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Part III, Chapter 8 of the book "Managing Enterprise Risk: What the Electric Industry Experience Implies for Contemporary Business" is presented. It mentions that the instruments of risk management, which are used in the energy industry, were derived from the tools, which are used in banking sector and cites the similarities between the two industries in terms of risk management system.

In this communication we present the activities related to the development of fuzzy logic based systems at the Microelectronics Institute of Seville (Spain). These activities regard with the design of circuits and systems that operate in fuzzy logic, the development of CAD tools for fuzzy logic and the accomplishment of applications that use fuzzy logic in the resolution of certain problems. [ABSTRACT FROM AUTHOR]

In this paper we illustrate a fuzzy logic system design strategy based on a high level description. Employing this high level description, the knowledge base is described in a language in appearance close to the natural language with the particularity that it uses a hardware description language (VHDL) directly synthesizable on an FPGA circuit. In addition, we analyze FPGA implementations of different fuzzy inference hardware architectures in order to characterize them in terms of area and speed.Partial founded by projects 58/02 de DGAECE (Junta de Andalucía) and TIC2001-1726 (CICYT). [ABSTRACT FROM AUTHOR]

Well-preserved primary textural features were recognized in cherts and jaspers that form one of the manganese ore-hosting units of the Soloviejo Mn deposit, in the Iberian Pyrite Belt. These include (i) spherulitic, (ii) banded and (iii) brecciated. The spherulites (0.04—0.3 mm) consits of a central core of minute grains of hematite or quartz, rimmed by chalcedony or microcrystalline quartz. Banded jaspers show no spherulitic textures. Banded textures are made up by alterations of micro- to meso-bands of silica and hematite. They often show soft-sediment deformation features, such as microslumps, pinch-and-swell, and load cast. Diagenetic brecciation overprints these pristine textures. Breccias consist of jasper fragments (mm to cm), affected by total or partial recrystalization, cemented by different proportions of microcrystalline quartz. Primary textures in siliceous hydrothermal precipitates reflect different stages of formation and diagenetic maturation of its silica gel precursor. Their interpretation helps in constraining the initial conditions assisting the hydrothermal activity at the Soloviejo deposit, and its early evolving stages. [ABSTRACT FROM AUTHOR]

Gold mineralization in the Neves Corvo copper stockworks occurs in two geochemical associations: (1) Au+Co+Bi(±Te) and (2) Au+Cu+Ag(±Hg). Type 1 gold occurs in the deeper parts of the feeder zones. Its associated mineralogical assemblage is consistent with low sulfur activity of the fluid and high temperature (360°-400°C) conditions. The second type of gold geochemical association reflects pH increase and/or temperature decrease as the fluid moves upwards in the stockwork and reaches the base of the massive sulfide Neves Corvo is accompanied by high sulfidation parageneses. These might have resulted either from the long-lived maturation of the ore-forming system, which would have led to extreme zone refining effects, and/or from the late input of an external fluid component (possibly magmatic?) in the Neves Corvo hydrothermal system. In the PACMANUS hydrothermal field, native gold also occurs in both high and low sulfidation mineral associations. Gold occurs at the seafloor level either associated with: (1) chalcopyrite+sphalerite +tennatite, or (2) chalcopyrite+bornite ± covellite. At depth, instead, gold occurs in sphalerite as small native gold inclusions (silver-poor). Following the process of copper enrichment by zone-refining, gold frequently concentrates in the borders of the sphalerite grains. [ABSTRACT FROM AUTHOR]

New Re and Os analyses of pyrites from Aljustrel, Lagoa Salgada and Neves-Corvo deposits yield concentrations that are similar to those previously reported for the Rio Tinto and Tharsis deposits, all at the Iberian Pyrite Belt. Osmium contents in IPB pyrites increase from the deeper stockwork zones towards the upper massive sulphides. Pyrite samples from IPB sulphide orebodies plot on a major 187Re/188Os-187Os/188O linear array, yielding an age of 359±26 Ma and an initial 187Os/188O ratio of ca. 0.57. Five samples from Neves-Corvo sulphide-rich stockwork ores yield an age of 358 ±29 Ma and an initial 187Os/188O ratio of 0.49 ±0.07, in accord with palynological and isotopic age constraints for ore formation at the IPB. Pyrites from Neves-Corvo copper-tin ores have Re/Os ratios and osmium concentrations that are similar to those in pyrites from sulphide-rich stockwork ores; however, their highly radiogenic initial 187Os/188O ratios (4.89-7.85, if preserving original isotope system-atics) preclude derivation from the same sources as the remaining IPB sulphides. The overall Re-Os geochemical data conform to previous Sr, Nd and Pb isotopic studies supporting multiple sources for IPB metallogenesis. [ABSTRACT FROM AUTHOR]

Mineralogical and geochemical data of hydrothermal sediments collected from the Saldanha site are presented. The Saldanha hydrothermal field is located at the top of a serpentinized massif Mount Saldanha (MS), at a non-transform offset (NTOS) along the Mid-Atlantic Ridge (MAR), south of the Azores. It is one of the rare known sites where direct evidence of low-temperature hydrothermal activity has been provided by direct observtion of hydrothermal fluid venting through small orifices in the ocean floor sedimentary cover. This study reveals that these hydrothermal sediments are highly "diluted" within dominant foraminiferal nanofossiliferous ooze and that the mineral assemblage of the hydrothermal component is characterized by sulphides, poorly crystallized Mn oxihydroxides, Mn brucite and hydrothermal clays. Sediments with a stronger hydrothermal component are located at the top of the mount, where hydrothermal activity was observed. Here the sediments are enriched in Cu, Zn and Fe sulphides, Mn-Mg oxy-hydroxides and putative manganobrucite. Total geochemical analyses show that all sediments are enriched in elements such as Mn, Fe, Cu and Zn, derived from hydrothermal fluids, Mg, P and V, scavenged from seawater, and Ni, Cr and Co derived from ultramafic rocks. Sediments collected next to the vents are particularly enriched in Mn. The geochemical data together with the observed mineral assemblage and the geological setting suggest that the hydrothermal fluids have much higher temperature than those measured at the escape orifices (max. 9°C), and a strong enrichment in Mg, mainly at the top of the mount, agrees with extensive mixing of the hydrothermal fluid with unmodified seawater. [ABSTRACT FROM AUTHOR]

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This article introduces some of the fundamental issues related to called asynchronous sequential circuits (ASCs), such as, comparison with synchronous circuits and potential advantages of ASCs, major specification and design techniques, different implementation architectures and performance characteristics. An ASC can be simply defined as a sequential circuit whose internal states change only in response to changes in its inputs, with no common timing reference. More generally, an ASC is called speed-independent when it operates correctly for any finite delay in gates. A subset of these circuits generates a completion signal indicating that its operation has finished.