• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.228-234
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• 2016

The aim of this study was to develop pharmaceutical dosage forms with a bi-phasic drug using a double extrusion approach. Hot melt extrusion was performed using a co-rotating twin-screw extruder. The. 1st melt extrusion was performed using polymer with a relatively higher Tg, such as HPMC and the 2nd melt extrudate was obtained using the 1st extrudate and polymers with a lower Tg, such as HPMC-AS and PEO. In addition, the formulation with all the content in the same proportion as the double extudate was produced using single extrusion for comparison. Physical characterization was performed on the formulations employing differential scanning calorimetry (DSC). In vitro release tests were studied using a USP Type-I apparatus at $37{\pm}0.5^{\circ}C$ and 100 rpm. The similarity factor (f2) was also used to check the difference statistically. The DSC results indicated that the crystallinity of ibuprofen was changed to an amorphous state after extrusion in both double and single melt extrusion. Double melt extrudate with ibuprofen showed the desired release in acidic media (pH 1.2) in the first two hours and basic (pH 6.8) during six hours. Double melt extrudate with glimepiride showed faster release in 60 min of over 80%, whereas the single extrudate with glimepiride showed retarded release due to the interaction with HPMC. The similarity factor(f2) value was 28.5, which demonstrates that there were different drug release behavior between the double and single extrusion. Consequently, the double melt extrudated formulation was robust and gave the desired drug release pattern.

• Journal of KIISE:Databases
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• v.28 no.4
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• pp.529-544
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• 2001

Prefetching is an effective method to minimize the number of roundtrips between the client and the server in database management systems. In this paper we propose new notions of the type-level access pattern and the type-level access locality and developed an efficient prefetchin policy based on the notions. The type-level access patterns is a sequence of attributes that are referenced in accessing the objects: the type-level access locality a phenomenon that regular and repetitive type-level access patterns exist. Existing prefetching methods are based on object-level or page-level access patterns, which consist of object0ids of page-ids of the objects accessed. However, the drawback of these methods is that they work only when exactly the same objects or pages are accessed repeatedly. In contrast, even though the same objects are not accessed repeatedly, our technique effectively prefetches objects if the same attributes are referenced repeatedly, i,e of there is type-level access locality. Many navigational applications in Object-Relational Database Management System(ORDBMs) have type-level access locality. Therefore our technique can be employed in ORDBMs to effectively reduce the number of roundtrips thereby significantly enhancing the performance. We have conducted extensive experiments in a prototype ORDBMS to show the effectiveness of our algorithm. Experimental results using the 007 benchmark and a real GIS application show that our technique provides orders of magnitude improvements in the roundtrips and several factors of improvements in overall performance over on-demand fetching and context-based prefetching, which a state-of the art prefetching method. These results indicate that our approach significantly and is a practical method that can be implemented in commercial ORDMSs.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.938-946
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• 2017

This study was conducted to examine the changes in serum lipid components and blood glucose by krill (Euphausia superba) meal and sodium fluoride (NaF) in rats fed on experimental diets and administered orally to NaF 10 mg for 5 weeks. Body weight of rats decreased as the amount of krill meal diet increased, it was observed the basal diet plus NaF group (BF group) compared to the lower basal diet group (BD group). The serum concentrations of total cholesterol, LDL (low-density lipoprotein) cholesterol, free cholesterol, triglyceride (TG), phospholipid (PL) and blood glucose in serum were higher in the BF group than the 10% krill meal group plus NaF 10 mg (KF10 group) or BD group, the 20% krill meal plus NaF 10 mg group (KF20 group), the 30% krill meal plus NaF 10 mg group (KF30 group). Conversely depending on the content of krill meal for the HDL (high-density lipoprotein) cholesterol level, it showed higher results. The concentration of total protein was no significant difference among the groups (p<0.05). The results indicate that a krill meal diet effectively inhibited increases in lipid elevation and blood glucose level in the sera of rats.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.41 no.4
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• pp.315-324
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• 2015

In this study, we prepared liquid crystal emulsion composed of amphiphilic substance $C_{14-22}$ alcohol, $C_{12-20}$ alkyl glucoside, behenyl alcohol and studied liquid crystal emulsion of properties and in vitro skin permeation. The results of formulation experiments, the clear liquid crystalline structure was observed in the ratio of $C_{14-22}$ alcohol 0.8%, $C_{12-20}$ alkyl glucoside 3.2%, behenyl alcohol 4% in the formulation. The results of physical property measurements, the viscosity of liquid crystal emulsion and O/W emulsion applied as a control group was respectively $1871.26{\sim}1.15Pa{\cdot}s$, $1768.69{\sim}1.14Pa{\cdot}s$ and the shear stress of O/W emulsion was 178.68 ~ 909.18 Pa, that of liquid crystal emulsion was 190.45 ~ 919.38 Pa. The storage modulus of O/W emulsion was 3428.53 ~ 9157.45 Pa, that of liquid crystal emulsion was 4487.82 ~ 8195.59 Pa. The tan (delta) value of O/W emulsion which means a ratio of viscosity to elasticity was 0.43 ~ 0.19, and that of liquid crystal emulsion was 0.23 ~ 0.25. The water content value on the skin for liquid crystal emulsion was significantly higher from 1 h to 6 h compared with that of O/W emulsion and the transepidermal water loss on the skin was significantly superior in skin moisture loss suppression from 30 min to 4 h compared with that of O/W emulsion. The results of skin permeation using glycyrrhizic acid, the result of skin permeation amount of liquid crystal emulsion for 24 h was $64.58{\mu}g/cm^2$, that of O/W emulsion was $37.07{\mu}g/cm^2$, that of butylene glycol solution was $41.05{\mu}g/cm^2$. Hourly permeability results, it is showed that skin penetration effect of the liquid crystal emulsion increases after 8 h. These results suggest that liquid crystal emulsions are effective for skin moisturizing effect and function as potential efficacy ingredient delivery system for the transdermal delivery.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.667-673
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• 2011

There is relatively high vulnerability of soil erosion in slope highland agriculture due to a reclamation of mountain as well as low surface covering in early summer season with high rainfall intensity time. The aim of this study was to evaluate various surface covering methods for reducing soil loss in highland radish cultivation in highland. The experiment was conducted in 17% sloped lysimeter ($2.5m{\times}13.4m$) with 8 treatments including covering with cut rye, sod culture of rye, Ligularia fischeri var. spiciformis Nakai, Arachniodes aristata Tindale, Aster koraiensis Nakai, Festuca myuros L. and mulching with black polyethylene film, and runoff water, eroded soil and radish growth were investigated. Surface covering with sod culture and plant residue, especially cut rye treatment, had lower runoff water than non-covering, whereas black polyethylene film mulching had the reverse. The amount of eroded soil was also lowest in cut rye treatment, $0.3Mg\;ha^{-1}$, and increased in the order of rye sod culture, Ligularia fischeri var. spiciformis Nakai, Aster koraiensis Nakai, Festuca myuros L., Arachniodes aristata Tindale, black polyethylene film, and non-covering, $68.2Mg\;ha^{-1}$. The results showed that surface covering with sod culture or plant residue could be effective for reducing runoff water and soil erosion in the radish field, significantly in cut rye treatment. On the other hand, in sod culture of rye, Aster koraiensis Nakai and Ligularia fischeri var. spiciformis Nakai, radish yields were lower than in the non-covering. Unlike this, covering with cut rye, sod culture of Festuca myuros L. had similar radish yield to the non-covering radish yield. In conclusion, covering with cut rye and sod culture of Festuca myuros L. were beneficial for reduction of soil loss without decreasing in radish yield in highland sloped fields.

• Korean Journal of Remote Sensing
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• v.37 no.6_1
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• pp.1631-1645
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• 2021

This research aims to provide the characteristics of the world's first active lidar sensor Atmospheric Laser Doppler Instrument (ALADIN) wind data and Geostationary Korea Multi Purpose Satellite 2A (GK2A) Atmospheric Motion Vector (AMV) data by comparing two wind data. As a result of comparing the data from September 2019 to August 1, 2020, The total number of collocated data for the AMV (using IR channel) and Mie channel ALADIN data is 177,681 which gives the Root Mean Square Error (RMSE) of 3.73 m/s and the correlation coefficient is 0.98. For a more detailed analysis, Comparison result considering altitude and latitude, the Normalized Root Mean Squared Error (NRMSE) is 0.2-0.3 at most latitude bands. However, the upper and middle layers in the lower latitudes and the lower layer in the southern hemispheric are larger than 0.4 at specific latitudes. These results are the same for the water vapor channel and the visible channel regardless of the season, and the channel-specific and seasonal characteristics do not appear prominently. Furthermore, as a result of analyzing the distribution of clouds in the latitude band with a large difference between the two wind data, Cirrus or cumulus clouds, which can lower the accuracy of height assignment of AMV, are distributed more than at other latitude bands. Accordingly, it is suggested that ALADIN wind data in the southern hemisphere and low latitude band, where the error of the AMV is large, can have a positive effect on the numerical forecast model.

• Journal of the Korean Applied Science and Technology
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• v.38 no.6
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• pp.1687-1698
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• 2021

This study is to produce multiple layers of liposomes in a supercritical state and encapsulates active ingredients in order to stably encapsulate thermodynamically unstable active ingredients. In order to form a liposome in a supercritical state, a mixed surfactant development including vegetable-derived hydrogenated phosphatidyl choline and their delivative, hydrogenated sucrose distearate was synthesized as high purity. It describes a manufacturing method of injecting liquid carbon dioxide into a reactor to create a supercritical state and stirring to produce a giant liposome, and adding and loading genistein and quercetin. The HLB of the mixed lipid complex (SC-Lipid Complex) was 12.50, and multiple layers of liposome vesicles were formed even at very low concentrations. This surfactant had a specific odor with a pale yellow flake, the specific gravity was 0.972, and the acid value was 0.12, indicating that it was synthesized with high purity. As a result of the emulsifying capacity experiment using 20 wt% capric/capric triglyceride and triethylhexanoin using SC-Lipid Complex, it was found to have 96.2% emulsifying power. SC LIPOSOME GENISTEIN was confirmed that a multi-layer liposome vesicle was formed through a transmission electron microscope (Cryo-TEM) for the supercritical liposome encapsulated with genistein. The primary liposome particle size in which genistein was encapsulated was 253.9 nm, and the secondary capsule size was 18.2 ㎛. Using genistein as the standard substance, the encapsulation efficiency of supercritical liposomes was 99.5%, and general liposomes were found to have an efficiency of 93.6%. In addition, the antioxidant activity experiment in which quercetin was sealed was confirmed by the DPPH method, and it was found that the supercritical liposome significantly maintained excellent antioxidant activity. In this study, thermodynamically unstable raw materials were sealed into liposomes without organic solvents in a supercritical state. Based on these results, it is expected that it can be applied to various forms such as highly functional skincare cosmetics, makeup cosmetics, and scalp protection cosmetics.

• (The) Research of the performance art and culture
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• no.37
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• pp.249-293
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• 2018

The Musical Theatre was a popular art genre that originated from the western musical tradition represented by the European opera. In the twentieth century, it bloomed around Broadway in the United States. It is also one of the commercial arts which is popularly loved by the public in the field of performing arts all over the world at present. Due to the nature of this genre, the development of dramas and the expression of characters use music, not words or gestures, as the main medium. And the style of music reacts sensitively to the taste of the public, not to a particular class. When Japan colonized Korea, the empire strongly believed modernization equaled westernization and Japan was the one who could awaken Korean. The Japanese colonial music education was intended to bring cooperation and obedience to Japan by forcibly injecting Japanese ideology and culture into Joseon people. The music education of colonialism with the textbook of the "Songs for public education(보통교육 창가집)" compiled by the Japanese government was a sparkstone for the conversion of the Korean musical identity to Japanese and Western music. In addition to the capitalistic economical mechanism for establishing a South Korean government friendly with the United States during the Cold War after liberation, and the rush of American Pop culture represented by 'the show stage in 8th US Arm' and 'movies' which are to be the influence of invisible 'new cultural imperialism', our traditional music was confined to the meaning of 'Korean music', meaning 'past music'. In Korea, after the liberation, the musical was introduced by the influx of American popular culture. In accordance with the cultural policy of Park Jeong-hee regime, which aimed to spread the 'healthy culture' through the modernization of traditional arts, 'The Yegreen(예그린악단)' was founded. However, the plan to create a contemporary performing art based on Korean national arts showed the possibility of success in 1966 with the success of , but soon after, they have been destined to fall into an institution that has lost their ability to operate on their own due to the suspension of the sponsorship of the regime. Due to the cultural imperialist strategy of the influence of Japanese imperialism's colonial music education and influx of American popular culture after liberation, in the early days of Korean musicals, our traditional aesthetic style brought about the situation of the 1960 's, which did not become an independent ethnic art through the exchange and expansion with Western music. This is the background of the western licensed musicals led by the Korean musical market in the 21st century as well as the main cause of musical creation based on western music.

• Journal of Korean Philosophical Society
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• v.116
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• pp.1-31
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• 2010

This Article studies a meaning of geometrical-mathematical spatial idea in the source of modern theories of space. Modern theories of space elucidated a relation of human and space through the geometrical terms; point, line, plane and extension etc. Descartes and Newton identified space as a natural realty, Leibniz and Kant elucidated space as a subjective idea or form. It is the result of modern spatial theories that space is lied nearly in human. In the meaning of natural space, space is empirically unfolded with a shape of measuring in front of human's eyes. In the meaning of cognitional space, space is a method or subjective cognitional form that human understands nature and constitutes world. Modern theories of space would be divided into four patterns. In Newton's theory space is absolutely prior to things. In Leibniz' theory space is a co-existence order of Monads. In Descartes's theory space is identified with extension. In Kant's theory space is cognitional form of subject. They all are confronted with each other in the source of space. In their confrontation they reflected on the relation of human and space in their own standpoint. We classify their particularly differential concepts of space into natural space and cognitional space. And then we analyze a difference of spatial meanings, and then investigate foundations of meaning of modern theories of space. On the one hand they are become to the source of alienation of human from space. But on the other they are contributed to get space familiar with human through a wakening for the correlation of human and space. The natural space indicates that with measurable shape space is extended really in front of human's experiential eyes. But the cognitional space elucidates that space is only a subjective idea or form with which human understands nature and constructs world. In the former it is embossed that space is independent to human, and is able to be measured and to be treated according to natural raws. In the latter it is evidenced that space is not separated to human, and that space is not without human, and a correlation existed between human and space. Humanist ideal is declared in them. It was a declaration of human sovereignty to nature. But this declaration is caused to alienate human beings from space.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.543-548
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• 2011

Haiami is a new Japonica rice variety developed from a cross between 'Jinmibyeo' TR treated with ethyl methane sulfonate (EMS) EMS and 5-methytryptophan, and 'Gyehwabyeo' in order to develop a new premium quality rice variety by a rice breeding team of National Institute of Crop Science, Rural Development Administration in 2008. This variety has about 138 days of growth duration from transplanting to harvesting in central plain area of Korea. The heading date of this vareity was on $15^{th}$, August. The 'Haiami' has good semi-elect plant type and resistant to lodging with strong culm. The number of panicles/hill of 'Haiami' is more than that of 'Hwaseongbyeo'. This variety shows slow leaf senescence and considerable tolerance to viviparous germination. It is susceptible to leaf blast, bacterial blight, and insect pests, but resistance to rice stripe virus. The milled rice of this variety exhibited translucent, clear non-glutinous endosperm and short grain shape. The essential amino acid properties of 'Haiami' have more than 31% that of 'Hwaseongbyeo' in polished rice. This variety has premium palatability of cooked rice. The yield performance of this rice cultivar was about 5.38 MT/ha in milled rice in local adaptability test for three years from 2006 to 2008. 'Haiami' is adaptable to central and southern plain areas of Korea.