An Experiment in Model Driven Architecture for e-Enterprise Systems

OMG's Model Driven Architecture demonstrates how a system's specification model can be used within the process of creating supporting software implementations. This article documents the findings of an experiment aimed at determining the extent to which this method of software engineering can be used within the domain of e-Enterprise systems

Declining Output Volatility: What Role for Structural Change?

The decline in output volatility in a number of countries over the past few decades has been well-documented, though less agreement has been reached about the causes of this decline. In this paper, we use a panel of data from 20 OECD countries to see if there is a role for various indicators of structural reform in explaining the general decline in output volatility. We suggest that reforms in product and labour markets can reduce volatility of aggregate output by encouraging productive resources to shift more readily in response to differential shocks across firms and sectors. In contrast to other studies, we include direct measures of product market regulations and monetary policy regimes as indicators of structural reform. We find that less product market regulation and stricter monetary policy regimes have played a role in reducing output volatility. Our estimates are reasonably robust to a number of alternative specifications, including those that attempt to control for a possible trend in common (unexplained) innovations to output volatility such as a possible decline in the magnitude of global shocks.business cycles; volatility; panel regression; structural reform; monetary policy; OECD

Induced decay of the neutral vaccum in overcritical fields occurring in heavy-ion collisions

In critical or nearly critical heavy-ion collisions, induced as well as spontaneous energyless e-e+ pair creation result in the decay of the neutral vacuum. Induced transitions from the negative-energy continuum into a vacant molecular 1s level can occur even in the absence of diving and produce a substantial enhancement and broadening of the previously considered spontaneous positron spectrum. Total cross sections of 5 b have been calculated for U-U collisions

Comparing Virus Ultrafiltration of Bacteriophages with Filtration of Minute Virus of Mice

Industrial production of protein therapeutics demand rigorous testing and clearance of viruses. The U.S. Food and Drug Administration dictate the purity of pharmaceuticals with regards to viral contamination. As this testing is time consuming and expensive using mammalian cells and viruses, bacteriophages may provide a faster and cheaper alternative for membrane filtration processes. We used ultrafiltration membranes to filter protein solutions with viruses. Two bacteriophages were tested against membranes with two different pore sizes. These membranes were then tested by inverting the membrane\u27s orientation. Flux measurements and log virus removal data were taken. Flux and log virus removal were seen to be slightly higher than published data for mammalian virus analogue minute virus of mice. Future testing would allow for more precise evaluation, but data suggests bacteriophages provide similar results to mammalian data

The natural resources of Agua Hedionda Lagoon

This report has been prepared under contract to and fully funded by the Office of Biological Services of the U. S. Fish and Wildlife Service. The goals and purpose of this federal office are to review the impact on fish and wildlife resources of land, mineral and water development practices, such as offshore oil and gas exploration, development and production; construction of inshore pipeline canals and refineries; power plant construction/operation and urban development. This report, and five other southern California reports, covering Carpinteria Marsh (Santa Barbara County), Anaheim Bay-Huntington Harbor (Orange County), Mugu Lagoon (Ventura County), the Northern Santa Barbara County Coastal Wetlands, and the Nipomo Dunes and Wetlands (San Luis Obispo County), are scheduled to be part of the Department's "Coastal Wetland Series" (see inside front cover). (154 pp.

Structure and Petrology of Tertiary Volcanic Rocks Near Etna, Utah

Three volcanic domes and related volcanic rocks of Tertiary age are located near Etna, Utah, in Box Elder County. The domes follow a north-south trend and are fault controlled. Flow structure indicates a change from a less viscous, flow-forming lava which produced an exogenous dome to a more viscous lava which formed endogenous domes. Associated pyroclastic deposits are negligible. The volcanic rocks are composed of porphyritic rhyolite and rhyolitic vitrophyre having phenocrysts of quartz, sanidine, plagioclase and biotite with minor amounts of Fe-Ti oxides, hypersthene, allanite and calcic amphibole. Quartz and sanidine phenocrysts are generally embayed whereas plagioclase phenocrysts are euhedral and extensively zoned. Average whole-rock chemical analyses yield: SiO2, 77.13; TiO2, 0.12; Al2O3, 11.01; Fe2O3, 0.9; FeO, 0.35; MnO, 0.02; MgO, 0.19; CaO, 0.82; Na2O, 2.93; K2O, 4.99; P2O5, 0.03; H2O+, 1.17; H2O-, 0.22; total, 99.94 weight percent. Coexisting Fe-Ti oxide microphenocrysts yield equilibration temperatures ranging from 872° to 684°C while respective log f0 2 values range from -13.5 to -19.5. These temperatures are comparable to temperatures obtained using the plagioclase-glass geothermometer at a water pressure of 1 kb. Mineral buffer reactions yield water fugacities with corresponding water pressures up to 4.9 kb. Assuming water pressure equals total pressure, calculated depths of approximately 18 km are obtained indicating an origin within the crust. High silica values and high alkali to calcium ratios indicate that ix the lavas are chemically similar to bimodal rhyolite-basalt assemblages located in other areas of the western United States. Small outcrops of basalt, located west of the Etna area, also suggest a bimodal assemblage. Viscosity values (log n) for the south dome range from 7.05 to 10.35 suggesting that there was a change from a less viscous to a more viscous lava. Comparisons between hydrous and dry calculations indicate that falling water content as well as decreasing temperature were responsible for the change in viscosity and resulting structural changes