• Title/Summary/Keyword: L1 influence

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Influence factors and Efficiencies Characteristics for Treatment of Wastewater Containing Phenol (Phenol 함유폐수의 처리를 위한 영향인자와 성능특성)

  • Kang, Sun-Tae;Kim, Jeong-Mog
    • Journal of Korean Society of Water and Wastewater
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    • v.10 no.4
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    • pp.119-126
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    • 1996
  • Influence factors and efficiency characteristics for treatment of wastewater containing phenol were studied with using Pseudomonas sp. B3. It took 130 hours to remove phenol, when only activated sludge of terminal disposal palnt of sewage was innoculated in batch culture, but it was required just 36 hours, when bacteria degrading phenol and activated sludge were simultaneously innoculated. If only phenol an carbon source was used, it necessary 36 hours for biodegradation of phenol, while glucose was added to medium, it took 73 hours. It was revealed as excellent effluent and SVI, when the F/M ratio, COD and phenol concentration were 53mg/l and 1.2mg/l, respectively, and optimum F/M ratio was revealed 0.31. The reactor were seriously shocked as reducing hydraulic retention time at constant phenol concentration more than increasing phenol concentration at constant hydraulic retention time, when volumetric loading rate was increased to $0.8kg\;phenol/m^3{\codt}d$ from $1.6kg\;phenol/m^3{\codt}d$. And also the effluent phenol concentration was 34mg/l after starting 12 hours of shocking and reactor was recovered as steady state after 65 hours of changing in the former test. Although the effluent phenol concentration was maximum value with 12mg/l after starting 20 hours of shocking and reactor was recovered as steady state after 54 hours of changing in the later test.

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Influence of Culture Comditions on Acid Tolerance of Lactobacillus casei YIT 9018 (배양조건에 따른 Lactobacillus casei YIT 9018의 니산성 변화)

  • Sim, Jae-Hun;Kim, Sang-Kyo;Baek, Young-Jin;Oh, Tae-Kwang;Yang, Han-Chul
    • Microbiology and Biotechnology Letters
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    • v.23 no.1
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    • pp.17-23
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    • 1995
  • We studied the influence of culture conditions on the acid tolerance of Lactobacillus casei YIT 9018 in artificial gastric juice with respect to relative amount of membrane bound ATPase and their biochemical characteristics. With raising incubation temperature from 30.5$\circ$C to 40.5$\circ$C and lengthening incubation time from exponential phase to late stationary phase, the acid tolerance of L. casei YIT 9018 was increased. As acid tolerance enhanced, C$_{18:1}$ content of membrane fatty acid was reduced and C$_{19:0 cyclo}$ was enriched but the others were not changed greatly. At high ATPase activity, proton permeability was relatively low but this phenomenon did not correspond to acid tolerance. In conclusion, it was considered that changes of C$_{18:1}$ and C$_{19:0 cyclo}$ were closely related to the acid tolerance of L. casei YIT 9018.

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Probabilistic free vibration analysis of Goland wing

  • Kumar, Sandeep;Onkar, Amit Kumar;Manjuprasad, M.
    • International Journal of Aerospace System Engineering
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    • v.6 no.2
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    • pp.1-10
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    • 2019
  • In this paper, the probabilistic free vibration analysis of a geometrically coupled cantilever wing with uncertain material properties is carried out using stochastic finite element (SFEM) based on first order perturbation technique. Here, both stiffness and damping of the system are considered as random parameters. The bending and torsional rigidities are assumed as spatially varying second order Gaussian random fields and represented by Karhunen Loeve (K-L) expansion. Here, the expected value, standard deviation, and probability distribution of random natural frequencies and damping ratios are computed. The results obtained from the present approach are also compared with Monte Carlo simulations (MCS). The results show that the uncertain bending rigidity has more influence on the damping ratio and frequency of modes 1 and 3 while uncertain torsional rigidity has more influence on the damping ratio and frequency of modes 2 and 3.

The Influence of Velocity and Temperature on Streaming Charging Tendeny of Insulting Oil (절연유의 유속과 유온이 유동대전에 미치는 영향)

  • Kim, Myung-Nyung;Kang, Seong-Hwa;Lim, Kee-Joe;Kang, Dou-Yol;Kim, Bong-Heup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1988.05a
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    • pp.70-73
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    • 1988
  • Influence of Velocity and Temperature on Streaming Electrification of Insulating Oil is investigated by injection method. Leakage current is increased slightly with increasing temperature in the temperature range 20 to $80^{\circ}C$ at low flow rate, however, it show a peak in the temperature 40 to $60^{\circ}C$ at high flow rate. Leakage current is also increased linearly with increasing flow rate in the flow rate range 1 - 31/min but thereafter, it is increased abruptly with increasing flow rate.

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Influence of Elapsed Years and Physical Properties on Vegetation Invasion of Forest Road Slope (임도시공경과년수 및 물리적 특성이 임도사면의 식생 침입에 미치는 영향)

  • Lee, Joon Woo;Choo, Gab-Chul;Choi, Yeon Ho
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.1
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    • pp.28-34
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    • 2002
  • This study was carried out to analyze the effects of elapsed years and physical properties on invaded vegetation of forest road slope. For the study, 8 forest roads in Asan-si of Chungcheongnam-do were selected and 15 factors that might influence on vegetation invasion were analyzed. In generally, vegetation coverage of slope have increased with the elapsed years. But invasion species have decreased in the cut-slope and increased in fill-slope. There was no significant correlation between rate of vegetation coverage and elapsed years, but rate of vegetation coverage was strongly related with slope aspect. And the species of invasion vegetation affected mostly by the elapsed years and slope aspect among the physical properties.

Relative Influence of Sediments, Food and Dissolved Sources on Ag Bioaccumulation in the Amphipod Leptocheirus plumulosus (오염된 퇴적물로부터 해양저서 단각류 Leptocheirus plumulosus의 은(Ag)축적에서 흡수경로의 상대적 기여도 평가)

  • Yoo, Hoon;Lee, In-Tae;Lee, Byeong-Gweon
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.7 no.2
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    • pp.87-93
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    • 2002
  • A amphipod, Leptocheirus plumulosus was exposed to Ag contaminated sediments to evaluate relative importance of various uptake routes (sediment, porewater, supplementary food) for Ag bioaccumulation in sediment-dwelling marine invertebrates. Additionally, influence of AVS (acid-volatile sulfide) on the partitioning of Ag to porewater and on the Ag bioavailability was determined to evaluate the utility of AVS criteria for the management of metal contaminated sediment. The experimental sediments were spiked with 4 levels of Ag (0.1-3.3 ${\mu}$mol Ag/g) and AVS concentrations were manipulated to 40 or <0.5 ${\mu}$mol/g, then equilibrated for >2 months to allow pore water/particulate distributions similar to nature. A L. plumulosus was incubated in the contaminated sediments with overlying water for 35d. During the exposure, the amphipods was fed with supplementary food ($TetraMin^{(R)}$) with or without Ag contamination. Following exposure, tissue Ag in L. plumulosus was strongly correlated with the weak acid extractable Ag in sediments ($r^{2}$=0.87, p<0.001). The ratio of AVS to Ag-SEM (Ag extracted simulaneouls with AVS) had a strong influence on porewater Ag concentration, consistent with previous studies. However, Ag bioaccumulation in L. plumulosus was not influenced by AVS concentrations. The amphipods fed Ag contaminated food took up ${\sim}$ 1.8 X Ag accumulated by the amphipods fed uncontaminated supplementary diet. The result suggests that the benthic invertebrates exposed to metal contaminated sediments would accumulate metals largely via ingestion of contaminated sediments and food, with minor contribution from dissolved sources of porewater and overlying water.

Influence of Hyaluronic Acid on the Different Levels of Lysozyme and Peroxidase in the Aspects of Candidacidal Activities

  • Kim, Jihoon;Kim, Yoon-Young;Chang, Ji-Youn;Kho, Hong-Seop
    • Journal of Oral Medicine and Pain
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    • v.43 no.1
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    • pp.1-7
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    • 2018
  • Purpose: The purpose of the study was to investigate the influences of hyaluronic acid on the candidacidal activities of lysozyme, the peroxidase system, and the glucose oxidase-mediated peroxidase (GO-PO) system at different concentrations of antimicrobial enzymes. Methods: Hyaluronic acid was used at a final concentration of 0.5 mg/mL. Hen egg-white lysozyme (HEWL) was used at concentrations ranging from 10 to $100{\mu}g/mL$. The peroxidase system included bovine lactoperoxidase (bLPO), potassium thiocyanate (KSCN, 1 mM), and hydrogen peroxide ($100{\mu}M$). The GO-PO system included bLPO, KSCN (1 mM), glucose oxidase (10 units/mL), and glucose ($30{\mu}g/mL$). The final concentration of bLPO in the peroxidase and GO-PO systems ranged from 12.5 to $100{\mu}g/mL$. Candida albicans strains ATCC 10231, 11006, and 18804 were utilized. Candidacidal activities of antimicrobials and the influence of hyaluronic acid on their candidacidal activities were determined based on colony forming units. Results: Candidacidal activities of the peroxidase and GO-PO systems increased with increasing concentrations of bLPO. This tendency was the same in the presence or absence of hyaluronic acid. Candidacidal activity of HEWL was not significantly concentration-dependent. Candidacidal activities of the GO-PO system were higher than those of the corresponding peroxidase system. Candidacidal activity was inhibited in the presence of hyaluronic acid in the following order: HEWL, the peroxidase system, and the GO-PO system. Conclusions: Hyaluronic acid inhibited the candidacidal activities of HEWL, the peroxidase system, and the GO-PO system. The GO-PO system exhibited better candidacidal activity than HEWL and the peroxidase system both in the presence and absence of hyaluronic acid.

The Influence of L1 on L2 -Perception of Korean Monophthongs by Polish Speakers- (외국어 습득에 모국어가 미치는 영향에 대하여 -폴란드어 화자의 한국어 단순 모음 청취에 대한 연구-)

  • Paradowska Anna IBabella
    • MALSORI
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    • no.39
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    • pp.73-86
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    • 2000
  • This paper aims to research the influence of mother tongue (Polish) on the perception of a foreign language (Korean) i.e. how vowel sounds that are totally unfamiliar to the listeners are perceived, how the similar sounds are perceived and whether the perception differs according to the phonetic values of the neighbouring sounds. As a result, the degree of the influence of Ll on the vowels of L2 is different in each case and mostly depends on the familiarity of the vowel in question and on the articulatory similarities between the vowels in both languages. The results are as follows; The best perception was observed with Korean /i/ and /a/ (very similar places of articulation in both languages). The worst degree of perception was Korean /(equation omitted)/ that is very unfamiliar to Polish subjects. Vowels that are not so different from the Ll sounds were perceived fairly well. Another important result is that Polish listeners seem to be more sensitive to lip rounding than to the height of the tongue. The role of the neighbouring sounds seems to be of a considerable importance, Depending on the preceding vowel, a sudden drop or rise in the degree of the perception was observed.

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The relationship between cross language phonetic influences and L2 proficiency in terms of VOT

  • Kim, Mi-Ryoung
    • Phonetics and Speech Sciences
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    • v.3 no.3
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    • pp.3-10
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    • 2011
  • This study examined the production of aspirated stop consonants in Korean and English words to address how the influences differed particularly in terms of proficiency in L2 English. Voice onset times (VOTs) were measured from two American monolinguals and seven Korean speakers. The results showed that VOT patterns for both L1 and L2 stops differed according to their proficiency in L2 English. In L2 English, high proficient speakers produced VOTs that were similar to those of native speakers of English whereas low proficient speakers produced VOTs that were significantly longer than those of proficient speakers. In L1 Korean and L2 English, most of the proficient speakers produced VOTs similarly. Unlike previous findings, Korean VOTs were even shorter than English counterparts. The VOT shortening of aspirated stops in Korean was found for most of the proficient speakers. The findings of the present study suggest that cross language phonetic influences as well as the ongoing VOT shortening in Korean aspirated stops may be correlated with L2 proficiency. Since this is a pilot study with a small number of subjects for each proficiency group, further quantitative study is necessary to generalize.

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Analysis of Lactobacillus Species Isolated from the Vagina of Korean Women (한국여성의 질내 Lactobacillus 균종분포)

  • Kim, Kack-Kyun;Kook, Yoon-Hoh;Chang, Woo-Hyun
    • The Journal of the Korean Society for Microbiology
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    • v.16 no.1
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    • pp.35-38
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    • 1981
  • Lactobacillus species isolated from posterior fornix of the vagina of 410 Korean women, who visited several local clinics and the Family Health Clinic of the Institute of Reproductive Medicine and Population, Seoul National University in Seoul were identified by their physiological and biochemical characteristics. And the results were as follows. 1) Of the 410 women 297(72.4%) gave the positive culture for Lactobacillus. 2) Isolated 200 strains were differentiated into following species. L. salivarius(43 strains, 18.7%) and L. leichmannii(42, 18.3%) were the most common species followed by L. plantarum(34, 14.8%) L.brevis(22, 9.6%), L. fermenti(19, 8.3%), L. cellobiosus(15, 6.5%), L. acidophilus(14, 6.1%), L. delbrueckii(10, 4.3%) and L. casei(1, 0.4%) and there were 30 strains(13%) which could not have been identified by the methods employed in this study. 3) Age seems to have no influence on the distribution of Lactobacillus species in vagina and it seems like that the overall distribution of Lactobacillus species in vagina does not change during the active reproductive period of women.

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