개발산출물의 신뢰성 측정을 위한 메트릭스의 제안과 평가

이하용,황석형,양해술 한국정보처리학회 1998 한국정보처리학회 추계 학술발표논문집 Vol.4 No.1

소프트웨어는 갈수록 대규모화, 다기능화되는 방향으로 발전하고 있다. 더불어 소프트웨어에 관한 사용자의 요구 수준도 높아지고 있으며 특히 소프트웨어의 품질에 대한 요구는 지속적으로 높아지고 있다. 이러한 사용자의 요구를 만족시킬 수 있는 방안들이 다양한 관점에서 연구되고 있다. 그중에서도 소프트웨어의 품질평가를 통해 그 결과를 개발자에게 피드백함으로써 소프트웨어의 품질을 향상시키려는 관점에서 품질평가 체계 및 방법론에 대한 연구가 활발히 진행되고 있다. 본 논문에서는 소프트웨어의 품질에 관한 국제표준인 ISO/IEC 9126의 품질특성 중 신뢰성에 대한 품질특성, 부특성, 내부특성의 체계에 따른 메트릭스와 품질측정표를 개발함으로써 관련 내부특성의 품질평가를 통해 신뢰성에 대한 평가 결과를 산출할 수 있는 체계를 확립하고 개발산출물에 대해 평가한 결과를 제시하였다. α,ω-Bis[Co₂(CO)6{μ-η²:η²-C(R)≡C}]oligothiophene derivatives (6-10), in which two dicobalt hexacarbonyl acetylides are π-conjugated onto both terminals of the oligothiophene, were prepared by the reaction of the α,ω-bis(alkynyl)oligothiophenes (1-5) with Co₂(CO)8. The molecular structures of new compounds were identified by spectroscopic methods and elemental analysis. In cyclic voltammetry of the clusters 6-10, two oligothiophene-based oxidation processes (one for 7) occur between - 0.2 and 1.5 V, and the one reductive process of the metal cluster moieties occurs between 0.0 and - 1.6 V, which is not present for the oligothiophenes (1-5). The silence of the expected electronic communication of the clusters 6-10 may be attributed to the reduction process followed by fast chemical reactions at ambient temperature. The clusters 6-10 commonly exhibit three characteristic bands: a moderately intense, high-energy band, strong medium-energy band and weak-low energy band. The high-energy bands are attributed to the a π-π localized excitation. The medium- and low-energy bands may be ascribed to the metal-to-ligand (d□-π□) charge-transfer transitions of the cluster moiety.

A medium-maturing, disease resistant and good-quality rice variety Geumanbyeo

Hung-goo Hwang,Yeon-gyu Kim,Ha-cheol Hong,Yong-hwan Choi,Man-kee Baek,Im-soo Choi,Young-chan Cho,Chang-in Yang,Hong-yeol Kim,Jong-doo Yea,Young-seop Shin,Kyung-ho Kang,Sang-nag Ahn 한국육종학회 2007 한국육종학회지 Vol.39 No.4

“Geumanbyeo” is a new japonica rice variety developed by the rice breeding team of National Institute of Crop Science, RDA in 2002, which was derived from a cross between SR11878-14-4-1 of good eating-quality and high yield potential, and Suweon345 of lodging tolerance and resistance to diseases. Geumanbyeo is a medium-maturing variety with heading date of August 12 on ordinary planting in the middle plain area. It has a semi-erect plant type with culm length of 82cm, erect pubescent leaf blade and slightly tough culm with good canopy architecture. Geumanbyeo has a little bit fewer tillers per hill, and more spikelets per panicle than Hwaseongbyeo. It is slightly less tolerant to the cold stress in terms of both heading delay and spikelet fertility than Hwaseongbyeo. This variety shows delayed leaf senescence and considerable tolerance to viviparous germination at ripening stage. It shows moderately resistant to leaf blast and K1 race of bacterial blight, but susceptible to virus diseases and insect pests. The milled rice of Geumanbyeo exhibits translucent, relatively clear non-glutinous endosperm and medium-short grain. It showed lower amylose content of 18.6% and similar gelatinization temperature and better palatability of cooked rice compared to Hwaseongbyeo. The milled rice yield of this variety is about 5.32 MT/ha at ordinary culture in local adaptability test for three years. Geumanbyeo would be highly adaptable to the central lowland and mid-southern mountainous areas in Korea. “Geumanbyeo” is a new japonica rice variety developed by the rice breeding team of National Institute of Crop Science, RDA in 2002, which was derived from a cross between SR11878-14-4-1 of good eating-quality and high yield potential, and Suweon345 of lodging tolerance and resistance to diseases. Geumanbyeo is a medium-maturing variety with heading date of August 12 on ordinary planting in the middle plain area. It has a semi-erect plant type with culm length of 82cm, erect pubescent leaf blade and slightly tough culm with good canopy architecture. Geumanbyeo has a little bit fewer tillers per hill, and more spikelets per panicle than Hwaseongbyeo. It is slightly less tolerant to the cold stress in terms of both heading delay and spikelet fertility than Hwaseongbyeo. This variety shows delayed leaf senescence and considerable tolerance to viviparous germination at ripening stage. It shows moderately resistant to leaf blast and K1 race of bacterial blight, but susceptible to virus diseases and insect pests. The milled rice of Geumanbyeo exhibits translucent, relatively clear non-glutinous endosperm and medium-short grain. It showed lower amylose content of 18.6% and similar gelatinization temperature and better palatability of cooked rice compared to Hwaseongbyeo. The milled rice yield of this variety is about 5.32 MT/ha at ordinary culture in local adaptability test for three years. Geumanbyeo would be highly adaptable to the central lowland and mid-southern mountainous areas in Korea.

Cytotoxic Effects of Sesquiterpene Lactones from the Flowers of Hemisteptia Iyrata B.

Ha, Tae-Joung,Jang, Dae-Sik,Lee, Jong-Rok,Lee, Kyung-Dong,Lee, Jun,Hwang, Seon-Woo,Jung, Hwa-Jin,Nam, Sang-Hae,Park, Ki-Hun,Yang, Min-Suk The Pharmaceutical Society of Korea 2003 Archives of Pharmacal Research Vol.26 No.11

Four guaia-12,6-olide type sesquiterpene lactones, aguerin B (1), 8$\alpha$-acetoxyzaluzanin C (2), cynaropicrin (3), and deacylcynaropicrin (4), were isolated from the flowers of Hemisteptia Iyrata Bunge. It is the first report on the isolation of compounds 1-4 from Hemisteptia species. All the isolates (1-4) were examined for their cytotoxic activity against SK-OV-3, LOX-IMVI, A549, MCF-7, PC-3, and HCT-15 human cancer cell lines.

Artificial cellular nano-environment composed of collagen-based nanofilm promotes osteogenic differentiation of mesenchymal stem cells

Hwang, Jun-Ha,Han, Uiyoung,Yang, Miso,Choi, Yonghyun,Choi, Jonghoon,Lee, Jong-Min,Jung, Han-Sung,Hong, Jinkee,Hong, Jeong-Ho Elsevier 2019 ACTA BIOMATERIALIA Vol.86 No.-

<P><B>Abstract</B></P> <P>In regenerative medicine, the generation of therapeutic stem cells and tissue engineering are important for replacing damaged tissues. Numerous studies have attempted to produce cellular components that mimic the native tissue for gaining optimal function. Particularly, the extracellular matrix (ECM) composition plays an important role in cellular functions including determining the fates of mesenchymal stem cells (MSCs). Here, we evaluated the osteogenic effects of a nanofilm in which oppositely charged polyelectrolytes were alternately adsorbed onto the cell surface to create an artificial ECM environment for single MSCs. Interestingly, nanofilm composed of collagen (Col) and alginate (AA) showed relatively high stiffness and MSCs coated with the Col/AA nanofilm showed increased osteogenic differentiation efficiency compared to other nanofilm-coated MSCs. Further analysis revealed that the Col/AA nanofilm coating stimulated osteogenesis by activating transcriptional coactivators with the PDZ binding motif through extracellular signal-related kinase and p38 MAPK signaling. This nano-sized cellular coating will facilitate the development of nanotechnology for controlling cellular functions and advance stem cell-based clinical applications for regenerative medicine.</P> <P><B>State of Significance</B></P> <P>In this study, we developed an artificial cellular nano-environment formed by multilayer nanofilms. We demonstrated that the nanofilms introduced to mesenchymal stem cells (MSCs) stimulate osteogenic differentiation by regulating intracellular signaling. Among the various nanofilm combinations, the induction of osteogenic gene transcription in collagen (Col) and alginate (AA) film-coated MSCs was the most pronounced compared to that on other nanofilms. A minimum number of Col/AA nanofilm bilayers (n = 2) was required for effective induction of MSC osteogenic differentiation. In addition, we observed the correlation between the promoting effect of osteogenic differentiation and stiffness of the nanofilm. Our results may be useful for developing a cell coating model system widely applicable in bioengineering and regenerative medicine.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

<i>In Vitro</i> and <i>In Vivo</i> Genotoxicity Assessment of <i>Aristolochia manshuriensis</i> Kom.

Hwang, Youn-Hwan,Kim, Taesoo,Cho, Won-Kyung,Yang, Hye Jin,Kwak, Dong Hoon,Ha, Hyunil,Song, Kwang Hoon,Ma, Jin Yeul Hindawi Publishing Corporation 2012 Evidence-based Complementary and Alternative Medic Vol.2012 No.-

<P><I>Arisolochiae species </I>plants containing aristolochic acids I and II (AA I and AA II) are well known to cause aristolochic acid nephropathy (AAN). Recently, there are various approaches to use AAs-containing herbs after the removal of their toxic factors. However, there is little information about genotoxicity of <I>Arisolochiae manshuriensis</I> Kom. (AMK) <I>per se</I>. To obtain safety information for AMK, its genotoxicity was evaluated in accordance with OECD guideline. To evaluate genotoxicity of AMK, we tested bacterial reverse mutation assay, chromosomal aberration test, and micronucleus test. Here, we also determined the amounts of AA I and II in AMK (2.85 ± 0.08 and 0.50 ± 0.02 mg/g extract, resp.). In bacterial reverse mutation assay, AMK dose-dependently increased revertant colony numbers in TA98, TA100 and TA1537 regardless of metabolic activation. AMK increased the incidence of chromosomal aberration in Chinese hamster ovary-K1 cells, but there was no statistically significant difference. The incidences of micronucleus in bone marrow erythrocyte were significantly increased in mice after oral administration of AMK (5000 mg/kg), comparing with those of vehicle group (<I>P</I> < 0.05). The results of three standard tests suggest that the genotoxicity of AMK is directly related to the AAs contents in AMK.</P>

New Selection Criterion for a Base Polar Liquid in the Lifshitz–van der Waals/Lewis Acid–Base Approach

Hwang, Geelsu,Yang, Ji-hyun,Lee, Chang-Ha,Ahn, Ik-Sung,Mhin, Byung Jin American Chemical Society 2011 The Journal of Physical Chemistry Part C Vol.115 No.25

<P>To understand the adhesion of a colloid or a microbe to a solid surface in terms of thermodynamics, the interfacial energy should be calculated with the respective surface tensions. The Lifshitz–van der Waals/Lewis acid–base (LW-AB) approach is most widely used for the evaluation of these surface tension components and requires contact angles of the solid with an apolar liquid, water, and one base polar liquid. Holländer’s criterion has been suggested for the selection of the base polar liquid regardless of the nature of the solid. However, large deviations in the AB surface tension components of the solid (γ<sub arrange='stack'>s</SUB><sup arrange='stack'>+</SUP> and γ<sub arrange='stack'>s</SUB><sup arrange='stack'><I>–</I></SUP>), especially γ<sub arrange='stack'>s</SUB><sup arrange='stack'>+</SUP>, and the positive AB component of the interfacial energy (Δ<I>G</I><sub arrange='stack'>sl</SUB><sup arrange='stack'>AB</SUP>) have often been found depending on the nature of the polar liquid. In this study, the following selection criterion for the base polar liquid has been derived from a mathematical analysis of the LW-AB approach: 0 > (γ<sub arrange='stack'>p</SUB><sup arrange='stack'>+</SUP>)<SUP>1/2</SUP>/(γ<sub arrange='stack'>w</SUB><sup arrange='stack'>+</SUP>)<SUP>1/2</SUP>Δ<I>G</I><sub arrange='stack'>sw</SUB><sup arrange='stack'>AB</SUP> > Δ<I>G</I><sub arrange='stack'>sp</SUB><sup arrange='stack'>AB</SUP> > (γ<sub arrange='stack'>p</SUB><sup arrange='stack'>+</SUP>)<SUP>1/2</SUP>/(γ<sub arrange='stack'>w</SUB><sup arrange='stack'>+</SUP>)<SUP>1/2</SUP> Δ<I>G</I><sub arrange='stack'>sw</SUB><sup arrange='stack'>AB</SUP>[(γ<sub arrange='stack'>p</SUB><sup arrange='stack'>–</SUP>/γ<sub arrange='stack'>p</SUB><sup arrange='stack'>+</SUP>)<SUP>1/2</SUP> – (γ<sub arrange='stack'>w</SUB><sup arrange='stack'>–</SUP>/γ<sub arrange='stack'>w</SUB><sup arrange='stack'>+</SUP>)<SUP>1/2</SUP> + 1] (s = solid; w = water; and p = the base polar liquid). Using four model solids, this criterion has been evaluated for the selection of the base polar liquid among glycerol, formamide, and ethylene glycol. Reliable surface tension components of the solid were obtained when the above criterion was satisfied. When γ<sub arrange='stack'>w</SUB><sup arrange='stack'>+</SUP> and γ<sub arrange='stack'>w</SUB><sup arrange='stack'>–</SUP> are set to be identical, the above criterion is then <I>Q</I><SUB>γ</SUB> > [(Δ<I>G</I><sub arrange='stack'>sw</SUB><sup arrange='stack'>AB</SUP>(γ<sub arrange='stack'>p</SUB><sup arrange='stack'>–</SUP>)<SUP>1/2</SUP>)/(Δ<I>G</I><sub arrange='stack'>sp</SUB><sup arrange='stack'>AB</SUP>(γ<sub arrange='stack'>w</SUB><sup arrange='stack'>–</SUP>)<SUP>1/2</SUP>)]<SUP>2</SUP> > 1, which is believed to be a detailed version of Holländer’s criterion.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2011/jpccck.2011.115.issue-25/jp200741v/production/images/medium/jp-2011-00741v_0001.gif'></P>

Trapping of Microparticles in Cylindrical Standing Wave Fields

Yang, Jeongwon,Hwang, Haerang,Bae, Young Min,Kim, Moojoon,Ha, Kanglyeol IOP Publishing 2013 Japanese journal of applied physics Vol.52 No.7

<P>In this study, in order to determine the positions where microparticles are trapped in a cylindrical standing wave field, we derived equations giving the radiation force and potential energy distribution. Then, the trapped pattern and its variation with time in a hollow cylindrical transducer were simulated. The simulation results showed that polystyrene particles moved to and aggregated near positions corresponding to pressure nodes, which were estimated from the derived equations. These were confirmed by measurement. In addition, it was demonstrated that biological particles of the green algae chlorella show similar trapping phenomena to polystyrene particles. (c) 2013 The Japan Society of Applied Physics</P>

Genome-wide analysis of mutations in a dwarf soybean mutant induced by fast neutron bombardment

Hwang, Won Joo,Kim, Moon Young,Kang, Yang Jae,Shim, Sangrea,Stacey, Minviluz G.,Stacey, Gary,Lee, Suk-Ha Springer-Verlag 2015 Euphytica Vol.203 No.2

Large-area epitaxial CdTe(100) films grown on GaAs(100) substrates: MBE growth and substrate temperature effect

Hwang Younghun,Ngugen Van Quang,Choi Jin San,Park Sujung,Cho Shinuk,Kim Tae Heon,Ha Yang,Ahn Chang Won 한국물리학회 2021 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.79 No.11

The epitaxial growth of high-quality thin films provides a powerful method for the rapid preparation of new materials and discovery of materials with promising properties. Here, we report the effect of substrate temperature on the epitaxial growth of high-quality and large-area epitaxial CdTe films on GaAs(100) by molecular beam epitaxy. RHEED patterns as a function of the substrate temperature showed sharp streaky lines. A CdTe epilayer grown at 320 °C showed the narrowest full-width at half-maximum (FWHM) of 180 arcsec from (004) reflection in X-ray rocking curve measurements. The smooth and flat surface observed in the AFM image showed the excellent uniformity of the thin film, and the surface roughness decreased monotonically with the substrate temperature. From the substrate temperature dependence of the ( A0, X) emission line, the luminescence intensity was found to increase with increasing substrate temperature, while the FWHM decreased with substrate temperature. Our experimental data suggest that the substrate temperature plays an important role in establishing hetero-epitaxial film growth for semiconductor devices.

Membrane-reinforced three-dimensional electrospun silk fibroin scaffolds for bone tissue engineering

Yang, Sung Yeun,Hwang, Tae Heon,Che, Lihua,Oh, Jin Soo,Ha, Yoon,Ryu, WonHyoung Institute of Physics Publishing Ltd 2015 Biomedical Materials Vol.10 No.3

<P>Electrospun silk fibroin (SF) scaffolds have drawn much attention because of their resemblance to natural tissue architecture such as extracellular matrix, and the biocompatibility of SF as a candidate material to replace collagen. However, electrospun scaffolds lack the physical integrity of bone tissue scaffolds, which require resistance to mechanical loadings. In this work, we propose membrane-reinforced electrospun SF scaffolds by a serial process of electrospinning and freeze-drying of SF solutions in two different solvents: formic acid and water, respectively. After wet electrospinning followed by replacement of methanol with water, SF nanofibers dispersed in water were mixed with aqueous SF solution. Freeze-drying of the mixed solution resulted in 3D membrane-connected SF nanofibrous scaffolds (SF scaffolds) with a thickness of a few centimeters. We demonstrated that the SF concentration of aqueous SF solution controlled the degree of membrane reinforcement between nanofibers. It was also shown that both increase in degree of membrane reinforcement and inclusion of hydroxyapatite (HAP) nanoparticles resulted in higher resistance to compressive loadings of the SF scaffolds. Culture of human osteoblasts on collagen, SF, and SF-HAP scaffolds showed that both SF and SF-HAP scaffolds had biocompatibility and cell proliferation superior to that of the collagen scaffolds. SF-HAP scaffolds with and without BMP-2 were used for in vivo studies for 4 and 8?weeks, and they showed enhanced bone tissue formation in rat calvarial defect models.</P>