• Title/Summary/Keyword: 인공 계

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pH Solubility Properties and Improved Dissolution of Pranlukast as an Poorly Water-soluble Model Drug Prepared by Spray-drying with Plasdone S-630 (플라스돈 S-630과 함께 분무건조된 모델 난용성 약물로서 프란루카스트의 pH 용해도 특성 및 용출률 개선)

  • Cho, Won-Hyung;Lee, Young-Hyun;Song, Byung-Joo;Yoo, Seok-Cheol;Lim, Dong-Kyun;Khang, Gil-Son
    • Polymer(Korea)
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    • v.35 no.4
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    • pp.277-283
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    • 2011
  • Solid dispersion is mainly used for improved dissolution of poorly water-soluble drugs. Solid dispersion of pranlukast was prepared by spray-drying with plasdone S-630. When pH of water was high, pranlukast was highly soluble in the solubility experiment of solid dispersions with varying pH. The particle size of pranlukast particles in solid dispersions was measured to be in nanometers scale based on particle size analysis. Zeta-potential analysis confirmed the negative charge of solid dispersion. SEM was used to observe the surface of solid dispersion, which confirmed spherical morphology, DSC and XRD confirmed the amorphous nature of solid dispersions. The in vitro test was carried out to find improved dissolution rate of pranlukast solid dispersion in simulated juice gastric and a controlled experiment was carried out to compare pranlukast solid dispersions with a conventional drug (Onon$^{(R)}$), These results showed the dissolution properties of pranlukast solid dispersions prepared by spray drying proper for the oral pharmaceutical formulation.

A Study on Improvement of Wettability and Comfort in Contact lens with Hyaluronic acid (Hyaluronic acid 함유 콘택트렌즈의 습윤성과 착용감 향상 효과 연구)

  • Kim, Hyun Jung;Kim, Soo-Hyun;Kim, Jai-Min
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.3
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    • pp.255-264
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    • 2011
  • Purpose: To study the effect of hyaluronic acid(HA), which was widely used in artificial tears, multi-purpose solution(MPS), cosmetics, and drug acting on the musculo-skeletal system, in wettability and comfort of contact lens, we compared HA including lens(+HA) with HA excluding lens(-HA) by clinical evaluation. Methods: During four weeks, the selected 28 university student volunteers who did not have any eye disease wore +HA contact lens on their right eyes, and -HA contact lens on their left eyes, and then compared right eyes to left eyes as control. After prescribing by spherical equivalent calculation, over-refraction by auto-refractometer, and contact lens wearing for two weeks and four weeks, tear evaluation, the anterior of eyes examination, fitting convenience evaluation, surface wetting test, surveys were checked up. Results: Compared with the control group (-HA contact lens), +HA contact lens provided better wetting properties. The amount of released tear in -HA contact lens group became less in four weeks than before, but that in +HA contact lens group showed no significant difference from the initial one. In terms of the redness in eye, there was no significant difference between +HA and -HA contact lens groups. Fitting of +HA contact lens on eye was much easier than the control, -HA contact lens. From the results of survey, comfort, wettability, ease of cleaning, and dryness of eye in +HA contact lens group were generally better than those of -HA group, but redness and contact lens handling showed little difference. Conclusions: The addition of HA in soft contact lens(+HA) may enhance the wettability of lens during lens wearing, resulted in the better comfortable wearing of lens eventually.

Characterization of Stress Corrosion Cracking at the Welded Region of High Strength Steel using Acoustic Emission Method (음향방출법에 의한 고 장력강 용접부의 부식손상 특성 평가)

  • Na, Eui-Gyun;Kim, Hoon
    • Journal of the Korean Society for Nondestructive Testing
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    • v.23 no.3
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    • pp.212-219
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    • 2003
  • This study is to evaluate the characteristics of SCC at the welded region of high strength steel using acoustic emission(AE) method. Specimens were loaded by a slow strain rate method in synthetic seawater and the damage process was monitored simultaneously by AE method. Corrosive environment was controlled using the potentiostat, in which -0.8V and -1.1V were applied to the specimens. In the case of one-pass weldment subjected to -0.8V, much more AE counts were detected compared with the PWHT specimen. It was verified through the cumulative counts that coalescence of micro cracks and cracks for the one pass weldment with -0.8V were mostly detected. In case of the one pass weldment subjected to -1.1V, time to failure became shorter and AE counts were produced considerably as compared with that of the two pass weldment. It was shown that AE counts and range of AE amplitude have close relations with the number and size as well as width of the cracks which were formed during the SCC.

Sulfate Reduction in the Marine Environments: Its Controlling Factors and Relative Significance in Mineralization of Organic Matter (해양환경의 황산염 환원율 조절요인 및 유기물 분해에 있어 황산염 환원의 중요성)

  • 현정호;이홍금;권개경
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.8 no.2
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    • pp.210-224
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    • 2003
  • Sulfate reduction is a microbiological process which occurs ubiquitously in anaerobic marine environment. Sulfate reducing bacteria play a significant role in anaerobic decomposition of organic matter and regeneration of inorganic nutrients which supports the primary production in the water column (i.e., benthic-pelagic coupling) and, in special case, could be responsible for the harmful algal bloom in the coastal marine environment. Summary of the sulfate reduction rates reported in various marine sedimentary environments revealed that supply of organic substrates and presence of various electron acceptors (i.e., $O_2$, NO$_{3}$$^{[-10]}$ , Fe(III) and Mn(IV), etc.) for other aerobic and anaerobic respiration directly affect the sulfate reduction rate and relative significance of sulfate reduction in organic matter mineralization. Significance of temperature, macrophytes and bioturbation is discussed as factors controlling supply of organic substrates and distribution of electron acceptors. Finally, we suggest studies on the anaerobic microbiological processes associated with biogeochemical element cycles in the coastal environments of Korea where massive operation of organic enriched fish cage farm, frequent occurrence of toxic algal bloom and hypoxia and conservation of tidal flat are of major environmental issues.

Establishment of Thermal Infrared Observation System on Ieodo Ocean Research Station for Time-series Sea Surface Temperature Extraction (시계열 해수면온도 산출을 위한 이어도 종합해양과학기지 열적외선 관측 시스템 구축)

  • KANG, KI-MOOK;KIM, DUK-JIN;HWANG, JI-HWAN;CHOI, CHANGHYUN;NAM, SUNGHYUN;KIM, SEONGJUNG;CHO, YANG-KI;BYUN, DO-SEONG;LEE, JOOYOUNG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.22 no.3
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    • pp.57-68
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    • 2017
  • Continuous monitoring of spatial and temporal changes in key marine environmental parameters such as SST (sea surface temperature) near IORS (Ieodo Ocean Research Station) is demanded to investigate the ocean ecosystem, climate change, and sea-air interaction processes. In this study, we aimed to develop the system for continuously measuring SST using a TIR (thermal infrared) sensor mounted at the IORS. New SST algorithm is developed to provide SST of better quality that includes automatic atmospheric correction and emissivity calculation for different oceanic conditions. Then, the TIR-based SST products were validated against in-situ water temperature measurements during May 17-26, 2015 and July 15-18, 2015 at the IORS, yielding the accuracy of 0.72-0.85 R-square, and $0.37-0.90^{\circ}C$ RMSE. This TIR-based SST observing system can be installed easily at similar Ocean Research Stations such as Sinan Gageocho and Ongjin Socheongcho, which provide a vision to be utilized as calibration site for SST remotely sensed from satellites to be launched in future.

Breeding of a New Pink Gerbera hybrida 'Party Time' with Strong Peduncle for Cut Flower (단단한 화경의 핑크색 절화용 거베라 신품종 '파티타임' 육성)

  • Chung, Yong Mo;Hwang, Ju Chean;Chin, Young Don;Lee, Jung Soo;Kim, Su Kyeong;Ro, Chi Woong;Yi, Young Byung;Kwon, Oh Chang
    • Horticultural Science & Technology
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    • v.31 no.1
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    • pp.128-132
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    • 2013
  • A new pink gerbera (Gerbera hybrida Hort.) cultivar 'Party Time' was developed from a cross between 'Hope' and 'Sunnyeo', followed by seedling and line selections at the Flower Research Institute of Gyeongnam Agricultural Research and Extension Services (GARES) in 2007. Detailed characteristics of the new cultivar were evaluated from 2005 to 2007. 'Party Time' has semi-double type large flowers in a good harmony with pink (RHS, 65-C) ray floret and brown center. It has a good, stable flower shape and strong peduncles, and its vase life was 12.7 days. The average flower yield of 'Party Time' was about 47.3 stems per plant a year in greenhouse yield trails carried out 2005 to 2007. 'Party Time' (Grant No. 2691) was registered to the Korea Seed and Variety Service (KSVS) for commercialization in 2009.

The Characteristics of Fish Community in the Lagoon Hwajinpo, Korea (화진포호의 어류군집 특성)

  • Park, Seung-Chul;Choi, Jae-Seok;Choi, Eui-Yong;Jang, Young-Su;Lee, Kwang-Yeol;Choi, Jun-Kil
    • Korean Journal of Ecology and Environment
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    • v.40 no.3
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    • pp.449-458
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    • 2007
  • Fish community and its temporal-spacial variation in the Lagoon Hwajinpo, Korea were seasonally investigated with different types of fishing gears from November, 2005 to August, 2006. Total 35.812 fishes caught during the period were belonged to 24 families 37 species. Dominant species was H. nipponensis(60.8%), T, hakonensis (19.8%), and K. punctatus (5.5%) ana these species were peripheral freshwater fish. Among 37 species, primary freshwater and seawater fish were 8 species (21.6%), respectively and peripheral freshwater fish were 21 species (56.8%). Total biomass of collected fish was 279.3kg, and biomass of each species was T. hakonensis 152.9 kg, H. nipponensis 40.0 kg, K. punctatus 31.4 kg and C. haematochelius 25.3 kg, respectively. Hence, productivity of the Lagoon Hwajinpo was much higher than those of inland reservoirs. The aspect of community classified by surveyed period was changed according to the 'Breaking-sandbar', but some of peripheral freshwater fish populations made stable community in their life cycle in the lagoon. In conclusion, the Lagoon Hwajinpo seems to be maintained more natural ecosystem better than other lagoons in Korea. Therefore, the findings provide consideration of the management and restoration for this lagoon and others through the continuous observation and monitoring in future.

A Comparative Experiment on Dimensional Reduction Methods Applicable for Dissimilarity-Based Classifications (비유사도-기반 분류를 위한 차원 축소방법의 비교 실험)

  • Kim, Sang-Woon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.3
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    • pp.59-66
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    • 2016
  • This paper presents an empirical evaluation on dimensionality reduction strategies by which dissimilarity-based classifications (DBC) can be implemented efficiently. In DBC, classification is not based on feature measurements of individual objects (a set of attributes), but rather on a suitable dissimilarity measure among the individual objects (pair-wise object comparisons). One problem of DBC is the high dimensionality of the dissimilarity space when a lots of objects are treated. To address this issue, two kinds of solutions have been proposed in the literature: prototype selection (PS)-based methods and dimension reduction (DR)-based methods. In this paper, instead of utilizing the PS-based or DR-based methods, a way of performing DBC in Eigen spaces (ES) is considered and empirically compared. In ES-based DBC, classifications are performed as follows: first, a set of principal eigenvectors is extracted from the training data set using a principal component analysis; second, an Eigen space is expanded using a subset of the extracted and selected Eigen vectors; third, after measuring distances among the projected objects in the Eigen space using $l_p$-norms as the dissimilarity, classification is performed. The experimental results, which are obtained using the nearest neighbor rule with artificial and real-life benchmark data sets, demonstrate that when the dimensionality of the Eigen spaces has been selected appropriately, compared to the PS-based and DR-based methods, the performance of the ES-based DBC can be improved in terms of the classification accuracy.

A New Red Color Rose Cultivar "Red Charm" with Few Prickles and Resistance to Powdery Mildew (흰가루병 저항성 및 가시가 적은 적색 장미 신품종 "레드참")

  • Gi, Gwang-Yeon;Hwang, In-Taek;Cho, Kyung-Chul;Lee, Ya-Song;Na, Taek-Sang;Yun, Bong-Ki;Kim, Jung-Guen;Lee, Jae-Sin;Han, Tae-Ho
    • Korean Journal of Breeding Science
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    • v.41 no.4
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    • pp.616-619
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    • 2009
  • A new standard rose cultivar "Red Charm" was bred from the cross between deep red standard cultivar "First Red" and light red standard cultivar "Cardinal" at the Jeollanamdo Agricultural Research and Extention Services (JARES). The cross was made in 2003 and, "Red Charm" was finally selected in 2008 after investigating characteristics for three times from 2007 to 2008. "Red Charm", a red standard cultivar has good flower shape and velvet flower color. The major characteristics of this cultivar are on average $119.3stems/m^2/year$ in yield, 69.5 cm in length of cut flower, 10.3 cm in flower diameter, 36.9 in petal number, and 9.8 days in vase life. This cultivar can be propagated by both cutting and grafting. The consumer's preference of this cultivar, "Red Charm" is relatively higher than that of control cultivar, "Red Velvet".

A New Poinsettia 'Red Stone' with Excellent Branching Ability (분지력이 우수한 적색 포인세티아 'Red Stone' 육성)

  • Lee, Eun-Kyung;Kim, Won-Hee;Kim, Seung-Tae;Lee, Kwang-Seek;Lee, Su-Young
    • Korean Journal of Breeding Science
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    • v.43 no.6
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    • pp.591-594
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    • 2011
  • A new poinsettia(Euphorbia pulcherrima. Willd. ex Klotzch) cultivar 'Red Stone' was bred by the National Institute of Horticultural and Herbal Science (NIHHS) in 2009. In 2006, a cross was made between 'Freedom Rose', a cultivar with vigorous growth and deep pink bracts, and 'Enduring Pink', a cultivar with pink bracts early colored. 'Red Stone' was finally selected in 2009 after the investigation of the growth and flowering characteristics from 2007 to 2009. 'Red Stone' has red elliptic bracts and strong rugosities between bract veins. Leaf blade is ovate and very dark green. Stem color is reddish and petiole length is medium but relatively longer than that of 'Pepride Red', control cultivar. 'Red Stone' develops as many as 3.8 branches and which is more than double of 'Pepride Red'. Its bracts and transitional leaves are fully colored at 7.5 weeks after short-day commencement. Plant variety protection right of 'Red Stone' was registered in April 2011, and its grant number is 3487.