his.sePublikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Generating Structure Specific Networks
Högskolan i Skövde, Forskningscentrum för Systembiologi. Högskolan i Skövde, Institutionen för vård och natur.
Högskolan i Skövde, Forskningscentrum för Systembiologi. Högskolan i Skövde, Institutionen för vård och natur.ORCID-id: 0000-0002-3965-7371
Högskolan i Skövde, Forskningscentrum för Systembiologi. Högskolan i Skövde, Institutionen för vård och natur.
Linköping University.
Vise andre og tillknytning
2010 (engelsk)Inngår i: Advances in Complex Systems, ISSN 0219-5259, Vol. 13, nr 2, s. 239-250Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Theoretical exploration of network structure significance requires a range of different networks for comparison. Here, we present a new method to construct networks in a spatial setting that uses spectral methods in combination with a probability distribu-tion function. Nearly all previous algorithms for network construction have assumed randomized distribution of links or a distribution dependent on the degree of the nodes.We relax those assumptions. Our algorithm is capable of creating spectral networks along a gradient from random to highly clustered or diverse networks. Number of nodes and link density are specified from start and the structure is tuned by three parameters (γ, σ, κ). The structure is measured by fragmentation, degree assortativity, clusteringand group betweenness of the networks. The parameter γ regulates the aggregation in the spatial node pattern and σ and κ regulates the probability of link forming.

sted, utgiver, år, opplag, sider
World Scientific Publishing Company , 2010. Vol. 13, nr 2, s. 239-250
HSV kategori
Forskningsprogram
Naturvetenskap
Identifikatorer
URN: urn:nbn:se:his:diva-4500DOI: 10.1142/S0219525910002517ISI: 000279727100006Scopus ID: 2-s2.0-77952269152OAI: oai:DiVA.org:his-4500DiVA, id: diva2:381607
Tilgjengelig fra: 2010-12-28 Laget: 2010-12-28 Sist oppdatert: 2017-11-27bibliografisk kontrollert
Inngår i avhandling
1. Network analysis and optimization of animal transports
Åpne denne publikasjonen i ny fane eller vindu >>Network analysis and optimization of animal transports
2012 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

This thesis is about animal transports and their effect on animal welfare. Transports are needed in today’s system of livestock farming. Long transports are stressful for animals and infectious diseases can spread via animal transports. With optimization methods transport times can be minimized, but there is a trade-off between short distances for the animals and short distances for the trucks. The risk of disease spread in the transport system and disease occurrence at farms can be studied with models and network analysis.

The animal transport data and the quality of the data in the Swedish national database of cattle and pig transports are investigated in the thesis. The data is analyzed regarding number of transports, number of farms, seasonality, geographical properties, transport distances, network measures of individual farms and network measures of the system. The data can be used as input parameters in epidemic models.

Cattle purchase reports are double reported and we found that there are incorrect and missing reports in the database. The quality is improving over the years i.e. 5% of cattle purchase reports were not correctly double reported in 2006, 3% in 2007 and 1% in 2008. In the reports of births and deaths of cattle we detected date preferences; more cattle births and deaths are reported on the 1st, 10th and 20th each month. This is because when we humans don’t remember the exact number we tend to pick nice numbers (like 1, 10 and 20). This implies that the correct date is not always reported.

Network analysis and network measures are suggested as tools to estimate risk for disease spread in transport systems and risk of disease introduction to individual holdings. Network generation algorithms can be used together with epidemic models to test the ability of network measures to predict disease risks. I have developed, and improved, a network generation algorithm that generates a large variety of structures.

In my thesis I also suggest a method, the good choice heuristic, for generating non-optimal routes. Today coordination of animal transports is neither optimal nor random. In epidemic simulations we need to model routes as close to the actual driven routes as possible and the good choice heuristic can model that. The heuristic is tuned by two parameters and creates coordination of routes from completely random to almost as good as the Clarke and Wright heuristic. I also used the method to make the rough estimate that transport distances for cattle can be reduced by 2-24% with route-coordination optimization of transports-to-slaughter.

Different optimization methods can be used to minimize the transport times for animal-transports in Sweden. For transports-to-slaughter the strategic planning of “which animals to send where” is the first step to optimize. I investigated data from 2008 and found that with strategic planning, given the slaughterhouse capacity, transport distances can be decreased by about 25% for pigs and 40% for cattle. The slaughterhouse capacity and placement are limiting the possibility to minimize transport times for the animals. The transport distances could be decreased by 60% if all animals were sent to the closest slaughterhouse 2008. Small-scale and mobile slaughterhouses have small effect on total transport work (total transport distance for all the animals) but are important for the transport distances of the animals that travel the longest.

 

 

sted, utgiver, år, opplag, sider
Linköping University, 2012. s. 46
Serie
Linköping Studies in Science and Technology, Dissertation, ISSN 0345-7524 ; 1434
HSV kategori
Forskningsprogram
Naturvetenskap
Identifikatorer
urn:nbn:se:his:diva-6492 (URN)978-91-7519-939-9 (ISBN)
Merknad

I Håkansson, N., Henningsson, M., Rönnqvist, M. & Wennergren U., June 2007 Route planning reduces the costs of animal transportation: Animal welfare versus economics. pp. 1044–048. Tartu, Estonia: XIII Int. Congr. Animal hygiene.

II Nöremark, M., Håkansson, N., Lindström, T., Wennergren, U. & Sternberg Lewerin, S., 2009 Spatial and temporal investigations of reported movements, births and deaths of cattle and pigs in Sweden. Acta Veterinaria Scandinavica 51(37).

III Nöremark, M., Håkansson, N., Sternberg Lewerin, S., Lindberg, A. & Jonsson, A., 2011 Network analysis of cattle and pig movements in Sweden: Measures relevant for disease control and risk based surveillance. Preventive Veterinary Medicine 99, pp 78 –90.

IV Håkansson, N., Jonsson, A., Lennartsson, J., Lindström, T. &Wennergren, U., 2010 Generating structure specific networks. Advances in Complex Systems (ACS) 13(02), pp 239–50.

V Lennartsson, J., Håkansson, N.,Wennergren, U. & Jonsson, A., 2012 SpecNet: a spatial network algorithm that generates a wide range of specific structures.(submitted manuscript 1).

VI Håkansson, N., Flisberg, P., Algers, B., Rönnqvist, M. & Wennergren, U., 2012 A strategic analysis of slaughterhouses and animal transportation in Sweden. (manuscript).

Tilgjengelig fra: 2012-10-10 Laget: 2012-10-09 Sist oppdatert: 2017-11-27bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekstScopus

Personposter BETA

Håkansson, NinaJonsson, AnnieLennartsson, Jenny

Søk i DiVA

Av forfatter/redaktør
Håkansson, NinaJonsson, AnnieLennartsson, Jenny
Av organisasjonen
I samme tidsskrift
Advances in Complex Systems

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 1041 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf