Search for dissertations about: "positive leader"

Showing result 1 - 5 of 28 swedish dissertations containing the words positive leader.

  1. 1. Features of the Electric Fields Generated by Lightning with Special Attention to Positive Ground Flashes

    Author : Dalina Johari; Vernon Cooray; Mahbubur Rahman; Fridolin Heidler; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; positive ground flashes; preliminary breakdown pulses; multiple-trains PBPs; positive leader; bidirectional leader; negative leader branch; subsequent return strokes; distant lightning; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Abstract : This thesis focuses on the main processes in positive ground flashes and the distant lightning environment for both positive and negative ground flashes. It presents the characteristics of the preliminary breakdown pulses (PBPs), the characteristics of the electric field pulses observed during leader propagation, and the characteristics of the electric fields produced by the first and the subsequent return strokes. READ MORE

  2. 2. Unravelling the social and ecological implications of policy instruments for biodiversity governance

    Author : Niak Sian Koh; Thomas Hahn; Claudia Ituarte-Lima; Wijnand Boonstra; Johanna Alkan Olsson; Henrik Josefsson; Grace Wong; Stockholms universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biodiversity offsets; commensurability; commodification; Convention on Biological Diversity; human rights; No Net Loss; Sustainability Science; vetenskap om hållbar utveckling;

    Abstract : Biodiversity losses are occurring at an unprecedented rate, with ongoing environmental degradation at the expense of expanding economic activities. A transformative change is needed away from business-as-usual development and towards prioritizing the conservation and sustainable use of biodiversity. READ MORE

  3. 3. Numerical modelling of positive electrical discharges in long air gaps

    Author : Oscar Diaz; Vernon Cooray; Raul Montano; Uppsala universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high voltage techniques; numerical modeling; electrical discharge in gases; streamer mechanism; leader channel; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Abstract : This dissertation deals with research on the numerical modelling of electrical discharges in laboratory long air gaps excited with positive switching impulses. It begins with the preliminary work of several scientists during the last decades, making a detailed analysis of different approaches for modelling all the stages in a full discharge. READ MORE

  4. 4. Numerical Simulations of Long Spark and Lightning Attachment

    Author : Liliana Arevalo; Vernon Cooray; Dan Windmar; Uppsala universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; breakdown; discharge; leader channel; lightning attachment; negative discharge; positive discharge; streamer; Electrical engineering; Elektroteknik; Engineering Science with specialization in Atmospheric Discharges; Teknisk fysik med inriktning mot atmosfäriska urladdningar;

    Abstract : The research work presented here is concerned with numerical simulations of two different electrical phenomena: Long gap electrical discharges under switching impulses and the lightning attachment process associated with positive upward leaders. The development of positive upward leaders and the progression of discharges in long gaps are attributable to two intertwined physical phenomena, namely, the leader channel and the streamer zone. READ MORE

  5. 5. Make the Future a Part of Today : Awaken Long-term Thinking in Quality Management Practices

    Author : Anna Mårtensson; Pernilla Ingelsson; Kristen Snyder; Peter Cronemyr; Mittuniversitetet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Long-term thinking; future; quality management; sustainable development; leader; leadership; culture;

    Abstract : Individuals and organisations need to consider the future since actions taken today will have implications for the future. Long-term thinking as a concept encompasses consideration of the future and is identified in both quality management and sustainable development. READ MORE