UCAR > Communications > Staff Notes > May 1999 Search

May 1999

Patently impressive: Four RAP creations get the nod from Uncle Sam

The RAP staff honored at this year's Inventor Recognition Luncheon: (standing, left to right) Chuck Wade, Frank Hage, Jothiram Vivekanandan, and Roy Rasmussen; (seated) Bill Myers and Larry Cornman. (Photo by Carlye Calvin.)

The Research Applications Program has been keeping the U.S. Patent Office busy. In 1998, all four of the patents granted to NCAR were for inventions based in RAP. Seven of the people behind these patents were honored at the third Inventor Recognition Luncheon on 26 April at the Boulder Cork. The event is sponsored each year by UCAR's Intellectual Property Management Program. Every honoree gets a plaque inscribed with pertinent information from the front page of his or her patent.

RAP's Larry Cornman, who didn't earn a patent this past year, was honored with an Outstanding Achievement Award for his work on the Low-Level Wind Shear Alert System. Larry's four LLWAS-related patents between 1993 and 1994 made him the institution's most prolific patenter, a title he still holds. (Another patent application from Larry, along with Kent Goodrich and Cory Morse, is now in process; it's related to quality control of wind-profiler data.)

UCAR president Rick Anthes joined NCAR director Bob Serafin to present the plaques at the banquet. "I'm always impressed by the combination of science and technology that goes into these inventions," said Rick. Bob noted that "In many respects, a patent is like a publication--it gets a very thorough peer review." He added with a laugh that he'd earned several patents of his own, but they predated the IPMP program, so "I never got a beautiful plaque like this."

Below is a brief description of each 1998 patent. All inventors listed are from RAP unless otherwise noted. •Bob Henson

Winter Precipitation Measuring System

Patent No. 5,744,711, issued 28 April

Inventors: Roy Rasmussen, John Hallett (Desert Research Institute)

The problem: Very light snowfalls or freezing drizzle events are hard to quantify with traditional weight-triggered snow gauges. Delays of up to 30 minutes can occur before a gauge is "tipped" and the precipitation is reported. Snow that sticks to the side of the gauge can reduce the amount measured by up to 70%. Traditional gauges can't distinguish between snow and freezing drizzle.

The solution: This automated system uses an open-ended cylinder containing a hot plate that melts and evaporates snow and ice that fall into the cylinder. The plate is heated to near 90°C (194°F) by an electric current. The extra current needed to melt snow and ice is measured and compared to the current that flows through an identical, downward-pointing plate that collects no snow or ice. The difference in currents between the two plates is proportional to the rate of frozen liquid water (snow, freezing rain, or freezing drizzle) accumulating on the upper plate. A fan beneath the hot plate pulls air downward, preventing any updrafts that could affect the precipitation rate.

Frozen Precipitation Accumulation Alert System

Patent No. 5,850,619, issued 15 December

Inventor: Roy Rasmussen, Wayne Adams (formerly of RAP, now at INFACT Technologies), Jeff Cole, Frank Hage, and Chuck Wade

The problem: Ice accumulating on aircraft is a significant aviation hazard. As little as 0.8 millimeters (0.03 inch) of ice on a wing surface can increase drag and reduce airplane lift by 25%. The standard descriptions of snowfall rate in NWS observations (light, moderate, heavy) are based on visibility. However, research shows that the amount of liquid water contained in snow is a better indicator of the potential for hazardous icing.

The solution: This system (Weather Support to Deicing Decision Making, or WSDDM) provides nowcasts of snowfall rate and other weather variables in an easy-to-use graphical format. It uses data from Doppler radars, surface weather stations, and snow gauges such as the one described above. The expected movements of radar-indicated snow bands are shown, along with a 30-minute forecast of snowfall intensity. The displays can be used by airline meteorologists, dispatch and deicing personnel, municipal workers, and air traffic controllers.

Virtual Reality Imaging System with Image Replay

Patent No. 5,751,289, issued 12 May

Inventor: Bill Myers

The problem: Computer graphics continue to grow in sophistication, but their usefulness in depicting complex, real-world features in real time is still constrained by processing time and storage ability. It's particularly challenging to follow a three-dimensional event such as a microburst through its evolution in real time. Typical storage methods don't allow the user to modify or manipulate images to show such an event from different perspectives.

The solution: This imaging system, developed with aviation applications in mind, allows a user to view a 3-D phenomenon and watch it unfold in virtual reality from a selected point in space, such as the cockpit of a plane approaching an airport runway. The display can be adjusted to highlight only the variables of most interest. Data are stored in a compact format that allows for quick replay of an event with only modest memory requirements. This system expands upon Bill's previous Virtual Reality Imaging System, patented in 1996, by allowing sequences to be replayed from different perspectives.

Ice Detection using Radiometers

Patent No. 5,777,481, issued 7 July

This diagram outlines the radiometer-based ice detection scheme created by Jothiram Vivekanandan. Three sources of downwelling radiation--scattering from ice crystals and emissions from both water droplets and water vapor--are tracked by separate microwave channels. A computer algorithm then adjusts the data and reports the prevalence of each mode (vapor, liquid, or ice) in the atmosphere above.

Inventor: Jothiram Vivekanandan

The problem: Ground-based radiometers intercept downwelling radiation at key frequencies, which allows scientists to estimate the amount of water vapor and liquid water in the atmosphere above. Although they provide continuous measurements, most radiometer techniques cannot detect the ice phase, so their estimates of liquid are unreliable when ice is present. This limits their usefulness in research and in diagnosing the risk of aircraft icing.

The solution: This system uses a radiometer with three frequency channels. Each is sensitive to a different phase of water (liquid, solid, or vapor). The three channels allow the separation of radiative effects from ice, water, and water vapor and provide a reliable estimate of the amounts of water aloft in each state. The system accounts for the scattering effect of ice particles and the absorption and emission of radiation by liquid water and water vapor. It can be used to help detect supercooled droplets that pose an aircraft icing threat and to study water-phase transitions and other problems in microphysics. •

In this issue...
Other issues of Staff Notes Monthly


Edited by Bob Henson, bhenson@ucar.edu
Prepared for the Web by Jacque Marshall