PIM-SM extension for Source-Specific Multicast through non multicast networks

Barneko ikerkuntza-txostena

D3M: multicast listener mobility support mechanisms over distributed mobility anchoring architectures

The explosion in mobile data traffic is a driver for future network operator technologies, given its large potential to affect both network performance and generated revenue. The concept of distributed mobility management (DMM) has emerged in order to overcome efficiency-wise limitations in centralized mobility approaches, proposing not only the distribution of anchoring functions but also dynamic mobility activation sensitive to the applications needs. Nevertheless, there is not an acceptable solution for IP multicast in DMM environments, as the first proposals based on MLD Proxy are prone to tunnel replication problem or service disruption. We propose the application of PIM-SM in mobility entities as an alternative solution for multicast support in DMM, and introduce an architecture enabling mobile multicast listeners support over distributed anchoring frameworks in a network-efficient way. The architecture aims at providing operators with flexible options to provide multicast mobility, supporting three modes: the first one introduces basic IP multicast support in DMM; the second improves subscription time through extensions to the mobility protocol, obliterating the dependence on MLD protocol; and the third enables fast listener mobility by avoiding potentially slow multicast tree convergence latency in larger infrastructures, by benefiting from mobility tunnels. The different modes were evaluated by mathematical analysis regarding disruption time and packet loss during handoff against several parameters, total and tunneling packet delivery cost, and regarding packet and signaling overhead.

A point interpolation method with locally smoothed strain field (PIM-LS2) for mechanics problems using triangular mesh

A point interpolation method with locally smoothed strain field (PIM-LS2) is developed for mechanics problems using a triangular background mesh. In the PIM-LS2, the strain within each sub-cell of a nodal domain is assumed to be the average strain over the adjacent sub-cells of the neighboring element sharing the same field node. We prove theoretically that the energy norm of the smoothed strain field in PIM-LS2 is equivalent to that of the compatible strain field, and then prove that the solution of the PIM- LS2 converges to the exact solution of the original strong form. Furthermore, the softening effects of PIM-LS2 to system and the effects of the number of sub-cells that participated in the smoothing operation on the convergence of PIM-LS2 are investigated. Intensive numerical studies verify the convergence, softening effects and bound properties of the PIM-LS2, and show that the very ‘‘tight’’ lower and upper bound solutions can be obtained using PIM-LS2.

The effects of low degree alteration on Sm-Nd and U-Pb isotope systematics in Eoarchean basalts from the Doolena Gap and Warralong Greenstone belts, Pilbara Craton, Western Australia

This research led to the discovery of one of the best preserved remnants of the Earth's surficial environment 3.47 billion years ago. These ancient volcanic and sedimentary rocks contain original minerals and textures that are rare in rocks of this age. The research concentrated on chemical analysis of volcanic rocks to differentiate secondary alteration from the primary magmatic signature. This study contributes to our understanding of melting processes and geochemical reservoirs in the early Earth, which is vital for forward modelling of Earth's geodynamic evolution.

A meshless method based on Point Interpolation Method (PIM) for the space fractional diffusion equation

This paper aims to develop a meshless approach based on the Point Interpolation Method (PIM) for numerical simulation of a space fractional diffusion equation. Two fully-discrete schemes for the one-dimensional space fractional diffusion equation are obtained by using the PIM and the strong-forms of the space diffusion equation. Numerical examples with different nodal distributions are studied to validate and investigate the accuracy and efficiency of the newly developed meshless approach.

Samarbete mellan konkurrenter - en undersökning av österbottniska sm-företag

Under senare tid har förekomsten av samarbete mellan konkurrerande sm-företag ökat. Forskningen kring ämnet har dock bedrivits i mindre skala, framför allt om man beaktar finländska (nordiska) förhållanden. Syftet med denna undersökning är att kartlägga förekomsten av samarbete mellan konkurrerande sm-företag i Österbotten (Finland), samt beskriva dessa. Gällande demografiska variabler jämförs dessa företag även med sm-företag som inte samarbetar. Data insamlades genom en enkät utskickad i november 2001 till 345 sm-företag i Österbotten. Svarsprocenten var 35.1. Av de respondenter som besvarade enkäten, var 47.9 procent involverade i ett eller flera samarbeten med ett eller flera företag som var deras konkurrenter. Samarbete mellan konkurrenter är således inte ett ovanligt fenomen, utan innefattar allt från informella, operativa samarbeten till formella, strategiskt viktiga samarbeten. Samarbete inom produktion var den mest vanligt förekommande formen av samarbete. Partnern kom från Finland, även om målmarknaderna för samarbetet fanns både i Finland och i utlandet. Denna undersökning kunde inte identifiera någon större skillnad mellan de sm-företag som samarbetade med konkurrenter och de sm-företag som inte samarbetade. Det intressanta är således att det inte verkar finnas några skillnader vad gäller ålder, omsättning, omsättningsökning, underleverans- och exportverksamhet mellan de samarbetande och de icke samarbetande företagen. Skillnaderna bör således sökas i andra variabler. Den enda signifikanta skillnaden kunde upptäckas i upplevelsen av konkurrens. Tidigare forskning har identifierat att osäkerhet i konkurrensen är ett incitament till att börja samarbeta med konkurrenter. Denna undersökning förstärker detta antagande. De samarbetande företagen upplevde att konkurrensen var hårdare än de icke samarbetande företagen. Bland de samarbetande företagen var det speciellt de mindre (med en personalstyrka mellan 10 och 50 arbetstagare) som upplevde att konkurrensen var hård. Undersökningen har finansierats med stipendiemedel från Sparbanksstiftelsen i Vasa och Handlande Gustav Svanljungs fond.

In vitro meristem cloning of Eucalyptus tereticornis Sm

Rapid multiplication of axillary meristems and direct shoot development occurred from nodal explants of mature Eucalyptus tereticornis Sm. with 5.3 mgrM NAA, 1.1 mgrM IAA and 4.4 mgrM BA in Murashige-Skoog medium. Repeated subcultures of the second generation shoot cultures into low cytokinin-auxin containing media (0.44�0.88 mgrM BA+0.1 mgrM NAA) yielded axillary microshoots in large numbers. Half-strength MS liquid medium with 4.9 mgrM IBA, 5.5 mgrM IAA and 5.3 mgrM NAA for four days, half-strength semi-solid hormonefree MS medium with charcoal, and MS liquid medium without charcoal and hormones, in sequence, induced rooting of shoots in the dark. This system is suitable for the mass propagation of this difficult-to-root eucalypt.