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Identificação bacteriana por derivação de ácidos graxos extraídos de células íntegras / Bacterial identification by fatty acid derivation extracted from whole cellsFábio Luiz Camacho Pacheco 16 June 2009 (has links)
As salas limpas são amplamente empregadas em indústrias farmacêuticas destinadas a fabricar medicamentos e dispositivos estéreis. Nós empregamos coloração de Gram e cromatografia gasosa de ésteres metílicos de ácidos graxos extraídos de células íntegras de microrganismos ambientais para caracterizar e identificar bactérias isoladas em 50 salas limpas diferentes projetadas para a fabricação de medicamentos estéreis e para fornecer um perfil de ácidos graxos das espécies mais comuns de bactérias isoladas. Uma análise estatística nos permitiu corroborar estudos anteriores e confirmar que cocos Gram positivos é o grupo mais relevante de microrganismos presentes nas salas limpas avaliadas. A espécie predominante é Micrococcus luteus, isolada de salas classe B e de pessoal, seguida de Staphylococcus cohnii em classe C, Bacillus subtilis em classe A e Staphylococcus hominis em classe D. Os perfis de ácidos graxos destas bactérias são, na maioria, consistentes com as bibliotecas padrão. Nós também tentamos estabelecer uma correlação entre a estação do ano e o nível de contaminação, embora a análise de variância tenha mostrado que não há diferença significativa entre o nível de contaminação no decorrer das estações. Além do mais, análises repetidas com um aumento gradual de massa celular nos permitiram concluir que a quantidade ótima de material celular necessário para extração de ácidos graxos varia com a espécie de bactéria. Finalmente, um estudo comparativo de algumas bactérias incubadas em diferentes temperaturas confirmou que o perfil de ácidos graxos é altamente influenciado pela temperatura. Portanto, nós acreditamos que este trabalho possa contribuir para identificar e compreender a comunidade bacteriana de algumas salas limpas farmacêuticas. / Clean rooms are largely employed in pharmaceutical companies whose purpose is to produce sterile drugs and devices. We employed Gram staining and gas chromatography of fatty acid methyl esters extracted from whole cells of environmental isolates to characterize and identify bacteria isolated in each of 50 different clean rooms designed for the manufacturing of sterile medicinal products and to provide a fatty acid profile of the most common species of isolated bacteria. Statistical analysis allowed us to corroborate previous studies and confirm that Gram-positive cocci are the most relevant group of microorganisms inside the studied clean rooms. The predominant species is Micrococcus luteus, isolated from Grade B zones and from personnel, followed by Staphylococcus cohnii in Grade C, Bacillus subtilis in Grade A and S. hominis in Grade D. Fatty acid profiles of these bacteria are, to a great extent, consistent with standard libraries. We also attempted to establish a correlation between season and level of contamination, although variance analysis showed that there is no significant difference on the level of contamination throughout seasons. Furthermore, repeated analysis with a gradual increase in cell mass allowed us to conclude that the optimal amount of cell material depends on the species of the bacteria studied. Finally, a comparative study with some bacteria incubated in different temperatures confirmed that fatty acid profile is highly influenced by temperature. Therefore, we believe that this work can contribute to identify and understand the bacterial community of some pharmaceutical clean rooms.
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Reaching the Pinnacle of Success: A Content Analysis using Organizational Culture Theory and Sport Hall of Fame OrganizationsHiestand, Katie 22 June 2022 (has links)
No description available.
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Förnybara drivmedel och deras förutsättningar för implementering i FörsvarsmaktenSöderberg, Klara January 2022 (has links)
Today’s society is adapting to reduce the climate footprint which is why the Swedish Armed Forces is expected to revise its use of fossil fuel. The choice of fuel is not obvious, and this report aims to examine the possibilities and limitations for a few renewable fuel’simplementation in the Swedish Armed Forces. Based on Moche Kress logistics concept an analyzing tool were created. The analyzing tool is based on the category’s economy, industry/engine technology, technology/characteristics, inventory, storage facilities and transports. Methods used is a mixture of document collection and interviews with an expert in the area of alternative fuels and combustion engines. The renewable fuels analyzed are FAME, HVO, biogas and DME. Results of the analysis show that FAME has a relative low cost for production, only requires small-scale modifications in engines, the domestic production is expected to expand and is interoperable with the current supply chain. The biggest limitations are the bad qualities regarding cold temperatures and can’t be stored longer periods of time. HVO has a bit higher production cost but has good qualities even in colder temperatures, high energy density, can beused in all diesel engines after an approval from the manufacturer and can be implemented incurrent infrastructure as well as supply chain. Raw materials consist on the other hand largely from palm oil production. Biogas has a relatively high production cost, low energy density, requires extensive renovations/installations of engines/fuel systems and can neither be implemented in current infrastructure nor supply chain. Positive features are its good qualities in cold temperatures and big part domestic production. DME also has good qualities in cold temperatures but requires a new injection system and a new tank, can’t be implemented in neither current infrastructure nor supply chain and is not produced anywhere globally today. Based on the results from the analysis HVO were concluded as the most realistic alternative for the Swedish Armed Forces. Further conclusions were that FAME is not the best alternative and neither biogas nor DME were estimated as a realistic choice today. The last conclusion of the analysis is that none of the alternatives had possible self-sufficiency in Sweden as of now. / Mot bakgrund av att samhället ställer om till att bli mer klimatpolitiskt hållbart förväntas ett drivmedelsbyte vara aktuellt för Försvarsmakten. Vilket drivmedel som är aktuellt för detta är inte självklart och detta arbete syftar till att undersöka vilka förutsättningar ett antal förnybara drivmedelsalternativ har för implementering i Försvarsmakten. Utifrån Moche Kress logistikkoncept togs ett analysverktyg fram som utgår från kategorierna ekonomi, industri/motorteknik, teknologi/egenskaper, lagerhållning/tillgänglighet, infrastruktur för lagerhållning och transporter. Empiri samlades därefter in via en dokumentinsamling samt intervjuer med en expert inom alternativa drivmedel och förbränningsmotorer. Alternativen som analyserats är FAME, HVO, biogas och DME. Resultat av analysen var att FAME har en relativt låg produktionskostnad, enbart kräver mindre anpassningar i motorer, har inhemsk produktion som förväntas expandera och kan implementeras i befintlig försörjningskedja. Största begränsningarna är att det har begränsade köldegenskaper samt låg lagringsbeständighet. HVO har en något högre produktionskostnad men goda köldegenskaper, högt energiinnehåll, kan nyttjas i samtliga dieselmotorer efter tillverkarens godkännande och kan implementeras i befintlig försörjningskedja respektive infrastruktur. Råvaror kommer dock till stor del från palmoljeproduktion. Biogas har en relativt hög produktionskostnad, lågt energiinnehåll, kräver omfattande renoveringar/installationer av motorer/bränslesystem och kan inte implementeras i varken befintlig försörjningskedja eller infrastruktur. Det har dock bra köldegenskaper och hög andel inhemsk produktion. DME har bra köldegenskaper, men kräver nytt insprutningssystem och ny tank, kan inte implementeras i dagens försörjningskedja eller infrastruktur och produceras ingenstans i världen idag. Utifrån analysens resultat bedömdes HVO som det mest realistiska alternativet för Försvarsmakten. Utöver det bedöms inte FAME som mindre fördelaktigt, och biogas respektive DME som orealistiska alternativ i dagsläget. Den sista slutsatsen av analysen var att inget alternativ medger självförsörjning i Sverige idag.
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Kvinnan, kändisen, konfliktkatalysatorn : Bilden av kändisen Anna Anka i svensk nyhetsjournalistikBlomstrand, Nicole, Andersson, Maria January 2010 (has links)
The aim of this thesis was to examine how newspaper journalism represented the celebrity Anna Anka. Which roles and qualities did the media ascribe Anna Anka and in what way did the media frame her as a woman. We examined texts and photographs from two Swedish newspapers, Aftonbladet and Dagens Nyheter, 16 texts were analysed. The method we used were discourse analysis with focus on relations, identities and representation. The result showed that Anna Anka was represented in an essentially equal way in both newspapers. The image of Anna Anka seems to be multifaceted. In the texts Anna Anka becomes a symbol for conflicts that emerge in discourses regarding gender, celebrity and Swedish values. As a woman she is both portrayed as controversial and appearance-fixated. As a wife she is traditional, a woman who takes care of house and family and lets her husband be the provider. On the other hand she is described as a woman who does not follow the traditional norm, she is independent and has a possibility to support herself. As a celebrity, Anna Anka is framed as fairly new in the public appearance. But in some texts the newspapers define her as a woman who does not deserve to be the celebrity she is. Anna Anka is well aware of how the celebrity culture works, what the media finds interesting. As a Swede Anna Anka is framed as a person who no longer quite belongs in Sweden, and therefore is allowed to criticize Sweden and the Swedish values.
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Autobiographical narratives : an investigation into the artist as celebrityNorval, Anet January 2014 (has links)
Submitted in partial fulfillment in compliance with the requirements for the Masters Degree in Technology: Fine Art, Department of Fine Art and Jewelery Design, Durban University of Technology. Durban. South Africa, 2014. / This dissertation introduces and explores the link between the phenomenon of the celebrity artist and autobiographical narratives. It investigates the possibility that artists plan, strategize and embellish or create stories that could gain enough attention from the general public to achieve celebrity status. This enquiry will establish various contexts, that of different artists, the audience, the celebrity artist and my own, locating the research and findings within a historical and contemporary discourse.
The research presents several concepts and factors that will contribute to the understanding and contextualization of the hypothesis, as well as possibly substantiate it. Concepts such as celebrity, fame, narcissism, the ego and exhibitionism form the basis of the enquiry while theories based on narrative, autobiography and memory rehearsal provide credible support and background. The nature of this dissertation requires a broad investigation including contemporary social sciences, philosophy and psychology, media studies and history of art.
In order to determine whether the aforementioned concepts and theories are employed by certain individuals to gain celebrity status, three celebrity artists are introduced through their biographies, rises to fame and their popularity and relationships with the general public. The artists, Andy Warhol, Jean-Michel Basquiat and Tracey Emin are introduced chronologically. All three artists have established public identities and in the attempt to substantiate whether these identities are constructed and pre-mediated the final analysis (in form of a causal analysis) presents fluctuating results with several possible causes.
As part of this enquiry I introduce my creative output through discussing my autobiography, themes (of my work), mediums (I choose to use), exhibition and the resonance found with the selected artists. In light of the discussions based on the backgrounds, public identities and resonance I have found with each artist I determine whether I embellish my stories to gain fame.
The research is conducted through qualitative research methodologies and presented in a consequential order. The methodological approach and process is best described through the term Bricolage, which refers to the use of multiple methodologies in its approach to research, in other words, a hybrid of praxis (Barrett & Bolt ed., 2010). The process of this enquiry includes theoretical research, historical research; studio based and –led research, as well as a causal analysis.
As part of the research, many factors have been considered and discussed, as an investigation into autobiography; the research will aid me in progressing as an artist as well as contribute to the greater knowledge of the autobiographical field. Furthermore, introducing and exploring the link between autobiographical narratives and the artist, as celebrity is a discourse that can be developed and further expanded on. Through this research I have attempted to establish a link between high art and popular culture, and the artist and the audience.
The findings represent a process of attempting to understand a complex set of possible causes with one ultimate effect and the influence it has on an individual and the general population. Many artists want to be famous and would go through the motions to become a celebrity. It does, however, fully depend on the individual and no ultimate formula can be presented. / M
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Vybrané problémy českých médií a novinářské profese na příkladu pronikání smyšlených událostí a recesistických obsahů do zpravodajství / Selected problems of the czech media and journalistic profession on the exemple of the intrusion of fictitious events and news satire into official newsSeidlová, Tereza January 2014 (has links)
This diploma thesis focuses on the problematic aspects of the journalistic profession nowadays, namely on the example of the penetration of the mystifying jokes to the mainstream media. In three specific cases where the authors of the mystifying pranks managed to penetrate the media, the work illustrates the most common mistakes journalists can make and focuses on trends, which stand for these tendencies. Part of this work is the analysis of the mystifying contents that appeared on jokes websites, on Facebook or in the context of interpersonal communication, and subsequent analysis of the media in which these mystifying reports appeared in the form of the real events. The interviews with both stakeholders - authors of the hoax contents and media representatives - will subsequently serve for the illustration of the overall issue and the final conclusion.
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Characteristics of Fame-Seeking Individuals Who Completed or Attempted Mass Murder in the United StatesWills, Angelica 01 January 2019 (has links)
Previous researchers have found mass murderers characterized as loners, victims of bullying, goths, and individuals who had a psychotic break. A gap in the literature that remained concerned the motive and mindset of mass murderers before their attack, particularly those who seek fame, and why they are motivated by such violent intentions. The purpose of this study was to provide a deeper analysis of the characteristics of fame-seeking individuals who have completed or attempted mass murder, as well as insight into their behavior on social media. The conceptual framework consisted of a constructivist model, which guided the exploration the purposeful sample of 12 Americans who completed or attempted mass murder. The research questions aligned with themes provided by Bandura's social learning theory, Sulloway's theory of birth order and family dynamics, Millon and Davis's psychopathy theories, O'Toole's findings on the copycat effect, and Lankford's criteria for fame-seeking mass murderers, and guided an analysis of open-source data. Six main themes among fame-seeking individuals in the United States who had completed or attempted mass murder emerged: (a) fame as primary motivation, (b) preoccupation with violence, (c) presence of specific role models/copycat behavior, (d) strong opinions about society/racial groups, (e) symptoms of narcissism/mood disorder/personality disorder, and (f) failed relationships. These findings add to the knowledge about mass murder and fame seeking. Social change may occur through recommended evaluation of and improvements in current mental health approaches, improved threat assessment, expanded education on characteristics of mass murderers, and dissemination of information related to mass murder.
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Optimisation of biodiesel production via different catalytic and process systemsBabajide, Omotola Oluwafunmilayo January 2011 (has links)
<p>The production of biodiesel (methyl esters) from vegetable oils represents analternative means of producing liquid fuels from biomass, and one which is growing rapidly in commercial importance and relevance due to increase in petroleum prices and the environmental advantages the process offers. Commercially, biodiesel is produced from vegetable oils, as well as from waste cooking oils and animal fats. These oils are typically composed of C14-C20 fatty acid triglycerides. In order to produce a fuel that is suitable for use in diesel engines, these triglycerides are usually converted into the respective mono alkyl esters by base-catalyzed transesterification with short chain alcohol, usually methanol. In the first part of this study, the transesterification reactions of three different vegetable oils / sunflower (SFO), soybean (SBO) and waste cooking oil (WCO) with methanol was studied using potassium hydroxide as catalyst in a conventional batch process. The production of biodiesel from waste cooking oil was also studied via continuous operation systems (employing the use of low frequency ultrasonic technology and the jet loop reactor). The characterisation of the feedstock used and the methyl ester products were determined by different analytical techniques such as gas chromatography (GC), high performance liquid chromatography (HPLC) and thin layer chromatography (TLC). The effects of different reaction parameters (catalyst amount, methanol to oil ratio, reaction temperature, reaction time) on methyl ester/FAME yield were studied and the optimum reaction conditions of the different process systems were determined. The optimum reaction conditions for production of methyl esters via the batch process with the fresh oil samples (SFO and SBO) were established as follows: a reaction time of 60 min at 60 º / C with a methanol: oil ratio of 6:1 and 1.0 KOH % wt/wt of oil / while the optimum reaction conditions for the used oil (WCO) was observed at a reaction time of 90 min at 60 º / C, methanol: oil ratio of 6:1 and 1.5% KOH wt/wt of oil. The optimum reaction conditions for the transesterification of the WCO via ultrasound technology applied in a continuous system in this study were: a reaction time of 30 min, 30 º / C, 6:1 methanol/oil ratio and a 0.75 wt% (KOH) catalyst concentration. The ultrasound assisted transesterification reactions performed at optimum conditions on the different oil samples led to higher yields of methyl esters (96.8, 98.32 and 97.65 % for WCO, SFO and SBO respectively) compared to methyl esters yields (90, 95 and 96 % for WCO, SFO and SBO respectively) obtained when using conventional batch procedures. A considerable increase in yields of the methyl esters in the ultrasound assisted reaction process were obtained at room temperature, in a remarkably short time span (completed in 30 min) and with a lower amount of catalyst (0.75 wt % KOH) while the results from the continuous jet loop process system showed even better results, at an optimum reaction condition of 25 min of reaction, a methanol: oil ratio of 4:1 and a catalyst amount of 0.5 wt%. This new jet loop process allowed an added advantage of intense agitation for an efficient separation and adequate purification of the methyl esters phase at a reduced time of 30 min. The use of homogeneous catalysts in conventional processes poses many disadvantages / heterogeneous catalysts on the other hand are attractive on the basis that their use could enable the biodiesel production to be more readily performed as a continuous process resulting in low production costs. Consequently, a solid base catalyst (KNO3/FA) prepared from fly ash (obtained from Arnot coal power station, South Africa) and a new zeolite, FA/Na-X synthesized from the same fly ash were used as solid base catalysts in the transesterification reactions in the conversion of a variety of oil feedstock with methanol to methyl esters. Since fly ash is a waste product generated from the combustion of coal for power generation, its utilization in this manner would allow for its beneficiation (as a catalytic support material and raw material for zeolite synthesis) in an environmentally friendly way aimed at making the transesterification process reasonably viable. Arnot fly ash (AFA) was loaded with potassium (using potassium nitrate as precursor) via a wet impregnation method while the synthesized zeolite FA/Na-X was ion exchanged with potassium (using potassium acetate as precursor) to obtain the KNO3/FA and FA/K-X catalysts respectively. Several analytical techniques were applied for characterization purposes. The results of the XRD and XRF showed that the AFA predominantly contained some mineral phases such as quartz, mullite, calcite and lime. The high concentration of CaO in AFA was apparent to be beneficial for the use of fresh fly ash as a support material in the heterogeneous catalysed transesterification reactions. XRD characterisation of KNO3/FA results indicated that the structure of KNO3/FA gradually changed with the increase in KNO3 loading. The catalyst function was retained until the loading of KNO3 was over 10 %. IR spectra showed that the KNO3 was decomposed to K2O on the fly ash support during preparation at a calcination temperature of 500 º / C. The CO2-TPD of the KNO3/FA catalysts showed that two basic catalytic sites were generated which were responsible for high catalytic abilities observed in the transesterification reactions of sunflower oil to methyl esters. On the other hand, XRD results for the as- received zeolite synthesized from AFA showed typical diffraction peaks of zeolite NaX. SEM images of the FA /NaX showed nano platelets unique morphology different from well known pyramidal octahedral shaped crystal formation of faujasite zeolites and the morphology of the FA /KX zeolite did not show any significant difference after ion exchange. The fly ash derived zeolite NaX (FA /NaX) exhibited a high surface area of 320 m2/g. The application of the KNO3/FA catalysts in the conversion reactions to produce methyl esters (biodiesel) via transesterification reactions revealed methyl ester yield of 87.5 % with 10 wt% KNO3 at optimum reaction conditions of methanol: oil ratio of 15:1, 5 h reaction time, catalyst amount of 15 g and reaction temperature 160 ° / C, while with the use of the zeolite FA/K-X catalyst, a FAME yield of 83.53 % was obtained for 8 h using the ion exchanged Arnot fly ash zeolite NaX catalyst (FA/KX) at reaction conditions of methanol: oil ratio of 6:1, catalyst amount of 3 % wt/wt of oil and reaction temperature of 65 º / C. Several studies have been carried out on the production of biodiesel using different heterogeneous catalysts but this study has been able to uniquely demonstrate the utilization of South African Class F AFA both as a catalyst support and as a raw material for zeolite synthesis / these catalyst materials subsequently applied sucessfully as solid base catalysts in the production of biodiesel.</p>
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Qualitative and Quantitative Analysis of Biodiesel Deposits Formed on a Hot Metal SurfaceWestberg, Emilie January 2013 (has links)
This thesis aims to investigate the formation of deposits from thermally degraded biodiesel on a hot metal surface under the influence of sodium or copper contaminations. Biodiesel or Fatty Acid Methyl Esters (FAMEs) is a widely utilized biofuel with the potential to replace fossil fuels, however, issues regarding the thermal and oxidative stability prevent the progress of biodiesel for utilization as vehicle fuel. The thermal degradation of biodiesel causes formation of deposits often occurring in the fuel injectors, which could result in reduced engine efficiency, increased emissions and engine wear. However, still have no standard method for evaluation of a fuels’ tendency to form deposits been developed. In this study biodiesel deposits have been formed on aluminum test tubes utilizing a Hot Liquid Process Simulator (HLPS), an instrument based on the principle of the Jet Fuel Thermal Oxidation Tester (JFTOT). Quantitative and qualitative analyses have been made utilizing an array of techniques including Scanning Electron Microscopy (SEM), Gas Chromatography Mass Spectrometry (GCMS) and Attenuated Total Reflectance Fourier Transform Infrared Spectrometry (ATR-FTIR). A multi-factorial trial investigating the effects of sodium hydroxide and copper contaminations at trace levels and the impact of a paraffin inhibitor copolymer additive on three different FAME products, two derived from rapeseed oil and one from waste cooking oil as well as a biodiesel blend with mineral diesel, was conducted.The results exhibited that FAMEs are the major precursor to deposit formation in diesel fuel. The SEM analyses exploited the nature of FAME deposits forming porous structures on hot metal surfaces. Sodium hydroxide proved to participate in the deposit formation by forming carboxylic salts. However, the copper contamination exhibited no enhancing effect on the deposits, possibly due to interference of the blank oil in which copper was received. The paraffin inhibitor functioning as a crystal modifier had significant reducing effect on the deposit formation for all biodiesel samples except for the FAME product derived from waste cooking oil. Further studies are needed in order to investigate the influence of glycerin and water residues to the biodiesel deposit formation. Mechanisms involving oxidative or thermal peroxide formation, polymerization and disintegration have been suggested as degradation pathways for biodiesel. The involvement of oxidation intermediates, peroxides, was confirmed by the experiments performed in this thesis. However, the mechanisms of biodiesel deposit formation are complex and hard to study as the deposits are seemingly insoluble. Nevertheless, ATR-FTIR in combination with JFTOT-processing has potential as standard method for evaluation of deposit forming tendencies of biodiesel.
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Development and Application of Kinetic Meshless Methods for Euler EquationsC, Praveen 07 1900 (has links)
Meshless methods are a relatively new class of schemes for the numerical solution of partial differential equations. Their special characteristic is that they do not require a mesh but only need a distribution of points in the computational domain. The approximation at any point of spatial derivatives appearing in the partial differential equations is performed using a local cloud of points called the "connectivity" (or stencil). A point distribution can be more easily generated than a grid since we have less constraints to satisfy.
The present work uses two meshless methods; an existing scheme called Least Squares Kinetic Upwind Method (LSKUM) and a new scheme called Kinetic Meshless Method (KMM). LSKUM is a "kinetic" scheme which uses a "least squares" approximation} for discretizing the derivatives occurring in the partial differential equations. The first part of the thesis is concerned with some theoretical properties and application of LSKUM to 3-D point distributions. Using previously established results we show that first order LSKUM in 1-D is positivity preserving under a CFL-like condition. The 3-D LSKUM is applied to point distributions obtained from FAME mesh. FAME, which stands for Feature Associated Mesh Embedding, is a composite overlapping grid system developed at QinetiQ (formerly DERA), UK, for store separation problems.
The FAME mesh has a cell-based data structure and this is first converted to a node-based data structure which leads to a point distribution. For each point in this distribution we find a set of nearby nodes which forms the connectivity. The connectivity at each point (which is also the "full stencil" for that point) is split along each of the three coordinate directions so that we need six split (or half or one-sided) stencils at each point. The split stencils are used in LSKUM to calculate the split-flux derivatives arising in kinetic schemes which gives the upwind character to LSKUM. The "quality" of each of these stencils affects the accuracy and stability of the numerical scheme. In this work we focus on developing some numerical criteria to quantify the quality of a stencil for meshless methods like LSKUM.
The first test is based on singular value decomposition of the over-determined problem and the singular values are used to measure the ill-conditioning (generally caused by a flat stencil). If any of the split stencils are found to be ill-conditioned then we use the full stencil for calculating the corresponding split flux derivative. A second test that is used is based on an accuracy measurement. The idea of this test is that a "good" stencil must give accurate estimates of derivatives and vice versa. If the error in the computed derivatives is above some specified tolerance the stencil is classified as unacceptable. In this case we either enhance the stencil (to remove disc-type degenerate structure) or switch to full stencil. It is found that the full stencil almost always behaves well in terms of both the tests. The use of these two tests and the associated modifications of defective stencils in an automatic manner allows the solver to converge without any blow up. The results obtained for a 3-D configuration compare favorably with wind tunnel measurements and the framework developed here provides a rational basis for approaching the connectivity selection problem.
The second part of the thesis deals with a new scheme called Kinetic Meshless Method (KMM) which was developed as a consequence of the experience obtained with LSKUM and FAME mesh. As mentioned before the full stencil is generally better behaved than the split stencils. Hence the new scheme is constructed so that it does not require split stencils but operates on a full stencil (which is like a centered stencil). In order to obtain an upwind bias we introduce mid-point states (between a point and its neighbour) and the least squares fitting is performed using these mid-point states. The mid-point states are defined in an upwind-biased manner at the kinetic/Boltzmann level and moment-method strategy leads to an upwind scheme at the Euler level. On a standard 4-point Cartesian stencil this scheme reduces to finite volume method with KFVS fluxes. We can also show the rotational invariance of the scheme which is an important property of the governing equations themselves.
The KMM is extended to higher order accuracy using a reconstruction procedure similar to finite volume schemes even though we do not have (or need) any cells in the present case. Numerical studies on a model 2-D problem show second order accuracy. Some theoretical and practical advantages of using a kinetic formulation for deriving the scheme are recognized. Several 2-D inviscid flows are solved which also demonstrate many important characteristics. The subsonic test cases show that the scheme produces less numerical entropy compared to LSKUM, and is also better in preserving the symmetry of the flow. The test cases involving discontinuous flows show that the new scheme is capable of resolving shocks very sharply especially with adaptation. The robustness of the scheme is also very good as shown in the supersonic test cases.
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