83,590 research outputs found

    Review of recent research towards power cable life cycle management

    Get PDF
    Power cables are integral to modern urban power transmission and distribution systems. For power cable asset managers worldwide, a major challenge is how to manage effectively the expensive and vast network of cables, many of which are approaching, or have past, their design life. This study provides an in-depth review of recent research and development in cable failure analysis, condition monitoring and diagnosis, life assessment methods, fault location, and optimisation of maintenance and replacement strategies. These topics are essential to cable life cycle management (LCM), which aims to maximise the operational value of cable assets and is now being implemented in many power utility companies. The review expands on material presented at the 2015 JiCable conference and incorporates other recent publications. The review concludes that the full potential of cable condition monitoring, condition and life assessment has not fully realised. It is proposed that a combination of physics-based life modelling and statistical approaches, giving consideration to practical condition monitoring results and insulation response to in-service stress factors and short term stresses, such as water ingress, mechanical damage and imperfections left from manufacturing and installation processes, will be key to success in improved LCM of the vast amount of cable assets around the world

    Radiative Forcing: Climate Policy to Break the Logjam in Environmental Law

    Get PDF
    This article recommends the key design elements of US climate law. Much past environmental law has suffered from four design problems: fragmentation, insensitivity to tradeoffs, rigid prescriptive commands, and mismatched scale. These are problems with the design of regulatory systems, not a rejection of the overall objective of environmental law to protect ecosystems and human health. These four design defects raised the costs, reduced the benefits, and increased the countervailing risks of many past environmental laws. The principal environmental laws successfully enacted since the 1990s, such as the acid rain trading program in the 1990 Clean Air Act (CAA) Amendments and the 1996 Safe Drinking Water Act amendments, were consciously designed to overcome the prior design defects. New law for climate change should improve on the design of past environmental law, fostering four counterpart solutions to the prior design defects: cross-cutting integration instead of fragmentation, attention to tradeoffs instead of their neglect, flexible incentive-based policy instruments such as emissions trading in place of rigid prescriptive commands, and optimal instead of mismatched scale. This article advocates a design for U.S. climate policy that embodies these four design solutions. It proposes a policy that is comprehensive in its coverage of multiple pollutants (all GHGs), their sources and sinks; multiple sectors (indeed economy-wide); and multiple issues currently divided among separate agencies. It advocates explicit attention to tradeoffs, both benefit-cost and risk-risk (including both ancillary harms and ancillary benefits), in setting the goals and boundaries of climate policy. It advocates the use of flexible market-based incentives through an efficient cap-and-trade system, with most allowances auctioned along multi-year emissions reduction schedules that are reviewed periodically in light of new information. And it advocates matching the legal regime to the environmental and economic scale of the climate problem, starting at the global level, engaging all the major emitting countries (including the U.S. and China), and then implementing at the national and sub-national levels rather than a patchwork bottom-up approach. In so doing it addresses the roles of EPA regulation under the current CAA and of new legislation. It argues that among environmental issues, climate change is ideally suited to adopt these improved policy design features

    Airtightness of buildings — towards higher performance: Final Report — Domestic Sector Airtightness

    Get PDF
    This report constitutes milestone D11 — Final Report — Domestic Sector Airtightness of the Communities and Local Government/ODPM Project reference CI 61/6/16 (BD2429) Airtightness of Buildings — Towards Higher Performance (Borland and Bell, 2003). This report presents the overall conclusions and key messages obtained from the project through design assessments, construction observations, discussions with developers and pressurisation test results. It also summarises discussion on the airtight performance of current UK housing, the implementation and impact of current and future legislation, and identifies potential areas for future work

    Automotive Stirling Engine Development Program

    Get PDF
    Development test activities on Mod I engines directed toward evaluating technologies for potential inclusion in the Mod II engine are summarized. Activities covered include: test of a 12-tube combustion gas recirculation combustor; manufacture and flow-distribution test of a two-manifold annular heater head; piston rod/piston base joint; single-solid piston rings; and a digital air/fuel concept. Also summarized are results of a formal assessment of candidate technologies for the Mod II engine, and preliminary design work for the Mod II. The overall program philosophy weight is outlined, and data and test results are presented

    Hardware architecture implemented on FPGA for protecting cryptographic keys against side-channel attacks

    Get PDF
    This paper presents a new hardware architecture designed for protecting the key of cryptographic algorithms against attacks by side-channel analysis (SCA). Unlike previous approaches already published, the fortress of the proposed architecture is based on revealing a false key. Such a false key is obtained when the leakage information, related to either the power consumption or the electromagnetic radiation (EM) emitted by the hardware device, is analysed by means of a classical statistical method. In fact, the trace of power consumption (or the EM) does not reveal any significant sign of protection in its behaviour or shape. Experimental results were obtained by using a Virtex 5 FPGA, on which a 128-bit version of the standard AES encryption algorithm was implemented. The architecture could easily be extrapolated to an ASIC device based on standard cell libraries. The system is capable of concealing the real key when various attacks are performed on the AES algorithm, using two statistical methods which are based on correlation, the Welch’s t-test and the difference of means.Peer ReviewedPostprint (author's final draft

    Shaping the Global Arena: Preparing the EU Emissions Trading Scheme for the post-2012 Period. CEPS Task Force Reports No. 61, 6 March 2007

    Get PDF
    Having been underway for more than two years, the review of the EU Emissions Trading Scheme (EU ETS) is entering a decisive phase with the European Commission’s recent announcement that it will table formal proposals in the second half of 2007. Based on an assessment of the EU ETS, this new CEPS Task Force Report tests the performance of four different design models (a cap-and-trade system based on free allocation, benchmarks, auctioning and a credit-and-baseline system) against 10 criteria under three headings: environmental effectiveness, economic efficiency and the contribution of the ETS to achieving long-term climate change policy objectives. Based on this assessment, the report makes a number of recommendations in the area of allocation, creation of investment incentives and the merits of including new sectors and new gases. The report also addresses the particular challenge of completing the EU ETS review before a global post-2012 agreement can be reached, i.e. the EU ETS will be reviewed against an unknown global context
    • …
    corecore