| 1. |
- Aydogdu, Canan, 1978, et al.
(författare)
-
Radar Interference Mitigation for Automated Driving : Exploring Proactive Strategies
- 2020
-
Ingår i: IEEE signal processing magazine (Print). - Piscataway : Institute of Electrical and Electronics Engineers (IEEE). - 1053-5888 .- 1558-0792. ; 37:4, s. 72-84
-
Tidskriftsartikel (refereegranskat)abstract
- Autonomous driving relies on a variety of sensors, especially radars, which have unique robustness under heavy rain/fog/snow and poor light conditions. With the rapid increase of the amount of radars used on modern vehicles, where most radars operate in the same frequency band, the risk of radar interference becomes a compelling issue. This article analyzes automotive radar interference and proposes several new approaches that combine industrial and academic expertise toward the goal of achieving interference-free autonomous driving (AD). © IEEE.
|
|
| 2. |
- Aydogdu, Canan, 1978, et al.
(författare)
-
Radar Interference Mitigation through Active Coordination
- 2021
-
Ingår i: IEEE National Radar Conference - Proceedings. - : IEEE. - 1097-5659. ; 2021-May, s. 1-6
-
Konferensbidrag (refereegranskat)abstract
- Intelligent transportation is heavily reliant on radar, which have unique robustness under heavy rain/fog/snow and poor light conditions. With the rapid increase of the number of radars used on modern vehicles, most operating in the same frequency band, the risk of radar interference becomes an important issue. As in radio communication, interference can be mitigated through coordination. We present and evaluate two approaches for radar interference coordination, one for FMCW and one for OFDM, and highlight their challenges and opportunities.
|
|
| 3. |
- Carvajal, Gisela, 1983, et al.
(författare)
-
Comparison of Automotive FMCW and OFDM Radar Under Interference
- 2020
-
Ingår i: IEEE National Radar Conference - Proceedings. - New York, NY : IEEE. - 1097-5659. ; 2020-September
-
Konferensbidrag (refereegranskat)abstract
- Automotive radars are subject to interference in spectrally congested environments. To mitigate this interference, various waveforms have been proposed. We compare two waveforms (FMCW and OFDM) in terms of their radar performance and robustness to interference, under similar parameter settings. Our results indicate that under proper windowing both waveforms can achieve similar performance, but OFDM is more sensitive to interference.
|
|
| 4. |
- Ghasemi, Yahya, 1982-
(författare)
-
Aggregates in Concrete Mix Design
- 2017
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The importance of studying the behaviour and properties of concrete can be highlighted by considering the fact that concrete is the most used man-made material in the world. The very first step in making concrete is its mix design and deciding the type and amount of constitutes used in the production of concrete which should fulfil the requirements of the final product. Mix design models are commonly used for the purpose of proportioning concrete ingredients while anticipating the properties of the final product. The current document deals with the commonly used principals in mix design models namely particle packing theory and excess water/paste layer theories. The conducted studies includes an investigation on accuracy of particle packing models (Toufar, 4C, CPM) and also tries to address the issue with measurement of specific surface area of particles as an essential input to water/paste layer theories. It has been observed that the particle packing models can predict the packing density with acceptable margin. However, it should be mentioned that the particle packing models by themselves are not mix design models but should be rather used as a part of a mix design. In addition, it was found that the accuracy of calculating the specific surface area of particles based on their size distribution curve can be further improved by assuming angular platonic solids as uniform shape of aggregate instead of traditional approach of assuming spheres for aggregates’ shape.
|
|
| 5. |
- Ghasemi, Yahya, 1982-
(författare)
-
Flowability and proportioning of cementitious mixtures
- 2019
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Understanding the role of constituents of cementitious mixtures as the most globally used human-made material and their effect on the flowability of the blends is of great importance. A comprehensive understanding of the ingredients of mixtures allows for optimized proportioning of constituents and can lead to a reduction in cement and water demand of the blends.The thesis focuses on relating the flow of mixtures to the specific surface area of the particles through the concepts of excess water layer theory by assuming that the particles are enveloped by a thin film layer that separates the grains and lubricates their surfaces. However, in order to study the film thickness, it is inevitable to consider packing density and specific surface area of the particles. Both of the mentioned parameters and their influence on water requirement of mixtures were investigated as a part of the project.The theoretical part of the thesis includes background and explanation of the concepts and theories used in conducting the research including particle packing theory, specific surface area, and excess layer theories. In addition, the thesis attempts at defining and formulating terms and parameters such as representative shape, mixer efficiency, and optimal packing.The experimental part of the thesis consists of laboratory measurements of packing density in the loose state, estimation of specific surface area using microtomography and slump tests for mortar and concrete.The results of the thesis indicate that the available packing models can estimate the packing density with acceptable accuracy. In addition, it was shown that it is possible to estimate flowability of mixtures based on information about the specific surface area of the constituents. A mix design approach is introduced which predicts flow spread of slump test, a measure that is often used in laboratories and at the building sites.Moreover, the research revealed that the estimation of the specific surface area of particles can be improved by assuming a platonic solid shape for the particles instead of spheres. Furthermore, the mixer efficiency was quantified and optimization of mixtures against packing density and water requirement was explained.The finding of the project lays a foundation for a simple workability based mix design approach.
|
|
| 6. |
- Nilsson, Tania, et al.
(författare)
-
Injury incidence in male elite youth football players is associated with preceding levels and changes in training load
- 2023
-
Ingår i: BMJ Open Sport and Exercise Medicine. - London : BMJ Publishing Group Ltd. - 2055-7647. ; 9:4, s. 1-7
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives Elite youth football players miss out on a large part of seasonal training due to injury. Limited research suggests an association between external and internal training load (TL) and injury incidence in elite youth football. This study analysed external and internal TL variables and their association with injury incidence in a group of male elite youth football players over four seasons. Methods Measures of external and internal TL and injury incidence of 56 male elite youth football players (age 17-19 years) were collected throughout four seasons. Heart rate, session rating of perceived exertion andGlobal Positioning System (GPS) variables were analysed. Individual players' TL during the 30 days leading up to injury was compared with 30-day injury-free control periods. Change in TL through the periods was also analysed. Results Eighty-five injuries were included for analysis, showing that for most TL variables, the average levels were significantly lower during the period leading up to injury. Significant increases for the majority of TL variables were also found during the periods leading up to injury, while the control periods did not show any significant change. Conclusion A lower and/or increasing average TL volume over 30 days might increase the risk of injury in male elite youth football players. Avoiding long-term drops in TL and balance increases in TL might be beneficial to reduce injury risk. © Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
|
|
| 7. |
|
|
