• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.312-321
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• 2023

Fluidized beds have been widely used in industrial applications, which in most of them, the operating fluid is non-Newtonian. In this study, the combination of the lattice Boltzmann method (LBM) and the smoothed profile method has been developed for non-Newtonian power-law fluids. The validation of the obtained model were investigated by experimental correlations. This model has been used for numerical studying of changing the operating fluid and geometrical parameters on the expansion behavior in liquid-solid beds with both Newtonian and non-Newtonian fluids. Investigations were performed for seven different geometries, one Newtonian, and two non-Newtonian fluids. The power-law index was in the range of 0.8 to 1, and the results for the Newtonian fluidized beds show more porosity than the non-Newtonian ones. Furthermore, increasing the power-law index resulted in enhancing the bed porosity. On the other hand, bed porosity was decreased by increasing the initial bed height and the density of the solid particles. Finally, the porosity ratio in the bed was decreased by increasing the solid particle diameter.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1270-1277
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• 2003

The extrusion conditions of the soymilk residue and corn grits mixtures were optimized. The experiment was designed according to the D-optimal design of response surface methodology (RSM), which shows 18 experimental points including 4 replicates for three independent variables (screw speed, water content and die temperature). The responses variables such as bending force, expansion ratio, bulk density, water solubility index (WSI), water absorption index (WAI), and color values (L＊, a＊, b＊) were evaluated using response surface analysis. Expansion ratio and WSI decreased with increasing water content, whereas bulk density tended to increase with increasing water content. While greater screw speeds enhanced WSI and yellowness, higher moisture contents decreased the expansion ratio and WSI value. However, die temperature did not influence upon the response variables. The optimum extrusion conditions by numerical and graphical methods were similar: the screw speed, water content, and die temperature were 250 rpm, 22.43% and l28.16$^{\circ}C$ by the numerical method; 250 rpm, 22.43%, and 128.02$^{\circ}C$ by graphical method.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.617-622
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• 2003

Experimental designs were applied to optimize the mixture ratio for the extrudate made by soymilk residue and corn grits. Nine candidate points were examined for their significance on extrudate using the modified distance design. Bending force, expansion ratio, bulk density, water solubility index (WSI), water absorption index (WAI) and color $(L^*,\;a^*,\;b^*)$ were the significant factors improving the extruded cereal production, and these values were applied to the mathematical models. Results showed that bending force, expansion ratio WSI, WAI and color $(L^*,\;b^*)$ increased with increasing the corn grits, whereas bulk density tended to decrease. The statistical study showed that the fitted models were adequate to describe the contour plot and all responses. Optimum mixture ratio allowing to maximize the two responses (expansion ratio and $b^*$) and minimize the response (WAI) were examined with a numerical optimization methods. The numerical optimization method was obtained as 53.18% : 46.19% (corn grits : soymilk residue).

• Journal of Chest Surgery
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• v.5 no.1
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• pp.1-8
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• 1972

On the study of surface activity in excized lung extracts of various pulmonary diseases, following facts were concluded. 1]The minimum surface tension measured in lung extracts of tuberculous tissue surrounding cavitary lesion was 26.3dyne/cm and its stability index was 0.53. 2]Macroscopically almost normal lung tissue at a distance of tuberculous lesion in same lobe revealed 21.3 dyne/cm of minimum surface tension in extracts and its stability index showed 0.66. This low surface activity may be due to the chronic pneumonitis microscopically. 3] In the atelectatic lung which had been collapsed by chronic empyema the extracts revealed much higher minimum surface tension in 27.3 dyne/cm and its stabillry index revealed the least value of 0.47 without correlation of duration of disease. This suggests that the longstanding collapsed lung may be soon collapsed even after mechanical full expansion because of lack of surfactant.

• Journal of Embryo Transfer
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• v.9 no.1
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• pp.73-83
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• 1994

The objective of this study was to develop an effective in vitro production system capable of obtaining more porcine embryos from immature oocytes. These experiments were thus conducted to examine the effect of oocytes type and maturation time on the in vitro maturation(IVM) and fertilization(IVF) of oocytes and the in vitro development (IVD)of IVF embryos. 1. The degree of oocyte maturation based on cumulus expansion index(GEI) did not differ for A- and B-typed oocytes but the index of oocyte type C was lower(P<0.05) than that of other oocyte types. 2. When the oocytes of type A and B were matured for 36, 42 and 48hrs, the GEl was not different between the 36- and 42-h maturation but the GEl after 48hrs was greatly lower(P<0.05) than that of other maturation times. 3. The highest cleavage rate(48.6%) of IVF oocytes was obtained from A typed oocytes and 42-h maturation but the developmental potential based on cleavage index was the highest when B-typed oocytes were matured for 42hrs.

• Journal of the Korea Institute of Building Construction
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• v.22 no.3
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• pp.305-316
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• 2022

Domestic construction companies have difficulty in establishing strategies when entering overseas markets because they do not have an overseas construction economic sentiment index to refer to for data on overseas construction prospects. Considering that the fluctuation of overseas construction orders over the past decade has been substantial and large companies and SMEs are actively advancing overseas, this study developed an evaluation model for an overseas construction business sentiment index to grasp the economic experience of overseas construction companies. In 2021 Korean companies earned 30.6 billion in overseas construction contracts, 87% the level of the previous year, despite difficulties such as COVID-19 and low oil prices, thanks to efforts by construction companies to strengthen their strategies for entry, such as regional diversification, and government support for winning orders. Since the overseas construction industry fluctuates greatly due to changes in the international environment, it is necessary to investigate and analyze the economic sentiment index of overseas construction companies. In particular, despite the increase in overseas expansion of small and medium-sized construction companies and engineering companies, the provision of information on the overseas construction market sentiment index is insufficient, limiting the establishment of strategies for overseas construction expansion. Therefore, this study intends to develop an overseas construction market sentiment index model that can understand the economic sentiment of overseas construction companies, provide a forecast for overseas construction, and use it to establish overseas construction strategies and policies.

• Journal of the Korean association of regional geographers
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• v.10 no.2
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• pp.407-427
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• 2004

The rapid innovation of information and communication technology and its sharp falling prices have brought about the expansion of the Internet, integrating the world as one space under converged space and time. This rapid expansion of the Internet and its application in the economy have spurred the emergence of the digital economy. The Internet has influenced strongly on the changes of not only economic activities but also political, social and cultural activities. In this context, a rapidly increasing Internet expansion renders the rhetoric about the death of distance and about the meaningless of geographical place. However, the development and expansion of Internet induces a growing digital divide among nations and also a spatial inequality in a nation as the supply of the Internet has concentrated towards demand-affluent large cities. A large gap of digital access has been occurred between high income and low income countries according to a measurement of the international digital access index. In a national level, the Internet backbone has been built around large cities which favor a large amount of the Internet demand, and the affordable accessibility of these cities for the Internet services has influenced strongly on the agglomeration of Internet related industries, further inducing the construction and investment of the Internet backbone into large cities as cumulative causation effects. As a result, the expansion of the Internet affects immensely on the changes of spatial structure in a nation resulting in the new spatial phenomena such as centralization, concentration and splintering in the digitalized space-economy.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.3
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• pp.249-277
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• 2023

The purpose of this study is to explore the potential contribution of citation metrics to improving the search performance of citation index databases. To this end, the study generated ten queries in the field of library and information science and conducted experiments based on the relevance assessment using 3,467 documents retrieved from the Web of Science and 60,734 documents published in 85 SSCI journals in the field of library and information science from 2000 to 2021. The experiments included re-ranking of the top 100 search results using citation metrics and search methods, query expansion experiments using vector space model retrieval systems, and the construction of a citation-based re-ranking system. The results are as follows: 1) Re-ranking using citation metrics differed from Web of Science's performance, acting as independent metrics. 2) Combining query term frequencies and citation counts positively affected performance. 3) Query expansion generally improved performance compared to the vector space model baseline. 4) User-based query expansion outperformed system-based. 5) Combining citation counts with suitability documents affected ranking within top suitability documents.

• Land and Housing Review
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• v.2 no.3
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• pp.259-268
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• 2011

Space extension and the increase of the number of households are helpful to raise business value of the remodeling through the renovation of apartment houses that is required by residents of new cities and large-scaled apartment. However, in the case of accepting this demand, it could have a bad influence on the landscape of a complex in terms of the structure of apartment houses and the safety of construction and urban planning, and a problem occurs in the aspect of fairness for reconstruction. For the study, the current status related to the remodeling system through laws, related articles since 2000 and research data was analyzed. In addition, the individual quantitative analysis was conducted in the four aspects to judge whether households expansion for remodeling is plausible:1) Statistical data to comprehend the changes of population and social structure 2) Survey data of floor space index and the building-to-land ratio of new cities at the intial stage for the review of the effect of architectural planning and urban environment 3) Surveys of experts on structural safety in order to judge whether the demand of expansion is accepted or not. 4) Quantitative analysis of each item to compare fairness with reconstruction. Therefore, this study is intended to understand problems of the remodeling system that is currently operated. Moreover, it will be further reviewed that the expansion of households is feasible through the permission of expansion and it will be discussed that the revitalization of the apartment remodeling has a positive impact on the residential environment.

• 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.