• Journal of the Korean Chemical Society
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• v.67 no.6
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• pp.420-428
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• 2023

Crosslinking was introduced into vinylized-mesoporous silica and recycled polyethylene. By introducing a vinyl group into the mesoporous silica, it becomes a material capable of inducing cross-linking with non-polar polyethylene. By synthesizing vinylized-mesoporous silica and inducing crosslinking with recycled polyethylene, a recycled polyethylene composite with improved physical properties than existing recycled polyethylene was synthesized. In addition, even when a small amount is added according to the grade of recycled polyethylene using vinylized-mesoporous silica, the crosslinking reaction proceeds and all physical properties are improved. Four types of vinylized-mesoporous silica were synthesized, and the shape, microstructure, and functional groups were analyzed by TEM, BET, FT-IR, and XRD. Using vinylized-mesoporous silica, three types of compounds were blended by crosslinking reaction with recycled polyethylene. In order to confirm the presence or absence of crosslinking, analysis was performed using XPS and FT-IR, and physical properties such as tensile strength, elongation, flexural strength, and flexural modulus were confirmed using a universal testing machine. As a result, by applying vinylized-mesoporous silica to recycled polyethylene in various grades, the weak physical properties of existing recycled polyethylene were overcome. By applying the vinylized-mesoporous silica, recycled polyethylene composite material that overcomes the weak physical properties to the normal polyethylene, it shows the optimal physical property index that can be used commercially. Therefore, it is expected that it can potentially increase the use of recycled polyethylene and recycle resources.

• Food Science and Preservation
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• v.31 no.2
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• pp.276-286
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• 2024

In the present study, we investigated whether a mixture of fucoidan and Crepidiastrum denticulatum extract (FCE) had the potential to improve the therapeutic efficacy of cancer treatment. The results demonstrated that FCE significantly reduced cell viability and induced the release of LDH (lactate dehydrogenase) and DNA fragmentation in HepG2 cells in a dose-dependent manner. In addition, FCE treatment also increased the protein expression level of p53, the release of cytochrome c, and the loss of mitochondrial membrane potential. Moreover, FCE dose-dependently increased protein expression levels of Bax, and cleaved caspase-3 and -9. However, FCE decreased the protein expression level of Bcl-2. These results suggest that FCE inhibits cell proliferation and induces apoptosis via the mitochondrial-mediated intrinsic pathway. The present study demonstrates that FCE can be used as an anti-cancer agent for liver cancer based on apoptosis mechanism.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.4
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• pp.161-182
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• 2024

The study analyzed the rapidly growing food tech startup in South Korea, focusing on industry classification, core technological domains, investment stages, and growth trajectories. Utilizing the ERIS model, two innovative food tech startups, MyChef and CatchTable, were examined as case studies. Results revealed food tech startups are focusing on information technology and smart distribution technology-oriented solutions rather than traditional food production. This study also found that robotics and AI integration were key technology areas. Analyzing the emergence of food tech startups, investment stages, and cumulative investment amounts based on founding years revealed a trend of scaling operations through rounds of funding, especially after securing SERIES A and B funding. The period between 2014 and 2018 saw a dense concentration of food tech startup establishments, likely influenced by favorable conditions for technological innovation amid the Fourth Industrial Revolution. The high rate of strategic mergers and acquisitions and bankruptcy can be interpreted as the complexity inherent in the food tech industry. The case study of MyChef, which grew into HMR manufacturing, and Wad(CatchTable), which expanded into a restaurant reservation platform, derived the entrepreneurs, resources, industry, and strategic factors that served as success factors for food tech startups. This study has practical implications in that it provides entrepreneurs, investors, and policymakers in the food tech industry with insight and direction to develop strategies in line with market trends and technological changes and promote sustainable growth.

• Economic and Environmental Geology
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• v.52 no.6
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• pp.627-635
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• 2019

Cement-asbestos slate is the main asbestos containing material. It is a product made by combining 10~20% of asbestos and cement components. Man- and weathering-induced degradation of the cement-asbestos slates makes them a source of dispersion of asbestos fibres and represents a priority cause of concern. When the asbestos enters the human body, it causes cellular damage or deformation, and is not discharged well in vitro, and has been proven to cause diseases such as lung cancer, asbestos, malignant mesothelioma and pleural thickening. The International Agency for Research on Cancer (IARC) has designated asbestos as a group 1 carcinogen. Currently, most of these slats are disposed in a designated landfill, but the landfill capacity is approaching its limit, and there is a potential risk of exposure to the external environment even if it is land-filled. Therefore, this study aimed to exam the possibility of detoxification of asbestos-containing slate by using exothermic reaction and heat treatment. Cement-asbestos slate from the asbestos removal site was used for this experiment. Exothermic catalysts such as calcium chloride(CaCl₂), magnesium chloride(MgCl₂), sodium hydroxide(NaOH), sodium silicate(Na₂SiO₃), kaolin[Al₂Si₂O₅(OH)₄)], and talc[Mg₃Si₄O₁₀(OH)₂] were used. Six catalysts were applied to the cement-asbestos slate, respectively and then analyzed using TG-DTA. Based on the TG-DTA results, the heat treatment temperature for cement-asbestos slate transformation was determined at 750℃. XRD, SEM-EDS and TEM-EDS analyses were performed on the samples after the six catalysts applied to the slate and heat-treated at 750℃ for 2 hours. It was confirmed that chrysotile[Mg₃Si₂O₅(OH₅)] in the cement-asbestos slate was transformed into forsterite (Mg₂SiO₄) by catalysts and heat treatment. In addition, the change in the shape of minerals was observed by applying a physical force to the slate and the heat treated slate after coating catalysts. As a result, the chrysotile in the cement-asbestos slate maintained fibrous form, but the cement-asbestos slate after heat treatment of applying catalyst was broken into non-fibrous form. Therefore, this study shows the possibility to safely verify the complete transformation of asbestos minerals in this catalyst- and temperature-induced process.

• Journal of the Korean Geographical Society
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• v.30 no.4
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• pp.364-388
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• 1995

Even though rarely recognized as a separate approach, the institutional approach in geography is defined as an attempt to seek an explanation of the phenomena of geographical interest through focusing on the effects of institutional structure and actions. It can provide interdisciplinary links with other works and can offer complementary explanations for geographical interests. The concerns for institutions in geography can be found in early studies, the study of the state, the managerial approach, and the regulation approach. The Korean financial systems can provide good examples to apply institutional concepts into creating spatial outcomes, as it has been regarded as a useful tool to promote Korean economic development. Behind the current spatial pattern of financial systems, four different stages of institutional changes are identified in Korea. Each stage has different institutional features reflecting unique spatial implication.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.557-564
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• 2006

This research was planned and executed to evaluate how the composition of Yak-sun (oriental diet therapy) can effect health conditions of people who are suffering from diet-related diseases like obesity and hyper lipidemia by taking Yak-sun in a form of nutritional supplement with our daily meals. We produced Yak-sun tea with $Ky\hat{a}lmy\hat{a}ngja$, Kamguk, $K\hat{u}m\hat{u}nhwa$, Ch'onkung and observed nutritional composition and evaluated how this tea effects on serum lipids and homocystein concentration by clinical practices. With this observation, we found out that this tea has significant effect on increasing of HDL-cholesterol, decreasing of LDL-cholesterol and homocysteine concentration, and we think that scientific and objective evaluation was done on the components of Yak-sun tea prescription. We concluded that we could apply the components not only in a form of tea, but also in other forms of various food. The information we received from this conclusion will be a basic information on how we can apply oriental medicinal resources into other food and will also be a stepping stone for medicinal herbs to step foot in the field of functional food research, which already draws sizable attention world-wide.

• Archives of design research
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• v.17 no.4
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• pp.177-190
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• 2004

The purpose of this study is to provide domestic small and medium manufacturing businesses with effective ways of introducing and promoting design management, earnestly, as a key strategy for raising corporate competitiveness. For the purpose, this researcher discussed the management property of small and medium businesses, the introducing process and method and the necessity of promoting design management in small and medium businesses. Then the researcher reviewed and analyzed existing empirical studies to know the current status of design introduction and design management promotion i domestic small and medium businesses. Results of the study can be described as below. Prerequisite to the successful introduction by domestic small and medium businesses of design management are three CEO determinations - the firm will to the necessity of design introduction, the firm conviction in design efficacy, and the clear recognition of the existential value of design - and the establishment of at least five infrastructures -design organization, CDO, designers, design policy, and design strategy. For the promoting and succeeding in the execution of design management, design management system should have established based on such determinations and infrastructures, and CEOs should have design management mind firmly established and driven and realized next activities in the process of product development. 1) Set the principle of design priority in a new product development and establish an appropriate production system and environment. 2) Decide a new design development as the top-priority task of management and then practice it in a strategic way. 3) Be positive in design investment while accepting design management as a concept related not to cost, but to investment. 4) Utilize design extensively under the understanding that design management has something to do with corporate design system as a whole. 5) Treat design as the most valuable resource of business under the recognition that design is the most important determinant of corporate competitiveness.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.2
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• pp.151-158
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• 2011

This study was carried out in 2010 to investigate the utilization and nutritive value of native grasses, such as Phragmites communis and Miscanthus sinensis which might reduce the cost of feeding domestic cattle. The regions within the Civilian Control Line in Paju and Sihwa region in Ansan were surveyed. In Paju, the yearly silage production was 900 MT harvested from 90 ha (10 MT/ha). About 30~50% of these were sold out at the marketing price of 52,000~55,000 Won per roll (130~137.5 Won/kg). Regrown Miscanthus sinensis of 70 cm in length contained 9.6% of crude protein (CP), 82.4 of relative feed value (RFV), and 67.7% of in vitro dry matter digestibility (IVDMD). Regrown Phragmites communis of 70 cm in length contained 13.8% of CP, 84.3 of RFV, and 67.9% of IVDMD. As harvesting was delayed, the quality was decreased dramatically. In Ansan region, Phragmites communis plantation covers 100 ha. The silage production was 550 MT from the area of 50 ha (11 MT/ha) in 2009. And the marketing price was 50,000 Won per roll. But in 2010 only a small amount of grasses could have been baled due to frequent and much rainfall from spring to summer season. However, the good forage quality was observed from regrown Phragmites communis of 80 cm in length, 12.9% CP, 99.8 RFV and 66.6% IVDMD, while that of late matured grasses was very low, 2.2% CP, 52.9 RFV and 36.4% IVDMD, greatly lower than forage quality of rice straw. The quality of grasses at bloom stage of 150 cm in length was similar to that of rice straw, showing 4.5% CP, 59.9 RFV and 42.2% IVDMD. In conclusion, the overall quality of most native grasses in this survey were very poor. Therefore, we recommend that Phragmites communis and Miscanthus sinensis should be harvested during June or July to obtain better forage quality which is richer in forage values than rice straw. Production of high quality forage crops was also desirable for self sufficiency of forage.

• Journal of the Korean Ceramic Society
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• v.38 no.10
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• pp.908-913
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• 2001

Paper sludge Ash (PA) and Fly Ash (FA) wastes are usually land-filled for reclamation or substituted for cements as a resource. It could also offer some advantages when they are substituted for clay to preserve the environment. To recycle those wastes, the sintered specimen made of PA-FA-Clay system were examined to find the microstructure and physical properties. The ratio of clay to wastes was fixed as 30:70 by wt%, while PA to FA within waste portion were varied in the range of $1:6{\sim}7:0$. Those specimens were fired in $1150{\sim}1350^{\circ}C$. It was found that the relative density of sintered specimen was increased with amount of PA added at low sintering temperature (i.e, $1150{\sim}1200^{\circ}C$). This is due to increased amount of liquid during sintering. It is shown, however that at high sintering temperature ($1250{\sim}1350^{\circ}C$), the relative density of specimens was decreased with amount of PA added. This is because of overfiring phenomenon which may be able to induce an inhomogeneous microstructure and increased porosity. The mechanical properties of sintered specimen were depended upon the homogeneity of microstructure in accordance with SEM (Scanning Electron Microscopy) and pore size distribution analysis. For example, the compressive strength of 10PA-60FA-30Clay specimen sintered at $1225^{\circ}C$ was twice higher than that of 70PA-30Clay specimen even thought the relative density of those specimen was similar. This decreased strength of 70PA-30Clay specimen appears to be an inhomogeneity of microstructure due to overfiring.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.388-395
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• 2016

This paper explores the photocatalytic sensitivity of cement mortar incorporated with recycled $TiO_2$ from waste water sludge. Basically, $TiO_2$ cluster sank down slowly to the bottom of cement mortar specimen before setting and hardening process. This leads the mismatch of $TiO_2$ concentration on the top and the bottom faces of a specimen. This poorly dispersed $TiO_2$-cement mortar naturally exhibits poor NOx removal efficiency especially on the top of cementitious structure. In architectural engineering application such as building or housing structures, one can simply filp over from the bottom so that more $TiO_2$ concentrated surface can be placed outward into the air. However, in highway pavement case, this could not be applicable due to in-situ installation of concrete pavement. Hence, the dispersion of $TiO_2$ cluster inside the cementitous material is getting important issue onto road construction application. To elaborate this issue, according to our results, silica fume, high-ranged water reducer, viscosity agent, blast furnace slag were not enhanced much of dispersion characteristics of $TiO_2$ cluster. The combination of foaming agent and accelerator of hardening with viscosity agent and small grain size of fine aggregate may help the dispersion of $TiO_2$ inside cementitious materials. Even though the enhanced dispersion were applied to the specimen, NOx removal efficiency doest not change much for the top surface of the specimen. This concurrently affected by the presence of tiny air voids and the dispersion of $TiO_2$ in that these voids could easily adsorbed NOx gas with the aid of large surface area.