| State of timber: Tracing history of an industry in decline
Editor's note: Over the past three decades, the national forest timber harvest has crashed. Some blame environmental regulation. Others blame overharvest in the 1970s and 1980s. Still others point to supply-and-demand economics, and an emergent international import-export lumber business. But most agree the U.S. Forest Service's Northern Region - where harvest has been reduced from 1.2 billion board feet to just 114 million - could produce far more logs if the market would bear them. How to get at that timber, however, remains a point of considerable controversy. Today, the Missoulian begins a four-day series looking at timber cutting in western Montana.KALISPELL - About a month ago, a brand-new Bitterroot Valley-based group rallied up in Hamilton, calling for more trees to be cut from national forests.A whole lot of people turned out.
Emmy Award-winning speaker talks about importance of environmental ...
The path to sustainability comes one step at a time, said David Chameides, environmentalist, worm cultivator and personal garbage collector. The Emmy Award Winner and now-public speaker told a packed crowd at Chico State University Thursday about things each person can do to make a small impact on global warming. Contemplating the amount of energy used on earth is too big for any one person to dwell upon, he explained. But creating easy-to-form habits now will make life easier on future generations. Americans use 26 percent of the power in the world, he said, which is "unacceptable." "This is not hard stuff. It just takes a different type of thinking," he said. Some easy steps: Use less electricity. Because electricity is ubiquitous, people do not think abut where it comes from and the resources used to create it.
Comparison of linear actuators with pneumatics and hydraulics
Over the past few years the development of electric linear actuators has led to their increasing use in linear motion systems that would formerly have used hydraulics. When deciding whether to use hydraulic or electro-mechanical actuators in a particular application the sole deciding factor is: which best meets the technical and economic demands of the application. Although the features of each application need to be examined individually, the table provided with this article makes clear the several variables that will influence the basic decision and need to be considered when designing a linear motion system. A system for a fully electric powered fork-lift truck is taken as an example. In a growing number of instances, the basic question to be answered when designing a linear motion system is whether to use electro-mechanical actuators or hydraulic.
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