Meanwhile, this study conducts an empirical analysis to identify the relationship between the brand and business strategy of domestic venture startups. The analysis data used was the response data of 2,230 corporate companies from the 2021 Venture Business Precision Survey, and the propensity score matching method, structural equation model analysis, and binomial logit analysis were used as analysis methods. As a result of the analysis, it was confirmed that domestic venture startups' trademark ownership does not make a significant difference in terms of the level of business strategy. This was confirmed to be because the brands of domestic venture start-ups mainly advance their business strategies only through the internal competency process, while the advancement of business strategies through the external competency process is very minimal. Meanwhile, it was confirmed that the level of cost advantage strategy among the business strategy levels of venture start-ups strengthens the tendency to hold trademarks, indicating that the higher the completeness of the cost advantage level, the more likely it is to expand trademark ownership for stable sales and supply of products and services through trademark ownership and to convert to high value-added in the future.