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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
301

Effondrement et reconstruction de l'Etat : les continuités de la formation de l'Etat sierra léonais

Jalloh, Mohamed 08 April 2011 (has links) (PDF)
Cette thèse avance que le cas de la Sierra Leone est édifiant pour comprendre le paradoxe de l'effondrement et de la reconstruction des Etats africains néo-patrimoniaux dans l'ère post-Guerre Froide. Il vise à identifier les processus historiques, politiques et sociaux spécifiques qui ont mené à l'effondrement de l'Etat en Sierra Leone, mais aussi les dynamiques à l'oeuvre dans sa reconstruction. Elle s'appuie sur l"hypothèse selon laquelle l'effondrement et la reconstruction de l'Etat révèlent des continuités de la formation de l'Etat en Sierra Leone.
302

A Geochemical Exploration of the Sagehen Volcanic Centre, Truckee-Tahoe Region, California, U.S.A.

Clarke, Christopher Angus Leo 13 June 2012 (has links)
The assemblage of ca. 6–4 Ma volcanic rocks exposed at the Sagehen Research station in the Truckee-Tahoe region of the northern Sierra Nevada, United States, is interpreted to be, within the Ancestral Cascades volcanic arc, a Lassen-type stratovolcano complex. Sagehen is of particular importance because it is one of the few Tertiary arc volcanic centres in California which has not been heavily glaciated during the Pleistocene. The volcanic rocks are variably porphyritic or aphanitic, including abundant plagioclase with clinopyroxene and amphibole. The rocks range from basalt to basaltic-andesite to andesite in composition. Basalts are olivineand clinopyroxene-bearing with minor phenocrysts of plagioclase. The basaltic-andesites are primarily pyroxene bearing while the andesites contain pyroxene-, plagioclase- and hornblende porphyritic phases. Sagehen arc lavas are calc-alkaline and enriched in the large ion lithophile elements and depleted in High Field Strength Elements. The basalts are depleted in Zr and Hf while the andesites are enriched with Zr and Hf relative to the middle rare earth elements. Compared to previously studied Ancestral Cascade arc samples, Sagehen region basalts have lower 143Nd/144Nd isotopic values that do not correspond to proposed mantle-lithosphere mixing lines, while the andesite samples appear to represent the interplay of these two components on a 87Sr/86Sr vs. 143Nd/144Nd. The trace element data and isotopic plots suggest that the melts that produced the basalts are from subduction modified mantle wedge peridotites that ponded near the base of the lithosphere similar to the generation of other subduction related calc-alkaline lavas along convergent continental margins. The andesitic samples appear to be the result of further modification through crustal assimilation as seen in the higher isotopic Sr contents in the andesites and Ce/Smpmn vs. Tb/Ybpmn plots. Finally, the proposed map units from Sylvester & Raines (2007) were found to contain various geochemical facies based on the samples collected indicating that some map units may have to be redefined or sub-divided.
303

Abundance and habitat relationships of breeding birds in the Sky Islands and adjacent Sierra Madre Occidental of northwest Mexico

Flesch, Aaron D., Gonzalez Sanchez, Carlos, Valenzuela Amarillas, Javier 06 1900 (has links)
The Sierra Madre Occidental and neighboring Madrean Sky Islands span a large and biologically diverse region of northwest Mexico and portions of the southwestern United States. Little is known about the abundance and habitat use of breeding birds in this region of Mexico, but such information is important for guiding conservation and management. We assessed densities and habitat relationships of breeding birds across Sky Island mountain ranges in Mexico and adjacent portions of the Sierra Madre from 2009 to 2012. We estimated densities at multiple spatial scales, assessed variation in densities among all major montane vegetation communities, and identified and estimated the effects of important habitat attributes on local densities. Regional density estimates of 65% of 72 focal species varied significantly among eight montane vegetation communities that ranged from oak savannah and woodland at low elevations to pine and mixed-conifer forest at high elevations. Greater proportions of species occurred at peak densities or were relatively restricted to mixed-conifer forest and montane riparian vegetation likely because of higher levels of structural or floristic diversity in those communities, but those species were typically rare or uncommon in the Sky Islands. Fewer species had peak densities in oak and pine-oak woodland, and species associated with those communities were often more abundant across the region. Habitat models often included the effects of broadleaf deciduous vegetation cover (30% of species), which, together with tree density and fire severity, had positive effects on densities and suggest ways for managers to augment and conserve populations. Such patterns combined with greater threats to high-elevation conifer forest and riparian areas underscore their value for conservation. Significant populations of many breeding bird species, including some that are of concern or were not known to occur regionally or in mountain ranges we surveyed, highlight the importance of conservation efforts in this area of Mexico.
304

The financial costs of delivering rural water and sanitation services in lower-income countries

Burr, Peter William January 2014 (has links)
Despite the impressive progress over the last two decades in which millions of people worldwide have gained first time access to improved water and sanitation infrastructure, the reality for many is that shortly after infrastructure construction the actual service received by users slips back to unacceptably low levels. However, due to inadequate research and inconsistencies with how data and cost data has been collected and reported, very little is known of the necessary levels of expenditure required to sustain an acceptable (so called “basic”) water and sanitation service and this inhibits effective financial planning for households, communities, governments and donors alike. This thesis sought to provide a better understanding of what has historically been spent to provide different levels of water and sanitation services as a means to better understand the necessary expenditure required. Empirical findings are based on a large data sample of nearly 2,000 water points, over 4,000 latrines, and over 12,000 household surveys, which have been collected as part of three research projects (WASHCost, Triple-S, and WASHCost Sierra Leone), across five country research areas (Andhra Pradesh (India), Burkina Faso, Ghana, Mozambique, and Sierra Leone). Findings for water supply systems show that the combination of high capital investments of: $19 and $69 per person for community point sources and $33 – $216 per person for piped systems; and low recurrent expenditures of: $0.06 - $0.37 per person per year for point sources and $0.58 - $7.87 per person per year for piped systems; results in less than half of users receiving a “basic” level of service. Evidence based estimates of the required expenditure for acceptable services are found to be far greater than the “effective demand” expressed in terms of the willingness to pay of service users and national government for these services. Findings for sanitation show that constructing a household latrine that achieves “basic” service standards requires a financial investment of at least $40 that is likely to be an unaffordable barrier for many households in lower income countries. In addition the costs and affordability of periodic pit emptying remains a concern. Ultimately this research suggests that if international standard of improved water and sanitation services are to be sustained in rural areas, the international sector will likely have to provide additional investments to meet a significant proportion of the recurrent costs of delivering these services.
305

Civil War resolution : the private military industry, asymmetric warfare, and ripeness

Bode, Daisy-Ivy January 2007 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
306

Opening Pandora's Box? : theorising the commercialisation of military force in the post-Cold War world

Street, Daniel January 2016 (has links)
The commercialisation of military services has increased in importance since the end of the Cold War. Commercial Military Service Providers (CMSPs) have found increased respectability and worked in states on every continent. Writing on CMSPs has similarly increased. Several high profile incidents have come under intense scrutiny, and has led to some portions of the literature demonising their use. However, there are still conceptual and theoretical issues which have been under explored. This thesis contributes to the literature which has sought to address this theoretical lacuna. Historical Sociology and comparative analysis are employed to analyse the implications of CMSP use on the state. A modified version of the Ideological, Economic, Military and Political (IEMP) model developed by Michael Mann, is used to theorise the impact of commercial security providers on existing sources of power within the state, and the relationship between them. The thesis uses two case studies which are representative of the use of CMSPs during this time period. The Sierra Leone Civil War and the invasion and reconstruction of Iraq since 2003. It will be argued that CMSPs alter the balance between power structures within the state, positively and negatively affecting the power of the state. The short term use of CMSPs has proven to be useful and of increasing importance; especially when military weakness is an urgent problem. However, although there has been no example of CMSPs intentionally threatening state stability, they can also subvert the power of the state. CMSPs, particularly when used for an extended period, have undermined the relationship between the sources of power, undermining political stability. Most significantly they weakened the state by undermining the strength it gains from its embeddedness in society.
307

Structural Analysis and a Kink Band Model for the Formation of the Gemini Fault Zone, an Exhumed Left-Lateral Strike Slip Fault Zone in the Central Sierra Nevada, California

Pachell, Matthew A. 01 May 2001 (has links)
The structure and regional tectonic setting of an exhumed, 9.3-km long, left-lateral strike-slip fault zone eludicates processes of growth, linkage, and termination for strike-slip fault zones in granitic rocks. The Gemini fault zone is composed of three steeply dipping, southwest-striking, noncoplanar segments that nucleated and grew along preexisting joints. The fault zone has a maximum slip of 131 m and is an example of a segmented, hard-linked fault zone in which geometrical complexities of the faults and compositional variations of protolith and host rock resulted in nonuniform slip orientations, complex interactions at fault segments, and an asymmetric slip-distance profile. Regional structural analysis shows that joints and left-lateral fault zones have accommodated slip within a 4.8-km wide, right-lateral monoclinical kink band with vertical fold axes and northwest-striking axial surfaces. Geometric modeling of the kink band indicates that as little as 1.1 km of right-lateral displacement across the kink band may have produced the observed slip on kilometer-scale faults within the kink band.
308

ETUDE GEOLOGIQUE DE LA SIERRA MADRE DEL SUR AUX ENVIRONS DE CHILPANCINGO ET D'OLINALA, GRO.: Une contribution à la connaissance de l'évolution géodynamique de la marge pacifique du Mexique depuis le Jurassique

GARCIA-DIAZ, José Luis 25 June 2004 (has links) (PDF)
L'étude concerne la Sierra Madre del Sur, chaîne montagneuse qui borde la côte pacifique parallèlement à la fosse de subduction d'Acapulco. Elle est fondée sur la cartographie géologique de deux secteurs représentatifs situés dans l'Etat de Guerrero (l'un autour d'Olinalá, l'autre aux environs de la capitale Chilpancingo) et sur la réalisation de coupes à l'échelle 1/1. Son but est d'individualiser les ensembles géologiques significatifs et de caractériser les structures liées aux diverses étapes de déformation ; ceci afin de reconstituer l'évolution de la sierra depuis le Jurassique inférieur, en la replaçant dans le cadre géodynamique de la partie sud du Mexique située actuellement au carrefour des plaques Amérique du Nord, Caraïbe et Cocos.<br /><br />La première partie concerne l'architecture et l'histoire de la sierra, abordées par les approches stratigraphiques et pétrographiques et par l'analyse structurale rétrotectonique. Le soubassement continental pré – jurassique (partie du bloc d'Oaxaca) comprend un socle – né de l'assemblage des « terranes » Oaxaca et Mixtèque au Paléozoïque inférieur – pourvu localement de sa couverture sédimentaire du Paléozoïque supérieur peu déformée; le Complexe Xolapa qui affleure le long de la côte, est une partie inférieure de cette croûte, migmatisée et granitisée en tant que racine des arcs jurassique et paléogène, et exhumée récemment. Dans l'ensemble du Jurassique moyen, sont reconnues les roches volcaniques et volcanoclastiques à dominante acide (Formation Chapolapa) d'un arc auquel est associé le bassin arrière-arc de Tecocoyunca. Les deux sont tectonisés et métamorphisés (schiste vert) par la phase compressive névadienne du Jurassique supérieur. En liaison avec la montée eustatique, le Crétacé inférieur est marqué par la transgression marine et le dépôt en discordance des formations néritiques à récifales de l'épaisse plate-forme carbonatée de Guerrero – Morelos. C'est sur le bord « pacifique » de celle-ci que s'effectue, à la base du Crétacé supérieur, le charriage du « terrane » Guerrero (arc intra-océanique engendré durant le Jurassique supérieur et le Crétacé inférieur) par collision arc – continent. Une conséquence majeure de cet événement est la formation, à l'avant du front de charriage, d'un bassin flexural dans lequel une puissante série terrigène (flysch Mexcala) s'accumule, durant le Crétacé supérieur et le Paléocène. Ce bassin, affecté par la phase laramienne, subit, au Paléocène supérieur – Eocène inférieur, un fort raccourcissement est-ouest, accomodé par le plissement de la couverture décollée et par l'écaillage du socle. L'ensemble discordant, paléogène et miocène inférieur, comprend des molasses continentales post-laramiennes (Formation Balsas) passant latéralement et verticalement au plastron volcanique à dominante ignimbritique engendré par la subduction de l'ancienne plaque Farallon ; il est déformé par des plis de fond nord – nord-ouest – sud – sud-est du Miocène inférieur. Depuis le Miocène et suite au départ du bloc Chortis l'évolution, encore en cours, de la Sierra Madre del Sur est sous la dépendance de la subduction de la plaque Cocos : c'est elle qui induit et entretient l'exhumation de la croûte continentale inférieure du bloc d'Oaxaca (entre la surface de subduction et une surface majeure de détachement crustale en faille normale) avec mise à jour du Complexe de Xolapa et déformation en antiforme de la Sierra Madre del Sur, parallèlement à la fosse de subduction d'Acapulco et donc très obliquement par rapport aux structures antérieures mésozoïques et tertiaires recoupées.<br /><br />La deuxième partie est d'abord l'occasion de préciser, par la mise en œuvre de l'outil pétro-géochimique, les environnements géodynamiques de la genèse de deux ensembles géologiques présents dans la Sierra Madre del Sur et qui sont des marqueurs essentiels de l'évolution de la marge mexicaine: l'arc volcanique Chapolapa du Jurassique moyen dont l'importance a, jusqu'à présent, été mésestimée et l'arc volcanique jurassique supérieur – crétacé inférieur du « terrane » Guerrero.<br />Les caractéristiques pétrographiques, la géochimie des éléments majeurs, la géochimie des éléments traces et la géochimie isotopique des roches volcaniques généralement acides de l'arc Chapolapa, indiquent qu'elles s'apparentent aux séries calco-alcalines d'un ancien arc de type andin. Elles dérivent de la fusion d'un manteau asthénosphérique contaminé par les fluides de la croûte océanique paléo-pacifique hydrothermalisée, par des sédiments entraînés dans la subduction et, vraisemblablement, par la croûte continentale nord-américaine (bloc d'Oaxaca) sur laquelle elles reposent<br />Les roches volcaniques (laves acides et andésites du Crétacé inférieur) du « terrane » Guerrero présent dans cette partie de la Sierra Madre del Sur sont également calco-alcalines. Mais les indicateurs géochimiques confirment que leur contexte de mise en place était celui d'un arc insulaire intra-Pacifique<br />Ces résultats sont, par la suite, intégrés dans la présentation, en 2D, d'un modèle évolutif de la Sierra Madre del Sur. Celui-ci, construit, en six étapes selon le calendrier établi dans la première partie, schématise l'évolution de cet édifice, depuis le Jurassique jusqu'à l'actuel.<br /><br /> Dans la troisième partie et sur la base d'une recherche bibliographique, une synthèse est réalisée sur les constituants jurassiques présents, comme dans la Sierra Madre del Sur, à l'avant du « terrane » Guerrero sur l'ancien bord du continent nord-américain. En retrouvant des caractéristiques pétrologiques, géochimiques, stratigraphiques et structurales comparables, la présence d'une ancienne chaîne liminaire névadienne est mise en évidence, depuis la Californie jusqu'au Honduras, même si sa continuité initiale à été décalée de façon sénestre et sur plusieurs centaines de kilomètres par des failles transformantes, d'une part dans le nord du Mexique au Jurassique supérieur – Crétacé inférieur, d'autre part au sud du Mexique et au Guatemala depuis le Paléogène. Cette donnée essentielle est intégrée dans un modèle d'évolution palinspathique du Mexique, présenté depuis le Jurassique en six cartes.
309

Conflict Resolution in West Africa: A Comparative Analysis of Sierra Leone and Liberia

Abdul-Mumuni, Abdallah January 2005 (has links)
<p>This paper is a Master thesis for the Master’s program in International and European Relations in the Department of Management and Economics at Linköping University. As the title indicates, the aim of this thesis is to make a comparative analysis of the conflict resolution initiatives that were employed in the Sierra Leonean and Liberian conflicts. The research questions are:</p><p> • What were the root causes and trajectories of the Sierra Leonean and Liberian conflicts? </p><p>• What were the conflict resolution initiatives employed in resolving both conflicts? </p><p>• Why did the Lome Peace Accord succeed in the case of Sierra Leone whilst the Abuja Peace Accord failed in bringing peace to Liberia? </p><p>In order to answer the afore-mentioned questions and fulfil the aim of this paper, a qualitative research method has been chosen. The study is mainly based on secondary sources such as textbooks, official documents from ECOWAS and the UN, articles, magazines and newspapers as well as internet resources. In making the comparative analysis the Conflict Transformation Model as espoused by Kumar Rupesinghe has been utilized. This model has specifically helped in explaining the reasons why peace returned to Sierra Leone but eluded the people of Liberia for a long time. The conclusion drawn from the study is that a multi-track approach is required in dealing with conflicts in West Africa so that it would touch on the context of the conflict, the conflict structure, the intra-party as well as the inter- party divisions and the broader system of society and governance within the conflict area.</p>
310

Conflict Resolution in West Africa: A Comparative Analysis of Sierra Leone and Liberia

Abdul-Mumuni, Abdallah January 2005 (has links)
This paper is a Master thesis for the Master’s program in International and European Relations in the Department of Management and Economics at Linköping University. As the title indicates, the aim of this thesis is to make a comparative analysis of the conflict resolution initiatives that were employed in the Sierra Leonean and Liberian conflicts. The research questions are: • What were the root causes and trajectories of the Sierra Leonean and Liberian conflicts? • What were the conflict resolution initiatives employed in resolving both conflicts? • Why did the Lome Peace Accord succeed in the case of Sierra Leone whilst the Abuja Peace Accord failed in bringing peace to Liberia? In order to answer the afore-mentioned questions and fulfil the aim of this paper, a qualitative research method has been chosen. The study is mainly based on secondary sources such as textbooks, official documents from ECOWAS and the UN, articles, magazines and newspapers as well as internet resources. In making the comparative analysis the Conflict Transformation Model as espoused by Kumar Rupesinghe has been utilized. This model has specifically helped in explaining the reasons why peace returned to Sierra Leone but eluded the people of Liberia for a long time. The conclusion drawn from the study is that a multi-track approach is required in dealing with conflicts in West Africa so that it would touch on the context of the conflict, the conflict structure, the intra-party as well as the inter- party divisions and the broader system of society and governance within the conflict area.

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