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Coordination Patterns (coordination + pattern)
Selected AbstractsSeine: a dynamic geometry-based shared-space interaction framework for parallel scientific applicationsCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2006L. Zhang Abstract While large-scale parallel/distributed simulations are rapidly becoming critical research modalities in academia and industry, their efficient and scalable implementations continue to present many challenges. A key challenge is that the dynamic and complex communication/coordination required by these applications (dependent on the state of the phenomenon being modeled) are determined by the specific numerical formulation, the domain decomposition and/or sub-domain refinement algorithms used, etc. and are known only at runtime. This paper presents Seine, a dynamic geometry-based shared-space interaction framework for scientific applications. The framework provides the flexibility of shared-space-based models and supports extremely dynamic communication/coordination patterns, while still enabling scalable implementations. The design and prototype implementation of Seine are presented. Seine complements and can be used in conjunction with existing parallel programming systems such as MPI and OpenMP. An experimental evaluation using an adaptive multi-block oil-reservoir simulation is used to demonstrate the performance and scalability of applications using Seine. Copyright © 2006 John Wiley & Sons, Ltd. [source] Metal Ion Coordination to Azole NucleosidesCHEMISTRY - A EUROPEAN JOURNAL, Issue 21 2005Jens Müller Dr. Abstract To evaluate the possibility of introducing azole nucleosides as building blocks for metal-mediated base pairs in artificial oligonucleotides, imidazole nucleoside, 1,2,4-triazole nucleoside and tetrazole nucleoside have been synthesized and characterized. The X-ray crystal structures of p -toluoyl-protected 1,2,4-triazole and tetrazole nucleosides are reported. Contrary to the situation primarily found for deoxyribonucleosides, the sugar moieties adopt C3,- endo conformations. The acidity of the , nucleosides increases with increasing number of nitrogen ring atoms, giving pKa values of 6.01±0.05, 1.32±0.05 and <,3, respectively. This decrease in basicity results in a decreasing ability to form 2:1 complexes with linearly coordinating metal ions such as Ag+ and Hg2+. In all cases, the Ag+ complexes are of higher stability than the corresponding Hg2+ complexes. Whereas imidazole nucleoside forms highly stable 2:1 complexes with both metal ions (estimated log ,2 values of >10), only Ag+ is able to reach this coordination pattern in the case of triazole nucleoside (log ,2 = 4.3±0.1). Tetrazole nucleoside does not form 2:1 complexes at all under the experimental conditions used. These data suggest that imidazole nucleoside, and to a lesser extent 1,2,4-triazole nucleoside, are likely candidates for successful incorporation as ligands in oligonucleotides based on metal-mediated base pairs. DFT calculations further corroborate this idea, providing model complexes for such base pairs with glycosidic bond distances (10.8,11.0 Å) resembling those in idealized B-DNA (10.85 Å). [source] Spontaneous kicking in full-term and preterm infants with and without white matter disorderDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2010Linda Fetters Abstract Early damage to white matter of the brain may have developmental consequences for prematurely born infants including the coordination of leg movements. Our perspective is that white matter damage initiates an ontogenetic course that may lead to movement dysfunction leading to disability. In this study, spontaneous kicking in the human infant is a "window" for evaluating the potential consequences of perinatal brain damage for sensori-motor coordination. We compare the intra-limb coordination patterns of 5-month-old premature infants with white matter damage (PTWMD) to a group of prematurely born infants without WMD (PT) and a group of full-term (FT) infants. The PT group demonstrates advanced kicking patterns in comparison to both the PTWMD and FT groups. The PTWMD group has less mature patterns than the FT group on some, but not all measures. The movement challenge for PTWMD infants may be in the transition from spontaneous kicking to movements with the legs that require decoupling of intralimb joints. © 2010 Wiley Periodicals, Inc. Dev Psychobiol 52: 524,536, 2010. [source] Theoretical study of the microhydration of mononuclear and dinuclear uranium(VI) species derived from solvolysis of uranyl nitrate in waterJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 12 2010Milan On Abstract The structures and energetics of mononuclear and dinuclear uranium species formed upon speciation of uranyl(VI) nitrate, UO2(NO3)2, in water are investigated by quantum chemistry using density functional theory and the wavefunction-based methods (MP2, CCSD, CCSD(T)). We provide a discussion of the basic coordination patterns of the various mono- and dinuclear uranyl compounds [(UO2)m(X,Y)2m,1(H2O)n]+ (m = 1, 2; n = 0,4) found in a recent mass spectrometric study (Tsierkezos et al., Inorg Chem 2009, 48, 6287). The energetics of the complexation of the uranyl dication to the counterions OH, and NO3, as well as the degradation of the dinuclear species were studied by reference to a test set of 16 representative molecules with the MP2 method and the B3LYP, M06, M06-HF, and M06-2X DFT functionals. All DFT functionals provide structures and energetics close to MP2 results, with M06 family being slightly superior to the standard B3LYP functional. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010 [source] Comprehend and analyze knowledge networks to improve software evolutionJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 3 2009Christian Del Rosso Abstract When a set of people are connected by a set of meaningful social relationships we talk of a social network. A social network represents a social structure and the underlying structural patterns can be used to analyze and comprehend how people relate to each other and their emergent behavior as a group. Developing software is fundamentally a human activity. Developers cooperate and exchange knowledge and information, creating in fact, a particular type of social network that we call knowledge network. In this paper we investigate knowledge networks in software development teams by applying social network analysis and we use the Apache web server as a case study. By analyzing the structural communication and coordination patterns in Apache we have been able to identify the Apache knowledge network, highlight potential communication bottlenecks, and find brokers and important coordination points in the software development team. Furthermore, our work enables a software architect to analyze and maintain the organization and the software architecture aligned during software evolution. An important lesson that we have is that the analysis of knowledge networks constitutes an additional tool to be added to the traditional software architecture assessment methods. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||