• 제목/요약/키워드: a:b

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BINDING NUMBER CONDITIONS FOR (a, b, k)-CRITICAL GRAPHS

  • Zhou, Sizhong
    • 대한수학회보
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    • 제45권1호
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    • pp.53-57
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    • 2008
  • Let G be a graph, and let a, b, k be integers with $0{\leq}a{\leq}b,k\geq0$. Then graph G is called an (a, b, k)-critical graph if after deleting any k vertices of G the remaining graph of G has an [a, b]-factor. In this paper, the relationship between binding number bind(G) and (a, b, k)-critical graph is discussed, and a binding number condition for a graph to be (a, b, k)-critical is given.

은행나무의 몇가지 다형적(多形的) 동위효소(同位酵素)의 유전양식(遺傳樣式) 및 연관(連關) (Inheritance and Linkage of Some Polymorphic Isozymes in Ginkgo biloba L.)

  • 권해연;김진수
    • 한국산림과학회지
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    • 제89권4호
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    • pp.527-535
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    • 2000
  • 감자전분젤을 매개로 한 수평식 전기영동장치를 이용하여 은행나무(Ginkgo biloba L.)의 megagametophyte로부터 15개 동위효소의 변이가 분석되었다. 분석된 효소 가운데서 ADH, G6PD, IDH, MPI, UGPP의 5개 효소에서는 변이가 나타나지 않았으며, 나머지 10개 효소의 11개 동위효소 구역(ACON-A, FST-B, GDH-A, GOT-B, MDH-B, MDH-C, MNR-A, PGI-B, PGM-A, 6PGD-B, SKDH-B)에서 다형성이 관찰되었다. 이중 MDH-B를 제외한 모든 구역에서 관찰된 동위효소 변이들이 1 : 1의 독립적 분리비를 보임으로써, 이들이 단일 유전자좌에 의해 조절되는 공우성 대립유전자임을 추정할 수 있었다. 한편, 동위효소 유전자좌의 3가지 조합(ACON-A : MDH-B, GOT-B : PGI-B, MNR-A : SKDH-B)에서 약한 연관관계가 관찰되었으며, 이들의 재조합 비율은 0.38-0.40로 계산되었다 (p<0.05).

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Lactobacillus casei Bacperiophage의 분류 및 특성에 관한 연구 (Classification and Characterization of Bacteriophages of Lectobacillus casei)

  • 김영창;박민철;강국희;윤영호;이광웅
    • 미생물학회지
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    • 제17권4호
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    • pp.165-178
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    • 1979
  • Phages of Lactobaciilus casei (PLC) isolated from plant drainage were classified and characterized. The results are as follows : 1. On the basis of host range pattern, phages could be divided into 2 groups (PLC-B and PLC-C). PLC-B group phages could be further divided into 5 sub-groups $(B_1, \;B_2, \;B_3, \;B_4, \;and\;B_5)$. Although PLC-C group phages had the same host range, they could be also divided into 2 sub-groups $(C_1\;and\;C_2)$ by morphlogical type. 2. It was $B_3$ group phages that represented a major proportion (44.4%) of phages tested. However, $B_1$ group phages were shown to have the widest host range. 3. Electron micrographs revealed that the phages fell into three different morphological types. $(B_1, \;B_2, \;and\;B_3)$ group phages hd a hexagonal head (52nm in diameter) and a sheathless noncontractile (245 nm in length). $B_4\;and\;C_2$ group phages had a hexagonal head (56 nm) and a short flexible tail (169nm) having no sheath. $B_5\;and\;C_1$ group phages were shown to have a hexagonal head (81 nm) and a contractile tail (140 nm) having a sheath, a base plate and tail fibers. 4. The inactivation of the phages by antisera indicated that serological relationships correlated completely with morphological types. 5. $B_1, \;C_1\;and\;C_2$ group phages produced a large (1, 2 mm in diameter) plaque with a clear ring. The morphology of plaques of $B_3\;and\;B_5$ group phages was the same as those produced by the above, but the average plaque sizes for $B_3\;and\;B_5$ were 0.8 mm abd 0.5 mm, respectively. $B_2\;and\;B_4$ group phages produced a small (0.5 mm) turbid plaque with an irregular edge. 6. The latent period and the average burst size of $B_1\;and\;B_3$ group phages were 90 min and 100, respectively. These phages reuqired calcium ions for their miltiplication. 7. $B_3$ group phages could not be absrobed to R-variant $KC_1$. 8. The order of resistance of phages to heat was $B_2\;>\;B_1, B_4\;and\;B_5\;>\;B_3\;and\;C_2, \;B_5$ group phages were more stable than $B_3$ in various pH values. $C_2$ group phages were more sensitive to UV irradiation than $B_1\;and\;B_3$ group phages. 9. Strains YIT9018 and IAM 1043 were induced by mitomycin C treatment. Phage particles detected in the lysates had a hexagonal head (38 and 49 nm, respectively), but no tail. Any sensitive indicator strain could not be isolated in spite of repaeated trials.

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PROPERTIES OF GENERALIZED BIPRODUCT HOPF ALGEBRAS

  • Park, Junseok;Kim, Wansoon
    • 충청수학회지
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    • 제23권2호
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    • pp.323-333
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    • 2010
  • The biproduct bialgebra has been generalized to generalized biproduct bialgebra $B{\times}^L_H\;D$ in [5]. Let (D, B) be an admissible pair and let D be a bialgebra. We show that if generalized biproduct bialgebra $B{\times}^L_H\;D$ is a Hopf algebra with antipode s, then D is a Hopf algebra and the identity $id_B$ has an inverse in the convolution algebra $Hom_k$(B, B). We show that if D is a Hopf algebra with antipode $s_D$ and $s_B$ in $Hom_k$(B, B) is an inverse of $id_B$ then $B{\times}^L_H\;D$ is a Hopf algebra with antipode s described by $s(b{\times}^L_H\;d)={\Sigma}(1_B{\times}^L_H\;s_D(b_{-1}{\cdot}d))(s_B(b_0){\times}^L_H\;1_D)$. We show that the mapping system $B{\leftrightarrows}^{{\Pi}_B}_{j_B}\;B{\times}^L_H\;D{\rightleftarrows}^{{\pi}_D}_{i_D}\;D$ (where $j_B$ and $i_D$ are the canonical inclusions, ${\Pi}_B$ and ${\pi}_D$ are the canonical coalgebra projections) characterizes $B{\times}^L_H\;D$. These generalize the corresponding results in [6].

One-step Synthesis of Supramolecular Rectangles Starting from ($\eta^5$-Pentamethylcyclopentadienyl)rhodium(III) Aqua Complex

  • 한원석;이순원
    • 한국결정학회:학술대회논문집
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    • 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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    • pp.27-27
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    • 2002
  • [Cp*Rh(H₂O)₃](OTf)₂ (1) reacts with a stoichiometric amount of A and B [ A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)] in acetone at room temperature for 3 h to give the supramolecular complexes [Cp*₄Rh₄(μ-A)₄(μ-B)₂] [A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)]. Complexes 2a and 2b have been structurally characterized by X-ray diffraction.

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1,4-Dicyanobutene Bridged Binuclear Iridium (I, III) Complexes and Their Catalytic Activities

  • Park, Hwa-Kun;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • 제8권3호
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    • pp.185-189
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    • 1987
  • Reactions of $Ir(ClO)_4(CO)(PPh_3)_2$ with dicyano olefins, cis-NCCH = CH$CH_2$$CH_2$CN (cDC1B), trans-NCCH = CH$CH_2$$CH_2$CN (tDC1B), trans-NC$CH_2$CH = CH$CH_2$CN (tDC2B), and NC$CH_2$$CH_2$$CH_2$$CH_2$CN (DCB) produce binuclear dicationic iridium (I) complexes, $[(CO)(PPh_3)_2Ir-NC-A-CN-Ir(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (1a), tDC1B (1b), tDC2B (1c), DCB (1d)). Complexes 1a-1d react with hydrogen to give binuclear dicationic tetrahydrido iridium (Ⅲ ) complexes, $[(CO)(PPh_3)_2(H)_2Ir-NC-A-CN-Ir(H)_2(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (2a), tDC1B (2b), tDC2B (2c), DCB (2d)). Complexes 2a and 2b catalyze the hydrogenation of cDC1B and tDC1B, respectively to give DCB, while the complex 2c is catalytically active for the isomerization of tDC2B to give cDC1B and tDC1B and the hydrogenation of tDC2B to give DCB at $100^{\circ}C$.

ON LOCALLY B*- EQUIV ALENT ALGEBRAS

  • Kang, Soon-Ja
    • 호남수학학술지
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    • 제4권1호
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    • pp.167-172
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    • 1982
  • Let A be a Banach $^{\ast}$-algebra and C(t) be a closed $^{\ast}$-subalgebra of A gengerated by $t{\in}A$. A is locally $B^{\ast}$-equivalent [$B^{\ast}$-equivalent] if C(t) [A] for every hermitian element t is $^{\ast}$-isomorphic to some $B^{\ast}$-algebra. It was proved that the locally $B^{\ast}$-equivalent algebras with some conditions is $B^{\ast}$-equivalent by B. A. Barnes. In this paper, we obtain the some conditions for a locally $B^{\ast}$-equivalent algebra to be $B^{\ast}$-equivalent.

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소음노출량측정기의 Set Up 방법간의 시간가중평균값(TWA)의 차이 (Difference of Time Weighted Averages in Different Setting Ups for Noise Dosimeter)

  • 양흥석;이광묵;원정일
    • 한국산업보건학회지
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    • 제5권2호
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    • pp.193-199
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    • 1995
  • This study was designed to investigate the difference of time weighted average(TWA) of noise levels and noise doses by the different operating parameter settings such as exchange rate, threshold level and criterion level for noise dosimeter in the field measurements of noise at industrial working environments. The time weighted averages of noise level and noise doses for noise working environments were determined by noise dosimeter on 80 workers employed at 20 industrial establishments of 8 industries. The results obtained were as follows: 1. The mean time weighted average(TWA) of the noise working environments by the operating parameter settings showed 93.4 dB(A) in 3 dB of exchange rate, 80 dB of threshold level and 90dB of criterion level 92.0 dB(A) in 3 dB-exchange rate, 90 dB-threshold level and 90 dB-criterion level, in 90.8 dB(A) in 5 dB of exchange rate, 80 dB of threshold level and 90 dB of criterion level, and 86.7 dB(A) in 5 dB of exchange rate, 90 dB of threshold level and 90dB of criterion level. 2. ln group of noise level less than 90 dB(A), mean TWAs of 80 dB of threshold level were significantly higher than that of 90 dB of threshold level in 3 dB and 5 dB of exchange rate. 3. The case exceeded threshold limit value of noise was 49(61.3 %) in 3dB, 80dB and 90 dB setting, 44(55.0 %) in 3 dB, 90 dB, 90 dB setting, 33(41.3 %) in 5 dB, 80dB, 90 dB setting and 26(32.5%) in 5 dB, 90 dB, 90 dB setting. Above considerations in mind, it is suggested that exchange rate and threshold level be specified in related laws and regulations in the evaluation of working environments noise.

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B2B 워크플로우의 메시징 시스템 설계 (Design of a Messaging System for B2B Workflow)

  • 서창교;김정삼;이형석
    • Asia pacific journal of information systems
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    • 제11권1호
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    • pp.117-137
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    • 2001
  • B2B(business-to-business) commerce has become the prime driver of contemporary electronic commerce. Under B2B commerce, corporations often must operate across organizational boundaries to share their business processes. Workflow management was proposed by Aalst(4, 5) to support several business partners that are involved in shared workflow processes in B2B commerce. We designed a messaging system for B2B workflow, where heterogeneous workflow management systems on each organization for trade were integrated. Based on Aalst's example in(4, 5), we analyzed B2B workflow by using class diagram, use case diagram, activity diagram, and statechart diagram of UML, and designed the messaging system, We also demonstrated a prototype system which was implemented by using Java API and XML. To compare with a holistic system such as EDI systems, the messaging system allows the business partners in B2B commerce to communicate with each other by dedicated messages and integrate each B2B interoperable workflow without any restrictions.

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삼국시대 원추형 수식에 대한 연구 (A Study on the Cone Shaped Pendants in the Period of the Three States)

  • 김문자
    • 복식문화연구
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    • 제10권5호
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    • pp.485-492
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    • 2002
  • The purpose of this study is to classify of the Cone shaped Pendants in old tombs of Three Kingdom States. These Cone shaped Pendants are made of bronze and coated with gold plate or Gold. Each Cone shaped Pendants consists of a Sehwhan(細環) type or Taewhan type, a median part in the form of a several joined small globe, or circular shape, and finally a cone-shared pendant. Cone shaped Pendants is 5 part(A-L A-b, B-1-a, B-1-b, B-2-b type) in according to the styles of the Sehwhan(細環) and Taewhan type and median ornament types. A-a, A-b, B-1-a, B-1-b type was general style that was found in most of the old tombs in Kokuryo, Pacjae, ancient Silla. B-2-b type was excavated from the only Kokuryo tombs.

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