• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.802-804
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• 2003

The relative stabilities of weak binding clusters are sensitive to temperature due to the entropy effect. Thus, here we report significant changes in relative stabilities between two low-energy electron-water trimer structures and those between three low-energy electron-water pentamer structures, as the temperature increases. The trimer and pentamer show structural changes around 200 K.

• Journal of the Korean Professional Engineers Association
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• v.41 no.3
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• pp.30-34
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• 2008

Recently problems of soil and groundwater contamination occur in major construction sites of highway, dam and railways. Contaminants of oil fuels are also detected in the former fuel storage facilities of railroad station and army troops of transportation, etc. These facilities are planned as the sites of commercial infrastructures after restoration from pollutants by the law of soil environment conservation of Korea. In this manuscript, the contents of soil environment conservation law including soil assessment and restoration technology are introduced. Recent changes of soil environment area are also analyzed.

• Journal of Science and Technology Studies
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• v.9 no.2
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• pp.79-102
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• 2009

This study reviews the issue of public interests of technologies required in industrial technology policy as well as the demand for changes in industrial technology policy as result of the migration from catch-up to post catch-up innovation system. In fact, the importance of public interests which served as the rationale for government intervention in industrial technology policy have gradually faded, which invited controversies over the legitimacy and effectiveness of government intervention in promoting specific technologies or industries. Today, the existing policy framework has to change to correspond to the post catch-up environment which requires creative technology development. In this context, the Korean government needs to reduce direct support for certain companies or technologies, but increase R&D investment in energy, environment and health and welfare to enhance public interests of technology innovation activities.

• Molecules and Cells
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• v.40 no.7
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• pp.495-502
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• 2017

The $5-HT_6R$ has been considered as an attractive therapeutic target in the brain due to its exclusive expression in the brain. However, the mechanistic linkage between $5-HT_6Rs$ and brain functions remains poorly understood. Here, we examined the effects of $5-HT_6R$-mediated cell morphological changes using immunocytochemistry, Western blot, and live-cell imaging assays. Our results showed that the activation of $5-HT_6Rs$ caused morphological changes and increased cell surface area in HEK293 cells expressing $5-HT_6Rs$. Treatment with 5-HT specifically increased RhoA-GTP activity without affecting other Rho family proteins, such as Rac1 and Cdc42. Furthermore, live-cell imaging in hippocampal neurons revealed that activation of $5-HT_6Rs$ using a selective agonist, ST1936, increased the density and size of dendritic protrusions along with the activation of RhoA-GTP activity and that both effects were blocked by pretreatment with a selective $5-HT_6R$ antagonist, SB258585. Taken together, our results show that $5-HT_6R$ plays an important role in the regulation of cell morphology via a RhoA-dependent pathway in mammalian cell lines and primary neurons.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.86-87
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• 1993

The steeping of waxy rice in water at $20^{\circ}C$ for 12 hr resulted in the decrease of protein, crude fat and ash contents. Water-binding capacity and swelling power (at $80^{\circ}C$) of waxy rice flour increased upon steeping. Maximum viscosity of waxy rice flour in 0.19 N sodium hydroxide solution was increased up to 6 hr steeping and decreased thereafter. The amylograph indices increased as the steeping time increased. The degree of changes in properties during steeping was different between two waxy rice cultivars.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.7
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• pp.112-120
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• 2020

During the past decades, dramatic technology changes affected the life of billions of people around the globe. Although these changes resulted to economic benefits, mostly for the developed countries, the undiscerning development also resulted to many side effects, such as environment pollution, scarce natural resources, global warming, and an increase of the gap between "those who have" and "those who have not", among others. Also, since these developments were based on high technologies, they were not suitable for 90% of the underdeveloped countries. In this review, the possible ways of increasing the quality of life in underdeveloped countries are described, by providing adaptive solutions using appropriate technologies. Some successful applications of appropriate and intermediate technology are introduced, and the need for a new undergraduate education course of engineering design based on appropriate technology is proposed for Korea.

• Corrosion Science and Technology
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• v.15 no.6
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• pp.259-264
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• 2016

With a specially designed electrochemical cell, the changes in impedance behavior for Inconel 600 and aluminide diffusion coatings under molten sulfate film with thermal cycles (from $800^{\circ}C$ to $350^{\circ}C$) were monitored with electrochemical impedance measurements. It was found that corrosion resistance for both materials increased with lower temperatures. At the same time, the state of molten salt was also monitored successfully by measuring the changes in impedance at high frequency, which generally represents the resistance of molten salt itself. After two thermal cycles, both Inconel 600 and aluminide diffusion coatings showed excellent corrosion resistance. The results from SEM observation and EDS analysis correlated well with the results obtained by electrochemical impedance measurements. It is concluded that electrochemical impedance is very useful for monitoring the corrosion resistance of materials under molten salt film conditions even with thermal cycles.

• Journal of the Semiconductor & Display Technology
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• v.9 no.4
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• pp.71-76
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• 2010

According to recent changes in industry for semiconductor devices, a low-temperature treatment has become a necessity. These changes relate to size refinement and the development of new materials. While variation in cooling efficiency does not affect the yield when using a high-temperature treatment, uniform cooling efficiency is necessary avoid "inconsistencies/bends" in low temperature treatments. However it is difficult to increase temperature stabilization in low temperature treatments. In this paper, using CFD (Computer Fluid Dynamics), we analyze and manipulate the design and input of the low-temperature system to attempt to control for temperature variations within the quartz tube, of which airflow appears to be a predominant factor. This simulation includes variable inputs such as airflow rate, head pressure, and design manipulations in the S.C.U. (Super Cooling Unit).

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.55-59
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• 2024

Plasma Enhanced Chemical Vapor Deposition (PE-CVD) is a widely used technology in semiconductor manufacturing for thin film deposition. The implementation of wafer guide rings in PE-CVD processes is crucial for enhancing efficiency and product quality by ensuring uniform deposition around wafer edges and reducing particle generation. On the other hand, to prevent overall temperature non-uniformity and degradation of thin film quality within the chamber, it is essential to consider various parameters comprehensively. In this study, after applying the wafer guide rings, temperature variations and fluid flow changes were simulated. Additionally, by simulating the temperature and flow changes when applied to the PE-CVD chamber, this paper discusses the importance of optimizing variables within the entire chamber.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.4
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• pp.75-90
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• 2010

The purpose of this study is to identify landscaping costs for apartment landscapes, landscape facility factors, and the transition of spatial composition for landscapes. In addition, based on the questionnaires and analysis results for workers in related fields such as landscape design companies and construction companies, this study aimed at acquiring results for the development of current apartment landscapes and directions for improvement in the future. Through the results, it aimed at providing basic data for apartment landscapes in the future. Results showed that there was approximately a 2.6 times increase for landscaping expenses of actual apartment landscapes, and a 7.0 to 11.5 times increase in the future can be expected. The cause of such increase is the continuously growing demand for a more pleasant environment. Landscape facilities factors have been diversified, and most facilities are used as multi-purpose spaces rather than serving simple facilities. Questionnaires and field investigations showed that water facilities underwent the biggest changes, and the cause for such changes were found to be the introduction of new facilities such as water facilities and environmental structures, as well as the creation of integrated functions and spaces. Spatial composition for landscapes showed that multi-purpose spaces were established, and for the apartment differentiation strategy, there were many different changes such as theming of green areas and places for exchange among residents. For changes, the most changes were in green areas, and studies also showed that there were many changes for rest areas as well. The cause for such change is judged to have been brought about by the increase of landscape space by placing parking areas underground, and investigations showed that compared to green areas composed of large grass patches, recent apartments are establishing diverse and experience-based green areas.