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Random-walk and diffusion models for two-choice comparison of paired successive or simultaneous stimuli focus on response time (RT), modeled as the time needed to reach one or the other barrier, and its relation to the response probabilities. Logit P1 = ln[P1/(1-P1)], where P1 is the probability of responding ”first greater,” can be seen as a measure of subjective stimulus difference, d. Signed re

The general aim of this thesis was to study how memorial places and objects serve as links and meeting points between the bereaved and their conceptions and memories of the departed. This has been examined in several different ways, from various viewpoints, and placed in different contexts and periods in time. The general result is that there are several and complementary ways through which materi

We present a hierarchical traversal algorithm for stochastic rasterization of motion blur, which efficiently reduces the number of inside tests needed to resolve spatio-temporal visibility. Our method is based on novel tile against moving primitive tests that also provide temporal bounds for the overlap. The algorithm works entirely in homogeneous coordinates, supports MSAA, facilitates efficient

This paper assumes the availability of a very fast higher-dimensional rasterizer in future graphics processors. Working in up to five dimensions, i.e., adding time and lens parameters, it is well-known that this can be used to render scenes with both motion blur and depth of field. Our hypothesis is that such a rasterizer can also be used as a flexible tool for other, less conventional, usage area

Many combinatorial optimization problems lend themselves to be modeled as distributed constraint optimization problems (DisCOP). Problems such as job shop scheduling have an intuitive matching between agents and machines. In distributed constraint problems, agents control variables and are connected via constraints. We have equipped these agents with a full constraint solver. This makes it possibl

Embedded DSP computing is currently shifting towards manycore architectures in order to cope with the ever growing computational demands. Actor based dataflow languages are being considered as a programming model. In this paper we present a code generator for CAL, one such dataflow language. We propose to use a compilation tool with two intermediate representations. We start from a machine model o

As custom architectures become more and more common for DSP applications, instruction selection and scheduling for such applications and architectures become important topics. In this paper, we explore the effects of defining the problem of finding an optimal instruction selection and scheduling as a constraint satisfaction problem (CSP). We incorporate methods based on sub-graph isomorphism and g

Traditional efforts in standardizing video coding used to involve a lengthy process that resulted in large monolithic standards and reference codes. This approach has become increasingly ill-suited to the dynamics and the fast changing needs of the video coding community. Most importantly, there used to be no principled approach to leveraging the significant commonalities between the different cod

A major challenge when designing general purpose graphics hardware is to allow efficient access to texture data. Although different rendering paradigms vary with respect to their data access patterns, there is no flexibility when it comes to data caching provided by the graphics architecture. In this paper we focus on volume ray-casting, and show the benefits of algorithm-aware data caching. Our M

Objective This study provides the summary of current knowledge about migrant work in agriculture available from journal articles, books, reports and other relevant academic publications, focusing on political, economic, legal, social and medical aspects of migrant work in agriculture. Methods A systematic search was carried out on the LibHub and Google Scholar databases in order to compile the e

This paper addresses design space exploration for streaming applications (such as MPEG) running on multi-processor platforms with guaranteed service interconnects. In particular, we solve mapping, path selection and router configuration problems. Given the complexity of these problems, state of the art approaches in this area largely rely on greedy heuristics, which do not guarantee optimality. Ou

The trade-off between throughput and memory constraints is a common design problem in embedded systems, and especially for streaming applications, where the memory in question usually occurs in the form of buffers for streams of data. This paper presents a methodology, based on the post-processing of dataflow execution traces, that enables designers to make principled choices in the design space f

This paper presents a new method for representing Light Propagation Volumes using an octree data structure, and for allowing light from regular point light sources to be injected into them. The resulting technique uses full octrees with the help of a separate data structure for representing the octree structure. The octree structure enables light propagation to be performed at a lower resolution t

Abstract in UndeterminedVideo coding technology in the last 20 yearshas evolved producing a variety of different and com-plex algorithms and coding standards. So far the speci-fication of such standards, and of the algorithms thatbuild them, has been done case by case providingmonolithic textual and reference software specifica-tions in different forms and programming languages.However, very littl

Heterogeneous parallel systems are becoming mainstream computing platforms nowadays. One of the main challenges the development community is currently facing is how to fully exploit the available computational power when porting existing programs or developing new ones with available techniques. In this direction, several design space exploration methods have been presented and extensively adopted

Homogeneous charge compression ignition (HCCI) holds promise for reduced emissions and increased efficiency compared to conventional internal combustion engines. As HCCI lacks direct actuation over the combustion phasing, much work has been devoted to designing controllers capable of set-point tracking and disturbance rejection. This paper presents results on model predictive control (MPC) of the

The oxidation of biogenic volatile organic compounds (BVOCs) gives a range of products, from semi-volatile to extremely low-volatility compounds. To treat the interaction of these secondary organic vapours with the particle phase, global aerosol microphysics models generally use either a thermodynamic partitioning approach (assuming instant equilibrium between semi-volatile oxidation products and

When rendering effects such as motion blur and defocus blur, shading can become very expensive if done in a naive way, i.e. shading each visibility sample. To improve performance, previous work often decouple shading from visibility sampling using shader caching algorithms. We present a novel technique for reusing shading in a stochastic rasterizer. Shading is computed hierarchically and sparsely