593 research outputs found

    Land Use Change in Europe- Scenarios for a Project Area in East Germany, Poland and the Czech Republic

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    This study identifies plausible scenarios for land use changes for a project area located at the coexistent borders of Poland, the Czech Republic and East Germany. The time frame is 1992 to 2050 with an intermediate step in 2020. The basis for the scenarios is an analysis of the driving forces for land use change in the context of the study area. The main emphasis here is on the EU's Common Agricultural Policy and trends in agriculture and forestry in the three countries of the project area. In addition former land use change, spread of urban areas, the state of mining areas, recreation and nature conservation and policies related to land use planning are of importance and therefore analyzed for each country. The direction of land use change between 1960 and present was a decrease in agricultural land and an increase in forest and 'other' area, which mainly consists of urban area and area for infrastructure. Recent changes in the Common Agricultural Policy aim at reducing overproduction an cut spending in general. The prevailing tendency is to liberalize the agricultural sector to shift from product tied payments to direct payments to farmers for social, environmental or cultural duties. Since the political changes in 1989 the three countries of the project area have undergone significant economic and structural changes. East Germany as part of Unified Germany and part of the EU has experienced the most drastic restructuring of the agricultural sector with the main feature of major job losses and production decreases, especially in the livestock sector. Similar developments, though not as radical, can be observed in Poland and the Czech Republic. The first Scenario, "Large Scale Increase of Wooded Area", anticipates the introduction of a free market economy to the agricultural sector. No more subsidies are required for agriculture. Large areas of marginal farmland have to be taken out of production. The price of land decreases. Farmers will either afforest their farmland or sell it to non-agricultural uses like urban development, recreation or nature conservation are options for farmers. A quantification for the project area foresees by 2050 a decrease of agricultural land to half of its size in 1992, a doubling of forest and an increase of 'other' area by 80%. Scenario 2, "Alternative Agricultural Products", assumes a shift from food production to nonfood products, mainly biofuel and incentives for an extensification of agricultural production. Subsidies, that are still required for the agricultural sector, will be kept. The overall policy aims at keeping the land open, avoiding uncontrolled spreading of urban development and providing prospect for development and employment in rural areas. The main characteristic of Scenario 3, "Europe as Food Exporter", is an increase in the demand for agricultural products, which by approximately 2010 triggers a increase in the world market price for food products. Reasons for this are population and wealth increase, especially in China an south east Asia, combined with environmental constraints like water or fertile land scarcity and erosion. As a result agricultural production in Europe becomes prosperous in the frame of a free market environment. No further subsidies are required for the sector. Until 2010 the development is similar to Scenario 2. Scenario 2 and 3 show only modest changes in land use patterns, but the agricultural production structure differs. Scenario 2 focuses on a mixture of food and non-food products, while in Scenario 3 all available farmland is used for food production after 2010

    Measured And Predicted Behaviour Of Steel Beams And Columns In Fire

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    Hierarchically nested factor model from multivariate data

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    We show how to achieve a statistical description of the hierarchical structure of a multivariate data set. Specifically we show that the similarity matrix resulting from a hierarchical clustering procedure is the correlation matrix of a factor model, the hierarchically nested factor model. In this model, factors are mutually independent and hierarchically organized. Finally, we use a bootstrap based procedure to reduce the number of factors in the model with the aim of retaining only those factors significantly robust with respect to the statistical uncertainty due to the finite length of data records.Comment: 7 pages, 5 figures; accepted for publication in Europhys. Lett. ; the Appendix corresponds to the additional material of the accepted letter

    Predictors of self-rated health: a 12-month prospective study of IT and media workers

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    OBJECTIVE: The aim of the present study was to determine health-related risk and salutogenic factors and to use these to construct prediction models for future self-rated health (SRH), i.e. find possible characteristics predicting individuals improving or worsening in SRH over time (0–12 months). METHODS: A prospective study was conducted with measurements (physiological markers and self-ratings) at 0, 6 and 12 months, involving 303 employees (187 men and 116 women, age 23–64) from four information technology and two media companies. RESULTS: There were a multitude of statistically significant cross-sectional correlations (Spearman's Rho) between SRH and other self-ratings as well as physiological markers. Predictors of future SRH were baseline ratings of SRH, self-esteem and social support (logistic regression), and SRH, sleep quality and sense of coherence (linear regression). CONCLUSION: The results of the present study indicate that baseline SRH and other self-ratings are predictive of future SRH. It is cautiously implied that SRH, self-esteem, social support, sleep quality and sense of coherence might be predictors of future SRH and therefore possibly also of various future health outcomes

    Spanning Trees and bootstrap reliability estimation in correlation based networks

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    We introduce a new technique to associate a spanning tree to the average linkage cluster analysis. We term this tree as the Average Linkage Minimum Spanning Tree. We also introduce a technique to associate a value of reliability to links of correlation based graphs by using bootstrap replicas of data. Both techniques are applied to the portfolio of the 300 most capitalized stocks traded at New York Stock Exchange during the time period 2001-2003. We show that the Average Linkage Minimum Spanning Tree recognizes economic sectors and sub-sectors as communities in the network slightly better than the Minimum Spanning Tree does. We also show that the average reliability of links in the Minimum Spanning Tree is slightly greater than the average reliability of links in the Average Linkage Minimum Spanning Tree.Comment: 17 pages, 3 figure

    Proposal for a Performance Dashboard for the Monitoringof Water and Sewage Service Companies (WaSCs)

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    The water and sewage industry provides an essential service to the community, but it is characterized by natural monopoly tendencies of service suppliers. In this framework, it is very important to assist regulators with a small set of critical indicators (performance dashboard) for the evaluation and monitoring of the service provided by Water and Sewage Companies (WaSCs). The paper originates from the analysis of situation of Piemonte (Italy), where each regional and local body adopts a proprietary Performance Measurement System (PMS). In order to improve the coordination of information flow and to support the definition of common service standards, a methodology to merge existing PMSs and define a unique shared reference system is proposed. The Kaplan and Norton's Balanced Scorecard (BSC) is adopted as the reference model of this approach. BSC is widely recognized to be an exhaustive and balanced framework in describing the performances of an organization and ensures that all the operational aspects of WaSCs are adequately monitored. The output of the proposed procedure is a general performance dashboard for the monitoring of WaSCs. The dashboard is shown and some remarks about indicators properties are developed. In particular, this analysis highlights some common pitfalls originated by a ‘rushed' aggregation of several performance indicators. Description is supported by several example

    Cost-effectiveness of alternative methods of surgical repair of inguinal hernia

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    Objectives: To assess the relative cost-effectiveness of laparoscopic methods of inguinal hernia repair compared with open flat mesh and open non-mesh repair. Methods: Data on the effectiveness of these alternatives came from three systematic reviews comparing: (i) laparoscopic methods with open flat mesh or non-mesh methods; (ii) open flat mesh with open non-mesh repair; and (iii) methods that used synthetic mesh to repair the hernia defect with those that did not. Data on costs were obtained from the authors of economic evaluations previously conducted alongside trials included in the reviews. A Markov model was used to model cost-effectiveness for a five-year period after the initial operation. The outcomes of the model were presented using a balance sheet approach and as cost per hernia recurrence avoided and cost per extra day at usual activities. Results: Open flat mesh was the most cost-effective method of preventing recurrences. Laparoscopic repair provided a shorter period of convalescence and less long-term pain compared with open flat mesh but was more costly. The mean incremental cost per additional day back at usual activities compared with open flat mesh was €38 and €80 for totally extraperitoneal and transabdominal preperitoneal repair, respectively. Conclusions: Laparoscopic repair is not cost-effective compared with open flat mesh repair in terms of cost per recurrence avoided. Decisions about the use of laparoscopic repair depend on whether the benefits (reduced pain and earlier return to usual activities) outweigh the extra costs and intraoperative risks. On the evidence presented here, these extra costs are unlikely to be offset by the short-term benefits of laparoscopic repair.Luke Vale, Adrian Grant, Kirsty McCormack, Neil W. Scott and the EU Hernia Trialists Collaboratio

    Ward's Hierarchical Clustering Method: Clustering Criterion and Agglomerative Algorithm

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    The Ward error sum of squares hierarchical clustering method has been very widely used since its first description by Ward in a 1963 publication. It has also been generalized in various ways. However there are different interpretations in the literature and there are different implementations of the Ward agglomerative algorithm in commonly used software systems, including differing expressions of the agglomerative criterion. Our survey work and case studies will be useful for all those involved in developing software for data analysis using Ward's hierarchical clustering method.Comment: 20 pages, 21 citations, 4 figure
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