Set Of Tiles Research Articles

A tile service-driven architecture for online climate analysis with an application to estimation of ocean carbon flux

The deteriorating environmental system and increasing number of time-varying datasets have generated a significant demand for new techniques to support online high-efficiency climate analysis. In response to this demand, this paper introduces an innovative multilayer architecture driven by a tile service in a virtual globe environment. This architecture is supported by the open-source and highly efficient osgEarth virtual globe. In addition, we develop a gSoap-based tile service to address the challenges of visualizing and analysing massive data under hardware restrictions conditions. The service contains a lossless pyramid tile set that can automatically provide tiles with proper accuracy according to the demands of users under different conditions. Furthermore, we add a hybrid database file system to the service for high availability. This service is then applied for estimation of ocean carbon flux. And a proof-of-concept prototype, SatCO2, has been developed to demonstrate the feasibility and performance of the proposed architecture.

Design and Implementation of Cache Memory with Dual Unit Tile/Line Accessibility

In recent years, the increasing disparity between the data access speed of cache and processing speeds of processors has caused a major bottleneck in achieving high-performance 2-dimensional (2D) data processing, such as that in scientific computing and image processing. To solve this problem, this paper proposes new dual unit tile/line access cache memory based on a hierarchical hybrid Z-ordering data layout and multibank cache organization supporting skewed storage schemes. The proposed layout improves 2D data locality and reduces L1 cache misses and Translation Lookaside Buffer (TLB) misses efficiently and it is transformed from conventional raster layout by a simple hardware-based address translation unit. In addition, we proposed an aligned tile set replacement algorithm (ATSRA) for reduction of the hardware overhead in the tag memory of the proposed cache. Simulation results using Matrix Multiplication (MM) illustrated that the proposed cache with parallel unit tile/line accessibility can reduce both the L1 cache and TLB misses considerably as compared with conventional raster layout and Z-Morton order layout. The number of parallel load instructions for parallel unit tile/line access was reduced to only about one-fourth of the conventional load instruction. The execution time for parallel load instruction was reduced to about one-third of that required for conventional load instruction. By using 40 nm Complementary Metal-Oxide-Semiconductor (CMOS) technology, we combined the proposed cache with a SIMD-based data path and designed a 5 × 5 mm2 Large-Scale Integration (LSI) chip. The entire hardware overhead of the proposed ATSRA-cache was reduced to only 105% of that required for a conventional cache by using the ATSRA method.

Graph-Based Construction of 3D Korean Giwa House Models

This paper proposes a graph-based algorithm for constructing 3D Korean traditional houses automatically using a computer graphics technique. In particular, we target designing the most popular traditional house type, a giwa house, whose roof is covered with a set of Korean traditional roof tiles called giwa. In our approach, we divided the whole design processes into two different parts. At a high level, we propose a special data structure called ‘modeling graphs’. A modeling graph consists of a set of nodes and edges. A node represents a particular component of the house and an edge represents the connection between two components with all associated parameters, including an offset vector between components. Users can easily add/ delete nodes and make them connect by an edge through a few mouse clicks. Once a modeling graph is built, then it is interpreted and rendered on a component-by-component basis by traversing nodes in a procedural way. At a low level, we came up with all the required parameters for constructing the components. Among all the components, the most beautiful but complicated part is the gently curved roof structures. In order to represent the sophisticated roof style, we introduce a spline curve-based modeling technique that is able to create curvy silhouettes of three different roof styles. In this process, rather than just applying a simple texture image onto the roof, which is widely used in commercial software, we actually laid out 3D giwa tiles on the roof seamlessly, which generated more realistic looks. Through many experiments, we verified that the proposed algorithm can model and render the giwa house at a real time rate.

Visual Attention-Aware Omnidirectional Video Streaming Using Optimal Tiles for Virtual Reality

Owing to its interactive look around nature and very large resolution requirement, providing immersive omnidirectional video (ODV) streaming experiences in virtual reality applications demands cost-effective solutions to meet both the content delivery network and device constraints. In this paper, we introduce an adaptive ODV streaming pipeline that optimizes dynamic adaptive streaming over HTTP representations of ODV content considering their visual attention (VA) maps. The main contribution of this paper is the use of VA maps: 1) to compute a novel objective quality metric that captures the fact that not all of the ODV is actually watched by users: the VA spherical weighted-based objective quality measurement; 2) to define optimal tile representations of the ODV frames, namely, tiling schemes, which are composed of variable-sized and non-overlapping tiles; and 3) to efficiently distribute a given bitrate budget among the set of tiles within a tiling scheme for an ODV. We evaluate the proposed system performance with varying bandwidth conditions and the tracked head orientations from user experiments. Results show that the proposed system significantly outperforms the existing non-tiled and tile-based streaming solutions.

Diverse and robust molecular algorithms using reprogrammable DNA self-assembly.

Molecular biology provides an inspiring proof-of-principle that chemical systems can store and process information to direct molecular activities such as the fabrication of complex structures from molecular components. To develop information-based chemistry as a technology for programming matter to function in ways not seen in biological systems, it is necessary to understand how molecular interactions can encode and execute algorithms. The self-assembly of relatively simple units into complex products1 is particularly well suited for such investigations. Theory that combines mathematical tiling and statistical-mechanical models of molecular crystallization has shown that algorithmic behaviour can be embedded within molecular self-assembly processes2,3, and this has been experimentally demonstrated using DNA nanotechnology4 with up to 22 tile types5-11. However, many information technologies exhibit a complexity threshold-such as the minimum transistor count needed for a general-purpose computer-beyond which the power of a reprogrammable system increases qualitatively, and it has been unclear whether the biophysics of DNA self-assembly allows that threshold to be exceeded. Here we report the design and experimental validation of a DNA tile set that contains 355 single-stranded tiles and can, through simple tile selection, be reprogrammed to implement a wide variety of 6-bit algorithms. We use this set to construct 21 circuits that execute algorithms including copying, sorting, recognizing palindromes and multiples of 3, random walking, obtaining an unbiased choice from a biased random source, electing a leader, simulating cellular automata, generating deterministic and randomized patterns, and counting to 63, with an overall per-tile error rate of less than 1 in 3,000. These findings suggest that molecular self-assembly could be a reliable algorithmic component within programmable chemical systems. The development of molecular machines that are reprogrammable-at a high level of abstraction and thus without requiring knowledge of the underlying physics-will establish a creative space in which molecular programmers can flourish.

Multiphase mineral identification and quantification by laser-induced breakdown spectroscopy

Quantitative mineral analysis (QMA) performed using energy-dispersive x-ray spectrometry and scanning electron microscopes (EDS-SEM) provide reliable information on the mineral abundance and texture of prepared rocks. This information helps in the optimization of the mining and milling processes, and to define the value of a deposit. Real-time analysis of coarse rock streams would greatly enhance the decision-making processes driving the mining operation efficiency; however electron-microscope-based instruments are not yet adaptable for in-field measurements. Laser-induced breakdown spectroscopy (LIBS) has been used for elemental analysis in many environments but has not been employed for true mineral quantification and identification. This work presents a new method for mineral identification and quantification using LIBS, which could be scalable to perform automated mineralogy measurement in coarse rock streams. A set of rock tiles from mining operations in Australia had QMA performed using an EDS-SEM instrument and the resulting data were used to guide and validate the results obtained by LIBS. The use of a multivariate curve resolution – alternating least square (MCR-ALS) method applied to the LIBS data allowed the identification, quantification and imaging of minerals on rock tiles, even in the presence of mixed mineral phases within the laser spot area. Mineral abundance and imaging are obtained with success for the mineral phases selected in the present work, which includes bornite, chalcopyrite, pyrite, molybdenite, quartz, chlorite, K-feldspar, albite, fluorite and calcite. The method presented a mineral quantification root mean square error below 10% for the main minerals. In addition, mineral quantification by point-counting using single laser shots per LIBS measurement is demonstrated, achieving absolute errors below 3.5% for major minerals and below 1% for minor minerals.

IMAGE SYNTHESIS OF METAL FOAM MICRO-STRUCTURE WITH THE USE OF WANG TILES

<p>In this paper we present our recent work focused on the analysis of the abilities of Wang Tiles method and Automatic tile design method to synthesize the micro-structure of cellular materials, especially particular type of metal foam.</p><p>Wang Tiles method stores and compress the micro-structure in a set of Wang Tiles and by the means of stochastic tiling algorithms the planar domain is reconstructed. The used tiles are created by the Automatic tile design method from respective number of small specimens extracted from the original micro-structure image. As an additional step the central areas of automatically designed tiles are patched to suppress the influence of repeating tile edges (and relevant tile quarters) on inducing artifacts. In the presented analysis the performance of raw and patched tiles of different sizes in conjunction of various tile sets is investigated.</p>

Multi-Criteria Decision Making for Efficient Tiling Path Planning in a Tetris-Inspired Self-Reconfigurable Cleaning Robot

In this study, we aim to optimize and improve the efficiency of a Tetris-inspired reconfigurable cleaning robot. Multi-criteria decision making (MCDM) is utilized as a powerful tool to target this aim by introducing the best solution among others in terms of lower energy consumption and greater area coverage. Regarding the Tetris-inspired structure, polyomino tiling theory is utilized to generate tiling path-planning maps which are evaluated via MCDM to seek a solution that can deliver the best balance between the two mentioned key issues; energy and area coverage. In order to obtain a tiling area that better meets the requirements of polyomino tiling theorems, first, the whole area is decomposed into five smaller sub-areas based on furniture layout. Afterward, four tetromino tiling theorems are applied to each sub-area to give the tiling sets that govern the robot navigation strategy in terms of shape-shifting tiles. Then, the area coverage and energy consumption are calculated and eventually, these key values are considered as the decision criteria in a MCDM process to select the best tiling set in each sub-area, and following the aggregation of best tiling path-plannings, the robot navigation is oriented towards efficiency and improved optimality. Also, for each sub-area, a preference order for the tiling sets is put forward. Based on simulation results, the tiling theorem that can best serve all sub-areas turns out to be the same. Moreover, a comparison between a fixed-morphology mechanism with the current approach further advocates the proposed technique.

Fixed-Parameter Extrapolation and Aperiodic Order

For a number of years we have been investigating the geometric and algebraic properties of a family of discrete sets of points in Euclidean space generated by a simple binary operation: pairwise affine combination by a xed parameter, which we call xed-parameter extrapolation. By varying the parameter and the set of initial points, a large variety of point sets emerge. To our surprise, many of these sets display aperiodic order and share properties of so-called \quasicrystals" or \quasilattices." Such sets display some ordered crystal-like properties (e.g., generation by a regular set of local rules, such as a nite set of tiles, and possessing a kind of repetitivity), but are \aperiodic" in the sense that they have no translational symmetry. The most famous of such systems are Penrose's aperiodic tilings of the plane [16]. Mathematically, a widely accepted way of capturing the idea of aperiodic order is via the notion of Meyer sets, which we de ne later. Our goal is to classify the sets generated by xed-parameter extrapolation in terms of a number of these properties, including but not limited to aperiodicity, uniform discreteness, and relative density. We also seek to determine exactly which parameter values lead to which types of sets.

Riesz Wavelets, Tiling and Spectral Sets in LCA Groups

Let G be a locally compact abelian (LCA) group equipped with a Haar measure. A collection of measurable subsets $$\{\Omega _i\}_{i=1}^m$$ in $$\hat{G}$$ is called a Riesz wavelet collection if there are countable subsets $$A\subset \mathcal {A}ut(G)$$ and $$\Lambda _i\subset G$$ such that for $$\hat{\psi }_i:= 1_{\Omega _i}$$ , the family $$\begin{aligned} \mathcal {W}:=\cup _{i=1}^m\{\Delta (a)^{1/2} \psi _i(a(x)-\lambda ): \lambda \in \Lambda _i, a\in A\} \end{aligned}$$ is a Riesz basis for $$L^2(G)$$ . In this paper we show that if $$\Omega _i$$ ’s are Riesz spectral sets and $$\Omega =\cup _i \Omega _i$$ is a multiplicative tiling set for $$\hat{G}$$ , then $$\mathcal {W}$$ is a Riesz basis for $$L^2(G)$$ . The converse also holds if the unit element $$e\in G$$ belongs to all $$\Lambda _i$$ . As a result, if $$\Omega _i$$ ’s multi-tile $$\hat{G}$$ additively by lattice and $$\Omega $$ is a multiplicative tiling, then $$\mathcal {W}$$ is a Riesz basis for $$L^2(G)$$ . When $$m=1$$ , we show that the multiplicative tiling property of $$\Omega $$ is equivalent to the Riesz spectral property of $$\hat{\alpha }(\Omega )$$ , $$\alpha \in A$$ , provided that $$\mathcal {W}$$ is a Riesz basis.

Non-periodic Tiling of Procedural Noise Functions

Procedural noise functions have many applications in computer graphics, ranging from texture synthesis to atmospheric effect simulation or to landscape geometry specification. Noise can either be precomputed and stored into a texture, or evaluated directly at application runtime. This choice offers a tradeoff between image variance, memory consumption and performance. Advanced tiling algorithms can be used to decrease visual repetition. Wang tiles allow a plane to be tiled in a non-periodic way, using a relatively small set of textures. Tiles can be arranged in a single texture map to enable the GPU to use hardware filtering. In this paper, we present modifications to several popular procedural noise functions that directly produce texture maps containing the smallest complete Wang tile set. The findings presented in this paper enable non-periodic tiling of these noise functions and textures based on them, both at runtime and as a preprocessing step. These findings also allow decreasing repetition of noise-based effects in computer-generated images at a small performance cost, while maintaining or even reducing the memory consumption.

A self-similar aperiodic set of 19 Wang tiles

We define a Wang tile set $\mathcal{U}$ of cardinality 19 and show that the set $\Omega_\mathcal{U}$ of all valid Wang tilings $\mathbb{Z}^2\to\mathcal{U}$ is self-similar, aperiodic and is a minimal subshift of $\mathcal{U}^{\mathbb{Z}^2}$. Thus $\mathcal{U}$ is the second smallest self-similar aperiodic Wang tile set known after Ammann's set of 16 Wang tiles. The proof is based on the unique composition property. We prove the existence of an expansive, primitive and recognizable $2$-dimensional morphism $\omega:\Omega_\mathcal{U}\to\Omega_\mathcal{U}$ that is onto up to a shift. The proof of recognizability is done in two steps using at each step the same criteria (the existence of marker tiles) for proving the existence of a recognizable one-dimensional substitution that sends each tile either on a single tile or on a domino of two tiles.

Hierarchical Quad Meshing of 3D Scanned Surfaces

AbstractIn this paper we present a novel method to reconstruct watertight quad meshes on scanned 3D geometry. There exist many different approaches to acquire 3D information from real world objects and sceneries. Resulting point clouds depict scanned surfaces as sparse sets of positional information. A common downside is the lack of normals, connectivity or topological adjacency data which makes it difficult to actually recover a meaningful surface. The concept described in this paper is designed to reconstruct a surface mesh despite all this missing information. Even when facing varying sample density, our algorithm is still guaranteed to produce watertight manifold meshes featuring quad faces only. The topology can be set‐up to follow superimposed regular structures or align naturally to the point cloud's shape. Our proposed approach is based on an initial divide and conquer subsampling procedure: Surface samples are clustered in meaningful neighborhoods as leafs of a kd‐tree. A representative sample of the surface neighborhood is determined for each leaf using a spherical surface approximation. The hierarchical structure of the binary tree is utilized to construct a basic set of loose tiles and to interconnect them. As a final step, missing parts of the now coherent tile structure are filled up with an incremental algorithm for locally optimal gap closure. Disfigured or concave faces in the resulting mesh can be removed with a constrained smoothing operator.

Puzz-Ling: A hands-on model of syntax to popularize linguistics as a science

Modern theoretical linguistics is arguably a science with a well-defined methodology, relatively simple and inexpensive data-collection strategies and clear objectives, yet the study of human language is not widely recognized by the general public as a scientific endeavor. Formal syntax and semantics, for instance, have not been popularized, like physics, chemistry, or other hard sciences, and have very rarely found a space in science museums. In this paper, we discuss some aspects of this problem, focusing on syntax and its potential in education and arguing that the lack of popularization derives from the need for different methods of dissemination. To overcome this problem, we present a completely novel approach to syntax education, based on a physical, hands-on multilingual model, which we have designed and built. The model, called Puzz-Ling, consists of a set of tiles that can be combined only to form grammatical sentences, in three languages (English, German, and Italian). A simple set of rules and symbols and a string–reordering system based on constituent swapping derive the correct word order in all three languages. The model introduces in a simple and entertaining form some key concepts of (generative) syntax (e.g., tree structures, binary branching, and movement) and displays in an intuitive way the structural difference among languages. The system can be turned into a game with the addition of points and turns, resulting in a hands-on, “edutainment” approach to language. The mechanics of the game are briefly described, and various trade-offs encountered in the design phase are discussed.

Tile-based Pattern Design with Topology Control

Patterns with desired aesthetic appearances and physical structures are ubiquitous. However, such patterns are challenging to produce -- manual authoring requires significant expertise and efforts while automatic computation lacks sufficient flexibility and user control. We propose a method that automatically synthesizes vector patterns with visual appearance and topological structures designated by users via input exemplars and output conditions. The input can be an existing vector graphics design or a new one manually drawn by the user through our interactive interface. Our system decomposes the input pattern into constituent components (tiles) and overall arrangement (tiling). The tile sets are general and flexible enough to represent a variety of patterns, and can produce different outputs with user specified conditions such as size, shape, and topological properties for physical manufacturing.

Cracks avoidance with a modified solid tungsten divertor in ASDEX Upgrade

To clarify the suitability of solid tungsten as plasma facing material, a new divertor, DIV-III, entered in operation in ASDEX Upgrade (AUG) in 2014. Since the first experimental campaign, AUG divertor tiles faced crack issues. Trying to identify the reasoning, a new set of tiles was installed in 2016: many precautions were taken to reduce the stresses possibly causing the cracks. The AUG campaign 2017 started in March and the first results were collected during the short summer opening in 2017. This paper reports on the modification of the tile setup, based on Finite Element Modelling, and on the progress achieved in the first operation phase.

Revisiting a Tiling Hierarchy

We revisit Golomb’s tiling hierarchy for finite sets of polyominoes. We consider the case when only translations are allowed for the tiles in a tile set. In this classification, for several levels in Golomb’s hierarchy, more types need to be considered. First, we show that there is no general relationship among the types corresponding to a fixed level for the existence of tilings. Second, we review the relationships among the levels from Golomb’s hierarchy that are still valid in this setup, and third, we give counterexamples for several relationships in Golomb’s hierarchy that fail. As a consequence of the results, we show alternative tiling hierarchies. We also show some unexpected additions to all of the above hierarchies and discuss various implications of tiling capabilities if deficient regions are added to the pool.

An innovative Braille alphabet teaching tool for visually impaired individuals based on advanced tactile embossed 3D graphics

In this paper, tactile tiles for teaching Braille alphabet were created using three different 3D printing techniques. Aim of this work, based on research with visually impaired individuals, is to provide educators with a new and better way of teaching the Braille alphabet with a complete 3D printed set of alphabet tiles. Recent developments in 3D printing technology enable researchers to experiment with new approaches towards the creation of new tools for teaching the Braille alphabet. It is important to examine the Braille lettering standards, capabilities of 3D printers and, in cooperation with experts who work with the visually impaired, discuss the design and functionality of the created tiles. In this research, a set of 3D printed tiles has been created, each divided into three main parts. The first part of the tile shows a basic Braille letter. This is followed by a corresponding embossed model of an object that correlates to the first letter of the word. The third section consists of the entire word corresponding to the embossed model at the bottom of the tile in Braille writing. Tiles are standardized by size and part position for corresponding letters of the alphabet and words describing the embossed model. These tiles are intended to serve as a supplemental educational tool that relies on the sense of touch as a way for the visually impaired individuals to more easily connect their own perception of familiar objects from their surroundings to words and letters. Several iterations of tiles have been printed with multiple 3D printers, with the purpose of determining optimal settings required for producing the best possible product prototype.

Equivalence between Clar covering polynomials of single zigzag chains and tiling polynomials of [formula omitted] rectangles

This paper offers a formal explanation of a rather puzzling and surprising equivalence between the Clar covering polynomials of single zigzag chains and the tiling polynomials of 2×n rectangles for tilings using 1 × 2, 2 × 1 and 2 × 2 tiles. It is demonstrated that the set of Clar covers of single zigzag chains N(n−1) is isomorphic to the set of tilings of a 2×n rectangle. In particular, this isomorphism maps Clar covers of N(n−1) with k aromatic sextets to tilings of a 2×n rectangle using k square 2 × 2 tiles. The proof of this fact is an application of the recently introduced interface theory of Clar covers. The existence of a similar relationship between the Clar covers of more general benzenoid structures and more general tilings of rectangles remains an interesting open problem in chemical graph theory.

A Zonotope and a Product of Two Simplices with Disconnected Flip Graphs

We give an example of a three-dimensional zonotope whose set of tight zonotopal tilings is not connected by flips. Using this, we show that the set of triangulations of Delta ^4 times Delta ^n is not connected by flips for large n. Our proof makes use of a non-explicit probabilistic construction.