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Linear and Non-linear Deformations of Stochastic ProcessesStrandell, Gustaf January 2003 (has links)
<p>This thesis consists of three papers on the following topics in functional analysis and probability theory: Riesz bases and frames, weakly stationary stochastic processes and analysis of set-valued stochastic processes. In the first paper we investigate Uniformly Bounded Linearly Stationary stochastic processes from the point of view of the theory of Riesz bases. By regarding these stochastic processes as generalized Riesz bases we are able to gain some new insight into there structure. Special attention is paid to regular UBLS processes as well as perturbations of weakly stationary processes. An infinite sequence of subspaces of a Hilbert space is called regular if it is decreasing and zero is the only element in its intersection. In the second paper we ask for conditions under which the regularity of a sequence of subspaces is preserved when the sequence undergoes a deformation by a linear and bounded operator. Linear, bounded and surjective operators are closely linked with frames and we also investigate when a frame is a regular sequence of vectors. A multiprocess is a stochastic process whose values are compact sets. As generalizations of the class of subharmonic processes and the class of subholomorphic processesas introduced by Thomas Ransford, in the third paper of this thesis we introduce the general notions of a gauge of processes and a multigauge of multiprocesses. Compositions of multiprocesses with multifunctions are discussed and the boundary crossing property, related to the intermediate-value property, is investigated for general multiprocesses. Time changes of multiprocesses are investigated in the environment of multigauges and we give a multiprocess version of the Dambis-Dubins-Schwarz Theorem.</p>
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Seismic fragility and retrofitting for a reinforced concrete flat-slab structureBai, Jong-Wha 30 September 2004 (has links)
The effectiveness of seismic retrofitting applied to enhance seismic performance was assessed for a five-story reinforced concrete (RC) flat-slab building structure in the central United States. In addition to this, an assessment of seismic fragility that relates the probability of exceeding a performance level to the earthquake intensity was conducted. The response of the structure was predicted using nonlinear static and dynamic analyses with synthetic ground motion records for the central U.S. region. In addition, two analytical approaches for nonlinear response analysis were compared. FEMA 356 (ASCE 2000) criteria were used to evaluate the seismic performance of the case study building. Two approaches of FEMA 356 were used for seismic evaluation: global-level and member-level using three performance levels (Immediate Occupancy, Life Safety and Collapse Prevention). In addition to these limit states, punching shear drift limits were also considered to establish an upper bound drift capacity limit for collapse prevention. Based on the seismic evaluation results, three possible retrofit techniques were applied to improve the seismic performance of the structure, including addition of shear walls, addition of RC column jackets, and confinement of the column plastic hinge zones using externally bonded steel plates. Finally, fragility relationships were developed for the existing and retrofitted structure using several performance levels. Fragility curves for the retrofitted structure were compared with those for the unretrofitted structure. For various performance levels to assess the fragility curves, FEMA global drift limits were compared with the drift limits based on the FEMA member-level criteria. In addition to this, performance levels which were based on additional quantitative limits were also considered and compared with FEMA drift limits.
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Säljande samspel : en sociologisk studie av privat servicearbeteAbiala, Kristina January 2000 (has links)
Interaction between people can be seen as a distinctive feature of 'post-industrial society'. In this study I investigate some of the conditions for this encounter in private service work in Sweden. I start by discussing some important concepts: service, service encounter and emotional labour. Three parties in an interactional triangle can be perceived: the service enterprise, the service worker and the customer. The service encounter is embedded in organisational frames. Recruiting for social competence and training for selling interaction are two facets of these frames. In interactive service work, control is complicated by the fact that a third party, the customer, is involved and that the borders between worker, work process and result are somewhat indistinct. Indirect forms of control can be used to affect workers' attitudes and thinking, as well as behaviour. Service work can be described as a form of acting. Different service workers will identify differently with their work role. In my study I observe both positive and negative experiences of work. A majority report that they sometimes are so tired of people that they want to be alone after work. I distinguish two dimensions of interactive service work: type of interaction and sales situation. Interaction can be more or less important, and the sales situation can be more or less concealed. Based on these dimensions I suggest a typology to illustrate some differences between different service occupations. Four types are suggested: (1) Work first, and customer later; (2) Personalised services; (3) Routine selling; and (4) Persuasive selling. In the second group we find the experts of interaction, but also the strongest signs of social strain.
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Development of a comprehensive annotation and curation framework for analysis of Glossina Morsitans Morsitans expresses sequence tagsWamalwa, Mark. January 2011 (has links)
This study has successfully identified transcripts differentially expressed in the salivary gland and midgut and provides candidate genes that are critical to response to parasite invasion. Furthermore, an open-source Glossina resource (G-ESTMAP) was developed that provides interactive features and browsing of functional genomics data for researchers working in the field of Trypanosomiasis on the African continent.
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Linear and Non-linear Deformations of Stochastic ProcessesStrandell, Gustaf January 2003 (has links)
This thesis consists of three papers on the following topics in functional analysis and probability theory: Riesz bases and frames, weakly stationary stochastic processes and analysis of set-valued stochastic processes. In the first paper we investigate Uniformly Bounded Linearly Stationary stochastic processes from the point of view of the theory of Riesz bases. By regarding these stochastic processes as generalized Riesz bases we are able to gain some new insight into there structure. Special attention is paid to regular UBLS processes as well as perturbations of weakly stationary processes. An infinite sequence of subspaces of a Hilbert space is called regular if it is decreasing and zero is the only element in its intersection. In the second paper we ask for conditions under which the regularity of a sequence of subspaces is preserved when the sequence undergoes a deformation by a linear and bounded operator. Linear, bounded and surjective operators are closely linked with frames and we also investigate when a frame is a regular sequence of vectors. A multiprocess is a stochastic process whose values are compact sets. As generalizations of the class of subharmonic processes and the class of subholomorphic processesas introduced by Thomas Ransford, in the third paper of this thesis we introduce the general notions of a gauge of processes and a multigauge of multiprocesses. Compositions of multiprocesses with multifunctions are discussed and the boundary crossing property, related to the intermediate-value property, is investigated for general multiprocesses. Time changes of multiprocesses are investigated in the environment of multigauges and we give a multiprocess version of the Dambis-Dubins-Schwarz Theorem.
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IVIK elevers skolintroduktion : Studie-och yrkesvägledares roll i skolintroduktionen för nyanlända invandrarungdomar i gymnasieåldern.Bernedal, Emili, Lehikoinen, Paula January 2007 (has links)
Syftet med uppsatsen var att undersöka studie- och yrkesvägledarens roll i skolintroduktionen för nyanlända invandrarungdomar i gymnasieåldern. Studie- och yrkesvägledare har intervjuats i fem kommuner i Stockholms län. Utifrån ett kvalitativt tillvägagångssätt vill vi undersöka studie- och yrkesväledarens roll i skolverksamheten och dess ramar. Resultatet visar att studie- yrkesvägledarna upplevde att samverkan och tidsaspekten var begränsande faktorer i introduktionsarbetet. Det framkom även hur de yttre och inre ramar påverkar kommuner och skolverksamheter, vilka ses som hinder. Uppsatsen tydliggör vikten av att en nationell strategi för skolintroduktion för nyanlända invandrarungdomar behövs. The purpose of this study is to elucidate the role of guidance counsellor for newly arrived immigrants of 16 - 20 years of age. The study has been taking place in five municipalities in Stockholm County, where counsellors have been interviewed. A qualitative attempt has been used to illuminate the counsellors role in school activity and there frames. The result shows that the counsellors experienced co- operation and time aspect as limitation factors in the work with school introduction. The result also told that the internal and external frames influence the local goverment and school activity in a limitation form. The study expresses the impotance of a national strategy for school introduction of newly arrived immigrants.
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A Comparative Study On Direct Analysis Method And Effective Length Method In One-story Semi-rigid FramesDemirtas, Afsin Emrah 01 September 2012 (has links) (PDF)
For steel structures, stability is a very important concept since many steel structures are governed by stability limit states. Therefore, stability of a structure should be assessed carefully considering all parameters that affect the stability of the structure. The most important of these parameters can be listed as geometric imperfections, member inelasticity and connection rigidity. Geometric imperfections and member inelasticity are taken into account with the stability method used in the design. At this point, the stability methods gain importance. The Direct Analysis Method, the default stability method in 2010 AISC Specification, is a new, more transparent and more straightforward method, which captures the real structure behavior better than Effective Length Method. In this thesis, a study has been conducted on the semi-rigid
steel frames to compare Direct Analysis Method and Effective Length Method and to investigate the effect of flexible connections to stability. Four frames are designed for different connection rigidities with stability methods existing in the 2010 AISC Specification: Direct Analysis Method and Effective Length Method. At the end,conclusions are drawn about the comparison of these two stability methods and the effect of semi-rigid connections to stability.
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Framing the water and sanitation challenge : A history of urban water supply and sanitation in Ghana 1909 - 2005Bohman, Anna January 2010 (has links)
This thesis analyses the development of urban water supply and sanitation services in Ghana from 1909 to 2005. Special focus is put on institutional arrangements with regard to networked, large scale and centrally managed water and sewerage services. The national and international historical context is highlighted as a way to understand policy redirections in the sector. Further on, the concept of frames is used as an analytical tool in order to put light on the assumptions, arguments and reasons behind institutional reforms. The thesis finds that it was not until the water and sanitation challenge was framed from a productivity perspective, as opposed to a pure humanitarian “health frame”, that funds were released for investments in WSS infrastructure. To begin with, development strategies were largely focussed on “filling the gaps” in terms of manpower, technical and financial resources. As the water challenge was increasingly framed as a matter of managing scarcity, a new thinking gradually emerged which emphasized entrepreneurship, business mindedness and management skills as a way to achieve more efficiency within the sector. This development was also paralleled by a shift in the favoured organisational structure from an extremely centralised state utility model to a gradual focus on decentralisation and unbundling of the sector. Here a strong focus was put on private sector participation in urban water supply whereas the non-commercially viable task of sewerage development was decentralised to local authorities. The study finds that formal institutional change in the sector has been largely donor driven. However, the privatisation element of the recent urban water sector reform did not go unquestioned and a strong opposition movement concerned with the possible negative effects of privatisation was formed. Eventually the initial lease arrangement was transformed into a management contract where its signing was brought to closure in 2005. Besides changing frames strong elements of continuity in the urban water supply and sanitation sector development in Ghana are identified. Historical evidence demonstrate that urban water delivery was a highly political issue in Ghana already during colonial times which, just as today, was closely connected to the framing of water as independence and national integrity. The issue of finance and pricing has remained a constant concern and so the debate cannot be categorized as a novel issue that solely emanates from neo-liberal political trends during the 1980’s and 1990’s. The thesis argues that a legacy of a colonial frame tends to continue normalising inequalities in access and consumption. Continuity can also be found in a neglect of the issue of sanitation which persistently lags behind the development of water distribution. The dissertation concludes that the perceived space for policy alternatives in Ghanaian WSS sector development has been largely constrained by the historical context and contemporary development theories. Therefore, to constantly strive towards a frame reflective policy dialogue is strongly encouraged as a way for policy planners and decision makers to make well informed decisions for the future.
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A Parametric Study On The Influence Of Semi-rigid Connection Nonlinearity On Steel Special Moment FramesMetin, Tolga 01 February 2013 (has links) (PDF)
In practice, steel frames are analyzed and designed by assuming all beam to column
connections as either rigid or simple. In real life, there are no such idealizations as rigid or simple and
all connections would actually belong to a group of connections named as semi rigid connections.
Various difficulties exist in modeling an accurate non-linear behavior of a steel structure,
where one of these challenges is the modeling of semi-rigid behavior of connections. A detailed finite
element model would take into account the complex interaction between all surfaces due to contact,
friction and bolt pretension besides the material and geometrical nonlinearity effects. All these
nonlinearity effects could be simply lumped as a moment-rotation type model at the connection
region. Such a methodology is followed in this thesis and the main aim is to study the lumped
nonlinear behavior of steel semi-rigid connections on the overall structural responses of steel Special
Moment Frames.
In this thesis three, nine and fifteen story steel Special Moment Frames are analyzed and
designed as rigid frames first, and then the frames are reanalyzed considering non-linear effects due to
semi-rigid connections. Changes in the ductility and overstrength reduction factors obtained from
pushover curves are compared between the rigid and semi rigid modeling alternatives.
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Cognitive dissonance, mental frames and the financial value of agricultural co-operativesLamprinakis, Lampros 05 June 2008
<p>The co-operative as an economic and social institution has long been recognized for its contribution to economic development as well as its positive effect on local communities. However, over the last decade or so substantial structural changes in the agricultural sector have undermined some of the most prominent North American co-operatives. In some cases, co-ops asked for bankruptcy protection, others ceased operations while some were transformed to for-profit firms. The present study offers three essays that explore the challenges that co-operatives are facing in terms of their relationship with their members in local markets, the decision-making process of their leaders and the co-ops' role in the modern economy.</p>
<p>These first two essays are linked by the fact that they both develop models that are about cognitions. Examining cognition offers some new insights to understanding the process behind the decline of agricultural co-ops. In the first essay the model examines consumers' cognitions, while the model in the second essay examines management's cognitions. The essays differ on the agent's ability to change the perceptions that result from those cognitions. Essay One assumes that consumers' perceptions are partially flexible and thus can change over time with some cost; on the other hand, essay Two assumes that beliefs are inflexible due to the high cost of changing them.</p>
<p>Essay One examines the relationship between a co-operative and its membership in a local market using an economic psychological approach. More specifically, the essay presents a modified rational-choice model to investigate how cognitive dissonance can influence members' loyalty. The effect of cognitive dissonance is analyzed in a case where a local co-operative operates alongside with an investor-owned firm (IOF) in a market. The model illustrates how cognitive dissonance can give rise to switching costs for those consumers who wish to switch to the IOF. Analytical results demonstrate the effect of these switching costs on equilibrium market shares and discuss how a drop in the dissonance cost because of managerial decisions by the co-op can result in dramatic drops in its market share.</p>
<p>Essay Two illustrates how management's mental frame can be incorporated into an economic model and develops a theoretical underpinning for the link between a strong mental frame and the financial difficulties that a firm might experience. The case of the Saskatchewan Wheat Pool with its Project Horizon plan is proposed as an example of a situation where the established mental frame gave rise to a belief regarding future member support that had a significant influence on the decision-making process of the co-op's CEO. The analysis includes a game theoretic model of a duopoly between a co-operative and an IOF, where mental framing is explicitly incorporated into the primitives of the model. Analytical results illustrate how the CEO's belief regarding member commitment can influence decision-making and therefore affect the market share and profits of the firm.</p>
<p>Essay Three uses non-parametric econometric techniques to examine the stock price effect of a co-op's acquisition by a publicly-traded IOF. The potential for this study emerged as a result of the takeover of Dairyworld, a dairy co-op, by Saputo, a publicly-traded private corporation. The study uses the prediction-error approach to estimate Saputo's returns after the acquisition as a deviation from its expected returns. A non-parametric bootstrap technique simulates Saputo's stock returns and examines its behavior around the acquisition date. The empirical results are consistent with a number of hypotheses, including the pro-competitive role that co-operatives are believed to have in the economy. The essay also includes a comprehensive discussion regarding the greater financial value that co-ops have for IOFs.</p>
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