Advanced H2O2 oxidation for diethyl phthalate degradation in treated effluents: effect of nitrate on oxidation and a pilot-scale AOP operation

Ko, K. B.,Park, C. G.,Moon, T. H.,Ahn, Y. H.,Lee, J. K.,Ahn, K. H.,Park, J. H.,Yeom, I. T. IWA Publishing 2008 Water Science & Technology Vol.58 No.5

<P>One of the objectives of this study was to delineate the effect of nitrate on diethyl phthalate (DEP) oxidation by conducting a bench-scale ultraviolet (UV)/H2O2 and O3/H2O2 operations as suggested in a previous study. We also aim to investigate DEP oxidation at various UV doses and H2O2 concentrations by performing a pilot-scale advanced oxidation processes (AOP) system, into which a portion of the effluent from a pilot-scale membrane bioreactor (MBR) plant was pumped. In the bench-scale AOP operation, the O3 oxidation alone as well as the UV irradiation without H2O2 addition could be among the desirable alternatives for the efficient removal of DEP dissolved in aqueous solutions at a low DEP concentration range of 85±15 μg/L. The adverse effect in the UV/H2O2 process was significantly greater than that in the UV oxidation alone, and its oxidation was almost halved by the nitrate. However, the nitrate clearly enhanced the DEP oxidation in the O3 oxidation and O3/H2O2 process. Especially, the addition of nitrate almost doubled the DEP oxidation efficiency in the O3/H2O2 process. The series of pilot-scale AOP operations confirmed that about 30-50% of DEP dissolved in the treated MBR effluent streams was, at least, oxidized by the O3 oxidation alone as well as the UV irradiation without H2O2 addition. The UV photolysis of H2O2 was most effective for DEP degradation with an H2O2 concentration of 40 mg/L at a UV dose of 500 mJ/cm2.</P>

Fermentation for Liquid-type Yogurt with Lactobacillus casei 911LC

Ko, I.H.,Wang, M.K.,Jeon, B.J.,Kwak, H.S. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.1

This study was carried out to find the attributes for liquid-type yogurt with Lactobacillus casei 911LC during 72 h fermentation at $37^{\circ}C$. The pH decreased up to 32 h and plauteaued thereafter, and the titratable acidity increased up to 40 h. The growth of lactic acid bacteria sharply increased with $3.5{\times}10^7$ cfu/ml up to 40 h of fermentation and slowly decreased thereafter. The free amino acids produced during fermentation reached the maximum value at 44 h and gradually decreased thereafter. Bitterness sensory scores were the highest at 44 h of fermentation. In the result of electrophoresis, the band mostly disappeared at 72 h fermentation. The present data showed that the range of optimum fermentation time for liquid-type yogurt using Lactobacillus casei 911LC was from 40 to 44 h.

플랜지가 있는 제품에서 부분패드의 영향에 관한 연구

고관영,허주환,문정효,장재석,김동윤,정민섭,김주찬,박기용,이강연,조명우,이권진,조영호,이효걸,김주호,이경희 울산과학대학 2000 연구논문집 Vol.27 No.1

본 논문에서는 기존의 Motion-JPEG 기반 감시시스템에서 낮은 동영상 압축성능 문제를 해결하기 위한 새로운 동영상 압축기법을 제안하였다. 제안된 방법에서는 현재 프레임의 JPEG 데이터 중 변화된 압축 데이터만이 실시간으로 추출하고 저장된다. 제안된 방법에 의해 저장된 데이터는 기존의 JPEG과는 다른 고유의 포맷을 가지기 때문에, 동영상 데이터는 더욱 안전하게 유지될 수 있다. 실험을 통해, 제안된 동영상 압축기법의 압축률이 기존의 Motion-JPEG 기반 감시시스템에 비해 3배정도 높다는 것을 확인할 수 있었다.

Overview of KSTAR research progress and future plans toward ITER and K-DEMO

Park, H.K.,Choi, M.J.,Hong, S.H.,In, Y.,Jeon, Y.M.,Ko, J.S.,Ko, W.H.,Kwak, J.G.,Kwon, J.M.,Lee, J.,Lee, J.H.,Lee, W.,Nam, Y.B.,Oh, Y.K.,Park, B.H.,Park, J.K.,Park, Y.S.,Wang, S.J.,Yoo, M.,Yoon, S.W.,B IOP 2019 Nuclear fusion Vol.59 No.11

<P>A decade-long operation of the Korean Superconducting Tokamak Advanced Research (KSTAR) has contributed significantly to the operation of superconducting tokamak devices and the advancement of tokamak physics which will be beneficial for the ITER and K-DEMO programs. Even with limited heating capability, various conventional as well as new operating regimes have been explored and have achieved improved performance. As examples, a long pulse high-confinement mode operation with and without an edge-localized mode (ELM) crash was well over 70 and 30 s, respectively. The unique capabilities of KSTAR allowed it to improve the capability of controlling harmful instabilities, and they have been instrumental in uncovering much new physics. The highlights are that the L/H transition threshold power is sensitive to the resonant magnetic perturbation (RMP) and insensitive to non-resonant magnetic perturbation. Co-<I>I</I> <SUB>p</SUB> offset rotation dominated by an electron channel predicted by general neoclassical toroidal viscosity theory was confirmed. Improved heat dispersal in a divertor system using three rows of rotating RMP was demonstrated and predictive control of the ELM-crash with <I>a priori</I> modeling was successfully tested. In magnetohydrodynamic physics, validation of the full reconnection model (i.e. <I>q</I> <SUB>0</SUB>  >  1 right after the sawtooth crash) and self-consistent validation of the anisotropic distribution of turbulence amplitude and flow in the presence of the 2/1 island with theoretical models were achieved. The turbulence amplitude induced by RMP was linearly increased with the slow RMP coil current ramp-up time (i.e. the magnetic diffusion time scale). The <I>D</I> <SUB> <I>α</I> </SUB> spikes (i.e. ELM-crash amplitude) was linearly decreased with the turbulence amplitude and not correlated with the perpendicular electron flow. In the turbulence area, a non-diffusive ‘avalanche’ transport event and the role of a quiescent coherent mode in confinement were studied. To accommodate the anticipation of a higher performance of the KSTAR plasmas with the increased heating powers, a new divertor/internal interface with a full active cooling system will be implemented after a full test of the new heating (neutral beam injection II and electron cyclotron heating) and current drive (CD) (Helicon and lower hybrid CD) systems. An upgrade plan for the internal hardware, heating systems and efficient CD system may allow for a long pulse operation of higher performance plasmas at <I>β</I> <SUB>N</SUB>  >  3.0 with <I>f</I> <SUB>bs</SUB> ~ 0.5 and <I>T</I> <SUB>i</SUB>  >  10 keV.</P>

Emergence of an extended-spectrum <i>β</i>-lactamase-producing serotype K1 <i>Klebsiella pneumoniae</i> ST23 strain from Asian countries

CHEONG, H. S.,CHUNG, D. R.,PARK, M.,KIM, S. H.,KO, K. S.,HA, Y. E.,KANG, C. I.,PECK, K. R.,SONG, J. H. Cambridge University Press 2017 Epidemiology and infection Vol.145 No.5

<B>SUMMARY</B><P>Extended-spectrum <I>β</I>-lactamase (ESBL) production has been very rare in serotype K1 <I>Klebsiella pneumoniae</I> ST23 strains, which are well-known invasive community strains. Among 92 ESBL-producing strains identified in 218 isolates from nine Asian countries, serotype K1 <I>K. pneumoniae</I> strains were screened. Two ESBL-producing <I>K. pneumoniae</I> isolates from Singapore and Indonesia were determined to be serotype K1 and ST23. Their plasmids, which contain CTX-M-15 genes, are transferable rendering the effective transfer of ESBL resistance plasmids to other organisms.</P>

Effects of HA and NA glycosylation pattern changes on the transmission of avian influenza A(H7N9) virus in guinea pigs

Park, S.,Lee, I.,Kim, J.I.,Bae, J.Y.,Yoo, K.,Kim, J.,Nam, M.,Park, M.,Yun, S.H.,Cho, W.I.,Kim, Y.S.,Ko, Y.Y.,Park, M.S. Academic Press 2016 Biochemical and biophysical research communication Vol.479 No.2

Avian influenza H7N9 virus has posed a concern of potential human-to-human transmission by resulting in seasonal virus-like human infection cases. To address the issue of sustained human infection with the H7N9 virus, here we investigated the effects of hemagglutinin (HA) and neuraminidase (NA) N-linked glycosylation (NLG) patterns on influenza virus transmission in a guinea pig model. Based on the NLG signatures identified in the HA and NA genetic sequences of H7N9 viruses, we generated NLG mutant viruses using either HA or NA gene of a H7N9 virus, A/Anhui/0½013, by reverse genetics on the 2009 pandemic H1N1 virus backbone. For the H7 HA NLG mutant viruses, NLG pattern changes appeared to reduce viral transmissibility in guinea pigs. Intriguingly, however, the NLG changes in the N9 NA protein, such as a removal from residue 42 or 66 or an addition at residue 266, increased transmissibility of the mutant viruses by more than 33%, 50%, and 16%, respectively, compared with a parental N9 virus. Given the effects of HA-NA NLG changes with regard to viral transmission, we then generated the HA-NA NLG mutant viruses harboring the H7 HA of double NLG addition and the N9 NA of various NLG patterns. As seen in the HA NLG mutants above, the double NLG-added H7 HA decreased viral transmissibility. However, when the NA NLG changes occurred by a removal of residue 66 and an addition at 266 were additionally accompanied, the HA-NA NLG mutant virus recovered the transmissibility of its parental virus. These demonstrate the effects of specific HA-NA NLG changes on the H7N9 virus transmission by highlighting the importance of a HA-NA functional balance.

Scalable CGeSbTe-based phase change memory devices employing U-shaped cells

Park, J.H.,Kim, J.H.,Ko, D.-H.,Wu, Z.,Ahn, D.H.,Park, S.O.,Hwang, K.H. Elsevier S.A. 2017 Thin Solid Films Vol.634 No.-

<P><B>Abstract</B></P> <P>Phase change memory (PCM) that is operated on resistance changes caused by joule heating has been suggested as the next-generation memory for scaling since its programming current scales linearly. We propose a U-shaped cell design to further reduce the reset current in PCM devices, which enables easier and more efficient scaling than conventional PCMs. Simulation studies of heat transfer demonstrated that our U-shaped design with a dashed heater has a higher thermal efficiency of 4.97K/μA compared to 3.36K/μA in a lance cell with a ring heater for the same storage node. The reset current can be better scaled proportionate to k<SUP>2.0</SUP> in which the exponent is higher than the lance cell of k<SUP>1.5</SUP> in non-isotropic scaling. This better scalability is attributed to the small programming volume of the U-shaped cell, which was verified by transmission electron microscopy analysis. Furthermore, the cyclic endurance of the U-shaped cell was enhanced by 1 order of magnitude compared to a lance cell and the thinner CGeSbTe films reduced the reset current further. Our results show that a U-shaped cell is a highly promising design to scale reset current in next-generation PCM devices.</P> <P><B>Highlights</B></P> <P> <UL> <LI> U-shaped cell is a promising cell design to scale phase change memory. </LI> <LI> U-shaped cell with dashed heater is more thermally efficient than lance cell with ring heater. </LI> <LI> Thinner CGeSbTe layer can reduce the reset current further. </LI> </UL> </P>

In vitro Fertilization and Development of Pig Oocytes Inseminated with Boar Sperm by Different Sperm Washing Media after Thawing of the Frozen Straws

Yi, Y.J.,Ko, H.J.,Lee, S.H.,Yang, C.B.,Son, D.S.,Kim, H.K.,Park, C.S. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.2

This study was carried out to investigate in vitro fertilization and development of in vitro matured pig oocytes inseminated with the Duroc boar sperm by different sperm washing media after thawing of the 5 ml frozen straws. Immature follicular oocytes (30-40) were transferred into each well of a Nunc 4-well multidish containing $500{\mu}l$ mTCM199 maturation medium. The sperm rich portion of ejaculates was collected into a 250 ml insulated vacuum bottle and gradually cooled 22 to $24^{\circ}C$ over a 2 h period. Semen was centrifuged at 800 g for 10 min and the seminal plasma discarded. Sperm were esuspended in a lactose-egg yolk and N-acetyl-Dglucosamine (LEN) diluent to contain $1{\times}10^{9}$ sperm/ml and cooled to $5^{\circ}C$ over a 2 h period. Immediately before freezing, semen was rediluted with an equal volume of LEN+4% glycerol and packed into 5 ml straws. After thawing of the 5 ml straw, the 5 ml semen was diluted with 20 ml Beltsville thawing solution (BTS) at room temperature. Oocytes were inseminated with untreated (unwashed and nonpreincubated) or treated sperm (washed two times in BTS, mTLP-PVA and mTBM media, respectively and nonpreincubated) with $2{\times}10^{7}$ sperm concentration. Oocytes were coincubated for 6 h in $500{\mu}l$ mTBM fertilization. At 6 h after IVF, oocytes were transferred into $500{\mu}l$ NCSU-23 culture medium for further culture of 6 h. Sperm penetration, polyspermy and male pronuclear formation of oocytes at 12 h after IVF and developmental ability of oocytes at 48 h after IVF were evaluated. Sperm penetration rate, male pronuclear formation and rate of cleaved embryos were higher in the BTS, mTLP-PVA and mTBM treatments than the unwashed treatment (p<0.05). The rate of blastocysts from the cleaved oocytes (2-4 cell stage) were higher in the mTLP-PVA treatment than in the unwashed, BTS and mTBM treatments. In conclusion, we recommend the washing of frozen-thawed sperm with mTLP-PVA medium before in vitro fertilization of oocytes in mTBM medium.

Search for lepton flavor and lepton number violating <i>τ</i> decays into a lepton and two charged mesons

Miyazaki, Y.,Aihara, H.,Arinstein, K.,Aulchenko, V.,Aushev, T.,Bakich, A.M.,Balagura, V.,Barberio, E.,Bay, A.,Belous, K.,Bhardwaj, V.,Bischofberger, M.,Bondar, A.,Brač,ko, M.,Browder, T.E.,Chang, North-Holland Pub. Co 2010 Physics letters. Section B Vol.682 No.4

<P><B>Abstract</B></P><P>We search for lepton flavor and lepton number violating <I>τ</I> decays into a lepton (ℓ=electron or muon) and two charged mesons (h,<SUP>h′</SUP>=<SUP>π±</SUP> or <SUP>K±</SUP>), <SUP>τ−</SUP>→<SUP>ℓ−</SUP><SUP>h+</SUP><SUP>h′−</SUP> and <SUP>τ−</SUP>→<SUP>ℓ+</SUP><SUP>h−</SUP><SUP>h′−</SUP>, using 671 fb<SUP>−1</SUP> of data collected with the Belle detector at the KEKB asymmetric-energy <SUP>e+</SUP><SUP>e−</SUP> collider. We obtain 90% C.L. upper limits on the branching fractions in the range (4.4–8.8)×<SUP>10−8</SUP> for τ→eh<SUP>h′</SUP>, and (3.3–16)×<SUP>10−8</SUP> for τ→μh<SUP>h′</SUP> processes. These results improve upon previously published upper limits by factors between 1.6 to 8.8.</P>

Search for the H Dibaryon in (K-, K+) Reactions

Bahk,S. Y.,Chung,K. S,Chung,S. H.,Funahashi,H.,Hahn,C. H.,Hara,T.,Hirata,S.,Hoshino,K.,Ieiri,M.,Iijima,T.,Imai,K.,Ishigami,T.,Itow,Y.,Kazuno,M.,Kikuchi,K.,Kim,C. O.,Kim,D. C.,Kim,J. Y.,Kobayashi,M.,Ko 國立昌原大學校 基礎科學硏究所 1992 基礎科學硏究所論文集 Vol.3 No.-

We have studied(??) reactions from an emulsion target. The S--2H dibaryon has been searched for by the analysis of the ??? momentum spectrum together with emulsion data. No evidence of H production was observed in the mass range of 1.90-2.16 GeV/c². Upper limits for the production cross section of the H are (0.2-0.6)% of that for the quasifree ??? production at the 90% confidence level.