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Visar resultat 1 - 5 av 40 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Analysis and Design of Conformal Array Antennas

   Författare :Patrik Persson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Conformal antennas; conformal arrays; UTD; high frequency method; MoM; hybrid method; mutual coupling; singly curved surface; doubly curved surface; geodesics; dielectric covered circular cylinder; non-paraxial region. paraxial region; waveguide fed; Electrical engineering; Elektroteknik;

   Sammanfattning : Today there is a great need for communication between people and even between things, using systems onboard e.g. aircraft, cars, ships and satellites. As a consequence, these communications needs require antennas mounted on or integrated in the surfaces of different vehicles or platforms, i. LÄS MER

3. 2. Theoretical prediction of properties of atomistic systems : Density functional theory and machine learning

   Författare :Alexander Lindmaa; Rickard Armiento; Igor Abrikosov; Torbjörn Björkman; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : The prediction of ground state properties of atomistic systems is of vital importance in technological advances as well as in the physical sciences. Fundamentally, these predictions are based on a quantum-mechanical description of many-electron systems. LÄS MER

4. 3. Voltage Stabilizers: From Design to Synthesis, Processing and Electrical Characterization

   Författare :Markus Jarvid; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Polyethylene; Degradation; XLPE; Electrical treeing; Voltage stabilizer; Cable; Insulation;

   Sammanfattning : Voltage stabilizers are additives capable of inhibiting electrical treeing; a degradation mechanism for insulation materials subjected to strong divergent electric fields. The intended use is in cross-linked polyethylene (XLPE) high voltage power cable insulation where minute defects in the manufacturing process can give rise to the conditions needed for the initiation of treeing, which in the worst case scenario leads to failure of the insulation system with blackouts and expensive repairs as a consequence. LÄS MER

5. 4. Millimeter Wave Imaging and Phased Array Antennas for 5G and Aerospace Applications

   Författare :Jakob Helander; Teoretisk elektroteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 5G; phased array; Millimeter wave antenna arrays; millimeter wave imaging; Computational Electromagnetics; Non-destructive testing NDT ; compressive sensing;

   Sammanfattning : Phased array antennas are cornerstones in many proposed antenna solutions concerning the next generation of both airborne radar systems and wireless communication systems (5G). Additionally, millimeter wave (mm-wave) frequencies are expected to play an integral role in 5G, and are deemed well-suited for inspecting structural components used in the aerospace industry. LÄS MER

7. 5. Sensor and Signature Modeling for Aircraft Conceptual Development

   Författare :Carina Marcus; Peter Münger; Kristian Amadori; Peter Bull; Christopher Jouannet; Torleif Martin; Kelly Griendling; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : The aircraft design process has several phases, the first of which is conceptual design. In this phase, models describing an aircraft concept’s properties are used to evaluate its function and identify designs that meet given requirements. LÄS MER