Friday, July 20, 2007

Clinometers and tree height

A look at some of our stately giants

Posted Sunday, July 15, 2007

The second largest Osage orange tree in the country is at Hagley Museum. Danielle Quigley

Americans have a fascination with the biggest, equating it with the best. The United States is home to the world's biggest ball of twine, T-rex skeleton and disco ball. And we catalog our natural wonders by size, too. Since the 1940s, the nonprofit group American Forests has been documenting the largest known specimens of 826 species of trees. A listing of these champions can be found at the National Register of Big Trees ( resources/bigtrees). There's a 128-foot balsam poplar in Minnesota, a 141-foot red maple in Great Smoky National Park, but, alas, not a single Delaware tree in the registry.

But that doesn't mean our trees are puny. "From pre-colonial days, Delaware was primarily deciduous broad-leaf forest," says Dr. Sue Barton, University of Delaware Cooperative Extension specialist in ornamental horticulture. "Much of this wooded land has been lost to development, but tracts of old forest survive.

"So, although we may not have the nation's champion tree in any particular species, we certainly have a greater number of big trees than you'll find in Midwestern states that were originally prairie land."

The state has been keeping track of its own champion trees for decades. "Big Trees of Delaware," available online at forestry/forms/bigtrees.pdf, is a guide to the First State's champions, produced by a team from the Delaware Forest Service, including urban forestry coordinator Henry Poole, who contributed to the third, and most recent, edition.

"The guide is a way to draw attention to the state's biggest trees and get citizens interested in tree preservation," says Poole. "It was fun to put together, and people tell us it's a lot of fun to use."

Pore through its 69 pages and you'll discover that the state's tallest tree is a 166-foot yellow poplar at Winterthur Museum. But this poplar isn't the biggest tree in the state, as height is only one factor in what constitutes a big tree. Foresters also consider the trunk circumference and the average crown spread, using a formula to come up with the total points earned by a tree.

And, in case you were wondering, foresters don't need fire truck ladders or bucket trucks to measure the tippy-top of trees. They use clinometers, devices that measure the line of sight above or below horizontal.

The biggest white pine in the state is a specimen off of Way Road in Hockessin that has a 42-foot crown spread and a height of 124 feet. In contrast, the champion redbud tree, located at Hagley Museum, has a crown spread of 41 feet and is just 47 feet tall.

"It's all relative," says Barton. "As a species, redbuds are a lot smaller than white pine. Redbuds usually top out at about 30 feet tall, so 47 feet is pretty impressive."

One of Poole's favorite champion trees is remarkable for its circumference, not its height. A Japanese zelkova tree, located on a private estate in Greenville, has a circumference of 318 inches. "It's like no other zelkova I've ever seen," raves Poole.

Another one of Poole's favorites is an Osage orange tree at Hagley Museum that is the second biggest Osage orange in the country. This stout-branched tree has a circumference of 307 inches, a crown spread of 83.5 feet and stands 66 feet tall.

They may not qualify as champions, but Sue Barton's favorite big trees are the "string of pearls" along Kennett Pike that start in Greenville and extend to the state line. These stately old elms, sycamores and oaks were planted in the 1920s by Pierre S. du Pont, who funded the construction of Kennett Pike. The trees were a birthday gift to his wife, Alice, who remarked that the string of pearls she'd like best would be a string of handsome trees.

To see some of the biggest trees in New Castle County and nearby areas, plan to attend "On the Trail of Champion Trees," a day-long guided excursion on July 26. To register, call Longwood Gardens at (610) 388-1000.

Native Delaware is a weekly column by the university's Cooperative Extension on First State plants, animals and weather. McDonough is a communications specialist for the University of Delaware. To suggest a topic or ask a question, please contact McDonough at 831-1358 or

Friday, July 13, 2007

Ball Bank Indicator for Safe Curve Speed

The term "Ball Bank Indicator" refers to an inclinometer that is used for the specific purpose of determining safe (uniform advisory) curve speeds for horizontal curves. It measures the overturning force (side friction), measured in degrees, on a vehicle negotiating a horizontal curve - whether it is an isolated curve, multiple "S" curve, or a ramp to/from a freeway. Typically used by the Department of Transportation and other advisory transportation agencies.

Rieker has been manufacturing 'ball-in-tube" style inclinometers, angle indicators and measuring instruments since 1917. The 1023W1 (shown above) has been the industry standard for ball banking and used nationwide by DOT, highway and traffic engineers. Precision tube manufactured to MIL specifications, ±20º range, accurate 1º increments. Simple to use, fast precise visual indication.

The RDS7-BB digital ball banking unit features an audible alert, an LCD displaying angle to 0.01º, RS232 output (instant readouts right to your laptop), and optional programmable trip angles - make this unit the most versatile and easy to use ball banking package available. It does not require a second operator to record the angle, the audible alarm alerts the driver allowing him to keep his eyes on the road - more cost effective and safer to operate.

Accelerometer et al: Holmwood On How In2Games Will Wii-ify 360 and PS3

Accelerometer et al: Holmwood On How In2Games Will Wii-ify 360 and PS3

Friday, July 06, 2007

projectors with ease-of-use and advanced features to maximize professional presentations

Canon Launches 3 New High-Quality XGA LCD Projectors Displays | 29th Jun 2007

Canon offers three new LCD projectors that provide the perfect solution for portable large displays

The new LV-7265, LV-7260, and LV-X7 projectors provide crisp, clear and bright projections, with ease-of-use and advanced features to maximize professional presentations

Singapore, – Canon is proud to announce the launch of three new feature-rich projectors - the LV-7265, LV-7260, and LV-X7 that provide small and home office users, government corporations and corporate users bright and high-quality XGA images.

The stellar blend of an extremely short throw distance and a powerful, yet versatile, 1.6x Canon wide-angle zoom lens, ensures bright "large-screen" high-fidelity images. The new LV projector series are well-suited for presenting graphics and video from laptop computers, videos from DVDs and VCRs or even live images from the Canon RE-455X Visualizer, which can easily be connected to Canon’s digital camcorders and digital cameras for fast, seamless video projection.

“In today’s business environment, customers not only expect advanced features in the projectors to make great presentations, but also want innovative user friendliness that makes delivering an impactful presentation easier.” says Andrew Koh, Director and General Manager of the Consumer Imaging and Information Division at Canon Singapore Pte Ltd. “Canon’s new range of LV projectors effectively meet these needs and showcase our commitment to technological research and design as these projectors are affordably engineered to provide clear and bright images with versatile ease of use for the presenters themselves.”

Perfect presentations
Canon's new LV-7265, LV-7260 and LV-X7 Projectors output high-quality XGA (1024 x 768) resolution imagery and also support UXGA (1600x1200) and SXGA (1280x1024) resolution display through high-quality compression.

The top-of-line LV-7265 Projector delivers powerful 2500 ANSI Lumens brightness and is suited to use in larger meeting rooms, boardrooms and conference rooms. The LV-7260 provides 2000 ANSI lumens whilst the LV-X7 provides 1500 ANSI lumens. With powerful lumens brightness, projections are characterised by clear images and text, even in daylight or adverse ambient light.

Clear and bright projection
To effectively eliminate flare, ghosting and distortion that can degrade images and distract audiences, the projectors are fitted with anti-glare coating and twin aspherical optical elements.

All three projectors also feature flexible image settings with five automatic image modes (Presentation, Video, Cinema, Standard, sRGB) and manual settings for each mode to create custom presets to accomplish the perfect presentation.

On top of that, the LV-7260 and LV-X7 projectors feature Vertical Keystone Correction to eliminate trapezium distortion in spaces where the projector cannot be positioned perpendicular to the screen. The higher-end LV-7265 performs this task automatically using a built-in tilt sensor.