Data analysis advances in marine science for fisheries management : supervised classification application

169 p. : il. col.

Algorithms for colour image processing based on neurological models

373 p. : il., gráf., fot., tablas

Magnitude and Extent of Contaminated Sediment and Toxicity in Chesapeake Bay

INTRODUCTION: This report summarizes the results of NOAA's sediment toxicity, chemistry, and benthic community studies in the Chesapeake Bay estuary. As part of the National Status and Trends (NS&T) Program, NOAA has conducted studies to determine the spatial extent and severity of chemical contamination and associated adverse biological effects in coastal bays and estuaries of the United States since 1991. Sediment contamination in U.S. coastal areas is a major environmental issue because of its potential toxic effects on biological resources and often, indirectly, on human health. Thus, characterizing and delineating areas of sediment contamination and toxicity and demonstrating their effect(s) on benthic living resources are viewed as important goals of coastal resource management. Benthic community studies have a history of use in regional estuarine monitoring programs and have been shown to be an effective indicator for describing the extent and magnitude of pollution impacts in estuarine ecosystems, as well as for assessing the effectiveness of management actions. Chesapeake Bay is the largest estuarine system in the United States. Including tidal tributaries, the Bay has approximately 18,694 km of shoreline (more than the entire US West Coast). The watershed is over 165,000 km2 (64,000 miles2), and includes portions of six states (Delaware, Maryland, New York, Pennsylvania, Virginia, and West Virginia) and the District of Columbia. The population of the watershed exceeds 15 million people. There are 150 rivers and streams in the Chesapeake drainage basin. Within the watershed, five major rivers - the Susquehanna, Potomac, Rappahannock, York and James - provide almost 90% of the freshwater to the Bay. The Bay receives an equal volume of water from the Atlantic Ocean. In the upper Bay and tributaries, sediments are fine-grained silts and clays. Sediments in the middle Bay are mostly made of silts and clays derived from shoreline erosion. In the lower Bay, by contrast, the sediments are sandy. These particles come from shore erosion and inputs from the Atlantic Ocean. The introduction of European-style agriculture and large scale clearing of the watershed produced massive shifts in sediment dynamics of the Bay watershed. As early as the mid 1700s, some navigable rivers were filled in by sediment and sedimentation caused several colonial seaports to become landlocked. Toxic contaminants enter the Bay via atmospheric deposition, dissolved and particulate runoff from the watershed or direct discharge. While contaminants enter the Bay from several sources, sediments accumulate many toxic contaminants and thus reveal the status of input for these constituents. In the watershed, loading estimates indicate that the major sources of contaminants are point sources, stormwater runoff, atmospheric deposition, and spills. Point sources and urban runoff in the Bay proper contribute large quantities of contaminants. Pesticide inputs to the Bay have not been quantified. Baltimore Harbor and the Elizabeth River remain among the most contaminated areas in the Unites States. In the mainstem, deep sediment core analyses indicate that sediment accumulation rates are 2-10 times higher in the northern Bay than in the middle and lower Bay, and that sedimentation rates are 2-10 times higher than before European settlement throughout the Bay (NOAA 1998). The core samples show a decline in selected PAH compounds over the past several decades, but absolute concentrations are still 1 to 2 orders of magnitude above 'pristine' conditions. Core data also indicate that concentrations of PAHs, PCBs and, organochlorine pesticides do not demonstrate consistent trends over 25 years, but remain 10 times lower than sediments in the tributaries. In contrast, tri-butyl-tin (TBT) concentrations in the deep cores have declined significantly since it=s use was severely restricted. (PDF contains 241 pages)

The Economics of Gasification: A Market-Based Approach

This paper deals with the economics of gasification facilities in general and IGCC power plants in particular. Regarding the prospects of these systems, passing the technological test is one thing, passing the economic test can be quite another. In this respect, traditional valuations assume constant input and/or output prices. Since this is hardly realistic, we allow for uncertainty in prices. We naturally look at the markets where many of the products involved are regularly traded. Futures markets on commodities are particularly useful for valuing uncertain future cash flows. Thus, revenues and variable costs can be assessed by means of sound financial concepts and actual market data. On the other hand, these complex systems provide a number of flexibility options (e.g., to choose among several inputs, outputs, modes of operation, etc.). Typically, flexibility contributes significantly to the overall value of real assets. Indeed, maximization of the asset value requires the optimal exercise of any flexibility option available. Yet the economic value of flexibility is elusive, the more so under (price) uncertainty. And the right choice of input fuels and/or output products is a main concern for the facility managers. As a particular application, we deal with the valuation of input flexibility. We follow the Real Options approach. In addition to economic variables, we also address technical and environmental issues such as energy efficiency, utility performance characteristics and emissions (note that carbon constraints are looming). Lastly, a brief introduction to some stochastic processes suitable for valuation purposes is provided.

Valor de la Información. Cantidad óptima de información. Valor de la flexibilidad

El documento es de utilidad para los estudiantes de la asignatura de Economía de la Información y para cualquier estudiante o persona interesada en problemas de decisión bajo incertidumbre estáticos o dinámicos. El documento está estructurado en ocho secciones. Entre los temas analizados se incluyen: cálculo del valor de servicios de información, completa o incompleta, en varios contextos y problemas distintos, análisis del proceso de revisión de creencias cuando se recibe información, consideración de situaciones en las que la incertidumbre tiene varios componentes o en las que el decisor recibe varias informaciones simultáneamente, determinación del nivel de información que es óptimo para el decisor y cálculo del valor de la flexibilidad cuando la información llega con el paso del tiempo. Se incluyen también catorce Ejercicios que aplican los análisis desarrollados. Cada Ejercicio se presenta con su solución, a veces en forma abreviada. El documento se completa con unas Lecturas recomendadas.

Los pueblos indígenas en el constitucionalismo guatemalteco : grandes ausencias y pequeñas presencias

725 p.

Dinámicas en la producción de conocimiento : movilidad, redes y actividades de investigación en el mercosur, Chile y España

212 p.

Los estudios de segunda enseñanza en Guipuzcoa. El Instituto Provincial (1845-1901)

pág. var.

Miradas y tensiones en los paisajes del valle de Carranza

341 p.

El perfil del periodista vasco y su formación en el ámbito social de la inmigración

279 p. + anexos

Ajuste psicológico y salud mental de la población inmigrante : influencia del género y la cultura

481 p.

Estudios sobre identidad nacional en el Perú y sus correlatos psicológicos, sociales y culturales

322 p.

Sustitución del gen nirA entre cianobacterias termofílicas. Clonación, expresión y purificación de la nitrito reductasa de Thermosynechococcus elongatus BP-1

220 p.

Failure detectors and communication efficiency in the crash and general omisión failure models

122 p.

Contributions to the analysis and segmentation of remote sensing hyperspectral images

142 p.