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Osborn, Helen. "Undesirable pinking in meat and meat model systems." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343321.
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Casanova, Luque Luis Enrique, Sánchez Camila Betsabé Manrique, Crispin Jurgen Alex Maldonado, Capillo Juanita Dalia Nieto, and Orosco Sheyla Milagros Yoplac. "Paleo Meat." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/652162.
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En el presente trabajo de investigación desarrollado en la Universidad Peruana de Ciencias Aplicadas a los estudiantes de modalidad PREGRADO, consiste en la aplicación de un plan para la puesta en marcha de un modelo de negocio de cortes de carne especiales para parrillas y complementos empaquetados al vacío. Dentro de los complementos tenemos una selección de salsas gourmet y embutidos artesanales preparado en base a una selección de finas hierbas, de esta manera Paleo Meat brindará una experiencia gastronómica de cortes en carnes y charcutería.
Paleo Meat posee como público objetivo a personas comprendidos de 25 a 55 años pertenecientes a un NSE A y B que residan en los distritos de la zona 7 y aledaños en lima metropolitana. En su mayoría pertenecen a la Población económicamente activa.
El producto será promocionado a través de plataformas virtuales, es decir, redes sociales como Facebook e Instagram. Así mismo, será comercializado a través de servicio de Courier tales como Rappi, Glovo, Uber Eats u otros.
Finalmente, el análisis financiero realizado como estudio de la empresa tenemos un costo de oportunidad del capital (COK) de 11.68%. De esta manera podemos concluir que, el desarrollo de la empresa CARNES Y CHARCUTERÍA SAC es viable económicamente.<br>In the present research work developed at the Peruvian University of Applied Sciences for undergraduate students, it consists in the application of a plan for the implementation of a business model of special cuts of meat for grills and vacuum-packed accessories. Within the complements we have a selection of gourmet sauces and artisanal sausages prepared based on a selection of fine herbs, in this way Paleo Meat will provide a gastronomic experience of cuts in meats and charcuterie.
Paleo Meat has as its target audience people between 25 and 55 years old belonging to an NSE A and B that reside in the districts of zone 7 and nearby in metropolitan Lima. They mostly belong to the economically active population.
The product will be promoted through virtual platforms, that is, social networks such as Facebook and Instagram. Likewise, it will be marketed through Courier service such as Rappi, Glovo, Uber Eats or others.
Finally, the financial analysis performed as a study of the company has an opportunity cost of capital (COK) of 11.68%. In this way we can conclude that, the development of the company CARNES Y CHARCUTERÍA SAC is economically viable.<br>Trabajo de investigación
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Shang, Xia. "Food safety impacts on U.S. domestic meat demand and international red meat trade." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32729.
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Doctor of Philosophy<br>Department of Agricultural Economics<br>Glynn Tonsor<br>Few things facing the U.S. meat industry in recent years have garnered more attention of economic researchers than food safety events, policies, and mitigation efforts. This dissertation has two main essays and themes focusing on both domestic and international food safety issues. Contributing new insights to this situation, the impacts of FSIS (Food Safety Inspection Service) recalls on consumer meat demand in the United States are estimated by a series of Rotterdam models in the first study using monthly grocery-scanner data. Multiple model specifications are employed to further assess effects across meat products and geographic regions. Recall variables are constructed separately as beef E. coli recall, beef non-E. coli recall, pork recall, and poultry recall variables to facilitate finer assessment of demand impacts. Results suggest beef E. coli recalls significantly reduce the demand for ground beef contemporaneously among most, but not all, regions in the United States. The ultimate finding of food safety effects neither being fully homogeneous nor entirely heterogeneous warrants appreciation.
In order to protect domestic consumers and meat industries from potential food safety hazards, some member countries of the WTO implement sanitary and phytosanitary (SPS) measures as non-tariff barriers. The second study focuses on investigating the determinants of red meat trade patterns and associated impacts of SPS regulations. This analysis uses multiple product-level gravity equation models and PPML (Poisson Pesudo Maximum-likelihood estimators to overcome sample selection bias and heteroscedasticity and examine the trade relationship among other factors. Results indicate that, trade values of frozen beef and pork are significantly reduced by the implementation of SPS measures. Also, the spillover effects across meat products on trade were detected which provides essential information to the meat industry, policy makers, and trade representatives.
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Piette, J. P. Gabriel (Jean-Paul Gabriel). "Bacterial adhesion to model meat surfaces." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70302.
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The adhesion of seven meat spoilage bacteria to model meat surfaces (thin fat and tendon slices) was studied in a specially designed flow chamber. In general, adhesion was not influenced by the physiological age of the cells and was not correlated with the cell surface characteristics (electrical charge, hydrophobicity) of the organisms. Also, adhesion data did not corroborate the predictions based on changes in the free energy of adhesion, calculated from contact angles and surface tension measurements. A more detailed study of the adhesion of Pseudomonas fluorescens to tendon was subsequently undertaken. Neither physiological activity nor the presence of flagella was found to be essential for adhesion. Selective chemical alterations of the cell surface pointed to no direct implication of carboxyl or amino groups in an adhesive bond with tendon. These groups may participate in adhesion, however, through electrostatic interactions as suggested from the variations of adhesion with ionic strength.
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Fedeniuk, Ricky Wayne. "Oxytetracycline degradation in model meat processing systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ27404.pdf.
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Thompson, Wyatt. "An econometric model of Japanese meat markets /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9904869.
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Obeng, George Boakye. "A Game Theoretical Model For Prevention of Meat Contamination at A Meat Packing House." University of Akron / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=akron1302800451.
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Mwangi, Rosemary Mustapha Azlin Hsieh Fu-hung. "Inactivation of wild type bacillus spores in a soy meat analog model by extrusion cooking." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/5763.
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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 2, 2009). Thesis advisor: Dr. Azlin Mustapha and Dr. Fu-Hung Hsieh. Includes bibliographical references.
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Arnold, Andrew Richard. "Lipid oxidation in a model system and in meat." Thesis, University of St Andrews, 1989. http://hdl.handle.net/10023/14168.
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Lipid oxidation is the main factor which limits the shelf-life of meat when held under frozen storage. Research undertaken used pork phospholipid liposomes as a model for studying lipid oxidation in meat. Oxidation was followed by monitoring the decrease in the phospholipid unsaturated fatty acyl chains. It was found that the greater the level of unsaturation of the phospholipid fatty acyl chain the greater was their susceptibility to peroxidation. However, the results were not consistent and several reasons for the variation in rate are provided. At ambient temperatures copper (II) was found to be pro-oxidant in the peroxidation of liposomes. At temperatures below 0°C the prooxidant activity of copper (II) was significantly reduced. However copper again became highly pro-oxidant if sodium chloride was present. It is suggested that salt controls the copper ion concentration at sub-zero temperatures as the pro-oxidant activity of copper (II) is reduced on increasing the copper (II) concentration from 0.9 to 90 ppm. Other experiments found sodium nitrite and pholyphosphate to act as antioxidant and that liposome structure was an important factor in the rate of peroxidation. Four storage trials on pork burgers were undertaken to determine whether salt was also pro-oxidant in the stability of pork when held under frozen storage. The oxidative deterioration of the meat was followed by the following methods of analysis:- 1. The decrease in the unsaturated acyl chains of both total lipid and phospholipid. 2. The change in the colour parameters of the meat using reflectance spectroscopy. 3. The analysis of neutral lipid oxidation products by HPLC. 4. The organoleptic qualities of the pork using a trained panel of food assessors. The results from these storage trails showed that the deterioration of pork was minimised by storing the burgers at lower temperatures within the range 0 to -30°C. Salt was found to accelerate the oxidative deterioration of both uncooked and cooked pork when stored at -20°C. Nitrite was found to exhibit some antioxidant behaviour and reduce the pro-oxidant effect of salt.
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Ness, M. R. "An econometric model of the United Kingdom poultry meat sector." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376130.
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Manning, L. J. "Development of a quality assurance model for poultry meat production." Thesis, Coventry University, 2008. http://curve.coventry.ac.uk/open/items/bd90e402-5959-3143-b469-4581341759c5/1.
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The study has defined the position with regard to existing and evolving United Kingdom (UK) and European Union (EU) legislation, world trade agreements and institutions, global trade in chicken meat and market Quality Assurance (QA) standards in a series of peer-reviewed published papers and working papers. The development of global food supply chains can be a key driver in the harmonisation of international legislation, product and private assurance standards. Indeed compliance with legislation and retailer requirements has been a key market driver in the development of private assurance standards. The key objectives of the research were to examine current assurance schemes within the integrated poultry meat supply chain and the influence of regulation and external market drivers within the integrated poultry meat supply chain; develop and test a QA model for the poultry meat supply chain with a view to both baseline and higher level standards including the development of a business benchmarking system utilising a pre-requisite programme (PRP) and key performance indicators (KPI); and to assess the ability of the QA model to deliver regulatory and policy compliance whilst meeting varied business and market needs for an internationally traded product. This study has shown that a QA model is capable of providing a framework within which the poultry meat supply chain can operate. The legislative and performance requirements have been translated into quantifiable performance indicators which can be used to measure supply chain performance. This can assist differentiation of products at the point of consumption and give a quantifiable measure of the extrinsic value that has been added. This approach will therefore aid the communication of the benefits of differing methods of poultry meat production and afford the consumer the opportunity to make a more informed choice when purchasing meat products.
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Chen, Gengjun. "Formation and inhibition of advanced glycation endproducts in meat and model systems." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34505.
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Doctor of Philosophy<br>Food Science Institute<br>J. Scott Smith<br>Advanced glycation endproducts (AGEs) are formed in many cooked meat products via Maillard browning reactions. Current research suggests consumption of these compounds may be a contributor to chronic diseases such as diabetes and heart diseases. Thus, information on the prevalence and inhibition of these compounds in food is desirable.
The first objective was to determine the AGE content, as determined as N[superscript]ε-carboxymethyllysine (CML) level, in cooked meat and fish prepared by general cooking methods recommended by U.S. Department of Agriculture, Food Safety and Inspection Service (USDA-FSIS). We found AGE was detected in all the cooked samples, but the levels depended on the different cooking conditions. Broiling and frying at higher cooking temperatures produced higher levels of CML and broiled beef contained the highest CML content (21.84 μg/g). However, the baked salmon (8.59 μg/g) and baked tilapia (9.72 μg/g) contained less CML as compared to the other samples.
In order to investigate the inhibitory effect of selected natural antioxidant on AGEs formation in cooked meat, four cereal brans, wheat (Jagger, JA), triticale (Spring Triticale, ST; Thundercale, TH), and Rye (RY) bran were added to beef patties before cooking. RY (42.0% inhibition), ST (27.5% inhibition), and TH (21.4% inhibition) brans significantly decreased CML formation compared with the control. The inhibition of CML was correlated to the water-holding activity (WHC) of the samples, and the radical scavenging activity of the brans.
The effect of cereal bran extracts (JA, ST, TH, and RY), was studied in a bovine serum albumin and glucose (BSA-GLU) model system. The ST extract significantly (P <0.05) inhibited CML formation compared to the control group. ST particularly contained vanillic acid (VA), chlorogenic acid (CHA), gentisic acid (GEA), and ferulic acid (FA), where GEA and CHA mitigated CML with an average percentage decrease of 29.6% for CHA and 51.1% for GEA. It therefore may be useful in preventing AGEs formation by using ST bran as a food addictive, which contains abundant phenolic acids.
In summary, current dietary AGEs database will provide important information for use in estimating AGEs exposure, and also these data demonstrate that a significantly reduced intake of dietary AGEs can be achieved by low heat AGE cooking methods such as baking, which can be used at home or in the meat industry. Cereal bran addition to meat products may reduce formation of AGEs that is a desired attribute for the processed meat products industry.
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Duke, John Killebrew. "Development of basic meat science standards for secondary agricultural education Delphi model /." Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1246558749/.
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Annor-Frempong, Irene Ewuraama. "The problem of boar taint : sensory and instrumental analyses in a model system and in pork." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389133.
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Lamine, Slim 1965. "A predictive model of shelf life enhancement for meat packed under modified atmospheres." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277920.
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A dynamic model of fresh beef packaged under modified atmospheres has been developed. This model links the change in meat color with the permeation of gases (O₂, CO₂, N₂) through the packaging film. Its viability is demonstrated with experimental data using muscle semimembranosus with which it was shown that color change of the meat surface and the change of headspace gas concentration were well described by the model. Moreover, the model parameters were obtained independently of the model itself through the literature. A major result of the model showed that surface color is independent of oxygen concentration above 5%. Moreover, under aseptic conditions and ambient atmosphere concentrations, shelf-life of muscle semimembranosus was shown to be 11 days with this value possibly being a minimum.
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Ransome, Kristin. "Intentions to engage in a meat-reduced diet: an application of the integrative model of behavioural prediction." Master's thesis, Faculty of Commerce, 2018. http://hdl.handle.net/11427/31014.
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The consumption of meat and meat products has been cited as the most critical area to be addressed if we are to meet a sustainable future diet, regarding the impact on climate change and health. The numerous sustainability concerns that have been raised have stimulated calls to reduce the quantity of meat people in general eat, and have created an on-going global debate among policymakers, academics and practitioners. This research makes use of the Integrative Model of Behavioural Prediction (IMBP) in order to isolate the key determinants of what drives the intentions of middle to upper-income South Africans to engage in a meat-reduced diet (MRD). A two-phase methodology was utilised, by firstly conducting an elicitation study to identify the salient beliefs present in the population, and secondly by conducting a population survey to quantify the cognitive foundation of this behaviour. The empirical results showed that the areas of cognition which most strongly predict whether one intends to engage in an MRD were instrumental attitude, experiential attitude and injunctive norms. This study makes three primary contributions. Firstly, a theoretical contribution, through providing insight into how behavioural themes and beliefs materialise into changes in meat-consumption. Secondly, marketing practitioners can benefit from the insight offered by IMBP, which is valuable as it helps to identify what behavioural shift is required to promote MRDs. Lastly, this study contributes to the methodology utilised when applying the IMBP by applying the model to dietary behaviour, which has received comparatively less attention in the past.
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Hussain, Faris A. "Formation of 4(5)-methylimidazole in processed meat and in glucose amino acid model system." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/18975.
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Doctor of Philosophy<br>Food Science Institute<br>J. Scott Smith<br>The International Agency for Research on Cancer (IARC) has classified 4(5)-methylimidazole (4-MeI) as a possible human carcinogen. Also, the National Toxicology Program (NTP) has concluded that 4-MeI is a probable cancer causing agent. Even though 4-MeI has been detected in several processed foods no research has been conducted to measure levels of 4-MeI in processed meat. A method using isobutylchloroformate (IBCF) and gas chromatography mass-spectrometry (GC-MS) was developed to detect and quantify 4-MeI in processed meat products. Levels of 4-MeI ranged from 0.04 to 1.01 μg/g with recovery of 94.76 to 103.94%.
Formation of 4-MeI in glucose-amino acid model system was studied. [subscript]D-Glucose (Glu) was mixed individually in equimolar concentrations of 0.05, 0.1, or 0.15 M and equal volume with [subscript]L-Alanine (Ala), [subscript]L-Arginine (Arg), Glycine (Gly), [subscript]L-Lysine (Lys), and [subscript]L-Serine (Ser); and the mixtures were heat treated at 60, 120, and 160°C for 1 h. Among all tested amino acids, Glu-Arg produced the highest level of 4-MeI. The Glu-Lys model system showed higher browning and lower concentrations of 4-MeI.
The effect of ascorbic acid (ASA), a strong antioxidant, was studied in the Glu-Arg model system. Four concentrations of ASA (0.0375, 0.075, 0.15, and 0.3 M) were mixed with 0.15 M equimolar of Glu-Arg and heat treated at 160°C for 1h. ASA inhibited formation of 4-MeI by 40.29, 69.94, 75.13, and 96.25% for the 0.0375, 0.075, 0.15, and 0.3 M concentrations. Contrarily, ascorbic acids increased the browning in all treatments compared to control treatment by 10.67, 15.47, 18.4, and 28.8% for the 0.0375, 0.075, 0.15, and 0.3 M concentrations. Adding ASA to processed food may reduce formation of 4-MeI and increase the browning that is a desired attribute to processed meat products.
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Ellis, Christina M. "An integrated model for conservation case study on the role of women in the commercial bushmeat trade in Cameroon /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0007/MQ59545.pdf.
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Alaoui, Oussama. "Trade policy simulation and welfare analysis using a partial equilibrium model : the case of bovine meat in Morocco." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/785.
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Malindi, Happy Edward. "A framework to measure customers' perceptions on the quality of red meat / H.E. Malindi." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4461.
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This preliminary study investigated the factors which influence consumer choice of beef. A questionnaire and sensory evaluation considered the level of importance which consumers attached to the sensory (intrinsic attributes) properties of beef as compared to extrinsic factors. It was found that consumers use sensory properties to predict the freshness and overall eating quality, but they can also misinterpret the quality cues.
Consumers made it clear that the freshness and the place of purchase played a prominent role in their decision to purchase red meat because they perceive the retailer to be an integral part of the overall quality assessment with regard to the purchase process of mutton and beef.
The Total Food Quality Model is used as the frame of reference for analysing the way in which consumers perceive meat quality. The way in which consumers form expectations about the quality at the point of purcha7se, based on their own experience and information cues available in the shopping environment, is described as well as the way in which quality is experienced in the home during and after meal preparation. The relationship between quality expectations and quality experience and its implications for consumer satisfaction and repeat purchase intent is addressed.
The study collected data by means of a questionnaire to evaluate the quality perceptions of beef. Cronbach alpha as reliability coefficient recorded high levels of reliability and the factor analysis revealed that only one factor, namely that of quality considerations is present in the analysis. Furthermore, the building on the insights obtained on subjective quality perception, possibilities for consumer–oriented product development in the meat sector are addressed. Issues dealt with here are branding, differentiation by taste, healthiness and convenience.<br>Thesis (M.Sc. (Computer Science))--North-West University, Potchefstroom Campus, 2011.
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JÃnior, Josà Freire. "COMPARATIVE ANALYSIS OF THE IMPACT OF EXCHANGE RATE ON BRAZILIAN EXPORTS OF MEAT, FROM 1989 TO 2009." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5157.
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O objeto dessa dissertaÃÃo à conhecer a influÃncia do cÃmbio sobre as exportaÃÃes brasileiras de carnes bovina, suÃna e de frango e, posteriormente, comparar os resultados encontrados, decorrentes da obtenÃÃo das elasticidades-cÃmbio e elasticidades-renda mundial de curto e longo prazo. Verificar se houve quebra estrutural no perÃodo referente à anÃlise, jà que, neste mesmo perÃodo, a economia brasileira sofreu diversas turbulÃncias e mudanÃas de regimes cambiais. Para obter os resultados esperados, foram empregados mÃtodos de sÃries de tempo, teste de raiz unitÃria, teste de cointegraÃÃo de Johansen, o modelo autorregressivo vetorial (VAR), vetor de correÃÃo de erros (VEC), funÃÃo impulso-resposta, decomposiÃÃo da variÃncia dos erros de previsÃo e teste de causalidade de Granger. O perÃodo escolhido abrange abril de 1989 a marÃo de 2009 distribuÃdo em 80 observaÃÃes trimestrais. Os resultados indicam que as sÃries que apresentam raÃzes unitÃrias sÃo todas integradas de ordem um em nÃvel e mostram uma relaÃÃo de longo prazo entre elas, de acordo com o teste de cointegraÃÃo de Johansen. Os coeficientes dos modelos estimados apresentaram resultados compatÃveis com a teoria econÃmica quando tratados sob a forma de elasticidades; os resultados mostraram, tambÃm, a forte influÃncia da renda mundial sobre as exportaÃÃes de carnes quando comparados com a taxa de cÃmbio. A relaÃÃo entre as variÃveis indicou que o sentido da causalidade à unidirecional, ou seja, a taxa de cÃmbio real e a renda mundial afetam as exportaÃÃes de carnes (gado, frango e suÃna), mas a recÃproca nÃo à verdadeira. Por fim cabe salientar, que a importÃncia do estudo de comparaÃÃo visa entender a particularidade de cada tipo de carne estudado para efeito de planejamento e desenvolvimento de polÃticas econÃmicas adequadas.<br>The object of that dissertation is to know the influence of the exchange on the bovine Brazilian exports of meats, suÃna and of chicken and, later, to compare the found results, mainly the elasticity-exchange and world elasticity-income of short and soon period. Verify if there was structural break in the period regarding analysis, since, in this period, the Brazilian economy suffered several turbulences and changes of exchange regimes. To obtain the expected results, they were employees methods of series of time, test of unitary root, test of cointegraÃÃo of Johansen, the vectorial autoregressive model (VAR), error correction vector (VEC), function pulse-answer, decomposition of the variance of the forecast mistakes and test of causality of Granger. The chosen period includes April from 1989 to March of 2009 distributed in 80 observations quarterly. The results indicate that the series present unitary roots, they are integrated of order an and they present a relationship of soon period among them, in agreement with the test of cointegraÃÃo of Johansen. The coefficients of the dear models presented compatible results with the economical theory when treaties in the form of elasticities, the results also showed to strong influence of the world income on the exports of meats when compared with the exchange rate. The relationship among the variables indicated that the sense of the causality is unidirecional, in other words, the real exchange rate and the world income affect the exports of meats (cattle, chicken and suÃna), but the reverse is not true. Finally he/she fits to point out, that the importance of the comparison study seeks to understand the particularity of each one of the meats studied for planning effect and development of appropriate economic policies.
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Ré, Ana de Almeida. "Aplicação de infusões de ervas aromáticas para substituição de aditivos químicos num modelo de carne fermentado." Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2020. http://hdl.handle.net/10400.5/20364.
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Dissertação de Mestrado Integrado em Medicina Veterinária<br>Atualmente, existe uma procura crescente por conservantes naturais, sobretudo de origem vegetal, para reduzir o conteúdo de nitrito e/ou nitrato (aditivos químicos) em produtos curados à base de carne. Com este trabalho pretendeu-se estudar formas de substituir o uso destes aditivos químicos por infusões de quatro ervas aromáticas (Manjericão Rubra, Tomilho Limão, Orégãos vulgar e Sálvia Ananás), como fonte natural de nitrato, avaliando a evolução da microbiota tecnológica, características físico-químicas e sensoriais (baseado numa escala Just about right), num modelo cárneo armazenado em refrigeração durante quatro dias. Foram realizadas seis formulações, com diferentes concentrações de nitrato de sódio (mg) por quilograma de produto cárneo, correspondentes a: (C) Controlo com 0 ppm; (T1) Manjericão rubra com 70 ppm; (T2) Tomilho limão com 70 ppm; (T3) Manjericão rubra com 100 ppm; (T4) Sálvia ananás com 100 ppm; (T5) Orégãos com 100 ppm. Os modelos cárneos foram analisados realizando-se contagens de Aeróbios totais a 30 ºC, Enterobacteriaceae, Bactérias Ácido Lácticas (BAL) e Staphylococcus coagulase negativa (SCN). Foram ainda determinados os teores de nitratos, nitritos, cloretos, a cor e o pH.
As infusões com sálvia ananás mostraram ter um maior conteúdo de nitrato (63.124 mg/100ml) em comparação com infusões de tomilho limão e orégãos. O modelo cárneo T4 apresentou uma maior quantidade de nitratos (média 16.91 mg/kg). Este produto modelo após um período de 2 para 4 dias de armazenamento a 4 ºC, apresentou valores de nitrito de 3.93 mg/kg, onde se observou que a cor após cozedura teve um aumento da coordenada a* no dia 4, demonstrando uma cor mais rosada/avermelhada, indicativo do desenvolvimento do nitrosohemocromogénio. Além disso na caracterização sensorial do produto modelo não se notou nenhum aroma a ervas ou especiarias, exibindo sabores e cheiros neutros. Estes resultados indicam que os ingredientes naturais, como a infusão de sálvia ananás, podem ser possivelmente utilizados como alternativa a aditivos químicos na cura tradicional. Contudo, é necessária mais investigação para avaliar o impacto sensorial e microbiológico deste ingrediente quando utilizado em produtos curados à base de carne com novas formulações e com a adição de novos condimentos.<br>ABSTRACT - Application of aromatic plants infusions to replace chemical additives in a fermented meat model - Currently, there is an increasing demand for natural preservatives, mainly of vegetable origin, to reduce the content of nitrite and/or nitrate (chemical additives) in cured meat products. This work aimed to study ways to replace the use of these chemical additives by infusions of four aromatic plants (Red Basil, Lemon Thyme, Common Oregano and Pineapple Sage), as a natural source of nitrate, evaluating the evolution of technological microbiota, physical-chemical and sensory characteristics (based on a Just about right scale), in a meat model stored in refrigeration for four days. Six formulations were performed, with different concentrations of sodium nitrate (mg) per kilogram of meat product, corresponding to (C) 0 ppm control; (T1) 70 ppm red basil; (T2) 70 ppm lemon thyme; (T3) 100 ppm red basil; (T4) 100 ppm pineapple sage; (T5) 100 ppm common oregano. The meat models were analysed by performing total Aerobic counts at 30 ºC, Enterobacteriaceae, Lactic Acid Bacteria (BAL) and Staphylococcus coagulase negative (SCN). The levels of nitrates, nitrites, chlorides, colour and pH were also determined.
Pineapple Sage infusions showed a higher nitrate content (63,124 mg/100ml) compared to lemon thyme and common oregano infusions. The T4 meat model showed a higher nitrate content (mean 16.91 mg/kg). This model product after a period of 2 to 4 days of storage at 4 ºC, showed nitrite values of 3.93 mg/kg, where it was observed that the colour after cooking had an increase of the a* coordinate on day 4, showing a pinker/redder colour, indicative of the development of nitrosohemochromogen. In addition, the sensory characterization of the model product did not show any herbs or spices aroma, presenting neutral flavours and smells. These results indicate that natural ingredients, such as pineapple sage infusion, can possibly be used as an alternative to chemical additives in traditional curing. However, further research is needed to assess the sensory and microbiological impact of this ingredient when used in cured meat products with new formulations and the addition of new condiments.<br>N/A
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Allen, Karin. "A Novel Role for Non-Heme Iron in Myoglobin Oxidation: An Examination of the Antioxidant Effects of Iron Chelating Compounds in Meat and Myoglobin Model Systems." DigitalCommons@USU, 2009. https://digitalcommons.usu.edu/etd/374.
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Myoglobin (Mb) oxidation, and the subsequent browning, is the primary basis for consumer rejection of fresh retail beef. Considerable effort has been directed by the industry towards the development of techniques that can enhance color stability. However, the underlying mechanism of Mb oxidation has been studied extensively, but is still not entirely understood. It is known that chelation of iron and copper delays Mb oxidation and browning, but a clear role for these metals has not been established in any current Mb oxidation mechanism. The objective of the current study was to examine the possibility that iron plays a more direct role in Mb oxidation, and that metal chelators such as milk mineral (MM) and sodium tripolyphosphate can inhibit this action. MM, a colloidal calcium phosphate of large molecular weight and undetermined structure, was demonstrated to be a high-affinity iron chelator. Non-heme iron was found to stimulate Mb oxidation even in the absence of lipid, showing for the first time that the role of ferrous iron was not limited to promoting lipid oxidation, but instead has a yet-to-be determined role as a pro-oxidant factor in Mb oxidation. Ferrous iron was found to promote Mb oxidation under standard atmospheric conditions, while in high oxygen systems this effect was not seen. Addition of catalase did not affect Mb oxidation. However, in iron-containing systems, catalase significantly slowed Mb oxidation, while MM addition completely reversed the stimulatory effect of added iron. Type I radical-quenching antioxidants were found to rapidly reduce ferric iron to the ferrous form. This strong reducing ability accounted for the pro-oxidant effects of rosmarinic acid and eugenol in the lipid-free Mb model system. In raw ground beef, Type I antioxidants were highly effective at preventing Mb oxidation in the presence of lipid. Of the Type II chelators examined, only MM was able to delay Mb oxidation as well as the Type I antioxidants, possibly because it is not as susceptible to enzymatic hydrolysis.
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Trefan, Laszlo. "Development of empirical models for pork quality." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5761.
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Pork quality is an important issue for the whole meat chain, from producers, abattoirs, retailers through to costumers and is affected by a web of multi-factorial actions that occur throughout the pork production chain. A vast amount of information is available on how these diverse factors influence different pork quality traits. However, results derived from individual studies often vary and are in some cases even contradictory due to different experimental designs or different pork quality assessment techniques or protocols. Also, individual influencing factors are often studied in isolation, ignoring interacting effects. A suitable method is therefore required to account for a range of interacting factors, to combine the results from different experiments and to derive generic response-laws. The aim of this thesis was to use meta-analyses to produce quantitative, predictive models that describe how diverse factors affect pork quality over a range of experimental conditions.
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Moura, Sandra Vieira de. "Uso de modelo experimental para estudos relacionados ao estresse animal." Universidade Federal de Pelotas, 2015. http://repositorio.ufpel.edu.br:8080/handle/prefix/3284.
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Previous issue date: 2015-04-30<br>O estresse é um tema de relevante importância tanto para a área humana quanto animal. Animais produtores de carne são submetidos a diferentes fatores pré-abate. Esses fatores estressantes podem causar alterações fisiológicas que conduzem a um efeito prejudicial na qualidade final da carne. No Brasil, o mercado da carne ovina apresenta-se em ascensão, especialmente nos países em desenvolvimento, onde ocorre o crescimento econômico dos consumidores e o aumento da demanda. Neste contexto, realizou-se uma revisão bibliográfica dos últimos 40 anos, a qual aborda o manejo pré-abate, aspectos do comportamento e suas consequências na qualidade final da carne. Em um segundo capítulo, realizou-se um estudo com os objetivos de: (1) Descrever e padronizar a curva de pH da transformação em carne dos músculos Triceps brachii, Longissimus dorsi e Biceps femoralis de ratos submetidos a condições normais de criação desde a eutanásia até 24 horas post-mortem; (2) determinar se a análise em cada músculo altera significativamente a curva de pH; (3) determinar se o estresse pela contensão dos ratos no período ante mortem causa alterações qualitativas na carne e se afeta o tempo e os valores de pH necessários para a transformação do músculo em carne. Para a determinação da curva de pH muscular foram utilizados 12 ratos machos da linhagem Wistar, os animais sofreram eutanásia e as carcaças foram colocadas sob refrigeração para as aferições do pH muscular. Outro grupo de 12 animais foi submetido ao estresse por contensão e após foi realizada a eutanásia, seguido das avaliações de pH. Os resultados indicam que: (1) os valores de queda do pH muscular post mortem de ratos apresentam um ritmo semelhante às espécies comerciais; (2) os valores médios de pH muscular nos 3 grupos musculares não apresentam diferenças significativas em todos os períodos analisados; (3) as médias de pH muscular apresentam diferenças significativas da hora 0 até 6 horas após o abate, quando o valor mínimo de pH muscular é determinado. Assim, conclui-se, embora sejam conhecidos diferentes fatores pré-abate causadores de alterações fisiológicas que culminem com efeitos prejudiciais para a qualidade final da carne, ainda existem poucos métodos confiáveis, de fácil execução e não invasivos para detectar estresse em animais, padronizados até o momento. Os ratos são um modelo promissor para detectar alterações post-mortem, pois o decréscimo do pH muscular segue os valores e tempo semelhantes ao que ocorre nas espécies comerciais.<br>Stress is a topic relevant importance to both human and animal area. Animal meat producers are subjected to different pre-slaughter factors from the production unit to the slaughterhouse. These stressors factors to animals may cause physiological changes leading to an adverse effect on the final quality of the meat. In Brazil, in last years, sheep meat is a growing market, especially in developing countries, where economic growth more abundant, and increasingly demanding, consumers. In this contest, we conducted a literature review in the last 40 years, that addresses to slaughter handling of these animals, aspects of ovine behavior, and its consequences on final meat quality. In the second chapter, there was a study with the objectives of (1) to describe and standardize the pH curve transformation into meat muscle Triceps brachii, Longissimus dorsi and Biceps femoralis of rats subjected to normal breeding conditions from euthanasia to 24 hours post-mortem; (2) to determine whether the analysis in each muscle modify significantly the pH curve; (3) to determine whether the stress by rats restraining in the ante-mortem period cause qualitative changes in meat and affects the time and pH values for the transformation of muscle in meat. For the determination of muscle pH curves were used 12 male Wistar rats, and animals were euthanized and the carcasses were placed under refrigeration for measurements of pH. Another group of 12 animals was subjected to stress by restraining and after euthanasia was performed the pH evaluations. The results indicate that: (1) the post-mortem muscle pH values in rats show a downward trend similar commercial species; (2) the average values of muscle pH in the three muscle groups do not differ significantly in all the analyzed periods; (3) The medium muscle pH are significant differences between time 0 to 6 hours after slaughter, when the minimum value is determined. Thus, we conclude that although known different pre-slaughter factors that may cause physiological changes that culminate with detrimental effects on the final quality of the meat, there are few reliable methods, easy to perform and non-invasive to detect this stress in animals were standardized until now. Rats are a promising experimental model to detect post-mortem changes, because the decrease in the muscle pH follows the values and time similar to what happens to the commercial species.
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Guermazi, Mahdi. "In-Vitro Biological Tissue State Monitoring based on Impedance Spectroscopy." Doctoral thesis, Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-206710.
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The relationship between post-mortem state and changes of biological tissue impedance has been investigated to serve as a basis for developing an in-vitro measurement method for monitoring the freshness of meat. The main challenges thereby are the reproducible measurement of the impedance of biological tissues and the classification method of their type and state. In order to realize reproducible tissue bio-impedance measurements, a suitable sensor taking into account the anisotropy of the biological tissue has been developed. It consists of cylindrical penetrating multi electrodes realizing good contacts between electrodes and the tissue. Experimental measurements have been carried out with different tissues and for a long period of time in order to monitor the state degradation with time. Measured results have been evaluated by means of the modified Fricke-Cole-Cole model. Results are reproducible and correspond to the expected behavior due to aging. An appropriate method for feature extraction and classification has been proposed using model parameters as features as input for classification using neural networks and fuzzy logic. A Multilayer Perceptron neural network (MLP) has been proposed for muscle type computing and the age computing and respectively freshness state of the meat. The designed neural network is able to generalize and to correctly classify new testing data with a high performance index of recognition. It reaches successful results of test equal to 100% for 972 created inputs for each muscle. An investigation of the influence of noise on the classification algorithm shows, that the MLP neural network has the ability to correctly classify the noisy testing inputs especially when the parameter noise is less than 0.6%. The success of classification is 100% for the muscles Longissimus Dorsi (LD) of beef, Semi-Membraneous (SM) of beef and Longissimus Dorsi (LD) of veal and 92.3% for the muscle Rectus Abdominis (RA) of veal. Fuzzy logic provides a successful alternative for easy classification. Using the Gaussian membership functions for the muscle type detection and trapezoidal member function for the classifiers related to the freshness detection, fuzzy logic realized an easy method of classification and generalizes correctly the inputs to the corresponding classes with a high level of recognition equal to 100% for meat type detection and with high accuracy for freshness computing equal to 84.62% for the muscle LD beef, 92.31 % for the muscle RA beef, 100 % for the muscle SM veal and 61.54% for the muscle LD veal<br>Auf der Basis von Impedanzspektroskopie wurde ein neuartiges in-vitro-Messverfahren zur Überwachung der Frische von biologischem Gewebe entwickelt. Die wichtigsten Herausforderungen stellen dabei die Reproduzierbarkeit der Impedanzmessung und die Klassifizierung der Gewebeart sowie dessen Zustands dar. Für die Reproduzierbarkeit von Impedanzmessungen an biologischen Geweben, wurde ein zylindrischer Multielektrodensensor realisiert, der die 2D-Anisotropie des Gewebes berücksichtigt und einen guten Kontakt zum Gewebe realisiert. Experimentelle Untersuchungen wurden an verschiedenen Geweben über einen längeren Zeitraum durchgeführt und mittels eines modifizierten Fricke-Cole-Cole-Modells analysiert. Die Ergebnisse sind reproduzierbar und entsprechen dem physikalisch-basierten erwarteten Verhalten. Als Merkmale für die Klassifikation wurden die Modellparameter genutzt
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Bäckström, Fredrik, and Anders Ivarsson. "Meta-Model Guided Error Correction for UML Models." Thesis, Linköping University, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8746.
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<p>Modeling is a complex process which is quite hard to do in a structured and controlled way. Many companies provide a set of guidelines for model structure, naming conventions and other modeling rules. Using meta-models to describe these guidelines makes it possible to check whether an UML model follows the guidelines or not. Providing this error checking of UML models is only one step on the way to making modeling software an even more valuable and powerful tool.</p><p>Moreover, by providing correction suggestions and automatic correction of these errors, we try to give the modeler as much help as possible in creating correct UML models. Since the area of model correction based on meta-models has not been researched earlier, we have taken an explorative approach. </p><p>The aim of the project is to create an extension of the program MetaModelAgent, by Objektfabriken, which is a meta-modeling plug-in for IBM Rational Software Architect. The thesis shows that error correction of UML models based on meta-models is a possible way to provide automatic checking of modeling guidelines. The developed prototype is able to give correction suggestions and automatic correction for many types of errors that can occur in a model.</p><p>The results imply that meta-model guided error correction techniques should be further researched and developed to enhance the functionality of existing modeling software.</p>
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Guermazi, Mahdi. "In-Vitro Biological Tissue State Monitoring based on Impedance Spectroscopy." Doctoral thesis, Universitätsverlag der Technischen Universität Chemnitz, 2016. https://monarch.qucosa.de/id/qucosa%3A20484.
Full textAbstract:
The relationship between post-mortem state and changes of biological tissue impedance has been investigated to serve as a basis for developing an in-vitro measurement method for monitoring the freshness of meat. The main challenges thereby are the reproducible measurement of the impedance of biological tissues and the classification method of their type and state.
In order to realize reproducible tissue bio-impedance measurements, a suitable sensor taking into account the anisotropy of the biological tissue has been developed. It consists of cylindrical penetrating multi electrodes realizing good contacts between electrodes and the tissue. Experimental measurements have been carried out with different tissues and for a long period of time in order to monitor the state degradation with time. Measured results have been evaluated by means of the modified Fricke-Cole-Cole model. Results are reproducible and correspond to the expected behavior due to aging. An appropriate method for feature extraction and classification has been proposed using model parameters as features as input for classification using neural networks and fuzzy logic.
A Multilayer Perceptron neural network (MLP) has been proposed for muscle type computing and the age computing and respectively freshness state of the meat. The designed neural network is able to generalize and to correctly classify new testing data with a high performance index of recognition.
It reaches successful results of test equal to 100% for 972 created inputs for each muscle. An investigation of the influence of noise on the classification algorithm shows, that the MLP neural network has the ability to correctly classify the noisy testing inputs especially when the parameter noise is less than 0.6%. The success of classification is 100% for the muscles Longissimus Dorsi (LD) of beef, Semi-Membraneous (SM) of beef and Longissimus Dorsi (LD) of veal and 92.3% for the muscle Rectus Abdominis (RA) of veal.
Fuzzy logic provides a successful alternative for easy classification. Using the Gaussian membership functions for the muscle type detection and trapezoidal member function for the classifiers related to the freshness detection, fuzzy logic realized an easy method of classification and generalizes correctly the inputs to the corresponding classes with a high level of recognition equal to 100% for meat type detection and with high accuracy for freshness computing equal to 84.62% for the muscle LD beef, 92.31 % for the muscle RA beef, 100 % for the muscle SM veal and 61.54% for the muscle LD veal.<br>Auf der Basis von Impedanzspektroskopie wurde ein neuartiges in-vitro-Messverfahren zur Überwachung der Frische von biologischem Gewebe entwickelt. Die wichtigsten Herausforderungen stellen dabei die Reproduzierbarkeit der Impedanzmessung und die Klassifizierung der Gewebeart sowie dessen Zustands dar. Für die Reproduzierbarkeit von Impedanzmessungen an biologischen Geweben, wurde ein zylindrischer Multielektrodensensor realisiert, der die 2D-Anisotropie des Gewebes berücksichtigt und einen guten Kontakt zum Gewebe realisiert. Experimentelle Untersuchungen wurden an verschiedenen Geweben über einen längeren Zeitraum durchgeführt und mittels eines modifizierten Fricke-Cole-Cole-Modells analysiert. Die Ergebnisse sind reproduzierbar und entsprechen dem physikalisch-basierten erwarteten Verhalten. Als Merkmale für die Klassifikation wurden die Modellparameter genutzt.
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Nazir, Jawad [Verfasser]. "Persistence of H4N6, H5N1, and H6N8 avian influenza viruses, H1N1 human influenza virus, and two model viruses (NDV and ECBO) in various types of water, lake sediment, duck feces, and meat / Jawad Nazir." Gießen : Universitätsbibliothek, 2011. http://d-nb.info/1062973151/34.
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Kajero, Olumayowa T. "Meta-model assisted calibration of computational fluid dynamics simulation models." Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/813857/.
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Computational fluid dynamics (CFD) is a computer-based analysis of the dynamics of fluid flow, and it is widely used in chemical and process engineering applications. However, computation usually becomes a herculean task when calibration of the CFD models with experimental data or sensitivity analysis of the output relative to the inputs is required. This is due to the simulation process being highly computationally intensive, often requiring a large number of simulation runs, with a single simulation run taking hours or days to be completed. Hence, in this research project, the kriging meta-modelling method was coupled with expected improvement (EI) global optimisation approach to address the CFD model calibration challenge. In addition, a kriging meta-model based sensitivity analysis technique was implemented to study the model parameter input-output relationship. A novel EI measure was developed for the sum of squared errors (SSE) which conforms to a generalised chi-square distribution, where existing normal distribution-based EI measures are not applicable. This novel EI measure suggested the values of CFD model parameters to simulate with, hence minimising SSE and improving the match between simulation and experiments. To test the proposed methodology, a non-CFD numerical simulation case of the semi-batch reactor was considered as a case study which confirmed a saving in computational time, and an improvement of the simulation model with the actual plant data. The usefulness of the developed method has been subsequently demonstrated through a CFD case study of a single-phase flow in both a straight type and convergent-divergent type annular jet pump, where both a single turbulent model parameter, C_μ and two turbulent model parameters, C_μ and C_2ε where considered for calibration. Sensitivity analysis was subsequently based on C_μ as the input parameter. In calibration using both single and two model parameters, a significant improvement in the agreement with experimental data was obtained. The novel method gave a significant reduction in simulation computational time as compared to traditional CFD. A new correlation was proposed relating C_μ to the flow ratio, which could serve as a guide for future simulations. The meta-model based calibration aids exploration of different parameter combinations which would have been computationally challenging using CFD. In addition, computational time was significantly reduced with kriging-assisted sensitivity analysis studies which explored effect of different C_μ values on the output, the pressure coefficient. The numerical simulation case of the semi-batch reactor was also used as a basis of comparison between the previous EI measure and the newly proposed EI measure, which overall revealed that the latter gave a significant improvement at fewer number of simulation runs as compared to the former. The research studies carried out has hence been able to propose and successfully demonstrate the use of a novel methodology for faster calibration and sensitivity analysis studies of computational fluid dynamics simulations. This is essential in the design, analysis and optimisation of chemical and process engineering systems.
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Popaiz, Alessandro <1987>. "Business Meta Model: A Structured Framework for Business Models Representation." Master's Degree Thesis, Università Ca' Foscari Venezia, 2013. http://hdl.handle.net/10579/2390.
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Given the central role of Business Models in company characterization, it is not surprising that a great deal of effort has been spent in studying suitable representations for them. Most of the proposed models, however, pursue a semi-formal human-readable graphical paradigm that is mainly meant to be discussed among stakeholders, rather than to be easily handled by information systems. In this paper we introduce a formal meta model that aspires to be general enough to capture the expressiveness of most currently adopted paradigms. At the same time, each produced Business Model instance is regular and structured enough to be processed through automated algorithms. Specifically, data are organized as a structured graph, allowing for the adoption of well-known graph-based mining techniques. The ability of the framework to deal with real-world scenarios is assessed by modelling several actual companies. Further, some examples of data processing are given, specifically with the aim of spotting common patterns within a data base of Business Models.
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Musavu-Ndob, Aïchatou. "Mesures, modélisation, prédiction des propriétés physico-chimiques dans les aliments à l'aide d'un modèle thermodynamique : application aux produits carnés et aux produits laitiers." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22682/document.
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Le développement de simulateurs de procédés alimentaires est limité par le manque d’outils permettant de prédire les propriétés physicochimiques (pH, aw, Eh) dans les aliments. Les aliments sont généralement des milieux très complexes contenant un nombre élevé de constituants (eau, solvants organiques, solides dissous, gaz dissous, espèces ioniques, macromolécules), et ces propriétés sont essentielles pour caractériser leur qualité technologique, sanitaire et organoleptique. Cependant, elles évoluent au cours d’un procédé de transformation ou de conservation. La prédiction de ces propriétés physicochimiques passe par la détermination de potentiels chimiques. Une approche de modélisation basée sur la thermodynamique est utilisée pour prédire l’évolution du pH et de l’aw de produits carné et produits laitiers dans certaines conditions rencontrées en industrie alimentaire. En s’appuyant sur le modèle ULPDHS développé par Achard en 1992 pour les milieux liquides, ce travail a nécessité la création de molécules fictives à ayant le même comportement que les aliments modélisés. La cohérence entre les données expérimentales et les données prédites est satisfaisante, le modèle thermodynamique permet de prédire correctement le pH et l’aw des différents milieux étudiés. Cependant l’intégration du modèle thermodynamique dans un simulateur de procédé nécessite la création d’un réseau de neurone mimétique du modèle thermodynamique. En conséquent a été développé un réseau de neurones dont les sorties sont identiques aux sortie du modèle thermodynamique. Ainsi il est possible d’intégrer les résultats du modèles thermodynamique dans un simulateur de procédé sans trop rallonger les temps de simulations. Les résultats obtenus dans ce travail peuvent être une aide importante à la formulation de nouveaux produits. Le modèle étant entièrement prédictif, il est possible de déterminer l’effet d’une modification de composition de l’aliment sur le pH et l’aw<br>The development of food process simulators is actually limited by absence of tools that can predict de evolution of the physical-chemical properties (pH, aw, Eh) in food. Food are generallymulticomponent medias (including water, organic solvents, dissolved solids, dissolved gases, ionic species, macromolecules), and these properties are essential to characterize technological, sanitary and organoleptic qualities. However, these physical-chemical properties change during transformation or preservation process. The prediction of these properties requires the determination of chemical potentials. Thermodynamic approach is used to predict pH and water activity of meat and dairy products in different condition encountered in the food industry. Based on the model ULPDHS developed by Achard in 1992 for liquid medias, this work required the creation of fictive molecule who have the same behavior as modeled food. Consistency between the experimental data and the predicted data is very satisfactory, the thermodynamic model correctly predict the pH and aw of different products studied. The integration of the thermodynamic model in a process simulator requires the creation of a mimetic neural network. Therefore, was developed a neural network whose outputs are identical to the output of the thermodynamic model. So it is possible to integrate the results of thermodynamic models in a process simulator without too lengthen the time simulations. The results obtained in this work can be an important aid to the formulation of new products. The model is completely predictive and it is possible to determine the effect of a change in the composition of the feed on the pH and aw
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Skowyra, Monika. "Antioxidant properties of extracts from selected plant materials (Caesalpinia spinosa, Perilla frutescens, Artemisia annua and Viola wittrockiana) in vitro and in model food systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/284828.
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Phenolic compounds, ubiquitous in plants, are of considerable interest and are increasingly becoming a subject of intensive research due to their bioactive properties such as antioxidant, antimicrobial, anti-mutagenic, anti-viral and anti-inflammatory activity. The objective of this research was to determine the antioxidant activity of extracts from selected plant materials, namely Caesalpinia spinosa, Perilla frutescens, Artemisia annua and Viola wittrockiana Gams. Plant material extracts were studied by in vitro methods, such as Total Phenolic Content, the measurement of scavenging capacity against ABTS cation and AAPH radicals, and the ferric reducing antioxidant power (FRAP).
Many in vitro methods, such as ABTS, ORAC or FRAP assay, have been developed to evaluate antioxidant activity. Unfortunately, these methods often correlate poorly with the ability to inhibit oxidative deterioration of foods because the in vitro assays do not account for factors such as the physical location of the antioxidant, its interaction with other food components, and environmental conditions. To evaluate accurately the potential of antioxidants in foods, models must be developed that resemble conditions expected in food products. This study outlines model systems for the evaluation of natural antioxidants in two types of food: oil-in-water emulsions and meat model systems.
In addition, in all analyzed samples the content of the main phenolic compounds were determine using techniques such as high performance liquid chromatography (HPLC) or liquid chromatography-mass spectrometry (LC-MS).
The extract of Caesalpinia spinosa was tested for its antimicrobial effect against some common microorganisms and for growth promoting properties with respect to probiotic Lactobacillus plantarum strain.
The results of this research indicate that extracts from the plants studied may be suitable for use as natural food additives.<br>Los compuestos fenólicos de las plantas son, cada vez más, un tema de intensa investigación, debido a sus propiedades bioactivas como antioxidante, antimicrobiana, anti-mutagénico, anti-viral e incluso actividad anti-inflamatoria. El objetivo de este trabajo es determinar la actividad antioxidante de los extractos de plantas seleccionadas, como Caesalpinia spinosa, Perilla frutescens, Artemisia annua y Viola wittrockiana Gams. Se optimizó el método de extracción a través de combinaciones de disolventes orgánicos con agua. Todos extractos obtenidos se estudiaron por métodos in vitro: contenido de polifelones totales o determinación de la actividad antioxidante frente a radicales libres como el radical catiónico ABTS, el radical APPH y el comportamiento frente al catión Fe (II) (FRAP). Estos métodos, que dan una idea inicial del comportamiento del extracto y de los compuestos que hay en él, no siempre se correlacionan con la capacidad de inhibir el deterioro oxidativo de los lípidos en los alimentos, debido a que los ensayos in vitro no tienen en cuenta factores como la ubicación física del antioxidante, su interacción con la matriz del alimento o las condiciones ambientales. Por ese motivo, se han desarrollado modelos que permiten reproducir las condiciones esperadas en los productos alimenticios y evaluar con precisión el potencial antioxidante protector de la degradación de los lípidos en los alimentos. En esta línea se han analizado dos sistemas: uno llamado "sistema modelo" emulsión de aceite (exento de sus antioxidantes naturales) en agua y un sistema cárnico. Además, se analizó la composición química de cada uno de los extractos usando técnicas tales como cromatografía líquida de alta resolución (HPLC) o espectrometría de cromatografía-masa líquida (LC-MS). En el extracto de Caesalpinia spinosa se evaluó su efecto antimicrobiano frente algunos microorganismos comunes y el mayor desarrollo de una cepa probiótica Lactobacillus plantarum. Los resultados de esta investigación indican que los extractos de las plantas estudiadas pueden ser adecuados para su uso como aditivos naturales en alimentos
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Nascimento, Fábio Fialho do 1983. "Análise estocástica linear de estruturas complexas usando meta-modelo modal." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265736.
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Orientador: José Maria Campos dos Santos<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica<br>Made available in DSpace on 2018-08-28T14:26:32Z (GMT). No. of bitstreams: 1
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Previous issue date: 2015<br>Resumo: Este trabalho tem como objetivo geral investigar abordagens para a análise de incerteza em problemas de dinâmica estrutural, de forma computacionalmente eficiente, no contexto industrial. Neste sentido, utilizou-se um metamodelo, baseado no método da superfície de resposta, para simplificar a etapa do cálculo dos modos e das frequências naturais na análise de resposta em frequência da estrutura. Para viabilizar a análise de grandes modelos, a solução de elementos finitos foi realizada pelo Nastran®. O MatLab® foi utilizado para manipular os autovalores e autovetores, e calcular as FRFs. Já o processo de amostragem das variáveis, a preparação da superfície de resposta e a integração com os demais aplicativos, foram realizados por meio do Isight®. Inicialmente, a abordagem foi avaliada em um modelo simples de um para-brisa veicular, com espessura, modo de elasticidade e densidade como parâmetros incertos. Posteriormente, o método foi aplicado para um modelo de uma estrutura veicular com milhares graus de liberdade. Neste caso, as variáveis aleatórias consideradas foram espessuras de vinte peças estampadas. Todas as variáveis foram consideradas com distribuição normal. Para quantificar a incerteza na resposta dinâmica, a simulação por Monte Carlo foi conduzida em conjunto com o metamodelo. A variabilidade das frequências naturais e da FRF é comparada com o resultado do Monte Carlo direto<br>Abstract: This work has as general objective to investigate approaches for uncertainty analysis in structural dynamics problems in a computational efficient manner in an industrial context. In this sense, we used a metamodel based on the response surface method to simplify the process of modes and natural frequencies calculation for frequency response analysis of a structure. In order to make the process feasible for large models, the finite element solution was performed using Nastran®. MatLab® was used to manipulate the eigenvalues and eigenvectors and calculate the FRFs. Isight® was responsible for the variable sampling process, response surface preparation and integrating other applications as well. Initially, the approach was assessed in a simple model of a car windshield with its thickness, Young¿s modulus and material density as uncertain parameters. Later the method was applied to a vehicle structure model with thousands degrees of freedom. In this case, the random variables considered were thicknesses of twenty stamped parts. Gaussian distribution was considered for all variables. For the purpose of uncertainty quantification in the dynamic response, Monte Carlo simulation was performed over the metamodel. The variability of the natural frequencies and FRF is compared against to direct Monte Carlo results<br>Mestrado<br>Mecanica dos Sólidos e Projeto Mecanico<br>Mestre em Engenharia Mecânica
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Chu, Kai-cheung, and 朱啟祥. "The effects of mean reversion on dynamic corporate finance and asset pricing." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B47752762.
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This thesis aims to investigate the effects of mean reversion on dynamic corporate finance decisions and stock pricing.
In Chapter 1, a continuous-time real option model of mature firm that produces product with exogenous mean reverting price is developed to study the firm’s optimal exit and leverage policies. Simulation results show that both liquidation and bankruptcy triggers are negatively related to the long run price levels, while the speed of mean reversion interacts with the long run price level to affect the firm’s exit decisions in two opposite directions depending on the level’s relative magnitude to total operating expenses (the firm’s instantaneous operation costs plus coupon payments). Regarding the leverage policy, apart from showing the static tradeoff result that firm uses more debts when the current revenues are high, the model exhibits at high long run price levels low-debt scenarios that are analogous to the pecking order prediction, suggesting that both static tradeoff and pecking order effects coexist under a mean reversion environment. Because equity values increase more vigorously with prices than debt values do, the tradeoff effect is overwhelmed and the resulting optimal leverage ratios are generally decreasing with the current price levels.
Chapter 2 extends the model in Chapter 1 to derive the closed-form expression of the firm’s equity beta. Because expected stock returns are linearly related to the equity beta by model assumption, several implications to the cross-sectional behaviors of stock returns are obtained. First, it is predicted that firms with mean reverting characteristics should earn lower average returns than others without. The model further reveals the coexistence of positive book-to-market and leverage premiums to stock returns. Most importantly, due to the possession of bankruptcy option by equity holders, high distress risk stocks are expected to earn lower average returns than otherwise similar but low distress risk stocks. This provides an extra dimension to study the ‘distress premium puzzle’. Finally to verify the model predictions, empirical tests using historical market and accounting data from CRSP and COMPUSTAT are conducted, and supportive results are generally obtained.<br>published_or_final_version<br>Economics and Finance<br>Doctoral<br>Doctor of Philosophy
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Hauksson, Hilmar. "Metamodeling for Business Model Design : Facilitating development and communication of Business Model Canvas (BMC) models with an OMG standards-based metamodel." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-138139.
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Interest for business models and business modeling has increased rapidly since the mid-1990‘s and there are numerous approaches used to create business models. The business model concept has many definitions which can lead to confusion and slower progress in the research and development of business models. A business model ontology (BMO) was created in 2004 where the business model concept was conceptualized based on an analysis of existing literature. A few years later the Business Model Canvas (BMC) was published; a popular business modeling approach providing a high-level, semi-formal approach to create and communicate business models. While this approach is easy to use, the informality and high-level approach can cause ambiguity and it has limited computer-aided support available. In order to propose a solution to address this problem and facilitate the development and communication of Business Model Canvas models, two artifacts are created, demonstrated and evaluated; a structured metamodel for the Business Model Canvas and its implementation in an OMG standards-based modeling tool to provide tool support for BMC modeling.This research is carried out following the design science approach where the artifacts are created to better understand and improve the identified problem. The problem and its background are explicated and the planned artifacts and requirements are outlined. The design and development of the artifacts are detailed and the resulting BMC metamodel is presented as a class diagram in Unified Modeling Language (UML) and implemented to provide tool support for BMC modeling. A demonstration with a business model and an evaluation is performed with expert interviews and informed arguments.The creation of a BMC metamodel exposed some ambiguity in the definition and use of the Business Model Canvas and the importance of graphical presentation and flexibility in the tools used.The evaluation of the resulting artifacts suggests that the artifacts do facilitate the development and communication of the Business Model Canvas models by improving the encapsulation and communication of information in a standardized way and thereby the goals of the research are met.
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Lilienthal, Friederike, P. Sácha, and Christoph Jacobi. "Gravity wave effects on a modeled mean circulation." Universität Leipzig, 2015. https://ul.qucosa.de/id/qucosa%3A16646.
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Using a global circulation model of the middle atmosphere we analyze the influence of different tropospheric gravity wave amplitude distributions in the gravity wave parameterization on the mean circulation. Thereby we compare the standard configuration, which includes a simple zonal mean weighting of gravity wave amplitudes with a more realistic zonal mean weighting obtained from measurements using GPS radio occultations and a GW distribution in both latitude and longitude. The results show a stronger polar vortex and a descent of the meridional wind jet in the mesopause. Furthermore, two-dimensional weightings from the measurements are considered in order to analyze nonzonal effects resulting especially in stationary planetary waves. In this case we obtain a stronger stationary planetary wave and find enhanced equatorward wave motions in the lower stratosphere. These results give reason for further investigations about the impact of gravity waves on the Brewer-Dobson circulation.<br>Mit Hilfe eines globalen Zirkulationsmodells für die mittlere Atmosphäre untersuchen wir den Einfluss verschiedener in der Troposphäre festgelegter Verteilungen der Schwerewellenamplitude in der Schwerewellenparametrisierung des Modells auf die mittlere Zirkulation. Dazu vergleichen wir den Standardfall zonal gemittelter künstlicher Wichtungen der Schwerewellenamplituden mit sowohl zonal gemittelten als auch längen-breitenabhängigen Wichtungen aus GPS-Radiookkultationensmessungen. Die Ergebnisse zeigen einen stärkeren Polarwirbel und ein Absinken des meridionalen Windjets in der Mesopause. Zusätzlich wurden zweidimensionale Wichtungen aus den GPS-Radiookkultationen ausgwertet, um den Einfluss planetarer Wellen zu analysieren. In diesem Fall lässt sich eine äquatorwärts gerichtete Verstärkung der Wellenbewegung in der unteren Stratosphäre feststellen. Diese Ergebnisse geben Anlass für weitere Nachforschungen über den Einfluss von Schwerewellen auf die Brewer-Dobson-Zirkulation.
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Rasiwasia, Akshay. "Meta Modeling for Business Model Design : Designing a Meta model for E3 value model based on MOF." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119800.
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E3 value model is a conceptual tool to express the business logic of a firm from a holistic perspective, focusing on the value proposition that the firm offers and the architecture of its network of partners. It can be used as a tool of alignment between the business strategy and business process. However, the lack of concrete modeling principles and relationship between the components of a business makes extraction of knowledge difficult from e3 value models. It remains isolated from the rest of the business design and IS architecture. Software architects face difficulty in extracting knowledge from business models to design information systems. On the other hand, business analysts find hardship in communicating and controlling system design changes as the business model changes over time. To solve these problems, the thesis proposes the design and implementation of a well-defined e3 value meta-model such that the e3 models then created are compatible with UML and could be serialized as XML. The meta-model designed clearly defines the relationship between each e3 value model components and also adds a classification of value objects as an extension to the meta-model. To illustrate the usefulness of this meta-model, and its inherent validation properties to create a correct e3 value model, a graphical editor tool for end user is created. A case study is then conducted at a software company, and its business model is then implemented to demonstrate the efficiency of both the meta-model and the tool. The research work closely follows the design science guidelines and principles to achieve the results.
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Samant, Nikhil. "Frontend for cyrano meta model." Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-04122010-083457/.
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Kövamees, Gustav. "Particle-based Stochastic Volatility in Mean model." Thesis, KTH, Matematisk statistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-257505.
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This thesis present a Stochastic Volatility in Mean (SVM) model which is estimated using sequential Monte Carlo methods. The SVM model was first introduced by Koopman and provides an opportunity to study the intertemporal relationship between stock returns and their volatility through inclusion of volatility itself as an explanatory variable in the mean-equation. Using sequential Monte Carlo methods allows us to consider a non-linear estimation procedure at cost of introducing extra computational complexity. The recently developed PaRIS-algorithm, introduced by Olsson and Westerborn, drastically decrease the computational complexity of smoothing relative to previous algorithms and allows for efficient estimation of parameters. The main purpose of this thesis is to investigate the volatility feedback effect, i.e. the relation between expected return and unexpected volatility in an empirical study. The results shows that unanticipated shocks to the return process do not explain expected returns.<br>Detta examensarbete presenterar en stokastisk volatilitets medelvärdes (SVM) modell som estimeras genom sekventiella Monte Carlo metoder. SVM-modellen introducerades av Koopman och ger en möjlighet att studera den samtida relationen mellan aktiers avkastning och deras volatilitet genom att inkludera volatilitet som en förklarande variabel i medelvärdes-ekvationen. Sekventiella Monte Carlo metoder tillåter oss att använda icke-linjära estimerings procedurer till en kostnad av extra beräkningskomplexitet. Den nyligen utvecklad PaRIS-algoritmen, introducerad av Olsson och Westerborn, minskar drastiskt beräkningskomplexiteten jämfört med tidigare algoritmer och tillåter en effektiv uppskattning av parametrar. Huvudsyftet med detta arbete är att undersöka volatilitets-återkopplings-teorin d.v.s. relationen mellan förväntad avkastning och oväntad volatilitet i en empirisk studie. Resultatet visar på att oväntade chockar i avkastningsprocessen inte har förklarande förmåga över förväntad avkastning.
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Martorello, Cristiane Dias de Souza. "Epidemiology in complex networks - modified heterogeneous mean-field model." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/100/100132/tde-16012019-173906/.
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The study of complex networks presented a huge development in last decades. In this dissertation we want to analyze the epidemic spread in scale-free networks through the Susceptible - Infected - Susceptible (SIS) model. We review the fundamental concepts to describe complex networks and the classical epidemiological models. We implement an algorithm that produces a scale-free network and explore the Quenched Mean-Field (QMF) dynamics in a scale-free network. Moreover, we simulate a change on the topology of the network according to the states of the nodes, and it generates a positive epidemic threshold. We show analytically that the fraction of infected vertices follows a power-law distribution in the vicinity of this critical point<br>O estudo de redes complexas tem se desenvolvido muito nos últimos anos. Nesta dissertação queremos analisar o processo de propagação de epidemia em redes livres de escala através do modelo Suscetível - Infectado - Suscetível (SIS). Apresentamos uma revisão de redes e as principais características dos modelos epidemiológicos clássicos. Implementamos um algoritmo que produz uma rede livre de escala dado um expoente e exploramos a dinâmica do modelo Quenched Mean-Field (QMF) inserido em uma rede livre de escala. Além disso, foi simulada uma possível alteração na topologia da rede, devido aos estados dos vértices infectados, que gerou um limiar epidêmico positivo no modelo e a probabilidade de vértices infectados seguiu uma lei de potência na vizinhança desse ponto crítico
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Dansereau, Véronique. "Ice shelf-ocean interactions in a general circulation model : melt-rate modulation due to mean flow and tidal currents." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78549.
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Thesis (S.M.)--Joint Program in Physical Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2012.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 121-123).<br>Interactions between the ocean circulation in sub-ice shelf cavities and the overlying ice shelf have received considerable attention in the context of observed changes in flow speeds of marine ice sheets around Antarctica. Modeling these interactions requires parameterizing the turbulent boundary layer processes to infer melt rates from the oceanic state at the ice-ocean interface. Here we explore two such parameterizations in the context of the MIT ocean general circulation model coupled to the z-coordinates ice shelf cavity model of Losch (2008). We investigate both idealized ice shelf cavity geometries as well as a realistic cavity under Pine Island Ice Shelf (PIIS), West Antarctica. Our starting point is a three-equation melt rate parameterization implemented by Losch (2008), which is based on the work of Hellmer and Olbers (1989). In this form, the transfer coefficients for calculating heat and freshwater fluxes are independent of frictional turbulence induced by the proximity of the moving ocean to the fixed ice interface. More recently, Holland and Jenkins (1999) have proposed a parameterization in which the transfer coefficients do depend on the ocean-induced turbulence and are directly coupled to the speed of currents in the ocean mixed layer underneath the ice shelf through a quadratic drag formulation and a bulk drag coefficient. The melt rate parameterization in the MITgcm is augmented to account for this velocity dependence. First, the effect of the augmented formulation is investigated in terms of its impact on melt rates as well as on its feedback on the wider sub-ice shelf circulation. We find that, over a wide range of drag coefficients, velocity-dependent melt rates are more strongly constrained by the distribution of mixed layer currents than by the temperature gradient between the shelf base and underlying ocean, as opposed to velocity-independent melt rates. This leads to large differences in melt rate patterns under PIIS when including versus not including the velocity dependence. In a second time, the modulating effects of tidal currents on melting at the base of PIIS are examined. We find that the temporal variability of velocity-dependent melt rates under tidal forcing is greater than that of velocity-independent melt rates. Our experiments suggest that because tidal currents under PIIS are weak and buoyancy fluxes are strong, tidal mixing is negligible and tidal rectification is restricted to very steep bathymetric features, such as the ice shelf front. Nonetheless, strong tidally-rectified currents at the ice shelf front significantly increase ablation rates there when the formulation of the transfer coefficients includes the velocity dependence. The enhanced melting then feedbacks positively on the rectified currents, which are susceptible to insulate the cavity interior from changes in open ocean conditions.<br>by Véronique Dansereau.<br>S.M.
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Doi, Fabrício. "Objetos adaptativos: aplicação da tecnologia adaptativa à orientação a objetos." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3141/tde-09012008-095135/.
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Este trabalho estuda o problema da construção de sistemas orientados a objetos com características adaptativas, tendo como principal objetivo simplificar o processo de construção. Para isso o trabalho utiliza como base teórica a Tecnologia Adaptativa e sua aplicação em diversos formalismos. O Modelo Adaptativo de Objetos foi utilizado como base de comparação de soluções para a construção de sistemas adaptativos. Nesta pesquisa são apresentadas aplicações e uma proposição para a construção e modelagem de sistemas adaptativos, através da extensão do conceito de objetos com características da tecnologia adaptativa. Através deste estudo avaliou-se o impacto da aplicação do dispositivo adaptativo em um formalismo com tipo. Os resultados obtidos no presente trabalho demonstram que a tecnologia adaptativa é propícia para linguagens orientadas a objetos e que os diagramas UML são capazes, com pequenas extensões, de representar o comportamento adaptativo adequadamente.<br>This study addresses the issue of implementing object-oriented software with adaptive characteristics, having as primary purpose simplify the implementing process. The key theoretical basis consisted in adaptive technology and its application in various formalisms. Adaptive Object Model has been taken as comparison basis to solutions to implement adaptive systems. This study describes applications and a proposition to implement and model adaptive systems, through the extension of object concept with adaptive technology characteristics. It also evaluates the impact of applying adaptive devices in formalism with types. The results obtained demonstrate that adaptive technology is suitable for object-oriented languages and that UML diagrams are capable of presenting adaptive behavior appropriately with a small number of extensions.
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Thompson, Russell Martin. "Nitrosylmetalloporphyrin complexes as models for cured meat pigments." Thesis, University of Surrey, 1988. http://epubs.surrey.ac.uk/848117/.
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A range of nitrosylmetalloporphyrin complexes, M(porph)NO [M = Fe, Co; porph = TPP, OEP, T[PIV]PP], some labelled with [15]NO, has been synthesised and investigated as structural and spectroscopic models of the cured meat pigment, nitrosylmyoglobin. The nitrosylmetalloporphyrins were found to be unstable in solution (and some in the solid state) with respect to loss or further reaction of the nitrosyl ligand. The diamagnetic cobalt (III) porphyrin nitrosyIs and a range of other square pyramidal complexes of cobalt(III) with an apical nitrosyl ligand have been further investigated by [15]N and [59]Co NMR spectroscopy to establish whether the CoNO group is bent or linear and to study nephelauxetic and spectrochemical effects at the metal. In all cases studied the CoNO group is bent (CoNO ~ 120°). The basal ligands were dithiocarbamate, tetradentate Schiff base, porphyrin, and bidentate diamine and oximate giving S[4], S[2]N[2], N[4], OONN, or ONON coordination in the equatorial plane. The shielding of both cobalt and nitrogen tends to decrease with decrease in M(d) to pi* (NO) back-bonding as indicated by M-N and N-O bond distances, and the MNO angle and the NO stretching frequencies. The shieldings decrease with electron withdrawal by ring substituents and also in going from sulphur to nitrogen to oxygen coligands, i.e. with decrease in ligand field splitting and in the nephelauxetism of the coligands. The bent nitrosyls of cobalt can function as oxygen transfer catalysts via a nitrosyl-nitro couple. Consequently, a range of Co(III) porphyrin nitro complexes, (L)Co(porph)NO[2] (porph = TPP, OEP; L = py, 1Melm) and several nitro complexes containing the other basal ligands have been synthesised and investigated by the [15]N and [59]Co NMR technique. The coordinated nitro ligand is labile and linkage isomerism and ligand exchange have been observed. These observations may be related to the deterioration of cured meat colour which is of importance to the food industry. The crystal structure of (py)Co(TPP)NO[2] is presented; the nitro group of which is rotationally disordered. Recrystallisation of (1MeIm)Co-(TPP)NO[2] gave [Co(TPP)(1Melm)[2]]NO[2], the crystal structure of which has been determined. Formation of this nitrite is further evidence for the lability of the nitro ligand. The known complex Fe(salphen)NO was prepared using ascorbic acid for the first time to prevent contamination with the oxo-bridged iron(III) dimer. Variable temperature [57]Fe Mossbauer effect studies of the S = 1/2 to S = 3/2 spin transition for Fe(salphen)NO show that the crossover is continuous and centred at T[c] ~ 181 K, and that the electronic transition between the two spin states is rapid on the Mossbauer timescale. The fluxionality of CoCl[2]([15]NO)(PPh[2]Me)[2] was studied by variable temperature [15]N and [31]P NMR. An [17]O NMR study of the ?-peroxo complex [(NH[3])[5]Co[17]O[2]Co(NH[3])[5]](NO[3])[4]. 2H[2]O is presented. An attempt to measure [15]N NMR spectra of the diamagnetic 18 electron species, Fe(porph)([14]NO)([15]NO) (porph = TPP, OEP) presumably containing linear FeNO[+] and bent FeNO[-] was unsuccessful.
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Jaile, Benítez Josep Maria. "Model de predicció de la cotització del preu del porcí, basat en la teoria dels expertons i en xarxes neuronals." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/277094.
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The meat industry is the most important economic activity in the agrofood sector, which (in Spain) is 20.6%. The meat industry contributes to the 1.7% Spanish GDP, billing 16 billion Euros (2006), employing more than 85,000 people, persisting numbers (2012) despite the economic crisis. The pork is the most consumed meat worldwide, in Europe and in Spain, where it represents 58% of the meat consumed (2005). This thesis has the preliminary objective to study the forces that shape (constitute) the price of pork. The final goal is to design a Model that helps us to predict that price with the help of artificial neural networks<br>El sector carni constitueix l’activitat econòmica més important dins el sector agroalimentari, del que (a Espanya) representa el 20,6%. El sector carni aporta l’1,7% al PIB espanyol, facturant 16 mil milions d’euros (2006), donant ocupació a més de 85.000 persones, xifres que actualment (2012) perduren malgrat la crisi econòmica. La carn de porcí és la més consumida arreu del món, també a Europa com a Espanya, on representa el 58% de la carn consumida (2005). Aquesta tesi té com a objectiu preliminar, estudiar les forces que influeixen significativament en la cotització del preu del porcí. L’objectiu final és el de dissenyar un Model que ens ajudi a la predicció d’aquest preu amb l’ajuda de les xarxes neuronals artificials
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Ahmed, Adnan, and Syed Shahram Hussain. "Meta-Model of Resilient information System." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5130.
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The role of information systems has become very important in today’s world. It is not only the business organizations who use information systems but the governments also posses’ very critical information systems. The need is to make information systems available at all times under any situation. Information systems must have the capabilities to resist against the dangers to its services,performance & existence, and recover to its normal working state with the available resources in catastrophic situations. The information systems with such a capability can be called resilient information systems. This thesis is written to define resilient information systems, suggest its meta-model and to explain how existing technologies can be utilized for the development of resilient information system.
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Tada, Yuri. "Descriptive meta-model of decision making /." The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488202678775585.
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Ko, Hung-Tse. "Distribution system meta-models in an electronic commerce environment." Ohio : Ohio University, 2001. http://www.ohiolink.edu/etd/view.cgi?ohiou1173977323.
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Braunwart, Paul R. "Uncovering and avoiding failure modes in driveline and tire/wheel NVH using a computational meta-model." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/43099.
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Thesis (S.M.)--Massachusetts Institute of Technology, System Design and Management Program, 2007.<br>Includes bibliographical references (p. 105-110).<br>The automotive industry has undergone significant changes in recent years with increased competition and the introduction of new manufacturers into the market. With this changing market, a more efficient approach to Noise Vibration and Harshness (NVH) development is needed to foster better decisions and support the compressed product development timing required by the market.To address this, the "Slider Bar" process and meta-model are presented. Based on the failure mode avoidance approach, the process and model allow the engineering teams to uncover and avoid potential tire/wheel and driveline NVH failure modes. Therefore, early in the product development process, development teams can identify control and noise factor limits and system level effects, avoid potential NVH failure modes, and develop appropriate countermeasures.Using insights from innovation diffusion theory, the process and tool were deployed systematically to NVH community, with user insights used to adapt and improve the process and tools. Based on this work, a strategy is introduced for the development and adoption of a failure mode avoidance initiative.<br>by Paul R. Braunwart.<br>S.M.
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Chua, Kel Win. "Predictive model of fluidized bed melt granulation." Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505425.
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This thesis describes the development of a computer model that predicts aggregation behavior in fluidized bed melt granulation (FBMG) processes. In FBMG processes, the molten binder enters at one or more points and is then distributed around the bed, these processes are necessarily spatially inhomogeneous. Current granulation modelling using Population Balance Equations (PBE) adopts a lumped approach, using a single lumped rate constant. This thesis shows how to take account of these spatially distributed processes and then predicted the apparent lumped rate constant. The first half of this thesis presents a series of experimentally validated sub-models to describe time scales of events leading to aggregation. These events are granule-granule collision, droplet-granule collision, binder spreading and binder solidification. Computational Fluid Dynamic using a twin-fluid model is used to calculate granulegranule collision time scale and droplet-granule collision time scales. A Volume of Fluid method is used to calculate binder spreading time scales. A dynamic energy balance is used to calculate binder solidification time scales. Validation of the twin-fluid model is done by comparing fluidized bed pressure time series with experiment. Validation of spreading model is done using high speed images of binder droplet spreading. Validation of solidification model is done using high speed infrared images of binder droplet solidification on glass plate. Generalizations for binder spreading time scale and binder solidification time scale are made, so that these time scales for other FBMG process can be calculated directly, reducing the reliance on computational modelling. Granule-granule collision time scale per particle is in the region of O.Ols. Binder spreading time scale is less than O.OOls~ Binder solidification time scale varies from 0.005s to O.Ols. This wider variation for solidification time scale is caused by the effect of fluidized bed operating temperature. By separation of time scales, we evaluate probability that a granule is wet upon granulegranule collision. Binder contact angle determines the wetted area covered by single droplet. Droplet solidification time scale determines the lifetime of the wetted area. This probability is used to calculate granulation efficiency. Applying granulation efficiency with collision rates allows aggregation rate constants for different process variables in FBMG to be evaluated. Our evaluation found that most aggregation takes place within 5cm of the nozzle. In general the calculated aggregation rate constant is higher than the experimentally measured aggregation rate constant. \Ve attributed the unknown effects of averaging across granule SIze, the probability of liquid bridge survival and probability of solid bridge survival with an apparent probability of survival.