Naturwissenschaft, Mathematik, Informatik

The max-cut problem is an NP-hard combinatorial optimization problem defined on undirected weighted graphs. It consists in finding a subset of the graph's nodes such that the aggregate weight of the edges between the subset and its complement is maximized. This book deals with a new separation approach to be used within a branch-and-cut algorithm for solving max-cut problems to optimality. The method is based on graph contraction and allows the fast separation of so-called odd-cycle inequalities. In addition, we...

The outstanding importance of phosphorus (P) in all living cells makes it an essential nutrient. Its pivotal use as a fertilizer and the finiteness as a natural resource lead to a new episode of historic importance: A possible upcoming phosphate crisis. In this book an overview on the role of phosphorus as a nutrient and as a fertilizer as well as the underlying soil dynamics is given. The flows of phosphorus in Austria are shown by using the method of...

Seit dem Beginn der Weltraumfahrt hat sich eine enorme Anzahl menschengemachter Müll im All angesammelt, sogenannter Weltraumschrott (Space Debris). Dieser Schrott stellt eine immer größer werdende Gefahr für Satelliten und Raumfahrzeuge dar. Schon zentimetergroße Teilchen können bei einer Kollision mit einem Satelliten eine zerstörerische Kraft entfalten. Als Zweitziel der astronomischen Mission AsteroidFinder des DLR, deren primäres Ziel das Aufspüren erdnaher Asteroiden ist, wurde die weltraumgestützte Detektion von Space Debris definiert. Die weltraumgestützte Beobachtung hat den Vorteil, dass keine Atmosphäre die...

The current work investigates two fundamental problems of small molecule organic solar cells (OSC): transparent top contacts and alternative donor materials. Transparent top contacts are a prerequisite for inverted, i.e. top-illuminated OSC on opaque substrates. This work documents that transparent, ultra-thin metal films are a possible solution to this challenge. It is shown that silver or gold layers with thicknesses < 20nm are sufficiently transparent and conductive to fabricate suitable OSC. Utilisation of nanometer-thin Al interlayers between Ag or Au...

Das Buch beginnt mit einer für Leser aller Fachbereiche verständlichen Einführung in die methodologischen und begrifflichen Grundlagen des Organic Computing. Die interdisziplinäre Forschungsinitiative nimmt Bezug auf das biologische Paradigma selbstorganisierter Informationsverarbeitung in organischen Systemen. Schon die einfachsten biologischen Organismen zeigen spezifische phänomenale Merkmale, wie Zielgerichtetheit und Anpassungsfähigkeit, deren wissenschaftliche Erklärung innerhalb der Theorie dynamischer Systeme die Entwicklung einer organisch strukturierten Informationstechnologie ermöglichen soll. Doch zwischen der formalen Darstellung dynamischer Prozesse und den phänomenalen Merkmalen organischer Systeme besteht eine Erklärungslücke, die...

History has witnessed forests shaping human civilization from the ancient times to the industrial ages and after. In recent years, the world's forests have staged more prominent roles in our society. That the year 2011 has been declared as the International Year of Forests by the United Nations reveals a bold statement on such importance. The forests of Indonesia are in particular; stakes placed upon are diverse and often conflicting, not only from local or national levels but also from...

The dissertation will address the concept of a proto-universe that combines a steady state model of universe creation with multiple nucleogenesis events. Based on observable data of many large scale structures found in the universe that are older than the 13.7 billion years given for the big bang model of the birth of the universe. Details Titel: An Architecture for an Ur-Universe Untertitel: Sequential Universal Events Autor: Dr. Bradley S. Tice Auflage: 1. Auflage Hochschule: Northwestern International University Erschienen: 1....

In der Größenordnung weniger Nanometer zeigt Silizium neue Eigenschaften. Das Besondere an nanokristallinem Silizium ist das Auftreten von Quanten-Effekte. In dieser Diplomarbeit wurde untersucht, ob sich bestimmte Nanostrukturen, wie z.B. ein Übergitter mit Nanokristallen aus Silizium, für die Photovoltaik eignen bzw. Quanten- Effekte für die Energiekonversion genutzt werden könnten. Hierfür wurden neun verschiedene Solarzellen mit Quarzglas (als nicht-photoaktives Substrat) hergestellt, um den photovoltaischen Effekt von Nanostrukturen einer Analyse zugänglich zu machen. Nach einer ausführlichen theoretischen Behandlung des photovoltaischen Effekts mit...

Three local carrot cultivars from Myanmar and two hybrid cultivars from Germany were investigated for their yield and nutritional quality supplied by mineral or organic fertilizers. Root yield and nutritional qualities were affected by cultivar difference and fertilizer types. Details Titel: Agronomic characteristics and nutritional quality of carrot (Daucus carota L.) cultivars from Myanmar and Germany as affected by mineral and organic fertilizers Autorin: Dr. Le Le Win Auflage: 1. Auflage Hochschule: Georg-August Universität Göttingen Erschienen: 1. Aufl. 20.09.2010 Fachbereich:...

The present dissertation is focused on the phylogenetic, biochemical, structural and physiological analysis of the hydratases from Streptococcus pyogenes M49 and Lactobacillus acidophilus NCFM. These hydratases belong to myosin cross-reactive antigen (MCRA) protein family for which knowledge on the biochemical and physiological function is scarce. This study provides the first line of evidences on biological significance of this protein family as ubiquitous bacterial enzymes which metabolize highly toxic unsaturated fatty acids to their less toxic and more soluble hydroxy derivatives....

Twenty eight genotypes of tomato were organically cultivated in two locations (Schönhagen and Ellingerode, Germany) in different two years. Plant infection by Phytophthora infestans was evaluated as well as the fruit nutritional and quality parameters (content of lycopene, phenolic compounds, ascorbic acid antioxidant capacity, mineral nutrients and organic compounds). It was also of interest to find a connection between infection and fruit quality. Details Titel: Organically-grown tomato (Lycopersicon esculentum Mill.) Untertitel: Plant infection by Phytophthora infestans and fruit quality Autor:...

Ackee is an underutilized species native to West Africa important for the livelihoods of rural population and candidate species for domestication. However, because the species was neglected for so long, key knowledge essential to elaborate a clear domestication strategy is very sketchy in the region. This book provide data from Benin on farmer's indigenous knowledge and perception of variation taking into account the difference among ethnic groups and gender, the morphological variability in tree and fruit traits in relation to...