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Moradiannejad, Hesam. "Controlling texture in processed meat production". Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/48111/.
Testo completoAbstract (sommario):
The present study showed the effects of a number of hydrocolloids in terms of adding them dry, pre-hydrated or solubilised and gelled, using unmodified wheat starch, 3 types of carrageenan (kappa, iota and lambda), locust bean gum (LBG), and finally citrus fibre on meat stability, textural properties, and microstructure. The study further elucidated the role of heat induced gelation in texture formation of processed meat products. The finding of the study revealed that the maximum hardness related to the dry state of all hydrocolloids when added to a product containing 65% meat (i.e. 7.4% unmodified wheat starch, 1% LBG and 3% citrus fibre, except the carrageenan treatment, which is related to 2% gelled kappa carrageenan). Furthermore, the elasticity or rubbery texture of the sausages increased with 3% pre-hydrated wheat starch, 1 % dry LBG and citrus fibre and finally 1% solubilised kappa carrageenan with 65% meat. However, ameliorating elasticity of LBG and citrus fibre, which are 1 and 3%, respectively, took place with the dry state. The Differential Scanning Calorimetry (DSC) results showed that starch and carrageenan showed clear irreversible and reversible transitions, respectively, on the timescale of the experiment in the region of 60 ̊C, whereas locust bean gum and citrus fibre showed no transitions. No interaction between carbohydrates and proteins was signalled by the transition temperatures of the unaffected transitions and the addition of enthalpies which was linear. The rheology result indicated that storage modulus (G ́) was greater than the loss modulus (G ̋) during the test (G ́ > G ̋), which implied predominant elastic behaviour of the sample for the whole range of deformation experimented. Finally, confocal scanning laser microscopy (CSLM) demonstrated that the void space is augmented (visa-a-vis the control sample of 65% meat) after adding dry LBG. However, the size of cavity shrank after adding gelled kappa carrageenan, dry citrus fibre, and dry wheat starch. In all treatments, the fat droplet decreased in mean size in the wake of adding hydrocolloids in the systems. Both of these findings indicate that an increase in batter texture upon the addition of hydrocolloids was sufficient to break up air cells and emulsion droplet, and then had enough strength to maintain the smaller cells droplets. The findings of the study in hand, provide a new approach to meat product manufacturing.
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Hullberg, Anja. "Quality of processed pork : influence of RN genotype and processing conditions /". Uppsala : Dept. of Food Science, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a438.pdf.
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Mixon, Bobby J. "Competitiveness of U.S. processed meat industries in the Pacific Rim". online access from Digital dissertation consortium access full-text, 1996. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?9632953.
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Sindelar, Jeffrey Joseph. "Investigating uncured no nitrate or nitrite added processed meat products". [Ames, Iowa : Iowa State University], 2006.
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Tlhong, Tumelo Maud. "Meat quality of raw and processed guinea fowl (Numeda meleagris)". Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/1898.
Testo completoAbstract (sommario):
Thesis (MSc (Consumer Science)--Stellenbosch University, 2008.The purpose of this study was to investigate the chemical composition mineral and cholesterol content of the different cuts (breast, drumstick and thigh) of raw guinea fowl meat. The study also aimed at establishing the effect of cooking method on guinea fowl quality attributes by investigating the effect of different cooking methods on the chemical composition and sensory attributes of the different cuts. The effect of injecting a brine solution on the chemical composition and sensory attributes were also investigated. There were no differences in terms of moisture content of the various cuts raw guinea fowl meat The breast had significantly higher protein content when compared to drumstick and thigh (P<0.05). The fat content was similar for all the cuts (P>0.05). Whilst the drumstick had significantly the lowest value for ash content when compared to the thigh. Saturated fatty acids (SFAs) and total unsaturated fatty acids (TUFAs) were not different (P>0.05) in all the cuts. Drumstick had significantly higher monounsaturated fatty acids compared to other cuts (P<0.05), and it had the highest polyunsaturated fatty acids (P<0.05). The breast had the lowest (P<0.05) n-6 fatty acid value (44.25) and had relatively the lowest Polyunsaturated:Saturated (P:S) fatty acid ratio of 1.74 when compared to the other cuts. High n-6:n-3 ratios, ranging from 7.05 to 16.58, were also found in all the cuts. Cholesterol was lowest (P<0.05) in the breast. Seventeen amino acids were found, including the eight of the nine essential amino acids. Significant differences were found in amino acid values for the different cuts. Values of iron were significantly higher in the drumstick and thigh cuts (P<0.05), whilst drumstick had the highest zinc content of all the cuts (P<0.05). On investigating the effect of three cooking methods (baking-bag, foil-wrap, open-roasting at 140ºC for 65 minutes) on the chemical composition, the open-roasting method produced higher moisture content (P<0.05) consistently for all cuts, with the breast having the highest and the drumstick the lowest (P<0.05). The moisture content of the baking-bag method on the other hand was consistently the lowest (P>0.05). This effect was significant for the breast, which had lost the most moisture (P<0.05). The baking-bag method consistently resulted in a higher protein content, which is attributed to the higher moisture loss (P<0.05) in comparison with the other methods, resulting in a more concentrated product. With regard to the fat content no effect resulting from the cooking methods could be observed (P>0.05), but the cuts’ natural fat content was reflected especially in the open–roasting method (P<0.05) giving further support to the understanding that the open-roasting method indeed made the least inroads on the chemical composition of guinea fowl meat under these restraints: controlled for cooking time and temperature, internal temperature not controlled. All the cuts cooked according to all the methods, had the favourable >0.4 Polyunsaturated:Saturated fatty acids (P:S) ratio, ranging from 0.91 to 1.42 between cuts and treatments. The n-6:n-3 ratio was below the recommended beneficial value, namely <4:1, in all the cuts irrespective of all the cooking methods, ranging from 2.47 to 3.08. The study of the effect of the three cooking methods (baking-bag, foil-wrap and open-roast) on the sensory attributes of the breast meat revealed that aroma-intensity of the three cooking treatments did not differ significantly (P>0.05). Foil-wrap produced a more tender and juicier product (P<0.05), while, when using the baking-bag method, values for flavour decreased (P<0.05). It is proposed that a higher internal temperature (which was not controlled) was attained when using the baking-bag method (temperature and time controlled) resulting in loss of volatile flavour components. The effect of the three cooking methods (baking-bag, foil-wrap and open-roast) on the proximate composition (moisture, protein, fat and ash) of raw and cooked breast meat was investigated. As anticipated raw breast meat had higher moisture content (74.55%, P<0.05) than the cooked cuts, with open-roasting showing the highest (68.55%) value and foil-wrap close second (68.12%). These values differed significantly from the baking-bag method (66.06%, P<0.05). An investigation on the effect of brine infusion on the sensory attributes and chemical composition (proximate and fatty acid composition, and mineral content) of breast meat, baked in foil-wrap, was carried out using descriptive sensory analysis with the injected breast and the control as variable. There were no significant differences (P>0.05) between the injected and the control samples for any of the sensory attributes of aroma, tenderness, initial juiciness, sustained juiciness and flavour. Judge:treatment variations were observed for all the attributes, and samples differed for all attributes except for aroma. It is proposed that the use of the hand injector could not effectively distribute the brine solution, hence the recommendation to repeat the experiment using an electronic multineedle-injector. No effect was observed for the proximate composition (P>0.05). Further research pertaining to cooking methods of meat of free-range guinea fowl is recommended to address certain issues that have been highlighted.
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Weber, Lauren Allison. "Determining the yield and chemical characteristics of trimmings from hot processed and traditionally processed cull meat goats". Thesis, Kansas State University, 2010. http://hdl.handle.net/2097/7134.
Testo completoAbstract (sommario):
Master of ScienceDepartment of Animal Sciences and Industry
Terry A. Houser
Two experiments were completed as a part of this study. The objective of the first experiment was to determine the differences in chemical characteristics of trimmings from hot processed and traditionally processed cull meat goats. Crossbred cull doe goats (n=18) were assigned to one of 3 kills days with 6 replications per day. The sides of each goat were randomly assigned to hot processed (HP) or traditionally processed (TP). HP sides were fabricated within 2 h of slaughter, ground with 2% salt and dry ice and then held at 2oC for 24h. TP sides were chilled at 2oC for 24 h prior to fabrication and grinding. After sampling, 2% salt was added to remaining trim yielding 2 treatments: traditionally processed with no salt added (TPNS) and traditionally processed with salt added (TPS). As expected, the HP treatment had a higher (P<0.0001) ultimate pH than TP and a higher water holding capacity (WHC) than TPS (P<0.002) and TPNS (P<0.001) treatments. HP and TPNS had significantly higher (P<0.0007 and P<0.0003, respectively) percent moisture than TPS. Percent fat was similar (P>0.19) for all treatments. However, TPNS had more protein (P<0.0001) than either the HP or TPS treatments. HP and TPS had decreasing L* values until d 6 when values increased significantly while TPNS decreased steadily by day. HP and TPS differed significantly from TPNS until d 6 when no significant differences were seen. For all treatments, a* values showed decreasing values until d 6. For all treatments, b* values increased until d 5. The objective of the second experiment was to investigate the viability of composting as a means for disposing of goat tissues resulting from the slaughter and fabrication process. By-products from the slaughter of cull meat goats (n=18) were assigned to 3 treatment piles: bones, offal + head (OH), and whole (bones, skull, and offal). Bones and OH piles increased in temperature, with peaks at wk 7 and wk 9, while whole piles had elevated temperatures from wk 5 to wk 9. Bone piles had statistically lower temperatures through wk 3, but were not statistically different than other treatments through the duration of the study. Whole piles had higher (P<0.0001) temperatures over the 8 wk composting period than OH and bone piles. Bone decomposition progressed over 90 d; at d 60, bones in whole piles had greater (P<0.05) decomposition than in bone piles. Similarly, skulls decomposition increased over the 90 d period. At d 60 and 90, skulls in whole piles had greater (P<0.05) decomposition than skulls in OH piles.
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Katsande, T. C., e R. Govender. "A microbiological survey of fresh meat processed at abattoirs in Gauteng, South Africa". Journal for New Generation Sciences, Vol 12, Issue 2: Central University of Technology, Free State, Bloemfontein, 2014. http://hdl.handle.net/11462/659.
Testo completoAbstract (sommario):
Published ArticleThe abattoir Hygiene Management System (HMS) was regulated in South Africa under the Meat Safety Act 40 of 2000. Presently, there is no national regulated microbiological standard to compare against meat tested at abattoirs as an indicator of good hygiene practices. The aim of the study was to establish a provincial guideline for a microbiological baseline. This may be used to verify the performance of the implemented HMS. Thirty red meat and twenty-two poultry abattoirs were sampled to determine baseline Total Bacterial Counts (TBCs). The results of this study were compared to standards presently used in the United Kingdom (UK). The results compared favourably.
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Koep, Karin Sarah Coles. "Production of salami from meat of aquatic and terrestrial mammals". Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1073.
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Jackson, Armitra. "Investigating the microbiological safety of uncured no nitrate or nitrite added processed meat products". [Ames, Iowa : Iowa State University], 2010. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3403805.
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Smith, Marshall Dean. "A Product Development Study: Rainbow Trout Bologna". DigitalCommons@USU, 1999. https://digitalcommons.usu.edu/etd/5473.
Testo completoAbstract (sommario):
Mechanically deboned rainbow trout (Oncorhynchus mykiss) was analyzed and then used in texture studies. The meat contained a moderately low amount of fat (10% ± 2%, x ± SD). Pre-deboned meat had more calcium than deboned meat (PIF/=0.37). A combined response model predicted formulations for fish sausage that would closely duplicate the texture of commercially available processed meats. A thermal model was developed that helped verify the thermal properties of rainbow trout. Thermal conductivity was measured (k == 0.48 W/m·K) and specific heat was calculated (Cp= 3200 J/kg·K).
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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.
Testo completoAbstract (sommario):
Doctor of PhilosophyFood Science Institute
J. Scott Smith
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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Waldenby, Anna, e Karin Svanberg. "Hög köttkonsumtion och hur den kan påverka risken för folksjukdomar : en litteraturstudie baserad på kvinnor". Thesis, Högskolan i Skövde, Institutionen för vård och natur, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-5987.
Testo completoAbstract (sommario):
Bakgrund: Vi äter allt mer kött. Tidigare forskning har visat på samband mellan högt köttintag och bland annat hjärt- och kärlsjukdomar och cancer. Information om skyddsfaktorer som minskar risken för folksjukdom är begränsad. Forskning om hälsa och sjukdom hos kvinnor är begränsad och därför behövs kvinnors hälsa lyftas fram. Syfte: Litteraturstudiens syfte var att undersöka huruvida ett högt köttintag kan påverka risken för folksjukdomar hos kvinnor. Resultat: Resultatet tyder på en koppling mellan ett högt intag av rött och bearbetat kött och folksjukdomar hos kvinnor. Samband har funnits mellan högt köttintag och bröstcancer, diabetes och hjärt- och kärlsjukdomar. Riskerna har visat sig kunna minska vid ett utbyte från det röda och bearbetade köttet till andra animaliska proteinkällor eller vegetabilier. Diskussion: Kosten bör vara en viktig förebyggande insats när det gäller folksjukdomar. Kostråd för kvinnor bör innefatta ett lågt intag av rött och bearbetat kött och en kost rik på frukt, grönsaker och protein från andra källor än rött och bearbetat kött. Slutsats: Tydliga och enhetliga kostråd bör tas fram för att minska folksjukdomarna hos den kvinnliga befolkningen.Background:Our meat intake increases. Previous research has shown the connection between high meat intake, including cardiovascular disease and cancer. Information on appropriate diet to reduce the risk of endemic disease is limited. Research on health and disease in women is limited and, therefore, women's health must be taken seriously. Objective: The aim of the literature study was to investigate whether a high meat intake may influence risk of endemic diseases in women. Results: The results suggest a link between a high intake of red and processed meat and endemic diseases in women. Correlations have been found between high meat intake and breast cancer, diabetes and cardiovascular disease. Exchanges from the red and processed meat to other sources of animal protein and vegetables have been shown to reduce the risk of endemic diseases. Discussion: Advice on diet should be an important prevention strategy on endemic diseases. Advice on diet for women should include a low intake of red and processed meat and a diet rich in fruits, vegetables and protein from sources other than red and processed meat. Conclusion: Clear and consistent dietary guidelines should be developed to help reduce the endemic diseases of the female population.
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Hussain, Syeda Kauser Oyarzabal Omar A. "Effect of different atmospheres for isolation, molecular characterization, pathogenicity gene screening, and control of Campylobacter spp. from processed broiler meat". Auburn, Ala, 2009. http://hdl.handle.net/10415/1708.
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Cabral, Anderson Roberto. "Perfil lipídico de hambúrgueres produzidos a partir de carne de bovinos alimentados com fontes de óleo na dieta". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/74/74131/tde-18052016-140325/.
Testo completoAbstract (sommario):
Objetivou-se nesse trabalho avaliar os efeitos de fontes de óleo vegetal na dieta de bovinos Nelore em fase de terminação sobre a aceitação sensorial, teores de colesterol e óxidos de colesterol, composição de ácidos graxos e estabilidade oxidativa de hambúrgueres bovinos, avaliados após serem congelados e acondicionados a -18°C por 90 dias, então avaliados crus e grelhados. Foram confinados 96 bovinos, machos, castrados, Nelore, com aproximadamente 380 kg de peso inicial e idade média de 24 meses, alimentados com óleos de soja, girassol, linhaça e tratamento controle sem adição de óleo por 82 dias. A partir do músculo Longissimus e da gordura subcutânea dos animais foram produzidos hambúrgueres Os hambúrgueres produzidos com carne de bovinos que receberam óleo de soja tiveram maior estabilidade lipídica, tanto para zero quanto para 90 dias de armazenamento quando comparado às outras dietas. O método cru de preparo também resultou em menores valores tanto para o tempo zero quanto para o tempo 90 dias de armazenamento, em relação ao método grelhado. Os hambúrgueres dos animais alimentados com o óleo linhaça resultaram em menores valores para o atributo sabor. O tempo zero dias de armazenamento dos hambúrgueres resultou em maiores notas dos consumidores para a textura e aceitabilidade global, em relação às amostras armazenadas por 90 dias. A porcentagem de ácidos graxos polinsaturados foi reduzida, independente dos tratamentos, após 90 dias de armazenamento. O CLA c9 t11 foi encontrado em maiores quantidades nas amostras dos animais alimentados com os óleos de linhaça e soja, para zero e 90 dias de armazenamento. O teor de colesterol aumentou após as amostras de hambúrgueres serem grelhadas, enquanto que não foi observado efeito para as fontes de óleos e os tempos de armazenamento. Foi observada a presença de óxidos de colesterol após as amostras serem armazenadas por 90 dias, independente das fontes de óleos utilizadas. O fornecimento de óleos insaturados para bovinos confinados aumenta a porcentagem de ácidos graxos polinsaturados em hambúrgueres produzidos com carne e gordura desses. A inclusão de óleos vegetais para bovinos aumenta a oxidação lipídica de hambúrgueres produzidos a partir de carne e gordura provenientes desses animais quando comparados a um tratamento sem inclusão de óleos vegetais. Hambúrgueres produzidos com carne e gordura de animais alimentados com óleos vegetais na dieta possuem maior oxidação lipídica após 90 dias de armazenamento quando comparados com os hambúrgueres do tempo zero e dos hambúrgueres do tratamento controle enquanto que o processamento térmico não foi responsável pela maior oxidação lipídica.The aim of this study was to evaluate the effects of vegetable oil sources in Nellore diet in the finishing phase of the sensory analysis, cholesterol analysis and cholesterol oxides, fatty acid composition and oxidative stability of beef burgers, raw and packaged grilled at -18 ° C in two stages (storage for zero and 90 days). 96 cattle were confined, castrated male, Nellore, with about 380 kg of initial weight and average age of 24 months, fed soybean oil, sunflower, linseed and a control treatment without oil for 82 days. From the Longissimus muscle and subcutaneous fat of animals burgers were produced. The beef burgers receiving soybean oil had higher lipid stability for both zero and 90 days of storage as compared to other diets. The raw patties resulted in lower values for zero as well as 90 days of storage compared to the grill method. The animal burgers fed the flaxseed oil resulted in lower values for the attribute flavor. The burgers of storage time zero days resulted in higher grades by consumers for texture and overall acceptability compared to the samples stored for 90 days. The percentage of polyunsaturated fatty acids was decreased, regardless of the treatment after 90 days of storage. The CLA c9 t11 were found in larger quantities in samples of animals fed with linseed and soybean oils, and 90 to zero days of storage. The cholesterol content increased after samples of burgers were grilled, while there was no effect for the sources of oils and storage times. The presence of cholesterol oxides was observed after the samples were stored for 90 days, independent of the used oil sources. The supply of unsaturated oils to feedlot cattle increases the percentage of polyunsaturated fatty acids in hamburgers produced from meat and fat of these animals. The addition of vegetable oils for cattle increases lipid oxidation in hamburgers produced from meat and fat from these animals when compared to a treatment without addition of vegetable oils. Hamburgers produced from meat and fat animals fed with vegetable oils in the diet have higher lipid oxidation after 90 days of storage compared to burgers with zero storage time and the control treatment burgers, while the heat process is not responsible for the higher lipid oxidation.
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Somkhumphee, Yuphin, of Western Sydney Hawkesbury University, of Science Technology and Environment College e of Science Food and Horticulture School. "Development of reduced energy Thai style fresh pork sausages". THESIS_CSTE_SFH_Somkhumphee_Y.xml, 2001. http://handle.uws.edu.au:8081/1959.7/612.
Testo completoAbstract (sommario):
The development of a reduced energy Thai style fresh pork sausage has been achieved by replacing fat with carbohydrate and water. Replacing fat in the processed meat formulation with other ingredients is known to alter the product qualities. The addition of carbohydrate, namely mung bean vermicelli, as a fat replacement is suggested to improve the water holding capacity, cooking yield and textural properties as well as reduce the fat and total energy content. This research developed a standard processing methodology for a characteristic Thai fresh pork sausage. The research evaluated the potential of mung bean vermicelli in the formulation of a reduced energy Thai style fresh pork sausage. The reduced energy sausage was developed by replacing fat with 25%, 50%, 75%, and 100% soaked mung bean vermicelli. Quality characteristics of the sausages (chemical, textural and sensory) were evaluated and compared with control sausages (20% fat). The results of the present study indicated that soaked mung bean vermicelli offset many of the characteristic changes usually brought about by fat reduction. The sausages had a decreased cooking loss and an improved yield as well as a reduction in energy content. In addition, they maintained the textural and sensory characteristics of the control Thai style fresh pork sausages.Master of Science (Hons)
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Osuala, Chima I. "Modifying Lamb/Mutton Flavors in Processed Meat Products by Smoking, Curing, Spicing, Starter Cultures and Fat Modification. Investigating the Use of the Technicon InfraAlyzer 400R as a Rapid Method for Proximate Analysis". DigitalCommons@USU, 1985. https://digitalcommons.usu.edu/etd/5298.
Testo completoAbstract (sommario):
Mutton meat was tested in different products in order to obtain prototype products in which mutton can effectively be used without the objectionable mutton off flavor. Mutton flavor reduction was achieved in the processed meat products by: (a) lowering mutton fat to a level of 10% or less, (b) using spices, smoking and/or curing, (c) substituting fat from beef or pork for mutton fat, and (d) the action of microbial starter cultures. Four taste panel sessions were set up to rate these products against an all beef or all pork control for consumer acceptability. Taste panel results indicate that flavor had the greatest effect on overall acceptability of these products, compared to texture and appearance. Proximate meat analysis for fat, protein, moisture and ash were performed using the Technicon InfraAlyzer 400R and the results were compared with values obtained by reference AOAC methods. Correlation coefficients of 0.992, 0.867, 0.992 and 0.511 were obtained for fat, protein, moisture and ash respectively. The two methods were not significantly different (p = .05). These results indicate that the InfraAlyzer may be used as a rapid method for proximate analysis of fat, protein and moisture.
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Li, Zhen. "Epidemiological Study of Diet, Obesity and Asthma in the French EGEA Study". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS087/document.
Testo completoAbstract (sommario):
L’objectif principal de la thèse était d’étudier les effets de l’alimentation et de l’obésité sur l’asthme et son évolution, en prenant en compte des facteurs de médiations spécifiques.La première partie de la thèse visait à étudier le rôle de l’alimentation dans l'asthme, en prenant en compte l’indice de masse corporelle (IMC) comme un médiateur potentiel, et en évaluant l’effet modificateur du tabac dans ces associations. Ce travail a d’abord porté sur le rôle de la consommation de charcuterie, récemment classée cancérogène. Parmi 971 adultes de l’étude des facteurs génétiques et environnementaux de l’asthme (EGEA), nous avons montré qu’une consommation élevée de charcuterie (au moins 4 fois par semaine) était associée de façon directe à l’aggravation des symptômes de l’asthme, et que seulement 14% de l’association entre la consommation de charcuterie et l’asthme était expliqué par l’IMC (effet indirect). Ce travail a ensuite porté sur le rôle de la qualité globale de l’alimentation, évaluée par le score alimentaire Alternate Healthy Eating Index 2010. Parmi 969 participants d’EGEA, nous avons montré qu’une alimentation de qualité était associée de façon directe à une amélioration des symptômes de l’asthme chez les non-fumeurs. L’effet indirect lié à l’IMC n’était pas significatif. La deuxième partie de la thèse visait à mieux comprendre l'association entre l'obésité et l'activité de l’asthme, en prenant en compte la leptine, une adipokine pro-inflammatoire, comme un médiateur potentiel. Parmi 331 adultes d’EGEA avec un asthme actif à l’inclusion, les analyses ont montré que différentes mesures élevées de la composition corporelle étaient associées à une activité persistante de l’asthme, avec un effet indirect très fort de la leptine dans ces associationsThe general aim of the thesis was to study the role of diet and obesity in asthma, while accounting for potential mediators in these analyses.The first part of the thesis aimed to investigate the role of dietary factors in asthma at a “macro-level”, considering body mass index (BMI) as a potential mediator, and to evaluate effect modification by smoking. We first focused on processed meat intake, a recent carcinogen. Among 971 participants from the Epidemiological study on the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy (EGEA), analysis showed that high processed meat intake (at least 4 servings/week) was associated with worsening asthma symptoms over time, through a direct effect and to a lesser extent an effect mediated by BMI. We then focused on the overall diet quality assessed by the Alternate Healthy Eating Index 2010. Among 969 participants from the EGEA study, the analyses showed that a greater adherence to a better diet quality was associated with improved asthma symptoms over time in never smokers only and was not mediated through BMI. The second part of the thesis aimed to better understand the association between obesity and asthma at a “micro-level”, considering leptin, an inflammatory biological marker related to obesity, as a mediator. Including 331 participants from the EGEA study with current asthma at baseline, analysis showed that high body adiposity estimated by different measures was associated with persistent asthma activity, likely mediated by leptin
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Somkhumphee, Yuphin. "Development of reduced energy Thai style fresh pork sausages". Thesis, View thesis View thesis, 2001. http://handle.uws.edu.au:8081/1959.7/612.
Testo completoAbstract (sommario):
The development of a reduced energy Thai style fresh pork sausage has been achieved by replacing fat with carbohydrate and water. Replacing fat in the processed meat formulation with other ingredients is known to alter the product qualities. The addition of carbohydrate, namely mung bean vermicelli, as a fat replacement is suggested to improve the water holding capacity, cooking yield and textural properties as well as reduce the fat and total energy content. This research developed a standard processing methodology for a characteristic Thai fresh pork sausage. The research evaluated the potential of mung bean vermicelli in the formulation of a reduced energy Thai style fresh pork sausage. The reduced energy sausage was developed by replacing fat with 25%, 50%, 75%, and 100% soaked mung bean vermicelli. Quality characteristics of the sausages (chemical, textural and sensory) were evaluated and compared with control sausages (20% fat). The results of the present study indicated that soaked mung bean vermicelli offset many of the characteristic changes usually brought about by fat reduction. The sausages had a decreased cooking loss and an improved yield as well as a reduction in energy content. In addition, they maintained the textural and sensory characteristics of the control Thai style fresh pork sausages.
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Medina, Camila, e Monika Miljanovic. "EXPLORING DIGITALIZATION AND VALUE CO-CREATION IN THE FOOD INDUSTRY : Study on challenges and opportunities for digitalization and the impact on the customer offering". Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-36032.
Testo completoAbstract (sommario):
The purpose of this study is to identify the challenges and opportunities for digitalization within the food industry, and give suggestions on how to co-create value through digitalization. This qualitative study is based on data collected from scientific articles, reports and books about digitalization and value co-creation in the food industry. The primary data collection was carried out by twelve semi-structured interviews and a complementary food industry study with eleven respondents. The collected data was handled in thematic analysis and inspired by coding. The study’s main conclusion was the discovering of a new value co- creation mechanism defined as relationship and learning.
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Li, Yanting. "Monitoring and diagnosing the mean vector and covariance matrix of multistage processes /". View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?IELM%202008%20LI.
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Oliveira, Thales Leandro Coutinho de 1985. "High pressure processing optimization for low-sodium sliced ready-to-eat turkey breast with additional natural antimicrobial hurdle = Otimização do processamento a alta pressão para embutido de peru fatiado com teor reduzido de sódio combinado à uma barreira antimicrobiana natural". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254841.
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Orientador: Marcelo CristianiniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: A redução do cloreto de sódio nas formulações de alimentos processados representa um grande desafio para indústria moderna, tendo em vista a relação estabelecida entre o consumo elevado de sódio e a ocorrência da hipertensão arterial, principal fator de risco associado à ocorrência de distúrbios do cérebro e cardiovasculares. Em produtos cárneos, além de atuar sobre aspectos sensoriais e de textura, o sal desempenha papel chave sobre sua estabilidade microbiológica. Uma simples redução pode resultar em produtos instáveis durante sua vida de prateleira. Logo, para que estratégias de redução de sal sejam implementadas de maneira segura, faz-se necessário a aplicação de tecnologias ou agentes de preservação complementares. Tecnologias emergentes não-térmicas de inativação microbiana como o processamento à Alta Pressão (HPP - High Pressure Processing) surgem como opções factíveis para tal propósito, eliminando a dependência de conservantes químicos em face à redução de sal. A adição de agentes antimicrobianos naturais como barreiras adicionais à HPP (Tecnologia de Múltiplas Barreiras), visando potencializar os efeitos conservadores, têm sido apontada como uma promissora tendência na literatura moderna. Diante deste exposto, após determinação da formulação de trabalho com teor reduzido de sódio, a pesquisa objetivou ajustar as variáveis de processo "carga de pressão" e "tempo de residência" (utilizando baixas temperaturas de 25°C) para o processamento de embutido de peito peru fatiado embalado a vácuo (tipo "Blanquet"). Foram avaliadas respostas de inativação microbiana pós-processo (reduções logarítmicas) para populações inoculadas do patógeno Listeria monocytogenes e bactérias ácido láticas deterioradoras incluindo as espécies Leuconostoc mesenteroides e Lactobacillus sakei; também foram avaliados os atributos de qualidade incluindo cor, atividade de água, pH, sinerese, textura e oxidação lipídica. Em adição, visando à utilização de tecnologia de múltiplas barreiras para conservação, foi estudado o efeito da adição do componente bioativo carvacrol em concentrações de 200ppm, na formulação do produto. Empregando estratégia de simples redução, sem a adição sais substitutos, após avaliação de aspectos físico-químicos, sensoriais e microbiológicos, concluiu-se que níveis de 30% de redução de sal (cerca de 25% menos sódio) sobre o controle formulado com 20g/kg, são viáveis; entretanto, foi evidenciada redução da estabilidade microbiológica. Após avaliação de diferentes faixas de pressão e tempo de processo, seguindo os critérios exigidos de desempenho para inativação pós-processo de Listeria monocytogenes (4-5 reduções logarítmicas), um valor de 600MPa/180 segundos a 25°C se apresentou como um tratamento adequado para o produto com baixo teor de sódio estudado, promovendo reduções logarítmicas eficazes contra o patógeno-alvo estudado e a microbiota deteriorante. Alterações instrumentais (p<0.05) em alguns dos atributos de qualidade avaliados puderam ser destacadas principalmente sinerese, oxidação lipídica e textura; porém são necessários estudos mais amplos de análise sensorial. Adicionalmente, dados apresentados demonstraram que os consumidores não foram capazes de diferir o produto low-sodium processado por alta pressão isostática (600MPa/180sec/25°C) de um não pressurizado; de fato, apesar dos efeitos instrumentais significativos, estas alterações parecem não ser identificadas pelos consumidores. A adição de uma barreira natural complementar, o carvacrol, em níveis sensorialmente aceitáveis, foi capaz de potencializar os efeitos de inativação pós-processo (reduções logarítimicas) dos grupos microbianos alvo; efeitos benéficos combinados ao longo da estocagem refrigerada do produto também foram evidenciados por meio de reduzidas taxas de crescimento e fase lag aumentada, maximizando assim o potencial de conservação. A utilização combinada de HPP e carvacrol representou uma alternativa promissora contra fenômenos de injúrias sub-letais e recuperação celular. Sugere-se que a intensidade do processo HPP (em termos de carga de pressão, tempo de processo e temperatura) necessária para inativar microrganismos em níveis requeridos, possa ser reduzida na presença de barreiras antimicrobianas adicionais, garantindo a qualidade total do produto processado em condições mais amenas. Em adição, uma série de vantagens industriais podem ser destacadas tais como a redução de custos para a instalação de equipamento inicial e de manutenção (equipamentos operando em cargas mais baixas); e maximização da produção de processamento por ciclos efetivamente encurtados (ciclos de produtividade mais elevados por hora)
Abstract: The reduction of sodium chloride in processed food formulations represents a great challenge for modern industry, considering the relationship established between high sodium intake and the occurrence of arterial hypertension, the major risk factor associated with the occurrence of cardiovascular diseases and strokes. In meat products, in addition to acting on sensory quality and texture, salt plays a key role on the microbiological stability. A simple reduction can result in unstable products during their shelf-life. Therefore, for the success of salt reduction strategies implemented safely, it is necessary the application of complementary technologies or alternative preservatives. Non-thermal emerging technologies for microbial inactivation, such as High Pressure Processing (HPP), appear as feasible alternative for this purpose, eliminating the dependence of chemical preservatives considering the reduction of salt barrier. The addition of natural antimicrobial agents as additional hurdles (Multi Hurdle Technology) to the HPP, aiming to enhance the preservative effects, has been identified as a promising trend in modern literature. Given this exposed, after determination of low-sodium working formulation, this research aimed adjust the processing variables "pressure load" and "dwell time" (using low-processing temperatures of 25°C) for sliced vacuum-packaged ready-to-eat turkey breast. Post-processing microbial inactivation responses were evaluated (by logarithmic reductions) against inoculated populations of the target pathogen Listeria monocytogenes and spoilage lactic acid bacteria including Leuconostoc mesenteroides and Lactobacillus sakei; were also evaluated quality-attributes including color, water activity, pH, syneresis, texture and lipid oxidation. In addition, in order to use multiple barriers for preservation technology, was studied the effect of adding bioactive component, carvacrol at concentrations of 200ppm in the product formulation. Employing a simple reduction strategy, without adding salt substitutes, after evaluation of physicochemical aspects, sensory and microbiological, it was concluded that levels of 30% NaCl reduction (aproximatelly 25% less sodium) on the control made with 20g/kg, are viable; however, problems with microbiological stability were evidenced. After evaluation of different pressure ranges and processing time, following the performance criteria required for post-inactivation process Listeria monocytogenes (4-5 log reduction), a value of 600MPa/180 seconds at 25°C was presented with an adequate treatment for studied product with low sodium content, promoting effective logarithmic reductions against the studied target pathogen and spoilage LAB. Instrumental changes (p<0.05) in some of the evaluated quality attributes could be revealed mainly in syneresis, lipid oxidation and texture; however, a sensory confirmation needs to be established. Additionally, data presented showed that consumers have not been able to differ low-sodium products processed by HPP (600MPa/180sec/25°C) and unpressurised; in fact, despite significant instrumental effects, these changes seems to be not identified by consumers. The addition of natural barrier, such as carvacrol at acceptable sensory levels (200ppm), was able to potentiate the effects of post-process inactivation (logarithmic reductions) of the target microbial groups; combined benefit effects along the refrigerated product storage were also evidenced by reduced growth rates and increased lag phases, thus maximizing their potential for conservation. The combination of HPP and carvacrol represented a promising weapon against phenomena of sub-lethal injuries and cell recovery. It is suggested that the intensity of the HPP process (in terms of pressure load, process time and temperature) required to inactivate microorganisms in required levels, may be reduced in the presence of additional microbial barriers, ensuring the overall quality of the processed product under mild processing conditions. In addition, a number of industrial advantages can be highlighted such as reduced costs for the initial installation and maintenance equipment (low required pressure loads) and maximization of production by effectively processing cycles shortened (higher productivity cycles per hour)
Doutorado
Tecnologia de Alimentos
Doutor em Tecnologia de Alimentos
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Lin, Shyh-Hsiang. "Meat analog development and physical, chemical, and sensory properties /". free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9924899.
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Hue, Chau Kuo. "O mercado de frios no Brasil: uma estimação da demanda a partir de um modelo em três estágios". reponame:Repositório Institucional do FGV, 2011. http://hdl.handle.net/10438/8332.
Testo completoAbstract (sommario):
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O trabalho estima um sistema de equações de demanda para os produtos do mercado de frios no Brasil, utilizando o modelo Almost Ideal Demand System (AIDS) em três estágios. O passo seguinte à estimação das equações de demanda é a avaliação das elasticidades própria e cruzada obtidas, verificando se estas são condizentes com as previsões da teoria econômica, o que permitiria a utilização destas para simular os efeitos de uma fusão entre as empresas Sadia e Perdigão no mercado de frios. Apenas os resultados dos estágios superior e intermediário – no qual são estimadas as elasticidades relativas aos diferentes tipos de frios, como presunto e salame – estão de acordo com o que seria previsto pela teoria. Já no estágio inferior, onde se estimam as elasticidades relativas às diferentes marcas para cada tipo de frio, isso não acontece. Uma provável causa dessa inconsistência nos resultados está relacionada ao problema de endogeneidade inerente à estimação de equações de demanda com dados agregados, uma vez que, para o estágio inferior, não foi possível obter variáveis instrumentais suficientemente correlacionadas com as variáveis endógenas. Dados os resultados insatisfatórios para o estágio inferior, a simulação de fusão não foi feita. O trabalho apenas discute as inevitáveis inconsistências que ocorreriam na simulação de fusão em decorrência do uso de resultados incoerentes do ponto de vista teórico.
This work estimates a system of demand equations for the Brazilian processed meat products, using the Almost Ideal Demand System (AIDS) in three stages. The next step after the demand equation estimation is to evaluate the own and cross elasticities, verifying if its values is consistent with the economic theory, which would allow to use them to simulate the effects of the merge between Sadia and Perdigão. Only in the top and middle level equations – where the elasticities relative to the processed meat products such as ham and salami are estimated – the results are consistent with the economic theory. However, in the bottom level, where the elasticities among the different brands in each product are calculated, this doesn’t happen. One possible cause of this inconsistency in the outputs may be related to the endogeinity inherent in the demand equations estimation with aggregated data, once in the bottom level it was not possible to get instrumental variables sufficiently correlated with the endogenous variables. Due to the unsatisfying outputs of the bottom level, the merger simulation was not done. The work just discuss the inevitable inconsistencies that would occur in the merge simulation caused by the incoherent results.
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Akin, Osman Caglar Grigolini Paolo. "Perturbation of renewal processes". [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-6140.
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Lee, Parker Walter. "Melt Processed Polymer/Protein Materials for Sustained Drug Delivery". Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1508886279190443.
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Byrne, Caitriona Martina. "Survival and persistence of Escherichia coli 0157:H7 within meat production processes". Thesis, University of Ulster, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365916.
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Hurtado, Alegria Julio Ariel. "A meta-process for defining adaptable software processes". Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/111945.
Testo completoAbstract (sommario):
Doctor en Ciencias, Mención ComputaciónLograr proyectos de software productivos y con calidad dentro de una industria dinámica y competitiva, requiere definir modelos de proceso correctos y adecuados al contexto. Así, el mejor proceso debe estar correctamente definido y debe ser adecuado a las particularidades del proyecto en el que será usado. Típicamente, un ingeniero de procesos define un proceso específico para cada proyecto en forma ad-hoc, lo cual resulta costoso, irrepetible y propenso al error. Por otro lado, la especificación de procesos demanda un esfuerzo enorme y una vez éstos son especificados, son pocos los enfoques y aún menos las herramientas, que asistan al ingeniero de procesos a analizar la calidad de sus modelos de proceso. En los últimos cinco años hemos asesorado empresas de software en la especificación de sus procesos de software. Como parte de este trabajo una serie de problemas fueron identificados, éstos indican la presencia potencial de incorrectas concepciones y especificaciones, así como inadecuadas adaptaciones en el modelo del proceso. Para prevenir errores en la adaptación de procesos, esta tesis propone CASPER, un metaproceso para definir modelos de proceso adaptables al contexto. CASPER usa un enfoque basado en modelos para adaptar el proceso de desarrollo generando procesos específicos a proyectos a partir del proceso organizacional y el contexto específico del proyecto. El enfoque es sistemático, repetible y no depende de un usuario experto en ingeniería de procesos. Para asistir al ingeniero de procesos en el análisis de problemas concepuales y de especificación, en esta tesis se desarrolló AVISPA. AVISPA es una herramienta que gráficamente presenta diferente patrones de error de un modelo de proceso de software resaltando los errores potenciales a través de indicadores comprensibles e intuitivos. Los enfoques de CASPER y AVISPA han sido validados aplicándolos en la definición y análisis de algunos modelos de proceso de la industria de software Chilena y algunos procesos públicos disponibles desde la comunidad de Eclipse Process Framework. Estos enfoques muestran ampliamente la utilidad práctica del enfoque dirigido por modelos para lograr modelos de proceso de alta calidad.
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Takahashi, Ken. "Processes controlling the mean tropical Pacific precipitation pattern /". Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/10069.
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Liu, Hao. "Semiparametric marginal mean models for multivariate counting processes /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9542.
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Bianco, Simone Grigolini Paolo. "Complexity as aging non-Poisson renewal processes". [Denton, Tex.] : University of North Texas, 2007. http://digital.library.unt.edu/permalink/meta-dc-3706.
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Gu, Xin. "Directed melt oxidation of aluminium : processing and microstructure relationships". Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388706.
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Sun-Hosoya, Lisheng. "Meta-Learning as a Markov Decision Process". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS588/document.
Testo completoAbstract (sommario):
L'apprentissage automatique (ML) a connu d'énormes succès ces dernières années et repose sur un nombre toujours croissant d'applications réelles. Cependant, la conception d'algorithmes prometteurs pour un problème spécifique nécessite toujours un effort humain considérable. L'apprentissage automatique (AutoML) a pour objectif de sortir l'homme de la boucle. AutoML est généralement traité comme un problème de sélection d’algorithme / hyper-paramètre. Les approches existantes incluent l’optimisation Bayésienne, les algorithmes évolutionnistes et l’apprentissage par renforcement. Parmi eux, auto-sklearn, qui intègre des techniques de meta-learning à l'initialisation de la recherche, occupe toujours une place de choix dans les challenges AutoML. Cette observation a orienté mes recherches vers le domaine du meta-learning. Cette orientation m'a amené à développer un nouveau cadre basé sur les processus de décision Markovien (MDP) et l'apprentissage par renforcement (RL). Après une introduction générale (chapitre 1), mon travail de thèse commence par une analyse approfondie des résultats du Challenge AutoML (chapitre 2). Cette analyse a orienté mon travail vers le meta-learning, menant tout d’abord à proposer une formulation d’AutoML en tant que problème de recommandation, puis à formuler une nouvelle conceptualisation du problème en tant que MDP (chapitre 3). Dans le cadre du MDP, le problème consiste à remplir de manière aussi rapide et efficace que possible une matrice S de meta-learning, dans laquelle les lignes correspondent aux tâches et les colonnes aux algorithmes. Un élément de matrice S (i, j) est la performance de l'algorithme j appliqué à la tâche i. La recherche efficace des meilleures valeurs dans S nous permet d’identifier rapidement les algorithmes les mieux adaptés à des tâches données. Dans le chapitre 4, nous examinons d’abord le cadre classique d’optimisation des hyper-paramètres. Au chapitre 5, une première approche de meta-learning est introduite, qui combine des techniques d'apprentissage actif et de filtrage collaboratif pour prédire les valeurs manquantes dans S. Nos dernières recherches appliquent RL au problème du MDP défini pour apprendre une politique efficace d’exploration de S. Nous appelons cette approche REVEAL et proposons une analogie avec une série de jeux pour permettre de visualiser les stratégies des agents pour révéler progressivement les informations. Cette ligne de recherche est développée au chapitre 6. Les principaux résultats de mon projet de thèse sont : 1) Sélection HP / modèle : j'ai exploré la méthode Freeze-Thaw et optimisé l'algorithme pour entrer dans le premier challenge AutoML, obtenant la 3ème place du tour final (chapitre 3). 2) ActivMetaL : j'ai conçu un nouvel algorithme pour le meta-learning actif (ActivMetaL) et l'ai comparé à d'autres méthodes de base sur des données réelles et artificielles. Cette étude a démontré qu'ActiveMetaL est généralement capable de découvrir le meilleur algorithme plus rapidement que les méthodes de base. 3) REVEAL : j'ai développé une nouvelle conceptualisation du meta-learning en tant que processus de décision Markovien et je l'ai intégrée dans le cadre plus général des jeux REVEAL. Avec un stagiaire en master, j'ai développé des agents qui apprennent (avec l'apprentissage par renforcement) à prédire le meilleur algorithme à essayer. Le travail présenté dans ma thèse est de nature empirique. Plusieurs méta-données du monde réel ont été utilisées dans cette recherche. Des méta-données artificielles et semi-artificielles sont également utilisées dans mon travail. Les résultats indiquent que RL est une approche viable de ce problème, bien qu'il reste encore beaucoup à faire pour optimiser les algorithmes et les faire passer à l’échelle aux problèmes de méta-apprentissage plus vastesMachine Learning (ML) has enjoyed huge successes in recent years and an ever- growing number of real-world applications rely on it. However, designing promising algorithms for a specific problem still requires huge human effort. Automated Machine Learning (AutoML) aims at taking the human out of the loop and develop machines that generate / recommend good algorithms for a given ML tasks. AutoML is usually treated as an algorithm / hyper-parameter selection problems, existing approaches include Bayesian optimization, evolutionary algorithms as well as reinforcement learning. Among them, auto-sklearn which incorporates meta-learning techniques in their search initialization, ranks consistently well in AutoML challenges. This observation oriented my research to the Meta-Learning domain. This direction led me to develop a novel framework based on Markov Decision Processes (MDP) and reinforcement learning (RL).After a general introduction (Chapter 1), my thesis work starts with an in-depth analysis of the results of the AutoML challenge (Chapter 2). This analysis oriented my work towards meta-learning, leading me first to propose a formulation of AutoML as a recommendation problem, and ultimately to formulate a novel conceptualisation of the problem as a MDP (Chapter 3). In the MDP setting, the problem is brought back to filling up, as quickly and efficiently as possible, a meta-learning matrix S, in which lines correspond to ML tasks and columns to ML algorithms. A matrix element S(i, j) is the performance of algorithm j applied to task i. Searching efficiently for the best values in S allows us to identify quickly algorithms best suited to given tasks. In Chapter 4 the classical hyper-parameter optimization framework (HyperOpt) is first reviewed. In Chapter 5 a first meta-learning approach is introduced along the lines of our paper ActivMetaL that combines active learning and collaborative filtering techniques to predict the missing values in S. Our latest research applies RL to the MDP problem we defined to learn an efficient policy to explore S. We call this approach REVEAL and propose an analogy with a series of toy games to help visualize agents’ strategies to reveal information progressively, e.g. masked areas of images to be classified, or ship positions in a battleship game. This line of research is developed in Chapter 6. The main results of my PhD project are: 1) HP / model selection: I have explored the Freeze-Thaw method and optimized the algorithm to enter the first AutoML challenge, achieving 3rd place in the final round (Chapter 3). 2) ActivMetaL: I have designed a new algorithm for active meta-learning (ActivMetaL) and compared it with other baseline methods on real-world and artificial data. This study demonstrated that ActiveMetaL is generally able to discover the best algorithm faster than baseline methods. 3) REVEAL: I developed a new conceptualization of meta-learning as a Markov Decision Process and put it into the more general framework of REVEAL games. With a master student intern, I developed agents that learns (with reinforcement learning) to predict the next best algorithm to be tried. To develop this agent, we used surrogate toy tasks of REVEAL games. We then applied our methods to AutoML problems. The work presented in my thesis is empirical in nature. Several real world meta-datasets were used in this research. Artificial and semi-artificial meta-datasets are also used in my work. The results indicate that RL is a viable approach to this problem, although much work remains to be done to optimize algorithms to make them scale to larger meta-learning problems
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Sutanto, Elmawati Laksmani. "Mean-tracking algorithm for multivariable cluster analysis in manufacturing processes". Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394557.
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Gomes, Fabrício Maciel [UNESP]. "Diferentes métodos de aglutinação para melhoria de processos com múltiplas respostas". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/132419.
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Empresas não medem esforços para aperfeiçoar seus processos e produtos de acordo com diferentes critérios para satisfazer as exigências e necessidades dos clientes em busca de um padrão de competitividade superior ao de suas concorrentes. Neste cenário é muito comum a necessidade de se estabelecer condições que resultem na melhoria de mais de um critério de forma simultânea. Neste trabalho foi realizada uma avaliação da utilização de quatro métodos que utilizam as Meta-heurísticas Recozimento Simulado, Algoritmo Genético, Recozimento Simulado combinado com o método Nelder Mead Simplex e algoritmo genético combinado com o método Nelde-Mead simplex para o estabelecimento de melhoria das condições de processos com múltiplas respostas. Para a avaliação dos métodos propostos foram utilizados problemas-teste criteriosamente selecionados na literatura de forma a serem analisados casos com diferente número de variáveis, número de respostas e tipos de resposta. A aglutinação das respostas foi realizada por quatro métodos diferentes: Desirability, Desvio Médio Percentual, Programação por Compromisso e Programação por Compromisso normalizada pela distância euclidiana. A avaliação dos métodos foi realizada por meio de comparação entre os resultados obtidos na utilização de um mesmo método de aglutinação, determinando assim a eficiência do método de busca. Os resultados obtidos na avaliação dos métodos sugerem a aplicação do método do algoritmo genético quando se pretende estabelecer parâmetros que resultem na melhoria de processos com múltiplas respostas, em particular quando essas respostas são modeladas por equações com termos cúbicos, independentemente do número de termos que possam conter, do tipo de respostas e do número de variáveis.
Companies go to great lengths to improve its processes and products according to different criteria to meet the demands and needs of customers looking for a higher standard of competitiveness to that of their competitors. This scenario is very common the need to establish conditions that result in the improvement of more than one criterion simultaneously. This work was carried out an evaluation of the use of four methods that use Metaheuristics Simulated Annealing, Genetic Algorithms, Simulated Annealing combined with the Nelder Mead Simplex method and genetic algorithm combined with Nelde Mead simplex method for the improvement of establishing the conditions of processes with multiple answers. For the evaluation of the proposed test methods were used in the literature problems carefully selected in order to be analyzed cases with different numbers of variables, response numbers and types of responses. In this research we used the average percentage deviation function as a way to bring together the answers. The agglutination of the answers was performed by four different methods: Desirability, Average Percentage Deviation, Compromise Programming and Compromise Programming normalized by Euclidean distance. The evaluation method was performed by comparison between the results obtained in using the same bonding method, thereby determining the efficiency of the search method. The results obtained in the evaluation of the methods suggest the application of the genetic algorithm method when you want to set parameters that result in the improvement of processes with multiple answers, particularly when these responses are modeled by equations with cubic terms, regardless of the number of terms that can contain the type of responses and the number of variables.
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Brandão, Luciano. "Sequenciamento de processadores paralelos utilizando a meta heurística busca Tabu". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2002. http://hdl.handle.net/10183/29561.
Testo completoAbstract (sommario):
A programação de tarefas em linhas de produção nas empresas sempre foi e continua sendo um elemento fundamental para o sucesso das organizações em um mercado tão globalizado e competitivo. A melhor utilização dos recursos instalados através da melhor alocação das tarefas gerará melhores resultados para a organização. Entende-se pela melhor utilização dos recursos a redução do tempo total de finalização das tarefas (makespan) sem prejudicar o atendimento da data de entrega. Aplica-se esta idéia para as indústrias de um modo geral, que tenham linhas de produção, podendo citar a indústria calçadista, foco neste trabalho, as indústrias de massas, biscoitos e balas, entre outras. Na literatura especializada, esta programação é conhecida como sequenciamento de tarefas em processadores. Neste trabalho aplicado junto a indústria calçadista, foca-se em uma área mais específica: o sequenciamento de tarefas em processadores paralelos. Os problemas de sequenciamento se caracterizam pela grande exigência computacional para a resolução com algoritmos de otimização. Isto remete a utilização de heurísticas para a resolução destes problemas. Neste trabalho explora-se a Meta-Heurística Busca Tabu, que se apresentou com resultados muito bons em relação ao ótimo e em relação ao trabalhador humano.The jobs scheduling in processor lines in the companies was always, and continues being, a fundamental element to the organization’s success in a very globalized and competitive market. The best use of the installed resources, through the best distribution of the jobs will generate better results for the organization. The best utilization of the resources means the reduction of the makespan without prejudicing the due-date. This idea is applied to all industries in general, that have processor lines, for example the shoes factories, focused in this research, pasta, cookies and sugar balls factories, beyond others. In the specialized literature this subject is know as job scheduling. This researh is applyed to a shoes factory is focused on more specific area: the job scheduling in parallel machines. The scheduling problems are characterized on its computational difficulty using optimization algoritms. That is the reason why we used heuristics to solve these problems. In this research we explore the Meta-Heuristic Tabu Search, wich showed very good results comparing to the optimun and comparing to the human worker.
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Pitchai, Karthik Raja. "An executable meta-model for safety oriented software and systems development processes within the avionics domain in compliance with RTCA DO 178 B". Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-19296.
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"There are two critical points in every aerial flight—its beginning and its end." — Alexander Graham Bell, 1906. From beginning till the end, the safety critical software plays a vital role in avionics and hence its development and its certification are indispensable. “RTCA DO-178B- Software Considerations in Airborne Systems and Equipment Certification” provides the normative guidelines to develop such systems. In particular, this standard provides the safety protocol and processes that should be followed to achieve safe systems. The safety guideline of DO178B emphasizes more on better documentation, communication and visibility into actual process. For realizing the guidelines of DO178B, a well-defined and collectively accepted (at least at the development team–level) interpretationof the protocol and processes is needed. To achieve such interpretation, a well-defined modeling language that models the process with safety construct is essential. The Object Management Group’s Software and System Process Engineering Metamodel SPEM 2.0 standard provides specification for modeling software and systems development processes. SPEM2.0, however, is a general purpose language and does notprovide sufficient coverage in terms of language constructs to address safety concerns. This thesis proposes S-SPEM, an extension of the SPEM2.0 to allow users to specify safety-oriented processes for the development of safety critical systems in the context of RTCA DO 178B. The DO178B is analyzed to capture the safety related process elements and SPEM 2.0 is extended to include those safety concepts. Moreover, to simulate and validate the modeled processes, S-SPEMconcepts are mapped onto XML Process Definition Language (XPDL) concepts and a transformation algorithm is sketched. Finally, a case-study will illustrate theusage and effectiveness of the proposed extension.
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Ng, Yean Thye. "Electrically conductive melt-processed blends of polymeric conductive additives with styrenic thermoplastics". Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/11016.
Testo completoAbstract (sommario):
The growing demand in portable and compact consumer devices and appliances has resulted in the need for the miniaturisation of electronic components. These miniaturised electronic components are sensitive and susceptible to damage by voltages as low as 20V. Electrically conductive styrenic thermoplastics are widely used in electronic packaging applications to protect these sensitive electronic components against electro-static discharge (ESD) during manufacturing, assembly, storage and shipping. Such ESD applications often require the optimal volume resistance range of ≥ 1.0x105 to < 1.0x108 Ω. The best known method to render styrenic thermoplastics conductive is by the incorporation of conductive fillers, such as carbon black but the main limitation is the difficulty in controlling the conductivity level due to the steep percolation curve. Thus the aim of this research is to develop electrically conductive styrenic thermoplastics by blending several styrenic resins with polymeric conductive additives to achieve optimal volume resistance range for ESD applications with the ease in controlling the conductivity level.
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Xiang, Dong. "Processing and properties of melt processed high density polyethylene-carbon nanofiller composites". Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.676504.
Testo completoAbstract (sommario):
The main aim of this work was to investigate the process-structure-property relationship of high density polyethylene (HOPE)/carbon nanofiller composites. A secondary aim was to develop thin thermoplastic films with enhanced electrical and mechanical properties for the potential use in aerospace applications. Three types of carbon nanofillers with different dimensions, multi-walled carbon nanotubes (MWCNTs), graphite nanoplatelets (GNPs) and carbon black (CB) respectively, were used to reinforce the polymer matrix. The melt-mixed HOPE/carbon nanofiller composites were processed by compression moulding, biaxial stretching and blown film extrusion, and the structure and properties of the resulting composites were characterised. The crystallinity and melting temperature of the material are barely influenced by the addition of carbon nanofillers, while the crystallization temperature is slightly increased due to a heterogeneous nucleation effect. The incorporation of carbon nanofillers has a positive effect on the modulus of the composites studied and a negative effect on the stress at break and strain at break. The relative effectiveness of generating rheological and conductive networks in the polymer is as follows: GNPs < CB < MWCNTs. The inclusion of carbon nanofillers led to significant strain hardening during the biaxial stretching of the material. The carbon nanofillers were further dispersed in the matrix by biaxial stretching. The mechanical properties of all the HOPE/carbon nanofiller composites were clearly improved after biaxial stretching. However, the volume resistivity of biaxially stretched HOPE/carbon nanofiller composites, at loadings lower than 4 wt%, was increased due to the deagglomeration of nanofillers and increased inter-particle distance. Blown films of the HOPE/MWCNT composites were manufactured at blow-up-ratios (BURs) of 2 to 3. The stress at break and strain at break of the composite films increases steadily with increasing BURs. Blown film extrusion also has a destructive effect on the conductive network of MWCNTs. However, there is no significant increase in the resistivity of the composite containing 8 wt% MWCNTs after film blowing at increasing BURs due to a sufficient density of nanotubes forming a robust conductive network .
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Ek, Elmqvist Malin. "Cook chill – Processen vid införandet av ett nytt matlagningssystem". Thesis, Örebro universitet, Restaurang- och hotellhögskolan - Grythytte Akademi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-16567.
Testo completoAbstract (sommario):
Bakgrund: Mat till svaga och sjuka äldre är en viktig del av den medicinska behandlingen. Äldre individer drabbas ofta av viktförlust på grund av ät svårigheter vilket kan leda till undernäring, det främsta nutritionsproblemet i Sverige. Matservicen är en viktig del inom äldreomsorgen. Det kommer nya metoder för att denna service ska kunna producera stora mängder av mat på ett praktiskt sätt, med tanke på ekonomi och resurser. Men även med tanke på matsäkerhet, sensoriskt perspektiv och nutritionsegenskaper. Införandet av nya styrdokument inom matdistribution kräver tänkande på fysiologiska faktorer om mat, näring och måltidens olika perspektiv. Det är ofta dietister och kostvetare i samarbete med kostchefer som tar fram nya matsystem, vilket ska skänka tankar på varje enskild individ. Det matsystem de flesta kommuner väljer att införa är Cook chill, maträtterna tillagas på sedvanligt sätt som sedan kyls ner inom 30 minuter. Maten får endast förvaras i högst fem dagar, detta inkluderar tillagnings- och förbrukningsdag.Syftet: med uppsatsen är att beskriva processen för att utveckla kostorganisationen för äldreomsorgens måltider i tre olika kommuner.Metod & material: Uppsatsen består av tre kvalitativa intervjuer av kostchefer från tre olika kommuner i Sverige. De intervjuer som genomfördes koncentrerades framförallt på för- och nackdelar med cook chill, även vad som händer när en kommun går från ett matlagningssystem till ett annat.Resultatet åskådliggör att de främsta anledningarna till att cook chill kom på tal i de undersökta kommunerna var ekonomisk fördel med tanke på transporter. Samt skapa ett säkert matsystem som kan tillagas och förvaras under en lång tid. Äldre individer som tidigare har varit i behov av specialkoster på grund av undernäring har minskat med Cook chill systemet, eftersom de får välja vad de vill äta och när de vill inta födan. Cook chill ger därför ett positivt utslag i de kommuner som i ett tidigt stadium informerade invånarna om fördelarna med införandet av Cook chill.Slutsats: Det är dock för tidigt att dra några slutsatser om Cook chill eftersom systemet inte har brukats länge i de kommuner som undersöks och det krävs en noggrann utvärdering. Med tanke på näringsinnehåll, matsäkerhet, behovet av närhet och daglig social samvaro vet vi inte ännu vilka konsekvenser det får för de äldre.Nyckelord: Äldreomsorg, Cook chill, nutrition, matdistribution, kommun.C-uppsatser
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Fabri, José Augusto. "Uma proposta de modelo para a criação e a organização de processos de produção em um contexto de fábrica de software". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3136/tde-01082007-161855/.
Testo completoAbstract (sommario):
Este trabalho tem como objetivo propor um modelo para a criação e organização de um processo fabril de produção de software. Para atingir este objetivo foram mapeadas 11 empresas de produção de software com características fabris, 6 brasileiras (o autor deste trabalho não possui uma autorização forma para divulgar o nome das empresas) e 5 estrangeiras (as japonesas Hitachi, Toshiba, NEC, Fujtsu e a americana SDC). Salienta-se que os dados utilizados neste trabalho sobre as empresas estrangeiras foram extraídos de CUSUMANO (1991). É importante salientar que todas as fábricas brasileiras que se propuseram a participar do estudo de caso possuem certificação de qualidade em processos comprovada (CMMI e/ou ISO). Após a apresentação dos casos é realizada uma comparação entre os processos fabris brasileiros e estrangeiros. Uma aderência do processo de produção de software mapeados nas empresas ao modelo proposto, também, é desenvolvida no trabalho. Por fim, 01 caso real apresentando o comportamento do modelo proposto na criação de um processo fabril, também, se caracteriza como um dos pontos a ser destacado.This work has as objective to propose a model to create and to organize a production process with factory software characteristic. To reach this objective 11 software production companies were mapped, 6 Brazilian (the author of this work doesn\'t possess an authorization to publish the name of the companies) and 5 foreigners (Hitachi, Toshiba, NEC, Fujtsu and SDC). The data used in this work, on the foreign companies were extracted of CUSUMANO (1991). All the Brazilian factories that participate of this case study possess quality certification in processes (CMMI and/or ISO). After the presentation of the cases a comparison between the Brazilian factories and the foreigners\' factories is developed. An adherence of the software production process mapped in the companies to the proposed model, also, is showed in the work. A real case presenting the behavior of the model proposed in the creation software production process, also, is characterized in the text (12 cases in the total).
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Marchetta, Natalie Dominique Jenny. "Cognitive processes in adults with ADHD". Maastricht : Maastricht : Universitaire Pers Maastricht ; University Library, Universiteit Maastricht [host], 2007. http://arno.unimaas.nl/show.cgi?fid=9380.
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Vergés, Fortià Vila. "Finite dimensional optimal linear mean square filter for continuos time Markovian jump linear systems". Laboratório Nacional de Computação Científica, 2017. https://tede.lncc.br/handle/tede/277.
Testo completoAbstract (sommario):
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Made available in DSpace on 2018-06-27T12:32:06Z (GMT). No. of bitstreams: 1 Dissertacao_final_Fortia.pdf: 758629 bytes, checksum: 6b31d1df1ed8f464b298cce7e1ee4180 (MD5) Previous issue date: 2017-02-24
Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ)
Stochastic differential equations with Markovian jump parameters constitute one of the most important class of hybrid dynamical systems, which has been extensively used for the modeling of dynamical systems which are subject to abrupt changes in their structure. The abrupt changes can be due, for instance, to abrupt environmental disturbances, component failure, volatility in economic systems, changes in subsystems interconnections, abrupt changes in the operation of a nonlinear plant, etc. This can be found, for instance, in aircraft control systems, robot systems, large flexible structure for space station, etc. We shall be particularly interested in the linear class which is dubbed in the literature as the class of Markov jump linear systems (MJLS). The jump mechanism is modeled by a Markov process, which is also known in the literature as the operation mode. The dissertation address the filtering problem of the operation mode for the class of MJLS. Previous result in the literature on this problem has been obtained by Wonham, which has shown the existence of an optimal nonlinear filter for this problem. The main hindrance with Wonham’s result, in the context of the control problem with partial observation of operation mode, is that it introduces a great deal of nonlinearity in the Hamilton-Jacobi- Belman equation, which makes it difficult to get an explicit closed solution for the control problem. Motivated by this, the main contribution of this dissertation is to devise an optimal linear filter for the mode operation, which we believe could be more favorable in the solution of the control problem with partial observations. In addition, relying on Murayama’s stochastic numerical method and the results of Yuan and Mao, we carry out simulation of Wonham’s filter, and the one devised in the dissertation, in order to compare their performances.
As equações diferenciais estocáticas com salto Markoviano constituem uma das clases de sistemas dinâmicos híbridos mais importantes, e tem sido muito usados para modelar sistemas sujeitos a mudanças abruptas na sua estructura. Essas mudanças podem ser devido a, por exemplo, perturbações ambientais, falhas em componentes, volatilidade em sistemas econômicos, mudanças em interconexões de subsistemas, mudanças abruptas em operações de plantas não lineares, etc. Estas falhas podem ser encontradas em sistemas de controle para aeronaves, sistemas robóticos, estructuras grandes e flexíveis em estações espaciais, etc. Nós estamos especialmente interessados na clase de sistemas lineares que é referenciada na literatura como sistemas lineares com salto Markoviano (SLSM). O mecanismo de salto é modelado por um processo de Markov, que é conhecido na literatura como modo de operação do sistema. Essa dissertação visa o problema de filtragem para o modo de operação do sistema linear com salto. Na literatura pode-se encontrar resultados já obtidos para esse problema como é o caso do filtro ótimo não linear deduzido por Wonham. Mas no contexto de controle ótimo com observações parciais do modo de operação, o filtro de Wonham introduz não linearidades na equação de Hamilton-Jacobi-Belman, fazendo com que seja muito complexo obter uma solução fechada para o problema de controle. A principal motivação desta dissertação é deduzir o filtro ótimo linear para o modo de operação, já que esta pode ser uma solução mais favorável para o problema de controle ótimo. Finalmente, usando o método numérico para equações diferenciais estocásticas de Euler-Murayama e o resultado de Yuan e Mao, realizamos a simulação do filtro de Wonham tal como o filtro deduzido neste trabalho, com o objetivo de comparar as respectivas performances.
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Selani, Miriam Mabel. "Extrato de bagaço de uva como antioxidante natural em carne de frango processada e armazenada sob congelamento". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-25052010-094238/.
Testo completoAbstract (sommario):
A carne de frango, em razão da elevada concentração de ácidos graxos insaturados, é altamente suscetível ao processo de oxidação lipídica, que afeta sabor, aroma, cor e textura dos alimentos, limitando sua estabilidade e vida-útil. Devido à possível toxicidade dos antioxidantes sintéticos e à demanda atual por produtos mais saudáveis, o uso de antioxidantes naturais, como o extrato de semente e casca de uva, representa uma alternativa na prevenção da oxidação lipídica em carne de frango, além de permitir aproveitamento do resíduo do processamento do vinho e suco de uva. Assim, o objetivo deste trabalho foi avaliar extratos de bagaço de uva (sementes e cascas) das variedades Isabel e Niágara (Vitis labrusca L.) quanto à atividade antioxidante em carne de frango processada crua e cozida. Foram adicionados à carne de frango 4 tipos de antioxidantes: butilhidroxitolueno; mistura comercial de eritorbato de sódio, ácido cítrico e açúcar; extrato de semente e casca de uva Isabel; extrato de semente e casca de uva Niágara; além do tratamento controle, sem antioxidante. A carne de frango foi processada no formato de mini-hambúrgueres, embalada a vácuo e armazenada sob congelamento (-18°C), durante 9 meses. As amostras foram caracterizadas através da determinação da composição centesimal. A cada três meses, foram realizadas análises de pH, cor instrumental, avaliação microbiológica, oxidação lipídica (valor das substâncias reativas ao ácido tiobarbitúrico TBARS) e análise sensorial. Não foi verificada alteração significativa (p>0,05) na composição centesimal e no valor de pH de amostras cruas e cozidas, em nenhum dos tratamentos analisados. Ambos os extratos de bagaço de uva mostraram efeito na inibição da oxidação lipídica da carne de frango crua e cozida, apresentando resultados comparáveis aos antioxidantes sintéticos utilizados. Houve interferência dos extratos de bagaço de uva na coloração da carne de frango cozida. Na análise de cor objetiva, os tratamentos com extrato de semente e casca de uvas Isabel e Niágara apresentaram-se mais escuros, menos avermelhados e com menor intensidade de cor amarela e, na análise subjetiva, as notas destes tratamentos, para o atributo alteração de cor, foram significativamente maiores (p<0,05) que as dos demais tratamentos. A coloração da carne de frango crua não foi afetada pela adição dos extratos. Através da análise sensorial, o extrato de bagaço de uva Isabel causou menor alteração no sabor e odor da carne de frango, apresentando resultados semelhantes aos antioxidantes sintéticos. Os resultados da análise microbiológica indicaram que as amostras de todos os tratamentos apresentaram-se dentro dos padrões estabelecidos pela legislação brasileira. A utilização de bagaço da indústria vinícola (semente e casca) como antioxidante natural, combinado com o uso da embalagem a vácuo e armazenamento congelado, pode ser considerada um método eficiente para retardar a oxidação lipídica de carne de frango processada, tanto crua, como cozida. Entretanto mais estudos devem ser conduzidos a fim de aprimorar a compatibilidade dos extratos ao produto, buscando minimizar suas interferências nas características sensoriais e organolépticas.Chicken meat, due to the high concentration of unsaturated fatty acids, is highly susceptible to lipid oxidation, which affects taste, aroma, colour and texture of foods, limiting its stability and shelf-life. Due to the possible toxicity of synthetic antioxidants and the current demand for healthier products, the use of natural antioxidants, such as grape seed and peel extract, is an alternative in the prevention of lipid oxidation in chicken meat, and allows the use of residues from wine and grape juice processing. Thus, the objective of this study was to evaluate grape pomace extracts (seeds and peels) of Isabel and Niagara varieties (Vitis labrusca L.) on the antioxidant activity in raw and cooked processed chicken meat. Four types of antioxidants were added to chicken meat: butylhydroxytoluene; commercial mixture of sodium erythorbate, citric acid and sugar; Isabel grape seed and peel extract; Niagara grape seed and peel extract; and the control, without antioxidant. The chicken meat was processed in the form of mini-burgers, vacuum packaged and stored under freezing (-18°C) for 9 months. The samples were characterized by determining the proximate composition. Every three months, the following analyses were carried out: pH, instrumental color, microbiological evaluation, lipid oxidation (value of thiobarbituric acid reactive substances - TBARS) and sensory analysis. No significant changes (p>0.05) in proximate composition and pH values were observed for raw and cooked samples, in none of the treatments. Both grape pomace extracts showed effect on inhibiting lipid oxidation in raw and cooked chicken meat, with results comparable to synthetic antioxidants used. There was interference from grape pomace extracts in the color of cooked chicken meat. In the objective color analysis, Isabel and Niagara grape seed and peel extract treatments were darker, less red and with less intense yellow color, and in the subjective analysis, the scores for these treatments, for attribute color alteration, were significantly higher (p<0.05) than the other treatments. The color of raw chicken meat was not affected by the addition of extracts. Through sensory evaluation, the Isabel grape pomace extract caused less change in taste and odour of chicken meat, with results similar to synthetic antioxidants. The results of microbiological analysis indicated that samples from all treatments were within the standards established by Brazilian legislation. The use of pomace from the wine industry (seeds and peels) as natural antioxidant, combined with the use of vacuum packaging and frozen storage, can be considered an effective method to retard lipid oxidation in processed chicken meat, both raw and cooked. However, further studies should be conducted in order to improve the compatibility of the extracts to the product, aiming to minimize its interference in the sensorial and organoleptic characteristics.
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Adavalli, Sharat Chandra. "Extrusion and physicochemical properties of soy-whey protein meat analog". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/6272.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 16, 2008) Includes bibliographical references.
45
Tse, Laam Angela. "Membrane Electrode Assembly (MEA) Design for Power Density Enhancement of Direct Methanol Fuel Cells (DMFCs)". Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11522.
Testo completoAbstract (sommario):
Micro-direct methanol fuel cells (micro-DMFC) can be the power supply solution for the next generation of handheld devices. The applications of the micro-DMFCs require them to have high compactness, high performance, light weight, and long life. The major goal of this research project is to enhance the volumetric power density of direct methanol fuel cells (DMFCs). A performance roadmap has been formulated and showed that patterning the planar membrane electrode assembly (MEA) to 2-D and 3-D corrugated manifolds can greatly increase the power generation with very modest overall volume increases. In this project, different manufacturing processes for patterning MEAs with corrugations have been investigated. A folding process was selected to form 2D triangular corrugations on MEAs for experimental validations of the performance prediction. The experimental results show that the volumetric power densities of the corrugated MEAs have improved by about 25% compared to the planar MEAs, which is lower than the expected performance enhancement. ABAQUS software was used to simulate the manufacturing process and identify the causes of deformations during manufacture. Experimental analysis methods like impedance analysis and 4 point-probes were used to quantify the performance loss and microstructure alteration during the forming process. A model was proposed to relate the expected performance of corrugated MEAs to manufacturing process variables. Finally, different stacking configurations and issues related to cell stacking for corrugated MEAs are also investigated.
46
Miller, Elizabeth Jane. "The correlation of magnetisation and microstructure in melt processed yttrium barium copper oxide". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294350.
Testo completo
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Shen, Yucai. "Processing and properties of melt processed polypropylene-clay and polylethylene terephthalate-clay nanocomposites". Thesis, Queen's University Belfast, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.546426.
Testo completo
48
Font, Morales Laura. "Melt inclusions from the Southwest Indian Ridge and Reykjanes Ridge : insights into melt extraction and magma chamber processes". Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274582.
Testo completo
49
Vlach, Jennifer L. "Meta-Parenting in Parents of Infants and Toddlers". Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc5566/.
Testo completoAbstract (sommario):
Meta-parenting, defined as parents thinking about their parenting, has been identified and is a new field of research. The purposes of this study were to add to the existing knowledge of meta-parenting and to compare the influences of gender, work status, and parenting experience on meta-parenting occurring in parents of infants and toddlers. Sixty parents participated either electronically or by completing a written survey and reported engaging from "sometimes" to "usually" in four domains of meta-parenting: anticipating, assessing, reflecting, and problem-solving. Gender, work status, and parenting experience did not significantly influence participants' meta-parenting scores. Parents were found to have a higher sense of satisfaction and overall sense of competence when they engaged in higher levels of meta-parenting.
50
Xu, Suxuan. "Fibrous soy protein meat analog from low moisture twin-screw extrusion". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/6035.
Testo completoAbstract (sommario):
Thesis (M.S.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 16, 2008) Includes bibliographical references.