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Visar resultat 1 - 5 av 109 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Integrated Access and Backhaul for 5G and Beyond (6G)

   Författare :Charitha Madapatha Madapathage Don; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Stochastic geometry; Node selection; Beyond 5G; Backhaul; 6G; Blockage; Coverage probability; Poisson point process PPP ; Integrated access and backhaul IAB ; Relay; Constrained deployment; 5G new radio NR ; Tree foliage; Millimeter wave mmWave communications; Densification; 3GPP; Wireless backhaul; Routing; Genetic algorithm GA ; Topology optimization;

   Sammanfattning : Enabling network densification to support coverage-limited millimeter wave (mmWave) frequencies is one of the main requirements for 5G and beyond. It is challenging to connect a high number of base stations (BSs) to the core network via a transport network. LÄS MER

3. 2. Towards Context Information-based High-Performing Connectivity in Internet of Vehicle Communications

   Författare :Hao Guo; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; temporal correlation; relay; Internet-of-vehicles IoV ; reconfigurable intelligent surface; throughput; wireless backhaul; outage probability; channel state information CSI ; 5G B5G; spatial correlation; rate adaptation; mobile relay; 6G; vehicle-to-everything V2X ; Marcum Q-function; integrated access and backhaul IAB ; predictor antenna; blockage; millimeter wave;

   Sammanfattning : Internet-of-vehicles (IoV) is one of the most important use cases in the fifth generation (5G) of wireless networks and beyond. Here, IoV communications refer to two types of scenarios: serving the in-vehicle users with moving relays (MRs); and supporting vehicle-to-everything (V2X) communications for, e.g., connected vehicle functionalities. LÄS MER

4. 3. Numerical Study of Laminar, Transitional and Turbulent Flow Past Rectangular Cylinders

   Författare :Ahmad Sohankar Esfahani; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; blockage; outlet boundary condition; rectangular cylinders; onset of vortex shedding; angle of incidence; incompressible flow; LES; DNS; transition; finite volumes; Reynolds number; numerical simulation; square cylinder;

   Sammanfattning : The subject of flow past slender bluff bodies is of relevance to technical problems associated with energy conservation, structural design and acoustic emissions. The present work is restricted to an important sub-class of slender bluff body flow --- the incompressible flow around a stationary cylinder having a rectangular cross section, the cylinder being exposed to a constant free stream velocity. LÄS MER

5. 4. Aerodynamic Design and Installation Effects of Automotive Electric Cooling Fans

   Författare :Debarshee Ghosh; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Blade Element Momentum BEM ; low-pressure axial fans; electric cooling fans; automotive thermal management; CFD simulations; upstream blockage; fans in parallel;

   Sammanfattning : Electric cooling fans play a crucial role in automotive thermal management. They generate the airflow required for heat rejection from the expended coolant circulating within the heat exchanger. This thesis focuses on the aerodynamic design and installation effects of electric cooling fans or "E-fans". LÄS MER

7. 5. Snow contamination of cars: Collisions of ice particles with surfaces

   Författare :Tobias Eidevåg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ice adhesion; Snow adhesion; coefficient of restitution; particle impacts; premelting; radar blockage;

   Sammanfattning : Seasonal snow cover on roads causes car accidents that lead to human suffering and economic loss. Snow cover decreases visibility and road-tire friction. Advanced active safety systems have been developed to cope with sudden changes in driving conditions and have been engineered to act as quickly as possible. LÄS MER