• Title/Summary/Keyword: $K_m$ value

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The Study on Tree Vigor of Damaged Forest by Thecodiplosis japonensis Uchida et Inouye (솔잎혹파리 피해임지의 수세변동에 관한 연구)

  • Lee, Chan-Yong;Chae, Hee-Mun;Kim, Jong-Kuk
    • Journal of Forest and Environmental Science
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    • v.16 no.1
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    • pp.34-41
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    • 2000
  • This study investigated tree vigor of damaged forest by Thecodiplosis japonensis Uchida et Inouye. In damaged forest by pine gall midge, the investigation result of damaged rate section (severe, moderate, light) indicated that severe stand showed higher value of electric resistance ($k{\Omega}$) than that of light stand, the investigation result of tree density section(crowed, middle, little) indicated that crowed stand showed higher value of electric resistance than that of little stand (the value of electric resistance at which low reading show high vigor tree and high reading low vigor tree). The crown width and DBH (diameter of breast height) of external factors showed lower value of electric resistance than that of small size. The results of comparative between Crown area and value of electric resistance in each stand were $13.4m^2$ in severe stand, $10.9m^2$ in moderate stand and $7.9m^2$ in light stand. Therefore, the tree which have big crown showed low value of electric resistance (below $15k{\Omega}$)that has high possible of survial.

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Comparison on the Dosimetry of TLD and PLD by Dose Area Product (DAP(Dose Area Product)를 이용한 TLD와 PLD의 선량 측정 비교)

  • Choi, Jae-Ho;Kang, Gu-Jun;Chang, Seo-Goo
    • The Journal of the Korea Contents Association
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    • v.12 no.3
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    • pp.244-250
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    • 2012
  • The results of analyzing the difference between performances of individual dosimeters on this research subjecting the PLD and TLD, which are the official personal dosimeters, through dosimetry are as follows. After scanning the integral dose using an automatic scanner, the values of two devices that went through dose adjustment process had a statistical difference in TLD and PLD measurements under each filming conditions which were 70kVp, 200mA, 0.012sec and 42kVp, 100mA, and 0.012sec (p<0.001 and p<0.001 respectively). As for the difference of measurement value between DAP and the two particles under 70kVp, 200mA, 0.012sec filming condition, TLD had a value lower than DAP average value by $44.2mGy{\cdot}cm^2$ and PLD had a value of $246.8mGy{\cdot}cm^2$ which was lower than DAP average value by $15.5mGy{\cdot}cm^2$, while under 42kVp, 100mA, 0.012sec filming condition, TLD had a value lower than DAP average value by $17.9mGy{\cdot}cm^2$ and PLD had a value of $82.6mGy{\cdot}cm^2$ which was lower than DAP average value by 7.6$mGy{\cdot}cm^2$. Also, compared to PLD, each of 10 devices measured dose value in TLD had a larger deviation between the particles, and for a reproducibility test which repeatedly measured one particle, PLD had ${\pm}1%$ which was lower than TLD's ${\pm}2%$. As such, PLD had a superior performance result in dose measurement capacities aspect compared to TLD, and therefore we could verify that PLD is more appropriate and advantageous in managing radiation-related task performing worker's personal radiation exposure management in the diagnostic radiation field.

Development of Vibration Absorption Device for the Transportation-Trailer System(I) - Characteristics for the existing vehicle - (수송 트레일러의 충격 흡수 장치 개발(I) - 보급기종에 대한 특성 및 진단 -)

  • 이홍주;홍종호;이성범;김성엽
    • Journal of Biosystems Engineering
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    • v.28 no.2
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    • pp.89-96
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    • 2003
  • This study was aimed to identify how the main body vibration of power tiller will be transmitted to the trailer, and to find out the basic information for demage reducing method of agricultural products during transportation. The vertical vibration acceleration level was measured at 6 positions, i.e. engine, hitch, seal and three parts of trailer (front middle, and rear) for the not driving but at the engine speeds of 1,000rpm and driving at 0.35m/s. The results of this research could be summarized as follows; 1. For not driving, the accumulated acceleration level up to 120Hz was 50% of total accelerations at engine part and those were 28~41% at other parts. Those up to 40Hz were 20~30% at engine and hitch part and 2~8% at trailer part. And those up to 20Hz were 13~20% at engine and hitch part and 1~4% at trailer part 2. For the driving with 0.35m/s at paved road, the average vertical accelerations were in the range of 0.005~0.058m/s$^2$. The lowest value of 0.005m/s$^2$ was showed at engine part and the value of 0.031-0.058m/s$^2$ was showed at trailer part. 3. For the driving with 0.35m/s, the accumulated value of average vertical accelerations showed the lowest value at engine parts md showed 5 times value of engine part at trailer part especially highest value at middle part of trailer. 4. For the driving with 0.35m/s, the accumulated acceleration level up to 120Hz was 75% of total accelerations at engine part and those were 20~42% at other parts. Ant those up to 20Hz and 40Hz were 24~26% at engine part and 0.1~0.6% at trailer part.

Aloesin and Arbutin Inhibit Typrosinase Activity in a Synergistic Manner via a Different Action Mechanism

  • Jin, Ying-Hua;Lee, Suk-Jin;Chung, Myung-Hee;Park, Jeong-Hill;Park, Young-In;Cho, Tae-Hyeong;Lee, Seung-Ki
    • Archives of Pharmacal Research
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    • v.22 no.3
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    • pp.232-236
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    • 1999
  • In this study, we present evidence that cotreatment of aloesin and arbutin inhibits tyrosinase activity in a synergistic manner by acting through a different action mechanism. Aloesin or arbutin similarly inhibited enzyme activity of human- and mushroom-tyrosinases with an IC50 value of 0.1 or 0.04 mM, respectively. Lineweaver-Burk plots of the enzyme kinetics data showed that aloesin inhibited tyrosinase activity noncompetitively with a Ki value of 5.3 mM, whereas arbutin did it competitively (Maeda, 1996). We then examined whether cotreatment of these agents inhibits the tyrosinase activity in a synergistic manner. The results showed that 0.01 mM aloesin in the presence of 0.03 mM arbutin inhibited activity of mushroom by 80% of the control value and the reverse was also true. The inhibitory effects were calculated to be synergistic according to the B rgi method. Taken together, we suggest that aloesin along with arbutin inhibits in synergy melanin production by combined mechanisms of noncompetitive and competitive inhibitions of tyrosinase activity.

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Bioassay Study on fresh Water Fish with PCP and DDT (PCP와 DDT의 독성이 담수어에 미치는 영향)

  • Byung Soo Yang
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.17 no.2
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    • pp.77-83
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    • 1981
  • Four-day bioassay method was used in this study to find out toxicity levels of DDT and PCP. From this study it was found that M. chrysophekadion was the most sensitive to DDT with a 96 h-TL sub(m) value of 0.0044 mg/l followed by P. Sutchi with a 96 h-TL sub(m) value of 0.0056 mg/l, and the most resistant was C. Siamensis with a 96 h-TL sub(m) value of 0.0133 mg/l. In the case of PCP, it was also found that M. Chrysophekadion and P. Sutchi were the first and second most sensitive to PCP with a 96 h-TL sub(m) value of 0.065mg/l PCP and 0.125mg/l PCP respectively, as in the case of DDT study. T. Nilotica was found to be the most resistant to PCP with a 96 h-TL sub(m) value of 0.264mg/l PCP. The resistant power of fish to pollution varies with the species of fish and the types of pollutants. In order of decreasing sensitivity of fish to DDT based on TL sub(m), the following sequence is obtained M. Chrysophekadion, P. Sutchi, T Nilotica, P. Gonionotus, K. Bicirrhis, L. Bicolor, C. Carpio, R. Heteromorpha, C. Siamensis while in the case of PCP, M. Chrysophekadion, P. sutchi, L. Bicolor, K. Bicirrhis, P. Gonionotus (R. Heteromorpha, R. Trilineata), C. Siamensis, C. Carpio, T. Nilotica.

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Discharge Waveform Properties on Electrical Sterilization by HV Impulse (고전압 펄스에 의한 전기 살균에서 방전 파형의 특성 분석)

  • Lee, H.K.;Suehiro, J.;Hara, M.;Lee, D.C.
    • Proceedings of the KIEE Conference
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    • 1998.11c
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    • pp.944-946
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    • 1998
  • We evaluated cell survivability by changing RLC value on HV impulse network. When the L value is changed from 0 to 10mH in this circuit. we found that cell survivability is shown large decline with 4mH of L value. I respect to this result, when waveshapes of oscillatory decay are presented along the variation of L value in RLC circuit, we analyzed whether discharge waveform properties have an effect on sterilization ratio, and measured threshold voltage as the minimum peak voltage of a single pulse which can sterilize cells. Finally, we found that the sterilization effect was related to number of threshold voltage waveforms being applied.

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Interaction of Antihistaminics with Muscarinic Receptor(I) -Action on the cardiac muscarinic receptor- (항(抗) Histamine제(劑)와 Muscarinic Receptor와의 상호작용(相互作用)(I) -심장(心臟) muscarinic receptor에 대한 작용(作用)-)

  • Lee, Shin-Woong;Park, Yeung-Joo;Lee, Jeung-Soo;Ha, Kwang-Won;Jin, Kap-Duck
    • YAKHAK HOEJI
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    • v.32 no.2
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    • pp.101-111
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    • 1988
  • $[^3H]$ Quinuclidinyl benzilate(QNB) binding assays were performed in the dog ventricular sarcolemma fraction enriched approx. 32-fold in sarcolemma compared to the starting homogenate to elucidate the effect of antihistaminics on cardiac muscarinic receptor. Chlorpheniramine(CHP) inhibited specific binding of $[^3H]$QNB and delayed the equilibrium binding. The rate constants at $37^{\circ}C$ for formation and dissociation of the QNB receptor complex were $0.38{\times}10^9\;M^{-1}$ and $1.6{\times}10^{-2}\;min^{-1}$, respectively. The mean value for the dissociation constant from the pairs of the rate constants was 43. 2 pM and this value was similar to the value(44.8pM) determined from Scatchard analysis. CHP decreased association rate constant, indicating increase in $K_D$ value. Decrease in affinity without affecting the binding site concentration$(B_{max})$ for $[^3H]$QNB binding by CHP was also demonstrated by Scatchard analysis. $K_i$ values for $H_i$-blockers that inhibited specific $[^3H]$QNB binding were $0.02{\sim}4.8{\mu}M$. Cimetidine with $K_i$ value of $230{\mu}M$, however, was ineffective in displacing $[^3H]$QNB binding at concentration of $50{\mu}M$. The Hill coefficient for $H_1$-blockers were about one. The results indicate that $H_1$-antihistaminics inhibit $[^3H]$ QNB binding by interaction with myocardiac muscarinic cholinergic receptor and anticholinergic side effects of these drugs are mainly due to this receptor blocking mechanism.

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A Study of the Printability Coefficients on the Newspaper ( II ) - Limiting printed density ($D_{\infty}$) and printed density smoothness constant m value- (신문용지의 인쇄적성 계수에 관한 연구 ( 제 2 보 ) -최대 잉크 색 농도 ($D_{\infty}$), 색 농도 평활성 계수 ${\ulcorner}m{\lrcorner}$ 값 -)

  • Ha, Young-Baeck;Kim, Chang-Keun;Oh, Sung-Sang;Lee, Yong-Kyu;Youn, Jong-Tae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.2 s.115
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    • pp.16-21
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    • 2006
  • Uneven ink transfer of a print can be traced to several causes such as an incomplete contact between the paper surface and ink film, a coarse pattern of a continuous ink film after transfer, uneven absorption, etc. Uneven ink transfer was studied in this points by the Tollenaar. Uneven distributions of printed density are reflected in low ${\ulcorner}m{\lrcorner}$ values of the print. Tollenaar's smoothness coefficient ${\ulcorner}m{\lrcorner}$ value was important factor that deciding printed quality which was easily obtain by densitometry. Limiting print density $D_{\infty}$ that obtained Tollenaar's formulation working as a influence factor at the printed quality. In this study, we obtained limiting print density $D_{\infty}$ and smoothness coefficient ${\ulcorner}m{\lrcorner}$ value of domestic newspapers and foreign newspapers. And we analyzed about properties of the newspaper. The result of this study, smoothness coefficient ${\ulcorner}m{\lrcorner}$ value and limiting print density $D_{\infty}$ showed the good results in the low porosity and low roughness newspaper. Datum which obtained by this study was used as printability factor for the quality control and improvement of domestic newspaper and wished to apply as a basic data for the domestic newspaper quality.

A converting method for square wave to average value in real time (실시간 구형파-평균치 변환 방법)

  • Lee, J.M.;Kim, C.K.;Kim, S.J.;Cheon, J.M.;Park, M.K.;Kwon, S.M.
    • Proceedings of the KIEE Conference
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    • 2006.10c
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    • pp.585-587
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    • 2006
  • Generally, LPF(low pass filter) circuits are used for converting square wave to average value, but these are not used necessary for average value of square wave in real time because of time constant of LPF. This paper deals with acquiring method for average value of square wave in real tine in case of frequency of output voltage is fixed, waveform of output voltage is square wave and duty of output voltage is varied like as 1 quadrant or 4 quadrant chopper.

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