2,398 research outputs found

    Valuing Ecosystem Services with Fishery Rents: A Lumped-Parameter Approach to Hypoxia in the Neuse River Estuary

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    Valuing ecosystem services with microeconomic underpinnings presents challenges because these services typically constitute nonmarket values and contribute to human welfare indirectly through a series of ecological pathways that are dynamic, nonlinear, and difficult to quantify and link to appropriate economic spatial and temporal scales. This paper develops and demonstrates a method to value a portion of ecosystem services when a commercial fishery is dependent on the quality of estuarine habitat. Using a lumped-parameter, dynamic open access bioeconomic model that is spatially explicit and includes predator-prey interactions, this paper quantifies part of the value of improved ecosystem function in the Neuse River Estuary when nutrient pollution is reduced. Specifically, it traces the effects of nitrogen loading on the North Carolina commercial blue crab fishery by modeling the response of primary production and the subsequent impact on hypoxia (low dissolved oxygen). Hypoxia, in turn, affects blue crabs and their preferred prey. The discounted present value fishery rent increase from a 30% reduction in nitrogen loadings in the Neuse is $2.56 million, though this welfare estimate is fairly sensitive to some parameter values. Surprisingly, this number is not sensitive to initial conditions.Open access, Predator-prey, Hypoxia, Habitat-dependent fisheries

    Towards an integrated model for citizen adoption of E-government services in developing countries: A Saudi Arabia case study

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    This paper considers the challenges that face the widespread adoption of E-government in developing countries, using Saudi Arabian our case study. E-government can be defined based on an existing set of requirements. In this paper we define E-government as a matrix of stakeholders; governments to governments, governments to business and governments to citizens using information and communications technology to deliver and consume services. E-government has been implemented for a considerable time in developed countries. However E-government services still faces many challenges their implemented and general adoption in developing countries. Therefore, this paper presents an integrated model for ascertaining the intention to adopt E-government services and thereby aid governments in accessing what is required to increase adoption

    Expert Finding by Capturing Organisational Knowledge from Legacy Documents

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    Organisations capitalise on their best knowledge through the improvement of shared expertise which leads to a higher level of productivity and competency. The recognition of the need to foster the sharing of expertise has led to the development of expert finder systems that hold pointers to experts who posses specific knowledge in organisations. This paper discusses an approach to locating an expert through the application of information retrieval and analysis processes to an organization’s existing information resources, with specific reference to the engineering design domain. The approach taken was realised through an expert finder system framework. It enables the relationships of heterogeneous information sources with experts to be factored in modelling individuals’ expertise. These valuable relationships are typically ignored by existing expert finder systems, which only focus on how documents relate to their content. The developed framework also provides an architecture that can be easily adapted to different organisational environments. In addition, it also allows users to access the expertise recognition logic, giving them greater trust in the systems implemented using this framework. The framework were applied to real world application and evaluated within a major engineering company

    On a Service-Oriented Approach for an Engineering Knowledge Desktop

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    Increasingly, manufacturing companies are shifting their focus from selling products to providing services. As a result, when designing new products, engineers must increasingly consider the life cycle costs in addition to any design requirements. To identify possible areas of concern, designers are required to consult existing maintenance information from identical products. However, in a large engineering company, the amount of information available is significant and in wide range of formats. This paper presents a prototype knowledge desktop suitable for the design engineer. The Engineering Knowledge Desktop analyses and suggests relevant information from ontologically marked-up heterogeneous web resources. It is designed using a Service-Oriented Architecture, with an ontology to mediate between Web Services. It has been delivered to the user community for evaluation

    Transparent authentication methodology in electronic education

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    In the context of on-line assessment in e-learning, a problem arises when a student taking an exam may wish to cheat by handing over personal credentials to someone else to take their place in an exam, Another problem is that there is no method for signing digital content as it is being produced in a computerized environment. Our proposed solution is to digitally sign the participant’s work by embedding voice samples in the transcript paper at regular intervals. In this investigation, we have demonstrated that a transparent stenographic methodology will provide an innovative and practical solution for achieving continuous authentication in an online educational environment by successful insertion and extraction of audio digital signatures

    The Silver Anniversary of the United States’ Exclusive Economic Zone: Twenty-Five Years of Ocean Use and Abuse, and the Possibility of a Blue Water Public Trust Doctrine

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    Sustainably managing marine ecosystems has proved nearly impossible, with few success stories. Ecosystem management failures largely stem from the traditional sector-by-sector, issue-by-issue approach to managing ocean-borne activities—an approach that is fundamentally unable to keep pace with the dynamics of coupled human, ecologi cal and oceanographic systems. In the United States today there are over twenty federal agencies and thirty-five coastal states and territories operating under dozens of statutory authorities shaping coastal and ocean policy. Among marine ecologists and policy experts there is an emerging consensus that a major overhaul in U.S. ocean governance is necessary. This Article suggests that the public trust doctrine—an ancient legal concept that is already incorporated in U.S. state coastal laws—can uniquely provide a unifying concept for U.S. federal ocean governance. Though the public trust concept can be located in the legal systems of many countries, it robustly manifests in the United States, where it has historically protected the public’s rights to fishing, navigation, and commerce in and over navigable waterways and tidal waters. In its most basic form, the doctrine obliges governments to manage common natural resources, the body of the trust, in the best interest of their citizens, the beneficiaries of the trust. Today the public trust doctrin e is integral to the protection of coastal ecosystems and beach access in many states and has even made its way into state constitutions. It would be simple, and seemingly logical, to assume that the same fiduciary responsibility of states to protect public trust uses of their waters extends to all marine resources within the United States’ 200-mile Exclusive Economic Zone (EEZ). However an artificial line has been drawn around state waters, and the legal authority and responsibility of the U.S. government to protect public trust resources in the vast space of its EEZ (the largest of any country on earth) have never been fully and expressly established. Securing the place of the public trust doctrine in U.S. federal oceans management would be valuable, given the immense pressure to exploit EEZ resources, the failure of the current regulatory approach, improved scientific understanding of the interconnected nature of ocean ecosystems, and the growing demand for sustainable management of ocean resources. This Article will outline the development of states’ public trust doctrines; discuss the expansion of U.S. sovereignty over its neighboring ocean waters during the twentieth century; analyze possible avenues for expanding the doctrine to federal waters; and consider how a federal public trust doctrine could clarify some specific emerging issues in U.S. oceans management. At the heart of our analysis lie three questions: (1) does a federal public trust doctrine exist; (2) if so, can we rightfully extend it to include the entirety of the U.S. ocean waters; and (3) could the doctrine provide the missing catalyst for federal agencies to manage the use of U.S. ocean resources in a coordinated, sustainable fashion

    Towards a theology of story : an experiment in contextual theology

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    Bibliography: pages 261-275.This study examines the role of story in the Christian proclamation. It focusses upon the dynamic of story which unites praxis and language in a single message. There are four stages of argument. The First Part examines the hermeneutic problem especially as discussed in the work of Gadamer, Palmer, Robinson, Funk and others writers on the so-called New Hermeneutic. Their views are set against the perspective of liberation and contextual theologies from Cone, Segundo, and Miguez Bonino amongst others. The impact of social praxis and context on communication and interpretation is examined. Its importance as a barrier to the translation of the whole dynamic of the gospel proclamation is stressed. Part Two examines Jesus parables and acted parables. The data comes from two sources: the dominant form-critical approach to parables as exemplified by Jeremias or Crossan, in which the situation behind the text is examined. Second is the recent sociological approach to the practice of Jesus taken by such scholars as Theissen or Echegaray. The approach to this data comes from an analysis of the "history of the transmission of the tradition", a concept developed by Pannenberg from the work of Rentdorf and Von Rad. It provides a series of categories through which the data is examined. The dynamic of story is shown in the unity of actions. Function and structure in the parabolic stories and The Third Part surveys the role of story as a category in contemporary theology. First, the approach of narrative theology is cosidered as in the work of Stroup, McClendon, McFague and others. Then the role of story in Third World theological reflection on liberation struggles is described. Examples are drawn mainly from Asia (China, Korea and the Philippines). The Latin American debate about such cultural forms is briefly reviewed. Lastly the role of story in some British contextual theology is discussed. The dynamic of story is discovered in the function and impact of stories in theological reflection in the struggle against oppressive situations. Part Four briefly notes the perspective of critical theorists, like Habermas, on hermeneutics. Finally an attempt is made to tell stories of theological reflection on domination as a practical exercise illustrating the theoretical themes of the study. The impetus for the study arises from two periods of practical experience. One of some ten years duration, was work in British inner city ministry and theological training, in a context where community groups were struggling against many manifestations of urban stress. The second period, of about half a year, was an exposure to the conditions of life in rural (communal lands) and urban (high density residential area) Zimbabwe, as a visitor to the Methodist Church. In both instances stories were a vital means of communication about the most important things

    Data Mining to Support Engineering Design Decision

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    The design and maintenance of an aero-engine generates a significant amount of documentation. When designing new engines, engineers must obtain knowledge gained from maintenance of existing engines to identify possible areas of concern. Firstly, this paper investigate the use of advanced business intelligence tenchniques to solve the problem of knowledge transfer from maintenance to design of aeroengines. Based on data availability and quality, various models were deployed. An association model was used to uncover hidden trends among parts involved in maintenance events. Classification techniques comprising of various algorithms was employed to determine severity of events. Causes of high severity events that lead to major financial loss was traced with the help of summarization techniques. Secondly this paper compares and evaluates the business intelligence approach to solve the problem of knowledge transfer with solutions available from the Semantic Web. The results obtained provide a compelling need to have data mining support on RDF/OWL-based warehoused data

    Assessing Population Responses to Multiple Anthropogenic Effects: A Case Study with Brook Trout

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    Population declines are often caused by multiple factors, including anthropogenic ones that can be mitigated or reversed to enhance population recovery. We used a size-classified matrix population model to examine multiple anthropogenic effects on a population and determine which factors are most (or least) important to population dynamics. We modeled brook trout (Salvelinus fontinalis) in southern Appalachian mountain streams responding to multiple anthropogenic effects including the introduction of an exotic salmonid species (rainbow trout, Oncorhynchus mykiss), a decrease in pH (through acidic deposition), an increase in siltation (from roadbuilding and logging), and an increase in fishing pressure. Potential brook trout responses to rainbow trout include a decrease in survival rate of small fish, a change in density dependence in survival of small fish, and a decrease in growth rates of all sizes. When we included these responses in the population model, we found that population size tended to decrease with an increase in small-fish growth rate (producing a population with fewer, but larger, fish). In addition, changes in patterns of density-dependent survival also had a strong impact on both population size and size structure. Brook trout respond to decreases in pH with decreased growth rate in all size classes, decreased survival rates of small fish, and decreased egg-to-larva survival rates. This combination of effects, at magnitudes documented in laboratory experiments, had severe negative impacts on the modeled population. If siltation effects were severe, the extreme increase in egg-to-larva mortality could have strong negative effects on the population. However, even very strong increases in large fish mortality associated with sport harvesting were not likely to cause a local extinction. In all of these cases, the interaction of drastic changes in population size structure with randomly occurring floods or droughts may lead to even stronger negative impacts than those predicted from the deterministic model. Because these fish can reproduce at a small size, negative impacts on survival of the largest fish were not detrimental to the persistence of the population. Because survival of small juveniles is density dependent, even moderate decreases in survival in this stage had little effect on the ultimate population size. In general, a brook trout population will respond most negatively to factors that decrease survival of large juveniles and small adults, and growth rates of small juveniles.This work was supported by the Lucas Fellowship in Biomathematics at North Carolina State University (to E. A. Marschall), the J. F. Allen Award from the American Fisheries Society (to E. A. Marschall), an Electric Power Research Institute Fellowship in Population Dynamics (to E. A. Marschall), a U.S. Forest Service Cost-Share Agreement (to L.B. Crowder and E. A. Marschall), the Department of Zoology at North Carolina State University (to L. B. Crowder), and the Department of Zoology at The Ohio State University (to E. A. Marschall)

    Oat Grain Variety Trial at Overton for 2000-2001 and Three Year Means

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    Last updated: 6/12/200
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