| 1. |
- Almers, Peter, et al.
(författare)
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Survey of channel and radio propagation models for wireless MIMO systems
- 2007
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Ingår i: Eurasip Journal on Wireless Communications and Networking. - : Springer Science and Business Media LLC. - 1687-1472 .- 1687-1499. ; 2007
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Tidskriftsartikel (refereegranskat)abstract
- This paper provides an overview of the state-of- the-art radio propagation and channel models for wireless multiple-input multiple-output (MIMO) systems. We distinguish between physical models and analytical models and discuss popular examples from both model types. Physical models focus on the double-directional propagation mechanisms between the location of transmitter and receiver without taking the antenna configuration into account. Analytical models capture physical wave propagation and antenna configuration simultaneously by describing the impulse response (equivalently, the transfer function) between the antenna arrays at both link ends. We also review some MIMO models that are included in current standardization activities for the purpose of reproducible and comparable MIMO system evaluations. Finally, we describe a couple of key features of channels and radio propagation which are not sufficiently included in current MIMO models. Copyright c 2007 P. Almers et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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| 2. |
- Bergsjö, D., et al.
(författare)
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Product lifecycle management for cross-x engineering design
- 2007
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Ingår i: Proceedings of ICED 2007, the 16th International Conference on Engineering Design. - 1904670024 - 9781904670025
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Konferensbidrag (refereegranskat)abstract
- This paper deal with the urgent problem to create integrated PLM solutions in today's European automotive industry. Two European automotive companies have been used as case companies in order to carry out these studies. Configuration management and engineering change management are two information management processes that span throughout the extended company, through engineering domains and through the product lifecycle. This makes them ideal as study objects to create new methods, and to enable PLM for cross-x engineering design. Several guidelines regarding IT system architectures for cross-x PLM are presented, e.g.: modularity, central coordination, standard communication, minimum process redundancy, and general modelling constructs.
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| 3. |
- Faulwetter, Jennifer L, et al.
(författare)
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Microbial processes influencing performance of treatment wetlands : A review
- 2009
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Ingår i: ECOLOGICAL ENGINEERING. - : Elsevier BV. - 0925-8574. ; 35:6, s. 987-1004
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Tidskriftsartikel (refereegranskat)abstract
- This review summarizes the microbial mechanisms responsible for removal of carbon, nitrogen. and sulfur compounds in treatment wetlands (TWs) and identifies, categorizes and compares various techniques, from plate count to more modern genomic methods used to elucidate these mechanisms. Removal of a particular pollutant is typically associated with a specific microbial functional group, therefore employment of design and operational methodologies that enhance the activity of that group will better optimize performance. Redox condition is a manipulable parameter that can be used to optimize growth of a targeted functional group, therefore factors influencing the TW redox condition and its influence on organic carbon removal mechanisms are emphasized. Environmental factors influencing growth and activity of N and S cycling microbes (including temperature, pH, salinity, plant species selection and availability of organic carbon and/or inhibiting substances) are discussed with particular attention to factors that might be manipulated. This information is used to offer design and operational methodologies that might enhance growth of a desirable microbial functional group and project what additional microbially-focused research is required to better optimize TW performance.
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