Modeling and Algorithmic Development for Selected Real-World Optimization Problems with Hard-to-Model Features

Mathematical optimization is a common tool for numerous real-world optimization problems. However, in some application domains there is a scope for improvement of currently used optimization techniques. For example, this is typically the case for applications that contain features which are difficult to model, and applications of interdisciplinary nature where no strong optimization knowledge is available. The goal of this thesis is to demonstrate how to overcome these challenges by considering five problems from two application domains. The first domain that we address is scheduling in Cloud computing systems, in which we investigate three selected problems. First, we study scheduling problems where jobs are required to start immediately when they are submitted to the system. This requirement is ubiquitous in Cloud computing but has not yet been addressed in mathematical scheduling. Our main contributions are (a) providing the formal model, (b) the development of exact and efficient solution algorithms, and (c) proofs of correctness of the algorithms. Second, we investigate the problem of energy-aware scheduling in Cloud data centers. The objective is to assign computing tasks to machines such that the energy required to operate the data center, i.e., the energy required to operate computing devices plus the energy required to cool computing devices, is minimized. Our main contributions are (a) the mathematical model, and (b) the development of efficient heuristics. Third, we address the problem of evaluating scheduling algorithms in a realistic environment. To this end we develop an approach that supports mathematicians to evaluate scheduling algorithms through simulation with realistic instances. Our main contributions are the development of (a) a formal model, and (b) efficient heuristics. The second application domain considered is powerline routing. We are given two points on a geographic area and respective terrain characteristics. The objective is to find a ``good'' route (which depends on the terrain), connecting both points along which a powerline should be built. Within this application domain, we study two selected problems. First, we study a geometric shortest path problem, an abstract and simplified version of the powerline routing problem. We introduce the concept of the k-neighborhood and contribute various analytical results. Second, we investigate the actual powerline routing problem. To this end, we develop algorithms that are built upon the theoretical insights obtained in the previous study. Our main contributions are (a) the development of exact algorithms and efficient heuristics, and (b) a comprehensive evaluation through two real-world case studies. Some parts of the research presented in this thesis have been published in refereed publications [119], [110], [109]

Qualitätsmerkmale von RFID Etiketten

Um die Qualität eines RFID Etiketts objektiv und reproduzierbar bewerten zu können sind entsprechende Qualitätsmerkmale und Prüfverfahren notwendig. In diesem Beitrag wird kurz auf Qualitätsmerkmale im Bezug auf RFID Etiketten eingegangen und die aktuelle Situation bei der Definition von Testkriterien und- verfahren dargestellt

Soft Coral Mimesis by an Aeolidiid Nudibranch

Without Abstract

The PTI Carbon Star Angular Size Survey: Effective Temperatures and Non-Sphericity

We report new interferometric angular diameter observations of 41 carbon stars observed with the Palomar Testbed Interferometer (PTI). Two of these stars are CH carbon stars and represent the first such measurements for this subtype. Of these, 39 have Yamashita (1972,1975) spectral classes and are of sufficiently high quality that we may determine the dependence of effective temperature on spectral type. We find that there is a tendency for the effective temperature to increase with increasing temperature index by ~120K per step, starting at T_EFF ~= 2500K for C3,y, although there is a large amount of scatter about this relationship. Overall, the median effective temperature for the carbon star sample is found to be 2800 +- 270K, and the median linear radius is 360 +- 100 R_SUN. We also find agreement on average within 15K with the T_EFF determinations of Bergeat (2001,2002a,b), and a refinement of carbon star angular size prediction based on V & K magnitudes is presented that is good to an rms of 12%. A subsample of our stars have sufficient {u,v} coverage to permit non-spherical modeling of their photospheres, and a general tendency for detection of statistically significant departures from sphericity with increasing signal-to-noise of the interferometric data is seen. The implications of most - and potentially all - carbon stars being non-spherical is considered in the context of surface inhomogeneities and a rotation-mass loss connection.Comment: 59 pages, 15 figures, 6 tables; accepted for publication in Ap

Proceedings of the European Workshop on the Evaluation of Farm Investment Support, Investment Support for Improvement of Processing and Marketing of Agricultural Products

Contents: i - Angela Bergschmidt, Walter Dirksmeyer and Bernhard Forstner - Proceedings of the European Evaluation Workshop – Foreword -- PAPERS PRESENTED IN THE PLENARY SESSIONS -- 3 - Stefan Meyer - Methods for the Evaluation of Investment Support -- 15 - Andrea Pufahl - Programme Evaluation of Rural Development Plans – Purpose, Approaches and Exemplary Results -- 27 - Carel Gosselink - Agri Finance: Lost without Support? -- 33 - Anne Margarian - How to Evaluate a Measure without Goals – Considerations on the Basis of the Paradigmatic Example of Farm Investment Support in Germany -- 45 - Rudy Ooijen - Ex Ante Evaluations of Rural Development Programmes – Not just an Appraisal -- PAPERS PRESENTED IN THE SESSION ON FARM INVESTMENT SUPPORT -- 61 - Angela Bergschmidt and Walter Dirksmeyer - A Comparison of Farm Investment Support in Selected EU Member States -- 69 - Monika Beck and Thomas Dogot - The Use of Impact Indicators for the Evaluation of Farm Investment Support – A Case Study Based on the Rural Development Programme for Wallonia (2000 – 2006) -- 79 - Barbara Costantini and Maria Cristina Sibilla - Implementation of Farm Investment Support in Italy – Mid-Term Analysis -- 93 - Pawel Chmielinski - Regional Absorption Capacity of Farm Investment Support in Poland -- 105 - Luis A. Collado Cueto - Effectiveness and Impacts of Farm Investment Support in Spain – The Experience of the Updated Mid-Term Evaluation (2000 – 2006) -- 121 - Dimitros Lianos and Triantafyllia Giotopoulou - The Experience of the Evaluation of Farm Investment Support in Greece -- 133 - Bernhard Forstner - Evaluation of Farm Investment Support in Germany – Lessons Learned from the Application of Different Approaches -- 147 - Stephan Pfefferli - Impact Analysis of Investment Support for Agricultural Buildings in Switzerland -- 159 - Justyna Ziólkowska, Joanna Nargiello and Cezary Klimkowski - The Analysis of Changes in Farm Investment Support Policy in Poland after Joining the European Union -- PAPERS PRESENTED IN THE SESSION ON INVESTMENT SUPPORT FOR IMPROVEMENT OF PROCESSING AND MARKETING OF AGRICULTURAL PRODUCTS -- 177 - Inge Uetrecht, Heinz Wendt, Volker Krah and Annette Trefflich - The Implementation of Investment Support for Improving Processing and Marketing of Agricultural Products in the EU Member States – An Overview -- 187 -Andreas Pölking - Synthesis of the RDP Mid-Term Evaluation in Germany (16 Länder) and EC 15 in 2005 – Methodologies, Possibilities, Pitfalls and some Selected Results -- 195 - Julia Neuwirth and Karlheinz Pistrich - Improving Processing and Marketing of Agricultural Products – Organisation, Problems and Results of Evaluation in Austria -- 201 - Alois Grabner - Improving of Processing and Marketing of Agricultural Products – Assessment of Projects -- 205 - Pedro Serrano - Support to Processing and Marketing of Agricultural Products in Portugal -- 215 - Mark Temple - Two Approaches to Evaluation – The Case of the Processing and Marketing Grant in England -- 227 - Jochen Nölle and Josef Efken - Does Complete Field Research Build a Good Basis to Evaluating the Measure? -- CLOSURE OF THE EUROPEAN EVALUATION WORKSHOP -- 241 - Bernhard Forstner and Heinz Wendt - Summary and Final Discussion --

Methoden zur Bestimmung der Schneefallgrenze

Um die Lage der Schneefallgrenze prognostizieren bzw. diagnostizieren zu können wurden im Lauf der Zeit verschiedenste Methoden und Modelle entwickelt. Während für die Vorhersage Schichtdicken einen guten Richtwert geben können, sollten bei der Analyse aufgrund der besseren zeitlichen Auflösung Stationsmesswerte verwendet werden. In der vorliegenden Arbeit wurden unterschiedliche Methoden getestet und ein Vergleich der Ergebnisse zwischen Wien und Innsbruck angestellt. Dazu wurden Radiosondenaufstiege bei Niederschlag und einer Feuchttemperatur unter 3 °C ausgewertet. Dabei zeigt sich, dass je dünner eine Schicht ist, desto kleiner ist der Bereich in dem sich der Übergang von festem zu flüssigem Niederschlag vollzieht. Die Analyse der Schichtdicken zwischen 1000 und 850 hPa hat ergeben, dass bei Dicken unter 1290 m mit Schnee, bei Dicken größer 1300 m mit Regen zu rechnen ist. Im Allgemeinen sind die Schichtdicken bei Schneefall in Wien größer als in Innsbruck, ein Resultat, welches auf den Einfluss der Druckreduktion zurückzuführen ist. Ein weiterer Schwerpunkt lag auf der Analyse der Stationsmesswerte bei Niederschlag. Ziel war es dabei eine Methode zu finden bei Kenntnis der Messwerte von automatischen Stationen eine Aussage über die Niederschlagsart treffen zu können. Am besten eignet sich dazu die Feuchttemperatur. Die vorliegende Untersuchung hat diesbezüglich gezeigt, dass sich der Übergang von Schnee und Regen in Wien zwischen 1,1 und 1,4 °C Feuchttemperatur vollzieht, in Innsbruck zwischen 0,7 und 1 °C. Bei höheren Werten ist mit einer Wahrscheinlichkeit von 66% mit Regen, bei niedrigeren mit Schneefall zu rechnen. Die Feuchttemperatur bei der gleich viele Fälle mit festem und flüssigem Niederschlag beobachtet wurden beträgt in Wien 1,2 °C in Innsbruck 0,9 °C.In order to forecast and analyse the height of the melting layer a range of different methods and models have been developed over time. As far as the forecast is concerned, the thicknesses of the layer between different pressure levels represent a good indicatory value. Concerning the analysis, however, data from the weather station should be applied due to the fact that they have a better temporal resolution. The focus of this thesis lies on testing different methods and conducting a comparison between the results concerning Vienna and those concerning Innsbruck. For the purpose of this study, ascents of radiosondes were analysed during precipitation and at a wet-bulb temperature of below 3 °C. The study has yielded the following results, namely, that the thinner the layer, the smaller the range at which the transition from solid to liquid precipitation takes place. Furthermore, the analysis of the layer thickness between 1000 and 850 hPa has shown that snow is expected at thickness below 1290 m, whereas rain is expected at thickness at 1300mand above. The analysis of the station results under the condition of precipitation constituted another main focus of this study whereby the aim was to find a method which allows us to make assertions concerning the type of precipitation based on the data provided by automatic stations. The wet-bulb temperature has proven to be the most suitable data for this purpose. Regarding this issue, the analysis at hand has shown that in Vienna the transition from snow to rain takes place between 1,1 and 1,4 °C wet-bulb temperature whereas in Innsbruck it takes place between 0,7 and 1 °C. At higher values there is a 66% chance of rain, and at lower values snowfall can be expected. The wet-bulb temperature amounts to 1,2 °C in Vienna and 0.9 °C in Innsbruck whereby the same number of cases of solid and liquid precipitation have been taken into account