• Journal of Pharmaceutical Investigation
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• v.41 no.1
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• pp.25-30
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• 2011

Recently, Korean Food and Drug Administration (KFDA) has focused on developing quality control guidelines for all commercial products in Korea to enforce regulations, improve the quality control, and protect consumers by developing prevalently used and efficient analytical tools to determine and quantify target compounds. Because the Korean Pharmacopeia (KP) presents microbiological assays for biotin, which is laborious and time-consuming, this study is focused on applying HPLC-UV to detect and quantify biotin in complex drugs and dietary supplements like multi-vitamin. Biotin in complex drugs was extracted from methanol and analyzed using mobile phase with 10 mM potassium phosphate (monobasic, pH=3.0) in distilled water and acetonitrile. Gradient condition was used to successfully detect and quantify biotin within 20 minutes. Validation result for linearity was significant that average $r^2$ was 0.999 (n=3) and its relative standard deviation (RSD) was 0.0578% which was less than 2%. Using this method, quantification of biotin in complex drugs was completed successfully and recovery tests were finished that recovery percentage greater than 95% with relative standard deviation less than 2%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.125-129
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• 2001

Eight vermiculite-based root media prepared with addition of complete fertilizer (2 g/L; N-$P_2$$O_5$-$K_2$O, 10-10-14) for potatoes (Solanum tuberosum L.) and a commercial root medium were evaluated in 2000 to develop the root media suitable for potato plug seedling production. The eight media consisted of various ratios of vermiculite, perlite, peatmoss, and compost. In addition, four rates (0, 1, 2, or 4 g/L) of the complex fertilizer for potato were added to a root medium (70% vermiculite, 10% perlite, 10% peat moss, and 10% compost by volume) to determine the optimum addition rate of the complex fertilizer for plug seedlings. Compost addition to the media increased plant height, the number of leaves per plant, and top and root fresh weight of 15-day old plug seedlings. The seedlings raised in root media containing compost produced significantly higher total tuber yield. Addition of the complex fertilizer to root media enhanced seedling growth and increased the number of tubers per plant and tuber yields. The results suggest that root media containing 50% vermiculite, 0 to 20% peat moss, 10% perlite, 20 to 40% compost, and 2 g/L complex fertilizer for potato appear suitable for potato plug seedling production.

• Proceedings of the SAREK Conference
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• 2008.11a
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• pp.151-156
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• 2008

Water flow characteristics of an apartment complex consisting of 12 buildings and 635 units in total have been investigated numerically. The complex incorporates two zone booster pump water supply system, and some units have pressure reducing valves in them. Input data to a commercial code Flowmaster7 include survey results on the water usage for the last three years, dimension of the water supply system and its operation condition, etc. Calculated static pressures at the inlet of all units are compared with their design and measured counterparts, and they agree quite well with each other. Then, the pressure distributions and volumetric flow rates at all 635 units are estimated. Flow balancing is also attempted by varying the ratio of angle valve of each unit to improve the non-uniformity of flows.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.31-36
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• 1995

Solid dispersions and inclusion complex were prepared for the enhancement of solubility and dissolution rate of poorly water-soluble ibuprofen(IPF) as a model drug. Polyethylene glycol 4000(PEG4000) and polyvinylpyrrolidone(PVP) were used for the preparation of solid dispersion. $2-Hydroxypropyl-{\beta}-cyclodextrin(2-HP{\beta}CD)$ was also used for the preparation of inclusion complex. The solubility of IPF increased as the concentration of PEG4000, PVP and $2-HP{\beta}CD$ increased. Solubilization capacity of $2-HP{\beta}CD$ was increased about 10 times when compared to PEG 4000 and PVP. The dissolution rate of drug from solid dispersions and inclusion complex in the simulated gastric fluid was enhanced when compared to pure IPF and commercial $BR4^{\circledR}$ tablet as a result of improvement of solubility. In case of solid dispersions, dissolution rate of drug was proportional to polymer concentration in the formulation. The marked enhancement of dissolution rate of drug by inclusion complexation with $2-HP{\beta}CD$ was noted. However, dissolution rate of drug from solid dispersions and inclusion complex in the simulated intestinal fluid was not significant because IPF was readily soluble in that condition. From these findings, water-soluble polymers and cyclodextrin were useful to improve solubility and dissolution rate of poorly water-soluble drugs. However, easiness and reliability of preparation method, scale-up and cost of raw materials must be considered for the practical application of solid dispersion and inclusion complex in pharmaceutical industry.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.367-373
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• 2019

In modern society, with the changing lifestyle, demand for complex cultural spaces is rising and various cultural spaces are emerging. However, user-centered cultural space research has not yet been shown. In order to find out whether various cultural experience functions and user experience types of complex cultural spaces are being delivered properly, this study compared and analyzed the representative cultural spaces of Korea, 'Starfield Library' and 'ARC.N.BOOK'. User experience analysis tools and individual in-depth interviews were used as research methods. As a result, both spaces responded that commercial space and brand library were out of harmony and that the use of services in complex cultural spaces was inconvenient. This is interpreted as the result of the need for improvement measures in the value and usability of experience provided by the current complex cultural space and is expected to help develop the complex cultural space in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.89-106
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• 2020

This study examines the functionality and landscape design specifics of the outdoor space of representative commercial multi-complexes in Korea in order to overview the design trends of outdoor landscaping trends. Through surveying the composition of outdoor spaces along with their relation to the surrounding landscape, open spaces, and the neighboring communities, this paper identified the change in trends regarding the characteristics of outdoor landscape planning and acknowledged the enhanced public value of outdoor space. This study asserts that the characteristics of outdoor spaces can best be understood by examining the ways in which the outdoor space relates to adjoining commercial multi-complexes and the surrounding landscape. Focusing on the relationships that outdoor space establishes, commercial multi-complexes can be categorized as follows: in/outdoor separated type, in/outdoor semi-open type, surrounding landscape-projected type, and surrounding landscape-combined type. By studying the landscape design specifics of the outdoor space of representative cases of each type, the following has been concluded: First, the amount of outdoor space has expanded in terms of importance and function while serving to assist in various activities and participatory experiences, and no longer merely serves as a backdrop of commercial facilities. Second, with the strengthened connectivity between in/outdoor spaces, the elements of outdoor surroundings are more actively introduced indoors to improve amenities. Through directly connecting certain indoor program spaces with outdoor spaces, commercial multi-complexes tend to provide richer combined experiences. Third, with the expansion of outdoor space functionality, commercial multi-complexes are increasingly recognized as a quasi-public space, making good example of liminal space. In light of the recent case of development plans linked with public open spaces in suburban settings, commercial landscape design shows the possibility of creating an open space that can function as a center for local culture and green networks in the community.

• Journal of Arbitration Studies
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• v.29 no.2
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• pp.3-34
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• 2019

The resumption of economic cooperation between South and the North Korea will be a new growth engine for our economy. Many Korean companies are preparing to invest in North Korea in accordance with the progress of inter-Korean relations. However, there are many risks inherent in inter-Korean economic cooperation, as experienced in previous cases. Specifically, one should be prepared for unfair measures such as the expropriation of investment assets of South Korean enterprises by North Korea authorities. Therefore, it is essential to review the protection measures of investment in North Korea and to review the investment dispute settlement system. The South and the North have an agreement to establish the inter-Korean Commercial Arbitration Committee to resolve the disputes that may arise if one party's investments are lost due to inappropriate or unfair measures due to the other party's authority. However, the Investment Agreement, which governs the Inter-Korean Commercial Arbitration Committee, contains a number of declarative statements that are somewhat ineffective. Even today, nearly 20 years after the adoption of the Agreement, the specific detailed procedures have shown no real progress, such as in the enactment of arbitration rules. Therefore, at present, it is difficult to expect a system that can effectively address the damage of our corporations which have invested in North Korea. When the assets freeze after the suspension of Kumgang tourism and the closure of the Kaeseung Industrial Complex by North Korea, the activation of the inter-Korean Commercial Arbitration Committee is the most important prerequisite for economic cooperation with North Korea. For this purpose, the resolution of disputes through the Inter-Korean Commercial Arbitration Committee has to be made more concrete, with the effectiveness of the dispute settlement system enhanced by means of various efforts.

• Journal of Korea Foundry Society
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• v.22 no.4
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• pp.192-199
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• 2002

Dimensional defects of castings are mainly due to the stresses and strains caused by a nonuniform temperature distribution and phase transformation during solidification and cooling, and by mechanical constraint between the mold and casting. It is, however, nearly impossible to trace movements of the casting and mold during solidification and cooling by experimental measurements for castings with complex shape. Two and three dimensional deformation analyses of the casting and the mold were performed using commercial finite element code, MARC. It was possible to calculate deformation and temperature distribution in the casting and mold simultaneously. Cooling curves of the casting obtained by calculation were close to that measured in the field since it was possible to treat latent heat evolution of the casting which could be divided into two parts, primary and eutectic parts. Mold bent inward just after pouring due to the temperature gradient across the mold thickness, and mold returned to its previous position with time. Plastic deformation occurred at the part of the casting where solidification was slow.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.207-217
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• 2002

This study was designed to investigate the characteristics of atmospheric concentrations of toxic volatile organic compounds (VOCs) in Korea. Target compounds included 1,3-butadiene, aromatics such as BTEX, and a number of carbonyl compounds. In this paper, as the second part of the study, the seasonal and locational concentrations of atmospheric VOCs were evaluated. Sampling was conducted seasonally at seven sampling sites. each of them representing a large urban area (commercial and residential), a small urban area (commercial and residential), an industrial area (a site within the complex and a residential), and a background place in Korea. In general, higher concentrations were found in the petro-chemical industrial site than other sites, while VOCs measured in commercial (heavy -traffic) sites were higher than residential sites. Seasonality of VOCs concentrations were not so much clear as other combustion related pollutants such as sulfur dioxide, indicating that the VOCs are emitted from a variety of sources, not only vehicle exhaust and point sources but fugitive emissions. Except the industrial site, the concentrations of VOCs measured in this study do not reveal any serious pollution status, since the levels did not exceed any existing ambient standards in the U.K. and/or Japan. However, the increasing number of petrol -powered vehicles and the rapid industrialization in Korea may result in the increased levels of VOCs concentrations in many large urban areas in the near future, if there is no appropriate programme implemented for the control of these compounds.

• International Journal of Control, Automation, and Systems
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• v.3 no.2
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• pp.252-257
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• 2005

In this work, we propose a simple but efficient method to design a target temperature trajectory for pulling speed tracking control of the crystal grower in the Czochralski crystallization process. In the suggested method, the model predictive control strategy is used to incorporate the complex dynamic effect of the heater temperature on the pulling speed into the temperature trajectory design quantitatively. The feedforward trajectories designed by the proposed method were implemented on 200 mm and 300 mm silicon crystal growers in the commercial Czochralski process. The application results have demonstrated its excellent and consistent tracking performance of pulling speed along whole bulk crystal growth.