• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.303-306
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• 2009

High temperature solid oxide fuel cells (SOFCs) offer a clean, pollution-free technology to electrochemically generate electricity at high efficiencies. Solid oxide fuel cells in several different designs have been investigated; these include planar and tubular geometries. The tubular type cell is widely researched due to it have advantages about thermal expansion and sealing issues. Unfortunately, lab scale tubular cell for testing has thermal expansion and sealing problems. The previous Jig for lab scale tubular cell testing has many sealing problems. When we feed fuel gas to jig inlet, ceramic glue sealant has amount of gas expansion pressure, because temperature of feeding gas changes ambient temperature to high temperature ($700{\sim}900^{\circ}C$). Furthermore, when we carry out long time test, something like degradation test, crack of ceramic glue sealant due to weakness of mechanical properties can make stop working the test. Additionally, we reduce setting process for assembling, because micanite is not required drying or debinding process.

• International Journal of Highway Engineering
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• v.14 no.6
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• pp.37-43
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• 2012

PURPOSES : This study is to evaluate the feasibility of setting the standard of cement alkali content by using ASTM C 1260(accelerated mortar bar test) METHODS : This study analyzes the ASR(alkali silica reaction) expansion of cement mortar bar based on the changes in the aggregate type(fine, coarse), cement type(ordinary, low alkali), and replacement contents of fly ash. ASR tests were conducted according to ASTM C 1260. RESULTS : In this test results, There is no big difference in the ASR expansion between ordinary cement and low alkali cement. From this test results, it was found that the variation of cement alkali content did not have a effect on ASR expansion because mortar bar was placed in a container with sufficient alkali aqueous solution at high temperature during the test process of ASTM C 1260. CONCLUSIONS : It is evidently clear that the alkali content of cement have a effect on ASR. But ASTM C 1260 is difficult to assess this effect.

• 한국전산유체공학회:학술대회논문집
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• 2000.05a
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• pp.45-50
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• 2000

We study a conceptual numerical model on shock-vortex interaction setting an impulsive shock in a compressible vertex. Navier-Stokes equations are solved for the investigation of interactive structure and acoustic wave propagation. The rotationally symmetric vortex enforces two compression-expansion pairs resultantly forming a quadrupolar shape. These compressive and expansive waves cylindrically propagate to the far field and turn to acoustic waves. Using a fine uniform Cartesian grid system and a TVD-high resolution method, the flow data irl: precisely obtained to extend our interest to the sound source.

• 한국항공운항학회:학술대회논문집
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• 2016.05a
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• pp.178-191
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• 2016

Incheon International Airport (IIA) is trying to boost itself up for the Hub airport with a proactive marketing and large scale of airport expansion plan. Even the transfer rate of IIA for now is not high enough for a Hub airport, it is expected to keep increase for the future due to an effort to be the Hub. This study is to be made for setting the standards of airport planning as to the transfer rate based on the research of operational characteristics of Hub airport.

• Journal of the Korean Ceramic Society
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• v.31 no.4
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• pp.420-426
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• 1994

A new method is proposed for the oxide lattice energy calculation. It is consisted of (1) setting a central and a computation domains in a real lattice, (2) calculation of inter-ionic potential producted by the associated portion of each ion to the relative domain, and (3) summing up the potential energies. Even with a slight expansion of the domain, the lattice energy converges to the published data. The method is superior than any other reported due to the simple and clear concept and the reduced computing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.151-160
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• 2020

Various smart city projects have been actively promoted as important policies of governments in various countries. The key to the success of smart cities led by governments is to develop sustainable governance through the expansion and proliferation of outcomes. This study comparatively analyzed the smart city policies of the USA and Europe from viewpoints of outcome expansion and proposed policy directions for smart cities in Korea. The comparison items were case cities, the expansion of smart city technologies and services, the measurement of outcomes, the accumulation of knowledge and information, and standardization. This study found that the items of each index were linked for the purpose of assessment, expansion, and the creation of successful cases in the USA and Europe. Based on our analysis, four policy directions were proposed that included the early provision of follow-up measures for case cities, the development of a project performance assessment system, the provision of an integrated knowledge accumulation system, and an earnest promotion of industry activation policies.

• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.205-212
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• 2004

Recently, as concerns over environmental issues are raised more and more trend to use recycled waste for producing construction materials is also raised. Especially, a case of waste resin is considerably destroying the environment due to disposal way that most waste resin produced is disposed of landfill. This study is performed by polymer concrete with recycled PET resin in terms of obtaining safely clean construction resources and protection of environment. High setting shrinkage and sensitivity to heat are main disadvantages of Polymer Concrete (PC) despites of a lot merits. The aim of this study is to investigate basic properties such as setting shrinkage, length change and sensitivity to heat about PET recycled polymer concrete. The other is to check the possibility of use of Montmorillonite as one of a lot of additive without special coupling agent. As results of experiments, various properties of polymer concrete with recycled PET resin are similar with conventional PC except that polymerization time is longer. Montmorillonite was efficiently used to reduce setting shrinkage, length change and coenicient of thermal expansion related to heat with enhanced strength

• Journal of Chest Surgery
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• v.47 no.1
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• pp.6-12
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• 2014

Background: Although a residual intimal tear may contribute to the dilatation of the descending aorta following surgical repair of acute type I aortic dissection (AD), its causal relationship has not been elucidated by clinical data due to the limited resolution of imaging modalities. Methods: This study enrolled 41 patients (age, $55.2{\pm}11.9$ years) who were evaluated with dual-source computed tomography (CT) imaging of the whole aorta in the setting of the surgical repair of acute type I AD. Logistic regression models were used to determine the predictors of a composite of the aortic aneurysm formation (diameter >55 mm) and rapid aortic expansion (>5 mm/yr). Results: On initial CT, a distal re-entry tear was identified in 9 patients. Two patients failed to achieve proximal tear exclusion by the surgery. Serial follow-up CT evaluations (median, 24.6 months; range, 6.0 to 67.2 months) revealed that 14 patients showed rapid expansion of the descending aorta or aortic aneurysm formation. A multivariate analysis revealed that the residual intimal tear (odds ratio [OR], 4.31; 95% confidence interval [CI], 1.02 to 19.31) and the patent false lumen in the early postoperative setting (OR, 4.64; 95% CI, 0.99 to 43.61) were predictive of the composite endpoint. Conclusion: The presence of a residual intimal tear following surgery for acute type I AD adversely influenced the expansion of the descending aorta.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.3
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• pp.20-33
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• 2006

Because of rapid expansion of third party logistics, fierce competition in the transportation industry, and the diversification and globalization of transportation channels, an effective transportation planning by means of multimodal transport is badly needed. Accordingly, this study aims to suggest an optimal transport algorithm for the multimodal transport in the international logistics. As a solution for this problem, first of all, we have applied a pruning algorithm to simplify it, suggesting a heuristic algorithm for constrained shortest path problem to find out a feasible area with an effective time range, which has been applied to the Label Setting Algorithm, consequently leading to multiple Pareto optimal solutions. Also, in order to test the efficiency of the algorithm for constrained shortest path problem, this paper has applied it to the actual transportation path from Busan port of Korea to Rotterdam port of Netherlands.

• Journal of the Korea Society of Computer and Information
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• v.26 no.11
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• pp.67-74
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• 2021

This paper intends to analyze the role expansion of characters, which was an important factor in setting the worldview in storytelling. With the development of media, the way of setting the worldview began to change. At the center of these changes are 'Transmedia' and 'Metaverse', which have recently been receiving attention. With the development of trans media, where the intersection and convergence of media is actively attempted, characters are breaking free from their innate limitations, crossing various media, and performing various activities in new stories. In addition, in the metaverse, an extended concept of the real world, avatars play a role in constructing and expanding the metaverse world as users and creators. By analyzing these changes, we would like to deal with the phenomenon in which character setting, which was used as an element in orthodox world view setting, replaces the world view.