889 resultados para Driving Forces
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Today industries and commerce in Ghana are facing enormous energy challenge. The pressure is on for industries to reduce energy consumption, lower carbon emissions and provide se-cured power supply. Industrial electric motor energy efficiency improvement is one of the most important tools to reduce global warming threat and reduce electricity bills. In order to develop a strategic industrial energy efficiency policy, it is therefore necessary to study the barriers that inhibit the implementation of cost – effective energy efficiency measures and the driving forces that promote the implementation. The aim of this thesis is to analyse the energy consumption pattern of electric motors, study factors that promote or inhibit energy efficiency improvements in EMDS and provide cost – effective solutions that improve energy efficiency to bridge the existing energy efficiency gap in the surveyed industries. The results from this thesis has revealed that, the existence of low energy efficiency in motor-driven systems in the surveyed industries were due to poor maintenance practices, absence of standards, power quality issues, lack of access to capital and limited awareness to the im-portance of energy efficiency improvements in EMDS. However, based on the results pre-sented in this thesis, a policy approach towards industrial SMEs should primarily include dis-counted or free energy audit in providing the industries with the necessary information on potential energy efficiency measures, practice best motor management programmes and estab-lish a minimum energy performance standard (MEPS) for motors imported into the country. The thesis has also shown that education and capacity development programmes, financial incentives and system optimization are effective means to promote energy efficiency in elec-tric motor – driven systems in industrial SMEs in Ghana
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‘The Father of Canadian Transportation’ is a term commonly associated with William Hamilton Merritt. Although he is most known for being one of the driving forces behind the building of the first Welland Canal, he was many things throughout his life; a soldier, merchant, promoter, entrepreneur and politician to name a few. Born on July 3, 1793 at Bedford, Westchester County, N.Y. to Thomas Merritt and Mary Hamilton, Merritt’s family relocated to Canada shortly after in 1796. The move came after Merritt’s father petitioned John Graves Simcoe for land in Upper Canada after serving under him in the Queen’s Rangers during the American Revolution. The family quickly settled into their life at Twelve Mile Creek in St. Catharines. Merritt’s father became sheriff of Lincoln County in 1803 while Merritt began his education in mathematics and surveying. After some brief travel and further education Merritt returned to Lincoln County, in 1809 to help farm his father’s land and open a general store. While a farmer and merchant, Merritt turned his attention to military endeavours. A short time after being commissioned as a Lieutenant in the Lincoln militia, the War of 1812 broke out. Fulfilling his duty, Merritt fought in the Battle of Queenston Heights in October of 1812, and numerous small battles until the Battle of Lundy’s Lane in July 1814. It was here that Merritt was captured and held in Cheshire, Massachusetts until the war ended. Arriving back in the St. Catharines area upon his release, Merritt returned to being a merchant, as well as becoming a surveyor and mill owner. Some historians hypothesize that the need to draw water to his mill was how the idea of the Welland Canals was born. Beginning with a plan to connect the Welland River with the Twelve mile creek quickly developed into a connection between the Lakes Erie and Ontario. Its main purpose was to improve the St. Lawrence transportation system and provide a convenient way to transport goods without having to go through the Niagara Falls portage. The plan was set in motion in 1818, but most living in Queenston and Niagara were not happy with it as it would drive business away from them. Along with the opposition came financial and political restraints. Despite these factors Merritt pushed on and the Welland Canal Company was chartered by the Upper Canadian Assembly on January 19, 1824. The first sod was turned on November 30, 1824 almost a year after the initial chartering. Many difficulties arose during the building of the canal including financial, physical, and geographic restrictions. Despite the difficulties two schooners passed through the canal on November 30, 1829. Throughout the next four years continual work was done on the canal as it expended and was modified to better accommodate large ships. After his canal was underway Merritt took a more active role in the political arena, where he served in various positions throughout Upper Canada. In 1851, Merritt withdrew from the Executive Council for numerous reasons, one of which being that pubic interest had diverted from the canals to railways. Merritt tried his hand at other public works outside transportation and trade. He looked into building a lunatic asylum, worked on behalf of War of 1812 veterans, aided in building Brock’s monument, established schools, aided refugee slaves from the U.S. and tried to establish a National Archives among many other feats. He was described by some as having “policy too liberal – conceptions too vast – views too comprehensive to be comprehensible by all”, but he still made a great difference in the society in which he lived. After his great contributions, Merritt died aboard a ship in the Cornwall canal on July 5, 1862. Dictionary of Canadian Biography Online http://www.biographi.ca/EN/ShowBio.asp?BioId=38719 retrieved October 2006 Today numerous groups carry on the legacy of Merritt and the canals both in the past and present. One such group is the Welland Canals Foundation. They describe themselves as: “. . . a volunteer organization which strives to promote the importance of the present and past Welland Canals, and to preserve their history and heritage. The Foundation began in 1980 and carries on events like William Hamilton Merritt Day. The group has strongly supported the Welland Canals Parkway initiative and numerous other activities”. The Welland Canals Foundation does not work alone. They have help from other local groups such as the St. Catharines Historical Society. The Society’s main objective is to increase knowledge and appreciation of the historical aspects of St. Catharines and vicinity, such as the Welland Canals. http://www.niagara.com/~dmdorey/hssc/dec2000.html - retrieved Oct. 2006 http://www.niagara.com/~dmdorey/hssc/feb2000.html - retrieved Oct. 2006
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The relationships between vine water status, soil texture, and vine size were observed in four Niagara, Ontario Pinot noir vineyards in 2008 and 2009. The vineyards were divided into water status zones using geographic information systems (GIS) software to map the seasonal mean midday leaf water potential (,P), and dormant pruning shoot weights following the 2008 season. Fruit was harvested from all sentinel vines, bulked by water status zones and made into wine. Sensory analysis included a multidimensional sorting (MDS) task and descriptive analysis (DA) of the 2008 wines. Airborne multispectral images, with a spatial resolution of 38 cm, were captured four times in 2008 and three times in 2009, with the final flights around veraison. A semi-automatic process was developed to extract NDVI from the images, and a masking procedure was identified to create a vine-only NDVI image. 2008 and 2009 were cooler and wetter than mean years, and the range of water status zones was narrow. Yield per vine, vine size, anthocyanins and phenols were the least consistent variables. Divided by water status or vine size, there were no variables with differences between zones in all four vineyards in either year. Wines were not different between water status zones in any chemical analysis, and HPLC revealed that there were no differences in individual anthocyanins or phenolic compounds between water status zones within the vineyard sites. There were some notable correlations between vineyard and grape composition variables, and spatial trends were observed to be qualitatively related for many of the variables. The MDS task revealed that wines from each vineyard were more affected by random fermentation effects than water status effects. This was confirmed by the DA; there were no differences between wines from the water status zones within vineyard sites for any attribute. Remotely sensed NDVI (normalized difference vegetation index) correlated reasonably well with a number of grape composition variables, as well as soil type. Resampling to a lower spatial resolution did not appreciably affect the strength of correlations, and corresponded to the information contained in the masked images, while maintaining the range of values of NDVI. This study showed that in cool climates, there is the potential for using precision viticulture techniques to understand the variability in vineyards, but the variable weather presents a challenge for understanding the driving forces of that variability.
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Résumé Depuis le début des années 1990, la recherche sur le développement régional a pris une importance considérable dans les disciplines de l’économie et de la géographie dans la plupart des pays. De nombreuses études ont été consacrées à ce sujet et l’on constate une approche analytique de plus en plus sophistiquée. Que les économies pauvres ont tendance à converger vers les pays riches, ou bien à diverger au fil du temps est une question qui a attiré l'attention des décideurs et des universitaires depuis quelques décennies. Convergence ou de divergence économique est un sujet d'intérêt et de débat, non seulement pour valider ou non les deux modèles principaux de croissance qui sont considérés comme concurrent (l’approche néo-classique et celle des approches de croissance endogène), mais aussi pour ses implications pour les publiques politiques. En se basant sur une analyse des politiques de développement régional et des analyses statistiques de la convergence et des disparités régionales, les objectifs de cette thèse sont de tenter de fournir une explication des différents processus et des modèles de développement économique régional poursuivis dans le cas de territoires immenses en utilisant le Canada et la Chine comme études de cas, d'entreprendre une analyse des différents facteurs et des forces motrices qui sous-tendent le développement régional dans ces deux pays, et d'explorer à la fois les réussites et les échecs apparents dans les politiques de développement régional en comparant et contrastant les expériences de développement régional et les modèles de ces deux pays. A fin d'atteindre cet objectif, la recherche utilise une approche multi-scalaire et des méthodes de mesure multidimensionnelle dans le cadre des analyses sur les disparités « régionales » entre les macro régions (sous-ensembles de provinces) des deux pays, des provinces et des régions urbaines sélectionnées, dans le but ultime d’identifier des problèmes existants en termes de développement régional et de pouvoir proposer des solutions. Les étapes principales de la recherche sont : 1. La cueillette des données statistiques pour le Canada et la Chine (incluant les provinces de Québec et de Xinjiang) pour une gamme d’indicateurs (voir ci-dessous). 2. D’entreprendre une analyse de chaque dimension dans les deux juridictions: Population (p.ex. composition, structure, changement); Ressources (p. ex. utilisation, exploitation de l’énergie); Environnement (p.ex. la pollution); et le Développement socioéconomique (p.ex. le développement et la transformation des secteurs clé, et les modèles de développement rural et urbain), et les disparités changeantes par rapport à ces dimensions. 3. La définition d’une typologie de différents types de région en fonction de leurs trajectoires de développement, ce qui servira pour critiquer l’hypothèse centre-périphérie. 4. Le choix d’une région métropolitaine dans chaque juridiction (province). 5. D’entreprendre une analyse temporelle des événements clé (politiques, investissements) dans chaque région et les facteurs impliqués dans chaque événement, en utilisant l’information documentaire générale et des agences institutionnelles impliqués actuellement et dans un passée récent. Cette étude a tenté d'expliquer les schémas et les processus des deux économies, ainsi que la présentation d'études de cas qui illustrent et examinent les différences dans les deux économies à partir de l’échelle nationale jusqu’au niveau régional et provincial et aussi pour certaines zones urbaines. Cette étude a essayé de répondre aux questions de recherche comme: Est-il vrai que les pays avec des plus grandes territoires sont associés avec des plus grandes disparités interrégionales? Quel est le résultat des comparaisons entre pays développés et pays en développement? Quels sont les facteurs les plus importants dans le développement économique de vastes territoires dans les pays développés et pays en développement? Quel est le mécanisme de convergence et de divergence dans les pays développés et, respectivement, les pays en développement? Dans l'introduction à la thèse, le cadre général de l'étude est présenté, suivie dans le chapitre 1 d'une discussion sur les théories et les concepts utilisés dans la littérature théorique principale qui est pertinent à l'étude. Le chapitre 2 décrit la méthodologie de recherche. Le chapitre 3 présente une vue d'ensemble des politiques de développement économique régional et les programmes du Canada et de la Chine dans des périodes différentes à différentes échelles. Au chapitre 4, la convergence des deux pays à l'échelle nationale et la convergence provinciale pour chaque pays sont examinés en utilisant différentes méthodes de mesure telles que les méthodes traditionnelles, la convergence bêta et la convergence sigma. Dans le chapitre le plus complexe, le chapitre 5, les analyses comparatives sont présentées à l'aide de données statistiques, à partir des analyses des cas régionaux et provinciaux retenus des deux pays. Au chapitre 6, ces dispositions sont complétées par une analyse des régions urbaines choisies, qui permet également des aperçus sur les régions les plus périphériques. Dans la recherche proposée pour cette thèse, la politique, la population, le revenu, l'emploi, la composition industrielle, l'investissement, le commerce et le facteur de la migration sont également pris en compte comme facteurs importants de l'analyse régionale compte tenu de la superficie du territoire des deux pays et les différences de population entre eux. Cette thèse a évalué dans quelle mesure les politiques gouvernementales ont réussi à induire la convergence régionale ou ont encore ont creusé davantage les disparités régionales, ce qui implique nécessairement une évaluation de la durabilité des patrons et des programmes de développement régional. Cette étude a également mis l'accent sur les disparités régionales et la politique de développement régional, les comparaisons entre pays, pour mesurer la convergence entre les pays et entre les régions, y compris l'analyse spatiale, d'identifier les facteurs les plus actifs tels que la population, les ressources, la politique, l'urbanisation, les migrations, l'ouverture économique et leurs différents rôles dans le développement économique de ces grands territoires (au Canada et Chine). Les résultats empiriques et les processus de convergence et de divergence offrent un cadre intéressant pour l'examen de la trajectoire de développement régionales et les disparités régionales dans les deux économies. L'approche adoptée a révélé les différentes mosaïques complexes du développement régional dans les deux pays. Les résultats de cette étude ont démontré que la disparité en termes de revenu régional est une réalité dans chaque zone géographique, et que les causes sont nombreuses et complexes. Les deux économies ont certains parallèles dans la mise en œuvre des politiques de développement économique régional, mais il existe des différences importantes aussi et elles se sont développées à différentes vitesses. Les deux économies se sont développées depuis la Seconde Guerre mondiale, mais la Chine a connu une croissance rapide que le Canada comme témoignent de nombreux indicateurs depuis 1980. Cependant, la Chine est maintenant confrontée à un certain nombre de problèmes économiques et sociaux, y compris les disparités régionales marquées, un fossé toujours croissant entre les revenus ruraux et urbains, une population vieillissante, le chômage, la pauvreté et la dégradation rapide de l'environnement avec toujours plus de demandes en énergie. Le développement économique régional en Chine est plus déséquilibré. Le Canada accuse un degré de disparités régionales et provinciales moins important que la Chine. Dans les cas provinciaux, il existe d'importantes différences et de disparités dans la structure économique et spatiale du Québec et du Xinjiang. Les disparités infra provinciales sont plus grandes que celles à l’échelle des provinces et des grandes régions (des sous-ensembles de provinces). Les mécanismes de convergence et de divergence dans les deux pays sont différents. Les résultats empiriques et les processus de convergence et de divergence offrent un cadre intéressant pour l'examen de la trajectoire de développement régionale et les disparités régionales dans les deux économies. Cette étude démontre également que l'urbanisation (les métropoles et les villes) s’avère être le facteur le plus actif et contribue à l'économie régionale dans ces grands territoires. L'ouverture a joué un rôle important dans les économies des deux pays. La migration est un facteur majeur dans la stimulation de l'économie des deux pays mais de façons différentes. Les résultats empiriques démontrent que les disparités régionales ne peuvent pas être évitées et elles existent presque partout. Il n'y a pas une formule universelle et de politiques spécifiques sont de mise pour chaque région. Mais il semble possible pour les décideurs politiques nationaux et régionaux d’essayer de maintenir l'écart à une échelle raisonnable pour éviter l'instabilité sociale.
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L’objectif général de cette recherche doctorale est l’étude des déterminants de l’intégration pédagogique des technologies de l’information et de la communication (TIC) par les professeurs à l’Université de Ouagadougou (UO). Cela nous a conduit à étudier respectivement les compétences technologiques des professeurs, les facteurs de résistance contraignant l’intégration pédagogique des TIC par ces professeurs, l’acceptation et les usages spécifiques des TIC par les professeurs. Ce travail s’est bâti autour des concepts théoriques sur les usages éducatifs des TIC, les compétences technopédagogiques, les facteurs de résistance, l’acceptation des TIC et l’intégration pédagogique des TIC. Ces concepts se sont inscrits dans les cadres d’analyses des modèles d’intégration des TIC par les professeurs et des modèles d’acceptation et d’utilisation d’une nouvelle technologie. La stratégie d’analyse des données s’est construite autour des approches descriptives et analytiques notamment au moyen de l’utilisation de la psychométrie et/ou de l’économétrie des modèles à variables dépendantes limitées. Utilisant la recherche quantitative, le recrutement de 82 professeurs par avis de consentement à participer, a permis de collecter les données sur la base de questionnaires dont la majeure partie est bâtie autour de questions à échelle de Likert. L’étude des compétences technologiques des professeurs a permis d’une part, de dresser un portrait des usages des TIC par les professeurs. En effet, les usages les plus répandus des TIC dans cette université sont les logiciels de bureautique, les logiciels de messagerie électronique et de navigation dans Internet. Elle a aussi permis de faire un portrait des compétences technologiques des professeurs. Ceux-ci utilisent à la fois plusieurs logiciels et reconnaissent l’importance des TIC pour leurs tâches pédagogiques et de recherche même si leur degré de maîtrise perçue sur certaines des applications télématiques reste à des niveaux très bas. Par rapport à certaines compétences comme celles destinées à exploiter les TIC dans des situations de communication et de collaboration et celles destinée à rechercher et à traiter des informations à l’aide des TIC, les niveaux de maîtrise par les professeurs de ces compétences ont été très élevés. Les professeurs ont eu des niveaux de maîtrise très faibles sur les compétences destinées à créer des situations d’apprentissage à l’aide des TIC et sur celles destinées à développer et à diffuser des ressources d’apprentissage à l’aide des TIC malgré la grande importance que ceux-ci ont accordée à ces compétences avancées essentielles pour une intégration efficace et efficiente des TIC à leurs pratiques pédagogiques. L’étude des facteurs de résistance a permis d’ériger une typologie de ces facteurs. Ces facteurs vont des contraintes matérielles et infrastructurelles à celles liées aux compétences informatiques et à des contraintes liées à la motivation et à l’engagement personnel des professeurs, facteurs pouvant susciter des comportements de refus de la technologie. Ces facteurs sont entre autres, la compatibilité des TIC d’avec les tâches pédagogiques et de recherche des professeurs, l’utilité perçue des TIC pour les activités pédagogiques et de recherche, les facilités d’utilisation des TIC et la motivation ou l’engagement personnel des professeurs aux usages des TIC. Il y a aussi les coûts engendrés par l’accès aux TIC et le manque de soutien et d’assistance technique au plan institutionnel qui se sont révelés enfreindre le développement de ces usages parmi les professeurs. Les estimations des déterminants de l’acceptation et des usages éducatifs des TIC par les professeurs ont montré que c’est surtout « l’intention comportementale » d’aller aux TIC des professeurs, « l’expérience d’Internet » qui affectent positivement les usages éducatifs des TIC. Les « conditions de facilitation » qui représentent non seulement la qualité de l’infrastructure technologique, mais aussi l’existence d’un soutien institutionnel aux usages des TIC, ont affecté négativement ces usages. Des éléments de recommandation issus de ce travail s’orientent vers la formation des professeurs sur des compétences précises identifiées, l’amélioration de la qualité de l’infrastructure technologique existante, la création d’un logithèque, la mise en œuvre d’incitations institutionnelles adéquates telles que l’assistance technique régulière aux professeurs, l’allègement des volumes horaires statutaires des professeurs novateurs, la reconnaissance des efforts déjà réalisés par ces novateurs en matière d’usages éducatifs des TIC dans leur institution.
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La recherche, construction et révision de l’identité nationale ont très longtemps constitué les éléments propulseurs de la production littéraire et intellectuelle de Porto Rico. Pourtant vers le milieu des années 90, un nouveau consensus émerge entre les écrivains qui revendiquent massivement la fin de la littérature en tant que lieu d’où forger la conscience nationale et refuse le leadership intellectuel qui avait jusqu’alors définit le travail littéraire. Les auteurs qui commencent à se manifester à ce moment se désintéressent du nationalisme comme thème littéraire. Le militantisme politique et la volonté de confrontation, modes représentationnels caractéristiques de la génération antérieure, disparaissent pour laisser place à une écriture exploratoire, centrée sur ses propres procédés, et apparemment apolitique. Une telle perte d’ancrages nationaux et territoriaux est significative de la conscience exacerbée que possèdent ces écrivains de la complexité des dynamiques culturelles qui régissent le monde postmoderne et globalisé, ainsi que de la « valeur » et de la position « marginale » qu’on leur attribue dans l’écologie mass-médiatique culturelle actuelle. La production narrative de Mayra Santos-Febres est paradigmatique de ces changements. J’aborde dans son écriture une série de dispositifs métalittéraires, autoréflexifs, « érographiques », et historiographiques qui, bien qu’ils résistent à une catégorisation homogène, démontrent un même intérêt pour des phénomènes interstitiels. En me basant sur les concepts de liminalité, principalement depuis la perspective de Victor Turner et d’écriture auto-réflexive (Patricia Waugh, Linda Hutcheon), j’analyse le positionnement liminal qu’assume Santos-Febres dans la structure culturelle globalisée actuelle, et la façon dont sa prise de position, également liminale, c’est-à-dire, sa prise de parole et son engagement se traduisent par un rapprochement narcissique à l’exercice littéraire autant dans les formes qu’elle crée qu’au niveau sémantique, narratif et discursif. Le premier chapitre analyse les contes « Dilcia M. » et « Acto de Fe » (Pez de vidrio) comme témoignages de l’érosion du patriotisme et militantisme antérieur; « La escritora» (Pez de vidrio) qui marque pour l’auteure un passage vers une esthétique centrée sus ses propres procédés créatifs; et le roman Cualquier miércoles soy tuya qui dramatise le positionnement assumé par les écrivains dans la chaine culturelle globalisée actuelle. Le second chapitre aborde la configuration des corps, espaces urbains et de l’écriture dans El cuerpo correcto qui, à travers une exubérance sexuelle/textuelle, projette des variantes réactualisées de la traditionnelle dichotomie corps/écriture. Le troisième chapitre se penche sur la configuration du travesti dans Sirena Selena vestida de pena. J’y propose de voir le travestisme, le boléro et l’écriture comme un triple exercice métalittéraire. Le dernier chapitre aborde le procédé de re-signification littéraire des images sédimentées de subordination et d’infériorité de sujet « noir ». Nuestra Señora de la Noche se penche sur la re-signification de l’hyper-sexualisation et « exotisation » qui a cimenté la construction de « l’immoralité » de la femme noire. Fe en disfraz aborde le sadomasochisme comme espace de re-signification des schèmes de domination et soumission inscrits dans l’histoire esclavagiste de Porto Rico et du trauma qui origine, et subsiste, d’une telle hiérarchie.
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This thesis entitled seasonal and interannual variability of sea level and associated surface meteorological parameters at cochin.The interesting aspect of studying sea level variability on different time scales can be attributed to the diversity of its applications.Study of tides could perhaps be the oldest branch of physical oceanography.The thesis is presented in seven chapters. The first chapter gives, apart from a general introduction, a survey of literature on sea level variability on different time scales - tidal, seasonal and interannual (geological scales excluded), with particular emphasis on the work carried out in the Indian waters. The second chapter is devoted to the study of observed tides at Cochin on seasonal and interannual time scales using hourly water level data for the period 1988-1993. The third chapter describes the long-term climatology of some important surface oceanographic and meteorological parameters (at Cochin) which are supposed to affect the sea level. The fourth chapter addresses the problem of seasonal forecasting of the meteorological and oceanographic parameters at Cochin using autoregressive, sinusoidal and exponentially weighted moving average techniques and testing their accuracy with the observed data for the period 1991-1993. The fifth chapter describes the seasonal cycles of sea level and the driving forces at 16 stations along the Indian subcontinent. It also addresses the observed interannual variability of sea level at 15 stations using available multi-annual data sets. The sixth chapter deals with the problem of coastal trapped waves between Cochin and Beypore off the Kerala coast using sea level and atmospheric pressure data sets for the year 1977. The seventh and the last chapter contains the summary and conclusions and future outlook based on this study.
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Die sogenannte natürliche Lüftung - Lüftung infolge Temperatur- und Windeinfluss - über geöffnete Fenster und Türen ist im Wohnbereich noch immer die häufigste Form des Lüftens. Die Wirkung des Lüftens wird einerseits von den baulichen Gegebenheiten, z.B. der Fenstergröße, Öffnungsfläche und Laibungstiefe sowie andererseits durch den Nutzer, der z.B. eine Gardine oder Rollos anbringt, beeinflusst. Über den genauen Einfluss von verschiedenen Faktoren auf den Luftwechsel existieren zur Zeit noch keine gesicherten Erkenntnisse. Die Kenntnis des Luftwechsels ist jedoch für die Planung und Ausführung von Gebäuden in Hinblick auf das energiesparende Bauen sowie unter bauphysikalischen und hygienischen Aspekten wichtig. Der Einsatz von Dreh-Kippfenstern sowie das Lüften über die Kippstellung ist in Deutschland üblich, so dass die Bestimmung des Luftwechsels über Kippfenster von großem Interesse ist. Ziel dieser Arbeit ist es, den thermisch induzierten Luftwechsel über ein Kippfenster unter Berücksichtigung verschiedener Randbedingungen zu beschreiben. Hierbei werden Variationen der Kippweite, Laibungs- und Heizungsanordnung berücksichtigt. Die Arbeit gliedert sich in drei Teile: im ersten Teil werden messtechnische Untersuchungen durchgeführt, im zweiten Teil exemplarisch einige messtechnisch untersuchten Varianten mit CFD simuliert und im dritten Teil ein verbesserter Modellansatz zur Beschreibung des Luftwechsels aus den Messwerten abgeleitet. Die messtechnischen Untersuchungen bei einer Kippweite von 10 cm zeigen, dass bei dem Vorhandensein einer raumseitigen Laibung oder einem unterhalb des Fensters angeordneten Heizkörpers mit einer Reduktion des Volumenstroms von rund 20 Prozent gegenüber einem Fenster ohne Laibung bzw. ohne Heizkörper gerechnet werden muss. Die Kombination von raumseitiger Laibung und Heizung vermindert das Luftwechselpotential um ca. 40 Prozent. Simuliert wird die Variante ohne Laibung und ohne Heizung für die Kippweiten 6 cm und 10 cm. Die Ergebnisse der mit CFD simulierten Tracergas-Messung weisen für beide Kippweiten im Mittel rund 13 Prozent höhere Zuluftvolumenströme im Vergleich zu den Messwerten auf. Die eigenen Messdaten bilden die Grundlage für die Anpassung eines Rechenmodells. Werden vor Ort die lichte Fensterhöhe und -breite, die Kippweite, die Rahmen- und Laibungstiefe sowie die Abstände der Laibung zum Flügelrahmen gemessen, kann die Öffnungsfläche in Abhängigkeit von der Einbausituation bestimmt werden. Der Einfluss der Heizung - bei einer Anordnung unterhalb des Fensters - wird über den entsprechenden Cd-Wert berücksichtigt.
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Landwirtschaft spielt eine zentrale Rolle im Erdsystem. Sie trägt durch die Emission von CO2, CH4 und N2O zum Treibhauseffekt bei, kann Bodendegradation und Eutrophierung verursachen, regionale Wasserkreisläufe verändern und wird außerdem stark vom Klimawandel betroffen sein. Da all diese Prozesse durch die zugrunde liegenden Nährstoff- und Wasserflüsse eng miteinander verknüpft sind, sollten sie in einem konsistenten Modellansatz betrachtet werden. Dennoch haben Datenmangel und ungenügendes Prozessverständnis dies bis vor kurzem auf der globalen Skala verhindert. In dieser Arbeit wird die erste Version eines solchen konsistenten globalen Modellansatzes präsentiert, wobei der Schwerpunkt auf der Simulation landwirtschaftlicher Erträge und den resultierenden N2O-Emissionen liegt. Der Grund für diese Schwerpunktsetzung liegt darin, dass die korrekte Abbildung des Pflanzenwachstums eine essentielle Voraussetzung für die Simulation aller anderen Prozesse ist. Des weiteren sind aktuelle und potentielle landwirtschaftliche Erträge wichtige treibende Kräfte für Landnutzungsänderungen und werden stark vom Klimawandel betroffen sein. Den zweiten Schwerpunkt bildet die Abschätzung landwirtschaftlicher N2O-Emissionen, da bislang kein prozessbasiertes N2O-Modell auf der globalen Skala eingesetzt wurde. Als Grundlage für die globale Modellierung wurde das bestehende Agrarökosystemmodell Daycent gewählt. Neben der Schaffung der Simulationsumgebung wurden zunächst die benötigten globalen Datensätze für Bodenparameter, Klima und landwirtschaftliche Bewirtschaftung zusammengestellt. Da für Pflanzzeitpunkte bislang keine globale Datenbasis zur Verfügung steht, und diese sich mit dem Klimawandel ändern werden, wurde eine Routine zur Berechnung von Pflanzzeitpunkten entwickelt. Die Ergebnisse zeigen eine gute Übereinstimmung mit Anbaukalendern der FAO, die für einige Feldfrüchte und Länder verfügbar sind. Danach wurde das Daycent-Modell für die Ertragsberechnung von Weizen, Reis, Mais, Soja, Hirse, Hülsenfrüchten, Kartoffel, Cassava und Baumwolle parametrisiert und kalibriert. Die Simulationsergebnisse zeigen, dass Daycent die wichtigsten Klima-, Boden- und Bewirtschaftungseffekte auf die Ertragsbildung korrekt abbildet. Berechnete Länderdurchschnitte stimmen gut mit Daten der FAO überein (R2 = 0.66 für Weizen, Reis und Mais; R2 = 0.32 für Soja), und räumliche Ertragsmuster entsprechen weitgehend der beobachteten Verteilung von Feldfrüchten und subnationalen Statistiken. Vor der Modellierung landwirtschaftlicher N2O-Emissionen mit dem Daycent-Modell stand eine statistische Analyse von N2O-und NO-Emissionsmessungen aus natürlichen und landwirtschaftlichen Ökosystemen. Die als signifikant identifizierten Parameter für N2O (Düngemenge, Bodenkohlenstoffgehalt, Boden-pH, Textur, Feldfrucht, Düngersorte) und NO (Düngemenge, Bodenstickstoffgehalt, Klima) entsprechen weitgehend den Ergebnissen einer früheren Analyse. Für Emissionen aus Böden unter natürlicher Vegetation, für die es bislang keine solche statistische Untersuchung gab, haben Bodenkohlenstoffgehalt, Boden-pH, Lagerungsdichte, Drainierung und Vegetationstyp einen signifikanten Einfluss auf die N2O-Emissionen, während NO-Emissionen signifikant von Bodenkohlenstoffgehalt und Vegetationstyp abhängen. Basierend auf den daraus entwickelten statistischen Modellen betragen die globalen Emissionen aus Ackerböden 3.3 Tg N/y für N2O, und 1.4 Tg N/y für NO. Solche statistischen Modelle sind nützlich, um Abschätzungen und Unsicherheitsbereiche von N2O- und NO-Emissionen basierend auf einer Vielzahl von Messungen zu berechnen. Die Dynamik des Bodenstickstoffs, insbesondere beeinflusst durch Pflanzenwachstum, Klimawandel und Landnutzungsänderung, kann allerdings nur durch die Anwendung von prozessorientierten Modellen berücksichtigt werden. Zur Modellierung von N2O-Emissionen mit dem Daycent-Modell wurde zunächst dessen Spurengasmodul durch eine detailliertere Berechnung von Nitrifikation und Denitrifikation und die Berücksichtigung von Frost-Auftau-Emissionen weiterentwickelt. Diese überarbeitete Modellversion wurde dann an N2O-Emissionsmessungen unter verschiedenen Klimaten und Feldfrüchten getestet. Sowohl die Dynamik als auch die Gesamtsummen der N2O-Emissionen werden befriedigend abgebildet, wobei die Modelleffizienz für monatliche Mittelwerte zwischen 0.1 und 0.66 für die meisten Standorte liegt. Basierend auf der überarbeiteten Modellversion wurden die N2O-Emissionen für die zuvor parametrisierten Feldfrüchte berechnet. Emissionsraten und feldfruchtspezifische Unterschiede stimmen weitgehend mit Literaturangaben überein. Düngemittelinduzierte Emissionen, die momentan vom IPCC mit 1.25 +/- 1% der eingesetzten Düngemenge abgeschätzt werden, reichen von 0.77% (Reis) bis 2.76% (Mais). Die Summe der berechneten Emissionen aus landwirtschaftlichen Böden beträgt für die Mitte der 1990er Jahre 2.1 Tg N2O-N/y, was mit den Abschätzungen aus anderen Studien übereinstimmt.
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To unravel the settlement history of oases in northern Oman, data on topography, the agricultural setting, water and soil parameters and archaeological findings were collected in the Wadi Bani Awf with its head oasis Balad Seet. Data collection lasted from April 2000 to April 2003 and was based on the establishment of a 3D-georeferenced map of the oasis comprising all its major infrastructural and agronomic features. At today's Balad Seet, a total of 8.8 ha are planted to 2,800 date palms and 4.6 ha are divided into 385 small fields dedicated to wheat, barley, sorghum, oats, alfalfa, garlic, onion, lime and banana. Radiocarbon dating of charcoal in the lower part of the main terrace system determined its age to 911 ± 43 years. Monthly flow measurements of four major aflaj systems showed a total maximum flow of 32 m^3 h^-1 with the largest falaj contributing 78% of the total flow. During drought periods, average water flow decreased by 3% per month, however, with significant differences between the spring systems. The analysis of the tritium/^3helium ratio in the water led to an estimated water age of up to 10 years. In combination with the flow data, this provided insights into the elasticity of the spring flow over time. The use of the natural resources of the Wadi Bani Awf by a pastoral population started probably in the early 3rd millennium BC. The first permanent settlement might have been established at Balad Seet during the first part of the 1st millennium BC. Presumably it was initiated by settlers from al-Hamra, a village at the southern foot of the Hajar mountains. Given an abundant und stable flow of springs, even in periods of drought, the construction of Balad Seet's first irrigation systems may have occurred at this early time. The combination of topographic, agricultural, hydro-pedological and archaeological data allowed assessment of the carrying capacity of this oasis over the three millennia of its likely existence. The changing scarcity of land and water and the eventual optimisation of their use by different aflaj constructions have been major driving forces for the development and apparent relativeley stable existence of this oasis.
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Land use is a crucial link between human activities and the natural environment and one of the main driving forces of global environmental change. Large parts of the terrestrial land surface are used for agriculture, forestry, settlements and infrastructure. Given the importance of land use, it is essential to understand the multitude of influential factors and resulting land use patterns. An essential methodology to study and quantify such interactions is provided by the adoption of land-use models. By the application of land-use models, it is possible to analyze the complex structure of linkages and feedbacks and to also determine the relevance of driving forces. Modeling land use and land use changes has a long-term tradition. In particular on the regional scale, a variety of models for different regions and research questions has been created. Modeling capabilities grow with steady advances in computer technology, which on the one hand are driven by increasing computing power on the other hand by new methods in software development, e.g. object- and component-oriented architectures. In this thesis, SITE (Simulation of Terrestrial Environments), a novel framework for integrated regional sland-use modeling, will be introduced and discussed. Particular features of SITE are the notably extended capability to integrate models and the strict separation of application and implementation. These features enable efficient development, test and usage of integrated land-use models. On its system side, SITE provides generic data structures (grid, grid cells, attributes etc.) and takes over the responsibility for their administration. By means of a scripting language (Python) that has been extended by language features specific for land-use modeling, these data structures can be utilized and manipulated by modeling applications. The scripting language interpreter is embedded in SITE. The integration of sub models can be achieved via the scripting language or by usage of a generic interface provided by SITE. Furthermore, functionalities important for land-use modeling like model calibration, model tests and analysis support of simulation results have been integrated into the generic framework. During the implementation of SITE, specific emphasis was laid on expandability, maintainability and usability. Along with the modeling framework a land use model for the analysis of the stability of tropical rainforest margins was developed in the context of the collaborative research project STORMA (SFB 552). In a research area in Central Sulawesi, Indonesia, socio-environmental impacts of land-use changes were examined. SITE was used to simulate land-use dynamics in the historical period of 1981 to 2002. Analogous to that, a scenario that did not consider migration in the population dynamics, was analyzed. For the calculation of crop yields and trace gas emissions, the DAYCENT agro-ecosystem model was integrated. In this case study, it could be shown that land-use changes in the Indonesian research area could mainly be characterized by the expansion of agricultural areas at the expense of natural forest. For this reason, the situation had to be interpreted as unsustainable even though increased agricultural use implied economic improvements and higher farmers' incomes. Due to the importance of model calibration, it was explicitly addressed in the SITE architecture through the introduction of a specific component. The calibration functionality can be used by all SITE applications and enables largely automated model calibration. Calibration in SITE is understood as a process that finds an optimal or at least adequate solution for a set of arbitrarily selectable model parameters with respect to an objective function. In SITE, an objective function typically is a map comparison algorithm capable of comparing a simulation result to a reference map. Several map optimization and map comparison methodologies are available and can be combined. The STORMA land-use model was calibrated using a genetic algorithm for optimization and the figure of merit map comparison measure as objective function. The time period for the calibration ranged from 1981 to 2002. For this period, respective reference land-use maps were compiled. It could be shown, that an efficient automated model calibration with SITE is possible. Nevertheless, the selection of the calibration parameters required detailed knowledge about the underlying land-use model and cannot be automated. In another case study decreases in crop yields and resulting losses in income from coffee cultivation were analyzed and quantified under the assumption of four different deforestation scenarios. For this task, an empirical model, describing the dependence of bee pollination and resulting coffee fruit set from the distance to the closest natural forest, was integrated. Land-use simulations showed, that depending on the magnitude and location of ongoing forest conversion, pollination services are expected to decline continuously. This results in a reduction of coffee yields of up to 18% and a loss of net revenues per hectare of up to 14%. However, the study also showed that ecological and economic values can be preserved if patches of natural vegetation are conservated in the agricultural landscape. -----------------------------------------------------------------------
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Among organic materials, spirobifluorene derivatives represent a very attractive class of materials for electronic devices. These compounds have high melting points, glass transitions temperatures and morphological stability, which makes these materials suitable for organic electronic applications. In addition, some of spirobifluorenes can form porous supramolecular associations with significant volumes available for the inclusion of guests. These molecular associations based on the spirobifluorenes are noteworthy because they are purely molecular analogues of zeolites and other microporous solids, with potential applications in separation, catalysis, sensing and other areas.
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The objective of this study was to develop an internet-based seminar framework applicable for landscape architecture education. This process was accompanied by various aims. The basic expectation was to keep the main characteristics of landscape architecture education also in the online format. On top of that, four further objectives were anticipated: (1) training of competences for virtual team work, (2) fostering intercultural competence, (3) creation of equal opportunities for education through internet-based open access and (4) synergy effects and learning processes across institutional boundaries. This work started with the hypothesis that these four expected advantages would compensate for additional organisational efforts caused by the online delivery of the seminars and thus lead to a sustainable integration of this new learning mode into landscape architecture curricula. This rationale was followed by a presentation of four areas of knowledge to which the seminar development was directly related (1) landscape architecture as a subject and its pedagogy, (2) general learning theories, (3) developments in the ICT sector and (4) wider societal driving forces such as global citizenship and the increase of open educational resources. The research design took the shape of a pedagogical action research cycle. This approach was constructive: The author herself is teaching international landscape architecture students so that the model could directly be applied in practice. Seven online seminars were implemented in the period from 2008 to 2013 and this experience represents the core of this study. The seminars were conducted with varying themes while its pedagogy, organisation and the technological tools remained widely identical. The research design is further based on three levels of observation: (1) the seminar design on the basis of theory and methods from the learning sciences, in particular educational constructivism, (2) the seminar evaluation and (3) the evaluation of the seminars’ long term impact. The seminar model itself basically consists of four elements: (1) the taxonomy of learning objectives, (2) ICT tools and their application and pedagogy, (3) process models and (4) the case study framework. The seminar framework was followed by the presentation of the evaluation findings. The major findings of this study can be summed up as follows: Implementing online seminars across educational and national boundaries was possible both in term of organisation and technology. In particular, a high level of cultural diversity among the seminar participants has definitively been achieved. However, there were also obvious obstacles. These were primarily competing study commitments and incompatible schedules among the students attending from different academic programmes, partly even in different time zones. Both factors had negative impact on the individual and working group performances. With respect to the technical framework it can be concluded that the majority of the participants were able to use the tools either directly without any problem or after overcoming some smaller problems. Also the seminar wiki was intensively used for completing the seminar assignments. However, too less truly collaborative text production was observed which could be improved by changing the requirements for the collaborative task. Two different process models have been applied for guiding the collaboration of the small groups and both were in general successful. However, it needs to be said that even if the students were able to follow the collaborative task and to co-construct and compare case studies, most of them were not able to synthesize the knowledge they had compiled. This means that the area of consideration often remained on the level of the case and further reflections, generalisations and critique were largely missing. This shows that the seminar model needs to find better ways for triggering knowledge building and critical reflection. It was also suggested to have a more differentiated group building strategy in future seminars. A comparison of pre- and post seminar concept maps showed that an increase of factual and conceptual knowledge on the individual level was widely recognizable. Also the evaluation of the case studies (the major seminar output) revealed that the students have undergone developments of both the factual and the conceptual knowledge domain. Also their self-assessment with respect to individual learning development showed that the highest consensus was achieved in the field of subject-specific knowledge. The participants were much more doubtful with regard to the progress of generic competences such as analysis, communication and organisation. However, 50% of the participants confirmed that they perceived individual development on all competence areas the survey had asked for. Have the additional four targets been met? Concerning the competences for working in a virtual team it can be concluded that the vast majority was able to use the internet-based tools and to work with them in a target-oriented way. However, there were obvious differences regarding the intensity and activity of participation, both because of external and personal factors. A very positive aspect is the achievement of a high cultural diversity supporting the participants’ intercultural competence. Learning from group members was obviously a success factor for the working groups. Regarding the possibilities for better accessibility of educational opportunities it became clear that a significant number of participants were not able to go abroad during their studies because of financial or personal reasons. They confirmed that the online seminar was to some extent a compensation for not having been abroad for studying. Inter-institutional learning and synergy was achieved in so far that many teachers from different countries contributed with individual lectures. However, those teachers hardly ever followed more than one session. Therefore, the learning effect remained largely within the seminar learning group. Looking back at the research design it can be said that the pedagogical action research cycle was an appropriate and valuable approach allowing for strong interaction between theory and practice. However, some more external evaluation from peers in particular regarding the participants’ products would have been valuable.
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The traditional task of a central bank is to preserve price stability and, in doing so, not to impair the real economy more than necessary. To meet this challenge, it is of great relevance whether inflation is only driven by inflation expectations and the current output gap or whether it is, in addition, influenced by past inflation. In the former case, as described by the New Keynesian Phillips curve, the central bank can immediately and simultaneously achieve price stability and equilibrium output, the so-called ‘divine coincidence’ (Blanchard and Galí 2007). In the latter case, the achievement of price stability is costly in terms of output and will be pursued over several periods. Similarly, it is important to distinguish this latter case, which describes ‘intrinsic’ inflation persistence, from that of ‘extrinsic’ inflation persistence, where the sluggishness of inflation is not a ‘structural’ feature of the economy but merely ‘inherited’ from the sluggishness of the other driving forces, inflation expectations and output. ‘Extrinsic’ inflation persistence is usually considered to be the less challenging case, as policy-makers are supposed to fight against the persistence in the driving forces, especially to reduce the stickiness of inflation expectations by a credible monetary policy, in order to reestablish the ‘divine coincidence’. The scope of this dissertation is to contribute to the vast literature and ongoing discussion on inflation persistence: Chapter 1 describes the policy consequences of inflation persistence and summarizes the empirical and theoretical literature. Chapter 2 compares two models of staggered price setting, one with a fixed two-period duration and the other with a stochastic duration of prices. I show that in an economy with a timeless optimizing central bank the model with the two-period alternating price-setting (for most parameter values) leads to more persistent inflation than the model with stochastic price duration. This result amends earlier work by Kiley (2002) who found that the model with stochastic price duration generates more persistent inflation in response to an exogenous monetary shock. Chapter 3 extends the two-period alternating price-setting model to the case of 3- and 4-period price durations. This results in a more complex Phillips curve with a negative impact of past inflation on current inflation. As simulations show, this multi-period Phillips curve generates a too low degree of autocorrelation and too early turnings points of inflation and is outperformed by a simple Hybrid Phillips curve. Chapter 4 starts from the critique of Driscoll and Holden (2003) on the relative real-wage model of Fuhrer and Moore (1995). While taking the critique seriously that Fuhrer and Moore’s model will collapse to a much simpler one without intrinsic inflation persistence if one takes their arguments literally, I extend the model by a term for inequality aversion. This model extension is not only in line with experimental evidence but results in a Hybrid Phillips curve with inflation persistence that is observably equivalent to that presented by Fuhrer and Moore (1995). In chapter 5, I present a model that especially allows to study the relationship between fairness attitudes and time preference (impatience). In the model, two individuals take decisions in two subsequent periods. In period 1, both individuals are endowed with resources and are able to donate a share of their resources to the other individual. In period 2, the two individuals might join in a common production after having bargained on the split of its output. The size of the production output depends on the relative share of resources at the end of period 1 as the human capital of the individuals, which is built by means of their resources, cannot fully be substituted one against each other. Therefore, it might be rational for a well-endowed individual in period 1 to act in a seemingly ‘fair’ manner and to donate own resources to its poorer counterpart. This decision also depends on the individuals’ impatience which is induced by the small but positive probability that production is not possible in period 2. As a general result, the individuals in the model economy are more likely to behave in a ‘fair’ manner, i.e., to donate resources to the other individual, the lower their own impatience and the higher the productivity of the other individual. As the (seemingly) ‘fair’ behavior is modelled as an endogenous outcome and as it is related to the aspect of time preference, the presented framework might help to further integrate behavioral economics and macroeconomics.
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At many locations in Myanmar, ongoing changes in land use have negative environmental impacts and threaten natural ecosystems at local, regional and national scales. In particular, the watershed area of Inle Lake in eastern Myanmar is strongly affected by the environmental effects of deforestation and soil erosion caused by agricultural intensification and expansion of agricultural land, which are exacerbated by the increasing population pressure and the growing number of tourists. This thesis, therefore, focuses on land use changes in traditional farming systems and their effects on socio-economic and biophysical factors to improve our understanding of sustainable natural resource management of this wetland ecosystem. The main objectives of this research were to: (1) assess the noticeable land transformations in space and time, (2) identify the typical farming systems as well as the divergent livelihood strategies, and finally, (3) estimate soil erosion risk in the different agro-ecological zones surrounding the Inle Lake watershed area. GIS and remote sensing techniques allowed to identify the dynamic land use and land cover changes (LUCC) during the past 40 years based on historical Corona images (1968) and Landsat images (1989, 2000 and 2009). In this study, 12 land cover classes were identified and a supervised classification was used for the Landsat datasets, whereas a visual interpretation approach was conducted for the Corona images. Within the past 40 years, the main landscape transformation processes were deforestation (- 49%), urbanization (+ 203%), agricultural expansion (+ 34%) with a notably increase of floating gardens (+ 390%), land abandonment (+ 167%), and marshlands losses in wetland area (- 83%) and water bodies (- 16%). The main driving forces of LUCC appeared to be high population growth, urbanization and settlements, a lack of sustainable land use and environmental management policies, wide-spread rural poverty, an open market economy and changes in market prices and access. To identify the diverse livelihood strategies in the Inle Lake watershed area and the diversity of income generating activities, household surveys were conducted (total: 301 households) using a stratified random sampling design in three different agro-ecological zones: floating gardens (FG), lowland cultivation (LL) and upland cultivation (UP). A cluster and discriminant analysis revealed that livelihood strategies and socio-economic situations of local communities differed significantly in the different zones. For all three zones, different livelihood strategies were identified which differed mainly in the amount of on-farm and off-farm income, and the level of income diversification. The gross margin for each household from agricultural production in the floating garden, lowland and upland cultivation was US$ 2108, 892 and 619 ha-1 respectively. Among the typical farming systems in these zones, tomato (Lycopersicon esculentum L.) plantation in the floating gardens yielded the highest net benefits, but caused negative environmental impacts given the overuse of inorganic fertilizers and pesticides. The Revised Universal Soil Loss Equation (RUSLE) and spatial analysis within GIS were applied to estimate soil erosion risk in the different agricultural zones and for the main cropping systems of the study region. The results revealed that the average soil losses in year 1989, 2000 and 2009 amounted to 20, 10 and 26 t ha-1, respectively and barren land along the steep slopes had the highest soil erosion risk with 85% of the total soil losses in the study area. Yearly fluctuations were mainly caused by changes in the amount of annual precipitation and the dynamics of LUCC such as deforestation and agriculture extension with inappropriate land use and unsustainable cropping systems. Among the typical cropping systems, upland rainfed rice (Oryza sativa L.) cultivation had the highest rate of soil erosion (20 t ha-1yr-1) followed by sebesten (Cordia dichotoma) and turmeric (Curcuma longa) plantation in the UP zone. This study indicated that the hotspot region of soil erosion risk were upland mountain areas, especially in the western part of the Inle lake. Soil conservation practices are thus urgently needed to control soil erosion and lake sedimentation and to conserve the wetland ecosystem. Most farmers have not yet implemented soil conservation measures to reduce soil erosion impacts such as land degradation, sedimentation and water pollution in Inle Lake, which is partly due to the low economic development and poverty in the region. Key challenges of agriculture in the hilly landscapes can be summarized as follows: fostering the sustainable land use of farming systems for the maintenance of ecosystem services and functions while improving the social and economic well-being of the population, integrated natural resources management policies and increasing the diversification of income opportunities to reduce pressure on forest and natural resources.