Sökning: "urban system analysis"

Visar resultat 1 - 5 av 251 avhandlingar innehållade orden urban system analysis.

1. 1. Hydropower generator and power system interaction

   Författare :Johan Bladh; Urban Lundin; Rafael Escarela-Perez; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Amortisseur windings; applied voltage test; automatic voltage regulators; damper windings; damping torque; empirical modelling; equivalent circuits; excitation control; finite element method; hydropower generators; power system restoration; power system stability; synchronous machines; self excitation; shaft torque amplification; short circuit test; single machine infinite bus; slip test; standstill frequency response test; subsynchronous oscillations; synchronising torque; synchronous generators; torsional interaction.; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Sammanfattning : After decades of routine operation, the hydropower industry faces new challenges. Large-scale integration of other renewable sources of generation in the power system accentuates the role of hydropower as a regulating resource. LÄS MER

3. 2. Towards a Scenario-based Spatial Dynamic Modeling for Predicting Urban Land Use Change : Planning Tools and Comparative Analysis

   Författare :Zipan Cai; Vladimir Cvetkovic; Fredrik Gröndahl; Brian Deal; Stan Geertman; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; urbanization; planning support system; spatial dynamic model; urban land use change; spatial analysis; human-land interaction; socioeconomics; ecological systems; urban amenities; environmental impact assessment; what-if; decision-making; urbanisering; planeringsstödsystem; rumslig dynamisk modell; förändring av stadsmarkanvändning; rumslig analys; mänsklig-land interaktion; socioekonomi; ekologiska system; urbana bekvämligheter; miljökonsekvensbeskrivning; vad-om; beslutsfattande; Mark- och vattenteknik; Land and Water Resources Engineering;

   Sammanfattning : As global urbanization progresses, cities worldwide are growing in size, which leads to many economic, environmental, and management challenges. Recent advancements in spatial data analysis and algorithmic geography have also led to the development of various urban model-based planning support systems (PSS) for urban planning. LÄS MER

4. 3. Towards sustainable urban transportation : Test, demonstration and development of fuel cell and hybrid-electric buses

   Författare :Anders Folkesson; Per Alvfors; Peter Treffinger; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acceptance; analysis; auxiliary system; bus; Clean Urban Transport for Europe; concept; CUTE; demonstration; driver; drive cycle; duty cycle; energy flow; evaluation; fuel cell; heavy duty vehicle; hybrid management; hybrid vehicle; hydrogen; passenger; PEM; safety; Sankey diagram; series hybrid; sustainable; test; urban transport; vehicle simulation; acceptans; analys; hjälpaggregat; buss; Clean Urban Transport for Europe; koncept; CUTE; demonstration; körcykel; förare; energiflöde; utvärdering; bränslecell; tunga fordon; hybridsystemkontroll; hybridfordon; vätgas; passagerare; PEM; säkerhet; Sankey-diagram; seriehybrid; uthållig; hållbar; test; stadstransport; fordonssimulering; Vehicle engineering; Farkostteknik; Chemical engineering; Kemiteknik;

   Sammanfattning : Several aspects make today’s transport system non-sustainable: • Production, transport and combustion of fossil fuels lead to global and local environmental problems. • Oil dependency in the transport sector may lead to economical and political instability. LÄS MER

5. 4. The Auroral Large Imaging System : design, operation and scientific results

   Författare :Urban Brändström; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; Aurora; Artificial airglow; HF-pump enhanced airglow; Multistation measurements; Polar Stratospheric clouds; Radio-Induced optical emissions; Spectroscopic imaging observations; Tomography; Rymd- och plasmafysik; Space physics; Rymdfysik; rymdfysik; Space Physics;

   Sammanfattning : The Auroral Large Imaging System (ALIS) was proposed in 1989 by Åke Steen as a joint Scandinavian ground-based nework of automated auroral imaging stations. The primary scientic objective was in the field of auroral physics, but it was soon realised that ALIS could be used in other fields, for example, studies of Polar Stratospheric Clouds (PSC), meteors, as well as other atmospheric phenomena. LÄS MER

7. 5. Enhanced District Heating Technology : Maintaining Future System Feasibility

   Författare :Helge Averfalk; Sven Werner; Urban Persson; Mei Gong; Patrick Lauenburg; Kerstin Sernhed; Per-Olof Johansson Kallioniemi; Louise Ödlund; Högskolan i Halmstad; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : When heat demand and high temperature heat supply gradually decreases in the future, then it will effect district heating systems ability to compete on the heat market. A good way to mitigate less district heating feasibility is to operate systems with lower temperature levels and the most conceivable way to achieve lower temperature levels is to decrease return temperatures. LÄS MER