• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1105
  • 632
  • 592
  • 358
  • 126
  • 75
  • 52
  • 42
  • 40
  • 26
  • 19
  • 19
  • 19
  • 19
  • 19
  • Tagged with
  • 3686
  • 966
  • 823
  • 489
  • 342
  • 303
  • 278
  • 271
  • 224
  • 220
  • 219
  • 208
  • 181
  • 177
  • 174
  • 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.
311

The archaeological record of the Galatians in Anatolia, 278-63 B.C.

Nixon, Lucia Frances January 1977 (has links)
The Galatians were a group of Celts who arrived in Anatolia from the west in 278 B.C. According to the historical sources, they earned their livelihood by plundering and by serving as mercenaries in the eastern Mediterranean. Ancient authors state that the Galatians constituted a definite threat to the cities of western Asia Minor before they were settled in central Anatolia. Galatia became a Roman province in 25 B.C.; by that time, the Galatians had been thoroughly absorbed by the local population. The purpose of this paper is to see what archaeological evidence exists for the presence of the Galatians in Anatolia during the pre-provincial period, and how that evidence can be obtained. Three types of evidence are examined: pottery, burials and grave goods, and forts and settlements. Galatian pottery is still a controversial subject requiring more study and excavation. Only one burial site, Karalar, can definitely be identified by an inscription in Greek. The evidence from this site suggests that the Galatians adopted various types of Hellenistic tomb architecture and that they placed a fundamentally Hellenistic selection of grave goods within their tombs and graves. Galatian burials are therefore hard to distinguish from ordinary Hellenistic burials in Anatolia. Three tores and three fibulae from burials at Karalar, Bolu, and Bogazk5y are probably Celtic; that there are so few of them suggests that they had been imported from Europe, and that the Galatians were not themselves metalworkers in the Celtic tradition. Such objects cannot be used as the sole means of identifying Galatian burials. The situation is little better for forts and settlements. Some have been identified because they were inhabited by literate people before or after the arrival of the Galatians; others have been suggested because of the likelihood of their location. Settlement seems to be more dense west of the Halys but more surveys and excavation are necessary to test this emerging pattern. So far, the pre-provincial period has yielded little in the way of archaeological evidence for the presence of the Galatians in Anatolia, despite the solid background provided by the historical sources. The Galatians had little connection with the European Celts and adapted easily to local customs. This capacity for adaptation makes it difficult to say what is Galatian and what is Anatolian Hellenistic. Only further work in the field can remedy this state of affairs. / Arts, Faculty of / Classical, Near Eastern and Religious Studies, Department of / Graduate
312

The analysis of the factors affecting household water demand in Mpumalanga, South Africa

van Huyssteen, Thomas 16 September 2021 (has links)
Understanding the evolution of water demand is of paramount importance for countries that want to implement the correct water demand management strategies that aim at increasing water use efficiency. This paper analyses household water demand in the capital city of the Mpumalanga Province of South Africa, in order to develop a better understanding of residential water demand in developing country contexts. Using survey data from 526 households in the Mbombela Municipality of Mpumalanga, South Africa, we estimate the price and income elasticities of household water demand, and investigate the factors that drive water demand of households that are located in heterogenous income groups. Households in the study areas have the unique characteristic seen in developing countries of having access to several sources of water, such as tap, ground and rainwater, implying the possibility of substitution. We run different estimation strategies that range from OLS, 2SLS and instrumental variable approaches to identify the factors that influence urban water demand. The findings reflect that price and income elasticities vary across different household groups, with price elasticities ranging from -0.140 to -0.879 and income elasticities ranging from 0.172 to 0.628. Other statistically significant variables which drive household water consumption are household size, education level, use of water saving technologies, and the use of rainwater tanks and systems. A crucial finding in this study was that water saving technologies were revealed to reduce water consumption levels by between 28.3% to 43.4%, and we hence provide specific policy recommendations based upon this finding. Overall, the results from this study can contribute substantially towards the development of appropriate and sustainable water policy making in South Africa.
313

Fairness Within: Sources and Consequences of Procedural Fairness in Police Agencies

January 2020 (has links)
abstract: Over the last decade, scholars have become increasingly attentive to the role of procedural fairness in shaping police officer attitudes and behaviors. In Chapter 1, I review key developments within this research, and identify several theoretical and methodological issues present in the current literature. I then outline the issues I seek to address through the three studies presented in this dissertation. In Chapter 2, I explore a divergence in how scholars conceptualize and measure sources of internal procedural fairness (IPF) within police departments. I discuss the implications of these divergences, and then compare three conceptualizations of IPF sources. I find that officers appear to form separate IPF judgement for each source, and that each procedural fairness judgment has unique associations with several outcomes. In Chapter 3, I examine the relationship between internal procedural fairness and officer engagement in external procedural fairness (EPF). Drawing upon the group engagement model (GEM), I argue that the relationship between IPF and EPF is mediated by organizational identification. Comparing the GEM against the prevailing explanation for this relationship, I find that the GEM better accounts for the relationship between IPF and EPF. In Chapter 4, I explore the role of organizational emphasis in shaping police officer support for several different policing strategies. The GEM suggests that IPF will simply bond officers to organizational goals and norms; it is this bond that motivates officers to adopt the strategies emphasized by their department. Examining support for several policing strategies, I find that officers who are more committed to their agency are more sensitive to changes in the emphasis placed on specific strategies. In Chapter 5, I review the findings of the various studies presented in this dissertation and discuss the implications of this research. Collectively, these three studies offer several insights into how IPF shapes police officer attitudes and behaviors. They highlight the importance of officer identification with organizational norms and value in shaping police officer attitudes and behaviors and establish new avenues for IPF research within police organizations. / Dissertation/Thesis / Doctoral Dissertation Criminology and Criminal Justice 2020
314

An investigation into the morphology of radio sources

Ella, Moloko Malebo January 2021 (has links)
>Magister Scientiae - MSc / Radio galaxies are some of the most unusual and powerful objects in the Universe and are therefore vital for so many reasons. Studies of Radio-Loud Active Galactic Nuclei (AGN) gives us the potential to enhance our understanding of the key processes leading to the ejection of material, connection to the central engine and how the jets are launched. Besides, the energetic input of these sources is thought to have an impact in the star formation history and properties of the ISM and ICM; thus by studying them, we can improve our understanding of their formation, evolution and their environment.
315

Water governance & international cooperation over trans-boundary water courses in Southern Africa: the case of the Okavango River Basin

Bybee, Megan Claire January 2015 (has links)
Includes bibliographical references / This dissertation seeks to explore the core drivers of international cooperation over shared water courses particularly in Southern African, using the example of the Okavango River Basin as a case study. As a starting point it highlights the hydro-political context of Southern African, which is dominated by more than 21 shared water courses and faces significant challenges to its water sector namely through climate variability and population growth. In light of these pressing issues which could create a security complex for sovereign riparian states, international cooperation over trans-boundary water sources is imperative. Drawing on core theories of international relations, this dissertation suggests that cooperation between riparian states is a result of strong institutional frameworks, at a river-basin, regional and international level. Cooperation is further reinforced through development functionalism which plays an important role in facilitating cooperation through the advancement of regional development goals and initiatives. Finally, the dissertation explores the role of international norms of cooperation over trans-boundary water courses and the important role they play in fostering cooperation. Using the case of the Okavango River Basin, the dissertation suggests that in Southern Africa, the strongest driver of cooperation is strong legal and institutional frameworks, which once established, form the basis for sustainable cooperation for water diplomacy between riparian states. Cooperation over the Okavango River Basin and the twenty years of cooperation established between Angola, Namibia and Botswana through the Permanent Cubango-Okavango River Basin Commission (OKACOM) highlights an optimistic account for hydro-political cooperation over trans-boundary water systems between sovereign riparian states and provides a useful model for water basin agreements that are yet to be established. This thesis thus concludes that in light of the growing challenges facing the water sector in Southern Africa, strong institutions and legal frameworks are required to enhance cooperation among riparian states.
316

Variable speed pumped storage plants multi-time scale control to allow its use to power system stability / Commande à multi échelle de temps de STEP à vitesse variable pour augmenter la stabilité du réseau électrique

Rodrigues Lima, Janailson 13 December 2017 (has links)
Le mixe énergétique du futur réseau électrique doit intégrer une grande quantité de source renouvelable intermittentes (RES). L’intermittence naturelle de ces sources sera,dans un premier moment, négligeable vis-à-vis de la stabilité du réseau électrique. Par contre,pour une large pénétration de RES, cette intermittence doit être intégrée à l'étude de la stabilité du réseau électrique. Pour une grande pénétration de RES à l'échelle européenne, un grand système de stockage d'énergie doit être mis en place. C'est déjà le cas aujourd'hui où les stations de transfert d'énergie par pompage(STEP) sont déjà utilisées. En effet, les STEP sont le moyen de stockage plus fiable et mature pour le stockage en haut puissance. Cependant,elles sont utilisées à ce jour, plutôt dans un cycle journalier et hebdomadaire d'équilibrage. La plupart des usines fonctionne de façon binaire(soit on, soit off) et ne participe pas à l'équilibrage du réseau électrique.Les nouvelles technologies envisagent de nouvelles utilisations pour les STEP. Les STEP à vitesse variable (Variable Speed PSP - de l'anglais Variable Speed Pumped Storage Plant)sont prévues de d'être utilisées en temps réel pour l'équilibrage du réseau électrique. L'objective de ce projet de ce projet est d'étudier les contributions de la STEP à vitesse variable à l'équilibrage du réseau électrique. Du point de vue du réseau, la STEP à vitesse variable est composée de deux systèmes en cascade séparés par les échelles de temps différentes. Le système peut réagir en 100ms avec la puissance nominale de la machine mais pour un temps limité (entre 5- 10s); le deuxième étage est le système hydraulique qui réagit moins vite (après 15s)mais qui peut tenir sa puissance pendant un longtemps (plusieurs heures). Ces différentes échelles de temps sont très importantes pour l'équilibrage du réseau électrique. Elles permettent que la STEP à vitesse variable soit utilisée pour différents problèmes d'équilibrage, mais comment l'utilisée reste encore un problème ouvert. Parmi d'autres,ce projet a comme objective répondre aux questions suivantes:Serait-il possible d'utiliser la STEP à vitesse variable pour l'équilibrage du réseau électrique à courant alternatif (AC) et/ou continu (DC)? Comment combiner, de façon intelligente, les réseaux continus à haute tension (HVDC - de l'anglais High Voltage Direct Current) et STEP à vitesse variable?Combinaison optimale de réaction rapide et lente pour équilibrer un réseau hybride AC et DC? La STEP à vitesse variable est-il un bon outil dynamique de stockage pour augmenter la capacité du réseau HVDC? Comment intégrer le contrôle d'une ligne HVDC et ce d'une STEP à vitesse variable?La STEP à vitesse variable peut atténuer les oscillations du réseau? / The future energy mix used toproduce electricity will include large shares ofrenewable energy sources (renewables). Theintrinsic time varying nature of these sourceswill be in the first a hinder to power systems'stability, but as their share will increase theypower of the machine but only for a limited time(typically 5 – 10 seconds); the second stage isthe hydraulic system that reacts slower (afterapprox. 15 seconds) but has a lot of energystored.These different time scales can be of uppermostUniversité Paris-SaclayEspace Technologique / Immeuble DiscoveryRoute de l’Orme aux Merisiers RD 128 / 91190 Saint-Aubin, Francemust be explicitly taken into account in thefuture when stabilizing the network. Forconstant use of renewables, in a Europe-widemanner, large storage will be capital. This isalready partially the case today, where pumpedwater storage is largely used. In fact waterstorage still is the most reliable and efficientstorage system for large amounts of power. Buttoday this is still mainly dedicated to findnight/day or weekly equilibrium of productionand consumption. These store plants are ratherplanned for an on/off utilization and do notparticipate on ancillary services (dynamicparticipation on the short term equilibrium of aninterconnection of systems or regions).New technologies allow envisaging new usesfor large storage systems. Variable SpeedPumped Storage Plants (Variable Speed PSP)are now expected to be used in real time toprovide ancillary services, effectivelyparticipating in the stabilization of powersystems. The objectives of this work are to studysome of these possibilities. It will look atdifferent aspects of stabilization: Variable SpeedPSP can be seen from the outside like a twostage systems in cascade that reacts with timeconstants that are one order of magnitude apart.The system can react within 100ms with ratedimportance when considering system's stability.They allow Variable Speed PSP to be used as thecontrol input for different stabilizationproblems, but how to do it is still an openproblem. Today these stations are only used asstandard storage, allowing the match ofproduction and consumption within a region ornetwork. The objective now is to study their useto further applications, and in particular, to studythe possibility of using them as one of the keycomponents of the future Multi-terminal HVDCnetworks. Several questions are open, this workaims to answer part of them:Is it possible to use Variable Speed PSP forancillary services (transient stability forexample) in AC and/or HVCD networks?How to combine in an intelligent way HVDCand Variable Speed PSP?Optimum combination of fast and slow reactionin order to stabilize a power grid that combinesDC and AC?Is Variable Speed PSP a good way to increasethe capability of HVDC by adding a verydynamic storage element?How to merge the control of the HVDC line andthe Variable Speed?Can this setup help to damp oscillations in thegrid?
317

Analysis of euoniticellus intermedius, larva gut micro-flora: potential application in the production of biofuels.

Mabhegedhe, Munamato 12 September 2012 (has links)
Recent years have seen a dramatic increase in first generation bio-fuel production, mainly driven by concerns of climate change and rising prices of transportation fossil fuels. Due to significant pressure on the few available food sources, second generation bio-fuels have entered the fray, as a sustainable alternative. This research‟s aim was to search for cellulolytic micro-organisms and enzymes from the gut of the dung beetle, Euoniticellus intermedius, (Coleoptera: Scarabaeida) that can be used in the production of second generation bio-fuels. Dung beetle larvae were dissected and the gut micro-flora cultured in cellulose medium. Bacterial growth and cellulase activity was monitored on a daily basis. DNA isolation was then done on the cellulose medium-cultured microbes and the isolated DNA cloned in E. coli. The clones were screened for cellulase activity using plate assays. A total of 7 colonies out of 160 screened colonies showed positive CMC (endo-β-1,4-glucanase) and MUC (cellobiohydrolase) activities. Sequencing of these positive colonies yielded mostly bacteria belonging to the Enterobacteriaceae family, most of which have not been previously reported to have cellulase activity. This study‟s findings prove that in addition to this dung beetle‟s gut being a fruitful source of microbial biodiversity, it is also a potential source of cellulolytic micro-organisms and enzyme activities that will aid the function and design of future bioreactors for the bio-fuel industry.
318

The implications of the rise of clean energy on lithium market dynamics

Jackson, Martin Robert January 2018 (has links)
A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Science in Engineering, Johannesburg 2018 / This research aims to assess the factors surrounding the emergence of markets with the greatest potential for rechargeable lithium battery adoption. The implications of the rise of electric vehicles and electrical energy storage are measured against lithium supply and market pricing. This was resolved by reviewing all available information and comparing it with the intricacies of resources, production and recycling. An analysis of price formation is also undertaken before making assumptions to enable a forecast of future market dynamics until 2030. Electric vehicles will require almost threefold the lithium produced in 2015 by the end of the period considered, with grid storage predicted to follow suit. No geological supply constraints were found, but economic scarcity is a strong possibility. Production is highly vulnerable to disruption due to concentration and the situation is exacerbated by inelastic demand. Recycling may be the most critical means of diversifying and improving supplies. / XL2019
319

L'influence du cinéma dans l'écriture romanesque de Marguerite Duras

Katinakis, Nicolina. January 2000 (has links)
No description available.
320

Déterminants de l'information reçue chez les femmes enceintes défavorisées au Québec

Sogbohossou, Codjo Paulin January 2001 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Page generated in 0.0492 seconds