• Title/Summary/Keyword: strictly cyclic

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SOME REMARKS ON IRREDUCIBLE AUTOMATA AND PRIMITIVE SEMIGROUPS ASSOCIATED WITH THEM

  • Park, Chin-Hong;Shim, Hong-Tae
    • Journal of applied mathematics & informatics
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    • v.14 no.1_2
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    • pp.485-491
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    • 2004
  • We shall discuss irreducible and primitive S-automata. A variety of properties of transitive and primitive semigroups associated with them have been obtained. Also a classification of primitive semi groups will be given with S-automata.

SOME REMARKS ON S-SYSTEMS AND RADICAL ASSOCIATED WITH A SEMIGROUP S

  • Park, Chin-Hong
    • Journal of applied mathematics & informatics
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    • v.9 no.1
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    • pp.449-458
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    • 2002
  • We shall give a gereralization for a new right congruence induced by right congruences on S and right ideals of S and discuss the radicals associated with automata. Also we shall discuss the relationship between the collection of all right ideals in S and the collection of all right congruences on S.

TOXIC MECHANISM OF Ro09-0198 ISOLATED FROM STREPTOVERTICILLIUM (Ro 09-0198의 독성발현 기전에 관한 연구)

  • Choung, Se-Young
    • Toxicological Research
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    • v.6 no.1
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    • pp.109-119
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    • 1990
  • Ro09-0198, a cyclic peptide isolated from culture filtrates of Streptoverticillium griseoverticillatum, induced lysis of erythrocytes. Ro-09-0198-induced hemolysis was temperature-dependent and the sensitivity of hemolysis differed greatly among animal species. Preincubation of the peptide with phosphatidylethanolamine reduced the hemolytic activity, whereas other phospholipids present in erythrocytes in nature had no effect. A study of the structural requirements on phosphatidylethanolamine necessary for interaction with the peptide indicates that Ro09-0198 recognizes strictly a particular chemical structure of phosphatidylethanolamine: dialkylphosphoethanolamine as well as 1-acylglycerophosphoethanolamine showed the same inhibitory effct on hemolysis induced by Ro09-0198 as diacylphosphatidyl-ethanolamine, whereas phosphoethanolamine gave no inhibitory effect. Neither phosphatidyl-N-monomethylethanolamine nor alkylphosphopropanolamine had an inhibitory effect. Proton resonances of the peptide were observed in dimethyl sulfoxide solution in the presence of 1-dodecanoyl-sn-glycerophosphoethanolamine. This peptide caused permeability increase and aggregation of liposomes containing phosphatidylethanolamine. A glycerol backbone and a primary amino group of phosphatidylethanolamine are necessary for interaction with Ro09-0198 to cause membrane damage. Ro09-0198 induced a selective permeability change on liposomes. Glucose and umbelliferyl phosphate were effluxed significantly, but sucrose was only slightly permeable and inulin could not be released. Platelet aggregation and serotonin release simultaneously induced by Ro09-0198. Addition of peptide to rat platelet, loaded with the fluorescent $Ca^{++}$ chelator quin-2, caused immediate rise in cytosolic free $Ca^{++}$ to liposomal membrane containing phosphatidylethanolamine was observed dose dependently.

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New Generation of Lead Free Paste Development

  • Albrecht Hans Juergen;Trodler K. G.
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2004.09a
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    • pp.233-241
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    • 2004
  • A new alloy definition will be presented concerning increasing demands for the board level reliability of miniaturized interconnections. The damage mechanism for LFBGA components on different board finishes is not quite understood. Further demands from mobile phones are the drop test, characterizing interface performance of different package constructions in relation to decreased pad constructions and therefore interfaces. The paper discusses the characterization of interfaces based on SnPb, SnPbXYZ, SnAgCu and SnAgCuInNd ball materials and SnAgCuInNd as solder paste, the stability after accelerated tests and the description of modified interfaces strictly related to the assembly conditions, dissolution behavior of finishes on board side and the influence of intermetallic formation. The type of intermetallic as well as the quantity of intermetallics are observed, primaliry the hardness, E modules describing the ability of strain/stress compensation. First results of board level reliability are presented after TCT-40/+150. Improvement steps from the ball formulation will be discussed in conjunction to the implementation of lead free materials In order to optimize ball materials for area array devices accelareted aging conditions like TCTs were used to analyze the board level reliability of different ball materials for BGA, LFBGA, CSP, Flip Chip. The paper outlines lead-free ball analysis in comparison to conventional solder balls for BGA and chip size packages. The important points of interest are the description of processability related to existing ball attach procedures, requirements of interconnection properties and the knowledge gained the board level reliability. Both are the primary acceptance criteria for implementation. Knowledge about melting characteristic, surface tension depend on temperature and organic vehicles, wetting behavior, electrical conductivity, thermal conductivity, specific heat, mechanical strength, creep and relaxation properties, interactions to preferred finishes (minor impurities), intermetallic growth, content of IMC, brittleness depend on solved elements/IMC, fatigue resistance, damage mechanism, affinity against oxygen, reduction potential, decontamination efforts, endo-/exothermic reactions, diffusion properties related to finishes or bare materials, isothermal fatigue, thermo-cyclic fatigue, corrosion properties, lifetime prediction based on board level results, compatibility with rework/repair solders, rework temperatures of modified solders (Impurities, change in the melting point or range), compatibility to components and laminates.

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Declustering of High-dimensional Data by Cyclic Sliced Partitioning (주기적 편중 분할에 의한 다차원 데이터 디클러스터링)

  • Kim Hak-Cheol;Kim Tae-Wan;Li Ki-Joune
    • Journal of KIISE:Databases
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    • v.31 no.6
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    • pp.596-608
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    • 2004
  • A lot of work has been done to reduce disk access time in I/O intensive systems, which store and handle massive amount of data, by distributing data across multiple disks and accessing them in parallel. Most of the previous work has focused on an efficient mapping from a grid cell to a disk number on the assumption that data space is regular grid-like partitioned. Although we can achieve good performance for low-dimensional data by grid-like partitioning, its performance becomes degenerate as grows the dimension of data even with a good disk allocation scheme. This comes from the fact that they partition entire data space equally regardless of distribution ratio of data objects. Most of the data in high-dimensional space exist around the surface of space. For that reason, we propose a new declustering algorithm based on the partitioning scheme which partition data space from the surface. With an unbalanced partitioning scheme, several experimental results show that we can remarkably reduce the number of data blocks touched by a query as grows the dimension of data and a query size. In this paper, we propose disk allocation schemes based on the layout of the resultant data blocks after partitioning. To show the performance of the proposed algorithm, we have performed several experiments with different dimensional data and for a wide range of number of disks. Our proposed disk allocation method gives a performance within 10 additive disk accesses compared with strictly optimal allocation scheme. We compared our algorithm with Kronecker sequence based declustering algorithm, which is reported to be the best among the grid partition and mapping function based declustering algorithms. We can improve declustering performance up to 14 times as grows dimension of data.