3,439 research outputs found

    Great Expectations: The North American Commission on Environmental Cooperation Review of the Cozumel Pier Submission

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    Flame spread across liquid pools

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    For flame spread over liquid fuel pools, the existing literature suggests three gravitational influences: (1) liquid phase buoyant convection, delaying ignition and assisting flame spread; (2) hydrostatic pressure variation, due to variation in the liquid pool height caused by thermocapillary-induced convection; and (3) gas-phase buoyant convection in the opposite direction to the liquid phase motion. No current model accounts for all three influences. In fact, prior to this work, there was no ability to determine whether ignition delay times and flame spread rates would be greater or lesser in low gravity. Flame spread over liquid fuel pools is most commonly characterized by the relationship of the initial pool temperature to the fuel's idealized flash point temperature, with four or five separate characteristic regimes having been identified. In the uniform spread regime, control has been attributed to: (1) gas-phase conduction and radiation; (2) gas-phase conduction only; (3) gas-phase convection and liquid conduction, and most recently (4) liquid convection ahead of the flame. Suggestions were made that the liquid convection was owed to both vuoyancy and thermocapillarity. Of special interest to this work is the determination of whether, and under what conditions, pulsating spread can and will occur in microgravity in the absence of buoyant flows in both phases. The approach we have taken to resolving the importance of buoyancy for these flames is: (1) normal gravity experiments and advanced diagnostics; (2) microgravity experiments; and (3) numerical modelling at arbitrary gravitational level

    Evironmental Tax. Are Vehicle Registers in the EU Prepared?

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    The market system is unavailable to reflect negative externalities, caused by road motor trafic, in the realized prices. For that purpose, it would be appropriate to implement a general environmental road tax in the European Union member states. The question is whether the national registers of vehicles are prepared for such a change. Whether this is the case at present, may be found out by means of analyses of the available national registers. The next step is synthetic: the data must be subsequently completed on the basis of the knowledge of needs of currently existing systems of road motor vehicles taxation. In the end, the identified results may be supplemented with the known data published by international institutions. The results of the research show that the present systems of road motor vehicles taxation are utterly different and distortive. Only 12 countries of the European Union have registers which were clearly identified as prepared for the application of the environmental tax. Registers of the remaining countries do not contain one or more data that are necessary for the implementation of the environmental tax. For this reason we may assume that regardless of other determinants, environmental road tax shall not be introduced throughout the European Union in the foreseeable future.O

    Administrative Data in the IAB Metadata Management System

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    Presentation at the North American Data Documentation Conference (NADDI) 2013The Research Data Centre (FDZ) of the German Federal Employment Agency (BA) at the Institute for Employment Research (IAB) prepares and gives access to research data. Beside survey data the IAB provides data deriving from the administrative processes of the BA. This data is very complex and not easy to understand and use. Good data documentation is crucial for the users. DDI provides a data documentation standard that makes documentation and data sharing easier. The latter is especially important for providers of administrative data because more and more other data types are merged with administrative data. Nevertheless there are also some drawbacks when using the DDI standard. Data collection for administrative data differs from data collection for survey data but DDI was established for survey data. At the same time the description of complex administrative data should be simple as possible. IAB and TBA21 are currently carrying out a project to build a Metadata Management System for IAB. The presentation will highlight the documentation needs for administrative data and show how they are covered in the Management System. In addition the need for DDI profiles, comprehensive software tools and future proofed data documentation for multiple data sources will be depicted.Institute for Policy & Social Research, University of Kansas; University of Kansas Libraries; Alfred P. Sloan Foundation; Data Documentation Initiative Allianc

    Experiment plans to study preignition processes of a pool fire in low gravity

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    Science requirements are specified to guide experimental studies of transient heat transfer and fluid flow in an enclosure containing a two-layer gas-and-liquid system heated unevenly from above. Specifications are provided for experiments in three separate settings: (1) a normal gravity laboratory, (2) the NASA-LeRC Drop towers, and (3) a space-based laboratory (e.g., Shuttle, Space Station). A rationale is developed for both minimum and desired requirement levels. The principal objective of the experimental effort is to validate a computational model of the enclosed liquid fuel pool during the preignition phase and to determine via measurement the role of gravity on the behavior of the system. Preliminary results of single-phase normal gravity experiments and simulations are also presented

    Representing and Utilizing DDI in Relational Databases

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    This document is primarily intended for implementers of DDI-based metadata stores who are considering different technical options for housing and managing their metadata. The Data Documentation Initiative (DDI) metadata specification is expressed in the form of XML schema. With version 3, the DDI specification has become quite complex, including 21 namespaces and 846 elements. Organizations employing DDI, or considering doing so, may want to 1. store and manage the metadata elements in relational databases, for reasons of integration with existing systems, familiarity with the concepts of relational databases (such as Structured Query Language), systems performance, and/or other reasons; 2. select only the subset of the available DDI metadata elements that is of utility to their work, and have the flexibility of capturing metadata they need that would not fit into the DDI model. This paper discusses advantages and disadvantages of the relational database approach to managing DDI. It also describes methods for modeling DDI in relational databases and for formally defining subsets of DDI to employ in this environment.

    International Access to Administrative Data for Germany and Europe

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    In the last years access to research data has made a lot of progress in EU countries. Nevertheless transnational access to confidential microdata - although there are some developments like Data without Boundaries - is still complicated and needs improvement. The first part of the paper describes the (international) access to highly sensitive German administrative labour market data and how this international access is expanded within the research data centre in research data centre (RDC in RDC) approach. In the second part a broader view of international access to official microdata in the EU will be given. Starting with a brief overview of the EU-funded project Data without Boundaries (DwB) a possible roadmap for international access in Europe and beyond is presented

    Effective risk governance for environmental policy making: a knowledge management perspective

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    Effective risk management within environmental policy making requires knowledge on natural, economic and social systems to be integrated; knowledge characterised by complexity, uncertainty and ambiguity. We describe a case study in a (UK) central government department exploring how risk governance supports and hinders this challenging integration of knowledge. Forty-five semi-structured interviews were completed over a two year period. We found that lateral knowledge transfer between teams working on different policy areas was widely viewed as a key source of knowledge. However, the process of lateral knowledge transfer was predominantly informal and unsupported by risk governance structures. We argue this made decision quality vulnerable to a loss of knowledge through staff turnover, and time and resource pressures. Our conclusion is that the predominant form of risk governance framework, with its focus on centralised decision-making and vertical knowledge transfer is insufficient to support risk-based, environmental policy making. We discuss how risk governance can better support environmental policy makers through systematic knowledge management practices

    Australian co-operation with the national agricultural research project - Project Completion Report 1990

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    This Project Completion Report (PCR) has been written to meet the project monitoring requirements of AIDAB. Because the ACNARP Project was part of a larger joint WB/IFAD project known as the National Agricultural Research Project (NARP), a summary of ACNARP and its progress and achievements, cannot be divorced from NARP. The report should therefore be read within the context that ACNARP alone has not been responsible for all the developments and achievements listed. Achievements in relation to some of the project objectives have been the result of Thai inputs, often with advice from ACNARP, rather than being able to be attributed solely to ACNARP. There were also some objectives and components of the larger WB/IFAD NARP Project, for which there were no corresponding specific ACNARP inputs
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