Analysis of Scalable Algorithms for Dynamic Load Balancing and Mapping with Application to Photo-realistic Rendering

This thesis presents and analyzes scalable algorithms for dynamic load balancing and mapping in distributed computer systems. The algorithms are distributed and concurrent, have no central thread of control, and require no centralized communication. They are derived using spectral properties of graphs: graphs of physical network links among computers in the load balancing problem, and graphs of logical communication channels among processes in the mapping problem. A distinguishing characteristic of these algorithms is that they are scalable: the expected cost of execution does not increase with problem scale. This is proven in a scalability theorem which shows that, for several simple disturbance models, the rate of convergence to a solution is independent of scale. This property is extended through simulated examples and informal argument to general and random disturbances. A worst case disturbance is presented and shown to occur with vanishing probability as the problem scale increases. To verify these conclusions the load balancing algorithm is deployed in support of a photo-realistic rendering application on a parallel computer system based on Monte Carlo path tracing. The performance and scaling of this application, and of the dynamic load balancing algorithm, are measured on different numbers of computers. The results are consistent with the predictions of scalability, and the cost of load balancing is seen to be non-increasing for increasing numbers of computers. The quality of load balancing is evaluated and compared with the quality of solutions produced by competing approaches for up to 1,024 computers. This comparison shows that the algorithm presented here is as good as or better than the most popular competing approaches for this application. The thesis then presents the dynamic mapping algorithm, with simulations of a model problem, and suggests that the pair of algorithms presented here may be an ideal complement to more expensive algorithms such as the well-known recursive spectral bisection

Scalable Load Balancing by Diffusion

[No abstract available

Bayesian Train Localization with Particle Filter, Loosely Coupled GNSS, IMU, and a Track Map

Train localization is safety-critical and therefore the approach requires a continuous availability and a track-selective accuracy. A probabilistic approach is followed up in order to cope with multiple sensors, measurement errors, imprecise information, and hidden variables as the topological position within the track network. The nonlinear estimation of the train localization posterior is addressed with a novel Rao-Blackwellized particle filter (RBPF) approach. There, embedded Kalman filters estimate certain linear state variables while the particle distribution can cope with the nonlinear cases of parallel tracks and switch scenarios. The train localization algorithmis further based on a trackmap andmeasurements froma GlobalNavigation Satellite System(GNSS) receiver and an inertial measurement unit (IMU). The GNSS integration is loosely coupled and the IMU integration is achieved without the common strapdown approach and suitable for low-cost IMUs.The implementation is evaluated with realmeasurements from a regional train at regular passenger service over 230 km of tracks with 107 split switches and parallel track scenarios of 58.5 km.The approach is analyzed with labeled data by means of ground truth of the traveled switch way. Track selectivity results reach 99.3% over parallel track scenarios and 97.2% of correctly resolved switch ways

Cultural Breakthroughs

Recognizing that the production metaphor best fits the stages of normal culture production, Heirich shows how scientific, artistic, and religious modes of inquiry build upon societal roots to produce cultural breakthroughs of revolutionary character.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66669/2/10.1177_000276427601900602.pd

Change of Heart: A Test of Some Widely Held Theories about Religious Conversion

http://deepblue.lib.umich.edu/bitstream/2027.42/50862/1/82.pd

Scalable Interactive Volume Rendering Using Off-the-shelf Components

This paper describes an application of a second generation implementation of the Sepia architecture (Sepia-2) to interactive volu-metric visualization of large rectilinear scalar fields. By employingpipelined associative blending operators in a sort-last configuration a demonstration system with 8 rendering computers sustains 24 to 28 frames per second while interactively rendering large data volumes (1024x256x256 voxels, and 512x512x512 voxels). We believe interactive performance at these frame rates and data sizes is unprecedented. We also believe these results can be extended to other types of structured and unstructured grids and a variety of GL rendering techniques including surface rendering and shadow map-ping. We show how to extend our single-stage crossbar demonstration system to multi-stage networks in order to support much larger data sizes and higher image resolutions. This requires solving a dynamic mapping problem for a class of blending operators that includes Porter-Duff compositing operators

From War to War featuring Feminine Torture

From War to War featuring Feminine Torture is an investigation of the trialectics of Transience, Liminal Space and Nomadic Movement. These ideas are researched through a durational performance that was transcribed into a novella titled From War to War, and a video work that responds to the novella's breakdown through ruptures and stutters in endurance

A inserção de mídias impressa e informática no curso de formação de docentes

Orientador :Monografia (especialização) - Universidade Federal do Paraná, Setor de ..., Curso de Especialização em ...Inclui referência

Worksite Follow-Up and Engagement Strategies for Initiating Health Risk Behavior Changes

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66663/2/10.1177_109019819001700409.pd