The province of Almeria presents a mosaic of ecological conditions which has given rise to an extremely rich natural patrimony. Combining a number of criteria aiming at the preservation of endangered species with chor...
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The province of Almeria presents a mosaic of ecological conditions which has given rise to an extremely rich natural patrimony. Combining a number of criteria aiming at the preservation of endangered species with chorological information is an efficient way of determining the floristically valuable areas at a regional level. Our research aims at defining the most valuable sites in Almeria as far as flora is concerned in order to subsequently compare the results with the Network of Protected Natural Areas of Andalusia (RENPA). We have taken as our fundamental reference a very detailed and geo-referenced data base with all the catalogued taxa occurring in Almeria. The implementation both of several algorithms for the automatic selection of natural reserves and of the indexes of Importance and Responsibility provides a set of solutions comparable with the RENPA proposals. Our results reveal that there are still unprotected enclaves with species whose conservation is crucial if we wish to safeguard the highest degree of diversity. A network of micro-reserves would help not only to protect these extremely valuable botanical areas but also to bring their importance to the attention of the general public.
Visibility determination is one of the oldest problems in computer graphics. The visibility, in terms of back-to-front polygon visibility ordering, is determined by updating a priority list as the viewpoint moves. A n...
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Visibility determination is one of the oldest problems in computer graphics. The visibility, in terms of back-to-front polygon visibility ordering, is determined by updating a priority list as the viewpoint moves. A new list-priority algorithm, utilizing a property of Voronoi diagrams, is proposed in this paper. The operation is in two phases. First, in a pre-processing phase the scene is divided into Voronoi cells. A sub-list associated with each cell contains references to those polygons that intersect with it. The polygons are assigned a fixed set of view-independent priority orders within the cluster. Last, an interactive phase sorts the clusters according to the depth value of each Voronoi site. The most time-consuming work is performed during the pre-processing phase that only has to be executed once for the scene. Since all the polygons in a cell are pre-computed to obtain the fixed priority order within the cluster, a relatively simple task is left in the interactive phase, which is only to sort the clusters repeatedly when the viewpoint is changed. This method contains performance benefits that make it better shaped than previous BSP based methods.
A scheduling algorithm called queue length control is proposed to ensure different quality in each of the traffic flows at a network node. This algorithm determines the control parameters (average queue length and its...
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A scheduling algorithm called queue length control is proposed to ensure different quality in each of the traffic flows at a network node. This algorithm determines the control parameters (average queue length and its standard deviation) for a queue in advance (and off-line) by using the M/G/1 model based on the delay target of each queue and then schedules based on these control parameters for each queue. A simulation compares this algorithm to other algorithms and demonstrates that the delay target of each traffic flow could be achieved over a broad range. When the control parameters are determined, although the actual packet length distribution and the packet arrival distribution are assumed to be different, a certain level of performance can be achieved. in other words, the presence of superior robust control characteristics is demonstrated. (C) 2003 Wiley Periodicals, Inc.
This paper presents a method for minimizing the total elapsed time spent by n tasks running on m differents processors working in parallel. ?he developed algorithm not only minimizes the total elapsed time but also re...
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ISBN:
(纸本)0819425885
This paper presents a method for minimizing the total elapsed time spent by n tasks running on m differents processors working in parallel. ?he developed algorithm not only minimizes the total elapsed time but also reduces the idle time and waiting time of in-process tasks. This condition is very important in some applications of computer vision in which the time to finish the total process is particularly critical -quality control in industrial inspection, real-time computer vision, guided robots, .... The scheduling algorithm is based on the use of two matrices, obtained from the precedence relationships between tasks, and the data obtained from the two matrixes. The developed scheduling algorithm has been tested in one application of quality control using computer vision. The results obtained have been satisfactory in the application of different image processing algorithms.
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