• Title/Summary/Keyword: buffer time

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PHENOLOXIDASE AND ANTIOXIDANT IN KOREAN GINSENG (고려인삼에 있어서의 페놀 산화효소의 항산화물질)

  • Park E.Y.;Luh B.S.;Branen A.L.
    • Proceedings of the Ginseng society Conference
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    • 1984.09a
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    • pp.257-275
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    • 1984
  • Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.

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A Study on the Location Selection of Low-Floor Bus Stop using the Use Information of the Mobility Support Center (교통약자 이동지원센터의 이용정보를 활용한 저상버스 정류장 입지선정에 관한 연구)

  • Park, Jae-Kook
    • Journal of Industrial Convergence
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    • v.18 no.1
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    • pp.25-33
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    • 2020
  • South Korea entered an aged society phase in 2017 with the elderly accounting for 14% or higher of the entire population. It is expected to enter a super-aged society phase in 2026. The mobility handicapped, including the disabled and the elderly, are expected to grow continuously, and the demand for transport service for the mobility handicapped will definitely increase further. Thus, there is thus a need for various research to increase the utilization rate of low-floor buses among the mobility handicapped. This study analyzed the locations of getting on and off transportation means, time of departure and arrival, purpose of use, and frequency of use by the day among the mobility handicapped by making use of the information about their use of special transport service run by the mobility support center for the mobility handicapped. The study then proposed a method of selecting locations for low-floor bus stops to reflect the distribution and need of getting on and off transportation means among the mobility handicapped with such spatial analysis techniques as geocoding, overlapping analysis, buffer analysis, and generate tessellations. Finally, the study selected 228 locations for low-floor bus stops in Cheonan and reported a need to add 35 low-floor bus stops after eliminating the ones where the locations overlapped the old ones.

Phosphatidic Acid Production by PLD Covalently Immobilized on Porous Membrane (공유결합으로 다공성 막에 고정화된 PLD에 의한 포스퍼티딕산 생산)

  • Park, Jin-Won
    • Clean Technology
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    • v.21 no.4
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    • pp.224-228
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    • 2015
  • Phospholipase D (PLD) was immobilized on a submicro-porous membrane through covalent immobilization. The immobilization was conducted on the porous membrane surface with the treatment of polyethyleneimine, glutaraldehyde, and the anhydrase, in sequence. The immobilization was confirmed using X-ray photon spectrometer. The pH values of phosphatidylcholine (PC) dispersion solution with buffer were monitored with respect to time to calculate the catalytic activities of PC for free and immobilized PLD. The catalytic rate constant values for free PLD, immobilized PLD on polystyrene nanoparticles, and immobilized PLD on a porous cellulose acetate membrane were 0.75, 0.64, and 0.52 s-1, respectively. Reusability was studied up to 10 cycles of PC hydrolysis. The activity for the PLD immobilized on the membrane was kept to 95% after 10 cycles, and comparable to the PLD on the nanoparticles. The stabilities for heat and storage were also investigated for the three cases. The results suggested that the PLD immobilized on the membrane had the least loss rate of the activity compared to the others. From these studies, the porous membrane was feasible as a carrier for the PLD immobilization in the production of phosphatidic acid.

Effect of Phenobarbital on the Hepatic Clearance of Diltiazem in Isolated Rat Hepatocytes (흰쥐 분리 간세포에 있어서 딜티아젬의 간클리어런스에 미치는 페노바르비탈의 영향)

  • Lee, Yong-Bok;Oh, Joon-Kyo;Kho, Ik-Bae
    • Journal of Pharmaceutical Investigation
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    • v.26 no.1
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    • pp.33-41
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    • 1996
  • In order to study the effect of phenobarbital(PB) on the hepatic transport of diltiazem(DTZ), $Ca^{2+}$ channel blocker, we used isolated hepatocytes of rat which was intraperitoneally pretreated with phenobarbital sodium(75 mg/kg) for four days once a day. For the isolation of rat liver cells, a modification of the two step procedure of Seglen was used. DTZ was dissolved in incubation buffer to the final DTZ concentrations of 200, 400, 600, 800 and 1000 ng/ml in order to elucidate the uptake characteristics of DTZ by hepatocytes. Reactions were stopped at 10, 20, 30, 45, 60, 90, 120 and 300 sec. The initial velocity was determined by disappearance of diltiazem in the hepatocyte suspension. On the other hand, to determine the effect of PB on the in vitro hepatic intrinsic clearance of DTZ we obtained the metabolism rates of DTZ in the control and the PB-pretreated rat hepatocyte at various time intervals. According to pretreatment with PB, the size of hepatocyte and the amount of protein per $10^6$ cells were significantly (p<0.01) increased from $26.92{\pm}0.1364\;m$ to $35.31{\pm}1.00\;m$ and from $468{\pm}6.5\;{\mu}g/10^6$ cells to $628.8{\pm}12.1{\mu}g/10^6$ cells, respectively. In the case or hepatic uptake of diltiazem, $K_m$ was not different in the normalization by cell numbers and increased from $2.90\;{\mu}M\;to\;13.89\;{\mu}M$ in the normalization by protein amount. $V_max$ was increased regardless of normalization by protein amount and cell numbers, from $1.21\;{\mu}mole/min \;{\cdot}\;mg\;protein\;to\;3.96\;{\mu}mole/min\;{\cdot}\;mg\;protein\;and\;from\;2.38\;{\mu}mole/min\;{\cdot}\;10^6\;cells\;to\;2.83\;{\mu}mole/min\;{\cdot}\;10^6\;cells$, respectively. The in vitro hepatic intrinsic clearance of DTZ was significantly (p<0.01) increased from $0.640{\pm}0.038\;ml/mim\;{\cdot}\;10^6\;cells\;to\;2.385{\pm}0.212\;ml/min\;{\cdot}\;10^6\;cells$ due to PB-pretreatment. These results suggest that the uptake of DTZ by hepatocyte is extremely fast and PB enhances the hepatic intrinsic metabolic clearance of DTZ.

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Bioequivalence of Neuracetam Tablet to Neuromed Tablet (Oxiracetam 800 mg) (뉴로메드정(옥시라세탐 800 mg)에 대한 뉴라세탐정의 생물학적동등성)

  • Choi, Sung-Up;Kim, Jong-Seok;Yoon, Mi-Kyeong;Kim, Jung-Il;Park, Seok;Han, Sang-Beom;Lee, Jae-Hwi;Choi, Young-Wook
    • Journal of Pharmaceutical Investigation
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    • v.34 no.3
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    • pp.215-222
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    • 2004
  • The purpose of the present study was designed to evaluate the bioequivalence of two oxiracetam tablets, Neuromed tablet (Korea Drug Co., reference drug) and Neuracetam tablet (Sam Jin Pharmaceutical Co., test drug), according to the guidelines of Korea Food and Drug Administration (KFDA). Release of oxiracetam from the tablet in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty-four healthy volunteers, $23.7\;{\pm}\;2.4$ year in age and $68.9\;{\pm}\;6.2$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was performed. After oral administration of a tablet containing 800 mg of oxiracetam, blood samples were taken at predetermined time intervals and concentrations of oxiracetam in plasma were determined using HPLC-MS-MS. The dissolution profiles of two formulations were very similar at all dissolution media. In addition, pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$ and $C_{max}$ untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug were 0.42%, 0.45% and -12.58% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals for the log transformed data were within the acceptance range of log 0.8 to log 1.25 (e.g., $log0.94{\sim}log1.06$ and $log0.90{\sim}log1.07$ for $AUC_t$, and $C_{max}$, respectively), indicating that Neuracetam tablet is bioequivalent to Neuromed tablet. The major pharmacokinetic parameters, $AUC_t$, and $C_{max}$ met the criteria set by KFDA for bioequivalence indicating that Neuracetam tablet is bioequivalent to Neuromed tablet.

A Sensitivity Study on Nuclide Release from the Near-field of the Pyroprocessed Waste Repository System: Part 1. A Probabilistic Approach (파이로처리 폐기물 처분 시스템 근계 영역 내 핵종 유출 민감도: 제 1 부 확률론적 접근)

  • Lee, Youn-Myoung;Jeong, Jongtae
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.12 no.1
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    • pp.19-35
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    • 2014
  • A parametric sensitivity to the annual exposure dose rate to the farming exposure group has been probabilistically carried out for three principal elements associated with the nuclide transport behavior in the near-field of the pyroprocessed waste repository system. Credit time for both metal and ceramic containers, annual nuclide release rete, and the degree of loss of bentonite buffer around the container are selected as the elements and investigated for important nuclides. All the elements are shown to be sensitive to the results. Methodology studied through this study and the results are expected to make a good feedback to the repository design. As a follow-up study, separated in Part 2, the A-KRS will be deterministically assessed and then compared among each other with the normal, the worst, and the best case scenarios associated with their extreme values these elements could have.

Design of a High Throughput Parallel Turbo Decoder (고 처리율 병렬 터보 복호기 설계)

  • Lee, Won-Ho;Park, Heemin;Rim, Chong S.
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.11
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    • pp.50-57
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    • 2013
  • This paper provides a design of high-throughput parallel turbo decoder that is able to decode several packets of various length simultaneously. For high-speed communications, designing of Turbo decoder as parallel structures reduces the long decoding time caused by iterative turbo decode way. Also, by employing the double buffer structure for input and output packets improves the decoder throughput by enabling continuous decoding. Because parallel turbo decoder is designed to be able to decode the packet of the longest length, there exist idle PE's(Processing Element) in the case of decoding packets of short length. The main idea of this paper is to increase the utilization of PE's in parallel Turbo decoder and to improve the decoder throughput by using the idle PE's immediately for the subsequent packets decoding. For this, the control is necessary to enable the concurrent decoding of several short packets and we propose the method of this control. Applying the proposed method, we implemented Turbo Decoder with 32 PE's that can decode packets of 6144 bits maximum. Compared to the conventional Turbo decoder, although the area was increased about 16%, the decoder throughput was improved 28 times for short packets.

제안기반 자동 거래협상 시장에서의 사용자 에이전트를 위한 최적 거래안 탐색 전략의 개발

  • 홍준석;김우주;송용욱
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2002.05a
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    • pp.140-148
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    • 2002
  • 컴퓨터를 통해 편리한 생활을 추구해온 인간들은 전자상거래 분야에서도 이러한 욕구를 충족시키기 위해 자동협상이라는 기능을 요구하게 되었다. 지능형 에이전트를 이용한 자동협상은 인간의 거래협상 업무의 부담을 많은 부분을 덜어주고 있어 자동협상 에이전트에 관한 연구들이 활성화되고 있다 소비자간 전자상거래에서는 다수의 자동협상 에이전트 연구들이 경매시장에서의 자동협상에 초점을 맞추고 있는데 반해, 가격 이외의 여러 거래속성을 갖는 상품에 대한 제안기반 협상시장에서의 자동협상 에이전트에 관한 연구들이 최근에 활발히 이루어지고 있다. 본 연구에서는 소비자간 전자상거래에서 거래속성의 변화에 따라 개인의 효용가치의 차이를 이용한 다속성 상품의 제안기반 협상시장이 가져야할 특성에 대해 연구하고, 이를 기반으로 자동 거래협상을 수행에 필요한 거래속성 변화에 따른 소비자 개인의 선호체계를 표현하기 위한 방법을 개발하였다. 그리고 이러한 자동 거래협상을 공정하게 수행하기 위해 협상시장이 가져야할 특징과 프로토콜을 제안하고 시장운영 에이전트 시스템의 구조를 설계하였다. 마지막으로 이러한 분산형 시장구조를 갖는 제안기반의 협상시장에 참여하는 사용자 에이전트 시스템이 최적의 거래상대와 최적의 거래안을 찾기 위한 탐색방법을 구체적으로 개발하였다. 본 연구의 결과를 통하여 소비자간 전자상거래에서 구매자 뿐만 아니라 판매자도 협상결과에 따른 거래로 얻어지는 자신의 효용을 극대화할 수 있는 공정한 협상시장을 운영할 수 있을 뿐만 아니라 사용자들도 손쉽게 자신의 협상 선호체계를 쉽게 표현하고, 표현된 선호체계를 반영한 자동 거래협상을 수행할 수 있을 것 이다. 기존의 UN/EDIFACT표준을 사용하고 있는 EDI환경과 기존 VAN 방식의 EDI 중계 시스템과 연동되며, 향후 관세청의 XML/EDI 표준 시행을 미리 대비하는 선도연구로서 자리매김이 된다. 본 연구에서는 개발된 XML/EDI 통관시스템은 향후, 서비스의 최대 걸림돌이 되어왔던 값비싼 EDI 사용료의 부담에서 벗어날 수 있게 할 것이며, 저렴한 EDI구축/운영 비용으로 전자문서교환의 활성화와 XML이 인터넷 기반의 문서유통 표준으로 자리매김할 수 있는 중요한 계기가 될 것이다.재무/비재무적 지표를 고려한 인공신경망기법의 예측적중률이 높은 것으로 나타났다. 즉, 로지스틱회귀 분석의 재무적 지표모형은 훈련, 시험용이 84.45%, 85.10%인 반면, 재무/비재무적 지표모형은 84.45%, 85.08%로서 거의 동일한 예측적중률을 가졌으나 인공신경망기법 분석에서는 재무적 지표모형이 92.23%, 85.10%인 반면, 재무/비재무적 지표모형에서는 91.12%, 88.06%로서 향상된 예측적중률을 나타내었다.ting LMS according to increasing the step-size parameter $\mu$ in the experimentally computed. learning curve. Also we find that convergence speed of proposed algorithm is increased by (B+1) time proportional to B which B is the number of recycled data buffer without

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Using Numerical Maps to Select Solar Panel Installation Sites no Expressway Slopes (수치지도를 이용한 고속국도 주변 태양광 패널 설치 대상지 선정)

  • Jung, Jaehoon;Kim, Byungil
    • Korean Journal of Construction Engineering and Management
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    • v.17 no.5
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    • pp.71-77
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    • 2016
  • Solar energy is a viable source to replace fossil fuels. However, challenges associated with site selection for solar panel installation inhibit the uptake of solar energy systems. Expressway slopes offer a potentially attractive alternative for solar panel installation for the following reasons: expressway slopes are vacant public sites, they are abundant (about 4,193km in South Korea), and they are linear in nature. Traditoinally when selecting sites for solar systems conventional surveying methods are employed. Unfortunately, these methods can be dangerous, time consuming, and labor intensive. To overcome these limitations of conventional site selection methodologies, we propose an automated approach using numerical maps. First, contour and expressway polylines are extracted separately from numeric maps. The extracted contour lines are then converted into a digital terrain model; this is used to calculate aspect and slope information. Next, the extracted expressway lines are projected onto a binary image and refined to recover the disconnections, and then applied to create a buffer zone to narrow the search space. Finally, all data sets are overlaid to identify candidate sites for solar panel systems and are visually verified through comparisons with aerial photos.

Simultaneous Determination of Berberine, Cinnamic Acid and Glycyrrhizin in Pharmaceutical Formulations by Capillary Electrophoresis with Diode-Array Detection (모세관 전기이동법에 의한 생약제제중 베르베린, 계피산 및 글리시리진의 동시 정량)

  • Kang, Seong Ho;Chung, Wha Jin;Yoon, Hyung Jung;Chung, Doo Soo
    • Journal of the Korean Chemical Society
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    • v.41 no.2
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    • pp.98-104
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    • 1997
  • A simple, accurate and reproducible capillary electrophoresis(CE) assay has been developed for the determination of berberine, cinnamic acid, and glycyrrhizin which are used in traditional Korean medicinal preparations. Separation of these compounds was performed in 20 mM phosphate buffer(pH 7.5) and acetonitrile(75:25, v/v) using a bare fused silica capillary($57 cm{\times}75 {\mu}m$ i.d.) at 25$^{\circ}C$. With the electric field of 350 V/cm, the time needed for the separation of berberine, cinnamic acid and glycyrrhizin was within 13 min. Calibration curves were linear for 1∼100 ${\mu}g/mL$ berberine, 0.3∼100 ${\mu}g/mL$ cinnamic acid and 2.5∼100 ${\mu}g/mL$ glycyrrhizin. The ranges of relative standard deviations(n=5) for those samples were between 0.96∼2.35%. The limits of detection(S/N=3) for berberine, cinnamic acid and glycyrrhizin were 0.5, 0.1 and 2.0 ${\mu}g/mL$, respectively. The numbers of theoretical plates were 181,000(berberine), 88,000(cinnamic acid) and 169,000(glycyrrhizin), while they were 3,100∼4,800 in HPLC.

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