Bøger udgivet af Cuvillier

Over the last decade, the market for organic food products in Germany has grown steadily, as consumers become increasingly aware of credence characteristics of food products. The primary goal of this study is to integrate psychometric data into a choice experiment to examine preference heterogeneity among consumers and their willingness-to-pay for organic products. In particular, the role of trust and gender are considered in analysing both preferences and willingness-to-pay for organic products. The results of the mixed logit models reveal significant heterogeneity in preferences among consumers for the products examined. The second focus of this study is the effect of starting point bias on the willingness-to-pay estimates obtained. The use of different prices in the first choice set results in different distributions of choices and significantly different preferences and willingness-to-pay estimates in two otherwise identical choice set designs. The results of the latent class models indicate that consumers¿ trust perceptions tend to significantly influence their preferences for organic food products. The findings of this study indicate that some consumer groups are willing to pay high price premiums for specific organic food products and, to some extent, for locally produced food. As there is consumer segmentation based on varying levels of trust and due to the heterogeneous preferences of the consumers, organic food marketing should increase its use of suitable communication strategies concerning quality attributes.

The present work evaluated the effect of mineral nitrogen (N) fertilizer application during crop production on the potential risk of gaseous N loss in the form of nitrous oxide (N2O). Nitrous oxide (N2O) is an environmentally important atmospheric trace gas and contributes to the anthropogenic greenhouse effect. In addition, it is a precursor to photochemical nitric oxide (NO) production in the stratosphere which leads to stratospheric ozone depletion. Agriculture is considered to be the main source of anthropogenic N2O, with agricultural soils representing the single largest source due to nitrogen fertilizer applications during crop production.The purpose of this study was to examine the effects of mineral N fertilizers (N form, amount, mode of application) on N2O emissions from fertilized croplands in north-west Germany. Therefore several field trials, one greenhouse pot experiment and two incubation experiments were conducted. Nitrous oxide fluxes were measured by means of the closed chamber method. The length of the experimental period varied between experiments from several weeks (42 days) up to one-year measurement campaigns.The amount of N2O emitted during the crop growth period depended on the N form applied as well as on the mode of application, and a linear relationship between cumulative N2O emissions and total N fertilizer amount applied was found.

Magnetic singularities in micron-sized ferromagnetic elements have been proposed for new concepts of magnetic data storage and are an ideal model system for the investigation of magnetization dynamics. This thesis deals with the dynamics of magnetic vortices as well as antivortices at picosecond and nanosecond timescales. High frequency alternating fields and spin-polarized currents are used for the manipulation of the vortices¿ magnetic states. The special case of rotational excitation is investigated by time-resolved magnetic transmission x-ray microscopy, micromagnetic simulations, and analytical calculations. For magnetic antivortices we find an asymmetric response to field and current excitation that we can explain with the negative winding number of their domains. In addition, we study the dynamics of magnetic vortices in the frequency domain by means of ferromagnetic absorption spectroscopy. We find deviations from the linear dynamics that we assumed previously. These deviations are explained in the context of a nonparabolic confining potential and a critical maximum velocity of vortex motion. Absorption spectra are found to be crucially influenced by the continuous reversal of the vortex-core polarization for high amplitudes of excitation. The insight into vortex dynamics gained in this work is crucial for a successful application of vortices for data storage devices.Magnetische Singularitäten in mikroskopisch kleinen, ferromagnetischen Dünnfilmelementen könnten in der Zukunft in magnetischen Speichermedien Verwendung finden. Des Weiteren stellen sie ein ideales Modellsystem für die Untersuchung der Magnetisierungsdynamik dar. Diese Arbeit behandelt die Dynamik magnetischer Wirbel, der sogenannten Vortizes und Antivortizes, auf Zeitskalen von wenigen Pikosekunden bis zu mehreren Nanosekunden. Hochfrequente magnetische Wechselfelder und spin-polarisierte Ströme werden genutzt um die magnetischen Zustände dieser Strukturen gezielt zu verändern. Mittels zeitaufgelöster Röntgenmikroskopie, mikromagnetischer Simulationen und analytischer Berechnungen untersuchen wir den speziellen Fall einer rotierenden Anregung. Für magnetische Antivortizes erhalten wir ein asymmetrisches Verhalten bezüglich der Feld- und Stromanregung, welche auf die besondere, negative Windungszahl der Domänenstruktur zurückzuführen ist. Zusätzlich erforschen wir die Dynamik magnetischer Vortizes im Frequenzraum mittels ferromagnetischer Absorptionsspektroskopie. Hierbei finden wir Abweichungen von den zuvor entwickelten linearen Bewegungsgleichungen. Diese Abweichungen lassen sich jedoch durch die Annahme nicht-parabolischer Einschluss-Potentiale und einer kritischen maximalen Geschwindigkeit der Vortexbewegung erklären. Es stellt sich heraus, dass die gemessenen Absorptionsspektren ab einer gewissen Anregungsamplitude grundlegend durch das kontinuierliche Schalten der Vortex-Polarisation beeinflusst werden. Der Einblick, der durch die vorliegende Arbeit in die Dynamik magnetischer Wirbel gewonnen wird, ist Grundlage für eine erfolgreiche Anwendung magnetischer Vortizes als Speichermedium.

Chiral molecules exist in two geometric configurations of their atoms with mirror-image symmetry, which are called enantiomers. Many natural and organic molecules are chiral, such as peptides, enzymes, many amino acids or proteins. Despite similar physical and chemical properties, enantiomers may have very different biochemical and physiological effects being of great interest for the development of new pharmaceutically active compounds. Optical methods provide a direct means of distinguishing the enantiomers due to their differential interaction with circularly polarized light. This difference is generally referred to as Optical Activity.This book presents and evaluates new optical methods for the detection of Optical Activity in refraction, absorption and scattering. Beside different concepts for a Chiral Refractometer allowing the measurement of Optical Activity in microfluidic volumes the first realization of a VCD spectrometer based on a Quantum Cascade Laser is shown. It enables Optical Activity studies in strongly absorbing solvents like water. Finally differential scattering experiments are used for the characterization of chiral colloids, which can act as model systems for chiral molecules.

Revealing structural and mechanistic details of Channelrhodopsin-2 (ChR2) is in the focus of current scientific research due to its unique ability to stimulate cell activity by light (optogenetics). Hence, ChR2 is a promising tool to revolutionize medical treatment. The aim of this work was the investigation of the light-activated mechanism of the retinylidene cation channel ChR2 on an atomistic level by means of vibrational spectroscopy.In addition to successful expression and purification of ChR2, resonance Raman and FTIR spectroscopy elucidated the structure of the chromophore binding pocket as well as the gating mechanism triggered by a single hydrogen bond between two residues (¿DC gate¿). Therefore, FTIR difference spectroscopic results were correlated with time-resolved UV/Vis spectroscopy. Flash photolysis allowed characterization of the time scale of proton release with subsequent uptake using an indicator dye.Application and modification of advanced biophysical techniques such as surface-enhanced FTIR, single-molecule force spectroscopy and doubly vibrationally-enhanced four wave mixing set the basis to obtain even deeper insights into the structure and function of membrane proteins like ChR2.

The optimization of combustion in reciprocating engines necessitates an in-depth understanding of the underlying processes as well as accurate and comprehensive physical models. In this respect, the current knowledge on the last stage of combustion in which the flame interacts with the combustion chamber walls is limited. Hence, the objective of this book is to improve the understanding of flame-wall interaction and its modelling. Using a comprehensive analysis of the existing literature on flame-wall interactions as a starting point, the quenching process in a direct-injection spark-ignition engine is investigated via a combination of highly resolved wall heat flux measurements and extensive numerical simulations in order to gain insight into the underlying physical processes. Building on the results, a consistent modelling approach is systematically derived based on the physics of flame quenching and post-flame oxidation. The resulting flame-wall interaction model is based on the G-equation combustion model and incorporates the effects of flame quenching and near-wall turbulence. Finally, the model is applied to simulate combustion in a turbulent channel flow as well as in spark-ignition engines. The results are highlighting the importance of flame-wall interactions for premixed combustion processes in engines and their prediction via simulation.

Optische Polymerfasern (POF) haben sich im Laufe der Jahre zu einem festen Bestandteil in der Kurzstreckendatenübertragung etabliert. Aufgrund der vielen Vorteile, wie einfache Installation und Handhabung, geringes Gewicht, enge Biegeradien und Kosteneffizienz, finden POF vor allem im Bereich der Industrieautomation, Automotive und Heimnetzwerken Anwendung. Die Datenübertragung über POF ist heutzutage nur auf einen Kanal zur Datenübertragung beschränkt. Daher ist die Bandbreite stark eingeschränkt. Durch die Verwendung von mehr als einem Kanal ist es möglich, die Datenrate signifikant zu erhöhen. Dies kann über das sogenannte Wavelength Division Multiplexing (WDM) Verfahren erreicht werden.Für diese Technologie sind zwei Komponenten unerlässlich: ein Multiplexer (MUX) und ein Demultiplexer (DEMUX). Der Multiplexer sammelt das Licht der verschiedenen Quellen in einer Faser, und der Demultiplexer trennt die Wellenlängen am Ende der Faser in die verschiedenen Faserausgangsanschlüsse. Um die Wellenlängen an den Ausgangsports des DEMUX zu trennen, wird ein optisches Gitter verwendet. Um den Vorteil von kostengünstigen POFs zu halten, ist es notwendig, die MUX- und DEMUX-Komponente zu vernünftigen Preisen herzustellen. Für Polymere ist das Spritzgießen heutzutage die einzige Technologie, mit der eine für den Massenmarkt taugliche Lösung realisiert werden kann. Die vorliegende Arbeit befasst sich mit der Entwicklung eines spritzgussfähigen Demultiplexers für Polymerfasern.Ein Fokus der Arbeit liegt auf der Analyse geeigneter Herstellungsmethoden für die Gitterstruktur und der Auswahl des geeigneten Materials aus dem der DEMUX gefertigt werden kann.

Ground and surface water sources in the globe are increasingly getting contaminated with increased salinity caused by global climatic changes. This increasing salinity problem is not bounded only within coastal areas, in many arid and Pacific areas inside water-bodies are also frequently getting contaminated by salinity. Nowadays, more moderate European coastal habitats are also confronted with this phenomenon. This salinity problem is considered as a potential threat to farm animal health and production. It is important to know the physiological and adaptation capacity of animals to tolerate saline water without impairing their health.This dissertation investigated the preferences and adaptation capacities of goats to saline drinking water as well as the physiological mechanisms underlying the adaptation process to increased salinity. The main focus was on the possibility to adapt the animals to increased saline concentrations in drinking water via a stepwise habituation. Blood parameters and rumen temperature were also recorded to evaluate goats' capacity in maintaining sodium balance, to detect possible health problems, and evaluate the suitability of the applied adaptation scheme.

Acid-base homeostasis is essential for human health and a variety of physiological conditions. Pathophysiological changes can result in acid-base derangements, which can be accompanied by acute and long-term metabolic disorders. Moreover, even a narrow change of blood pH still within the physiological change, e.g., a diet-induced shift towards a more acidic status, has been reported to already cause adverse health consequences. Against this background, we aimed to, by using non-invasive urinary biomarkers, examine acid-base-related physiological and epidemiological relationships of body fatness with 24-h urine pH, the potential mediatory roles of inflammatory biomarkers in the high body fat¿low urine pH relation, and the association between 24-h urinary glucocorticoid excretion and renal citrate output, as well as the prospective relationships of protein intake and dietary acid load during childhood and adolescence with adult height. All study participants were selected and data came from the DOrtmund Nutritional and Antropometric Longitudinally Designed (DONALD) Study, which includes regular examinations on dietary intake, metabolism, and growth in healthy children and adolescents until their adulthood without particular pre-specified endpoints.

Recently, the synthesis of neutral and cationic group(VI) imido/oxo alkylidene N-heterocyclic carbene (NHC) complexes that tolerate protic functional groups and aldehydes was reported. Unprecedented turnover numbers of up to 1.2 million were found for their silica-supported representatives. Some group(VI) alkylidene NHC complexes even display stability towards moisture and air. Coordination of the NHC to tungsten imido bistriflate precursor complexes, however, can lead to undesired side reactions. This work consequently aimed at the development of novel, more efficient routes to neutral and cationic tungsten imido/oxo alkylidene NHC complexes. In addition, some molybdenum imido alkylidene NHC complexes were targeted. Thereby, the scope of synthetically accessible complexes was broadened and, subsequently, their reactivity in ring-opening metathesis polymerization (ROMP) was probed. Those complexes were used as thermally latent initiators for the ROMP of dicyclopentadiene. Precise determination of the onset temperature of polymerization was achieved via monitoring with differential scanning calorimetry. Furthermore, the selectivity of novel complexes was tested for the formation of stereoregular polymers through ROMP of enantiomerically pure norbornene derivatives, which allowed for the synthesis of up to 98% trans-isotactic or cis-syndiotactic polymers depending on the steric demand of the imido and the alkoxide ligand.

Nowadays, due to the advancement and significantly rapid growth in the technology, the collection of high-dimensional data is no longer a tedious task. Regardless of considerable advances in technology over the last few decades, the analysis of high-dimensional data faces new challenges concerning interpretation and integration. One of the major problems in high-dimensional data is the occurrence of missing values. The problem is in particular hard to handle when the distributional forms of the variables are different or the variables are measured on different measurement scales (e.g. binary, multi-categorical, continuous, etc.). Whatever the reason, missing data may occur in all areas of applied research.The inadequate handling of missing values may lead to biased results and incorrect inference. The standard statistical techniques for analyzing the data require complete cases without any missing observations. The deletion of the cases with missing information to obtain complete data will not only cause the loss of important information but can also affect inferences. In this dissertation, different imputation techniques using nearest neighbors are developed to address the missing data issues in high-dimensional as well as low dimensional data structures.

This research work is on Short- and Long-term Stability of a 100% Renewable Autonomous Power System for a Typical Geographical Region. It is concerned with understanding, modelling, analysing and mitigating power system stability problems associated with 100 percent renewable electrical power system. The complexity of power systems is continually increasing because of the growth in asynchronous interconnections and use of new power electronic based technologies for solar and wind power integrations. At the same time, regulatory constraints have forced utilities to increase the renewable energy share on the power systems. This research mainly deals with maximizing the Non-Conventional Renewable Energy (NCRE) share in the power system. Implementation of 100 percent renewable electric power system is no longer a myth. However, the system requires a large energy storage capacity for full supply with renewable energy in the electricity sector and new large scale of synchronous inertia shall be added to the system for frequency stability. Furthermore, necessary measures have to be taken for maintaining power system oscillations and damping which occur due to frequent power disturbances from wind and solar energy sources. However, the implementation of 100 percent renewable electrical power system depends on the many other things such as the financial capability, resources availability, etc.

This thesis discusses potential pathways and driving forces for lipid transport through crystalline fat suspensions such as chocolate. Observation of macroscopic migration indicated that structure plays a major role. Microtomography images of chocolates confirmed the presence of voids, which might act as preferred pathway. Small angle X-ray scattering manifested that lipids migrate through pores in the short-term and the fat phase in the long-term. Migration rates were approximated with a model based on viscous flow driven by capillary pressure. More information on material properties is needed to verify that model.Diese Arbeit diskutiert potentielle Wege und Ursachen für den Transport von Lipiden durch Fettsuspensionen wie Schokolade. Makroskopische Untersuchungen zeigten, dass die Struktur den Transport stark beeinflusst. Mikrotomografieaufnahmen und Kleinwinkelstreuung bestätigten ein Vorhandensein von Hohlräumen in Schokolade und deren Komponenten, die bevorzugte Wege für den Lipidtransport sein könnten. Migrationsgeschwindigkeiten wurden mit einem Modell basierend auf der Darcy und Lucas-Washburn-Gleichung berechnet. Genaue Kenntnisse zu den Materialeigenschaften sind essenziell, um dieses Modell zu bestätigen.

I owe a debt of gratitude ¯rst and foremost to my supervisor, Prof. Markus Leippold.From the very beginning of my dissertation, Markus was a demanding and highlymotivating advisor who always believed in the potential value of my research topic.I thank him for his invaluable support. I am also deeply obliged to Prof. HansGeiger, co-supervisor with Prof. Leippold, who gave me the opportunity to workby his side and bene¯t from the exceptional research network at the Swiss BankingInstitute. I am indebted to Prof. Roger Bey, who invited me to spend a full academicyear at the Finance Department of the University of Tulsa, where I encountered avery inspiring environment that allowed me to devote a great deal of time on myresearch. Furthermore, I thank Florian Eugster for careful proofreading and manyfruitful discussions on the empirical part of the thesis. I thank my brother SebastienRohner for designing the cover page and Lenore Hietkamp for excellent editorialassistance. I am also grateful to Blanca who supported me during all stages of thethesis with so much energy, fortitude and love. Finally, I o®er my gratitude to myparents Beatrice and Roland Rohner for their continuous encouragement throughoutmy life; to them I owe everything I have achieved so far.

In classical optimization theory, it is usually assumed that there is a single objective that is to be optimized: Find the cheapest solution, or the quickest, or the one of highest quality. In practice, however, we are often looking for solution that are both cheap, and quick, and of good quality. Usually these multiple criteria are in conflict ¿ there won¿t be a solution that is optimal in all objectives. Multicriteria optimization therefore studies extended solution concepts. One of these concepts is the so-called reference point method, including the special case of compromise programming. The thesis The Power of Compromise presents a comprehensive theoretical analysis of these concepts, and demonstrates their power: The ability to compute or at least approximate reference point solutions is (in the complexity theoretical sense) equivalent to the ability to compute, respectively approximate, the set of all Pareto optimal (i.e., non-dominated) solutions. The theoretical results are complemented by two examples of practical applications of the reference point method.

This work represents first attempts at delineating individual tree crowns in Zagros areausing QuickBird data. The Zagros forest zone is the second important forest region ofIran with high ecological and socio-economic values and provides services to asignificant parts of Iran¿s human population. These forests are experiencing rapiddegradation due to environmental and human impact at local scale. To efficiently managethese forests for conservation and other ecological purposes forest managers demand tohave detailed information on forest composition and structure. Because of the wide extentas well as spatial structure of these forests, extracting the required information by meansof traditional field based methods is time-consuming and costly, whilst application oflow-medium resolution satellite imagery will not yield accurate and reliable results. It is,therefore, critically important to investigate the new advanced spaceborne remote sensingtechnologies that permit to extract detail information. Very high spatial resolution satelliteimagery can supply forest management planning with individual tree based information,which was unfeasible to accomplish with the same efficiency and precision withmoderate-resolution satellite imagery. Application to the Zagros forests face to the uniquetechnical challenges including high variability in crown shape and size, strong effects ofthe background reflectance, and varying age and health condition.The capabilities of QuickBird imagery examined with the data acquired over the Oakforest site on the South West of Iran. Different image fusion techniques were applied toexploit optimal spatial and spectral information of this imagery. The core technicalobjective was selecting a fusion method with high fidelity of spectral and spatialinformation. Quality assessment of fused images showed that the PCA method performsbetter than the others in this study.

Semidefinite Optimization has attracted the attention of many researchers over the last twenty years. It has nowadays a huge variety of applications in such different fields as Control, Structural Design, Statistics, or in the relaxation of hard combinatorial problems. In this thesis, we focus on the practical tractability of large-scale semidefinite optimization problems. From a theoretical point of view, these problems can be solved by polynomial-time Interior-Point methods approximately. The complexity estimate of Interior-Point methods grows logarithmically in the inverse of the solution accuracy, but with the order 3.5 in both the matrix size and the number of constraints. The later property prohibits the resolution of large-scale problems in practice.In this thesis, we present new approaches based on advanced First-Order methods such as Smoothing Techniques and Mirror-Prox algorithms for solving structured large-scale semidefinite optimization problems up to a moderate accuracy. These methods require a very specific problem format. However, generic semidefinite optimization problems do not comply with these requirements. In a preliminary step, we recast slightly structured semidefinite optimization problems in an alternative form to which these methods are applicable, namely as matrix saddle-point problems. The final methods have a complexity result that depends linearly in both the number of constraints and the inverse of the target accuracy.Smoothing Techniques constitute a two-stage procedure: we derive a smooth approximation of the objective function at first and apply an optimal First-Order method to the adapted problem afterwards. We present a refined version of this optimal First-Order method in this thesis. The worst-case complexity result for this modified scheme is of the same order as for the original method. However, numerical results show that this alternative scheme needs much less iterations than its original counterpart to find an approximate solution in practice. Using this refined version of the optimal First-Order method in Smoothing Techniques, we are able to solve randomly generated matrix saddle-point problems involving a hundred matrices of size 12¿800 x 12¿800 up to an absolute accuracy of 0.0012 in about four hours.Smoothing Techniques and Mirror-Prox methods require the computation of one or two matrix exponentials at every iteration when applied to the matrix saddle-point problems obtained from the above transformation step. Using standard techniques, the efficiency estimate for the exponentiation of a symmetric matrix grows cubically in the size of the matrix. Clearly, this operation limits the class of problems that can be solved by Smoothing Techniques and Mirror-Prox methods in practice. We present a randomized Mirror-Prox method where we replace the exact matrix exponential by a stochastic approximation. This randomized method outperforms all its competitors with respect to the theoretical complexity estimate on a significant class of large-scale matrix saddle-point problems. Furthermore, we show numerical results where the randomized method needs only about 58% of the CPU time of the deterministic counterpart for solving approximately randomly generated matrix saddle-point problems with a hundred matrices of size 800 × 800.As a side result of this thesis, we show that the Hedge algorithm ¿ a method that is heavily used in Theoretical Computer Science ¿ can be interpreted as a Dual Averaging scheme. The embedding of the Hedge algorithm in the framework of Dual Averaging schemes allows us to derive three new versions of this algorithm. The efficiency guarantees of these modified Hedge algorithms are at least as good as, sometimes even better than, the complexity estimates of the original method. We present numerical experiments where the refined methods significantly outperform their vanilla counterpart.

This thesis presents the major viruses affecting three cultivars in Colombia and how experimental approaches in serology, molecular biology, and bioinformatics can be adapted to create a protocol that could be applied for physalis, passionfruit, ornamental rose, and eventually other crops.Selection of farms was carried out based on size and economic importance. Initial visual plant symptom appraisal led collection of 370 samples from 20 farms. Literature review guided the selection of antibodies of known viruses for initial ELISA testing. Thereafter NGS was carried out to discover further known and novel viruses in the cultivars. Various experiments were carried out on different samples including biotest inoculation, ELISA, RT-PCR, and NGS.Reliable and practical diagnostic tools like these could be developed for the most important viruses leading to a national agricultural certification program that could be established in a common project between German and Colombian universities, the Colombian Agricultural Institute (ICA), the Colombian Corporation of Agricultural Investigation (AGROSAVIA), and the International Center for Tropical Agriculture (CIAT).

Bochum University of Applied Sciences has identified the central transformation topics ofsustainability and digitalisation as a key goal and anchored them in its strategy. In severalstudy programmes, students are already being prepared and qualified as future expertsfor their tasks as agents of change in the transformation process. The importance of digitalisation for solving future sustainabilitychallenges is clearly becoming the dominant factor. In its report Our Common Digital Future,the Advisory Council on Global Change (WBGU) emphasises that digitalisation mustbe designed in such a way that it can serve as a lever and support for the Great Transformationtowards sustainability and can be synchronised with it.In this context, technological approaches and use cases from the areas of blockchain anddecentralized finance are prominently discussed in the public debate and are still controversialwith regard to their contribution to sustainable development.

Climate change has become one of the most significant challenges humanity faces. Asgreenhouse gas emissions continue to rise, not only will natural disasters strike considerablymore frequently and severely, but whole swaths of land will become uninhabitableand infertile as farmland. It is apparent that long-term approaches like reaching net-zerowith new technologies are important, but so are short-term measures to avoid tippingpoints and passing points of no return. The transport sector accounts for nearly a quarter(23%) of energy related-emissions, and 40-60% of these transport-related emissionsstem from commuting and business traveling. One short-term approach to lower transportemissions is ridesharing: When two or more commuters team up, significant emissionscan be saved. As a result, business trip ridesharing (BTRS), the sharing of individualvehicles for commuting and business trips among employees, has gained increased attentionfrom organizations and academia alike. BTRS shares similar adoption challengeslike ridesharing and shared-mobility overall: From individuals' prevalence to solving thematching and allocation problem of shared resources. This thesis investigates the role that Green Information Systems (Green IS) can play tosupport BTRS adoption.

Elizaphan James Oburu Rao was born in Kisumu,Kenya in 1974. He holds a PhD in AgriculturalEconomics from University of Goettingen wherehe worked as a research associate at the Chairof International Food Economics and RuralDevelopment. The author holds a Masters degreein Agricultural Economics from University ofHohenheim, Germany, a Masters degree inInternational Cooperation Policy from Ritsu-meikan ¿ Asia Pacifi c University, Japan and aBachelors degree in AgriculturalEconomics from Egerton University, Kenya.This book presents an analysis of the ruraldevelopment implications of emerging high-valuechains in developing countries. The study uses datafrom a household survey of vegetable producers in Kenya and appliesinnovative analytical methods to evaluate impacts of farmer participationin high-value food chains on farm productivity and technical effi ciency.Impacts of supply chain modernization on household income and poverty aswell as impacts on agricultural labor markets are also analyzed.