• Title/Summary/Keyword: AM to AM

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Sequential separation of 90Sr, 241Am, 239,240Pu and 238Pu by radioanalytical techniques (방사능 분석기술을 이용한 90Sr, 239,240Pu, 238Pu, 241Am 축차분리)

  • Lee, Myung Ho;Park, Kyoung Kyun;Kim, Jong-Yun;Park, Yeong Jae;Kim, Won Ho
    • Analytical Science and Technology
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    • v.18 no.6
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    • pp.469-474
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    • 2005
  • This paper presents a quantitative method of sequential separation of $^{90}Sr$, $^{241}Am$ and Pu radionuclides with an anion exchange resin and a Sr-Spec resin. The Pu isotopes were purified with an anion exchange resin. The americium and strontium fractions were separated from the matrix elements with an oxalate co-precipitation method. Americium fraction was separated from the strontium fraction with iron co-precipitation method and purified from lanthanides with anion exchange resin. Strontium-90 was purified from other hindrance elements with the Sr-Spec resin after oxalate co-precipitation. The measurement of Pu and Am isotopes was carried out by an ${\alpha}$-spectrometer. Strontium-90 was measured by a liquid scintillation counter. The radiochemical procedure of $^{90}Sr$, $^{241}Am$ and Pu radionuclides investigated in this study has been validated by application to IAEA-Reference soils.

ACPR Analysis of Millimeterwave OFDM System with Power Amplifier's Phase Distortion (전력증폭기 위상왜곡에 의한 밀리미터파 OFDM 시스템의 ACPR 해석)

  • Roh, Hee-Jung
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.5
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    • pp.151-155
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    • 2004
  • Millimeterwave OFDM wireless LAN system has been modeled for ACPR analysis. With simple AM-to-PM modeling for power amplifier and system simulation technique, power amplifier ACPR is simulated for OFDM modulation, Also, amplifier back-off value satisfying the required ACPR and the ACPR degradation have been predicted with the measured and modeled AM-tn-PM distortion.

Effect of Cyclodextrins on the Solubility and Stability of Aspalatone in Aqueous Solutions (수용액중 시클로덱스트린류가 아스팔라톤의 용해성과 안정성에 미치는 영향)

  • Gwak, Hye-Sun;Chun, In-Koo
    • Journal of Pharmaceutical Investigation
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    • v.30 no.4
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    • pp.267-271
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    • 2000
  • The effect of cyclodextrins on the solubility and stability of aspalatone (acetylsalicylic acid maltol ester, AM, CAS 147249-33-0), which has been recently found to have an antithrombotic effect, was investigated. The addition of ${\beta}-cyclodextrin\;({\beta}-CD),\;dimethyl-{\beta}-cyclodextrin\;(DMCD)\;or\;2-hydroxypropyl-{\beta}-cyclodextrin\;(HPCD)$ to the aqueous solution increased the solubility of AM concentration-dependently. From the phase solubility diagram, stability constants for $AM-{\beta}-CD$, -DMCD or -HPCD complexes were calculated to be 43.1, 78.3 and $53.0\;M^{-1}$. The addition of ${\beta}-CD$, DMCD or HPCD to AM solution retarded the degradation rate of AM in the acidic region. However, ${\beta}-CD$ and HPCD rather acted as an accelerator of degradation in the neutral and alkaline regions. DMCD had a stabilizing effect at all pHs studied.

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A Dynamic assignment model for Dynamic Traffic Management in AM Peak (오전 첨두시의 동적 교통관리를 위한 동적 통행배정모형에 관한 연구)

  • 박준식;박창호;전경수
    • Journal of Korean Society of Transportation
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    • v.19 no.4
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    • pp.97-108
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    • 2001
  • A dynamic transportation management should be applied specially in AM peak because AM peak is more critical than PM peak in traffic volume and demand. AM peak trip can be characterized by commuting and schooling. which have the high level of usage on public transportation, and constraint on arrival time. So transportation management applied in AM peak could deal with a mode choice and an arrival time constrain. Researchers were involved in the dynamic transportation assignment models for management of congested traffic network. But, there were no models which considered a mode choice and an arrival time constrain should be included in management of AM peak. So there are limits to use exist models to control and analyze AM peak traffic. In this study, it is proposed the combined dynamic transportation model, considering a mode choice and the start time selection with arrival time constrains, based on Ran and Boyce's model. The proposed model is verified the compatibility by applying to the newly designed time space expanded network. The result shows that proposed model consistent with dynamic user optimal travel pattern. From this we certificate the applicability of the proposed model to control and analyze AM peak traffic.

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Platelet-Activating Factor Enhances Interleukin-1 Activity by Alveolar Macrophages : Inhibition by PAF Specific Receptor Antagonists

  • Lee, Ji-Hee
    • The Korean Journal of Physiology and Pharmacology
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    • v.1 no.2
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    • pp.201-208
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    • 1997
  • It is becoming increasingly clear that the inflammatory reaction can be ascribed to a complex array of mediators generated and released from activated phagocytes. In this study, the effect of PAF on interleukin-1(IL-1) activity by rat alveolar macrophages(AM) was examined using thymocyte proliferation assay in the supernate of sample obtained after 24 hr culture. When AM were cultured with PAF alone, no change in IL-1 activity was observed. However, the combined addition of PAF and muramyl dipeptide(MDP) or lipopolysaccharide(LPS) to AM cultures markedly enhanced IL-1 activity by 2-3 fold compared with AM cultures with the stimulant alone in a concentration dependent fashion. The peack effect was found at $10^{-8}$ M PAF with MDP and $10^{-14}$ M PAF with LPS. the effect of PAF was also tested in silica, toxic respirable dust, -added AM cultures as well as in the cultures containing bacterial compounds. Although silica did not stimulate the IL-1 activity, PAF could enhance IL-1 activity by 2 fold above the value of the silica-treated AM cultures with the peak response at $10^{-12}$ M PAF. Optimal enhancement of IL-1 activity occured when MDP and PAF were present together at the initiation of the 24 hr AM cultures. Additionaly, the biologically inactive precursor/metabolite of PAF, lyso-PAF failed to induce enhancement of IL-1 activity. When the specific, but structurally different PAF receptor antagonists, BN 52021($10^{-5}$ M) and CV 3988($10^{-5}$ M) was treated 15 min before addition of PAF($10^{-8}$ M) and MDP$(10\;{\mu}g/ml)$ to the AM cultures, it markedly inhibited the enhancement of IL-1 activity induced by PAF. The effects of these PAF antagonists were also observed in LPS$(10\;{\mu}g/ml)$-stimulated cells. Collectively, these data suggest that PAF enhances IL-1 activity by interaction with a specific receptor.

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A Literature Study on the Application of Sa-am Acupuncture for the Treatment of Stroke (중풍(中風)에 대한 사암침법(舍岩鍼法)의 운용(運用)에 관한 문헌(文獻) 연구 - ${\ll}$사암침구정전(舍岩鍼灸正傳)${\gg}$${\ll}$동의보감(東醫寶鑑)${\gg}$${\ll}$침구대성(鍼灸大成)${\gg}$과의 비교연구 -)

  • Lee, Jung-Tae;Yim, Yun-Kyoung
    • Journal of Acupuncture Research
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    • v.23 no.5
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    • pp.115-125
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    • 2006
  • Objectives & methods : This study aimed to investigate and compare the traditional acupuncture treatment and Sa-am acupuncture treatment of stroke. We investigated ${\ll}$Sa-am chimgujeongjeon(舍岩鍼灸正傳)${\gg}$ for Sa-am acupuncture treatment, and ${\ll}$Dongeuibogam(東醫寶鑑)${\gg}$ and ${\ll}$Chimgudaesung (鍼灸大成)${\gg}$ for traditional acupuncture treatment. Results & Conclusion : 1. In the traditional acupuncture treatment, acupoints on CV, GV, GB, LI, ST meridians to remove pathogens such as fire, damp, phlegm, blood stagnation and Ashi points (nearby points) are often used rather than acupoints according to the diagnosis of excess & deficiency in organs and meridians. 2. In ${\ll}$Sa-am chimgujungjeon(舍岩鍼灸正傳)${\gg}$, symptoms of stroke are classified into 21 and each symptoms are analyzed according to the diagnosis of excess & deficiency of organs and meridians, consequently treated using tonification & sedation of corresponding meridians. 3. For the treatment of stroke in ${\ll}$Sa-am chimgujungjeon(舍岩鍼灸正傳)${\gg}$, tonification & sedation of the acupoints on related meridian is often omitted, using only the acupoints on targeted meridian. 4. In ${\ll}$Sa-am chimgujungjeon(舍岩鍼灸正傳)${\gg}$, empirical points are preferably used for the treatment of stroke.

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Seasonal Changes in Colonization and Spore Density of Arbuscular-Mycorrhizae in Citrus Groves (감귤뿌리에서의 Arbuscular-Mycorrhizae 형성과 감귤원 토양중 포자밀도의 계절적 변화)

  • Kim, Sang-Youb;Oh, Hyun-Woo;Moon, Doo-Khil;Han, Hae-Ryong;Chung, Jong-Bae
    • Korean Journal of Environmental Agriculture
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    • v.17 no.2
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    • pp.174-181
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    • 1998
  • In four citrus grow of Satsuma mandarin (rootstock of trifoliate orange) including two grove of organical management and two groves of conventional management, spores of arbuscular mycorrhizal(AM) fungi were identified and seasonal changes in spore density in soils and AM colonization of citrus roots were investigated. AM colonization in weeds found in the groves were also examined. Three species of Glomus (G.deserticola, G. vesiculiferum, G. rubiforme ) and one unknown species of Acaulospora were observed in all of the groves. Annual mean density of AM fungal spores were in the range of 10,000${\sim}$40,000 per 100g soil with more spores in the organically-managed groves. The least spores were observed in December in all groves, and the most spores in April in the organically-managed groves while in February or April in the conventionally- managed. Annual mean AM colonization more 27% of citrus root were observed in the organically-managed with the high peaks in April and October and the minimum in August, while mean colonization less than 15% in the conventionally-managed with the peak in February and the minimum in different times depending on groves and years. AM colonization corresponded to a sigmoidal curve consisting of a laf phase during winter and a subsequent increase in spring, then succeeded by a maximum, and then a decrease at the end of vegetation. Fungal spore density and AM colonization showed a parallel pattern during the sample period. The seasonality appeared to be related more to the phenology of the plant than to the soil factors. Generally more spore density and AM colonization were found in organically managed groves. AM colonization was not correlated with available P and organic matter content in soil in this field investigation. Among sixteen weed species found in the groves, Astrogalus sinicus of Leguminosae, Portulaca oleracea of Portulacaceae showed high colonization in all groves and they can be considered as a source of inoculumn and host plants for propagation of AM fungi.

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An analysis of the arm-type site binding domain of bacteriophage .lambda. integrase

  • Cho, Eun-Hee
    • Journal of Microbiology
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    • v.33 no.2
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    • pp.165-170
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    • 1995
  • The 356 amino acid long lambda integrase protein of bacteriophage .lambda. constains two autonomous DNA binding domains with distinct sequence specificities. The amino terminal domain of integrase is implicated to bind to the arm-type sequences and the carboxyl domain interacts with the coretype sequencess. As a first step to understand the molecular mechanism of the integrase-DNA interaction at the arm-type site, the int(am)94 gene carrying an amber mutation at the 94th codon of the int was cloned under the control of the P$\_$tac/ promoter and the lacI$\_$q/ gene. The Int(am)94 mutant protein of amino terminal 93 amino acid residues can be produced at high level from a suppressor free strain harboring the plasmid pInt(am)94. The arm-type binding activity of Int(am)94 were measured in vivo and in vitro. A comparison of the arm-type binding properties of the wild-type integrase and the truncated Int(am)94 mutant indicated that the truncated fragment containing 93 amino acid residues carry all the determinants for DNA binding at the arm-type sites.

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Anti-inflammatory and anti-nociceptive effects of extract of Astragalus membranaceous

  • Kim, Young-Ock;Kim, Su-Kang;Cho, Ah-Rang;Chung, Joo-Ho
    • Advances in Traditional Medicine
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    • v.7 no.5
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    • pp.569-572
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    • 2008
  • The root of Astragalus membranaceous (AM) has been used to treat edema and arthritis in the traditional Korean medicine. To elucidate the anti-inflammatory and anti-nociceptive effects of ethanol extract of AM, the carrageenan-induced paw edema using a plethysmometer and thermal hypersensitivity using the plantar test were measured. Ibuprofen was used as a control drug. Pretreatment with AM (400 mg/kg p.o.) significantly reduced paw edema, compared to the carrageenan-treated rats. In the plantar test, the thermal withdrawal latency in AM-treated group was significantly increased than the carrageenan-treated group. The results indicate that AM could have be the anti-inflammatory and anti-nociceptive properties.

In situ monitoring-based feature extraction for metal additive manufacturing products warpage prediction

  • Lee, Jungeon;Baek, Adrian M. Chung;Kim, Namhun;Kwon, Daeil
    • Smart Structures and Systems
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    • v.29 no.6
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    • pp.767-775
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    • 2022
  • Metal additive manufacturing (AM), also known as metal three-dimensional (3D) printing, produces 3D metal products by repeatedly adding and solidifying metal materials layer by layer. During the metal AM process, products experience repeated local melting and cooling using a laser or electron beam, resulting in product defects, such as warpage, cracks, and internal pores. Such defects adversely affect the final product. This paper proposes the in situ monitoring-based warpage prediction of metal AM products with experimental feature extraction. The temperature profile of the metal AM substrate during the process was experimentally collected. Time-domain features were extracted from the temperature profile, and their relationships to the warpage mechanism were investigated. The standard deviation showed a significant linear correlation with warpage. The findings from this study are expected to contribute to optimizing process parameters for metal AM warpage reduction.