884 resultados para Recreation and state


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On July 12-15, 2008, researchers and resource managers met in Jupiter, Florida to discuss and review the state of knowledge regarding mesophotic coral ecosystems, develop a working definition for these ecosystems, identify critical resource management information needs, and develop a Mesophotic Coral Ecosystems Research Strategy to assist the U.S. National Oceanic and Atmospheric Administration (NOAA) and other agencies and institutions in their research prioritization and strategic planning for mesophotic coral ecosystems. Workshop participants included representatives from international, Federal, and state governments; academia; and nongovernmental organizations. The Mesophotic Coral Ecosystems Workshop was hosted by the Perry Institute for Marine Science (PIMS) and organized by NOAA and the U.S. Geological Survey (USGS). The workshop goals, objectives, schedule, and products were governed by a Steering Committee consisting of members from NOAA (National Centers for Coastal Ocean Science’s Center for Sponsored Coastal Ocean Research, the Office of Ocean Exploration and Research’s NOAA Undersea Research Program, and the National Marine Fisheries Service), USGS, PIMS, the Caribbean Coral Reef Institute, and the Bishop Museum.

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The dusky rockfish (Sebastes ciliatus) of the North Pacific Ocean has been considered a single variable species with light and dark forms distributed in deep and shallow water, respectively. These forms have been subjected to two distinct fisheries separately managed by federal and state agencies: the light deep form is captured in the offshore trawl fishery; the dark shallow form, in the nearshore jig fishery. The forms have been commonly recognized as the light dusky and dark dusky rockfishes. From morphological evidence correlated with color differences in some 400 specimens, we recognize two species corresponding with these color forms. Sebastes ciliatus (Tilesius) is the dark shallow-water species found in depths of 5−160 m in the western Aleutian Islands and eastern Bering Sea to British Columbia. The name Sebastes variabilis (Pallas) is resurrected from the synonymy of S. ciliatus to apply to the deeper water species known from depths of 12−675 m and ranging from Hokkaido, Japan, through the Aleutian Islands and eastern Bering Sea, to Oregon. Sebastes ciliatus is uniformly dark blue to black, gradually lightening on the ventrum, with a jet black peritoneum, a smaller symphyseal knob, and fewer lateral-line pores compared to S. variabilis. Sebastes variabilis is more variable in body color, ranging from light yellow to a more usual tan or greenish brown to a nearly uniform dark dorsum, but it invariably has a distinct red to white ventrum. Synonymies, diagnoses, descriptions, and geographic distributions are provided for each species.

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Lake victoria is the second largest lake in the world.the lake is shatred between three East African countries (Kenya,Uganda and Tanzania) the lake basin is estimatedto have about 30 million people who depend on it as a source of fish for food,employment,income and recreation.the lake is transport locally and regionally is used for recreation and is recongnised internationally for its high fish species diversity of ecological and scientific value. This document in the first in a series to be produced on different fish production systems in Uganda and should stimulate discussions and comments to guide application of scientific findings into the policy environment.

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This article presents a novel algorithm for learning parameters in statistical dialogue systems which are modeled as Partially Observable Markov Decision Processes (POMDPs). The three main components of a POMDP dialogue manager are a dialogue model representing dialogue state information; a policy that selects the system's responses based on the inferred state; and a reward function that specifies the desired behavior of the system. Ideally both the model parameters and the policy would be designed to maximize the cumulative reward. However, while there are many techniques available for learning the optimal policy, no good ways of learning the optimal model parameters that scale to real-world dialogue systems have been found yet. The presented algorithm, called the Natural Actor and Belief Critic (NABC), is a policy gradient method that offers a solution to this problem. Based on observed rewards, the algorithm estimates the natural gradient of the expected cumulative reward. The resulting gradient is then used to adapt both the prior distribution of the dialogue model parameters and the policy parameters. In addition, the article presents a variant of the NABC algorithm, called the Natural Belief Critic (NBC), which assumes that the policy is fixed and only the model parameters need to be estimated. The algorithms are evaluated on a spoken dialogue system in the tourist information domain. The experiments show that model parameters estimated to maximize the expected cumulative reward result in significantly improved performance compared to the baseline hand-crafted model parameters. The algorithms are also compared to optimization techniques using plain gradients and state-of-the-art random search algorithms. In all cases, the algorithms based on the natural gradient work significantly better. © 2011 ACM.

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Water supply and wastewater control are critical elements of society's infrastructure. The objective of this study will be to provide a generic risk assessment tool to provide municipalities and the nation as a whole with a quantifiable assessment of their vulnerability to water infrastructure threats. The approach will prioritize countermeasures and identify where research and development is required to further minimize risk. This paper outlines the current context, primary concerns and state-of-the art in critical infrastructure risk management for the water sector and proposes a novel approach to resolve existing questions in the field. The proposed approach is based on a modular framework that derives a quantitative risk index for varied domains of interest. The approach methodology is scaleable and based on formal definitions of event probability and severity. The framework is equally applicable to natural and human-induced hazard types and can be used for analysis of compound risk events.

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Breather stability and longevity in thermally relaxing nonlinear arrays is investigated under the scrutiny of the analysis and tools employed for time series and state reconstruction of a dynamical system. We briefly review the methods used in the analysis and characterize a breather in terms of the results obtained with such methods. Our present work focuses on spontaneously appearing breathers in thermal Fermi-Pasta-Ulam arrays but we believe that the conclusions are general enough to describe many other related situations; the particular case described in detail is presented as another example of systems where three incommensurable frequencies dominate their chaotic dynamics (reminiscent of the Ruelle-Takens scenario for the appearance of chaotic behavior in nonlinear systems). This characterization may also be of great help for the discovery of breathers in experimental situations where the temporal evolution of a local variable (like the site energy) is the only available/measured data. © 2005 American Institute of Physics.

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Gymnocypris przewalskii (Kessler 1876) is an endangered and state-protected rare fish species in Qinghai Lake, China. To further understand the life history and distribution of this fish, five surveys were carried out in Qinghai Lake between 2002-2006. Results of these surveys indicate that fishes were predominantly distributed about 2 m under the surface. In July, significant differences in fish density were found between surface and bottom layers (P = 0.001), and/or between middle and bottom layers (P = 0.025). Fish density was the greatest in the surface layer. In August and October, no significant differences were found between the different layers, but the bottom layer had a greater fish density. Furthermore, there were very large differences among different zones in fish distribution density. Differences in horizontal distribution were not significantly correlated to factors such as water depth and inshore distance, possibly because of very low and uniform fish density. Feeding, changes in water temperature, over-wintering and spawning appeared to influence fish distribution. Hydroacoustic estimates of G. przewalskii biomass in Qinghai Lake increased significantly between 2002 and 2006. We attribute this increase to the management measures put in place to protect this species.

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Stannic oxide xerogel was prepared by a forced hydrolysis method using SnCl4 as the precursor. The average grain sizes of the nanosized stannic oxide powders varied with the sintering temperatures. The powders were characterized by several different physico-chemical techniques. TEM was employed for the direct observation on grain sizes, shape and state of aggregation of the particles. XRD technique was used for the determination of the crystalline structure. Microstructural parameters of average crystallite size () and mean-square root microstrain (epsilon(2)>(1/2)) for the samples were calculated from the broadened values of the half-peak intensity of XRD. The atomic ratio between oxygen and tin in the surface region of the particles was estimated through the analysis of XPS. Attributing to lots of oxygen vacancies in the surface region of the nanoparticulates and the 'trapped electrons' in the vacancies, an ESR signal was observed in the sample sintered at 300 degrees C for 2 h. FTIR of the powders showed that intensity of the transverse optical mode of Sn-O stretching vibration increased with the sintering temperature while the bending vibration of O-Sn-O showed a blue shift. For Raman spectra, very important spectral characteristics such as variations of intensity and width of the bands were observed. A new Raman vibrational band located at 572 cm(-1) was identified in the samples of nanosized stannic oxide powders. Variation of these spectroscopic properties were strongly affected by grain size, shape and state of aggregation of the nanosized particulates.

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We describe the automatic synthesis of a global nonlinear controller for stabilizing a magnetic levitation system. The synthesized control system can stabilize the maglev vehicle with large initial displacements from an equilibrium, and possesses a much larger operating region than the classical linear feedback design for the same system. The controller is automatically synthesized by a suite of computational tools. This work demonstrates that the difficult control synthesis task can be automated, using programs that actively exploit knowledge of nonlinear dynamics and state space and combine powerful numerical and symbolic computations with spatial-reasoning techniques.

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We revisit the problem of connection management for reliable transport. At one extreme, a pure soft-state (SS) approach (as in Delta-t [9]) safely removes the state of a connection at the sender and receiver once the state timers expire without the need for explicit removal messages. And new connections are established without an explicit handshaking phase. On the other hand, a hybrid hard-state/soft-state (HS+SS) approach (as in TCP) uses both explicit handshaking as well as timer-based management of the connection’s state. In this paper, we consider the worst-case scenario of reliable single-message communication, and develop a common analytical model that can be instantiated to capture either the SS approach or the HS+SS approach. We compare the two approaches in terms of goodput, message and state overhead. We also use simulations to compare against other approaches, and evaluate them in terms of correctness (with respect to data loss and duplication) and robustness to bad network conditions (high message loss rate and variable channel delays). Our results show that the SS approach is more robust, and has lower message overhead. On the other hand, SS requires more memory to keep connection states, which reduces goodput. Given memories are getting bigger and cheaper, SS presents the best choice over bandwidth-constrained, error-prone networks.

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My thesis presents an examination of Ce que c'est que la France toute Catholique (1686) by Pierre Bayle, a prominent figure in the Republic of Letters and the Huguenot Refuge in the seventeenth century. This pamphlet was the first occasional text that Bayle published following the Revocation of the Edict of Nantes in which the religious toleration afforded to the Huguenot minority in France was repealed, a pivotal moment in the history of early modern France. In my thesis, I analyse the specific context within which Bayle wrote this pamphlet as a means of addressing a number of issues, including the legitimacy of forced conversions, the impact of the religious controversy upon exchanges in the Republic of Letters, the nature of religious zeal and finally the alliance of Church and state discourses in the early modern period. An examination of this context provides a basis from which to re-interpret the rhetorical strategies at work within the pamphlet, and also to come to an increased understanding of how, why and to what end he wrote it. In turn this allowed me to examine the relationship between this often overlooked pamphlet and the more extensively studied Commentaire Philosophique, in which Bayle argued in favour of religious toleration. Ultimately, understanding the relationship between these two texts proves essential in order to characterise his response to the Revocation of the Edict of Nantes and to understand the place of the pamphlet within his oeuvre. Furthermore, an analysis of the pamphlet and the Commentaire Philosophique provide a lens through which to elucidate both Bayle's intellectual development at this early stage in his career, and also the wider context of the rise of toleration theory and the evolution of modes of civility within the Republic of Letters on the eve of the Enlightenment.

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This PhD thesis investigates the potential use of science communication models to engage a broader swathe of actors in decision making in relation to scientific and technological innovation in order to address possible democratic deficits in science and technology policy-making. A four-pronged research approach has been employed to examine different representations of the public(s) and different modes of engagement. The first case study investigates whether patient-groups could represent an alternative needs-driven approach to biomedical and health sciences R & D. This is followed by enquiry into the potential for Science Shops to represent a bottom-up approach to promote research and development of local relevance. The barriers and opportunities for the involvement of scientific researchers in science communication are next investigated via a national survey which is comparable to a similar survey conducted in the UK. The final case study investigates to what extent opposition or support regarding nanotechnology (as an emerging technology) is reflected amongst the YouTube user community and the findings are considered in the context of how support or opposition to new or emerging technologies can be addressed using conflict resolution based approaches to manage potential conflict trajectories. The research indicates that the majority of communication exercises of relevance to science policy and planning take the form of a one-way flow of information with little or no facility for public feedback. This thesis proposes that a more bottom-up approach to research and technology would help broaden acceptability and accountability for decisions made relating to new or existing technological trajectories. This approach could be better integrated with and complementary to government, institutional, e.g. university, and research funding agencies activities and help ensure that public needs and issues are better addressed directly by the research community. Such approaches could also facilitate empowerment of societal stakeholders regarding scientific literacy and agenda-setting. One-way information relays could be adapted to facilitate feedback from representative groups e.g. Non-governmental organisations or Civil Society Organisations (such as patient groups) in order to enhance the functioning and socio-economic relevance of knowledge-based societies to the betterment of human livelihoods.

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The health of a nation tells much about the nature of a social contract between citizen and state. The way that health care is organised, and the degree to which it is equitably accessible, constitutes a manifestation of the effects of moments and events in that country's history. Using four case studies, this thesis uses a historical genealogical approach to explain the evolution of Ireland's particular version of health care provision. The total social fact of the gift relationship, central to all human relations, will be used to form a theoretical and conceptual framework on which to build an analysis of Ireland's health and welfare conditions. Additionally, social contract theory will enable an examination of the role of solidarity in relation to social expectations around health care provision. Through the analysis of these cases, the complex matrix of the influential forces that have shaped current conditions are exposed and revealed, enabling a critical understanding of the extent of acquiescence to the inequitable system that arguably exists. The vulnerability of citizens in need of care to the external and global effects of market forces and neoliberalism, therefore, becomes central to any argument for state-provided health and welfare. The hegemony of such forces can be seen to influence the manner in which the idea of individual self-reliance, in place of collective solidarity, is conceptualised and subsequently infiltrated into a range of aspects of the social world. For example, the particular discourse of the market and of economic concerns succeeds in shaping understandings of responsibilities around central areas of health and welfare. Similarly the 'possessor principle' can be seen to be misplaced within the context of health and social care, but yet has become normalised within this discourse. Within this matrix of complex influencing factors, the welfare state struggles to impose a balance between market values and social values. Responsibilities of the state to support and compensate its citizens for the ills of the market have become devalued, as the core values of classical liberalism have become distorted beyond recognition, leaving instead bare neoliberal concerns. This thesis traces the genealogical origins of this transition within the recent history of Irish health care and thereby reveals the embedding of individualism in place of solidarity, the on going reneging of the social contract and the corruption of the gift relationship.

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For centuries Cork’s Shawlies, working-class women, survived by trading on public streets. My study explores how the first Irish Free State government, and Cork’s local authority, limited the rights of poor women to earn by subsistence trading with The Street Trading Act, 1926. The government insisted this would regulate street trading. In practice it further marginalised the women economically and socially, containing them outside the privileged, commercial city centre. In Cork the legislation facilitated the gradual disappearance of the Shawlies amid entrenched social processes and relations, contingencies that allowed for the abuse of their rights in the service of amalgamated business interests. This study address the role of discourses in deepening this marginalisation. My theoretical framework is designed to demonstrate how a seemingly innocuous piece of legislation would, in practice, do this. I set out the concepts of ‘Thriving State’, ‘Prosperous State’, and state of ‘Best Intentions’ that uses gentrification to meet these goals. The existing knowledge on women in trade is then examined, highlighting the gaps in what is known about the Shawlies. Chapter 3 details the theory behind my genealogical method. The legislation, debate, and other data produced at the national level is then examined, before moving to the local data. Chapter 6 is devoted to the Shawlies, setting their stories in the larger context of the debates. An examination of studies of contemporary women street traders in poor nations follows, along with a brief history of the decline of street trading in New York city under gentrification. Points of convergence between that process and the one in Cork are identified, along with convergences between contemporary traders and the Shawlies. The conclusion sets out my methodological, theoretical and substantive discoveries, and comments on current nostalgic renderings of the Shawlies in Cork’s newly gentrified Corn Market Street.

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Smoking is an expensive habit. Smoking households spend, on average, more than $US1000 annually on cigarettes. When a family member quits, in addition to the former smoker's improved long-term health, families benefit because savings from reduced cigarette expenditures can be allocated to other goods. For households in which some members continue to smoke, smoking expenditures crowd-out other purchases, which may affect other household members, as well as the smoker. We empirically analyse how expenditures on tobacco crowd-out consumption of other goods, estimating the patterns of substitution and complementarity between tobacco products and other categories of household expenditure. We use the Consumer Expenditure Survey data for the years 1995-2001, which we complement with regional price data and state cigarette prices. We estimate a consumer demand system that includes several main expenditure categories (cigarettes, food, alcohol, housing, apparel, transportation, medical care) and controls for socioeconomic variables and other sources of observable heterogeneity. Descriptive data indicate that, comparing smokers to nonsmokers, smokers spend less on housing. Results from the demand system indicate that as the price of cigarettes rises, households increase the quantity of food purchased, and, in some samples, reduce the quantity of apparel and housing purchased.