392 research outputs found
A supply and demand model of bilateral trade in a multicountry framework
This study develops a practical supply and demand model of bilateral trade flows. The model is constructed in two tiers. First, aggregate import demand and aggregate export supply are determined from aggregate economic relations that contain real income (output) and relative prices. Second, bilateral import demand and bilateral export supply are determined from theory-based allocation relations. By differentiating import prices from export prices, the analysis incorporates international transportation costs and tariffs. The result is a simultaneous system that determines bilateral trade flows and bilateral prices given country incomes, domestic price levels and international transmission factors. The model in dynamic form is estimated from a panel of bilateral trade flows for five major OECD countries (United States, Japan, France, West Germany, United Kingdom) for the years 1958-1971. The model has many applications, e.g. in the analyses of the impacts on trade flows of differential economic growth rates and tariff policies. These policy aspects figure prominently in the current discussions among the major OECD countries.
Research on graphite reinforced glass matrix composites
A broad group of fibers and matrices were combined to create a wide range of composite properties. Primary material fabrication procedures were developed which readily permit the fabrication of flat plate and shaped composites. Composite mechanical properties were measured under a wide range of test conditions. Tensile, flexure mechanical fatigue, thermal fatigue, fracture toughness, and fatigue crack growth resistance were evaluated. Selected fiber-matrix combinations were shown to maintain their strength at up to 1300 K when tested in an inert atmosphere. Composite high temperature mechanical properties were shown to be limited primarily by the oxidation resistance of the graphite fibers. Composite thermal dimensional stability was measured and found to be excellent
Allokationseffekte rechtlich-institutioneller Regelungen der Meeresnutzung: Vorbereitet für die Arbeitstagung des Vereins für Socialpolitik 1979 in Mannheim, 24. - 26.9.1979
Research on graphite reinforced glass matrix composites
A composite that can be used at temperatures up to 875 K with mechanical properties equal or superior to graphite fiber reinforced epoxy composites is presented. The composite system consist of graphite fiber, uniaxially or biaxially, reinforced borosilicate glass. The mechanical and thermal properties of such a graphite fiber reinforced glass composite are described, and the system is shown to offer promise as a high performance structural material. Specific properties that were measured were: a modified borosilicate glass uniaxially reinforced by Hercules HMS graphite fiber has a three-point flexural strength of 1030 MPa, a four-point flexural strength of 964 MPa, an elastic modulus of 199 GPa and a failure strain of 0.0052. The preparation and properties of similar composites with Hercules HTS, Celanese DG-102, Thornel 300 and Thornel Pitch graphite fibers are also described
Research on Graphite Reinforced Glass Matrix Composites
This report contains the results obtained in the first twelve months of research under NASA Langley Contract NAS1-14346 for the origination of graphite-fiber reinforced glass matrix composites. Included in the report is a summary of the research by other investigators in this area. The method selected to form the composites consisted of pulling the graphite fiber through a slurry containing powdered glass, winding up the graphite fiber and the glass it picks up on a drum, drying, cutting into segments, loading the tape segment into a graphite die, and hot pressing. During the course of the work, composites were made with a variety of graphite fibers in a C.G.W. 7740 (Pyrex) glass matrix. The graphite fibers used included Hercules HMS, Hercules HTS, Thornel 300S, and Celanese DG-102 and, of these, the Hercules HMS and Celanese DG-102 graphite fibers in C.G.W. 7740 gave the most interesting but widely different results. Hercules HMS fiber in C.G.W. 7740 glass (Pyrex) showed an average four-point flexural strength of 848 MPa or 127,300 psi. As the test temperature was raised from room temperature to 560 C in argon or vacuum, the strength was higher by 50 percent. However, in air, similar tests at 560 C gave a severe loss in strength. These composites also have good thermal cycle properties in argon or vacuum, greatly increased toughness compared to glass, and no loss in strength in a 100 cycle fatigue test. Celanese DG-102 fiber in C.G.W. 7740 glass (Pyrex) had a much lower flexural strength but did not suffer any loss in this strength when samples were heated to 560 C in air for 4 hrs
Gibt es eine nicht-individualistische Handlungstheorie? Bemerkung über handlungs- oder strukturtheoretische Begriffsbildung in der Soziologie ; Kurzfassung
The regional impact of the EEC fisheries policy. The economic and social situation and outlook for the fisheries sector in certain regions of the Community: Schleswig-Holstein. Internal information on fisheries 6
A New SiC-Whisker-Reinforced Lithium Aluminosilicate Composite
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65747/1/j.1151-2916.1993.tb04016.x.pd
Fibrous Monolithic Ceramics: III, Mechanical Properties and Oxidation Behavior of the Silicon Carbide/Boron Nitride System
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66176/1/j.1151-2916.1994.tb05399.x.pd
Distribution of Matrix Cracks in a Uniaxial Ceramic Composite
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65596/1/j.1151-2916.1992.tb08181.x.pd
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