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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.
361

Intressentdialogen i fokus : En studie om interaktionen mellan företag och ideella organisationer angående ansvar- och hållbarhetsfrågor

Brink, Erik, Knutsson, Ebba January 2015 (has links)
Studien ämnar undersöka hur intressentdialogen initieras och vad som sker mellan ett vinstdrivande företag och ideella organisationer, även kallade NGOs. Företag har idag en stor påverkan på samhället, där NGOs är en av företagens viktigaste intressenter. NGOs kan utöva påverkan på företag genom dialoger och företagen kan med framgång ta hjälp av NGOs i arbetet med ansvar- och hållbarhetsfrågor, även benämnt som CSR. Med utgångspunkt i teorin om intressenter och Triple Bottom Line visar studien, via tre olika intressentdialoger, hur dialogen initieras, vad syftet är samt vilka frågor som diskuteras. Vidare identifieras vilka frågor det råder konsensus och i vilka det kan uppstå konflikter. Genom en intervjustudie med representanter från sex organisationer, framkommer det att det råder till stor del konsensus. Det har sin förklaring i syftet med dialogen, den transparens som föreligger och en ökad medvetenhet hos företagen. De frågor där det uppkommer konflikter har bland annat berört finansiella kunskaper hos NGOs, riktning av donerade pengar och praktiskt arbete med projekt.
362

Understanding Transport Variability of the Antarctic Circumpolar Current Using Ocean Bottom Pressure

Makowski, Jessica 01 January 2013 (has links)
Previous studies have suggested that ocean bottom pressure (OBP) can be used to measure the transport variability of the Antarctic Circumpolar Current (ACC). The OBP observations from the Gravity Recovery and Climate Experiment (GRACE) are used to calculate transport along the choke point between Antarctica and Australia. Statistical analysis will be conducted to determine the uncertainty of the GRACE observations using a simulated data set. There has been some evidence to suggest that Southern Hemisphere winds and the Southern Annular Mode (SAM) or the Antarctic Oscillation (AAO) play a significant role in accelerating/decelerating ACC transport, along with some contribution from buoyancy forcing. We will examine whether average zonal wind stress, wind stress curl, local zonal winds, or the SAM are representative of the low frequency zonal mass transport variability. Preliminary studies suggest that seasonal variation in transport across the Australia-Antarctica choke point is driven by winds along and north of the northern front of the ACC, the Sub Tropical front (STF). It also appears that interannual variations in transport are related to wind variations centered south of the Sub Antarctic Front (SAF). We have observed a strong negative correlation/positive correlation across the STF of the ACC in the Indian Ocean, which suggests wind stress curl may also be responsible for transport variations.
363

Heat flow variability at the Costa Rica subduction zone as modeled by bottom-simulating reflector depths imaged in the CRISP 3D seismic survey

Cavanaugh, Shannon Lynn 09 November 2012 (has links)
3D seismic reflection data were acquired by the R/V Langseth and used to extract heat flow information using bottom-simulating reflector (BSR) depths across the southern Costa Rica convergent margin. These data are part of the CRISP Project, which will seismically image the Middle America subduction zone in 3D. The survey was conducted in an area approximately 55x11 km, northwest of the Osa Peninsula, Costa Rica. For the analysis presented here, seismic data were processed using a post-stack time migration. The BSR—a reverse polarity seismic reflection indicating the base of the gas hydrate phase boundary—is imaged clearly within the slope-cover sediments of the margin wedge. If pressure is taken into account, in deep water environments the BSR acts as a temperature gauge revealing subsurface temperatures across the margin. Two heat flow models were used in this analysis. In the Hornbach model BSR depth is predicted using a true 3D diffusive heat flow model combined with Integrated Ocean Drilling Program (IODP) thermal conductivity data and results are compared with actual BSR depth observations to constrain where heat flow anomalies exist. In the second model heat flow values are estimated using the heat flow equation. Uniform heat flow in the region should result in a deeper BSR downslope toward the trench due to higher pressure; however results indicate the BSR is deepest at over 325 meters below the seafloor (mbsf) further landward and shoals near the trench to less than 100 mbsf, suggesting elevated heat flow towards the toe of the accretionary prism. Heat flow values also reflect this relation. In addition to this survey-wide trend, local heat flow anomalies appear in the form of both circular patterns and linear trends extending across the survey, which can be related to mounds, thrust faults, folds, double BSRs, and seafloor erosion imaged in the seismic data. I suggest that these areas of higher local heat flow represent sites where advection of heat from deep, upward-migrating, thermogenically-sourced fluids and/or gases may be taking place. These heat flow trends have implications for not only earthquake nucleation, but also methane hydrate reserve stability. / text
364

Development of tandem mass spectrometric methods for proteome analysis utilizing photodissociation and ion/ion reactions

Shaw, Jared Bryan 13 September 2013 (has links)
The utility of 193 nm ultraviolet photodissociation (UVPD) and negative electron transfer dissociation (NETD) for the characterization of peptide anions was systematically evaluated. UVPD outperformed NETD in nearly all metrics; however, both methods provided complementary information to traditional collision induced dissociation (CID) of peptide cations in high throughput analyses. In order to enhance the performance of NETD, activated ion negative electron transfer dissociation (AI-NETD) methods were developed and characterized. The use of low-level infrared photoactivation or collisional activation during the NETD reaction period significantly improved peptide anion sequencing capabilities compared to NETD alone. Tyrosine deprotonation was shown to yield preferential electron detachment upon NETD or UVPD, resulting in N - C[alpha] bond cleavage N-terminal to the tyrosine residue. LC-MS/MS analysis of a tryptic digest of BSA demonstrated that these cleavages were regularly observed under high pH conditions. Transmission mode desorption electrospray ionization (TM-DESI) was coupled with 193 nm UVPD and CID for the rapid analysis and identification of protein digests. Comparative results are presented for TM-DESI-MS/CID and TM-DESI-MS/UVPD analyses of five proteolyzed model proteins. In some cases TM-DESI/UVPD outperformed TM-DESI-MS/CID due to the production of an extensive array of sequence ions and the ability to detect low m/z product ions. 193 nm UVPD was implemented in an Orbitrap mass spectrometer for characterization of intact proteins. Near-complete fragmentation of proteins up to 29 kDa was achieved. The high-energy activation afforded by UVPD exhibited far less precursor ion charge state dependence than conventional methods, and the viability of 193 nm UVPD for high throughput top-down proteomics analyses was demonstrated for the less 30 kDa protein from a fractionated yeast cell lysate. The use of helium instead of nitrogen as the C-trap and HCD cell bath gas and trapping ions in the HCD cell prior to high resolution mass analysis significantly reduced the signal decay rate for large protein ions. As a result, monoclonal IgG1 antibody was isotopically resolved and mass accurately determined. A new high mass record for which accurate mass and isotopic resolution has been achieved (148,706.3391 Da ± 3.1 ppm) was established. / text
365

Data assimilation for parameter estimation in coastal ocean hydrodynamics modeling

Mayo, Talea Lashea 25 February 2014 (has links)
Coastal ocean models are used for a vast array of applications. These applications include modeling tidal and coastal flows, waves, and extreme events, such as tsunamis and hurricane storm surges. Tidal and coastal flows are the primary application of this work as they play a critical role in many practical research areas such as contaminant transport, navigation through intracoastal waterways, development of coastal structures (e.g. bridges, docks, and breakwaters), commercial fishing, and planning and execution of military operations in marine environments, in addition to recreational aquatic activities. Coastal ocean models are used to determine tidal amplitudes, time intervals between low and high tide, and the extent of the ebb and flow of tidal waters, often at specific locations of interest. However, modeling tidal flows can be quite complex, as factors such as the configuration of the coastline, water depth, ocean floor topography, and hydrographic and meteorological impacts can have significant effects and must all be considered. Water levels and currents in the coastal ocean can be modeled by solv- ing the shallow water equations. The shallow water equations contain many parameters, and the accurate estimation of both tides and storm surge is dependent on the accuracy of their specification. Of particular importance are the parameters used to define the bottom stress in the domain of interest [50]. These parameters are often heterogeneous across the seabed of the domain. Their values cannot be measured directly and relevant data can be expensive and difficult to obtain. The parameter values must often be inferred and the estimates are often inaccurate, or contain a high degree of uncertainty [28]. In addition, as is the case with many numerical models, coastal ocean models have various other sources of uncertainty, including the approximate physics, numerical discretization, and uncertain boundary and initial conditions. Quantifying and reducing these uncertainties is critical to providing more reliable and robust storm surge predictions. It is also important to reduce the resulting error in the forecast of the model state as much as possible. The accuracy of coastal ocean models can be improved using data assimilation methods. In general, statistical data assimilation methods are used to estimate the state of a model given both the original model output and observed data. A major advantage of statistical data assimilation methods is that they can often be implemented non-intrusively, making them relatively straightforward to implement. They also provide estimates of the uncertainty in the predicted model state. Unfortunately, with the exception of the estimation of initial conditions, they do not contribute to the information contained in the model. The model error that results from uncertain parameters is reduced, but information about the parameters in particular remains unknown. Thus, the other commonly used approach to reducing model error is parameter estimation. Historically, model parameters such as the bottom stress terms have been estimated using variational methods. Variational methods formulate a cost functional that penalizes the difference between the modeled and observed state, and then minimize this functional over the unknown parameters. Though variational methods are an effective approach to solving inverse problems, they can be computationally intensive and difficult to code as they generally require the development of an adjoint model. They also are not formulated to estimate parameters in real time, e.g. as a hurricane approaches landfall. The goal of this research is to estimate parameters defining the bottom stress terms using statistical data assimilation methods. In this work, we use a novel approach to estimate the bottom stress terms in the shallow water equations, which we solve numerically using the Advanced Circulation (ADCIRC) model. In this model, a modified form of the 2-D shallow water equations is discretized in space by a continuous Galerkin finite element method, and in time by finite differencing. We use the Manning’s n formulation to represent the bottom stress terms in the model, and estimate various fields of Manning’s n coefficients by assimilating synthetic water elevation data using a square root Kalman filter. We estimate three types of fields defined on both an idealized inlet and a more realistic spatial domain. For the first field, a Manning’s n coefficient is given a constant value over the entire domain. For the second, we let the Manning’s n coefficient take two distinct values, letting one define the bottom stress in the deeper water of the domain and the other define the bottom stress in the shallower region. And finally, because bottom stress terms are generally spatially varying parameters, we consider the third field as a realization of a stochastic process. We represent a realization of the process using a Karhunen-Lo`ve expansion, and then seek to estimate the coefficients of the expansion. We perform several observation system simulation experiments, and find that we are able to accurately estimate the bottom stress terms in most of our test cases. Additionally, we are able to improve forecasts of the model state in every instance. The results of this study show that statistical data assimilation is a promising approach to parameter estimation. / text
366

From seafloor spreading to uplift: the structural and geochemical evolution of Macquarie Island on the Australian-Pacific plate boundary

Wertz, Karah Lynn 28 August 2008 (has links)
Not available / text
367

A comparison of two citizen initiatives in contrastingflood risk management systems,the Netherlands and Wales

Louwers, Petrus Rudolfus Cornelis January 2015 (has links)
This master thesis analyses two citizen initiatives; the flood action plan of LLanddowror, Wales and the mount plan of the Overdiepse Polder, the Netherlands. It uses the collaboration theory, the ladder of citizen participation, cross-scale interaction and community resilience to explain the role of citizens in flood risk management. The aim of this research is to see how governments facilitate citizens and if culture and context influence the roles of governments and citizens. The Welsh system is bottom-up with an increasing role for market and civil society to take responsibilities. Citizens generally insure themselves against flood damage. The Welsh system has enhanced community engagement and creating awareness is important. Dealing with big strategic issues seems to be difficult. The Dutch flood governance is more top-down which means less room for citizen initiatives. Citizens are not insured for flood damage since the government profiles itself responsible for floods therefore awareness amongst citizens is low. The Dutch system has benefits when dealing with large scaled projects but has issues with creating awareness as well as engaging citizens in water development. Assumingly there are opportunities for both countries to learn from each others’ way of dealing with flood risk management and citizen engagement.
368

Är GRI:s riktlinjer en förutsättning för en bra hållbarhetsredovisning?

Selmqvist, Annica, Andersen, Helena, Aronsson, Daniel January 2006 (has links)
Inledning: De senaste åren har det blivit allt viktigare för företagen att ta mer ansvar och att vara mer genomsynliga för alla intressenter. För att vara mer transparent kan företagen upprätta en speciell hållbarhetsredovisning som består av tre delar; miljö, socialt ansvar samt finansiell rapportering. De flesta av de stora och mest välkända företagen i Sverige har påbörjat någon form av hållbarhetsarbete. Det vanligaste ramverket med riktlinjer är i idag GRI (Global Reporting Initiative). Syfte: Syftet med den här uppsatsen är att undersöka om hållbarhetsredovisningar upprättade av företag som är anslutna till GRI är av bättre kvalitet än andra hållbarhetsredovisningar som är upprättade av företag som inte är anslutna till GRI, samt hur väl riktlinjerna följs av de anslutna företagen. Metod: I den här studien används en kvantitativ metod för att få en bred studie där generella samband kan hittas. Den data som används är sekundärdata i form av årsredovisningar och hållbarhetsredovisningar. Analysen sker med hjälp av beskrivande statistik, konfidensintervall samt Spearman’s rho. Resultat: Studien kom fram till att de företag som är anslutna till GRI generellt sett upprättar hållbarhetsredovisningar av bättre kvalitet än de företag som inte är anslutna till GRI. Det varierar dock kraftigt i vilken utsträckning de anslutna företagen följer GRI:s riktlinjer. Några av de anslutna företagen redovisar mycket bra men flera av de anslutna företagen redovisar väldigt dåligt. Studien av företagens hållbarhetsredovisningar delades in i tre olika delar. Det visade sig då att de GRI anslutna företagen inte redovisar bättre på alla delar, utan de ekonomiska rapporterna redovisades bättre av de företag som inte är anslutna till GRI. Det sociala och miljömässiga ansvaret redovisades bättre av de GRI anslutna företagen. Undersökningen visade också att det finns ett samband mellan dels företagens storlek och hållbarhetsredovisningens kvalitet och dels även antal sidor som hållbarhetsredovisningen omfattar gentemot hållbarhetsredovisningens kvalitet.
369

CSR i SMEs : – En förklaring av motiv och effekter

Edström, Alexandra, Persson, Anna January 2012 (has links)
Uppsatsens titel: CSR I SMEs – En förklaring av motiv och effekter Seminariedatum: 2012-05-31Kurs: 4FE03E Examensarbete för civilekonomprogrammet 30hp Författare: Alexandra Edström och Anna PerssonHandledare: Elin Funck Examinator: Lars-Göran Aidemark Nyckelord: CSR, Corporate Social Responsibility, samhällsansvar, intressenter,SMEs, Triple Bottom Line, motiv, effekter Bakgrund och problem: Teorierna kring CSR i SMEs är få och ofta motsägelsefulla. SMEs har dessutom en viktig påverkan på vårt samhälle, då de utgör den störstadelen av Sveriges näringsliv. CSR är ingen genväg till framgång utan effekterna kanbedömas först efter ett långsiktigt perspektiv, enligt Europakommissionen (2007)arbetar SMEs ofta med CSR utan att veta om det eller benämna det vid namn.Syfte: Syftet med detta examensarbete är att beskriva innebörden av CSR samtförklara motiven till och effekterna av CSR i SMEs. Metod: Vi har gjort en flerfallstudie på företagen Gnosjö Automatsvarvning AB,HangOn AB, Swede-Wheel AB och Sibes Metall AB. Vi har genomfört tvåsemistrukturerade intervjuer med två personer på respektive företag samt enfokuserad telefonintervju med respektive VD på varje företag. Examensarbetetbygger på abduktion som forskningsansats och av förklarande karaktär. Teoretisk referensram: Den teoretiska referensramen behandlar vedertagna teorierkring CSR, dess innebörd och historiska utveckling. Vi har kartlagt tidigare gjordastudier för att undersöka motiven till och effekterna av CSR i SMEs. Vidare har viredogjort för intressentteorin och legitimitetsteorin då dessa påverkar företags CSR. Resultat och slutsats: Vi har kunnat konstatera att CSR i SMEs gärna får varaomfattande och kostsamt så länge ansträngningarna gäller den lokala bygden.Det främsta motivet i SMEs utgörs av ledningens personliga värderingar och detmest framstående effekterna består av personlig stolthet och ökad ekonomisklönsamhet på sikt.
370

Mikrobiloginiai organinių medžiagų mineralizacijos ypatumai Vilniaus apylinkių ežerų dugno nuosėdose / Peculiarities of microbiological organic matter mineralization in bottom sediments of vilnius district lakes

Bagdevičiūtė, Daiva 25 November 2010 (has links)
2006 - 2007 metais atlikus tyrimus skirtingų sezonų metu buvo nustatyta, kad, antropogenizuotų Sudervės (Salotė, Gilužis, Gineitiškės) ir Riešės (Paežeriai, Raudondvaris, Riešė) upių baseinų ežerų vandenyje ir dugno nuosėdose susiformavo palankios aplinkos sąlygos SRB, heterotrofinių ir E. coli bakterijų augimui ir dauginimuisi. Skirtingais sezonais (pavasarį, vasarą, rudenį), tirtųjų ežerų dugno nuosėdose, SRB kiekis stipriai skirėsi ir svyravo nuo 0 iki 106 KSVS/ml. Sudervės upės baseino ežerų dugno nuosėdose, didžiausias šių bakterijų skaičius buvo nustatytas liepos mėnesį ir siekė 104 KSVS/ml. Tuo tarpu didžiausias SRB skaičius Riešės upės baseino ežerų dugno nuosėdose buvo nustatytas rugsėjo mėnesį ir siekė 106 KSVS/ml. Intensyviausiai heterotrofinės bakterijos tirtuose ežeruose vystėsi dugno nuosėdose, tuo tarpu vandens paviršiuje buvo aptkti vidutiniškai 1000 kartų mažesni šių bakterijų kiekiai. Daugiausiai heterotrofinių bakterijų vandens paviršiuje bei dugno nuosėdose, lyginant su kitais tirtaisiais ežerais, buvo aptikta Riešės ežere. Daugiausiai E. coli bakterijų Sudervės ir Riešės upių baseinų ežeruose buvo aptikta vandens paviršiuje liepos mėnesį, esant aukštai vandens temperatūrai (18,4 - 21,8 °C). Didžiausias šių bakterijų kiekis buvo užfiksuotas Gilužio ežere. Vienas pagrindinių veiksnių, skatinusių sulfatų redukcijos proceso intensyvumą tirtų ežerų dugno nuosėdose, buvo sulfatų kiekis. Daugiausiai šio junginio susikaupė vasarą. Todėl sulfatų redukcijos... [toliau žr. visą tekstą] / Investigations were carried out in water layers and bottom sediments of Suderve (Salote, Giluzis, Gineitiskes) and Riese (Paezeriai, Raudondvaris, Riese) rivers lakes, which undergo anthropogenic impact, in different seasons (spring, summer, autumn) of 2006-2007. It was established that the whole complex of abiotic factors formed favorable conditions for the growth of SRB, heterotrophic and E. coli bacteria. The differences in the abundance of sulphate reducing bacteria in bottom sediments did not reflect the intensity of the process. Generally, their amount varied from 0 to 106 colony forming units (CFU) per ml on media with lactate. The highest abundance of SRB in the lakes of Suderve river basin was recorded in July and reached 104 CFU per ml. Meanwhile, the highest abundance of SRB in the lakes of Riese river basin was recorded in September and reached 106 CFU per ml. The highest amount of heterotrophic bacteria was registered in bottom sediments while in water layer it was estimated 1000 times lower amount. In comparison with other investigated lakes the highest abundance of heterotrophic bacteria in water layer and bottom sediments was determined in Lake Riese. The highest amount of E. coli bacteria was determined in water layer by a high water temperature in July (18, 4 - 21, 8 °C) in basins of Suderve and Riese rivers lakes. The highest abundance of these bacteria was recorded in Giluzis Lake. The intensity of sulphate reducing process mainly depends on sulphate... [to full text]

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