The use of wood for wind turbine blade construction

The interrelationships between moisture and wood, conditions for dry rot spore activity, the protection of wood fibers from moisture, wood resin composites, wood laminating, quality control, and the mechanical properties of wood are discussed. The laminated veneer and the bonded sawn stock fabrication techniques, used in the construction of a turbine blade with a monocoque 'D' section forming the leading edge and a built up trailing edge section, are described. A 20 foot root end sample complete with 24 bonded-in studs was successfully subjected to large onetime loads in both the flatwise and edgewise directions, and to fatigue tests. Results indicate that wood is both a viable and advantageous material for use in wind turbine blades. The basic material is reasonably priced, domestically available, ecologically sound, and easily fabricated with low energy consumption

Assurance et diversification

Le domaine du risk management se limite traditionnellement aux risques purs, par opposition aux risques spéculatifs qui proviennent des aléas du marché. L’objectif de cet article est de mettre en évidence la perte d’efficience qui peut résulter d’une gestion cloisonnée et indépendante de ces deux catégories de risques. Nous proposons un modèle global, inspiré de l’approche portefeuille, au sein duquel différents types d’actions influençant le niveau de risque de la firme sont envisagées simultanément : allocation des ressources entre plusieurs activités, choix d’une structure financière, achat d’assurance. Ce modèle permet d’étudier les arbitrages entre les différentes modalité de réduction du risque. Des conclusions précises sont énoncées, elles concernent principalement la détermination du budget assurances et son allocation.The field of risk management is usually restricted to the pure risks, opposed to speculative risk due to the market uncertainties. The aim of this article is to evidence the lack of efficiency which may result if pure risks are handled separately and independently. We refer to the portfolio approach to build a global model in which different kinds of decisions influencing the final risk level of the firm are simultaneously considered (such as resources allocation between diversified activities, debt ratio and insurance coverage). The main conclusions concern the optimal level of the insurance expenditures and their allocation between risks

Co-management of the migratory caribou herds in northern Québec: The perspective of the Hunting, Fishing and Trapping Coordinating Committee

Aboriginal people have a long relationship with caribou, and caribou - especially the large migratory herds- cross aboriginal territories and jurisdictional boundaries. These two points are key to understanding the intricacies and complexities of managing caribou

Whitman, Emerson, and "The Ballad of the Abolition Blunder-buss"

Contrasts Whitman\u27s and Emerson\u27s attitudes towards abolition and details the attitudes toward African-Americans that Whitman encountered in Boston; concludes by presenting a "scurrilous satirical work called \u27Ballad of the Abolition Blunder-buss.\u27

Whitman, Emerson, and "The Ballad of the Abolition Blunder-buss"

Contrasts Whitman\u27s and Emerson\u27s attitudes towards abolition and details the attitudes toward African-Americans that Whitman encountered in Boston; concludes by presenting a "scurrilous satirical work called \u27Ballad of the Abolition Blunder-buss.\u27

Emerson, Whitman, and Eros

Seeks to correct the "sanitzed and stilted view of Emerson" that prevailed among Emerson\u27s Brahmin friends and still dominates much Whitman criticism, and argues that Emerson and Whitman share a belief in "the body and the senses" as "essential elements of human nature"; using Norman O. Brown\u27s theories, goes on to posit that for Emerson and Whitman "one of the primary drives of Eros . . . is desire for union with the world, with the natural environment," and that both writers sought a "sensual language" to express this desire: "For both Emerson and Whitman, humanity must literally come to its senses, in word and deed.

Whitman and the Commonwealth

Presents a neglected article from the April 10, 1863, issue of the Commonwealth advocating Whitman\u27s work; describes Whitman\u27s relation to publishers Thayer and Eldridge and other abolitionists including John Townsend Trowbridge, William Douglas O\u27Connor and Franklin Benjamin Sanborn

Forest Remote Sensing in Canada and the Individual Tree Crown (ITC) Approach to Forest Inventories

After a brief description of Canada’s forest situation and the role of the federal government in forestry, some Natural Resources Canada’country-wide project will be introduced. These include the National Forest Inventories (past and present), the National Forest Information System, the EOSD programs to map land cover, monitor change and evaluate biomass, mostly from Canada-wide coverages with Landsat images. The accounting of carbon and the monitoring of deforestation at a map scale level will also be introduced. The second and most significant part of this paper will describe our Individual Tree Crown (ITC) approach to forest inventories used with high spatial resolution images (better than 1m/pixel). Techniques for individual crown delineation, species classification and regrouping into forest stands that are leading to a semi-automatic production of forest inventories will be described.A locally adaptive technique for tree counts, mostly reserved for young regenerating areas, will also be presented. The synergy of multispectral and LIDAR data (atmany levels) will be examined and, the normalization of spectral values within and among aerial images will be considered.Article信州大学農学部紀要. 46(1-2): 85-92 (2010)departmental bulletin pape

Assurance et diversification

The field of risk management is usually restricted to the pure risks, opposed to speculative risk due to the market uncertainties. The aim of this article is to evidence the lack of efficiency which may result if pure risks are handled separately and independently. We refer to the portfolio approach to build a global model in which different kinds of decisions influencing the final risk level of the firm are simultaneously considered (such as resources allocation between diversified activities, debt ratio and insurance coverage). The main conclusions concern the optimal level of the insurance expenditures and their allocation between risks. Le domaine du risk management se limite traditionnellement aux risques purs, par opposition aux risques spéculatifs qui proviennent des aléas du marché. L’objectif de cet article est de mettre en évidence la perte d’efficience qui peut résulter d’une gestion cloisonnée et indépendante de ces deux catégories de risques. Nous proposons un modèle global, inspiré de l’approche portefeuille, au sein duquel différents types d’actions influençant le niveau de risque de la firme sont envisagées simultanément : allocation des ressources entre plusieurs activités, choix d’une structure financière, achat d’assurance. Ce modèle permet d’étudier les arbitrages entre les différentes modalité de réduction du risque. Des conclusions précises sont énoncées, elles concernent principalement la détermination du budget assurances et son allocation.

Fabrication of low-cost Mod-OA wood composite wind turbine blades

The wood composite blades were fabricated by using epoxy resin-bonded laminates of Douglas fir veneers for the leading edge spar sections and honeycomb-cored birch plywood panels for the blade trailing edge or afterbody sections. The blade was joined to the wind turbine hub assembly by epoxy resin-bonded steel load take-off studs. The wood composite blades were installed in the Mod-OA wind turbine test facility at Kahuku, Hawaii. The wood composite blades have successfully completed high power (average of 150 kW) operations for an eighteen month period (nearly 8,000 hr) before replacement with another set of wood composite blades. The original set of blades was taken out of service because of the failure of the shank on one stud. An inspection of the blades at NASA-Lewis showed that the shank failure was caused by a high stress concentration at a corrosion pit on the shank fillet radius which resulted in fatigue stresses in excess of the endurance limit