Straightening out planar poly-line drawings

We show that any $y$-monotone poly-line drawing can be straightened out while maintaining $y$-coordinates and height. The width may increase much, but we also show that on some graphs exponential width is required if we do not want to increase the height. Likewise $y$-monotonicity is required: there are poly-line drawings (not $y$-monotone) that cannot be straightened out while maintaining the height. We give some applications of our result.Comment: The main result turns out to be known (Pach & Toth, J. Graph Theory 2004, http://onlinelibrary.wiley.com/doi/10.1002/jgt.10168/pdf

Omniview motionless camera orientation system

An apparatus and method is provided for converting digital images for use in an imaging system. The apparatus includes a data memory which stores digital data representing an image having a circular or spherical field of view such as an image captured by a fish-eye lens, a control input for receiving a signal for selecting a portion of the image, and a converter responsive to the control input for converting digital data corresponding to the selected portion into digital data representing a planar image for subsequent display. Various methods include the steps of storing digital data representing an image having a circular or spherical field of view, selecting a portion of the image, and converting the stored digital data corresponding to the selected portion into digital data representing a planar image for subsequent display. In various embodiments, the data converter and data conversion step may use an orthogonal set of transformation algorithms

Chemical sensor system

A chemical sensing apparatus and method for the detection of sub parts-per-trillion concentrations of molecules in a sample by optimizing electron utilization in the formation of negative ions is provided. A variety of media may be sampled including air, seawater, dry sediment, or undersea sediment. An electrostatic mirror is used to reduce the kinetic energy of an electron beam to zero or near-zero kinetic energy

An Investigation of Avian Wing Tip Vortex Generation Using a Biomimetic Approach

An experimental study has been conducted to develop a process allowing the creation of biologically accurate aerodynamic test models mimicking the slotted primary feather geometry of the Brown Pelican (Pelecanus occidentalis). Preserved examples of both a full Brown Pelican wing and a single primary feather were 3D scanned and digitally reconstructed using a combination of MATLAB and CAD software. The final model was then 3D printed as a collection of smaller components using a LulzBot TAZ 6 printer and Taulman3D T-Glase PET filament. After using various surface finishing techniques to improve the finish of all 3D printed parts, an assembly was designed to mount the model in the low speed wind tunnel at the California Polytechnic State University. Prior to aerodynamic testing, airfoil sections of the pelican wing were generated in CAD and several common airfoil measurements and characteristics were investigated. At a flow velocity of 5 m/s (Re ~1.21 x 105), wind tunnel smoke and laser visualization testing highlighted the vortex generation of multiple primary feathers, as well as large-scale flow deviations in the vicinity of the feathers. A total pressure rake and total pressure probe were used to create detailed plots of the ratio of the local velocity to free-stream velocity (Vx/Vx∞) at two planes downstream of the model, which revealed vortex positioning consistent with that predicted by smoke visualization testing and provided a metric by which to evaluate the relative strength of each vortex. The model creation process and wind tunnel testing results outlined here provide a strong foundation for future investigations into the potential aerodynamic benefits provided by the slotted primary feather geometry employed by the Brown Pelican and other large gliding avian species

Pressing Forward: A Technical Study of the Mancos Times-Tribune Building With Recommendations for Conservation

The Mancos Times-Tribune Building is located at 135 West Grand Avenue in downtown Mancos, a small town of about 1300 in the Four Corners Regions of southwest Colorado. Built in 1911, it has served as the offices for the local newspaper, The Mancos-Times Tribune Building until the early 2000s. The building is unique for only serving a single function and owner throughout its over 100 year history. It is also in a remarkable state of preservation, making it an excellent case for studying the development of late 19th and early 20th century construction technologies. Through, the study of period literature, materials analysis, and review of conservation techniques for each material, a well-informed conservation program was developed to restore the building for future use by a town with a growing interest in preserving its heritage