1,689 research outputs found
The quantification of wind turbulence by means of the fourier dimension
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?
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
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A Data-Driven Design Evaluation Tool for Handheld Device Soft Keyboards
Thumb interaction is a primary technique used to operate small handheld devices such as smartphones. Despite the different techniques involved in operating a handheld device compared to a personal computer, the keyboard layouts for both devices are similar. A handheld device keyboard that considers the physical capabilities of the thumb may improve user experience. We developed and applied a design evaluation tool for different geometries of the QWERTY keyboard using a performance evaluation model. The model utilizes previously collected data on thumb motor performance and posture for different tap locations and thumb movement directions. We calculated a performance index (PITOT, 0 is worst and 2 is best) for 663 designs consisting in different combinations of three variables: the keyboard's radius of curvature (R) (mm), orientation (O) (°), and vertical location on the screen (L). The current standard keyboard performed poorly (PITOT = 0.28) compared to other designs considered. Keyboard location (L) contributed to the greatest variability in performance out of the three design variables, suggesting that designers should modify this variable first. Performance was greatest for designs in the middle keyboard location. In addition, having a slightly upward curve (R = −20 mm) and orientated perpendicular to the thumb's long axis (O = −20°) improved performance to PITOT = 1.97. Poorest performances were associated with placement of the keyboard's spacebar in the bottom right corner of the screen (e.g., the worst was for R = 20 mm, O = 40°, L = Bottom (PITOT = 0.09)). While this evaluation tool can be used in the design process as an ergonomic reference to promote user motor performance, other design variables such as visual access and usability still remain unexplored
A call for a wider perspective on sustainable forestry: introduction to the Special Issue on The Social Impacts of Logging
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
Towards more inclusive community landscape governance:Drivers and assessment indicators in northern Ghana
Community-based approaches to landscape governance are considered more legitimate, equitable, and inclusive ways to manage natural resources and more effective in achieving conservation and livelihood goals than centralised and top-down approaches. In Ghana, the Wildlife Division of the Forestry Commission devolved decision-making authority over natural resources through the Community Resource Management Area (CREMA) governance system. While there is a growing body of literature on the CREMA governance model, few studies have examined the inclusiveness of its decision-making processes. This study aims to fill this gap by identifying the drivers that hinder or foster the inclusiveness of community governance in the Western Wildlife Corridor of northern Ghana and developing a set of inclusivity assessment indicators. Based on data collected through key informant interviews, focus group discussions, and observations, we found that several stakeholder groups remain at the margins of the CREMA governance system and feel excluded, particularly Fulani herders, women, and youth. Based on our findings and the literature, we present a set of assessment indicators for inclusive CREMA governance. However, these indicators are unlikely to be fully met because of persisting socio-cultural barriers and power asymmetries. We argue that measures such as capacity building, empowering marginalised social groups, promoting their participation in decision-making, and a bottom-up approach towards creating CREMAs are needed to improve the inclusiveness of CREMA governance. Beyond the CREMAs, the inclusivity indicators developed in this study have broad applicability to environmental and landscape governance
The International Forestry Review: special issue: the social impacts of logging
Global Challenges (FSW
Note and Comment
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
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