•A secondary succession model based on Ellenberg indicator values is proposed.•For each tree its actual vigour and height are calculated within annual time steps.•Each tree is appointed with the ...ecological neighbourhood, represented by a circle.•If two neighbourhoods intersect the tree with lower vigour eventually dies.•Tree competition triggers the changes in the species composition.
Over recent decades farmland abandonment has affected large areas of the landscape. To better predict the changes associated with this process, we developed a secondary succession model based on Ellenberg indicator values describing the ecological niche of a tree along environmental gradients. These values are compared with local ecological factors dependent on terrain conditions. The terrain is represented by a Digital Terrain Model, where the local conditions are represented by a light availability model, climate data, soil properties, and a combination of a water flow model and average annual rainfall data. Each tree in our model is associated with its immediate circular ecological neighbourhood and is treated individually from the seedling stage through to its decay. Each year, tree heights, actual vigour, and neighbourhood radii were calculated. When two radii intersected, the vigour of both trees was compared. The weaker of the two became dominated, leading to stress-related mortality. When a tree reached the adult stage, it produced seeds that established new seedlings that competed for light and nutrition. To start the simulation, the initial amount of seed was planted on bare ground. It was possible to monitor the succession phases either visually or statistically. 3D tree models were used to visualize a tree at any age, generating realistic landscape images useful for demonstrating long-term changes in the cultural landscape to non-experts. The results were compared with those from previous field studies in various areas of Slovenia. Apart from predicting landscape changes after farmland abandonment, the model can be used for forecasting the regeneration process after clearcutting or natural disasters.
In central Europe there are many backyard fruit growers who receive no proper education about fruit tree care. Their knowledge is mostly based on various handbooks and learning through trial and ...error. Such learning is slow and can even result in damage to the tree. To shorten the learning time, a new interactive teaching tool EduAPPLE has been developed based on the basic laws of apple tree ( Malus × domestica ) growth and training. Pruning, weighting, tying, and spreading can be interactively practiced over and over again without any danger to the actual trees. Training responses are immediately seen and are analogous to those of real trees. They are not only predetermined by a set of rules, but also calculated based on the changes the actions cause to the light interception of the tree. EduAPPLE enables high-quality views of trees and their light interception from all angles in real time and is designed for education regarding free-standing apple tree training (spindle). It can, therefore, be used in schools, universities, and other educational organizations, as well as by tree growers, including the large number of growers having only a few fruit trees.
Fire-fighters work under extremely stressful conditions where even their own lives and the lives of potential victims can be at stake. It is clear that there is no room for error and that extensive ...training is crucial in this regard. In Slovenia the greater part of the fire-fighting force consists of volunteers, whose training must be of the same quality as that of their career colleagues. Fire-fighters receive the bulk of their basic training in-house at their fire departments and by assisting at actual fires. More advanced training is received at special training facilities where the training is divided into a series of relatively short courses consisting of both theoretical and practical parts. This training culminates in a practical exam aimed at demonstrating their acquired knowledge. This article presents a new multimedia-based teaching tool SIN that has been designed for computer-supported theoretical knowledge delivery during fire-fighter training, where the emergency operations are visualised within environments familiar to the trainees. In order to save time the entire scenario is based on photographic images of real places. This application has already been successfully tested and is currently in use by the fire-fighter school at the Administration of the Republic of Slovenia for Civil Protection and Disaster Relief.
•SIN is a supporting application for knowledge transfer by fire-fighter training.•Application is suitable for short courses of volunteer fire-fighter training.•Fire-fighting procedures are presented in surrounding known by trainees.•SIN prepares efficiently trainees on the practical part of the training.
In the paper, we present a new architecture and implementation of a multi-agent system for university timetable generation. Agents as representatives of individual courses have the task of allocating ...the necessary human and technical resources through negotiation. We define the negotiation protocol and describe autonomous decisions of agents within the prescribed framework. The advantages of the multi-agent approach are a direct resolution of conflicts, strategic versatility of negotiation, and natural representation of some real-life problems.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
5.
Parallel alpha-beta algorithm on the GPU Strnad, D.; Guid, N.
Journal of computing and information technology,
12/2011, Letnik:
19, Številka:
4
Conference Proceeding, Journal Article, Paper
Recenzirano
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In the paper we present the parallel implementation of the alpha-beta algorithm running on the graphics processing unit (GPU). We compare the speed of the parallel player with the standard serial one ...using the game of reversi with boards of different sizes. We show that for small boards the level of available parallelism is insufficient for efficient GPU utilization but for larger boards substantial speed-ups can be achieved on the GPU. The results indicate that the GPU-based alpha-beta implementation would be advantageous for similar games of higher computational complexity (e.g. hex and go) in their standard form.
Current implicit blending techniques are mostly designed for use in surface modelling, where only boundaries of the object defined by the implicit primitives are important. In contrast, in volumetric ...implicit modelling the interior of the object is also significant, which requires different and more suitable techniques for combining implicit primitives. In this paper, we first discuss irregularities that occur using the current techniques. Then, a new technique for blending implicit primitives, especially appropriate in volumetric modelling (e.g., cloud modelling), is introduced. It overcomes these abnormalities and gives us better results than current techniques.
Parametric curves and surfaces are topics usually included in different disciplines, such as computer graphics, geometric modeling, computer-aided design (CAD), computer-aided geometric design ...(CAGD), etc. These rapidly emerging and extensive fields require students to understand a wide range of methods. In this context, SURFMOD, a teaching tool for parametric curves and surfaces, was constructed. SURFMOD enables interactive investigation, different quality analyses, and simultaneous studies of various methods using the same data, while, at the same time, adjusting the control parameters
A new approach in CAD system for designing shoes KOLMANIC, Simon; GUID, Nikola
CIT. Journal of computing and information technology/Journal of computing and information technology,
2003, Letnik:
11, Številka:
4
Journal Article, Paper
Recenzirano
Odprti dostop
The flattening of digitized surfaces is still very important in design of thin walled objects such as the airplane wings, parts of car bodies, textile products, and shoe uppers. Especially in shoe ...industry, the ability of quick respond to changing market needs is essential for successful competition. To give needed flexibility to a shoe designer, special CAD/CAM systems have been developed. Those systems are based on algorithms for surface reconstruction and surface flattening. In this article a fast algorithm for surface reconstruction and surface flattening is presented. Developable stripes are used to approximate a surface. In this way the surface can be flattened fast and without any distortions.
Genetic algorithms in animation of volumetric clouds Lipus, B.; Guid, N.
ITI 2002. Proceedings of the 24th International Conference on Information Technology Interfaces (IEEE Cat. No.02EX534),
2002
Conference Proceeding
Realistic modeling and animating clouds are ones of the hardest tasks in computer animation. There are different techniques used in computer graphics for representing clouds. Our work is based on ...volume-rendered implicit junction, for volumetric cloud modeling. Basically, implicit primitives are controlled by a modified particle system. We propose genetic algorithms for initialization of the particle system. They provide an alternative to traditional optimization techniques and are also useful in the key-frame animation. Additionally, we introduce some new ideas in volumetric clouds animation: advanced techniques for controlling a large collection of individual elements - flocks and autonomous behavior. Some properties of these techniques are also applicable in the cloud animation.
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