Search results for "VDP::Matematikk og Naturvitenskap: 400"
showing 10 items of 647 documents
Impact of a Social Constructivist Instructional Strategy on Performance in Algebra with a Focus on Secondary School Students
2020
There have been perennial concerns on the low academic performance of students among researchers and other education stakeholders. Innovative teaching strategies have, therefore, gained prominence in the field of mathematics education. The purpose of this study is to investigate the impact of a social constructivist instructional strategy on students’ performance in algebra. The present study is quasi-experimental, and its type is a posttest control group involving 154 secondary school students that are randomly selected across four intact classes. The random selection of students to treatment and control controls is assumed to improve the validity of the results. Two research questions are…
Fall Detection Based on the Instantaneous Doppler Frequency : A Machine Learning Approach
2019
Modern societies are facing an ageing problem which comes with increased cost of healthcare. A major share of this ever-increasing cost is due to fall related injuries, which urges the development of fall detection systems. In this context, this paper paves the way for building of a radio-frequency-based fall detection system. This paper presents an activity simulator that generates the complex channel gain of indoor channels in the presence of one person performing three different activities, namely, slow fall, fast fall, and walking. We built a machine learning framework for activity recognition based on the complex channel gain. We assess the recognition accuracy of three different class…
Atlantic salmon survival at sea: temporal changes that lack regional synchrony
2022
Spatial and temporal synchrony in abundance or survival trends can be indicative of whether populations are affected by common environmental drivers. In Atlantic salmon (Salmo salar L.), return rates to natal rivers have generally been assumed to be affected primarily by shared oceanic conditions, leading to spatially synchronous trends in mortality. Here, we investigated the existence of parallel trends in salmon sea survival, using data on migrating smolts and returning adults from seven Canadian populations presumed to share feeding grounds. We analysed sea survival, using a Bayesian change-point model capable of detecting non-stationarity in time series data. Our results indicate that w…
An Urban Governance Framework for Including Environmental Migrants in Sustainable Cities
2022
This article proposes an urban governance framework for including environmental migrants in sustainable cities. It outlines the links among environmental migration, vulnerability, and sustainability, showing how vulnerability and sustainability are not about the environment or the human condition as snapshots in space and time, but rather are long-term, multi-scalar, ever-evolving processes. This theoretical baseline is followed by a description of some practical approaches already applied for including environmental migrants in sustainable cities. The wide variety and lack of cohesion justifies the need for a framework, leading to three principal characteristics of a governance framework s…
Exploration of stationary time-series’ network properties : Visibility-and Horizontal visibility graph of Gaussian white noise, AR (1), MA (1) and AR…
2019
Master's thesis Business Administration BE501 - University of Agder 2019 We haverecordedthe network properties ofstochastic processes’whitenoise,푀퐴(1), 퐴푅(1)and 퐴푅푀퐴(1,1)bymeansof visibility-and horizontal visibility algorithms. The sample series of the stochastic processeswere artificially generated and used in simulationswith multiple repetitions. We examined six global network properties:mean degree, normalized degree centrality, degree distribution, transitivity, assortativity and average geodesic pathtodiscover how theyreflect the structure of the series. These properties were also used to disclose change in behavior due to variation in the series length.Our contribution to the literat…
Feeding Ecology of Harbour Seals (Phoca vitulina) in Southern Norway
2017
Master's thesis Aquatic Ecology BIO500 - University of Agder 2017 In order to understand ecosystem dynamics and functions it is vital to have knowledge about relationships between predator and prey. Harbour seals (Phoca vitulina) are piscivorous marine mammals found at or near the top of marine food webs. Being mainly piscivores, harbour seals have the potential to come into conflict with fishermen and fisheries. Recently, as the Skagerrak and Kattegat population of harbour seals has increased, claims that seals are depleting the cod population have surfaced. Using scat sampling and otolith identification, harbour seal diet was estimated in four separate locations along the coast of souther…
Assessing the impacts of marine protected areas on wrasse populations in Norway
2020
Master's thesis in Coastal ecology (BIO501)
Homing Ability of Goldsinny Wrasse (Ctenolabrus rupestris)
2021
Master's thesis in Coastal ecology (BIO501) After the discovery of delousing abilities of temperate wrasses, several wrasse species are increasingly harvested in Norway and supplied to salmonid aquafarms to combat sea lice infestations. An increased harvesting intensity has raised concerns regarding the sustainability of this comparatively new fishery. Therefore, more research is needed about the targeted wrasses species. Goldsinny wrasses (Ctenolabrus rupestris)are known for having small home ranges and being highly territorial. Minimum size restrictions oblige fishermen to release goldsinnies smaller than 11 cm back to the sea, but this is often done far from the capture site. It is very …
Visual fish assemblage inventory of outer Oslo fjord, with special emphasis on young-of-the-year Atlantic cod (Gadus morhua)
2021
Master's thesis in Coastal ecology (BIO501) The coastal zone along the outer Oslofjord is physically unique and home to many ecologically depleted and economically important species, including Atlantic cod (Gadus morhua). Coastal cod in Skagerrak is divided into two ecotypes that co-exist in outer Oslofjord. Remnant local populations are considered sensitive to climate disturbances and anthropogenic influences. Recruitment of cod in Skagerrak is monitored in the annual beach seine sampling. A strong year-class of cod recruited to nursery areas in outer Oslo fjord in 2017. Although recruitment of cod has been monitored extensively in Skagerrak, studies have only recently begun to examine the…
Long term effects of activated carbon on benthic communities
2021
Master's thesis in Coastal ecology (BIO501) Thin-layer capping with activated carbon (AC) has a potential as situ remediation method for sediments exposed to hydrophobic organic compounds (HOCs). This treatment was applied at two test fields; one in the Eidangerfjord (95 m) and the other in the Ormerfjord (30 m) in 2009. These two fjords are a part of the Grenland fjord system which have a long history of contaminated sediments. In this study we will address long-term effects of thin-layer capping with AC on the benthic community nine years later. Number of individuals, species and biomass was significantly reduced in both test fields compared to their corresponding reference fields. The di…