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1
Odegaard, Leiv Erik. „Technological Step-Change in Industrial Production Systems“. Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for industriell økonomi og teknologiledelse, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25929.
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One of the most enduring issues in research on business strategy and organization is how firms can survive and achieve prosperity in the long run. A recurring answer to it is that firms must be ambidextrous: efficient in their conduct of today’s business while simultaneously being able to adapt to changes in the environment in the future. The recipe recommended to firms which strive for ambidexterity has often been to conduct two forms of innovation at the same time. Incremental innovations are smaller improvements in existing operations and must be pursued to enhance its efficiency. Radical innovations are concepts which are so new that they are incompatible with the existing organization and needed to stay ahead of and adapt to paradigm shifts in the technology and market. However, combining the pursuit of these innovations has proved difficult. The literature therefore suggests that they be carried out in separate organizational units, but the problem is then how firms can reap the synergies of them though integration. This thesis focuses on technological process innovation in industrial production systems. With this as a scope, it contributes to the understanding of ambidexterity in firms by exploring a new form of process innovation, technological step-change, which theoretically is positioned between incremental and radical innovation. Technological step-change is on one hand distinguished from radical innovation as it does not represent any shifts, but rather is related to the development of the existing production systems. On the other, it is distinguished from incremental innovation as it involves the introduction of new technological artifacts and larger, architectural changes in the system, and as such requires assistance from personnel with advanced technological knowledge. Based on a case study, a conclusion is that incremental innovations and step-changes reinforce each other and that the technology in step-changes has its origin in the radical innovation activities. Therefore, while the separated pursuits of incremental and radical innovations alone are largely independent of each other, technological step-changes form a link between the two and enable ambidexterity. It is furthermore found that step-changes are facilitated by the separation of incremental and radical innovation in distinct organizational units on one hand and integration with integrative mechanisms on the other.
2
Blanch, Roure Josep Salvador. „Changes in terpene production and emission in response to climate change and eutrophication“. Doctoral thesis, Universitat Autònoma de Barcelona, 2010. http://hdl.handle.net/10803/42003.
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80% of Volatile Organic Compounds (VOCs) that are emitted every year to the atmosphere come from biogenic sources (BVOCs), where many different families are included, such as isoprenoids. The production and emission of those compounds is influenced by environmental variables such as light and temperature. Those environmental variables will be affected by global change which has been predicted for the next decades.
The main objective of this thesis was to study the effect of global change, and specifically climate change, global warming and eutrophication, on isoprenoid, mono and sesquiterpene contents and emission rates. Moreover, we tested those effects in different families and genotypes, due to the intra and interespecific variability.
In order to answer those questions we carried out different experiments, from seminatural conditions to more controlled conditions (lab), because the more control of the environmental sampling parameters the better conditions to study isolated factors. Identification and quantification of both contents and emission was carried out using gas chromatography with mass spectrometry.
The main conclusions of the present thesis are: warming and drought increase both terpene content and emission independently of the specie (storing and non-storing species). However, different species responded differently to eutrophication: these responses depended on the species and on the sampling time. Finally, intra and interspecific differences where shown: different genotypes and different species behaved differently in both storing and non-storing species.Un 80% dels Compostos Orgànics Volaltils (COVs) que s’emeten anualment a l’atmosfera provenen de fonts biogèniques (COVBs), entre els que destaquen diferents famílies com per exemple els isoprenoids. La producció i emissió d’aquests compostos està influenciada per variables ambientals com la llum i la temperatura. Aquestes variables ambientals es veuran afectades pel canvi global que s’ha predit per les properes dècades. L’objectiu de la present tesi va estar estudiar l’efecte del canvi global i específicament canvi climàtic, escalfament i eutrofització, sobre el continguts i les emissions de les famílies isoprenoids, mono i sesquiterpens. A més, varem testar aquests efectes en diferents famílies i genotips, donades les variacions intra i interespecífiques. Per aconseguir resoldre aquestes preguntes varem realitzar diferents experiments, des de condicions seminaturals fins a condicions més controlades (de laboratori), on un major control de les condicions ambientals de mostreig permet estudiar efectes de forma aïllada. La identificació i quantificació dels compostons, tant continguts com emesos, es va fer mitjançant cromatografia de gasos i espectrometria de masses. Les principals conclusions d’aquesta tesis són: l’escalfament i la sequera van incrementar tant el contingut com les emissions de terpens en espècies acumuladores i en espècies no acumuladores. No obstant, les respostes de les diferents espècies a l’eutrofització van ser diverses, depenent de l’espècie i de les condicions ambientals del moment de mostreig. Finalment, es van constatar les diferències intra i interespecífiques: espècies diferents i genotips diferents es van comportar de diferent manera, tant en espècies acumuladores com en espècies no acumuladores.
3
Li, Hong. „Formatted entertainment in China : change in television production practices“. Thesis, University of Westminster, 2016. https://westminsterresearch.westminster.ac.uk/item/q0qz1/formatted-entertainment-in-china-change-in-television-production-practices.
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Since the format Got Talent achieved great success in China, we can see the prevalence of format adoption and the television industry’s reliance on western expertise. Television formats have provided Chinese television professionals not only with new creative inputs into indigenous production practices but also with license to experiment with ideas that may not fit in with the legacy of the national culture or the brand of the channel or network. This study explores the growing trend toward television format adoption and localization as an industry development strategy in China, and provides rich data through qualitative methods such as field observation and semi-‐structured interviews. The results of the various analyses in the thesis demonstrate, in different ways, how Chinese professionals perceive the development of their practices and that of the whole television industry following the adoption and localization of formats. Furthermore, the analyses also indicate how China’s political and economic contexts impact on the ways in which television formats are localized.
4
Zamchiya, Phillan. „Agrarian change in Zimbabwe : politics, production and accumulation“. Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:25e709cb-d621-47fa-a68e-db89ddacc3b3.
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The analysis of agrarian change presented in this thesis integrates state practices and wider politics to the study of rural differentiation, using a case study of Zimbabwe. Most studies of agrarian change in the 21st century have tried to come to grips with rural differentiation in Africa, its causes and effects, by using particular models such as those of neo-classical economics, livelihood approaches, Marxist analysis of accumulation and social and cultural networks, or a combination of variables from the four approaches. However, these theoretical approaches fail to comprehensively integrate the role of the state and politics into the analysis of rural differentiation. My study explains differentiation by exploring beneficiary selection, production and accumulation processes on Zimbabwe’s Fast Track land reform resettlement schemes. Fast Track involved a series of partisan and violent invasions of largely white owned commercial farms from 2000, which constituted the largest land redistribution in post-colonial Africa. Scholars exploring politics and the Zimbabwean state have not applied their insights to an analysis of field based data on production and accumulation on Zimbabwe’s resettlement farms. I argue that the restructuring of the state and politics as an instrument of violence and as a site of accumulation dominated by patronage-both justified through ideology-was central to agrarian change after 2000. I find the three concepts of violence, patronage and ideology more useful in capturing the nuances and modalities of empirical realities on resettlement schemes than neo-patrimonial theories that provide generalised accounts of the African state. Though still acknowledging the role of other differentiating factors such as social networks, hard work by resettled farmers and economic factors, it is through the integration of political processes into the analysis of agrarian change that, I argue, one can understand better the dynamics shaping rural differentiation in post-2000 Zimbabwe.
5
Du, Preez Cal. „Declining tobacco production : analysing key drivers of change“. Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60491.
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The size of the South African tobacco industry has been shrinking over the last 20 years. Tobacco production has decreased by 54% between 1990 and 2014. Along with the decline in the area of tobacco planted, the number of primary producers and tobacco processors have dwindled. South Africa serves as a case study to support the working committee for economically sustainable alternatives to tobacco growing (COP 6) in understanding the factors that impact producers exit decisions and the agricultural commodities that producers introduce once they leave tobacco production.
The Framework Convention on Tobacco Control seeks to find practical and cost effective control measures to reduce both the demand and supply of tobacco products. To achieve these ambitions, the working group for economically sustainable alternatives to tobacco growing was established. This working group seeks to understand all the elements of tobacco growing and the elements that drive the demand of alternative crops. The findings of this study supports the working group for economically sustainable alternatives to tobacco growing by providing insights on the factors that drive production and exit decisions. Additionally, it also identifies alternative crops that former tobacco producers have introduced. At the time of this study no literature detailed the effects of the restructuring of the South African tobacco industry. This study details the impact that the restructuring of the South African tobacco industry had on tobacco producers and their production decision. Globally no research existed on the factors that drive tobacco producers exit decisions and the enterprises that they have switched to after they left tobacco production.
This study investigates which agricultural commodities former producers have changed to and what impacted their decision to make this change. Although profitability was cited as the primary reason to leave tobacco production and to change to the production of another crop; only 18% of producers were making a loss with tobacco at the time of their exit from tobacco production. The study found that the profit margin realised on tobacco had declined when compared to other crops. Further investigation found that the profitability of tobacco was influenced by a number of variables, in particular low producer prices, the rising cost of inputs and the availability of alternative crops. Another factor that impacted producers tobacco production decision was co-operative politics this had a major impact on producers decision to leave tobacco production; not only had a number of former producers declined to participate in the survey because of co-operative politics but a number of current producers had left tobacco production during the restructuring of the South African tobacco industry. The events during the restructuring of the South African tobacco industry (the merger of three co-operatives and the closure of two co-operative owned processing facilities) created instability in the industry.
While investigating the alternative crops that producers had introduced, once they had left tobacco production or had diversified to while producing tobacco, it was found that there were regional differences in the agricultural commodities that were introduced and that there is no clear trend of the commodities that producers have introduced. Along with profitability other factors impacting producers' decisions to change to the production of an alternative agricultural commodity is detailed in the study.Dissertation (MCom)--University of Pretoria, 2016.
Agricultural Economics, Extension and Rural Development
MCom
Unrestricted
6
Andreoni, Antonio. „Manufacturing development : structural change and production capabilities dynamics“. Thesis, University of Cambridge, 2013. http://eprints.soas.ac.uk/19242/.
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Over the last three decades the political economy debate abandoned its focus on manufacturing as the main engine of the technological dynamism and the source of the wealth of nations. However recent years have witnessed a renewed interest in manufacturing production. This has led analysts to announce and welcome a worldwide 'manufacturing renaissance' emerging in different contexts with multiple focuses. The thesis provides new analytical and empirical lenses for disentangling the dynamics of manufacturing development. We do this by showing how learning processes are the fundamental category responsible for production capabilities dynamics which in turn trigger structural change. Essay 1 'The Manufacturing Renaissance: Transforming Industrial Systems and the Wealth of Nations' presents a novel synthesis of two strands of economic research, Structural Economic Dynamics and the Economics of Capabilities. Within this framework we integrate structural change and production capabilities dynamics. The following Essays of this dissertation apply and extend this theoretical synthesis by focusing firstly on learning in production structures and cumulative (non-linear) structural change dynamics (Essays 2 and 3 respectively); secondly, in developing new diagnostics for industrial policies design (Essay 4); finally, in investigating industrial policies for manufacturing development (Essay 5). Essay 2 'Structural Learning: Embedding discoveries and the dynamics of production' extends the current framework by rembedding learning dynamics from which production capabilities are generated in the production structure itself. Essay 3 'Manufacturing Agrarian Change. Agricultural production, intermediate institutions and Intersectoral commons: Lessons from Latin America' than applies the concept of structural learning developed in Essay 2 to the intersectoral interdependencies on the interface of agriculture and manufacturing. Moreover, we show how in the context of Chile and Brazil intersectoral learning from which intersectoral commons derive was facilitated by the development of intermediate institutions. Essay 4 'Production Capability Indicators. Mapping countries' structural trajectories and the assessment of industrial skills in LDCs: The case of Tanzania' addresses the problem of capturing these learning dynamics through production capabilities indicators at the national level. Not only do we propose a new theoretically-sensitive methodology for quantifying learning dynamics but also we apply this to industrial skills assessment in Tanzania. Finally, Essay 5 'Industrial Policy for Manufacturing Development. Structural dynamics and institutional changes in a dual economy: A case of dependent industrialisation in the Italian Mezzogiorno' focuses on the development of industrial policies, the latter understood as mechanisms to trigger learning dynamics at the sectoral and intersectoral level. The Italian 'Mezzogiorno' case is presented to illustrate these dynamics in a context of dependent industrialisation.
7
Koh, Chan Yang Edwin. „Managing change propagation in the development of complex products“. Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609499.
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8
Lööf, Kajsa. „Strategy for automation and layout change in production systems“. Thesis, KTH, Industriell produktion, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-61076.
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The main objective of this thesis is to identify changes in Level of Automation (LoA) and layout which are correlated. The thesis is aiming to contribute in the progressing research in automation with a practical aspect which is important to manufacturers. A case study was conducted at Parker Hannifin since research material from 2007 was available of this production system. Data from two different points in time is a necessity to observe any correlation in LoAand layout changes. The thesis is also meant to document the production system at Parker Hannifin. The research questions which will be attempted to answer are the two following: How does an increase of LoA affect the layout? Is there a specific point in the LoA where the layout changes dramatically? What improvements can be made to secure quality in Parker Hannifin’s production system? The DYNAMO methodology has been developed to measure and obtain an accurate picture of information flow and automation in production systems. The DYNAMO methodology uses a reference scale to measure LoA. This scale is divided into two parts, mechanical and cognitive, as both areas are considered when automating a production system. It proved to be an effective and objective technique to measure ParkerHannifin’s production system and data could be analyzed and compared to the previous study from 2007 ofthe same production system. The result from the case study at Parker Hannifin showed that the total LoA had increased and the layouthad changed, however the two alterations were not correlated. The Parker Hannifin case was further analyzed and one other experience from Sandvik was illustrated to draw the conclusion that there is a specific point in the LoA where the layout changes dramatically. (1) A mechanical LoA alteration betweenvalue 1 and 4 does not in itself involve a layout change. (2) Alterations in which LoA increases to 5, 6 or 7will most likely be followed by a layout change. Exactly how the increase of LoA affects the layout is hard to tell. Layout changes due to LoA are an issue of factory space and material flow. Since layouts should be compatible with current production systems, LoAchanges which infer in the production system might need a different space to be situated in, be it more space, less space or just a diverse positioning. Since cognitive LoA changes more frequently require equipment small in size, they are assumed to seldom cause layout changes. Recommendations that have been specifically stated to improve the production system at Parker Hannifin: Make DFA a standard procedure Workshop for designers and assemblers to collaborate Designers join assembly line for half a day for assembly system understanding Color coding of slides to eliminate mistakes Place instructions visibly for assemblers to easily access at all times to eliminate mistakes Using DFA at the developing stage for all valves is particularly important to minimize the costs and quality issues and ensure a smoother assembly.
9
Ngoma, Justine. „Effect on Climate Change on Maize Production in Zambia“. Thesis, Linköping University, Linköping University, Department of Water and Environmental Studies, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-16058.
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Maize is one of the crops that is grown by most farmers in Zambia being the staple food for the majority of Zambians. However, despite the crop being so important, its production is dependent on climatic conditions. This means that any change in climate can affect the production either negatively or positively. This research therefore, focused on determining how the change in temperature and rainfall affect maize production on the Copper belt, Eastern, Lusaka and Southern provinces of Zambia and investigate the main adaptation measures implemented by both the government and non-governmental sectors. Also, assess through the review of National Agricultural Policy and action plans, how the government has documented issues of climate change. In order to obtain the needed data, interviews were conducted with different officials from both the government and non-governmental sectors. However, from the estimate of the impact of temperature and rainfall on maize production, the results did not show with any significance that either temperature or rainfall has effect on maize production. In fact, it was found that quantifying the effects of climate change on maize production is not easy due to difficulties in quantifying other factors that may also have large impact on maize production. It was therefore, not possible to conclude whether or to what extent climate change has effects on maize production. However from the interviews conducted, it was found that both the government and non-governmental sectors have introduced different activities in their programmes to ensure that farmers are food secure, though the ministry of agriculture has no policy document on how to handle the problem of climate change to address different issues of the sector. In fact, most offices in the ministry do not have much documented information on climate change which could also be seen from the review of National Agricultural Policy and action plans where climate change issue has not been emphasized. Though both the Government and non-governmental sectors have implemented some adaptation measures, it cannot easily be concluded whether the implemented measures are adequate or not due to the fact that we are not sure of the expected effects in different parts of the country. Nevertheless, to enhance food security with or without adverse effects of climate change on maize production, it was recommended that members of staff at all levels under MACO should be trained in the area of climate change for them to have a wider understanding of the issue and work responsively and that much research should be done to open up the mind of the people and help policy makers make effective plans.
10
Msowoya, Kondwani. „Climate Change Impacts on Rainfed Corn Production in Malawi“. Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5992.
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Agriculture is the mainstay of the economy in Malawi and accounts for 40% of the Gross Domestic Product (GDP) and 90% of the export revenues. Corn (maize) is the major cereal crop grown as staple food under rainfed conditions, covers over 92% of the total agricultural area, and contributes 54% of the caloric intake. Corn production is the principle occupation and major source of income for over 85% of the total population in Malawi. Issues of hunger and food insecurity for the entire nation are associated with corn scarcity and low production. Global warming is expected to cause climate change in Malawi, including changes in temperature and precipitation amounts and patterns. These climate changes are expected to affect corn production in Malawi. This study evaluates the impacts of climate change on rainfed corn production in Malawi. Lilongwe District, with about 1,045 square miles of agriculture area, has been selected as a representative area. First, outputs of 15 General Circulation Models (GCMs) under different emission scenarios are statistically downscaled. For this purpose, a weather generator (LARS-WG) is calibrated and validated for the study area and daily precipitation as well as minimum and maximum temperature are projected for 15 GCMs for three time horizons of 2020s, 2050s and 2090s. Probability assessment of bounded range with known distributions is used to deal with the uncertainties of GCMs' outputs. These GCMs outputs are weighted by considering the ability of each model to simulate historical records. AquaCrop, a new model developed by FAO that simulates the crop yield response to water deficit conditions, is employed to assess potential rainfed corn production in the study area with and without climate change. Study results indicate an average temperature increase of 0.52 to 0.94oC, 1.26 to 2.20oC and 1.78 to 3.58oC in the near-term (2020s), mid-term (2050s) and long-term (2090s) future, respectively. The expected changes in precipitation during these periods are -17 to 11%, -26 to 0%, and -29 to -3%. Corn yields are expected to change by -8.11 to 0.53%, -7.25 to -14.33%, and -13.19 to -31.86%, during the same time periods. The study concludes with suggestion of some adaptation strategies that the Government of Malawi could consider to improve national food security under climate change.M.S.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering; Water Resources Engineering
11
Filipe, Derek Anthony. „Energy change detection to assist in tactical intelligence production“. Thesis, Monterey, Calif. : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Jun/09Jun%5FFilipe.pdf.
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Thesis (M.S. in Systems Technology (Command, Control, and Communications) and M.S. in Space Systems Operations)--Naval Postgraduate School, June 2009.Thesis Advisor(s): Pfeiffer, Karl D. ; Bursch, Dan W. "June 2009." Description based on title screen as viewed on July 13, 2009. DTIC Identifiers: Energy change detection, ECD (Energy Change Detection), SIGINT (Signals Intelligence), Global War on Terror, information theory. Author(s) subject terms: Tactical Intelligence, Leavitt's Diamond, OODA Loop, Kendall's Notation, Global War on Terror (GWOT), Energy Change Detection, Information Theory, Information Entropy. Includes bibliographical references (p. 79-80). Also available in print.
12
Bunn, Christian. „Modeling the climate change impacts on global coffee production“. Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2015. http://dx.doi.org/10.18452/17349.
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Die Untersuchung der Auswirkungen des Klimawandels auf die globale Kaffeeproduktion in einem integriertem Modell war das Ziel dieser Arbeit. Der vorwiegende Teil der globalen Kaffeeproduktion stammt von zwei Arten: dem hitzeempfindlichen Coffea arabica (Arabica) Strauch und vom frostempfindlichen Coffea canephora (Robusta). Eine zunehmende Zahl Studien zeigt, dass der Klimawandel bereits heute die Produktion mindert. Maschinenlernklassifizierung wurde hier genutzt um ein Modell der globalen Klima-Kaffee-Wechselwirkungen zu entwickeln. Zur Integration der modellierten Klimafolgen mit ökonomischen Faktoren war ein detailliertes Wissen über die räumliche Verteilung der Kaffeeproduktion notwendig. Da existierende Datensätze unzureichend waren, wurde ein neuer methodischer Ansatz auf der Grundlage der maschinenlern-basierten Anbaueignungsklassifizierung entwickelt. Diese beiden Schritte waren Voraussetzung für die Inklusion eines Modells des Kaffeesektors in dem räumlich expliziten partiellen Gleichgewichtsmodell Globiom. Auf der Hälfte der heute für den Anbau geeigneten Fläche muss bis 2050 2,5-mal so viel Kaffee produziert werden um die zukünftige Nachfrage zu sättigen. Niedrigere Ernten und höhere Preise werden das Volumen des Kaffeemarktes um über 5 Mio. Tonnen pro Jahr reduzieren. Dieser Verlust entspricht dem Marktvolumen im Modellbasisjahr. Kaffeeproduktion wird zukünftig in höheren Lagen angebaut werden müssen, sofern dort landwirtschaftliche Fläche zur Verfügung steht. Die Produktion wird größtenteils innerhalb der gegenwärtigen Breitengrade bleiben, aber wichtige Produzenten, wie Brasilien und Vietnam werden Probleme haben wettbewerbsfähig zu bleiben mit weniger betroffenen Ländern in Ost-Afrika. Modellunsicherheit auf lokaler Ebene erschwert jedoch die Entwicklung eindeutiger Anpassungsempfehlungen. Es wird also auch in Zukunft Kaffee geben, aber dieser Kaffee wird von geringerer Qualität sein und mehr kosten.To model the impacts of climate change on global coffee production in an integrated modeling framework was the objective of this thesis. The majority of coffee is produced using either one of two species which form a single market: the heat sensitive Coffea arabica (Arabica) and the cold sensitive Coffea canephora (Robusta). Recently, evidence is increasing that climate change has begun to affect production. Machine learning classification was used to develop a global biophysical impacts model for both coffee species. Integrating these biophysical effects with demand side effects required a detailed understanding of the spatial distribution of coffee production. Because existing datasets were found to be insufficient a novel methodology was developed that built upon the machine learning classification of coffee suitability. These two steps were preconditions to include a model of the coffee sector in the spatially explicit partial equilibrium modeling framework Globiom. On only half the area that is currently available for coffee production by 2050 2.5-times as much coffee will have to be produced to meet future demand. Reduced yields and increased prices were shown to reduce the coffee market by more than 5million tons per year, equivalent to the size of the baseyear market volume. Coffee production will migrate to higher elevations where area is available for agricultural production. Production will remain within current latitudinal ranges but major producers like Brazil and Vietnam will struggle to remain competitive with relatively less affected countries in East Africa. Substantial uncertainty about the impacts on local scale prevails and impedes the development of unambiguous adaptation strategies. Thus, there will be coffee on the table in 2050, but it will be of lower quality and will cost more.
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Mulhall, Rachel Ann. „Manufacturing change : competitiveness and adjustment through evolving production relationships“. Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4046/.
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Manufacturing is a vital and significant element of the British economy. The sector has made a transition towards the production of higher value-added products and services to remain competitive in increasingly international markets. A highly skilled and competitive supply base is central to the viability of the sector as tasks once undertaken by end-manufacturers are increasingly being absorbed into the portfolio of functions undertaken by the supplier. This thesis examines how one supply industry, intermediate metal processing (IMP), is adjusting to international competition in the context of increasingly complex dependencies in the supply chain. An intensive study of IMP manufacturers in the West Midlands (UK) was undertaken through qualitative interviews and desk based research to understand the current challenges and opportunities the industry faced. The analysis is focused on the transition to higher value manufacturing and the complexity of buyer-supplier relationships. This is developed through a case study analysis of the industry’s adjustment to rising industrial energy costs and a detailed examination of customer agreement structures in shaping transactional governance structures. The research makes a contribution to current conceptions of the spatial organisation of production and the nature of production relationships. Mature industries, such as metal component manufacture, are successfully undertaking complex and varied forms of adaptation to remain competitive. Despite transitions to value-added products, costs continue to be an important element to both competitiveness and viability. Production relationships, and specifically the nature of the inter-firm agreement, are a significant aspect of adjustment and the capacity to capture value through governance mechanisms. Contracts are a relatively under represented factor of inter-firm relationships but are found to be central to the adaptability of firms, the attainment of value and stability of the business.
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Mqadi, Lwandle. „Production function analysis of the sensitivity of maize production to climate change in South Africa“. Diss., Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-02132006-083959.
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Lawrence, Daniel. „Sound change and social meaning : the perception and production of phonetic change in York, Northern England“. Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31327.
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This thesis investigates the relationship between social meaning and linguistic change. An important observation regarding spoken languages is that they are constantly changing: the way we speak differs from generation to generation. A second important observation is that spoken utterances convey social as well as denotational meaning: the way we speak communicates something about who we are. How, if at all, are these two characteristics of spoken languages related? Many sociolinguistic studies have argued that the social meaning of linguistic features is central to explaining the spread of linguistic innovations. A novel form might be heard as more prestigious than the older form, or it may become associated with specific social stereotypes relevant to the community in which the change occurs. It is argued that this association between a linguistic variant and social meaning leads speakers to adopt or reject the innovation, inhibiting or facilitating the spread of the change. In contrast, a number of scholars have argued that social meaning is epiphenomenal to many linguistic changes, which are instead driven by an automatic process of convergence in face-to-face interaction. The issue that such arguments raise is that many studies proposing a role of social meaning in the spread of linguistic innovations rely on production data as their primary source of evidence. Observing the variable adoption of innovations across different groups of speakers (e.g. by gender, ethnicity, or socioeconomic status), a researcher might draw on their knowledge of the social history of the community under study to infer the role of social meaning in that change. In many cases, the observed patterns of could equally be explained by the social structure of the community under study, which constrains who speaks to whom. Are linguistic changes facilitated and inhibited by social meaning? Or is it rather the case that social meaning arises as a consequence of linguistic change, without necessarily influencing the change itself? This thesis explores these questions through a study of vocalic change in York, Northern England, focusing on the fronting and diphthongization of the tense back vowels /u/ and /o/. It presents a systematic comparison of the social meanings listeners assign to innovations (captured using perceptual methods), their social attitudes with regard to those meanings (captured through sociolinguistic interviews), and their use of those forms in production (captured through acoustic analysis). It is argued that evidence of a consistent relationship between these factors would support the proposal that social meaning plays a role in linguistic change. The results of this combined analysis of sociolinguistic perception, social attitudes and speech production provide clear evidence of diachronic /u/ and /o/ fronting in this community, and show that variation in these two vowels is associated with a range of social meanings in perception. These meanings are underpinned by the notion of 'Broad Yorkshire' speech, a socially-recognized speech register linked to notions of authentic local identity and social class. Monophthongal /o/, diphthongal /u/, and back variants of both vowels are shown to be associated with this register, implying that a speaker who adopts an innovative form will likely be heard as less 'Broad'. However, there is no clear evidence that speakers' attitudes toward regional identity or social class have any influence on their adoption of innovations, nor that that their ability to recognise the social meaning of fronting in perception is related to their production behaviour. The fronting of /u/ is spreading in a socially-uniform manner in production, unaffected by any social factor tested except for age. The fronting of /o/ is conditioned by social network structure - speakers with more diverse social networks are more likely to adopt the innovative form, while speakers with closer social ties to York are more likely to retain a back variant. These findings demonstrate that York speakers hear back forms of /u/ and /o/ as more 'local' and 'working class' than fronter realizations, and express strong attitudes toward the values and practices associated with regional identity and social class. However, these factors do not appear to influence their adoption of linguistic innovations in any straightforward manner, contrasting the predictions of an account of linguistic change where social meaning plays a central role in facilitating or inhibiting the propagation of linguistic innovations. Based on these results, the thesis argues that many linguistic changes may spread through the production patterns of a speech community without the direct influence of social meaning, and advocates for the combined analysis of sociolinguistic perception, social attitudes and speech production in future work.
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Deraniyagala, Sonali. „Technical change and efficiency in Sri Lanka's manufacturing sector“. Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307408.
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Cox, Amy M. „Functional Gain and Change Mechanisms in Post-Production Complex Systems“. Thesis, The George Washington University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10254316.
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This research was motivated by the need for functional change of complex systems in post-production. Through an initial empirical study, this research found pathways to functional change with minimal change to form; thus avoiding the high risk of material change propagation that has been a concern of both the systems engineering and engineering change literature. This study also revealed the relative importance of system users in the post-production change environment. Through a follow-on study of user innovation in this environment this research was able to reveal pathways for change which are underexplored in both the user innovation and flexibility literature.
While not yet a final solution to the motivating problem, this research has revealed levers for change which system users are adept at exploiting. Key amongst the changes employed by user designers is their unconstrained use of themselves (human change) to realize system function and their exploitation of the expansive operational states (operational change) afforded by complex systems. User driven change poses an important source of post-production functional change. This research unpacks user change and sets the stage for further investigation of this source of system changeability.
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Hedström, Per. „Climate change impacts on production and dynamics of fish populations“. Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-128007.
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Ongoing climate change is predicted to increase water temperatures and export of terrestrial dissolved matter (TDOM) to aquatic ecosystems influencing ecosystem productivity, food web dynamics and production of top consumers. Ecosystem productivity is mainly determined by the rates of primary production (GPP) in turn controlled by nutrients, light availability and temperature, while temperature alone affect vital rates like consumption and metabolic rates and maintenance requirements of consumers. Increased level of TDOM causes brownification of water which may cause light limitation in algae and decrease GPP and especially so in the benthic habitat. Temperature increase has a been suggested to increase metabolic rates of consumers to larger extent than the corresponding effect on GPP, which suggest reduced top consumer biomass and production with warming. The aim of this thesis was to experimentally study the effects of increased temperature and TDOM on habitat specific and whole ecosystem GPP and fish densities and production. In a replicated large-scale pond experiment encompassing natural food webs of lotic ecosystems I studied population level responses to warming and brownification in the three- spined stickleback (Gasterosteus aculeatus). Results showed overall that warming had no effect on whole ecosystem GPP, likely due to nutrient limitation, while TDOM input decreased benthic GPP but stimulated pelagic GPP. In fish, results first of all suggested that recruitment in sticklebacks over summer was negatively affected by warming as maintenance requirements in relation to GPP increased and thereby increased starvation mortality of young-of-the-year (YOY) sticklebacks. Secondly, brownification increased mortality over winter in YOY as the negative effect on light conditions likely decreased search efficiency and caused lower consumption rates and starvation over winter in sticklebacks. Third, seasonal production of YOY, older, and total stickleback production was negatively affected by warming, while increased TDOM caused decreased YOY and total fish production. The combined effect of the two was intermediate but still negative. Temperature effects on fish production were likely a result of increased energy requirements of fish in relation to resource production and intake rates whereas the negative effect of TDOM likely was a result of decreased benthic resource production. Finally, effects of warming over a three-year period caused total fish density and biomass and abundance of both mature and old fish to decrease, while proportion of young fish increased. The main cause behind the strong negative effects of warming on fish population biomass and changes in population demographic parameters were likely the temperature driven increased energy requirements relative to resource production and cohort competition. The results from this thesis suggest that predicted climate change impacts on lentic aquatic ecosystems will decrease future densities and biomass of fish and negatively affect fish production and especially so in systems dominated by benthic resource production.
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Thanke, Wiberg Joakim. „Local Impacts of Climate Change on Fortum´s Hydropower Production“. Thesis, KTH, Vattendragsteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183396.
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Background: Climate change and the consequences of global warming is probably one of the greatest issues of our time. Among other concerns, global warming is thought to have a great impact on hydrology worldwide. When the atmosphere warms up, river runoff patterns are altered. Nevertheless these future changes are assumed to increase the hydropower potential in some countries. In the public debate it is often referred to a nine year old investigation claiming an increase of 15-20 % in Swedish energy production from hydropower due to the river runoff increase. On the other hand recent research is hinting that the effect of global warming might be masked by climate variability in the nearest future. This study seeks to investigate whether or not the hydropower-intensive company Fortum will benefit from increased future hydropower potential due to climate change. Methods: Using historical data, the impacts of global warming on the future potential power production in different types of hydropower plants are estimated by the statistical approach of probability density functions. Moreover spectral analysis is used to investigate the impacts of climate variability in various Swedish watersheds. The study investigates both the nearest future, represented by the years 2021-2050, and the end of the century, represented by the years 2069-2098. Results: The future hydropower production is shown to be strongly dependent on the geographical location of a power plant and of the specific power plant type. Although all Swedish rivers where Fortum operates is given more river runoff in the future, some hydropower plants might suffer from lower hydropower potential due to increased runoff variability. However all reservoir-type power plants in the study, with ability to store water, are calculated to benefit from increased river runoff. Only the run-of-river type power plants, operating with unregulated river flow, are not yet proven to benefit from a changing climate. When considering both specific river and type of power plant, this study indicates that the hydropower potential in the rivers where Fortum operates is expected to increase with 4-15 % towards the end of the century. The one exception is the unregulated river Västerdalälven where this study indicates a possibility of decreased hydropower potential due to climate change. The results of the spectral analysis indicates that up to 30 % of the coefficient of variation in the monthly mean runoff data is explained by low-frequent periodic fluctuations due to natural climate variability, linked to somewhat predictable climate indices. Conclusion: Natural climate variability is likely to be the dominating factor in the nearest future, at least in regulated rivers. Although there are uncertainties about the future potential power production in the run-of-river type power plants, one cannot deny that most of the Swedish rivers where the major hydropower companies operate are strongly regulated. Adding the fact that river runoff will increase as a consequence of global warming, Fortum is likely to gain from an increased hydropower potential. However, this present study highlights the inaccuracies in using the out-of-date estimation of 15-20 % hydropower-potential increase as a forecast of future potential power production in all Fortum-operated hydropower plants.
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MacIntosh, Malcolm Leslie. „The management of change in four manufacturing organizations“. Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phm15188.pdf.
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Bibliography: leaves 350-402. This thesis is concerned with the process of change and adaptation in four Australian manufacturing companies in the period 1989 to 1996. The thesis seeks to explain the reaction of these companies to the pressures for change, and particularly for the adoption of 'best practice' management prescriptions in the organization of work and human resource management. The operating hypothesis adopted is that the pattern of changes undertaken by manufacturing organizations are shaped by a variety of factors both external to and within the company, but that management beliefs and orientations are a key element in understanding the pace and extent of change. The research is pursued through detailed case studies designed to explore at length pressures for change and continuity in corporate decision-making.
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Obioha, EE. „Climate variability and food production Nexus in Lesotho, 2001 - 2007“. Journal of Human Ecology, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001181.
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ABSTRACT In the recent times, due to the increasing rate of global warming, the Southern African region, especially,
Lesotho has been experiencing continuous climatic change characterized by drastic reduction in rainfall, increase in
the rate of dryness and heat, with depletion of the amount of water, flora and fauna resources. The situation has been
so for years without many questions and answers with regard to how it affects food production and security in the
country. Against this background, this paper investigates the chain of interactions between climatic change, expressed
in the rate of rainfall and drought condition, the indigenous adaptation mechanisms and food production in Lesotho.
The paper addresses the estimate of drought condition in Lesotho, Southern Africa, the nature of food production
activities in the area and the extent to which continuous climatic change has affected the state of food production.
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Becker, Stephen Lewis. „Re-thinking the educational production function paradigm /“. Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Llort, Jordi Joan. „Bloom phenology, mechanisms and future change in the Southern Ocean“. Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066064.
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La production primaire (PP) dans l'Océan Austral joue un rôle crucial dans la capacité des océans à absorber le carbon atmosphérique. Elle est caractérisée par une forte limitation en Fer et par un cycle saisonnier très marqué, présentant un bloom planctonique en fin d'hiver, plus ou moins intense selon les régions. Ma thèse est centrée sur la compréhension des mécanismes qui contrôlent ce bloom et sa variabilité, ainsi que sur les éléments, présents et futurs, qui contrôlent son intensité. J'ai abordé le premier aspect (phénologie et mécanismes) en mettant en place une approche mécaniste basée sur une nouvelle configuration du modèle biogéochimique PISCES forcé par un environnement physique 1D idéalisé. Cette méthodologie m'a permis de réconcilier les différentes théories sur la formation des blooms aux hautes-latitudes, d'identifier les spécificités du bloom de l'Océan Austral et de proposer des critères adaptés à sa détection dans les observations. En outre, les résultats de cette étude de modélisation ont été confrontés à ceux issues d'une deuxième approche, basée sur des observations satellitaires, ce qui a permis la localisation géographique des différentes phénologies de bloom que j'ai identifiées dans l'Océan Austral. Pour répondre au deuxième aspect (altération et changements futurs), j'ai également suivi une double approche. J'ai d'abord examiné comment les limitations par la lumière et par le fer se combinent, via la variabilité du cycle saisonnier du mélange vertical, et pilotent ainsi la production primaire dans l'Océan Austral actuel à l'aide de la configuration idéalisée présentée plus haut. Dans un deuxième temps, cette analyse a permis d'aider à l’interprétation des variations de PP observées dans les projections climatiques issues de 8 modèles couplés (CMIP5). L'ensemble de mes résultats permet de mieux comprendre les processus physiques et biologiques qui contrôlent la croissance du phytoplancton dans l'Océan Austral et d'appréhender comment la modification de ces processus peut entraîner des altérations de la PP dans une région clé pour l'évolution future du climatPrimary production (PP) in the Southern Ocean (SO) plays a crucial role on atmospheric carbon uptake. PP in this ocean is highly iron-limited and presents a marked seasonal cycle. Such a seasonal cycle has a strong productive phase in late winter, called bloom, which distribution and intensity is highly variable. My PhD focus on two specific aspects of the PP in the SO: first, the mechanisms that drive such a bloom and its dynamics and, second, the elements able to control the bloom intensity at present and in the future. The first aspect (bloom phenology and mechanisms) was addressed by setting up a mechanistic approach based on a novel model configuration: a complex biogeochemical model (PISCES) forced by a 1D idealised physical framework. This methodology allowed me to conciliate the different bloom formation theories and to identify the SO bloom specificities. Moreover, I proposed how to use different bloom detection criteria to properly identify bloom from observations. Such criteria were then tested in a complementary observation-based approach (with satellite and in-situ data) to characterise different bloom phenologies and its spatial distribution in the SO. The second aspect (bloom intensity and future change) was also addressed by a twofold approach. First, using the 1D model, I studied how seasonal variability of vertical mixing combine light and Fe limitation to drive PP. Secondly, I used such an analysis to interpret PP trends observed in 8 coupled model climatic projections (CMIP5 models). My PhD thesis results allow for a better understanding of the physical and biological processes controlling phytoplankton growth. My conclusions also suggest how an alteration of these processes by Climate Change may influence PP in the whole SO, a key region for future climate evolution
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Hoffmann, Holger [Verfasser]. „Abiotic impact of regional climate change on horticultural production / Holger Hoffmann“. Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2013. http://d-nb.info/1047351730/34.
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Almaraz, Suarez Juan Jose. „Climate change and crop production in southwestern Quebec : mitigation and adaptation“. Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103364.
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Anthropogenic greenhouse gas emissions are the main cause of increasing global temperatures. Climate change will affect crop production in Canada and, in turn agriculture has the potential to mitigate climate change. Analysis of historical climate and corn yield data, and field and greenhouse experiments were carried out in order to study the effect of climate variability and changes on corn yield, the adaptability of cropping systems to climate change conditions, the effect of tillage on soil greenhouse gas emissions (CO2 and N2O) associated with corn and soybean production, and the potential of Nod factors to increase biomass as way to mitigate CO2 emissions. In southwestern Quebec, corn yield variability has been strongly associated to July temperature and May precipitation during the last three decades. Field studies showed that switchgrass and sorghum-sudangrass were best adapted to dry and warm climate events. No-till improved corn yield when spring temperatures were warmer than normal. Soil CO2 fluxes were associated with temperature, while soil N2O fluxes were associated with precipitation. Conventional tillage (CT) had greater CO2 emissions than no-till (NT), particularly after disking in the spring. Both tillage systems had large N2O emission peaks during the wettest part of the season. In corn, peaks of N 2O occurred after nitrogen fertilizer application. NT had greater N 2O emissions than CT in the corn production systems; however, CT had greater N2O fluxes than NT in the soybean production system. Nod factors sprayed on soybean increased photosynthesis and biomass under controlled conditions. In the field, yield was increased by Nod factors under CT, but not under NT, and drought reduced the soybean response to Nod factors.Les émissions anthropogènes de gaz à effet de serre sont la cause principale de l'augmentation globale des températures. Les changements climatiques vont affecter la production agricole au Canada, et en retour, l'agriculture pourrait limiter les changements climatiques. L'analyse de données historiques du climat et des rendements de maïs, combinés avec des expériences de serre et en champ ont été entreprises pour étudier l'effet de la variabilité et des changements de climat sur le rendement de maïs, l'adaptabilité des systèmes agricoles aux changements climatiques, l'effet du travail du sol sur les émissions de gaz à effet de serre (C02 et N20) associées avec la production de maïs et de soya, et le potentiel des facteurs Nod d'augmenter la biomasse pour limiter les émissions de CO2. L'analyse des données historiques ont démontré qu'au sud-ouest du Québec, la variabilité des rendements de maïs est fortement associée avec les températures de juillet et les précipitations de mai pendant les dernières trois décennies. Les expériences au champ ont démontré que le panic raide, et le sorghum-sudangrass sont les mieux adaptés aux conditions chaudes et sèches. Le semis direct a augmenté les rendements de maïs lorsque les températures printanières étaient plus chaudes que la normale. Les flux de C02 étaient associés avec la température, mais les flux de N20 étaient associés avec les précipitations. Le travail du sol conventionnel (CT) a produit plus d'émissions de CO2 que le semis direct (NT), particulièrement après le disquage au printemps. Les deuxsystèmes ont montré un large pic d'émission de N20 pendant les périodes les pluspluvieuses. Dans le maïs, les pics de N20 ont été détectés après la fertilisation enazote. NT a montré des émissions de N20 plus importantes que CT en productionde maïs, mais CT a montré des flux de N20 plus important que NT en productionde soya. Les facteurs Nod vaporisés sur le soya ont augmenté la photosynthèse etla biomasse sous conditions controllées. Au champ, le rendement a été augmentépar les facteurs Nod sous CT, mais pas sous NT, et la sécheresse a réduit laréponse du soya aux facteurs Nod.
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Harris, Cory Dalton. „Organizational change and intellectual production the case study of Hohokam archaeology /“. Tucson, Ariz. : University of Arizona, 2006. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu%5Fetd%5F1489%5F1%5Fm.pdf&type=application/pdf.
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Harris, Cory. „Organizational Change and Intellectual Production: The Case Study of Hohokam Archaeology“. Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/195990.
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Histories of archaeology increasingly focus on the role that the social context of the discipline plays in shaping its intellectual production. Of particular importance in the social context of American archaeology during the last half of the 20th century is the development of Cultural Resource Management (CRM) archaeology. The coalescence of the CRM industry has transformed archaeology--providing new sources of support, mandating new goals, and placing practitioners into newly emergent organizational environments. Drawing upon theory in the sociology of science, this project examines the case study of the recent history of Hohokam--archaeological label for the agricultural people of southern Arizona--archaeology, which has been shaped by CRM more than any other region in the United States. According to sociological expectations, such a dramatic change in the social setting of the discipline should be reflected in its intellectual production.This dissertation documents patterns of intellectual production within Hohokam archaeology over the past century through both qualitative and quantitative means. In addition to providing a recent historical account of the region's archaeological community, this project utilizes a range of citation analyses to elucidate patterns in a manner relatively independent of subjective assessments of the character of Hohokam discourse.The analyses suggest that the changing organizational structure of Hohokam archaeology has impacted its basic intellectual structure. Changing patterns evident in both academic and CRM publications parallel reconfigurations in the social context of the region's archaeology. These findings offer substance for discussions of how archaeology should conduct itself in the face of changing organizational environments to ensure that the discipline continues to achieve its primary goal--the construction of knowledge about the past--in productive and intellectually rewarding ways.
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Harrison, Paula A. „Climate change and wheat production : spatial modelling of impacts in Europe“. Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310423.
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Arias, Pedro M. „Efficiency and technical change in milk production in north-west Uruguay“. Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298483.
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Blight, Stephen Warner Carleton University Dissertation Geography. „Pastoral production and change; pastoralists, development and the state in Kenya“. Ottawa, 1986.
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Tingem, Munang Richard. „The potential impacts of climate change on agricultural production in Cameroon“. Thesis, University of Nottingham, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.519391.
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Harbour, Tiffany Kwader. „Evaluation of the Brazilian Agrarian Reform Objective: Agricultural Production Yield Change“. ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3247.
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Brazil has an active agrarian reform policy program, publicly organized by the federal government and publicly administered at the state level by the National Institute for Colonization and Agrarian Reform. The objective of the agrarian reform policy program is to retitle unproductive and underproductive rural lands to increase agricultural production and land use. Previous agrarian reform researchers have examined quantities of land redistributed, rural technology developments, and the impact of social movements on land redistribution, but a knowledge gap remains regarding the correlation of agricultural production yields in rural municipalities before and after policy program participation. The State of Ceará has undertaken continuous land redistribution efforts between 1975 and 2006. For this longitudinal study, an agricultural production yield t-test analysis was conducted for the Brazilian State of Ceará with the marked time-series data collection for 1990, 1996, 2000, and 2006. The research and evaluation of the agrarian reform policy program used publicly available, secondary data from the Government of Brazil's Brazilian Institute of Geography and Statistics and the National Institute of Colonization and Agrarian Reform. The correlated analysis was organized by group: municipalities with a high-rate of agrarian reform participation and municipalities with a no-rate level of agrarian reform participation. By marking the point of program participation at 1996, the time-series t test identified marked agricultural production increases as correlated to agrarian reform policy program participation. The results can be used to justify agrarian reform programs, to promote further rural infrastructure development, and to support poverty alleviation efforts.
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Smith, Bridget J. „The Interaction of Speech Perception and Production in Laboratory Sound Change“. The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374116504.
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Ove, Peter. „“Change a life. Change your own” : child sponsorship, the discourse of development, and the production of ethical subjects“. Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44164.
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This project explores the practice of child sponsorship and its role in helping construct ethical subjectivities in the North. Employed by organizations like World Vision and Plan International, child sponsorship is one of the most prominent and successful fundraising techniques for development efforts in the global South. Child sponsorship is more than an effective marketing tool, however; it is a powerful apparatus for the conveyance of representations about the global South, the North, and the relationship between the two. Using a discourse analytic approach, this project examines Canadian sponsorship programs, the advertising they produce, and sponsors they attract. This analysis addresses not only the representations contained within sponsorship promotional material but also the contexts in which this material is produced, interpreted, and acted upon.
Drawing on in-depth interviews with 31 child sponsors and 18 sponsorship staff, this research explores how sponsorship programs and sponsors are represented – and represent themselves – as trying to “make a difference” in the world, and how these representations relate to contemporary understandings of poverty and development. In the end, it is argued that the success of child sponsorship is not related as much to the way it focuses on the needs of poor children as it is to the way it constructs a vision of ethical action in the work of international development that coincides with the personal development of Northern sponsors, the “natural” bio-psychological development of Southern children, and the organizational development of sponsorship programs. In other words, child sponsorship and its advertizing (re)positions what it means to live ethically in an unequal and unjust world. Through child sponsorship, the desires to become better people(s), secure appropriate childhoods, and raise lots of money end up taking priority over the goal of living together well on a global scale.
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Haouas, Nabiha. „Wind energy analysis and change point analysis“. Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22554.
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L’énergie éolienne, l’une des énergies renouvelables les plus compétitives, est considérée comme une solution qui remédie aux inconvénients de l’énergie fossile. Pour une meilleure gestion et exploitation de cette énergie, des prévisions de sa production s’avèrent nécessaires. Les méthodes de prévisions utilisées dans la littérature permettent uniquement une prévision de la moyenne annuelle de cette production. Certains travaux récents proposent l’utilisation du Théorème Central Limite (TCL), sous des hypothèses non classiques, pour l’estimation de la production annuelle moyenne de l’énergie éolienne ainsi que sa variance pour une seule turbine. Nous proposons dans cette thèse une extension de ces travaux à un parc éolien par relaxation de l’hypothèse de stationnarité la vitesse du vent et la production d’énergie, en supposant que ces dernières sont saisonnières. Sous cette hypothèse la qualité de la prévision annuelle s’améliore considérablement. Nous proposons aussi de prévoir la production d’énergie éolienne au cours des quatre saisons de l’année. L’utilisation du modèle fractal, nous permet de trouver une division ”naturelle” de la série de la vitesse du vent afin d’affiner l’estimation de la production éolienne en détectant les points de ruptures. Dans les deux derniers chapitres, nous donnons des outils statistiques de la détection des points de ruptures et d’estimation des modèles fractalsThe wind energy, one of the most competitive renewable energies, is considered as a solution which remedies the inconveniences of the fossil energy. For a better management and an exploitation of this energy, forecasts of its production turn out to be necessary. The methods of forecasts used in the literature allow only a forecast of the annual mean of this production. Certain recent works propose the use of the Central Limit Theorem (CLT), under not classic hypotheses, for the estimation of the mean annual production of the wind energy as well as its variance for a single turbine. We propose in this thesis, an extension of these works in a wind farm by relaxation of the hypothesis of stationarity the wind speed and the power production, supposing that the latter are seasonal. Under this hypothesis the quality of the annual forecast improves considerably. We also suggest planning the wind power production during four seasons of the year. The use of the fractal model, allows us to find a "natural" division of the series of the wind speed to refine the estimation of the wind production by detecting abrupt change points. Statistical tools of the change points detection and the estimation of fractal models are presented in the last two chapters
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Zimba, Machilu. „Design houses in the Cape Town clothing value chain of production“. Master's thesis, University of Cape Town, 2008. http://hdl.handle.net/11427/8115.
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Includes abstract.Includes bibliographical references (leaves 79-81).
This exploratory study aimed to investigate the role that design houses play in the Cape Town clothing value chain of production. Semi-structured interviews were conducted with key informants, buyers in clothing retail companies, heads of design rooms in design houses, and homeworkers. Findings reveal that design houses act as intermediaries between retailers and clothing manufacturers or between retailers and homeworkers. In their latter role design houses are forging links between the informal and formal clothing economy. As in buyer-driven chains of production, retailers in the clothing value chain wield a substantial amount of power in determining prices. It was found that design houses are not completely powerless in their relationship with retailers, in fact, they posses knowledge that enables them to bargain over prices. The relationship between design houses and homeworkers was found to be an oppressive one, with homeworkers possessing little to no bargaining power. The increase in the number of design houses in Cape Town has assisted in the survival of the industry in the face of a number of difficulties. The continued presence of design houses creates the potential for development in the industry.
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Bjurek, Hans. „Essays on efficiency and productivity change with applications to public service production“. Göteborg : Nationalekonomiska institutionen, Handelshögsk, 1994. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=006407795&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Hicks, Natalie Ruth. „Impact of environmental change on primary production in model marine coastal ecosystems“. Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/3143.
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Coastal ecosystems, including estuaries, provide a range of services to humans, mediated by the species within these ecosystems. Microphytobenthos (MPB) play a vital role in many key processes within estuarine ecosystems, and provide a food source for higher trophic levels. Anthropogenic activity is already causing changes to ecosystems, through pollution, overexploitation and, more recently, climate change. Increasing temperature and carbon dioxide levels, and altered biodiversity, are likely to affect species, and their interactions, within these ecosystems. Much ecological research has focused on the effects of a single stressor on specific species or ecosystems, with relatively little work examining the effects of multiple stressors. The research in this thesis investigates the effects of altered environmental variables (light, tidal regime, temperature and carbon dioxide) and different macrofaunal diversity on primary production (MPB biomass) through a series of manipulative lab- based mesocosm experiments. This work also examines the temporal variability of environmental stressors on species across two trophic levels. Results demonstrate how multiple environmental stressors interact in a complex and non-additive way to determine an ecosystem response (MPB biomass, nutrient concentration), and the effects of altered biodiversity were underpinned by strong species effects. Temporal variation of stressors had a strong effect on ecosystem response. In marine coastal ecosystems, environmental changes through ocean acidification will have economic and social repercussions, directly impacting the human services and livelihoods that these systems provide. As such, future research should be focused on identifying and mitigating the inevitable multiple effects that future global change may have on coastal ecosystems.
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Dover, Caroline Jane. „British documentary television production : tradition, change and 'crisis' within a practitioner community“. Thesis, Goldsmiths College (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395608.
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This thesis will examine the professional identity, beliefs and practices of documentary programme-makers working in British television in the late 1990s. The principal purpose of this enquiry is to understand the ways in which traditions of genre and profession are influential within current documentary programme-making and how these traditions interact with structural and ideological changes within the British broadcasting industry. Original research findings presented here describe and analyse: changes in the types of documentary programmes broadcast during the 1990s; transformations in the production process; public debates about documentary television that took place in 1998/1 999; practitioners' production experiences and their perceptions of profession and genre. It is argued that documentary directors/producers comprise a symbolic community that is conceptually constructed through common practices, shared guidelines and traditions. Although documentarists' claims for documentary-making are sometimes contradicted by the practical realities of their work, the community and its associated traditions are particularly important to practitioners when industry change prompts fears of a "crisis" in their profession. The general theoretical aim is to describe and analyse relational and discursive aspects of both professional identity and cultural production within the context of a changing industry. Contained within the thesis is an exploration of the academic fields within which this study is sited, a discussion of the theoretical and methodological approach adopted and presentation of the findings arising from the programme survey (including a comparative study of documentary television in the United States) and the ethnographic-type research conducted with documentary television practitioners.
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Setter, Cassandra Marie. „Weed Control Effects on Native Species, Soil Seedbank Change, and Biofuel Production“. Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/29318.
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Aphthona spp. flea beetles were released in the Little Missouri National Grasslands
(LMNG) in western North Dakota in 1999 to control leafy spurge (Euphorbia esula L.). The
changes in soil seed bank composition and leafy spurge density were evaluated on two
ecological sites five (2004) and ten years (2009) after Aphthona spp. release to monitor
the effectiveness of the insects on weed control and associated change in plant
communities. In 2009, leafy spurge stem density averaged 2 and 9 stems m-2 in the loamy
overflow and loamy sites, respectively, compared to 110 and 78 stems m-2, respectively, in
1999 and 7 and 10 stems m-2, respectively, in 2004. Leafy spurge constituted nearly 67%
of the loamy overflow seed bank in 1999 compared to 17% in 2004 and 2% in 2009. In the
loamy seedbank, the weed represented nearly 70% in 1999 compared to approximately
11% in 2004 and 15% in 2009. As leafy spurge was reduced, native species diversity and
seed count increased ten years following Aphthona spp. release. High-seral species
represented 17% of the loamy overflow seedbank in 2009, an increase from 5% in 1999.
However, Kentucky bluegrass, a non-target weedy species, increased over 250% in the
loamy overflow seedbank from 2004 to 2009. The reestablishment of native plant species
has often been slow in areas where leafy spurge was controlled using Aphthona spp. A
bioassay was completed to evaluate native grass establishment when grown in soil from
Aphthona spp. release and non-release sites throughout North Dakota. Native grass
production was not affected when grown in soil collected from established Aphthona spp. sites (1.5 g per pot) compared to soil without insects (1.6 g per pot). The cause of reduced
native grass production in sites with Aphthono spp. previously observed is unknown but
may have been due to a chemical inhibition caused by the insects within the soil that no
longer exists. The native warm-season switchgrass (Ponicum virgotum L.) may be an
alternative to corn for efficient biofuel production; however, control of cool-season grassy
weeds has been a problem in switchgrass production. Various herbicides were evaluated
for smooth bromegrass (Bromus inermis Leyss.) and quackgrass [Elymus repens (L.) Gould]
control in an established switchgrass stand near Streeter, ND and a weed-infested field in
Fargo, ND. Switchgrass yield was higher than the control 14 mo after treatment (MAT)
when aminocyclopyrachlor or sulfometuron were applied early in the growing season, but
no treatment provided satisfactory long-term grassy weed control. Herbicides were
reevaluated at increased rates for smooth bromegrass or quackgrass control in Fargo.
Sulfometuron provided 99% smooth bromegrass control when applied at 280 g ha-1 in the
fall but injured other grass and forb species as well. Sulfometuron would likely be
injurious to switchgrass and could not be used for biofuel production.
Aminocyclopyrachlor did not injure other grass species but only reduced smooth
bromegrass control by 76% when applied at 280 g ha-1 in the fall. No treatment provided
satisfactory long-term quackgrass control.
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Zamora, Lauren Maria. „Inputs and Biogeochemical Impacts of Nutrient Deposition on the Subtropical North Atlantic“. Scholarly Repository, 2010. http://scholarlyrepository.miami.edu/oa_dissertations/477.
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Atmospheric nitrogen deposition to the ocean has more than doubled in the past 150 years due to anthropogenic activity, reaching levels comparable with nitrogen fixation in the subtropical North Atlantic. Previous studies have suggested that atmospherically deposited N may increase export production, decrease surface water phosphate levels, and substantially impact geochemical estimates of nitrogen fixation. This dissertation reports on the magnitude and biogeochemical fate of soluble N and P deposition in the subtropical North Atlantic. Aerosol and wet deposition time-series samples were used to determine the fluxes, sources, and N:P ratios of atmospheric nutrient deposition. Based on the magnitudes of total soluble N and P deposition, atmospheric nutrients are estimated to supply ~10-50% of allochthonous N to the North Atlantic subtropical gyre. Samples gathered in Barbados, the Canary Islands, and Miami indicate that atmospheric N sources are primarily anthropogenic (and thus, increasing) and that P sources are primarily natural (and thus relatively steady). Because inorganic nutrient concentrations in surface waters are in the low nM range, increasing P stress in surface waters may occur as a result of increasing N deposition. This assessment is supported by modeling studies, which also indicate that deposition would enhance surface P depletion. Inorganic N contributes nearly all (85-87%) of atmospherically deposited soluble N; the majority (~60%) of the remaining soluble organic N is comprised of an incompletely characterized pool of volatile basic organic N. Water soluble organic P contributes ~20-50% of soluble P. Because organic P contributes a relatively higher portion of soluble P as compared to organic N, the inclusion of organic matter in deposition estimates could both enhance the expected level of export production and reduce the predicted levels of P stress induced by atmospheric deposition. Further modeling studies indicate that the fate of atmospheric nutrients in the subtropical North Atlantic is controlled by non-Redfieldian processes, and that atmospheric nutrients eventually accumulate in the main thermocline. The research presented here suggests that future increases in atmospheric N emissions could have long-term impacts on surface ocean biology and nutrient cycles in the subtropical North Atlantic.
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Chu, Thi Thu Ha. „Mitigation of climate change: which technologies for Vietnam?“ Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-99232.
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Vietnam is one of the countries suffering from the most serious adverse effects due to climate change and sea level rise. The main cause of climate change is the increased activities generating greenhouse gases. Organic waste is the main source of carbon dioxide emission, which has the largest concentration among different kinds of greenhouse gases in the earth’s atmosphere. The conversion of organic waste and biomass into energy contributes not only to supply cleaner energy but also to reduce emissions of greenhouse gases. Vietnam has a large potential of biomass and agricultural by-products. The technologies to turn biomass into different kinds of bio-energies were developed and applied all over the world. Biogas was called as "brown revolution" in the field of new energy. Biogas production technology now has been studied and applied widely in the world, particularly in developing countries with warm climate that is suitable for anaerobic fermentation of organic waste. The biogas digester can be built with any capacity, needs small investment and the input materials are widely available. The biogas energy is used for many purposes such as cooking, lighting, running engines, etc. It is a production technology quite consistent with the economy of developing countries and really brings to life more civilized and convenient to rural areasViệt Nam là một trong những quốc gia bị tác động nghiêm trọng nhất do biến đổi khí hậu và nước biển dâng cao. Nguyên nhân chính của biến đổi khí hậu là các hoạt động gia tăng tạo ra các khí gây hiệu ứng nhà kính. Chất thải hữu cơ là nguồn chính phát thải khí carbon dioxide có nồng độ lớn nhất trong số các loại khí gây hiệu ứng nhà kính khác nhau trong bầu khí quyển của trái đất. Việc chuyển đổi chất thải hữu cơ và sinh khối thành năng lượng góp phần không chỉ cung cấp năng lượng sạch hơn mà còn giảm phát thải khí gây hiệu ứng nhà kính. Việt Nam có một tiềm năng lớn về sinh khối và phụ phẩm nông nghiệp. Các công nghệ biến sinh khối thành các loại năng lượng sinh học khác nhau đã được phát triển và áp dụng rộng rãi trên thế giới. Khí sinh học được gọi là "cuộc cách mạng màu nâu" trong lĩnh vực năng lượng mới. Công nghệ sản xuất khí sinh học đã được nghiên cứu và áp dụng rộng rãi trên thế giới, đặc biệt là ở các nước đang phát triển với nhiệt độ khí hậu nhiệt đới phù hợp cho quá trình lên men kỵ khí các chất thải hữu cơ để sản xuất khí sinh học. Bình phản ứng tạo khí sinh học có thể được xây dựng với công suất bất kỳ, nhu cầu đầu tư nhỏ, các nguyên liệu đầu vào sẵn có. Năng lượng khí sinh học đã được sử dụng cho nhiều mục đích như thắp sáng, nấu ăn, chạy động cơ, v.v... Đây là hoạt động sản xuất khá phù hợp với nền kinh tế của các nước đang phát triển và thực sự đem lại cuộc sống văn minh hơn và tiện lợi đến các khu vực nông thôn
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Holloway, Lewis E. „Global warming and changing patterns of horticultural production in the United Kingdom“. Thesis, Coventry University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282604.
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Blücher, Jakob, und Erik Wendin. „Change management i praktiken : En studie om förändringsprocesser på industriföretag“. Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-298443.
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Change management är ett område som fått allt större uppmärksamhet underde senaste decennierna. Det finns ännu inga exakta svar för hur en förändringbör genomföras då komplexa förhållanden omöjliggör ett definitivt svar. Istället måste varje organisation hitta sitt egna framgångsrecept. Under arbetet intervjuades ett antal personer med olika positioner från två olika industriföretag, Atlas Copco och Seco Tools, som de senaste fyra åren genomgått betydandeförändringsprocesser med positiva resultat. Kotter (2014); Lewin (1947) och Manktelow et al. (2016) har alla givit värdefullabidrag till forskningen inom Change management, och i arbetet finner vi att de två industriföretagen valt olika riktning under respektive förändringsprocess. Detta trots att målet med förändringarna varit detsamma och att båda företagenarbetat med Lean production under förändringsprocessen.
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Shand, Wayne Jon. „What are the institutional implications of co-production as a strategy for development?“ Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/what-are-the-institutional-implications-of-coproduction-as-a-strategy-for-development(d7bff04e-967f-445f-9d8d-096e76d7ffdc).html.
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This research investigates the institutional implications of co-production as a strategy for development. The study is located within international debates on global development targets beyond 2015 and how cities of the Global South meet the challenges of urbanisation and informality. With forecasts indicating the continuing growth of urban populations, there is an urgent need to consider how governments, working collaboratively with communities, meet the burgeoning demand for housing and basic services and create the institutions necessary for sustainable urban development. Co-production is examined empirically through an embedded case study with the Zimbabwe Homeless People’s Federation, its partner NGO Dialogue on Shelter Trust and the City of Harare Council. The research traces how co-productive relations have evolved between these stakeholders over the period 1997 to 2013. Co-production is considered as a mediating function that supports the creation of spaces for dialogue and problem-solving in complex urban environments. Drawing on sociological institutional theory, the thesis examines the implications of co-productive working on the discursive representation of people in poverty and the institutionalised practices of the state toward low income communities. The research finds that the organisational and deliberative processes associated with co-production are formative: contributing to the efficacy of low income communities and the state to address housing and basic service needs. The thesis reports firstly that community mobilisation has a significant role in bringing together the financial and human resources needed to contribute to co-production. More importantly mobilisation provides the social infrastructure needed to create agential communities. Secondly, where organised communities are involved in the governance of development projects, there is an enhanced capacity to problem solve, which galvanises state support for progressive policies. Thirdly, the research in Harare identified that processes and practices of co-production stimulate adaptation of institutional arrangements. These gain significance over time as they accumulate to affect discourse, epistemic practice and lead to small scale institutional change. The research confirms the potential significance of co-production for sustainable urban development. For communities, co-production serves to shift their subjectivity within existing institutional configurations; creating the potential to act outside of normatively defined roles. For the state, co-production creates an opportunity to establish spaces of deliberation that provide an infusion of resources and can bolster failing legitimacy. However, evidence from Harare also underlines that co-production is contextually defined and adaptive change is fragile in the face of stronger forces of politics and elite interests.
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Blumenkehl, Roberth, Fredrik Magnfält und Marcus Törnblom. „Strategic thinking of Swedish TV production companies : How do they cope with change?“ Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, ESOL (Entrepreneurship, Strategy, Organization, Leadership), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-15236.
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The Swedish TV production is facing great challenges today and actors on the market have to strategize to cope with these changes. This thesis explores what strategies are used, how they are formed, and what parameters are focused on when analyzing the market and industry, from a company perspective. Consequently, the purpose of this thesis is to investigate how Swedish TV production companies think strategically to cope with emerging market changes. The method used to collect data was semi-structured interviews. In order to retrieve ac-curate and reliable information we conducted four interviews. Three of these interviews were done with actors within the market. To ensure an accurate market picture, with high trustworthiness, we interviewed one large, one medium and one small company. Finally, we interviewed an independent market consultant, who provided an additional perspective. After having analyzed the material from each interview we later on com-pared the findings in a cross case analysis, in order to draw general conclusions. Our research and findings indicate that Swedish TV production companies mainly keep track of social trends, industry demand, the factors of the SWOT analysis, and the bar-gaining power of buyers in order to plan and form their strategies. Additionally, our findings indicate that Swedish TV production companies mainly use: a differentiation strategy and international strategic alliances. Moreover, we have also found that if Swe-dish TV production companies belong to an international conglomerate, they use this to their advantage.
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Juskan, Marten [Verfasser], Bernd [Akademischer Betreuer] Kortmann, Brigitte K. [Akademischer Betreuer] Halford und Peter [Akademischer Betreuer] Auer. „Production and perception of local variants in Liverpool English : : change, salience, exemplar priming“. Freiburg : Universität, 2016. http://d-nb.info/1139211234/34.
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Pham, Thanh Lan [Verfasser]. „Governance of Rice Production under Climate Change in Northern Vietnam / Thanh Lan Pham“. Aachen : Shaker, 2016. http://d-nb.info/1118259084/34.
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Le, Mare Ann. „Exploring the power to change : fair trade, development and handicraft production in Bangladesh“. Thesis, Durham University, 2007. http://etheses.dur.ac.uk/1891/.
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Altinalmazis, kondylis Andreas. „Tree diversity effects on root production, decomposition and nutrient cycling under global change“. Thesis, Bordeaux, 2021. http://www.theses.fr/2021BORD0067.
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L'hypothèse de l'assurance prévoit que les forêts composées de mélanges d'espèces d'arbres pourraient mieux résister aux conditions environnementales stressantes que les forêts composées d'une seule espèce d'arbre. La majorité des travaux antérieurs ont testé cette hypothèse en se focalisant sur la productivité et les variables de réponse associées sans prendre en compte les processus souterrains. L’objectif principal de ma thèse était d’étudier l’effet de la diversité des espèces d’arbres sur les processus souterrains impliqués dans la décomposition des racines à travers des gradients climatiques. J'ai émis l'hypothèse que le mélange d'espèces ayant des systèmes racinaires contrastés entraînerait une faible compétition souterraine, et se traduirait par la production de plus biomasse de racines fines. En outre, j'ai émis l'hypothèse que les racines ayant des caractéristiques chimiques et morphologiques contrastées dans les peuplements mixtes se décomposent plus rapidement. Dans des conditions de stress hydrique, j'ai émis l'hypothèse d'une décomposition plus lente mais d’une atténuation des mélanges d'arbres sur la décomposition en raison de l'amélioration des conditions micro-environnementales. Pour tester ces hypothèses, j'ai examiné la variation des caractéristiques fonctionnelles des racines et leurs conséquences sur les flux de C, N et P à l'échelle de l'écosystème à travers l’étude de : 1) la ségrégation verticale des racines et la biomasse des racines fines, 2) la dynamique des racines fines et les flux de nutriments associés et 3) la décomposition des racines fines et des feuilles mortes. Dans ce cadre, trois deux expériences de terrain ont été réalisé, l'une avec une expérience de plantation d'arbres de 10 ans avec du bouleau et du pin près de Bordeaux (expérience ORPHEE), la seconde le long d'un gradient latitudinal de forêts de hêtres matures dans les Alpes françaises (expérience BIOPROFOR).Les résultats obtenus montrent que les racines de bouleaux et de pins présentaient une distribution verticale similaire et une biomasse souterraine similaire de racines dans les mélanges d'arbres par rapport aux monocultures, contrairement à ma première hypothèse. Cependant, l'attribution plus importante du pin mais pas du bouleau à la croissance des racines dans les horizons du sol supérieur dans des conditions moins limitatives en eau suggère des conditions localement favorables qui peuvent conduire à une compétition asymétrique à la profondeur du sol. De plus, la production et la décomposition des racines fines étaient similaires dans les mélanges et dans les monocultures, en contradiction avec ma deuxième hypothèse. Il est intéressant de noter que les racines de bouleau, mais pas les racines de pin, ont libéré du P pendant leur décomposition, ce qui suggère un rôle important du bouleau dans le cycle du P et pour la nutrition en P des arbres sur ces sols sableux limités en P. Conformément à ma troisième hypothèse, j'ai observé une décomposition plus lente de la litière de feuilles et des racines fines en réponse à une sécheresse estivale prolongée, tout au long du gradient latitudinal dans les Alpes. Cependant, cette décomposition plus lente sous la sécheresse n'a pas été atténuée dans les peuplements forestiers à essences mixtes par rapport aux peuplements à essences uniques. Il est intéressant de noter qu’il y a une libération nette d'azote dans les racines fines en décomposition mais pas dans la litière de feuilles en décomposition, ce qui suggère un rôle distinct des racines fines dans le cycle de l'azote. En conclusion, j'ai constaté que le mélange des espèces d'arbres n'atténue pas les effets négatifs du changement climatique. Cette thèse démontre que la promotion de mélanges peut toujours être bénéfique pour au moins une des espèces d'arbres mélangées, par l'ajout d'espèces, car une espèce d'arbre peut en faciliter la nutrition minérale d’une autre par des flux souterrains de N et de PThe insurance hypothesis predicts that forests with tree species mixtures may resist better to stressful environmental conditions than forests composed of only one tree species. Most of the currently available literature tested this hypothesis for aboveground productivity and its related response variables, but less is known about belowground processes. In my PhD thesis, I studied the drivers of belowground productivity and decomposition across climatic gradients and how they are affected by tree mixtures. I hypothesized that mixing of tree species with contrasting rooting patterns and fine root morphologies, would result in a release of competitive pressure belowground, and translate into higher fine root standing biomass and increased fine root productivity. Moreover, I hypothesized that roots with contrasting chemical and morphological characteristics in mixed stands would decompose faster, which may be particularly important under nutrient-limited conditions. Under water-limiting conditions, such as during extreme summer drought, I hypothesized overall slower decomposition but an attenuating effect of tree mixtures on decomposition due to improved micro-environmental conditions, in particular for leaves, since roots decompose in a more buffered soil environment. To test these hypotheses I examined the variation in tree root functional traits (across- and within-species), and its consequences for fluxes of C, N and P at the ecosystem scale. I addressed three main objectives and associated research questions to quantify the interactive effect of tree mixtures and climate on: 1) vertical root segregation and fine root standing biomass, 2) fine root dynamics and their associated nutrient fluxes and 3) fine root- and leaf litter decomposition. I could benefit from two different field experiments for my work, one with a 10-year-old tree-plantation experiment with birch and pine close to Bordeaux (ORPHEE experiment), the second along a latitudinal gradient of mature beech forests in the French Alps (BIOPROFOR experiment).I observed that roots from the birch and pine tree-plantation showed similar vertical distribution and similar belowground root standing biomass in tree mixtures compared to monocultures, contrary to my first hypothesis. However, the greater allocation of pine but not of birch to root growth within the top soil horizons under less water-limiting conditions suggests locally favourable conditions that may lead to soil depth-specific asymmetric competition. In the same experiment, fine root production and decomposition were similar in mixtures and in monocultures, in contradiction with my second hypothesis. Moreover, I did not observe any interactive effects of tree mixtures with stand density or water availability. Interestingly though, birch roots, but not pine roots released P during root decomposition, which suggests an important role of birch in the P-cycle and for P nutrition of trees on these P-limited sandy soils. In line with my third hypothesis, I observed a slower decomposition of leaf litter and fine roots in response to reinforced and prolonged summer drought, irrespective of the position along the latitudinal gradient in the Alps. However, this slower decomposition under drought was not attenuated in forest stands with mixed tree species compared to single species stands. Compared to leaf litter, fine roots decomposed slower and released less C. Interestingly, I found a net N release in decomposing fine roots but not in decomposing leaf litter, which suggests a distinct role of fine roots in the N cycle. In conclusion, I found that mixing tree species did not attenuate negative effects of climate change. However, this thesis demonstrates that promoting mixtures can still be beneficial for at least one of the admixed tree species, through species addition (i.e., complementing one tree species with another tree species), as one tree species may facilitate another via belowground fluxes of N and P