Search for dissertations about: "switching field"

Showing result 1 - 5 of 180 swedish dissertations containing the words switching field.

2. 1. Essays on Field Experiments and Impact Evaluation

   Author : Remidius Denis Ruhinduka; Göteborgs universitet; []
   Keywords : SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; adaptation to climate change; ambiguity; artefactual field experiment; behavioraleconomics; charcoal; credit; deforestation; endogenous switching regression; field experiment; guilt; honesty; impact evaluation; kindness; liquidity constraint; LPG stoves; rice marketing; risk preferences; system of rice intensification; Tanzania; time preferences;

   Abstract : Paper 1: Improving Welfare Through Climate-Friendly Agriculture: The Case of the System of Rice Intensification We use rich survey data to investigate the economic impact of a climate-friendly rice farming method known as the system of rice intensification (SRI) on the welfare of rain-dependent small-holder farmers in Tanzania. SRI reduces water consumption by half, which makes it a promising farming system in the adaptation to climate change in moisture constrained areas, and it does not require flooding of rice fields, resulting in reduced methane emissions. READ MORE

4. 2. Voltage Transients in the Field Winding of Salient Pole Wound Synchronous Machines : Implications from fast switching power electronics

   Author : Roberto Felicetti; Urban Lundin; Jon Kjellin; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; apparent resistance; cable modeling; current control; transmission line model; eddy currents; field winding; frequency analysis response; Fourier Transform; impedance mismatch; main inductance; overvoltage; parasitic capacitance; partial discharge; quality factor; ringing; slew rate; stray inductance; voltage gradient; winding resonance frequency;

   Abstract : Wound Field Synchronous Generators provide more than 95% of the electricity need worldwide. Their primacy in electricity production is due to ease of voltage regulation, performed by simply adjusting the direct current intensity in their rotor winding. READ MORE

5. 3. Characterization of domain switching and optical damage properties in ferroelectrics

   Author : Junji Hirohashi; Fredrik Laurell; Ady Arie; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; quasi-phase matching; ferroelectric domains; stoichiometric LiNbO3; stoichiometric LiTaO3; KTiOPO4; KNbO3; polarization switching; periodic electric field poling; optical damages; Optical physics; Optisk fysik;

   Abstract : Nonlinear optical frequency conversion is one of the most important key techniques in order to obtain lasers with wavelengths targeted for specific applications. In order to realize efficient and tailored lasers, the quasi-phase-matching (QPM) approach using periodically-poled ferroelectric crystals is getting increasingly important. READ MORE

6. 4. Cultural and socio-political development in south Etruria. : The Biedano region in the 5th to 1st centuries BC

   Author : Hampus Olsson; Antikens kultur och samhällsliv; []
   Keywords : HUMANIORA; HUMANITIES; Etruscans; Etruscology; Blera; Biedano region; ager Bleranus; Rome; Roman Republic; Roman archaeology; Romanisation; Globalisation; Bilingualism; code-switching; Imperialism; Etruscan prosopography; Etruscans; Etruscology; Etruscan prosopography; Blera; Biedano region; ager Bleranus; South Etruria; Etruria meridionale; Rome; Roman Republic; Romanisation; Imperialism; Globalisation; Bilingualism; Code-switching; Roman archaeology; Etruscan archaeology;

   Abstract : The town of Blera is situated in the southern parts of Etruria and has a history spanning more than 2,500 years. Its location between the two important Etruscan cities of Tarquinii and Caere has meant that Blera, for the entire Etruscan period (c. 750–50 BC), alternatively has found itself in either city’s sphere of interest. READ MORE

7. 5. Self-Switching Diodes for Zero-Bias Terahertz Detection

   Author : Andreas Westlund; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; self-switching diode; noise-equivalent power; SSD; graphene; zero-bias; InAs; InGaAs; terahertz; detector;

   Abstract : The self-switching diode (SSD) has been investigated as a potential terahertz detector in recent years. The SSD accomplishes a non-linear current-voltage relation through a field-effect, which enables detection at zero bias from microwave up to terahertz frequencies. In this work, SSDs were realised in two new materials; InAs and graphene. READ MORE