Adaptive independent Metropolis--Hastings

We propose an adaptive independent Metropolis--Hastings algorithm with the ability to learn from all previous proposals in the chain except the current location. It is an extension of the independent Metropolis--Hastings algorithm. Convergence is proved provided a strong Doeblin condition is satisfied, which essentially requires that all the proposal functions have uniformly heavier tails than the stationary distribution. The proof also holds if proposals depending on the current state are used intermittently, provided the information from these iterations is not used for adaption. The algorithm gives samples from the exact distribution within a finite number of iterations with probability arbitrarily close to 1. The algorithm is particularly useful when a large number of samples from the same distribution is necessary, like in Bayesian estimation, and in CPU intensive applications like, for example, in inverse problems and optimization.Comment: Published in at http://dx.doi.org/10.1214/08-AAP545 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org

Organisering og samarbeid i byggeprosjekter

Denne oppgaven har tatt for seg problemstillingen hvordan Forsvarsbygg ivaretar brukerens behov. Forsvaret i Østerdal garnison har siden 2007 jobbet med å identifisere og fremme det fremtidige behovet for forlegning til vervede soldater og befal. I denne sammenhengen har det vært gjennomført fem byggetrinn for å møte dette behovet. Forsvarsbygg, som Forsvarets eiendomsaktør, har ledet arbeidet med prosjektering og bygging av disse og må derfor forholde seg til Forsvarets (brukeren) behov for bygningsmasse. Oppgaven fokuserer på hvordan Forsvarsbygg organiserer sine byggeprosjekter, og hvordan brukerens behov kommer til syne i disse. Dette er gjort gjennom å undersøke de generelle retningslinjer for fremming av behov, samt å visualisere disse i en case. Datainnhenting er gjennomført ved kvalitativ metode – intervju av respondenter i de to undesøkelsesenhetene Forsvaret og Forsvarsbygg

Resilient internetwork routing over heterogeneous mobile military networks

Mobile networks in the military tactical domain, include a range of radio networks with very diverse characteristics and which may be employed differently from operation to operation. When interconnecting networks with dissimilar characteristics (e.g. capacity, range, mobility) a difficult trade-off is to fully utilize the diverse network characteristics while minimizing the cost. To support the ever increasing requirements for future operations it is necessary to provide tools to quickly alter the rule-set during an ongoing operation, due to a change in operation and/or to support different needs. Our contribution is a routing protocol which targets these challenges. We propose an architecture to connect networks with different characteristics. One key point is that low capacity links/networks segments can be included in the heterogeneous network, these segments are protected from overload by controlling where and when signaling/data traffic is sent. The protocol supports traffic policing, including resource reservation. The other key point is the ability to quickly alter the network policy (rules-set) including QoS support during an operation or from operation to operation.author postprin

Selected Issues of QoS Provision in Heterogenous Military Networks

Tactical ad-hoc networks are evolving today towards complex heterogeneous networks in terms of architecture, protocols and security. Due to the difference in network resources and reliability, end-to-end quality of service provisioning becomes very challenging. If we also take into account communication issues such as unpredictable connectivity, preferential forwarding for special traffic classes, intermittency due to node or communication link failure, the problem is further aggravated.In this article, we examine the major challenges that must be solved in order to provide efficient QoS provisioning in the heterogeneous network. Finally we describe QoS-aware mechanisms for inter-domain and intra-domain heterogeneous networks, also including real-time services provision in highly mobile environments.

Sickness absence around contact with outpatient mental health care services – differences between migrants and non-migrants:a Norwegian register study

Background: Mental disorders are a leading cause of sickness absence. Some groups of migrants are at higher risk of both mental disorder and sickness absence. Yet, research on sickness absence in relation to mental disorders among migrants is limited. This study investigates differences in sickness absence in the twelve-month period around contact with outpatient mental health services between non-migrants and various migrant groups with different length of stays. It also considers whether these differences are similar for men and women.Methods: Using linked Norwegian register data, we followed 146,785 individuals, aged 18–66 years, who had attended outpatient mental health services and who had, or had recently had, a stable workforce attachment. The number of days of sickness absence was calculated for the 12-month period surrounding contact with outpatient mental health services. We applied logistic regression and zero-truncated negative binomial regression to assess differences in any sickness absence and number of days of absence between non-migrants and migrants, including refugees and non-refugees. We included interaction terms between migrant category and sex.Results: Refugee men and other migrant men from countries outside the European Economic Area (EEA) had a higher probability of any sickness absence in the period surrounding contact with outpatient mental health services than their non-migrant counterparts. Women from EEA countries with stays of less than 15 years had a lower probability than non-migrant women. Additionally, refugees, both men and women, with 6–14 years in Norway had more days of absence while EEA migrants had fewer days than their non-migrant counterparts.Conclusions: Refugee men and other non-EEA migrant men appear to have higher sickness absence than non-migrant men around the time of contact with services. This finding does not apply to women. Several probable reasons for this are discussed, though further research is required to understand why. Targeted strategies to reduce sickness absence and support the return to work for refugees and other non-EEA migrant men are needed. Barriers to timely help-seeking should also be addressed.</p

Mental disorder and subsequent marital separation among migrant and non-migrant women

Using national register data between 2006-2014, we investigated the relationship between outpatient mental health service use (a proxy for mental disorder) and subsequent marital separation among women in Norway and whether the strength of the association differed for migrant and non-migrant women. Our sample population included 679,928 married women aged 18-60 years. Service use was strongly associated with marital separation among all women. The relationship was stronger for Filipinas but weaker for Somalis and Russians, compared with non-migrant women. Migration-related factors may influence marital separation among migrant women and barriers to care are likely to exist.</p

Same but different: meaning-making among refugee and non-refugee youths

Purpose: There is substantial research on the experiences, needs and well-being of unaccompanied refugee adolescents, but less is known about existential aspects of their lives. The purpose of the current study is to explore existential meaning-making among unaccompanied refugee children. Design/methodology/approach: The informants in this study are young unaccompanied refugees (n = 30) living in Norway, and young Norwegians (n = 46). The authors undertook a secondary analysis of in-depth qualitative refugee interview data and a quantitative analysis of questionnaire data from Norwegian informants. Findings: Both the refugee youths and the Norwegian youths expressed that social relationships and connections to others were most important for meaning. Moreover, both groups emphasized the importance of relatedness and generativity, i. e. commitment to worldly affairs beyond one’s immediate needs. The main differences between the two groups were related to the significance attached to religion and to loneliness. Research limitations/implications: The comparison between the two groups is only possible to some degree. Secondary analyses have some limitations, as well as strengths. Practical implications: The findings may be useful for supporting young refugees, as they provide insights into less-studied aspects of their lives. Originality/value: The originality of this study lies in the focus on and broad interpretation of meaning, of secondary data analyses, and of comparisons between youths that are refugees versus non-refugees.publishedVersio

Measurements of CH4 and CO2 relative permeability in hydrate-bearing sandstone

This paper reports measurements of relative permeability to methane (CH4) and carbon dioxide (CO2) in hydrate-bearing sandstone core samples. The CH4 (or CO2) permeability was measured at reservoir conditions for different hydrate and brine saturations. The saturation span ranged from 0.18 to 0.60 (frac.) for CH4 gas and from 0.37 to 0.70 (frac.) for liquid CO2. The hydrate saturation ranged from 0.18 to 0.61 (frac.). The growth of hydrates within sandstone pores reduced the permeability for both the CH4 and CO2 system significantly, and the relative reduction was more pronounced for lower gas saturations. This effect is currently not included in numerical models of relative permeability in hydrate-bearing sediments and should be considered. The reported measurements are relevant to production-forecasting of methane gas from hydrate reservoirs and CO2 storage schemes where CO2 hydrates may provide self-sealing in cold aquifers.publishedVersio

Preparation for Denitrification and Phenotypic Diversification at the Cusp of Anoxia: a Purpose for N2O Reductase Vis-à-Vis Multiple Roles of O2

acceptedVersio