Technical activities At the moment D1 includes the following active working groups:Ref. Number - Title / Convenor CSAG D1 - Strategic and Customer Related Advisory Group / J. Smit AG D1.01 - Liquid and Liquid Impregnated Insulation Systems/ L. Lundgaard AG D1.02 - High Voltage and Current Testing and Diagnostic/ M. Muhr AG D1.03 - Insulating Gases / U. Schichler AG D1.04 - Solid Materials / J. Densley WG D1.17 - HV Asset Condition Assessment Tools, Data Quality and Expert Systems / E. Gulski WG D1.19 - Solid Insulation Endurance under Repetitive Transient Voltages / J. Holboell WG D1.20 - Water Tree Detection in XLPE insulation / J. Densley WG D1.23 - HVDC ageing, diagnostics and accelerated life testing of polymeric materials / G.C. Montanari WG D1.24 - Potential of Polymer Nanocomposites as Electrical Insulation for Highly Stressed Insulation Material in AC and DC Application / T. Tanaka WG D1.25 - Application Guide for PD Detection in GIS using UHF or Acoustic Methods / U. Schichler WG D1.26 - Basic Principles to Determinate Methane Content of Cross-linked Solid Insulation of MV and HV Cables / S. Pelissou WG D1.27 - Material Properties for New and Non-ceramic Insulation/ J. Kindersberger WG D1.29 - Partial Discharges in Transformers / J. Fuhr WG D1.30 - Oxidation Stability of Transformer Insulating Oils / I. Höhlein WG D1.31 - Dielectric Performance of insulating liquids for transformers / L. Lundgaard WG D1.32 - Progress in DGA techniques and diagnoses / M. Duval WG D1.33 - High Voltage Test and Measuring Techniques / M. Muhr WG D1.34 - Condition assessment for oil-impregnated insulation used in ac cables / S. Cherukupalli WG D1.35 - Performance of high-voltage and high-current measurement systems for high voltage testing / Y. Li WG D1.36 - Special requirements for dielectric testing of ultra high voltage (UHV) equipment / U. Riechert WG D1.38 - Emerging Test Techniques Common to High Temperature Superconducting (HTS) Power Applications / H. Okubo WG D1.39 - Methods for Diagnostic/Failure Data Collection and Analysis / P. Morshuis WG D1.42 - Radiation Ageing of Polymeric Insulating Materials / T. Okamoto