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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.
101

Controlled Semi-Markov Processes With Partial Observation

Goswami, Anindya 03 1900 (has links) (PDF)
No description available.
102

Multiplatformní komunikace v přístupových sítích / Multiplatform communication in access networks

Novotný, Bohumil January 2017 (has links)
Doctoral thesis deals with failure detection methods in wireless access network using distributed stochastic algorithms. A new method of detecting a fault based on the push-sum algorithm has been designed and simulated. Within the scope of the work objectives, the statistical credibility of the average push-sum protocol convergence rate representative and the effect of message loss during the calculation on the robustness of the system using this protocol were compared. Based on the acquired knowledge, the ability of the protocol to mathematically derive deviations from the real average of the values in the specified topology was demonstrated and thereby the existence of an abnormality in the network has been proved or refuted.
103

Vliv stochastických selhávaní linek na protokol push-sum / Impact of stochastic link failures on push-sum protocol

Ecler, Tomáš January 2018 (has links)
This master’s thesis deals with the distributed computing and mathematical tools for modelling the distributed systems. Firstly, my attention is focused on a description of the distributed algorithms, characteristic failures for the distributed systems, and mathematical tools for an analysis of the distributed systems.The experimental part is concerned with the impact of stochastic link failures on the chosen parameters of the protocol Push-sum, namely the deviation of the final states from the average value, the convergence rate of the protocol, the distribution of the final states, and the distribution of the convergence rates. My intention is demonstrated using Matlab on a tree, a ring, a line, a star, and a fully-connected mesh topology. Was analyzed two functionalities of the protocol Push-sum, namely an estimation of the average value and an estimation of sum.
104

Game contingent claims

Eliasson, Daniel January 2012 (has links)
Abstract Game contingent claims (GCCs), as introduced by Kifer (2000), are a generalization of American contingent claims where the writer has the opportunity to terminate the contract, and must then pay the intrinsic option value plus a penalty. In complete markets, GCCs are priced using no-arbitrage arguments as the value of a zero-sum stochastic game of the type described in Dynkin (1969). In incomplete markets, the neutral pricing approach of Kallsen and Kühn (2004) can be used. In Part I of this thesis, we introduce GCCs and their pricing, and also cover some basics of mathematical finance. In Part II, we present a new algorithm for valuing game contingent claims. This algorithm generalises the least-squares Monte-Carlo method for pricing American options of Longstaff and Schwartz (2001). Convergence proofs are obtained, and the algorithm is tested against certain GCCs. A more efficient algorithm is derived from the first one using the computational complexity analysis technique of Chen and Shen (2003). The algorithms were found to give good results with reasonable time requirements. Reference implementations of both algorithms are available for download from the author’s Github page https://github.com/del/ Game-option-valuation-library
105

Investigating a Model Reversed-Phase Liquid Chromatography Stationary Phase with Vibrationally Resonant Sum Frequency Generation Spectroscopy

Quast, Arthur D. 13 June 2011 (has links) (PDF)
Reversed-phase liquid chromatography (RPLC) is a widely used technique for analytical separations but routinely requires empirical optimization. Gaining a better understanding of the molecular reasons for retention may mean more efficient separations with fewer trial and error runs to obtain optimized separations. Vibrationally resonant sum frequency generation (VR-SFG) is a surface specific technique that has allowed for in situ examination of model RPLC stationary phases under various solvent and pressure conditions. In order to improve on past work with model RPLC stationary phases two challenges had to be overcome. First, improved vibrational mode assignments of the C18 stationary phase were needed for proper understanding of this model system. Second, the synthesis of back-surface reference mirrors used in these VR-SFG experiments allowed us to better correct the relative intensities of the various spectral peaks present in typical spectra. After examination of model RPLC systems under various conditions, we have found that these model substrates have a significant amount of interference from nonresonant signal. This interference of resonant and nonresonant signals on fused silica surfaces has not been previously examined and further studies of the model RPLC stationary phase must properly deal with the non-negligible nonresonant interference that is present. We have seen changes in the VR-SFG spectra of these model systems under a variety of conditions including elevated pressure, however the changes are mostly due to nonresonant interference. These spectral changes, although apparently not solely from structural changes, need to be investigated further to better understand the molecular basis of retention in model RPLC systems.
106

Multikriterie-analys med hjälp av medborgardialog : En studie för lokalisering av havsbaserad vindkraftpark

Engström, Anton, Kallio, Marcus January 2022 (has links)
Rådande situation med klimatförändringar och oroligheter i Europa kräver åtgärder för att kunna skifta från fossila bränslen och energikällor till mer hållbara alternativ. Elförbrukningen väntas öka signifikant i Sverige och ett alternativ för att tillgodose hållbar energi och klimatmål är utvecklingen av vindkraft. Satsningar sker alltmer på havsbaserad vindkraft eftersom det är goda vindförhållanden och mindre påverkan för människor i närområdet eftersom vindkraftverken kan placeras långt från kusten. I många fall är det projekteringsföretag, kommuner och politiker som beslutar placeringen av vindkraftverken. Ett problem som uppstår är när allmänheten anser att det uppstår störningar på grund av att vindkraftverken placeras i dess närhet och att de inte får deltaga i planeringsprocessen. Studien syftar till att hitta lämpliga platser för havsbaserad vindkraft utifrån metoderna medborgardialog och multikriterie-analys för att kunna integrera medborgarinflytande i planeringsprocessen. ”Mjuka kriterier” som ofta tas upp i sammanhang om vindkraft har tagits i beaktning och har skickats ut i en enkätundersökning för att få in vad som är viktigast för invånare i Gävle kommun. Dessa innefattar hur stor påverkan respondenterna uppfattas kunna påverkas av som till exempel ljud, utsikt och buller. Utifrån dessa kriterier fick respondenterna rangordna samtliga för att skapa en viktning till multikriterie-analysen. Beskrivande statistik på vad respondenterna är oroliga för att påverkas av vid byggnation av havsbaserad vindkraft togs fram för att styrka studiens legitimitet. Resultatet visar att det är en stor majoritet av respondenter som är positivt inställd mot vindkraft och att respondenter inte uttrycker någon signifikant oro. Metoden MKA med viktning av rank sum weights användes för att skapa olika kartor faktor- och restriktionskartor baserat på respondenternas svar samt en teknisk analys utifrån en omfattande litteraturstudie. Den tekniska analysen använder kriterier som havsdjup, avstånd till kraftstationer och hamnar som inte klassas som ”mjuka kriterier”. Resultatet visar att medborgardialogen påverkar vilken lokalisering vindkraftverken får jämfört med den tekniska analysen. En slutgiltig karta skapades för att visa var någonstans vindkraftparken kan hamna om båda delarna tillgodoses. Studien tyder på att ett större underlag för medborgardialog kunnat ge ett tydligare resultat samt att viss typ av data hade krävts för en ordentlig teknisk analys. Det nya som denna studie har utvecklat är en metod för att föra en medborgardialog gällande havsbaserad vindkraft och kvantifierat invånarnas åsikter till geografiska data. / The current situation with climate change and unrest in Europe requires measures to be able to switch from fossil fuels and energy sources to more sustainable alternatives. Electricity consumption is expected to increase significantly in Sweden and an alternative for meeting sustainable energy and climate goals is the development of wind power. Investments are increasingly being made in offshore wind power because it has adequate wind conditions and less impact for people in the immediate area since the turbines can be located far from the shore. In many cases, it is corporations, municipalities and politicians who decide on the location of the wind turbines. A problem that arises is when the public considers that disturbances occur due to the fact that the wind turbines are located in their vicinity and that they are not offered the possibility to participate in the planning process. The study aims to find suitable places for offshore wind power based on the methods citizen dialogue and multi-criteria analysis to be able to integrate citizen influence in the planning process. "Soft criteria" that are often raised in the context of wind power was taken into account and was included in a survey to address what is important for residents of Gävle municipality. These include how much impact the respondent is perceived to be affected by, such as sound, view and noise. Based on these criteria, the respondents were allowed to rank all of them in order to create a weighting for the multi-criteria analysis. Descriptive statistics based on what the respondents are worried about being affected by during the construction of offshore wind power were produced to prove the legitimacy of the study. The results show that a large majority of respondents are positive towards wind power and that respondents do not express any significant concern regarding the construction of offshore wind power. The MCA method with weighting method rank sum weights was used to create different factor and constraint maps based on the survey answers and a technical analysis based on an extensive literature study. The technical analysis uses criteria such as bathymetry, distance to power stations and ports that are not classified as "soft criteria". The results show that the citizen dialogue affects the location of the wind turbines compared to the technical analysis. A final map was created to show where the wind farm could end up if both parts are met. The study indicates that a more comprehensive citizen dialogue could have given a more concise result and that a certain type of data had been required for a more thorough technical analysis. The new thing that this study has developed is a method for conducting a citizen dialogue regarding offshore wind power and quantifying the inhabitants' opinions to geographical data.
107

Uptake of short-chain alcohols by sulfuric acid solutions using raman and vibrational sum frequency spectroscopies, and atmospheric implications

Van Loon, Lisa Lauralene 27 March 2007 (has links)
No description available.
108

Vibrational Sum Frequency Generation Studies of Biological and Atmospheric Relevant Interfaces: Lipids, Organosulfur Species and Interfacial Water Structure

Chen, Xiangke 25 October 2010 (has links)
No description available.
109

A convergent reformulation of perturbative QCD

Alves, Ricardo Joao Gaio January 2000 (has links)
We present and explore a new formulation of perturbative QCD based not on the renormalised coupling but on the dimensional transmutation parameter of the theory and the property of asymptotic scaling. The approach yields a continued function, the iterated function being that involved in the solution of the two-loop β-function equation. In the so-called large-b limit the continued function reduces to a continued fraction and the successive approximants are diagonal Padé approximants. We investigate numerically the convergence of successive approximants using the leading-b approximation, motivated by renormalons, to model the all-orders result. We consider the Adler D-function of vacuum polarisation, the Polarised Bjorken and Gross-Llewellyn Smith sum rules, the (unpolarised) Bjorken sum rule, and the Minkowskian quantities R(_r) and the R-ratio of e(^+)e(^-) annihilation. In contrast to diagonal Fade approximants the truncated continued function method gives remarkably stable large-order approximants in cases where infra-red renormalon effects are important. We also use the new approach to determine the QCD fundamental parameters from the R(_r) and the R-ratio measurements, where we find Ā(^(3))(_MS)=516±48 MeV (which yields a(_s)(µ=m(_r))=0.360(^+0.021)(_=0.020)), and Ā(^(5))(_MS)=299(^+6)(_-7) MeV (which yields a(_s)(µ=m(_zo)=0.1218±0.0004), respectively. The evolution of the former value to the m(_zo) energy results in a(_s)(µ= m(_zo)) = 0.123 ± 0.002. These values are in line with other determinations available in the literature. We implement the Complete Renormalisation Group Improvement (CORGI) scheme throughout all the calculations. We report on how the mathematical concept of Stieltjes series can be used to assess the convergence of Padé approximants of perturbative series. We find that the combinations of UV renormalons which occur in perturbative QCD may or may not be Stieltjes series depending on the renormalisation scheme used.
110

The Dangers of Corporate Champions: The East India Company's Devastating Impact on Britain

Newman, Richard 01 January 2017 (has links)
This paper argues against the common historical belief that the British East India Company’s actions benefited the British Public. While many recent historical works argue that the Company had detrimental effects on India, the common consensus believes that the Company’s actions while pillaging India benefited Britain through economic treasures and access to luxuries. In the first section of the text, the author describes the British East India Company’s corruption, propaganda, and lobbying efforts to enrich individual members of the Company and protect personal and corporate profits. The next section describes the Company’s impact on Britain and argues that the Company was an overwhelmingly negative investment for the British taxpayer. The author compares the East India Company’s historic actions and impacts on Britain to the impact of modern big corporations on their own nations. The text concludes with an argument that the popular narrative, which holds that large corporations’ interests coincide with that of the nation’s public interest, is both inherently mistaken and fraught with danger. The author argues against a zero-sum worldview and for a corporate sector with checks and balances.

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