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The Benefits of Free Rhinoterrain 2 0 For Rhino 5 0: Robust Triangulation, Orthophoto Draping, and M



This is a reverse engineering plugin that lets users convert digitized objects from non-contact 3D scanners to CAD models. The free version lets you construct 25 shapes rather than offering a time limit trial. Obviously these limitations are removed if you decide to purchase the full license.




Free Rhinoterrain 2 0 For Rhino 5 0




Rhinos journey began way back in 1990 when Robert McNeel & Associates created a new graphics and Cad platform. What set it apart was that at its core it was based on the NURBS mathematical model. This enables the exact creation of curves and freeform surfaces. Rhino has its own file format (.3DM) which is ideal for the exchange of this NURBS geometry. They also developed the openNURBS 3DM file format to allow for open sharing of this type of geometry too. Rhino continues to go from strength to strength and is in constant development.


In highly heterogeneous landscapes, basic habitat use/availability models may overestimate carrying capacities, especially when areas of preferred habitat are isolated by terrain that is energetically expensive to traverse [19]. This can be of particular importance to territory holding species such as the white rhinoceros, as the amount of total accessible attractive habitat may give a better indication of territory quality than total territory size or amount of high value habitat per se [8]. To date very little research has been conducted on terrain preference in white rhinoceros, although Perrin and Brereton-Stiles [20] did record selection against steeper gradients in a study conducted in Hluhluwe-Umfolozi Game Reserve.


In small game reserves, reserve managers should be aware of the degree of overlap territory owning (F-class) males will tolerate from sub-adult (E-class) males in both their core and home ranges, as this acts as a surrogate for the likelihood of injuries sustained from territorial battles. These battles prove costly to reserve managers as they must provide veterinary care for the injured animals, with the injuries potentially impacting upon future off-take of surplus animals. As a consequence we considered the territorial relationship between both E and F-class males. Rather unsurprisingly, the F-class males did not tolerate any E-class males within their core (50% kernel) territory but did allow E-class males into their overall home (95% kernel) range (Mean = 40%, SD = f 25%). Interestingly, although the reserve has been very successful in terms of youngsters born, the rhinoceros density in the reserve is 0.15 rhino per km2 (based on 2012 census of 58 rhinoceros) and is considerably lower than in other reserves e.g. Hluhluwe-Umfolozi which had > 3 rhinoceros per km2 [20), whilst both Kruger National Park and Ndumu both supported >0.5 rhinoceros/km2 [21, 22]. Here we note that the density is kept low by the reserve management team (who translocate surplus animals) but it does raise the question as to why such low densities are not resulting in larger individual territories, particularly for females? We propose that this is a function of the heterogeneous nature of the terrain mosaic of the reserve and that this would be a careful consideration when planning to establish new populations in similar sized vegetation and terrain comprised reserves. In addition to this, the plentiful all year round supply of water across the reserve negates the requirement for an individual to travel long distances to find water, thus decreasing the size of the home territory[45].


Due to the presence of a steep sided valley that transects the reserve which the rhinoceros would be very unlikely to negotiate, we analysed terrain selection in two distinct sub-units (north and south). In both the north and south, males and females showed a strong preference for open grassland and avoidance of hill slope and riparian terrains. Hill slopes would be very energetically expensive to traverse, so even if there was spare attractive territory beyond the hill slopes, females would be unlikely to occupy them, and without females, they would offer very little value to a male territory holder. Similarly, riparian terrains in the reserve tend to be step-sided, presenting the rhino with similar access conditions as encountered on hill slopes. Both hill slope and riparian terrain types tend to be the more heavily wooded and our results compare favourably with that of White et al [5], who demonstrate that dense and medium woodland proved unattractive in terms of habitat composition, making up less than 10% of overall territory for both males and females. That said, direct comparison between our results and those from previous authors proved difficult, as the majority of previous work has utilised habitat rather than terrain descriptors. This was particularly evident when comparing our findings for terrain preference against the findings of White et al [5] who indicate that open woodland accounted for over 60% of habitat composition in male and female rhinoceros territories, whilst this research indicates open grassland and saddle terrains to be particularly favoured.


Both males and females demonstrated complete avoidance of valley bottom in the south. This a consequence of the very small and highly fragmented units of this terrain type and the sheer nature of the immediate terrain adjacent to the valley bottom making it difficult for the rhinoceros to traverse. In the north, where valley bottom terrain was relatively abundant, the terrain type was still not considered preferential by both genders, with selectivity values indicating no preference in every instance.


We would like to thank the lodge owners of Welgevonden Game Reserve for access to their properties and for their support for this project. We are indebted to the conservation management staff of the reserve in general and Gerhardt Lorist in particular, for provision of on the ground knowledge of individual rhino identification and distribution. This study was supported by Operation Wallacea. We would like to thank their volunteers who assisted in the field. 2ff7e9595c


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