Search results for "52"
showing 10 items of 1043 documents
Channel simulation models for mobile broadband communication systems
2009
Doktorgradsavhandling i informasjons- og kommunikasjonsteknologi, Universitetet i Agder, Grimstad, 2009 Mobile broadband wireless communication systems (MBWCS) are emerging as a solution to provide broadband services to users on the move. These systems are expected to operate in a wide variety of propagation scenarios, at different mobile speeds, and at various frequency bands. Under such a variety of requirements, flexible and efficient channel simulation models will prove fundamental for the laboratory analysis of MBWCS. Currently, most of the existing channel simulation models are either too complex as to allow for an efficient performance investigation of MBWCS, or they cannot be applie…
Using Digital Hydraulics in Secondary Control of Motor Drive
2020
Due to the increased focus on pollution and global warming, there is a demand for energy efficient systems. This also applies to the offshore oil and gas industry. Normally used hydraulic systems tend to suffer from low energy efficiency, especially when operating with part loads. In the last decades, a new pump and motor technology has experienced increased interest due to the potential of high energy efficiency in a wide range of operation conditions. This new technology is called digital displacement machine technology. Nowadays, there is a desire from the offshore oil and gas industry to use this digital displacement machine technology to design highly efficient hydraulic winch drive sy…
Stability analysis with H∞ performance of production networks with autonomous work systems and time-varying delays
2011
Author's version of a chapter in the book: Proceeding of the 30th Chinese Control Conference. Also available from the publisher at: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6001452&tag=1 This paper considers the problem of stability analysis with an H ∞ performance for a class of production networks of autonomous work systems with delays in the capacity changes. The system under consideration shares information between work systems and the work systems adjust capacity with the objective of maintaining a desired amount of local work in progress. An appropriate Lyapunov function is utilized to establish some delay-range-dependent conditions in terms of linear matrix inequalitie…
Advances in Permanent Deformation Modeling of Asphalt Concrete-A Review.
2022
Permanent deformation is one of the dominant asphalt concrete damages. Significant progress has been made to realistically predict the damage. In the last decade, the mechanistic approach has been the focus of research, and the fundamental theories of viscoelasticity, viscoplasticity, continuum mechanics, and micromechanics are applied to develop the material laws (constitutive equations). This paper reviews the advancement of permanent deformation models including analogical, microstructural, and continuum-based methods. Pavement analysis using the nonlinear damage approach (PANDA) is the most comprehensive and theoretically sound approach that is available in the literature. The model cou…
Livssyklusanalyse (LCA) av vegger i bindingsverk med kontinuerlig isolasjon : En sammenlignende LCA-studie av ytterveggsystemer i tre for miljøoptima…
2020
Master's thesis in Civil and structural engineering (BYG508) The building industry istaking measures in order to reduce its large carbon footprint. However, even more ecofriendly building solutions need to be used. External walls are constructed with a great usage of materials -in addition to being the building component were large portions of heat escape.This study answers the research question “How does timber-framed external walls with continuous outer insulation(BKI)perform from an environmental point of view?”. The software SimaPro is used to compare different types of external walls with regards to CO2-emissions. The findings in the study show thatBKI wallsdo have good energy efficien…
Relevance- and Aggregation-based Scheduling for Data Transmission in IEEE 802.15.4e IoT Networks
2017
Master's thesis Information- and communication technology IKT590 - University of Agder 2017 Internet of thing (IoT) is regarded as a new communicating paradigm with Internet connectivity enabling embedded devices to interact with each other on a global scale. IoT has the potential to become the largest producer of information because of a massive number of connected devices with diverse applications ranging from environmental monitoring, home, and building automation. This ubiquitous connectivity requires reliability, efficiency, and sustainability of access to information. As an enabling technology, wireless sensor networks (WSNs) have opened new opportunity with recent technological devel…
Nytt resirkulert tilslag produsert fra grave- og byggavfall
2020
Master's thesis in Civil and structural engineering (BYG508) Recycled aggregate produced from excavation and construction waste is an important resource. This is because increased use of recycled aggregate will contribute to reduce the amount of waste delivered to landfill, which is an important environmental benefit. Recycled aggregate will replace some of the application areas of natural crushed aggregate, this will reduce the extraction of primary raw materials. The focus of this master thesis is to investigate and document variations in mechanical properties of recycled aggregate produced from excavation mass. The purpose of this is to document the stability of mechanical properties and…
UHPC i norsk brobygging
2020
Master's thesis in Civil and structural engineering (BYG508)
Skjærkapasitet av ultrahøyfast fiberarmert betong – verifikasjon av designstandard
2018
Masteroppgave bygg BYG508 - Universitetet i Agder 2018 Ultra High Performance Fiber Reinforced Concrete (UHPFRC) is a concrete that is still not in use in Norway. This is, as the name implies, a strong concrete, with high ductility from the fibres. To be able to use this concrete in Norway in the future, it is necessary to develop a national standard for UHPFRC. The concrete is in use in some countries, some of these are France, USA, Japan and Canada. The French standard NF P18-710 is based on Eurocode 2, but it is customized for UHPFRC. The method to calculate the shear capacity is different, both because of the concrete and because of the use of fibres. To calculate how much the fibres wi…
Silica Green Stone as an SCM in concrete paving stones production : In order to reduce the total environmental footprint
2021
Master's thesis in Civil and structural engineering (BYG508) The cement industry is responsible for around 7% of the global CO2 emissions. Reducing this number has been on the forefront of the industry's mind for decades, but even with constant improvement and constant reduction in CO2 emissions per tonne cement used, the increasing globalization has kept the emissions high. Research in the industry has discovered supplementary cementitious materials (SCMs), that when partly replacing cement will produce most of the same results. SCMs are by-products from other industries and natural progression has led to the need for new ones. This thesis is, together with UiA, Aaltvedt Betong, SINTEF and…