• Title/Summary/Keyword: Bam

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Effects of the Characteristics of Precursor Powders and AlF3 Flux on the Properties of Blue-Emitting BAM:Eu Phosphor Powders (전구체의 특성 및 AlF3 융제가 청색 발광의 BAM:Eu 형광체의 특성에 미치는 영향)

  • Cho, Jung-Sang;Lee, Sang-Ho;Kang, Yun-Chan
    • Korean Journal of Materials Research
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    • v.18 no.3
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    • pp.137-142
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    • 2008
  • Blue-emitting BAM:Eu phosphor powders were formed by post-treatment of precursor powders with hollow or dense morphologies. The morphologies of the precursor powders obtained by spray pyrolysis were controlled by changing the preparation conditions and by changing the type of spray solution. The effects of the morphologies of the precursor powders on the characteristics of the BAM : Eu phosphor powders reacted with $AlF_3$ flux were investigated. Precursor powders with a spherical shape and a hollow morphology produced BAM : Eu phosphor powders with a plate-like morphology, a fine size and a narrow size distribution. On the other hand, precursor powders with a spherical shape and dense morphology produced BAM : Eu phosphor powders with a plate-like morphology and a large size. $AlF_3$ flux improved the photoluminescence intensities of the BAM : Eu phosphor powders. The photoluminescence intensity of the fine-sized BAM : Eu phosphor powders with a plate-like morphology was 90% of the commercial product under vacuum ultraviolet conditions.

Synthesis and Characterization of Comb-Type Grafted Polymer Hydrogels with Low Temperature Sensitivity (저온 감열 특성을 가지는 Comb-Type Grafted Polymer Hydrogels의 합성 및 특성평가)

  • Taek Kyu Jung;Sung Soo Kim;Byung Cheol Shin
    • Journal of the Korean Chemical Society
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    • v.47 no.1
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    • pp.59-66
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    • 2003
  • The comb-type grafted polymer hydrogels, which composed of N-isopropylacrylamide monomer and oligo(N-isopropylacrylamide-co-tert-butylacrylamide) [oligo(NIPAAm-co-t-BAM)], were synthesized by redox polymerization in 5~10% methanol aqueous solution using ammonium peroxodisulfate (APS) at 4 oC for 24h. The lower critical solution temperatures (LCSTs) of the comb-type grafted hydrogels were decreased with increase of t-BAM content in the grafted copolymer. We observed the effect of crosslinker and concentration of oligo(NIPAAm-co-t-BAM) on the shrinking/swelling ratio of hydrogels. Changes of shrinking/swelling ratio were decreased with increase of concentration of crosslinker. The increase of grafted oligo(NIPAAm-co-t-BAM) in the hydrogel shows an fast changes of shrinking/ swelling rate. The comb-type grafted hydrogels are expected to be valuable for the sensing materials of time-temperature labels(TTLs).

Design of BAM using an Optimization approach (최적화기법을 이용한 BAM의 설계)

  • 권철희
    • Journal of the Korean Institute of Intelligent Systems
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    • v.10 no.2
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    • pp.161-167
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    • 2000
  • In this paper, we propose a design method for BAMs(bidirectiona1 associative memories) which can perform the function of bidirectional association efficiently. Based on the theoretical investigation about the properties of BAMs, we first formulate the problem of finding a BAM that can store the given pattern pairs as stable states with high error correction ratio in the form of a constrained optimization problem. Next, we transform the constrained optimization problem into a GEVP(genera1ized eigenvalue problem), which can be solved by recently developed interior point methods. The applicability of the proposed method is illustrated via design examples.

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Face Alignment using Template Warping BAM (템플릿 워핑 BAM을 이용한 얼굴 윤곽선 검출)

  • Kim, Seok-Ho;Kim, Jae-Min;Cho, Seoung-Won;Lee, Ki-Sung;Chung, Sun-Tae
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2008.04a
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    • pp.418-420
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    • 2008
  • 얼굴 윤곽선 검출을 위해 그동안 많은 알고리즘이 연구되었다. 그리고 최근에 기존 Active Appearance Model(AAM)에 비해 성능이 개선된 Boosted Appearance Model (BAM)가 Liu에 의해제안되었다. BAM에서는 매 반복 단계마다 Steepest Descent 영상을 구해야 하는데 입력영상의 워핑을 해야 하므로 이것은 계산량이 많다. 본 논문은 BAM을 사용하면서 매번 계산되어야 하는 입력 영상의 워핑을 대신해 템플릿이 워핑함으로써 계산 시간을 줄일 수 있는 방법을 제시한다. 템플릿은 약한 분류기에 사용되는 Haar-like feature들로 이것은 입력 영상에 비해 크기가 매우 작으므로 제안된 방법을 사용하면 Steepest Descent 영상을 구하는데 필요한 워핑 속도를 줄일 수 있다.

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Sensory and Physical Characteristics of Bam-dduk Prepared with Different Ratio of the Ingredients (재료배합비를 달리한 밤떡의 관능적 및 물리적 특성)

  • 김지영;차경희;이효지
    • Korean journal of food and cookery science
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    • v.13 no.4
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    • pp.427-433
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    • 1997
  • Various Bam-dduk were prepared by using two kinds of chestnut flour (dried chestnut, boiled chestnut), 2 types of sugar (sugar and honey), and 3 levels of sugar (10, 20, 30 g), and they were evaluated for sensory quality, texture, moisture, and color. The addition of 10∼15% of dried chestnut flour to glutinous rice flour increased the graininess, moistness, chewiness, and sweetness of Bam-dduk, and the addition of 30∼40% boiled chestnut flour increased the graininess, moistness, and sweetness, depending up on the types and levels of sugar. The use of 10% dried chestnut flour and 30 $m\ell$ of honey gave the highest value of springiness in Bam-dduk. Gumminess, hardness and chewiness were the highest with 15% dried chestnut flour and 20 g sugar. Cohesiveness was the strongest at 30% boiled chestnut flour and 10 $m\ell$ honey. Adhesiveness was most proper when 30 g sugar was added to 10% dried chestnut flour. The use of boiled chestnut flour gave higher moisture content in Bam-dduk (32.2∼41.3%) than the use of dried chestnut flour (29.6∼34.2%). The values of 'L' (67.43) and 'b' (18.07) were most intensive in Bam-ddfik prepared with 15% dried chestnut and 20 g sugar, and the replacement of 20 g sugar with 30 $m\ell$ of honey gave the highest 'a' value, 2.33.

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Cloning of the rbcL Gene from Maize Chloroplast (옥수수 엽록체 rbcL 유전자의 클로닝)

  • 이재선
    • Journal of Plant Biology
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    • v.35 no.2
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    • pp.165-171
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    • 1992
  • In order to study regulation of rbcL gene expression, rbcL gene of chloroplast DNA (Cp DNA) from maize was cloned. Cp DNA was isolated from intact chloroplast and digested with BamHI. BamHI 9 fragment of Cp DNA containing rbcL gene was ligated to pUC19 and transformed into E. coli DH5a. This recombinant plasmid was named pRLYSl. pRLYSl was hybridized with a part of rbcL gene from rice and digested with restriction enzyme BamHI, HindIIl, and PstI. From these results, it was confirmed that pRLYS1 contains intact rbcL gene and orientation of BamHI 9 fragment of Cp DNA in pRLYS1 was determined.rmined.

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Cloning and Idendification of dTDP-L-Rhamnose Biosynthetic Gene Cluster from Thermus caldophilus GK24

  • Kim, Ki-Chan;Lee, Seung-Don;Han, Ju-Hee;Sohng, Jae-Kyung;Liou, Kwang-Kyoung
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.749-754
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    • 2000
  • PCR primers were designed based on consensus sequences of dTDP-D-glucose 4,6-dehydratase, one of the enzymes involved in the biosynthesis of deoxysugar. The PCR product (360 bp) was obtained from Thermus caldophilus GK24. Colony hybridization was carried out to the cosmid library constructed from T. caldophilus GK24 genomic DNA by the PCR product DNA fragment. We isolated a cosmid clone (pSMTC-1) that was subcloned to call pKCB series plasmid (BamHI fragments), partially sequenced and analyzed. pKCB80 (4.2 kb-BamHI DNA fragment) of them showed ORFs that was orfA, orfB, orfC and orfD. The orfABCD gene cluster is the deosysugar biosynthetic gene ; orfA (glucose-1-phosphate thymidylytransferase), orfB (dTDP-D-glucose 4,6-dehydratase), orfC (dTDP-4-keto-L-rhamnose reductase) and orfD (dTDP-4-keto-6-deoxy-D-glucose 3,5-epimerase). The gene cluster that was related in biosynthesis of dTDP-L-rhamnose was also identified by computer analysis, and we proposed that the biosynthetic pathway of deoxysugar analyzed from DNA sequencing of pKCB80 is from D-glucose-1-phosphate, dTDP-D-glucose, dTDP-4-keto-6-deoxy-D-glucose via dTDP-4-keto-L-rhamnose to dTDP-L-rhamnose.

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Alteration of Recognition Sequence by Restriction Endonuclease -Effect of pH and Hydrophobicity on BamHI- (제한효소의 인식자리 변화 -BamHI 특이성에 미치는 산도와 소수성의 영향-)

  • 이강민
    • KSBB Journal
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    • v.11 no.2
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    • pp.193-200
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    • 1996
  • In molecular biology, type-II restriction endonuclease, which specifically recognize and cleave DNA at a limited number of sites, have been exploited as a means of characterizing DNA fragments, DNA mapping for genetic engineering. Type-II restriction endonucleases have been found to modulate their substrate specificity under modified conditions such as extreme pH, ionic strength, high enzyme concentration, substitution of metallic cofactors or addition of organic solvents. This study was initiated to investigate the modification of recognition specificity of BamHI according to the different pH and organic solvent under the given buffer condition. The specificity of BamHI is highly depends on the presence of hydrophobicity (LogP: partition coefficient) and pH of reaction solution. The specificity of BamHI is changed in range of LogP -1.03∼-1.35(at pH 7.5), -1.03∼-2.5 (at pH 8.0), -0.75∼-0.25(at pH 8.5), 0.32∼-2.5(at pH 8.9), respectively. Alteration of specificity appears in lower concentration of organic solvent when the reaction occurs in more alkali pH. For example, in DMSO solution, alteration of specificity appears in 20% concentration at pH 7.5 but in 4% concentration at pH 8.9.

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Frankia sp. strain SNU 014201의 nif-H, D, K, 유전자 클로닝

  • 권석윤;강명수;안정선
    • Korean Journal of Microbiology
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    • v.30 no.1
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    • pp.30-36
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    • 1992
  • nif (nitrogen fixation)-H.D, K genes of Frankia sp. SNU 014201. a symbiotic strain isolated from root nodule of Alnus hirsura, were found to be located in the genome on 13.5 kb of EcoRI, 18.0 kb of BamHI, 10.5 kb of BglII and 4.5 kb of KpnI fragments. Using EMBL-3 BamHI arms of bacteriophage lambda. the genomic library was constructed. from which fourteen recombinant phage nif-clones were selected. Among them, Ahnif-I2 had insert DNA of 18 kb, in which 7.9 kb of BamHl fragment contained nif-H, D, K and 3.6 kb of HindlIl/KpnI had nif-H and partial -D. Therefore, the 7.9 kb and 3.6 kb fragments were subcloned and partial restriction maps were constructed. As the results, nif-F1, D.K genes were found to be located continuously on the 6.5 kb of HindII/BamHI and 5.2 kb of SalIIBamHI fragment in the genome of Frankia sp. SNU 014201.

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Comparison of the PM10 Concentration in Different Measurement Methods at Gosan Site in Jeju Island (제주도 고산 측정소의 미세먼지 측정방법에 따른 질량농도 비교)

  • Shin, So-Eun;Kim, Yong-Pyo;Kang, Chang-Hee
    • Journal of Environmental Impact Assessment
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    • v.19 no.4
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    • pp.421-429
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    • 2010
  • The reliability of the measurement of ambient trace species is an important issue, especially, in background area such as Gosan in Jeju Island. In a previous episodic study, it was suggested that the PM10 measurement result by the gravimetric method(GMM) was not in agreement with the result by the ${\beta}$-ray absorption method(BAM). In this study, a systematic comparison was carried out for the data between 2001 and 2008 at Gosan(GMM and BAM) and Jeju city (BAM) which is near to Gosan. It was found that at Gosan the PM10 concentration by BAM was higher than GMM and the correlation between them was low. The BAM results at Gosan and Jeju city showed similar trend implying the discrepancy at Gosan was not caused by instrumental problem of the BAM at Gosan. Based on the previous studies two probable reasons for the discrepancy are identified; (1) negative measurement error by the evaporation of volatile ambient species at the filter in GMM such as nitrate and ammonium and (2) positive error by the absorption of water vapor during measurement in BAM. There was no heater at the inlet of BAM at Gosan during the sampling period. Based on the size-segregated measurement data, it was identified that the evaporation error was minor, if any. The relationship between the two methods did not vary with the ambient relative humidity. Thus, at present, it is not clear why the discrepancy had been occurring and when using the PM10 data at Gosan, one should be aware the possible errors.