• 제목/요약/키워드: Chang-Am

검색결과 337건 처리시간 0.025초

AM1 Studies on the Gas-Phase Pyrolysis of Iminoethers, 2-Alkoxypyridines, 2-N-Alkylated Pyridones and N-Alkylated Acetamides

  • Bon-Su Lee;Chang Kon Kim;Ikchoon Lee
    • Bulletin of the Korean Chemical Society
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    • 제12권5호
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    • pp.560-564
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    • 1991
  • The gas-phase pyrolysis reactions of iminoethers (Ⅱ), 2-alkoxypyridines (Ⅲ), 2-N-alkylated pyridones (Ⅳ) and N-alkylated acetamides (Ⅴ) have been studied MO theoretically with the AM1 method. The decomposition of these compounds proceeds by a concerted retro-ene process through a six-membered cyclic transition state. The reactivity decreases in the order (Ⅱ) > (Ⅲ) > (Ⅳ) > (Ⅴ), with a greater reactivity for the imine series, (Ⅱ) and (Ⅲ), compared to the amide series, (Ⅳ) and (Ⅴ), and a difference in basicity between the N and O atoms. Within a given series, however, the reactivity is dictated mainly by the aromaticity in the transition state. The reactivity order with respect to side alkyl chain of a species was found to increase as the steric crowding effect increases. The AM1 reactivity in this work agree well with the experimental results.

Novel Backplane for AM-OLED Device

  • Sung, Myeon-Chang;Lee, Ho-Nyun;Kim, Chang Nam;Kang, Sun Kil;Kim, Do Youl;Kim, Seong-Joong;Kim, Sang-Kyoon;Kim, Sung-Kab;Kim, Hong-Gyu;Kim, Sung-Tae
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.133-136
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    • 2007
  • IGZO TFTs were fabricated by conventional photolithography and wet-etching processes on metal substrates for the flexible display. The characteristics of TFTs on metal substrates were comparable to those of TFTs on glass substrates. Moreover, AM-OLED panels based on IGZO TFT arrays on metal substrates were successfully driven, for the first time.

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Properties of Indoor Particles Collected in Japanese Homes

  • Ma, Chang-Jin;Kang, Gong-Unn;Kang, Chang-Hee
    • Asian Journal of Atmospheric Environment
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    • 제9권1호
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    • pp.31-38
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    • 2015
  • Due to the heightened ambient $PM_{2.5}$ levels, the whole citizen of Japan, especially dwellers in Fukuoka Prefecture, start to make attention to the particulate matter (PM) of indoor environments. This study was aimed to thoroughly estimate the characteristics of indoor PM collected in five Japanese homes located in Fukuoka Prefecture. Simultaneous indoor measurements of PM were intensively made at five homes using filter-pack samplers, particle counters, and $PM_{2.5}$ monitors for a day in springtime, 2012. Major ionic and carbonaceous components were also analyzed. The time series fluctuation of PM number concentration was gradually decreased by 6 AM and then it was rapidly increased by 8 AM in all indoor sites. The maximum level of $PM_{2.5}$ was measured at the morning time (8 AM-9 AM) when the resident's behavior was fast and strenuous. The Indoor/Out-door (I/O) ratio for the giant PM larger than $5.0{\mu}m$ was 1.16. It was possible to identify PM types and estimate the resident's behavior through the comparison the theoretically calculated and the measured retention times for several types of PM in an indoor site. The theoretically reconstructed mass concentration of $PM_{2.0-0.3}$ suggested that the portion of $PM_{2.5}$ in indoor was quietly occupied by $PM_{0.3}$ or the PM inherently originated from indoor environment.

Camera Trapping of Long-Tailed Goral (Naemorhedus caudatus) in BaekAm and Geumjong Mountains, South Korea

  • Park, Hee Bok;Han, Chang Wook;Hong, Sungwon
    • Journal of Forest and Environmental Science
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    • 제34권1호
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    • pp.71-76
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    • 2018
  • The long-tailed goral (Naemorhedus caudatus) has slowly recolonized habitats in South Korea. Because it is necessary to know the status of groups in recolonized areas, we determined detection frequencies and group sizes using camera trapping, a non-invasive monitoring method. In Uljin, a far southern goral habitat in South Korea, we used a Moultrie 5.0 camera and mineral block as bait during the breeding season in BaekAm Mountain (148 days, 18 May to 11 October) and Geumjong Mountain (63 days, 18 May to 18 July) in 2010. Totally, 155 images were captured in BaekAm Mountain, whereas four images were captured in Geumjong Mountain. The species was most frequently detected at sunrise (05:00-08:00) and sunset (18:00-20:00). Through population structure evaluation, we identified at least 11 individuals, including one solitary mature male, four females, four kids, and two solitary subadults in BaekAm Mountain. However, in Geumjong Mountain, we identified only two individuals (female with kid). Monitoring efficiency in the recolonized area differed depending on population density and habitat conditions. Because we could evaluate the population structure, and behavioral patterns in the study sites, monitoring using camera traps could be applied for the recolonized habitats in South Korea.

Vapor-phase Oxidation of Alkylaromatics over V/TiO2 and VSb/Al2O3 Catalysts: Effect of Alkali Metals

  • Yoon, Ji-Woong;Jhung, Sung-Hwa;Chang, Jong-San
    • Bulletin of the Korean Chemical Society
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    • 제28권12호
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    • pp.2405-2408
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    • 2007
  • Oxidation of alkylaromatics including toluene and p-methoxytoluene has been carried out over alkali metal (AM)-containing catalysts such as AM-V/TiO2 and AM-VSb/Al2O3 in vapor-phase using oxygen as an oxidant. The selectivity for partial oxidations increases with incorporation of an alkali metal or with increasing the basicity of alkali metals (from Na to Cs), irrespective of the supports or reactants. However, the conversion is nearly constant or slightly decreasing with the addition of alkali metals in the catalyst. The increased selectivity may be related with the decreased acidity even though more detailed work is necessary to understand the effect of alkali metals in the oxidation. The AM-VSb/Al2O3 may be suggested as a potential selective catalyst for vapor-phase oxidations.

구창(口瘡)의 외용약(外用藥)으로 다용(多用)되는 황백(黃柏), 청대(靑黛), 백반(白礬) 및 오배자(五倍子)의 항염작용(抗炎作用)에 관한 연구(硏究) (The study on the anti-inflammatory effects of Phellodendri Cortex, Indigo Naturalis, Alumen, and Chinensis Galla, most frequently used for the external theraphy of Gu-Chang)

  • 최관호;김용국;강성구;정순영;정재호;서형식;유진곤
    • 한방안이비인후피부과학회지
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    • 제18권1호
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    • pp.183-198
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    • 2005
  • This experimental study was performed to investigate the anti-inflammatory effects of Phellodendri Cortex(PC), Indigo Naturalis(IN). Alumen(AM), and Chinensis Galla(CG). These four prescriptions most frequently have been used in of oriental medicine for the external the theraphy of Gu-Chang. This study was done to evaluate the activity of superoxide dismutase(SOD) and the inhibitory effects of the formation of cyclooxygenase-2(COX-2), tumor necrosis $factor-{\alpha}(TNF-{\alpha}),\;interlenkin-1{\beta}(IL-1{\beta})$, prostaglandin-E2(PGE2) on the monocyte and neutrophil. The results were summerized as follows. 1. IN has no cytotoxicity but PC, AM, CG have a little cytotoxicity by the increase of concentrations. 2. PC, IN, AM and CG all inhibited the formation of COX-2 in the human neutrophil. 3. $1000{\mu}g/m{\ell}$ of PC increased the formation of SOD in the human monocyte. 4. $1000{\mu}g/m{\ell}$ of PC, $100{\mu}g/m{\ell}$ and $1000{\mu}g/m{\ell}$ of IN, $100{\mu}g/m{\ell}$ of CG inhibited the formation of $TNF-{\alpha}$ in the human monocyte. 5. $10{\mu}g/m{\ell}$ of PC, $1000{\mu}g/m{\ell}$ of IN inhibited the formation of $IL-1\;{\beta}$ in the human monocyte. 6. PC, IN, AM and CG all did not inhibit the production of PGE2 in the human monocyte In addition, the results show that PC, IN, AM and CG all have anti-inflammatory effects and can be used fer the external theraphy of Cu-Chang.

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독도 해역의 해조자원

  • 최창근;전경암;홍병규;손철현
    • 한국양식학회:학술대회논문집
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    • 한국양식학회 2006년도 수산관련학회 공동학술대회 발표요지집
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    • pp.218-219
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    • 2006
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Developing an Embedded Method to Recognize Human Pilot Intentions In an Intelligent Cockpit Aids for the Pilot Decision Support System

  • 차우창
    • 대한인간공학회지
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    • 제17권3호
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    • pp.23-39
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    • 1998
  • Several recent aircraft accidents occurred due to goal conflicts between human and machine actors. To facilitate the management of the cockpit activities considering these observations. a computational aid. the Agenda Manager (AM) has been developed for use in simulated cockpit environments. It is important to know pilot intentions performing cockpit operations accurately to improve AM performance. Without accurate knowledge of pilot goals or intentions, the information from AM may lead to the wrong direction to the pilot who is using the information. To provide a reliable flight simulation environment regarding goal conflicts. a pilot goal communication method (GCM) was developed to facilitate accurate recognition of pilot goals. Embedded within AM, the GCM was used to recognize pilot goals and to declare them to the AM. Two approaches to the recognition of pilots goals were considered: (1) The use of an Automatic Speech Recognition (ASR) system to recognize overtly or explicitly declared pilot goals. and (2) inference of covertly or implicitly declared pilot goals via the use of an intent inferencing mechanism. The integrated mode of these two methods could overcome the covert goal mis-understanding by use of overt GCM. And also could it overcome workload concern with overt mode by the use of covert GCM. Through simulated flight environment experimentation with real pilot subjects, the proposed GCM has demonstrated its capability to recognize pilot intentions with a certain degree of accuracy and to handle incorrectly declared goals. and was validated in terms of subjective workload and pilot flight control performance. The GCM communicating pilot goals were implemented within the AM to provide a rich environment for the study of human-machine interactions in the supervisory control of complex dynamic systems.

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