871 resultados para agglomeration economies
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Dynamics of contact free (levitated) drying of nanofluid droplets is ubiquitous in many application domains ranging from spray drying to pharmaceutics. Controlling the final morphology (macro to micro scales) of the dried out sample poses some serious challenges. Evaporation of solvent and agglomeration of particles leads to porous shell formation in acoustically levitated nanosilica droplets. The capillary pressure due to evaporation across the menisci at the nanoscale pores causes buckling of the shell which leads to ring and bowl shaped final structures. Acoustics plays a crucial role in flattening of droplets which is a prerequisite for initiation of buckling in the shell: Introduction of mixed nanocolloids (sodium dodecyl sulfate + nanosilica) reduces evaporation rate, disrupts formation of porous shell, and enhances mechanical strength of the shell, all of which restricts the process of buckling. Although buckling is completely arrested in such surfactant added droplets, controlled external heating using laser enhances evaporation through the pores in the shell due to thermally induced structural changes and rearrangement of SDS aggregates which reinitializes buckling in such droplets, Furthermore, inclusion of anilinium hydrochloride into the nanoparticle laden droplets produces ions which adsorb and modify the morphology of sodium dodecyl sulfate crystals and reinitializes buckling in the shell (irrespective of external heating conditions). The kinetics of buckling is determined by the combined effect of morphology of the colloidal particles, particle/aggregate diffusion rate within the droplet, and the rate of evaporation of water. The buckling dynamics leads to cavity formation which grows subsequently to yield final structures with drastically different morphological features. The cavity growth is controlled by evaporation through the nanoscate pores and exhibits a universal trend irrespective of heating rate and nanoparticle type.
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The use of sustainability indicators for evaluating sanitation systems is applied to the Erdos Eco- Town Project (EETP) in China for illustration. The EETP is the largest urban settlement in the world employing ecological sanitation, which incorporates separation of waste streams, dry toilets, and resource recovery. The EETP’s dry sanitation system is compared against the Dongsheng District’s conventional sewer and centralised STP. The two systems are compared based on technological, environmental, economic, and societal indicators. Overall, the two systems perform reasonably well from a technological perspective. The conventional system performs significantly better than the dry system with regards to land and energy requirements, and global warming potential; it also performs better based on freshwater aquatic and terrestrial ecotoxicity potentials, but by a smaller margin. The dry system has superior environmental performance based on water consumption, eutrophication potential, and nutrient and organic matter recovery. The dry system is a more costly system as it requires greater infrastructure and higher operational costs, and does not benefit from economies of scale. The waterborne system performs better based on the societal indicators largely because it is a well-established system.
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Published as an article in: Economic Inquiry, 2004, vol. 42, issue 4, pp. 602–617.
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Asia has the most productive inland fisheries in the world. The fishery sector contributes significantly to the national economies of the region. Inland fisheries also improve food security by providing a source of protein and a livelihood for millions of people in this part of the world, especially the rural poor. The purpose of this report is to provide information on the biological, economic, social and cultural values of river fisheries in the Lower Mekong Basin, and to identify the main impacts of environmental changes on these values. A review of fisheries-related literature, including project reports and gray literature, was undertaken. More than 800 documents were reviewed, and original information was extracted from 270 of them. The analysis identified a large number of localized studies leading to generic conclusions. The report addresses the basin wide issues and studies. It is then organized by nation, namely, the Chinese province of Yunnan, then Laos, Thailand, Cambodia and Vietnam. It first gives an overview of each country’s economic, fisheries and social situation, then details the values documented for river fisheries in each country.
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[ES] La apuesta de la distribución por la extensión de su marca a las categorías de productos duraderos, como electrodomésticos y productos electrónicos para el hogar, ha demostrado ser acertada, a pesar de las críticas en contra de esta estrategia. Posiblemente, la mayor familiaridad del consumidor con las marcas del distribuidor, el cambio de actitud favorable hacia éstas, la disponibilidad de la tecnología, y por qué no, la crisis económica internacional que afecta a las economías domésticas, pueden ser factores explicativos de este éxito.
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[ES] Las redes virtuales de fabricación global (RVFGs) están formadas por empresas independientes las cuales establecen entre sí relaciones de tipo horizontal y vertical, pudiendo incluso ser competidores, donde no es necesario mantener internamente grandes recursos fabriles sino gestionar y compartir eficientemente los recursos de la red.
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[ES] Las autoridades reguladoras y supervisoras de los sistemas financieros han probado diversos métodos para intentar encontrar un procedimiento eficaz en la elaboración de un sistema de alerta temprana de las crisis bancarias. Los Modelos de Regresión Logística han sido usados aunque han mostrado algunas debilidades, por lo que se necesitan nuevos y mejores métodos. La crisis bancaria ocurrida en la República Dominicana entre los años 2002 y 2004 se ha usado para comparar la eficacia de la Regresión Logística frente al uso del método Support Vector Machines (SVM) para la detección de crisis bancarias.
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CONTENTS: Learning insights from the Fisheries Resource Management Project, by Tee-Jay A San Diego. An orientation on the SIAD approach and participatory local development planning, by Elizabeth M. Gonzales. Group-building, production success and the struggle to prevent capture of the resource, by B.K. Sahay, K.P. Singh and S.N. Pandeya. Urban agriculture, water reuse and local economies: case study of coastal riverine Settlements of Ondo State, Nigeria, by Yemi Akegbejo-Samsons. Livelihoods analysis: actual experience from using PRA, by Pham Minh Tam and Trinh Quang Tu. A sustainable livelihoods approach to fisheries development for poverty alleviation in southeastern Vietnam, by Nguyen Van Tu and Nguyen Minh Duc
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[ES]El presente artículo analiza la evolución del premio de la plata durante el siglo XVII en Guipúzcoa, donde aparecen dos modelos de comportamiento, siempre en relación con la abundancia y movimiento de la plata, que es el principal factor que explica las variaciones del premio. Se constata, no obstante, que en cada localidad los premios son diferentes, lo que demuestra cierta autonomía de las economías locales de Antiguo Régimen. Así mismo, hay que decir que las mayores repercusiones de este fenómeno se dejaron sentir en los mercados y en las transacciones locales, afectando principalmente a los consumidores. De todas formas, se demuestra la necesidad de seguir realizando investigaciones en los diferentes territorios que formaban la Corona, y desterrar definitivamente la generalización de datos como los de Hamilton.
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The principal objective of this study is to evaluate the benefits that accrue to the national economies as a result of different longline operational models and licensing regimes, computed, for comparability reasons, on a per tonne basis. The primary source for the derivation of these per tonne returns was individual fisheries enterprises currently operating in the sector in the countries chosen for this study. In each case, the company disclosed to the consultant detailed financial, operational and marketing data which has enabled the findings to be based upon actual empirical data, rather than assumptions or interpretations of current practice and benefit outcomes. Data obtained related principally to the 2005 calendar year. [36pp.]
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This report was prepared for and funded by the Florida State Department of Environmental Protection with the encouragement of members from the Florida Ocean Alliance, Florida Oceans and Coastal Resources Council and other groups with deep interests in the future of Florida’s coast. It is a preliminary study of Florida’s Ocean and Coastal Economies based only on information currently found within the datasets of the National Ocean Economics Program. (NOEP). It reflects only a portion of the value of Florida’s coastal related economy and should not be considered comprehensive. A more customized study based on the unique coastal and ocean-dependent economic activities of the State of Florida should be carried out to complete the picture of Florida’s dependence upon its coasts. (PDF has 129 pages.)
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Executive Summary: For over three decades, scientists have been documenting the decline of coral reef ecosystems, amid increasing recognition of their value in supporting high biological diversity and their many benefits to human society. Coral reef ecosystems are recognized for their benefits on many levels, such as supporting economies by nurturing fisheries and providing for recreational and tourism opportunities, providing substances useful for medical purposes, performing essential ecosystem services that protect against coastal erosion, and provid-ing a diversity of other, more intangible contributions to many cultures. In the past decade, the increased awareness regarding coral reefs has prompted action by governmental and non-governmental organizations, including increased funding from the U.S. Congress for conservation of these important ecosystems and creation of the U.S. Coral Reef Task Force (USCRTF) to coordinate activities and implement conservation measures [Presidential Executive Order 13089]. Numerous partnerships forged among Federal agencies and state, local, non-governmental, academic and private partners support activities that range from basic science to systematic monitoring of ecosystem com-ponents and are conducted by government agencies, non-governmental organizations, universities, and the private sector. This report shares the results of many of these efforts in the framework of a broad assessment of the condition of coral reef ecosystems across 14 U.S. jurisdictions and Pacific Freely Associated States. This report relies heavily on quantitative, spatially-explicit data that has been collected in the recent past and comparisons with historical data, where possible. The success of this effort can be attributed to the dedication of over 160 report contributors who comprised the expert writing teams for each jurisdiction. The content of the report chapters are the result of their considerable collaborative efforts. The writing teams, which were organized by jurisdiction and comprised of experts from numerous research and management institutions, were provided a basic chapter outline and a length limit, but the content of each chapter was left entirely to their discretion. Each jurisdictional chapter in the report is structured to: 1) describe how each of the primary threats identified in the National Coral Reef Action Strategy (NCRAS) has manifested in the jurisdiction; 2) introduce ongoing monitoring and assessment activities relative to three major categories of inquiry – water quality, benthic habitats, and associated biological communities – and provide summary results in a data-rich format; and 3) highlight recent management activities that promote conservation of coral reef ecosystems.
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Executive Summary: The marine environment plays a critical role in the amount of carbon dioxide (CO2) that remains within Earth’s atmosphere, but has not received as much attention as the terrestrial environment when it comes to climate change discussions, programs, and plans for action. It is now apparent that the oceans have begun to reach a state of CO2 saturation, no longer maintaining the “steady-state” carbon cycle that existed prior to the Industrial Revolution. The increasing amount of CO2 present within the oceans and the atmosphere has an effect on climate and a cascading effect on the marine environment. Potential physical effects of climate change within the marine environment, including ocean acidification, changes in wind and upwelling regimes, increasing global sea surface temperatures, and sea level rise, can lead to dramatic, fundamental changes within marine and coastal ecosystems. Altered ecosystems can result in changing coastal economies through a reduction in marine ecosystem services such as commercial fish stocks and coastal tourism. Local impacts from climate change should be a front line issue for natural resource managers, but they often feel too overwhelmed by the magnitude of this issue to begin to take action. They may not feel they have the time, funding, or staff to take on a challenge as large as climate change and continue to not act as a result. Already, natural resource managers work to balance the needs of humans and the economy with ecosystem biodiversity and resilience. Responsible decisions are made each day that consider a wide variety of stakeholders, including community members, agencies, non-profit organizations, and business/industry. The issue of climate change must be approached as a collaborative effort, one that natural resource managers can facilitate by balancing human demands with healthy ecosystem function through research and monitoring, education and outreach, and policy reform. The Scientific Expert Group on Climate Change in their 2007 report titled, “Confronting Climate Change: Avoiding the Unmanageable and Managing the Unavoidable” charged governments around the world with developing strategies to “adapt to ongoing and future changes in climate change by integrating the implications of climate change into resource management and infrastructure development”. Resource managers must make future management decisions within an uncertain and changing climate based on both physical and biological ecosystem response to climate change and human perception of and response to the issue. Climate change is the biggest threat facing any protected area today and resource managers must lead the charge in addressing this threat. (PDF has 59 pages.)
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Analisa-se que os mercados não existiriam sem instituições, que as economias se organizaram segundo várias modalidades de governação, originando contextos institucionais relevantes para a interpretação dos contextos econômicos das nações. A partir dessa premissa, desenvolve-se a suposição de que há três domínios principais que formam a base organizacional em que assentam as dinâmicas positivas do capitalismo – as relações industriais, os processos de inclusão pelo trabalho e pela aprendizagem e as instituições. Por fim, pode-se concluir que as instituições da esfera legislativa, especialmente as vinculadas ao desenvolvimento e à democracia, constituem elementos essenciais para a organização qualificada da economia, influenciando as capacidades gerais de uma sociedade.