Sökning: "Narrow bipolar pulse"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden Narrow bipolar pulse.

1. 1. Interaction of Lightning Flashes with Wireless Communication Networks : Special Attention to Narrow Bipolar Pulses

   Författare :Mohd Riduan Ahmad; Vernon Cooray; Mahbubur Rahman; Rajeev Thottappillil; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Latitude; Lightning; Narrow bipolar pulse; Wireless network.; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

   Sammanfattning : In this thesis, the features of electric field signatures of narrow bipolar pulses (NBPs) generated by cloud flashes are investigated and their effects on wireless communication systems are studied. A handful amount of NBPs (14.5%) have been observed to occur as part of cloud-to-ground flashes in South Malaysia. LÄS MER

3. 2. Broadband and HF Radiation from Cloud Flashes and Narrow Bipolar Pulses

   Författare :Noor Azlinda Ahmad; Vernon Cooray; Farhad Rachidi; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lightning; Cloud Flashes; Narrow Bipolar Pulses; HF radiation; Other physics; Övrig fysik; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

   Sammanfattning : Remote measurement of electric field generated by lightning has played a major role in understanding the lightning phenomenon. Even though other measurements such as photographic and channel base current have contributed to this research field, due to practical reasons remote measurements of electric field is considered as the most useful tool in lightning research. LÄS MER

4. 3. Temporal and Wavelet Characteristics of Initial Breakdown and Narrow Bipolar Pulses of Lightning Flashes

   Författare :Mona Riza Mohd Esa; Vernon Cooray; Mahbubur Rahman; Farhad Rachidi; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Initial breakdown; Lightning flash; Narrow bipolar pulse; Temporal-Wavelet characterization; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

   Sammanfattning : Temporal and wavelet characteristics of initial breakdown pulses are meticulously studied especially during the earliest moment of lightning events. Any possible features during the earliest moment that may exist which lead to either negative cloud-to-ground (CG), positive cloud-to-ground, cloud or isolated breakdown flashes in Sweden are investigated. LÄS MER

5. 4. Broadband and HF radiation from cloud flashes and narrow bipolar pulses

   Författare :Noor Azlinda Ahmad; Uppsala universitet; []
   Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : Remote measurement of electric field generated by lightning has played a major role in understanding the lightning phenomenon. Even though other measurements such as optical, photographic, channel base current and thunder signatures have contributed in this regards, due to practical reasons remote measurements of electric field is considered as the most useful tool in lightning research. LÄS MER

7. 5. Engineered ion-bombardment as a tool in thin film deposition

   Författare :Rommel Paulo B. Viloan; Ulf Helmersson; Daniel Lundin; Rainer Hippler; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; HiPIMS; Bipolar HiPIMS; Ion-bombardment; Thin film;

   Sammanfattning : Energetic-ion bombardment has become an attractive route to modify the crystal growth and deposit high quality thin films. In high-power impulse magnetron sputtering (HiPIMS) where the discharge is characterized by a significant amount of ions of the sputter-ejected atoms, energetic-ion bombardment effects could not be underestimated. LÄS MER