Roger Bacon as a Scientist.

Reprinted from The Open court, August, 1914.Mode of access: Internet

Appearance Preserving Rendering of Out-of-Core Polygon and NURBS Models

In Computer Aided Design (CAD) trimmed NURBS surfaces are widely used due to their flexibility. For rendering and simulation however, piecewise linear representations of these objects are required. A relatively new field in CAD is the analysis of long-term strain tests. After such a test the object is scanned with a 3d laser scanner for further processing on a PC. In all these areas of CAD the number of primitives as well as their complexity has grown constantly in the recent years. This growth is exceeding the increase of processor speed and memory size by far and posing the need for fast out-of-core algorithms. This thesis describes a processing pipeline from the input data in the form of triangular or trimmed NURBS models until the interactive rendering of these models at high visual quality. After discussing the motivation for this work and introducing basic concepts on complex polygon and NURBS models, the second part of this thesis starts with a review of existing simplification and tessellation algorithms. Additionally, an improved stitching algorithm to generate a consistent model after tessellation of a trimmed NURBS model is presented. Since surfaces need to be modified interactively during the design phase, a novel trimmed NURBS rendering algorithm is presented. This algorithm removes the bottleneck of generating and transmitting a new tessellation to the graphics card after each modification of a surface by evaluating and trimming the surface on the GPU. To achieve high visual quality, the appearance of a surface can be preserved using texture mapping. Therefore, a texture mapping algorithm for trimmed NURBS surfaces is presented. To reduce the memory requirements for the textures, the algorithm is modified to generate compressed normal maps to preserve the shading of the original surface. Since texturing is only possible, when a parametric mapping of the surface - requiring additional memory - is available, a new simplification and tessellation error measure is introduced that preserves the appearance of the original surface by controlling the deviation of normal vectors. The preservation of normals and possibly other surface attributes allows interactive visualization for quality control applications (e.g. isophotes and reflection lines). In the last part out-of-core techniques for processing and rendering of gigabyte-sized polygonal and trimmed NURBS models are presented. Then the modifications necessary to support streaming of simplified geometry from a central server are discussed and finally and LOD selection algorithm to support interactive rendering of hard and soft shadows is described

THE UNIVERSITY OF MICHIGAN PHILIPPINE EXPEDITION

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75181/1/aa.1927.29.1.02a00040.pd

Some Peculiarities in the Elastic Properties of Certain Substances

All solids deviate more or less from the theoretical perfectly elastic body and though many experiments have been undertaken in order to explain these deviations, we can hardly claim that any of the numerous theories proposed by the different investigators has yet cleared up the intricate relations involved

Electrical Standards

As soon as any commodity becomes of commercial value a system of practical units has to be established for its measurement. In the case of electrical energy we have fortunately been saved from the natural development of a system of units, a development which has, for example, given us our remarkably complex, incongruous, and unscientific collection of weights and measures. While by no means perfect the electrical units have at least the advantage of being consistent, and being worked out by scientists they have naturally been based upon the metric system

The Books of Ezra and Nehemiah

The books of Ezra and Nehemiah : critical edition of the Hebrew text printed in colors exhibiting the composite structure of the book / with notes by Hermann Guthe ; English translation of the notes by B.W. Bacon and D.B. Macdonald ; with additions by L.W. Batten.https://scholar.csl.edu/ebooks/1013/thumbnail.jp

Intersecting Global and Local: Spatial Analysis of Ethnicities of Asian Businesses in the Minneapolis-Saint Paul Metro Area

The changing nature of immigration to the United States and changes in the morphology of American cities challenge traditional theories of ethnic entrepreneurship as a means of success in assimilating into American society. This study, based on data of over 800 businesses in the Minneapolis-Saint Paul area, finds that specific Asian ethnic groups demonstrate distinctive patterns, which often do not conform to traditional theories of ethnic entrepreneurship. Instead, other concepts, such as heterolocalism and transnationalism, add to the discussion concerning a new role for modern ethnic entrepreneurs. This new role must examine ethnic businesses as localities of transnationalism in a global context

Electrical conductivity in granular media and Branly's coherer: A simple experiment

accepted for publication in American Journal of Physics (to be published between February 2005 and June 2005)We show how a simple laboratory experiment can illustrate certain electrical transport properties of metallic granular media. At a low critical imposed voltage, a transition from an insulating to a conductive state is observed. This transition comes from an electro-thermal coupling in the vicinity of the microcontacts between grains where microwelding occurs. Our apparatus allows us to obtain an implicit determination of the microcontact temperature, which is analogous to the use of a resistive thermometer. The experiment also illustrates an old problem, the explanation of Branly's coherer effect - a radio wave detector used for the first wireless radio transmission, and based on the sensitivity of the metal fillings conductivity to an electromagnetic wave