1,664 research outputs found

    The quantification of wind turbulence by means of the fourier dimension

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    Signal Processing within the frequency domain has long been associated with electrical engineering as a means to quantify the characteristics of voltage/current waveforms. Historically, wind speed data (speed/direction) have been captured and stored as statistical markers within a time series description. This form of storage, while cumbersome, is applicable in wind regimes that are relatively laminar. In urban environments, where the associated topographies and building morphologies are heterogeneous, wind speeds are highly turbulent and chaotic. In such environments and with particular reference to wind energy, time series statistics are of limited use, unless the generic probability distribution function (PDF) is also considered. Furthermore, the industry standard metric that quantifies the turbulent component of wind speed, Turbulence Intensity (TI), is computationally cumbersome and resource intensive. An alternative model to quantify turbulence is proposed here. This paper will describe how Fourier dimension modelling (Df), through linkage with the Weibull probability density function, can quantify turbulence in a more efficient manner. This model could potentially be developed to facilitate urban wind power prediction and is relevant to the planning and development considerations within the built environment

    Finding alternatives to swidden agriculture:Does agroforestry improve livelihood options and reduce pressure on existing forest?

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    Swidden cultivation can contribute to deforestation and land degradation, which can subsequently result in a number of serious environmental problems. This paper examines the economic and social potential of agroforestry systems and the barriers to their widespread adoption, as a land use alternative to swidden cultivation, which may potentially help protect local forest. The Gunung Salak valley in West Java, Indonesia is presented as a case study. Based on farmers� and experts� assessment, costs and benefits have been estimated, which show that the two investigated agroforestry systems have higher net present value and benefit-cost ratio (B/C) than the two swidden cultivation systems. Tree ownership also creates more permanent rights to farmland and is prestigious in the community. Agroforestry products (fruit, vegetables etc.) have high monetary value and help strengthen social cohesion when shared with neighbors. However, farmers are reluctant to implement agroforestry. Stated reasons are related to both culture and capacity. Farmers practicing agroforestry are less involved in forest clearing and forest products collection than swidden farmers indicating that it may contribute positively to conservation of local forests. Increasing the adoption of agroforestry farming in the study area will require support to overcome capacity constraint

    A call for a wider perspective on sustainable forestry: introduction to the Special Issue on The Social Impacts of Logging

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    Global demand for timber is projected to grow and much of this timber will continue to be sourced from natural forests. As these forests, particularly in the tropics, tend to be inhabited by the world's most marginalized communities, the social impacts of logging require more attention within policy, practice and research. This Introduction to the Special Issue of International Forestry Review on The Social Impacts of Logging compiles evidence that the overwhelmingly negative social impacts of logging are systemic. As logging companies fail to fulfill their social obligations, and elite capture is common, the extent to which local communities benefit from logging operations is minimal, while long-term, harmful effects on livelihoods, social fabric and safety are severe. Logging operations reinforce and often exacerbate pre-existing inequities, particularly for women and Indigenous people. Weak governance, a lack of transparency and poor participation procedures partially explain this unfavourable situation. However, logging will only achieve better social outcomes if underlying power-imbalances are tackled.Horizon 2020(H2020)748242Global Challenges (FSW

    Note and Comment

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    The Writ of Prohibition - Procedural Delay - A disheartening recrudescence of procedural red-tape is found in a recent decision of the Supreme Court of Ohio. A contest arose over the jurisdiction of the Public Service Commission to fix telephone rates in Cleveland. The Commission was engaged in a determination as to the reasonableness of a schedule of rates filed by the telephone company, when a petition was filed in the Common Pleas Court for an injunction against the charging of rates other than those fixed by a city ordinance

    The trade offs in multi-purpose land use

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