120 research outputs found

    Quantify the monthly to decadal variability of climate effects on the lower trophic levelse of shelf sea ecosystems

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    ECOOP WP10, Deliverable no: D10.1.2.1This report describes three studies using multi-decadal simulations of regional coupled hydrodynamics ecosystem models. These models are used to investigate the relationship between lower trophic level marine ecosystems and biogeochemistry, and the physical environment. The models considered here: POLCOMS-ERSEM Atlantic Margin Model run from 1960 to 2003 (NERC and PML) NORWECOM North Sea Model run from 1985-2006 (IMR) ECOSMO (UiB-GFI) North sea and Baltic Sea run 1980-2004 (UiB-GFI) The POLCOMS-ERSEM model is validated using in-situ data from the world ocean data centre and analysed to investigate the potential long term changes in primary production across the period 1960-2004, in the context of model open boundary conditions and drift. The model experiments demonstrate a strong sensitivity of the on-shelf primary production to the oceanic nutrient boundary conditions, suggesting cross-shelf edge nutrient fluxes provide a significant source of variability. The relationship between the model results and the North Atlantic Oscillation are also considered, demonstrating a r~0.65 correlation with on-shelf nutrients and the NAO The NORWECOM model is validated here using time series data from the Dutch coast. Correlations between model variables in a selection of ICES boxes are compared with a number of driving factors. River loads are shown to dominate coastal boxes. The relationships in open-shelf boxes are more ambiguous, although the southerly inflow is demonstrated to have an important role. The validation of the POLCOMS-ERSEM and NORWECOM models both conclude that the simulations have better skill for nutrients than chlorophyll and in open-shelf seas away from the coast. The validation of ECOSMO presented here focuses on zooplankton and comparison with data from the continuous plankton recorder, investigating six different approaches to matching CPR records with model data. Across the North Sea the mean annual cycle shows good agreement between model and CPR. There is also good correlation with along-track variability. EOF and correlation analysis is used to relate the primary production in the North Sea to atmospheric forcing parameters. The EOF patterns tend to match the distribution of summer time stratification, while the wind speed is shows the highest correlation, particularly during the onset and breakdown of stratification. This indicates the strength of cross-thermocline mixing is an important control on primary production variability. The ECOSMO model has been further developed for use in the Baltic by inclusion of nitrogen fixing cyanobacteria. These studies each demonstrate significant control of the inter-annual variability of shelf sea ecosystems through a range of external forcing vectors: oceanic through cross-shelf edge nutrient flux, terrestrial through variations in river nutrient loading, and atmospheric via the wind control of vertical mixing. Each of these vectors potentially mediates climatic variability and climate change

    Knowledge status and gaps for the North Sea – focusing on discharges.

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    The Norwegian government will develop a management plan for the Norwegian sector of the North Sea. Mapping of the data requirement related to the interaction between land, coast and ocean and identification of specially vulnerable and valuable areas are included. The project focuses on discharges and their impact on the environment in the Norwegian part of the North Sea (part of OSPAR’s Region II, Greater North Sea), however information from other countries and regions within the North Sea is also included. OSPAR is developing a Quality Status Report for the North Sea area entitled the QSR 2010. QSR 2010 is based on regional assessments while this report is a pilot project aiming to identify additional data required for an upcoming management plan for the North Sea. OSPAR QSR 2010 will develop an assessment for the North Sea, however this will probably not be area specific enough to fulfil the needs for a management plan. In addition to the QSR 2010 there will be a need to develop regional plans based on collaboration between the NS countries. EUs directives, conventions and agencies supply a network of laws, directives and agreements relevant for a future management plan for the North Sea. Relevant sources of data and overall estimates of the amounts of nutrients and pollutants discharged from Norwegian sources into the North Sea are presented. An assessment of the knowledge status is given for individual sectors, with a particular focus on areas where present knowledge or data availability is considered insufficient. Effects of discharges on vulnerable and valuable areas are discussed in the context available data from monitoring and future needs to fill the gaps

    Object-oriented data modeling

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    The object-oriented paradigm models local behavior, and to a lesser extent, the structure of a problem. Semantic data models describe structure and semantics. This thesis unifies the behavioral focus of the object-oriented paradigm with the structural and semantic focus of semantic data models. The approach contains expressive abstractions to model static and derived data, semantics, and behavior. The abstractions keep the data model closer to the problem domain, and can be translated into a relational (or other) implementation. The paper makes six contributions. First, a comprehensive set of data structuring abstractions are described. Second, the abstractions are compared to the entity-relationship and relational models. Third, semantic information inherent in the functional representation of the abstractions is identified. Fourth, a set of behavioral abstractions are described. Fifth, an algorithm that describes the dynamics between mathematically derived attributes of cooperating objects is presented. Sixth, weaknesses of object-oriented programming languages are identified

    An object addressing mechanism for statically typed languages with multiple inheritance

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    In this paper we are concerned with addressing techniques for statically typed languages with multiple inheritance. The addressing techniques are responsible for the efficient implementation of record field selection. In object-oriented languages, this record selection is equivalent to the access of methods. Thus, the efficiency of these techniques greatly affects the overall performance of an object-oriented language. We will demonstrate that addresses, in such systems, cannot always be calculated statically and show how symbol tables have been used as address maps at run time. The essence of the paper is a new addressing technique that can statically calculate either the address of a field or the address of the address of the field. This technique is powerful enough to support an efficient implementation of multiple inheritance with implicit subtyping as described by Cardelli.Othe

    Classbox/J: Controlling the Scope of Change in Java

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    International audienceUnanticipated changes to complex software systems can introduce anomalies such as duplicated code, suboptimal inheritance rela- tionships and a proliferation of run-time downcasts. Refactoring to eliminate these anomalies may not be an option, at least in certain stages of software evolution. Classboxes are modules that restrict the visibility of changes to selected clients only, thereby offering more freedom in the way unanticipated changes may be imple- mented, and thus reducing the need for convoluted design anoma- lies. In this paper we demonstrate how classboxes can be imple- mented in statically-typed languages like Java. We also present an extended case study of Swing, a Java GUI package built on top of AWT, and we document the ensuing anomalies that Swing intro- duces. We show how Classbox/J, a prototype implementation of classboxes for Java, is used to provide a cleaner implementation of Swing using local refinement rather than subclassing

    The Larch/Smalltalk Interface Specification Language

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    Object-oriented programming languages, such as Smalltalk, help one to build reusable program modules. The reuse of program modules requires adequate documentation --- formal or informal. Larch/Smalltalk is a formal specification language for specifying such reusable Smalltalk modules. Larch/Smalltalk firmly separates specification from implementation. In Larch/Smalltalk, the unit of specification is an abstract data type, which is an abstraction of the behavior produced by one or more Smalltalk classes. A type can be a subtype of other types, which allows types to be organized based on specified behavior, and also allows for inheritance of their specifications. Larch/Smalltalk specifications are developed using specification tools integrated in the Smalltalk programming environment

    Innovation for Sustainability and Networking

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    Throughout human history, innovation has been the main factor in adapting humanity to its settings. On the basis of earlier practice, human creativity allows the finding of new, permanent ways to do things. their applications encourage new spaces, new necessities and new lifestyles. Innovation has been an element of human capacities from its earlier stages, but it has been recognized only recently as a clear device of social and economic change

    Innovation for sustainability and networking

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    The current work sought to understand the softer dimensions which constitute the building blocks of innovation networks. In particular, it addressed the individual and social aspects that bond organizations in such networks. Based on interview data collected from 45 entities involved in various innovation networks in three regions in Portugal, the findings revealed that there are three key dimensions at the micro level of analysis which contribute to understand how organization networks emerge and develop. These dimensions constitute the main theoretical contributions of the current research to the emerging field of innovation networks.info:eu-repo/semantics/publishedVersio

    Early aspects: aspect-oriented requirements engineering and architecture design

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    This paper reports on the third Early Aspects: Aspect-Oriented Requirements Engineering and Architecture Design Workshop, which has been held in Lancaster, UK, on March 21, 2004. The workshop included a presentation session and working sessions in which the particular topics on early aspects were discussed. The primary goal of the workshop was to focus on challenges to defining methodical software development processes for aspects from early on in the software life cycle and explore the potential of proposed methods and techniques to scale up to industrial applications

    Introduction to the Literature on Semantics

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    An introduction to the literature on semantics. Included are pointers to the literature on axiomatic semantics, denotational semantics, operational semantics, and type theory
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