A Stable and Invariant Three-polar Surface Representation: Application to 3D Face Description
Jribi, Majdi; Ghorbel, Faouzi
2014 - anglický In this paper, we intend to introduce a new curved surface representation that we qualify by three-polar. It is constructed by the superposition of the three geodesic potentials generated from three reference points of the surface. By considering a pre-selected levels set of this superposition, invariant points are obtained. A comparative study between this representation and the unipolar one based on the level curves around one reference point is established in the sense of the stability under errors on the reference points positions. The three-polar representation is applied, finally, for 3D human faces description. Its accuracy is performed in the mean of the Hausdorff shape distance. Klíčová slova: reprezentace povrchu; 3D popis; obličej; surface representation; 3D description; face Plné texty jsou dostupné v digitálním repozitáři ZČU. A Stable and Invariant Three-polar Surface Representation: Application to 3D Face Description

In this paper, we intend to introduce a new curved surface representation that we qualify by three-polar. It is constructed by the superposition of the three geodesic potentials generated from three ...

Jribi, Majdi; Ghorbel, Faouzi
Západočeská univerzita v Plzni, 2014

Supervised Force Directed Algorithm for the Generation of Flow Maps
Debiasi, Alberto; Simões, Bruno; De Amicis, Raffaele
2014 - anglický Cartographic flow maps are graphical representations for portraying the movement of objects, such as people, goods or traffic network, from one location to another. On the one hand, flow maps can reduce visual clutter by merging single representations of movement. On the other hand, flow maps are also fast to produce and simple to understand. In this paper, we present a new method for the automatic generation of flow maps. Our method is based on a theoretically grounded physical system to describe the motion and forces of attraction and repulsion between data points. Additionally, support for an optional supervision of the graph layout is also available. Finally, the cost of our algorithm is evaluated and a comparison with existing implementations is provided. Results have shown a good balance between computational complexity and the visual quality of the generated maps. Klíčová slova: mapy toku; kartografie; geovizualizace; grafická interakce; flow maps; cartography; geovisualization; graphic interaction Plné texty jsou dostupné v digitálním repozitáři ZČU. Supervised Force Directed Algorithm for the Generation of Flow Maps

Cartographic flow maps are graphical representations for portraying the movement of objects, such as people, goods or traffic network, from one location to another. On the one hand, flow maps can ...

Debiasi, Alberto; Simões, Bruno; De Amicis, Raffaele
Západočeská univerzita v Plzni, 2014

Review and Comparative Study of Ray Traversal Algorithms on a Modern GPU Architecture
dos Santos, Artur Lira; Teichrieb, Veronica; Lindoso, Jorge
2014 - anglický In this paper we present a chronological review of five distinct data structures commonly found in literature and ray tracing systems: Bounding Volume Hierarchies (BVH), Octrees, Uniform Grids, KD-Trees, and Bounding Interval Hierarchies (BIH). This review is then followed by an extensive comparative study of six different ray traversal algorithms implemented on a modern Kepler CUDA GPU architecture, to point out pros and cons regarding performance and memory consumption of such structures. We show that a GPU KD-Tree ray traversal based on ropes achieved the best performance results. It surpasses the BVH, often used as primary structure on state-of-the-art ray tracers. Compared to BVHs, a carefully well implemented ropes-based KD-Tree is from 13 to 71% faster. However, it may consume up to 9x more memory than other structures. This disadvantage can be a limiting factor on memory limited architectures. Klíčová slova: sledování paprsku; algoritmy traversace paprsku; reprezentace scény pomocí hierarchie obálek; octree; uniformní mřížky; kd strom; ray tracing; ray traversal algorithms; bounding volume hierarchy; octree; uniform grids; kd tree; bounding interval hierarchy Plné texty jsou dostupné v digitálním repozitáři ZČU. Review and Comparative Study of Ray Traversal Algorithms on a Modern GPU Architecture

In this paper we present a chronological review of five distinct data structures commonly found in literature and ray tracing systems: Bounding Volume Hierarchies (BVH), Octrees, Uniform Grids, ...

dos Santos, Artur Lira; Teichrieb, Veronica; Lindoso, Jorge
Západočeská univerzita v Plzni, 2014

A new way of Rich Image Representation (VectorPixels)
Simons, Alain; Prakash, Edmond; Wood, James
2014 - anglický For decades the same technologies has been used for generating images on computer systems. On the one hand you have bitmap and on the other hand vector technology. Bitmap or pixel technology is mostly used for the representation of rich colour images. The other available imaging technology, vectors, is mainly used to present logos and drawings without photo realistic details. But both techniques have their disadvantages and advantages. In recent years a lot of research has been done to combine the advantages of both techniques in a comprehensive solution. Much research focused on giving a vector illustration a realistic picture look. There was no development from scratch and that is exactly what this paper wants to propose, an algorithm to invent the pixel again. By always applying new developments on existing technologies generating images became a mix of various techniques and a rather complex matter. With the use of VectorPixels (VP) the concept of a pixel will be redefined. In contrast with a pixel (Picture Element) a VectorPixel will be defined by a mathematical description and be resolution independent. Klíčová slova: pixely; vektorové pixely; popis obrazu; pixels; vectorpixels; image description Plné texty jsou dostupné v digitálním repozitáři ZČU. A new way of Rich Image Representation (VectorPixels)

For decades the same technologies has been used for generating images on computer systems. On the one hand you have bitmap and on the other hand vector technology. Bitmap or pixel technology is mostly ...

Simons, Alain; Prakash, Edmond; Wood, James
Západočeská univerzita v Plzni, 2014

Connect-S: A Physical Visualization Through Tangible Interaction
Giang, Ken; Funk, Mathias
2014 - anglický In our current society, open data streams are more and more available through the Internet. This data can have an increasing impact on everyday life. Its full potential can, however, only reached through better integration and new interfaces. The goal of this project is to explore the possibilities of repurposing public information in a developing area of a large city in the Netherlands. Can we create a tangible interaction with use of physical visualization of these data streams? A series of prototypes have been made to develop a physical visualization through the method of research through design. Users were involved in expert panels and interviews to fine-tune and create a final prototype, Connect-S. The concept shows the opportunities of using physical visualization in connection with physical interaction for browsing and navigation. Klíčová slova: fyzická vizualizace; taktilní interakce; interaktivní systémy; physical visualization; tangible interaction; interactive systems Plné texty jsou dostupné v digitálním repozitáři ZČU. Connect-S: A Physical Visualization Through Tangible Interaction

In our current society, open data streams are more and more available through the Internet. This data can have an increasing impact on everyday life. Its full potential can, however, only reached ...

Giang, Ken; Funk, Mathias
Západočeská univerzita v Plzni, 2014

Adaptive Projection Displays: a low cost system for public interactivity
Dundas, Jenna; Wagner, Michael
2014 - anglický Interactive digital public displays that track viewer’s position are currently inaccessible to the average consumer. Many tracking systems available on the market are prohibitively expensive and are out of scope for small business owners to purchase. A system can be devised by researching and testing various consumer level tracking technologies in a low cost and accessible manner. Microsoft’s Kinect in tandem with Unity3D offers a system that is straightforward to use and allows for ease of implementation. The resulting technique can be quickly carried out to create an interactive digital public display. Klíčová slova: Microsoft Kinect; projekce; veřejné displeje; interaktivita; počítačová grafika; Microsoft Kinect; projection; public displays; interactivity; computer graphics Plné texty jsou dostupné v digitálním repozitáři ZČU. Adaptive Projection Displays: a low cost system for public interactivity

Interactive digital public displays that track viewer’s position are currently inaccessible to the average consumer. Many tracking systems available on the market are prohibitively expensive and are ...

Dundas, Jenna; Wagner, Michael
Západočeská univerzita v Plzni, 2014

Lane Marking Detection in Various Lighting Conditions using Robust Feature Extraction
Jang, Ho-Jin; Baek, Seung-Hae; Park, Soon-Yong
2014 - anglický Robustly extracting the features of lane markings under different lighting and weather conditions such as shadows, glows, sunset and night is the a key technology of the lane departure warning system (LDWS). In this paper, we propose a robust lane marking feature extraction method. By useing the characteristics of the lane marking to detect candidate areas. The final lane marking features are extracted by first finding the center points of the lane marking in the candidate area then these center point pixels are labeled according to the intensity similarity along the direction of the vanishing point. The performance of the proposed method is evaluated by experiment at results using real world lane data. Klíčová slova: extrakce znaků; detekce obrazu; značení cest; zpracování obrazu; počítačové vidění; feature extraction; image detection; lane marking; image processing; computer vision Plné texty jsou dostupné v digitálním repozitáři ZČU. Lane Marking Detection in Various Lighting Conditions using Robust Feature Extraction

Robustly extracting the features of lane markings under different lighting and weather conditions such as shadows, glows, sunset and night is the a key technology of the lane departure warning system ...

Jang, Ho-Jin; Baek, Seung-Hae; Park, Soon-Yong
Západočeská univerzita v Plzni, 2014

Survey on Automated LEGO Assembly Construction
Kim, Jae Woo; Kang, Kyung Kyu; Lee, Ji Hyoung
2014 - anglický LEGO has been very popular toy in the world because it is attractive and fun to play with and stimulates one's creativity by providing means to conveniently assemble a variety of interesting shapes using the limited types of given bricks. However, it is hard for the beginners to design and assemble complex models they desire to make without instructions. Building a LEGO assembly manually usually requires a significant amount of trial-anderror. LEGO company therefore presented the LEGO construction problem in 1998 and in 2001. The problem statement is "Given any 3D body, how can it be built from LEGO bricks?" In this paper we will investigate the current research efforts to address the LEGO construction problem. We will review the problem definition, formulation, and a variety of approaches to solve the problem. We will discuss the data representations for input 3D polygonal models and the LEGO assembly structures, cost functions that will guide the search for the optimal solution, and various solution methods. Klíčová slova: 3D modely; polygonální mřížky; evoluční algoritmy; LEGO konstrukce; 3D models; polygonal meshes; evolutionary algorithms; LEGO constructions Plné texty jsou dostupné v digitálním repozitáři ZČU. Survey on Automated LEGO Assembly Construction

LEGO has been very popular toy in the world because it is attractive and fun to play with and stimulates one's creativity by providing means to conveniently assemble a variety of interesting shapes ...

Kim, Jae Woo; Kang, Kyung Kyu; Lee, Ji Hyoung
Západočeská univerzita v Plzni, 2014

Energy utilization of biomass in the region of east Slovakia
German-Sobek, Martin; Pavlík, Marek; Bucko, Samuel
2014 - anglický This paper deals about energy utilization of biomass. Biomass is an important renewable energy source and has potential to cover part of the electricity production. The aim of the paper is analysis of wood biomass for energy utilization in region of east Slovakia. Klíčová slova: biomasa; energie; východní Slovensko; biomass; energy; east Slovakia Plné texty jsou dostupné v digitálním repozitáři ZČU. Energy utilization of biomass in the region of east Slovakia

This paper deals about energy utilization of biomass. Biomass is an important renewable energy source and has potential to cover part of the electricity production. The aim of the paper is analysis ...

German-Sobek, Martin; Pavlík, Marek; Bucko, Samuel
Západočeská univerzita v Plzni, 2014

Assessment of biomass fuel resource potential and energetic utilization in Poland (the local market in Lower Silesia)
Hardy, Tomasz
2014 - anglický Klíčová slova: biomasa; energetické využití; Dolní Slezsko; biomass; energetic utilization; Lower Silesia Plné texty jsou dostupné v digitálním repozitáři ZČU. Assessment of biomass fuel resource potential and energetic utilization in Poland (the local market in Lower Silesia)

Hardy, Tomasz
Západočeská univerzita v Plzni, 2014