Search results for "Connectivity"
showing 10 items of 246 documents
Savienojamības Problēmas Baltijas Jūras Reģionā. Fehmarn Belt Fixed Link Project un Øresund Bridge Gadījums
2021
Darbā tiek pētītas savienojamības problēmas Baltijas jūras reģionā, analizējot Fehmarn Belt Fixed Link un Øresund Bridge gadījumus. Savienojamības attīstība ir atkarīga no transporta koridoru harmonizācijas, modernizācijas un perspektīvas. Pētījums mērķis ir vērsts uz Fehmarn Belt Fixed Link ietekmes noteikšanu savienojuma elementiem. Izmantojot salīdzinošo metodi, tiek analizēti Øresund Bridge projekts un gaidāmā projekta kvalitatīvā SWOT analīze. Tiek pētīti Eiropas Savienības instrumenti, piemēram, Trans European Transport Network un Interreg, tādu reģionu savienojamībai kā Øresund, Skåne, Schleswig-Holstein un Zealand, transporta projektu rezultāti, termiņi un prognozes. Pētījums norāda…
Diversity and phylogeography of Southern Ocean sea stars (Asteroidea)
2019
How is life distributed on the Southern Ocean sea floor? How can we explain species distribution patterns, their origin and the underpinning drivers? These questions are central to macroecological studies, especially in regions facing fast environmental changes. The main objective of this thesis was to describe and characterise distribution patterns of sea stars species (Echinodermata: Asteroidea) with regards to reproductive strategy (i.e. brooding versus broadcasting), a key life history trait for species dispersal. I tested whether contrasting dispersal abilities between direct developers (brooders) and species with pelagic larvae in their development (broadcasters) result in distinct di…
Optimization of flat area coverage under connectivity constraint in wireless sensor networks
2022
A wireless sensor network consists of a set of small autonomous units that interact via a network built by their communication modules. They observe their environment, capture information, then manage this information according to their computing and/or storage capacity. To effectively accomplish their task(s), they need to cover as much of the area of interest as possible. It is therefore essential to quantify the quality of their coverage. In this thesis, we therefore seek to best cover an area of interest, with a precise number of sensors. While taking into account the possible overlaps between sensors, we first deploy in a zone of regular dimensions and evaluate the exact coverage using…
Where do recruits come from? Backward Lagrangian simulation for the deep water rose shrimps in the Central Mediterranean Sea
2022
Backward-in-time Lagrangian dispersion models can efficiently reconstruct drifters trajectories by linking known arrival positions to potential sources. This approach was applied to the deep water rose shrimp (Parapenaeus longirostris) in the Strait of Sicily (central Mediterranean Sea). The objective was to identify the potential spawning areas of the larvae that settle in the known nursery grounds of the northern sector of the Strait of Sicily, thus quantifying the extent of the potential contribution to recruitment from the surrounding regions. Numerical simulations were performed over 11 years (2005–2015) and for two different periods (spring/summer and autumn/winter) corresponding to t…
Noise influence on correlated activities in a modular neuronal network: From synapses to functional connectivity
2008
In this work we propose taking noise into account when modeling the neuronal activity in a correlation-based type network. Volume transmission effects on connectivity are considered. As a result, an individual module can be set in an "activated" state via noise produced by the remaining modules. The stochastic approach could provide a new insight into the relation between functional and anatomical connectivity.
Connectivity Influences on Nonlinear Dynamics in Weakly-Synchronized Networks: Insights from Rössler Systems, Electronic Chaotic Oscillators, Model a…
2019
Natural and engineered networks, such as interconnected neurons, ecological and social networks, coupled oscillators, wireless terminals and power loads, are characterized by an appreciable heterogeneity in the local connectivity around each node. For instance, in both elementary structures such as stars and complex graphs having scale-free topology, a minority of elements are linked to the rest of the network disproportionately strongly. While the effect of the arrangement of structural connections on the emergent synchronization pattern has been studied extensively, considerably less is known about its influence on the temporal dynamics unfolding within each node. Here, we present a compr…
Digitalizācijas process Eiropas Savienībā: Itālijas gadījums
2018
Digitalizācija ir izveidojusi ievērojami svarīgas pārmaiņas, kas Eiropas Savienībai un tās dalībvalstīm ir jāpieņem. Itālija tās digitālo procesu un prasmju vērtējumā ir zemāk par jebkuru citu ES dalībvalsti, tieši tāpēc šī situācija ir jāmaina un strauji jāuzlabo. Šī maģistra darba galvenais izvirzītais mērķis ir noteikt digitālizācijas svarīguma un ietekmes lomu Eiropā un Itālijā, lai atrastu iemeslus, kāpēc Itālija pēc šī kritērija ir viszemāk, salīdzinot ar pārējām ES dalībvalstīm, kā arī lai izdomātu un piedāvātu uzlabojumus Itālijas respondentu digitālajām prasmēm. Šī pētījuma rezultāts parāda, cik ES ir nepieciešami un svarīgi būt ne tikai digitālai, bet tikpat svarīga ir arī tās vēl…
Graph connectivity and monadic NP
2002
Ehrenfeucht games are a useful tool in proving that certain properties of finite structures are not expressible by formulas of a certain type. In this paper a new method is introduced that allows the extension of a local winning strategy for Duplicator, one of the two players in Ehrenfeucht games, to a global winning strategy. As an application it is shown that graph connectivity cannot be expressed by existential second-order formulas, where the second-order quantification is restricted to unary relations (monadic NP), even, in the presence of a built-in linear order. As a second application it is stated, that, on the other hand, the presence of a linear order increases the power of monadi…
Relations between structure and estimators in networks of dynamical systems
2011
The article main focus is on the identification of a graphical model from time series data associated with different interconnected entities. The time series are modeled as realizations of stochastic processes (representing nodes of a graph) linked together via transfer functions (representing the edges of the graph). Both the cases of non-causal and causal links are considered. By using only the measurements of the node outputs and without assuming any prior knowledge of the network topology, a method is provided to estimate the graph connectivity. In particular, it is proven that the method determines links to be present only between a node and its “kins”, where kins of a node consist of …
Graph Connectivity, Monadic NP and built-in relations of moderate degree
1995
It has been conjectured [FSV93] that an existential secondoder formula, in which the second-order quantification is restricted to unary relations (i.e. a Monadic NP formula), cannot express Graph Connectivity even in the presence of arbitrary built-in relations.