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Displaying 15,441 - 15,450 of 65,184 Publications- Soft-story wood-frame buildings have been recognized as a disaster preparedness problem for decades. The majority of these buildings were constructed from the 1920s to the 1960s and are prone to collapse during moderate to large earthquakes due to a characteristic deficiency in strength and stiffness in their first story. In order to propose and validate retrofit methods for these at-risk buildings, a full-scale four-story soft-story wood-frame building was constructed, retrofitted, and subjected to ground motions of various intensities. The tests were conducted to validate retrofit...AuthorsJohn W. van de Lindt, Pouria Bahmani, Gary Mochizuki, Steven E. Pryor, Mikhail Gershfeld, Jingjing Tian, Michael D. Symans, Douglas R. RammerKeywordsSourceJournal of Structural Engineering. 142(4): 1-14Year2016
- Soft-story wood-frame buildings have been recognized as a disaster preparedness problem for decades. There are tens of thousands of these multifamily three- and four-story structures throughout California and other parts of the United States. The majority were constructed between 1920 and 1970 and are prevalent in regions such as the San Francisco Bay Area in California. The NEES-Soft project was a five-university multiindustry effort that culminated in a series of full-scale soft-story wood-frame building tests to validate retrofit philosophies proposed by (1) Federal Emergency Management...AuthorsPouria Bahmani, John W. van de Lindt, Mikhail Gershfeld, Gary L. Mochizuki, Steven E. Pryor, Douglas R. RammerKeywordsSourceJournal of Structural Engineering. 142(4): 1-14.Year2016
- Tephra fall influences the structure and dynamics of Andean Nothofagus (beech) forests in Puyehue National Park, Chile. Forest mortality and subsequent establishment, structure and composition have been affected by the eruption of the Puyehue-Cordon Caulle volcano complex.AuthorsMauricio Montiel, Mauro E González, Charlie CrisafulliKeywordsSourceAnales del Instituto de la Patagonia. 44(3): 5-11.Year2016
- The concept of iso- vs. anisohydry has been used to describe the stringency of stomatal regulation of plant water potential (ψ). However, metrics that accurately and consistently quantify species’ operating ranges along a continuum of iso- to anisohydry have been elusive. Additionally, most approaches to quantifying iso/anisohydry require labour-intensive measurements during prolonged drought. We evaluated new and previously developed metrics of stringency of stomatal regulation of ψ during soil drying in eight woody species and determined whether easily-determined leaf pressure–volume...AuthorsFrederick Meinzer, David R. Woodruff, Danielle E. Marias, Duncan D. Smith, Katherine A. McCulloh, Ava R. Howard, Alicia L. Magedman, Josep PenuelasKeywordsSourceEcology Letters. 19(11): 1343-1352.Year2016
- The growing demand for alternative energy has led those who are interested in producing sustainable energy from renewable timber to devise new concepts to satisfy those demands. The concept of timber processing depots, where whole stem trees will be delivered for future processing into wood products and high quality energy fuel, has led to the re-evaluation of our current timber transportation method and whether it can viably transport unprocessed trees in an efficient, legal and safe manner. Modifications for log trailers will be developed to accommodate tree length, unprocessed southern...AuthorsJohn Lancaster, Tom Gallagher, Tim McDonald, Dana MitchellKeywordsSourceIn: Proceedings of the 2016 COFE and DEMO International Conference, “Canada’s Forest Sector: Adapting to a New Reality”. 9/19 – 9/21/16, Vancouver, B.C. CANADA.Year2016
- Renewable fuels are being tested as an alternative for fossil fuels. For the Southeast U.S., the use of woody biomass has proven to be an excellent source of renewable energy in terms of cost benefit and availability. Short rotation woody crops (SRWC) are timber plantations with exclusive characteristics that can meet the intensive demand for wood due to their fast growth and ability to coppice. Generally, SRWC require more maintenance than other popular woody crops, which might increase the cost of establishment for each new cycle of rotations. However,due to their coppicing ability, the...AuthorsRafael Santiago, Tom Gallagher, Matthew Smidt, Dana MitchellSourceIn:Proceedings of the 2016 COFE and DEMO international conference, “Canada’s forest sector: Adapting to a new reality”. 9/19 – 9/21/16, Vancouver, B.C. Canada.Year2016
- Fire managers are continuously looking for improved methods to construct fireline with minimal resource damage. One option for fireline construction that has so far received limited attention is the use of mastication equipment. This study evaluated a masticating disk mounted on a self-leveling feller- buncher for the cost, speed, and adherence to fireline specifications while constructing approximately 5 miles of fieline across a range of terrain and fuel types. Field trials were conducted during the fall of 2015 on the University of Montana’s Bandy Experimental Ranch. Production rates...AuthorsElizabeth Dodson, Dana MitchellSourceIn:Proceedings of the 2016 COFE and Demo International 2016 Technical Conference, Canada’s Forest Sector, Adapting to a New Reality. Vancouver, BC, CanadaYear2016
- Felling and skidding operations were monitored while clearcut harvesting a 12-acre area of a 14-year old loblolly pine (Pinus taeda) plantation. The study area contained 465 trees per acre for trees 2.0 inches Diameter at Breast Height (DBH) and larger with a Quadratic Mean Diameter (QMD) of 7.26 inches. Two feller-bunchers (tracked and rubber-tired) and two skidders (conventional and large capacity) were paired to create four different harvesting systems which were randomly assigned to 3-acre units for evaluation of production rates and costs. Each system was balanced to determine the...AuthorsJohn Klepac, Dana MitchellKeywordsSourceProfessional Agricultural Workers JournalYear2016
- Temporal changes in the relative abundances of host–parasite populations can influence the magnitude of the effects of corresponding interspecific interactions. When parasite populations are at relatively low abundance, the negative effects on host populations may be insignificant, but when parasite abundance increases beyond critical thresholds, they can have population limiting effects on the host. Here, we used data from a 40‐yr demographic study on breeding Wood Thrushes (Hylocichla mustelina) and avian brood parasitic Brown‐headed Cowbirds (Molothrus ater) in the mid‐Atlantic United...AuthorsZachary S. Ladin, Vince D'Amico, Jan M. Baetens, Roland R. Roth, W. Gregory. ShriverKeywordsSourceEcosphereYear2016
- This meeting was the 27th in a series of annual USDA Interagency Research Forums that are sponsored by the Forest Service, Animal and Plant Health Inspection Service, National Institute of Food and Agriculture, and Agriculture Research Service. The Group’s original goal of fostering communication and providing a forum for the overview of ongoing research among the Agencies and their cooperators continues to be realized and facilitated through this meeting. This proceedings documents the efforts of many individuals: those who organized and sponsored the meeting, those who provided oral and...AuthorsKatherine A. McManusSourceFHTET-2016-09. Morgantown, WV: U.S. Department of Agriculture, Forest Service, Forest Health Technology Enterprise Team. 107 p.Year2016