Bøger udgivet af Cuvillier

One of the most important developing fields is that of digital communication. This is due to the demand for an increasingly higher speed in the exchange of information, which is presently growing at an exponential rate. In fact, considerable efforts have been made towards the realization of low-power miniaturized radio frequency components. However, issues related to design and fabrication of efficient, ultra-compact, and easily integrate-able microwave components appear to be challenging. Many unit cells are needed in order to achieve high efficiency components, such as filters and couplers, whose dimensions are comparable or larger than a single wavelength cycle. However, during the past decade, metamaterials, a novel class of artificial materials, have become a field of active research in physics and engineering. These metamaterials offer unique electrodynamic properties, which are neither available in any natural material nor observable in the materials presently used in state-of-the-art technology. Furthermore, a metamaterials unit cell is much smaller than the wavelength of reference.The main objective of my dissertation was to design and realize new resonator structures to meet the challenges of simple, high performance, and miniaturized microwave circuits as well as terahertz components for filtering and sensing applications. First of all, I suggested a series of novel structures for filter applications. They consist of only a single metal layer, an approach which I suggested for the first time worldwide. Later on, I realized more advanced miniaturized resonators based on the same idea.

The aim of this dissertation is to demonstrate that the development of a management model for National Parks Management in Chile that is based on the principles of responsible tourism will increase economic, social and environmental benefits for the communities living in and around Chilean National Parks. The thesis, in reference to the primary and secondary research, reveals that the exemplifying National Park ¿La Campanä can be an internationally attractive responsible tourism product in reference to the introduction to the international market. However, the thesis indicates that one major consideration needs to be pointed out. The success of such an initiative for engaged community participations predominantly depends on the time dedicated by the other stakeholders to making community members aware of tourism-related impacts and how this affects their life and livelihood.

Sarah ANYANG AGBOR¿S text is a conceptual, historical and functionalexamination of Commonwealth Literature. The text comes acrossas a nice way to review some of the essential conceptual andhistorical development of Commonwealth literature. This text will beof special interest for students in Commonwealth studies.The workresponds to two ways of looking at Commonwealth literature. The fi rstis a conceptual defi nition, historical development and diversifi cationof Commnwealth Literature. The other is to investigate through sociologicalcriticism the various ways Commonwealth Literature dissents .This comparative analysis which is not limited to authors and regionsbut extends to the erstwhile and the contemporary, offers invaluableinsights into the longstanding debates surrounding the concept ofCommonwealth Literature in particular and draws conclusions thatdo not pretend to close the debate but rather articulate the discursivenature of Commonwealth Literature and the ambivalence of its ¿defi -ning¿ parameters.

Previous studies carried out by the Biosensor Research Group of the Institute of Clinicaland Experimental Transfusion Medicine at the Tübingen University had successfullydemonstrated determination of various blood types through the interaction oferythrocytes with immobilised antibodies on a QCM. These studies have opened thepossibility to test new applications of this technique for the study of infectious diseases.In our case, studies of the erythrocyte life cycle of P. falciparum, particularly during the lastsix hours preceding the merozoite release and studies related to reinfection of bymerozoites were the focus of our investigation.Release of malaria parasites of P. falciparum from infected erythrocyte at the end of theirasexual erythrocyte cycle occurs approximately every 48 hours, asynchronously in parasiteculture and synchronously in vivo. This process is poorly studied due to: (I) merozoiterelease is a very short event (

The aim of this study is to provide decision-makers and researchers with an understanding of the positive role that information systems (IS) and information technologies (IT) can play in the struggle against climate change. Owing to its extensive use of resources and energy, IT is part of the global environmental problem. However, IT also enables new IS, which help to solve the global environmental crisis. Theories and concepts that support environmentally sustainable information management and provide scientists with a starting point for further research in this field are the main contributions of this thesis. Environmental protection is commonly classified under the overarching sustainability concept. Sustainability covers economical, ecological, and social dimensions, providing a solid basis for this research. Although sustainability has been researched in general management, it has not been studied in terms of IS. Drawing from the resource-based view, stakeholder theory and transaction cost theory, this thesis provides two contributions to incorporate and manage sustainability in IS, for which a procedural model for sustainable IS management is developed. After describing sustainability in IS, the potential for IT-enabled environmental initiatives is highlighted, which is called ¿Green IS¿. A survey in which 500 people participated indicates that the market share for IT with green features could be 26.6%. The findings show that the marketing mix should emphasize disposal attributes, rather than energy attributes, and it should focus more on female rather than on male customers. This example demonstrates the overall market relevance of environmentally sustainable IT.

Advances in molecular genetics and recombinant protein (rDNA) technology lead to anincreasing availability of protein-based biomolecules1. In contrast to conventional lowmolecular weight synthetic chemical drugs protein drugs provide a relatively high specifityand activity at low concentrations2. Therefore, today protein drugs represent a fast-growingclass of therapeutic molecules1,3. Protein-based drugs offer a multitude of new therapeuticoptions, mainly for the treatment of severe and chronic diseases such as autoimmune orcancer diseases2. However, with the increasing number of ¿new biologic entities¿ passingthrough development and manufacturing and finally reaching patients, also unprecedentedchallenges for the design of stable, safe and convenient formulations are encountered4.The first obvious formulation challenge to be faced concerns the delivery of protein drugs.Oral delivery ¿ which is generally the preferred and most widely applied route of drugadministration ¿ is not feasible with protein drugs.

In the past few years, growing attention has been devoted to the study of the interactions taking place in mixed systems of phospholipid membranes and inorganic nanoparticles. This is an important issue with regard to using nanoparticles in nanomedicine but also in the related field of nanotoxicology. However, the nature of the interactions in such mixtures is rather complex and may lead to the formation of different colloidal structures. Focusing on the case of liposomes and silica nanoparticles, the study presented here aims at improving our understanding of the interactions in such mixed systems and at obtaining a detailed picture of the hybrid structures they result in. Drawing a parallel between different systems, this work offers not only interesting features on the internalization process of nanoparticles and on the stability of nanoparticle¿decorated vesicles but also comprehensive insights into the influence of the bilayer state (liquid, gel) on the nanoscale structures of hybrid liposome/nanoparticle complexes.

The book is divided into seven sections and comprises forty-one articles from scholars from different persuasions and temperaments. It also includes an interview with the honouree. The major thrust of the collection centres on the place of the humanities in a drifting world and the need to chart a fresh course of action that could restore hope to humanity. The contributions also represent a melting-pot for the various branches of humanistic scholarship. We hope this book would serve as a resourceful compendium for scholars, students, policy makers and all lovers of knowledge production and dissemination¿

The overall aim of this study has been to show that incantations from the Western Grassland region of Cameroon derive their essence from the people¿s religious beliefs and practices and that they reveal a perception of the universe as an ordered system, a whole. This whole comprises many structures, from inorganic matter to man, the inanimate, animate, celestial, and spirit worlds ¿ all these reduced to the physical and metaphysical realms of existence.From a purely metaphysical point of view, the structures that constitute the universe form a hierarchy of perfections or degrees of being. The most elementary structure of reality is that of inorganic matter ¿ the lowest level of perfection in the visible universe. Above the level of inorganic matter are the various levels or degrees of life. Life, on whatever level it can be considered, manifests itself as a real and active synthesis, that is, the reduction of diversity to unity. Vegetative life utilises inorganic matter and reduces the diversity of this matter to the unity of an organism. The next level of life ¿ sensory or animal life ¿ utilises in its turn vegetative life. And, finally, the highest level of life ¿ the spiritual or intellectual and volitional life of man ¿ presupposes and utilises a very highly developed form of sensory life. Here, the reduction of diversity to unity reaches its maximum, for in human life the sense-knowledge and sense-affections of purely animal life are transcendently unified in the ideas and value of the spiritual self, linking man to the spirit world.

The rapid diffusion of information and communication technologies (ICT) is believed to be one of several important drivers of international trade and globalisation. The purpose of this dissertation was to analyse whether the three ICT ¿ fixed telephone lines, mobile phones, and the internet ¿ has encouraged international trade in important agri-food products. Gravity models of bilateral trade between countries were chosen to explain international trade. We used panel data of the values of bilateral trade between pairs of countries for the period 1995 to 2009. The empirical results from OLS and negative binomial regression estimation suggest that ICT has an effect on international trade in agri-food products. The impact is, however, not always strong and, contrary to expectations, it is often negative. For the products, ¿wine¿ and ¿fruit and vegetable juice¿, we found no effect of ICT on trade at all. Although there is great variation in the estimated impacts of individual ICT on international trade, the impact of mobile phones is somewhat stronger than that of fixed telephone lines and of the internet.

Forests and any other trees outside the forest play a relevant role all three great UN conventions on Climate Change, on Biodiversity, and on Combating Desertification. The policy processes to implement the measures in these conventions on sub-national, national, regional and international level are extremely complex. And that complexity comes, among other factors, from a blend of different sectoral and national interests, from a large number of scientifically not yet entirely resolved issues and a wide range of different biophysical, social, cultural and political conditions all over the world.The 3rd International DAAD Workshop on ¿Forests in Climate Change Research and Policy: The Role of Forest Management and Conservation in a Complex International Setting¿ held in Dubai and Doha along the conference of the parties (COP18) from 28st November to 2nd December had a strong focus on the role of forests and their management in context of international conventions and recent international and national policy. The volume contains 20 papers that are grouped under the topics The Role of Forests and their Management under Climate Change, International Policy Processes, Technical Issues on Remote Sensing, and Country Cases on Forest Management under Climate Change.

Dynamic capabilities describe the firms' capacity to adapt their resources with regard to external shifts in order to maintain or to even enlarge competitive advantage. In this essay the author pursues three research objectives regarding dynamic capabilities. First, based on a literature review the author states that no appropriate dynamic capability concept exists that enables an empirical investigation of dynamic capabilities across industries, however, argues that such an investigation is possible, and outlines a first step to do so. The second research objective is focused on the value of dynamic capabilities. Using real option knowledge the author is able to outline a simple mathematical model. The results show that the value of a firm is not only given by the expected value, generated by the firm's resources in place, but also by the firm's options to react to environmental changes. Besides other externally given factors - like market development - the application of dynamic capabilities in terms of time has consequences on the expected firm value. The third research objective deals with the basic challenge of ambidextrous firms to achieve an optimal balance of exploitative and explorative activities with regard to market developments. Again, using real option knowledge the author is able to demonstrate that there exist defined points in time until when to maintain, stress, taper off and finally stop exploitative and explorative activities. A further development of the model even enables the prediction of the value maximizing points in time.

Understanding the structure-property relationship of enamel is a basis to improve restorative and preventive dentistry. The structure-mechanical properties relationship of dental enamel (made of apatite fibers and a small amount of organics and water) was studied. Enamel¿s elastic moduli, elastic/inelastic transition were quantified and the toughening mechanisms were identified for different hierarchical levels. During creep, the interrod regions are able to dissipate higher irreversible energy compared to the enamel rod regions. For enamel fracture, the crack tip toughness, the cohesive stresses and size of the cohesive zone at the crack-tip were quantified.

Injection into geological formations is seen by many as a short to medium term measure to reduce emissions of CO2 to the environment and as such to slowdown the pace of global warming. The injection process requires that the fluid flows effectively into the host formation. To this end it is very important to accurately predict the pressure and temperature of the fluid along the well and especially at the bottom of the hole. In the present dissertation a rigorous procedure to estimate fluid pressure and temperature along CO2 injection wells has been developed based on analytical modeling. The procedure accommodates wellbores of varying diameter, varying deviation angles, non-uniform tubing strings and layered formations with different thermal properties and varying geothermal gradients.To test the models, computer codes have been written with Visual Basic.Net language on the Microsoft Visual Studio Platform. The codes are encapsulated in a user-friendly Graphical User Interface.The simulated results are compared with field observed data from a shallow aquifer injection vertical well in Germany (Ketzin) and that from a relatively deeper offshore aquifer injection slanted well in Norway (Snøhvit). The maximum deviation is around 2% for pressure and around 10% for temperature.

Non-cooperative spacecrafts are those current or future assets in orbit which havelost their control authority in one or more degrees of freedom and cannot convey anyinformation concerning their position, attitude or rates to facilitate Rendezvous andDocking/Berthing (RVD/B) process. A growing ¿eld of study in space research is todevelop On-Orbit Servicing (OOS) technology capable of dealing with these space-crafts, called targets, which are designed without any intention to be serviced. Torender services such as repair, refuel or removal of the target from orbit, the chaserspacecraft should exhibit sophisticated RVD/B technology for formation ¿y and ¿nalstage docking/berthing operations of the mission.Assuming that the terminal capture operations of the target are to be performedby a suitable manipulator system on-board chaser, this study relies upon proventechnology and outlines guidance and control methodologies to achieve rendezvousduring proximity phases. The entry gate of chaser after phasing can be de¿ned at adistance of about 5 km in ± V-bar direction from the target in its orbit. To accountfor errors in modeling, navigation or actuation, proximity range operations from theentry gate are decomposed into three di¿erent subphases as far range, inspection or¿y around and closer approach.From the entry gate and along the path of the chaser two hold points are de¿ned:¿rst to initiate an inspection and the second, which is close to the safe zone de¿nedaround the target, to initiate a capture. The chaser is assumed to perform a stationkeeping maneuver at the second hold point until initial conditions for the capture aremet. Possible scenarios pertaining to the behavior of the target in a circular orbitare considered and guidance schemes for di¿erent subphases are presented using acombination of Hill-Clohessy-Willtshire (HCW) solution, elliptical ¿y around, glides-lope algorithm etc. Relative controllers both for position and attitude of the chaserare also presented. A Linear Quadratic (LQ) controller for relative position and aProportional Integral Derivative (PID) controller for relative attitude with angularvelocity constraints are chosen to track down the error to achieve rendezvous andattitude synchronization with the non-cooperative target. A comparative analysisbetween di¿erent guidance trajectories for important parameters such as time, fuelusage, minimum absolute distance and the maximum radial distance from the targetis presented. Veri¿cation of the proposed guidance and control methods is done byapplying them to two di¿erent case studies: the ¿rst study incorporating a stabilizedtarget in Geostationary Earth Orbit (GEO) and the second, with a spinning targetin Low Earth Orbit (LEO).The methods presented here are general and provide a simulator to the chaser toperform rendezvous analysis with non-cooperative targets. To achieve RVD/B, thestudy proposes a careful combination of guidance solutions for di¿erent phases ofproximity operations, and for di¿erent scenariös of the target encountered by thechaser.

Ethiopia is the second largest wheat producer in the sub-Saharan Africa. The country is rich in genetic resources of tetraploid wheat and has suitable environments for wheat production. However, the country is a net importer of wheat particularly durum wheat (hard wheat). The demand for durum wheat is continuously increasing because of the new emerging food processing industries. But the productivity of wheat in Ethiopia is low due to biotic and abiotic stresses. Among the biotic factors, diseases particularly stem rust play a significant role in yield reduction. As a result of a recent spread of a new and highly virulent race of Puccinia graminis f. sp. tritici (Pgt), Ug99, stem rust is becoming a serious threat to wheat production in Ethiopia as well as in other East African and wheat producing countries. Therefore, it is important to identify new resistance sources and to apply marker assisted selection for sustainable and efficient control stem rust.The aims of the studies included in this thesis were (i) identification of QTL and test for epistatic effects in a segregating population for resistance to stem rust, (ii) identification of stem rust resistance (Sr) genes that are present in durum wheat (Triticum durum Desf.) varieties that were released in Ethiopia during the period 1966¿2009 and tetraploid wheat landraces using linked/diagnostic molecular markers and (iii) Evaluation of genetic diversity and relationship pattern within and among these tetraploid wheat landraces and improved varieties based on SSR/STS markers including those linked with reported stem rust resistance genes and QTL.Across all the three experiments, our study demonstrates that there exist potential germplasm and strategies to combat the threat posed by Ug99 and its derivatives. These results provide useful information to wheat breeders in Ethiopia and other national and international programs, regarding the use of available landraces and released varieties for the enhancement of the genetic base of wheat germplsm. Particularly it will give an alarm for Ethiopian wheat breeders to broaden the genetic base of the varieties that will be released in the future since most of the varieties released for the last five decades have a narrow genetic base. In addition, our research provides a base of knowledge for future QTL and gene mapping conferring resistance to stem rust and the use of the linked markers in marker assisted selection.

Uluguru Mountains is one of the Eastern Arc Mountain blocks that stretch from Taita Hills in Kenya to Udzungwa Mountains in south-central Tanzania. The Uluguru Mountains contain several forest fragments, which are recognized as important biodiversity hotspots. The population pressure and encroachment threatens their biodiversity values. This study analyses (1) species richness, diversity, floristic similarity and structure of trees species (DBH ¿ 10 cm) in the forest fragments in Uluguru, (2) Understory species composition and natural regeneration of the fragments (3) changes in species richness, diversity and tree density along the edge-interior gradient in the fragments and (4) indigenous tree use, use values and human population impacts on tree density and species richness in Uluguru forest fragments.

The need for a comparative empirical approach to academic writing has become evident during the development of new MA and PhD programmes in the so-called Bologna process, where academic skills components had to be included. This is not only because more and more students even at postgraduate levels seem to lack the skills that have been taken for granted for a long time at European universities or that were considered part of the autonomous efforts of young scholars themselves and not the responsibility of their teachers. This is also because with the further expansion of English as THE language of science and international cooperation during the last few decades, new challenges and opportunities have arisen for English specialists.On the one hand, there seems to be a standardising trend in international writing that discourages national styles and traditions in specific disciplines and genres that scholars need to be aware of, if they want to take part successfully in international science discourse. On the other hand, English departments and English graduates in Europe may be able to prove their ¿usefulness¿ by research and teaching in the expanding field of academic writing.

Species-rich semi-natural grasslands with low-intensity management have a high nature conservation value. Due to the low digestibility of the mature herbage at the usually late cutting dates of these grasslands, their use in animal nutrition is limited. As a result, semi-natural grasslands are threatened by either intensification or abandonment of management in many parts of Europe. Production of bioenergy from semi-natural grassland biomass is an alternative utilization that can help to keep up the low-intensity agricultural management necessary for the conservation of these grasslands. Combustion is a particularly well-adapted conversion technology for the decentralized utilization of lignocellulosic biomass. However, as semi-natural grasslands have low biomass yields and the harvested biomass has a low energy density, it is not evident if its combustion will result in relevant net energy production and relevant greenhouse gas emission savings. Compared to other biomass fuels, moreover, few studies have focussed on the content of combustion-relevant elements in semi-natural grassland biomass. Available information points towards a sometimes problematic chemical fuel composition with high variability.On the basis of a long-term field experiment with for management intensities, a life cycle assessment of semi-natural grassland biomass combustion was performed. Cumulative energy consumption and global warming potential of the experimental variants without N fertilization were 87-91% lower than those of a fossil fuel reference scenario. Acidification potential, however, was higher than in the reference scenario due to nitrogen oxide, sulphur dioxide and hydrogen chloride emissions.

The present study provides experimental and mathematical methods for the understanding and quantification of the water fluxes and solute transport in heterogeneous layered porous groundwater systems characterised by differences in hydraulic conductivities.On the one hand, multi-layered porous groundwater systems with different hydraulic conductivities are characterised by a heterogeneous flow field, which causes a heterogeneous mass transport. On the other hand, extreme differences in hydraulic conductivities create regions of immobile water which influence the mass transport. These two different structural heterogeneities ¿ variable hydraulic conductivities and immobile/stagnant water zones ¿ were investigated experimentally in different laboratory aquifer models.