It is shown that the only Killing vector fields admitted by the Kerr-Newman spacetime are those corresponding to the time independence and axial symmetries, and that the only conformal vector fields ...or projective collineations admitted by the Kerr-Newman spacetime are the Killing vector fields. In addition, it is shown that the Kerr-Newman spacetime admits no covariantly constant vector fields or recurrent vector fields, and is of holonomy type R15. It is also established that any Weyl conformal collineation, Weyl projective collineation or curvature collineation admitted by the Kerr-Newman spacetime are the Killing vector fields, and that the only Ricci or matter collineations admitted by the Kerr-Newman spacetime are again Killing vector fields. Finally, some analogous results are established for the Reissner-Nordström spacetime.
A recently proposed analytical wake model for a horizontal axis utility scale wind turbine is revisited, and revised and improved. The model is based upon conservation of momentum in the context of ...actuator disc theory, and the assumption of a distribution of the double-Gaussian type for the velocity deficit in the wake. The model is developed and improved and reveals characteristics of the wind turbine wake velocity deficit for the full wake, including the near-wake to within close proximity of the wind turbine rotor. Full 2-dimensional model fitting to lidar wake measurement data obtained from a 5 MW utility scale wind turbine is carried out for the full range of inflow wind velocities of primary interest. Such a full wind turbine wake model has the potential to facilitate analytic calculations within the wind turbine wake region, and the potential to improve understanding of wind turbine aerodynamics.
•Double-Gaussian analytical wake model for a horizontal axis wind turbine.•Wake model validation for utility scale wind turbine.•Characteristics of wind turbine wake velocity deficit modelled.
Social science methodologies are increasingly used by conservation organisations to improve social‐ecological outcomes. However, ethnographic approaches seeking to understand organisations themselves ...and how organisational culture impacts biodiversity and social justice are rarely discussed. By exploring previous studies of the methodological considerations of organisational ethnography in conservation, we provide conservationists and ethnographers with an empirically grounded understanding of the opportunities, challenges and underlying ethical considerations of this approach.
We conducted a scoping review of a disparate body of literature where ethnographers were embedded in conservation organisations and discussed their methodology, identifying 26 studies for analysis. We then extracted information on key themes relevant to methodological process and uptake.
Our review found such research spanned the globe, with a broad range of methodological and ethical considerations related to how ethnographers and conservationists interact. For example, organisational ethnography was perceived as valuable by conservationists as it allowed tracking progress toward internal goals such as diversification of staff and providing moral and emotional support and valuable information for transforming organisational practices. However, conservationists also worried about ethnographers' presence in their organisations. A key methodological challenge we identify, corroborating with the literature, is how ethnographers can benefit organisations while supplying critique.
Based on the results, we provide recommendations and areas of reflection for conservation organisations and ethnographers. Mainstreaming organisational ethnography through attention to certain methodological considerations can be beneficial for the future of conservation organisations and the biodiversity and people they impact.
The Newman-Janis algorithm is supplemented with a null rotation and applied to the tensors of the Reissner-Nordström spacetime to generate the metric, Maxwell, Ricci and Weyl tensors for the ...Kerr-Newman spacetime. This procedure also provides a mechanism whereby the Carter Killing tensor arises from the geodesic angular momentum tensor of the underlying Reissner-Nordström metric. The conformal Killing tensor in the Kerr-Newman spacetime is generated in a similar fashion. The extended algorithm is also applied to the Killing vectors of the Reissner-Nordström spacetime with interesting consequences. The Schwarzschild to Kerr transformation is a special case.
Combating the surge of illegal wildlife trade (IWT) devastating wildlife populations is an urgent global priority for conservation. There are increasing policy commitments to take action at the local ...community level as part of effective responses. However, there is scarce evidence that in practice such interventions are being pursued and there is scant understanding regarding how they can help. Here we set out a conceptual framework to guide efforts to effectively combat IWT through actions at community level. This framework is based on articulating the net costs and benefits involved in supporting conservation versus supporting IWT, and how these incentives are shaped by anti‐IWT interventions. Using this framework highlights the limitations of an exclusive focus on "top‐down," enforcement‐led responses to IWT. These responses can distract from a range of other approaches that shift incentives for local people toward supporting conservation rather than IWT, as well as in some cases actually decrease the net incentives in favor of wildlife conservation.
Celebrities are frequently used in conservation marketing as a tool to raise awareness, generate funding and effect behaviour change. The importance of evaluating effectiveness is widely recognised ...in both marketing and conservation but, to date, little research into the effectiveness of celebrity endorsement as a tool for conservation marketing has been published. Using a combination of interviews and an online choice survey instrument, we investigated the extent to which a sample of UK-based conservation organisations, and other charities, evaluate their own usage of celebrity endorsement, and then carried out an experimental evaluation of a hypothetical marketing campaign. This experiment compared participants' willingness-to-engage (WTE) with, and recall of, a conservation message presented in versions of an advert featuring one of three prominent UK celebrities (David Beckham, Chris Packham or HRH Prince William) or a non-celebrity control treatment (featuring Crawford Allan, a director of TRAFFIC USA). We find that the organisations we interviewed did not routinely evaluate their marketing campaigns featuring celebrities. Furthermore, our experiment provides evidence that celebrity endorsement can produce both positive and negative effects. Participants were more willing to engage when presented with an advert featuring one of the three celebrities than the non-celebrity control, and WTE varied according to the characteristics of the celebrity and the respondent. However, celebrities were less effective at generating campaign message recall than non-celebrities. These findings suggest that celebrity endorsement should be used carefully. Further work is required to fully understand the role celebrity endorsers can play in conservation but, drawing on best practice from the field of marketing, this study introduces an approach to evaluation which could be applied more widely to improve the effectiveness of conservation marketing.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This article reports on an open-source ontology that has been developed to establish an industry-wide consensus on wind lidar concepts and terminology. The article provides an introduction to wind ...lidar ontology, provides an overview of its development, and provides a summary of its aims and achievements. The ontology serves both reference and educational purposes for wind energy applications and lidar technology. The article provides an overview of the creation process, the outcomes of the project, and the proposed uses of the ontology. The ontology is available online and provides standardisation of terminology within the lidar knowledge domain. The open-source framework provides the basis for information sharing and integration within remote sensing science and fields of application.
Abstract Terrestrial and marine protected areas have long been championed as an approach to biodiversity conservation. For protected areas to be effective, equitable and inclusive, the involvement of ...local residents in their management and governance is considered important. Globally, there are many approaches to involving local residents in protected area law enforcement. However, opportunities for comparing different approaches have been limited by the lack of a clear common framework for analysis. To support a more holistic understanding, we present a framework for analysing the contributions of local residents to protected area law enforcement. Informed by a review of the literature and discussions with conservation practitioners, the framework comprises five key dimensions: (1) the different points in the enforcement system at which local residents are involved, (2) the nature of local participation in decision-making, (3) the type of external support provided to local residents, (4) the different motivating forces for participation, and (5) the extent to which local participation is formalized. We apply the framework to three real-world case studies to demonstrate its use in analysing and comparing the characteristics of different approaches. We suggest this framework could be used to examine variation in local participation within the enforcement system, inform evaluation and frame constructive discussions between relevant stakeholders. With the global coverage of protected areas likely to increase, the framework provides a foundation for better understanding the contributions of local residents to protected area law enforcement.
Fencing is a ubiquitous part of the landscape across the Great Plains of North America. This can fragment habitats and reduce the ability of wildlife to move between patches. A relatively novel ...conservation tool aimed at mitigating these impacts is the use of wildlife‐friendly fencing. However, there is still an incomplete understanding as to how this tool affects ungulate movement and whether it increases habitat connectivity across barriers. Using camera trap data from three properties across the American Prairie Reserve, Montana, we investigated the effects of fencing on four ungulate species. Averaged across species and demographics, this wildlife‐friendly fencing design increased the probability that ungulates successfully crossed a fence by 33% and reduced the time taken to cross by 54%, but has limited effects on species' crossing behavior. Responses to the wildlife‐friendly fencing differed between species, sex, and age class. The greatest improvement in permeability was detected for mule deer, females, and juvenile groups. Yet, permeability remained lowest for elk, juveniles, and males overall at both fence types. Understanding these differences between groups is important when improving or selecting fence designs, and we highlight vulnerable groups that may require further study when implementing this conservation tool.