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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Value of a privileged background

Watts, Michael James January 2013 (has links)
This thesis considers how informational imperfections may give rise to advantages for those born to relatively rich parents. The first chapter focuses on the separation of some societies into different classes. Within the model, classes provide greater advantages to those from privileged backgrounds and, even in the absence of legal barriers preventing the lower classes from accessing skilled jobs, the skilled amongst them are still de facto denied access to high paying jobs through statistical discrimination. This chapter shows that there can be a net benefit from class discrimination, versus a classless state, when it creates information relating to the abilities of the upper class. This theme is expanded on in chapter two where a signalling model more explicitly describes the statistical discrimination suffered by some members of society. The advantage conferred on those from privileged backgrounds generates income dispersion, which in turn reinforces the advantages of the rich. If this feedback is strong enough, the model may exhibit multiplicity of steady states. This multiplicity of steady states is backward looking: the income dispersion today depends on the extent to which firms use the information available to them, which in turn depends on the income dispersion in the previous generation. The model of chapter two also demonstrates why societies with more "meritocratic" institutions may exhibit less intergenerational income mobility: the income dispersion that meritocracy creates increases the value of a privileged upbringing. The final chapter adds parental investment to the model. In doing so it brings the model more squarely in line with the statistical discrimination literature, although the model does not exhibit a multiplicity of equilibria. There is a unique optimal investment rule for parents. Exogenous shocks to meritocracy are again examined. Meritocracy increases income variance and hence, from behind the veil of ignorance, creates greater uncertainty over the income an individual will receive. The model describes how a risk averse person might prefer to be born into an economy where they expect to be poorer but avoid this increased uncertainty, and so despite raising incomes, meritocracy may make agents, on average, more unhappy.
332

RELIABILITY ORIENTED TRANSPORT PROTOCOL IN WSN

Bejoy, B.J., Paramasivan, B. 01 June 2012 (has links)
Wireless Sensor Network consists of tens or thousands of sensor nodes scattered in a physical space and one or more Base stations or Sinks. Even thought developed for military applications now they find a wide variety of civilian applications also. Some of the applications are Target tracking, Animal monitoring, Vehicle monitoring. The need (or lack thereof) for reliability in a sensor network is firmly dependent upon the specific application the sensor network is used for. Some applications like re-tasking or reprogramming sensor nodes [upgrading software or algorithms, adding codes, scripts etc] over -the-air requires assured delivery of high-priority events to sinks. We believe that as the number of sensor network applications grows, there will be a need to build more powerful general-purpose hardware and software environments capable of reprogramming or retasking sensors to. / Wireless sensor network is a special form of wireless networks dedicated to surveillance and monitoring applications Reliability in wireless sensor network is application specific. The specific form of reliability might change from application to application. Our idea is to generate reliability based transport protocol that is customizable to meet the needs of emerging reliable data applications in sensor networks and is also adaptive when the nodes are mobile. In our approach, clusters are formed for minimizing energy dissipation. The nodes maintain a neighbor list to forward data and any changes in the local topology can trigger updates to a node’s neighbor list. If a node notices that its neighbor list has changed, it can spontaneously re-advertise all of its data thus providing reliable transport in mobility conditions also. Our approach has five phases-setup, relaying, relay initiated error recovery, selective status reporting and node supervising. Our simulation results prove that the proposed approach can outperform existing related techniques and is highly responsive to the various error and mobility conditions experienced in sensor networks.
333

The epitaxial layer design of HEMTs

Morton, Christopher Gordon January 1994 (has links)
No description available.
334

Empirical studies of earnings over the life cycle in Great Britain

Campbell, David Michael January 2001 (has links)
No description available.
335

The isolation and characterisation of Sry-related HMG box gene from Droposhila melanogaster

Sparkes, Andrew Charles January 1997 (has links)
No description available.
336

Gas emissions relevant to waste management, through watertables in porous media

Boltze, Uta January 1994 (has links)
No description available.
337

STRENGTH REQUIREMENTS AND ENERGY EFFICIENCY OF DIFFERENT STAIR-STEPPING STRATEGIES IN PERSONS WITH CHRONIC STROKE AND HEALTHY ADULTS

Ridgway, Heather 01 October 2013 (has links)
The majority of stroke survivors return to living in the community; however, muscle weakness and cardiovascular deconditioning can restrict mobility, limit community access and independence, particularly when challenging activities like stair negotiation are involved. A “step-by-step” (SBS) strategy (both feet per step) may be adopted in lieu of a “step-over-step” (SOS) method (one foot per step) to increase stability and off-load the paretic limb though the physical demands of the two methods are unknown. The main objective of this thesis was to investigate the strength and energy demands of the two stair-stepping strategies in chronic stroke compared to healthy adults. The first study identified the relative strength and aerobic demands of both strategies. The results showed that the stroke group produced similar peak joint moments compared to controls, despite their slower cadence suggesting that the stroke group exerts comparable ‘effort’ to move more slowly. The SBS method was associated with lower strength costs (relative to individuals’ maximum strength output) than SOS, however aerobic cost was significantly higher. The second study identified the mechanical energy expenditures (MEEs) and transfers related to both strategies. The MEEs were found to be lower when the SBS strategy was used. Though expenditures were similar between groups, the stroke group had higher expenditures associated with the work of the less affected knee extensors (lead limb) during ascent and descent and controls exhibited higher expenditures for the plantarflexors during ascent. The reduced output of the trail (affected) limb plantarflexors likely resulted in the increased workload of the knee extensors. Overall, the aerobic cost per step was higher in stroke, particularly during descent, suggesting that in addition to reducing cadence, persons with stroke may be co-contracting to increase stabilization during descent, thus increasing oxygen demands. This thesis provides novel information on the physical demands associated with two methods of stair negotiation demonstrating that the SBS strategy might be better suited to persons with chronic stroke by minimizing the strength demands on the paretic side, but the benefit comes at an elevated aerobic cost. This information is valuable to rehabilitation professionals engaged in retraining mobility to facilitate community reintegration. / Thesis (Master, Rehabilitation Science) -- Queen's University, 2013-09-30 13:42:08.209
338

Using experimental loads with finite element analysis for durability predictions

Dakin, John D. January 1995 (has links)
This research work involved the prediction of the fatigue life of an automotive rear suspension twistbeam assembly fitted to a vehicle travelling over a customer correlated durability route. This was achieved by making use of the integrated concepts of scaling and superposition of linear static finite element analysis being driven by experimental load data - the so called 'quasi-static time domain' approach. A study of the free body diagram of the twistbeam resulted in an indeterminate load set of some 24 components, with experimental data indicating that a state of static unbalance existed. Subsequent to developing a matrix-based generalised method ofload cell calibration to confum the foregoing, a modal technique was developed to partition the experimental data into a static load set, causing elastic deformations, and a rigid load set, imparting rigid body accelerations. The semi-independent characteristics of the twistbeam necessitated the coupling of large structural displacements with inertia relief. This required extensive modifications to the current techniques and led to the development and use of a three dimensional functional response matrix in place of the conventional two dimensional one. Recommendations concerning appropriate finite element boundary conditions were also formulated to handle these effects. Finally, the limitations of the uniaxial fatigue model were revealed under the application of a set of tools for analysing the biaxiality and mobility of the maximum absolute principal stress.
339

Biophysical studies to elucidate structure-activity relationships in β-defensins

De Cecco, Martin January 2011 (has links)
β-defensins are a class of mammalian defence peptides with therapeutic potential because of their ability to kill bacteria and attract host immune cells. In order to realise this potential, it is necessary to understand how the functions of these peptides are related to their structures. This thesis presents biophysical analysis of β- defensins and related peptides in conjunction with biological assays. These studies provide new insights into the structure-activity relationships of β-defensins. Ion mobility-mass spectrometry (IM-MS) is used throughout this thesis to probe the tertiary structure of peptides in vacuo and, by inference, make conclusions about their conformations in solution prior to ionisation. Where appropriate, IM-MS is complemented by other techniques, including high performance liquid chromatography and circular dichroism spectroscopy. First, the importance of a C-terminal cysteine residue within the murine β-defensin Defb14 is investigated. The functional and structural implications of chemically modifying the cysteine residue are examined. Second, the N-terminal region of Defb14 is modified by the substitution and deletion of amino acids. Again, the effects on biological activity and structure are discussed. Finally, the functional and structural overlap of β-defensins with another family of proteins – the chemokines – is considered. The oligomerisation of β-defensins and their interaction with glycosaminoglycans is of particular interest: structural data for human β-defensins 2 and 3 in the absence and presence of polysaccharides are presented.
340

Mobility Management : Ett nygammalt koncept med fokus på beteendeförändring

Gelinder, Martin January 2016 (has links)
Mobility Management (MM) eftersträvar ett helhetstänk där all samhällsplanering bedöms påverka trafikflöden och resmönstren. Områden som traditionellt inte tillhör trafikplanering anses inom konceptet Mobility Management vara medskapare i att nå effektiv mobilitet. Syftet med uppsatsen är att undersöka konceptets ursprung och dess innebörd, med tonvikt på de argument som åberopas för att få människor att ändra sitt resebeteende i hållbar riktning. Jag jämför även Mobility Management med tidigare planeringideal för att placera konceptet i ett sammanhang och finna ursprunget till idéerna. Genom att läsa dokument från nätverket Möjligheter med Mobility Management i Samhället (MMMiS), Trafikverket, SKL, Trivector och regeringen bildar jag en uppfattning om Mobility Managements innebörd i Sverige idag och sökte granska innehållet efter generella drag. Uppsatsen är därigenom en dokumentsanalys och en kvalitativstudie av Mobility Management. I uppsatsen finner jag att Mobility Management som koncept inte står ensamt mot sitt ursprung och innebörden är inte helt frånskild från tidigare trafikplanering. Skillnaden är dock att vi nu tydligare kan se att trafikplanering och övrig samhällsplanering hör samman.

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