Academic literature on the topic 'Central composite designs'

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Journal articles on the topic "Central composite designs"

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Iwundu, Mary Paschal. "Alternative Second-Order N-Point Spherical Response Surface Methodology Design and Their Efficiencies." International Journal of Statistics and Probability 5, no. 4 (June 11, 2016): 22. http://dx.doi.org/10.5539/ijsp.v5n4p22.

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The equiradial designs are studied as alternative second-order N-point spherical Response Surface Methodology designs in two variables, for design radius ρ = 1.0. These designs are seen comparable with the standard second-order response surface methodology designs, namely the Central Composite Designs. The D-efficiencies of the equiradial designs are evaluated with respect to the spherical Central Composite Designs. Furthermore, D-efficiencies of the equiradial designs are evaluated with respect to the D-optimal exact designs defined on the design regions of the Circumscribed Central Composite Design, the Inscribed Central Composite Design and the Face-centered Central Composite Design. The D-efficiency values reveal that the alternative second-order N-point spherical equiradial designs are better than the Inscribed Central Composite Design though inferior to the Circumscribed Central Composite Design with efficiency values less than 50% in all cases studied. Also, D-efficiency values reveal that the alternative second-order N-point spherical equiradial designs are better than the N-point D-optimal exact designs defined on the design region supported by the design points of the Inscribed Central Composite Design. However, the N-point spherical equiradial designs are inferior to the N-point D-optimal exact designs defined on the design region supported by the design points of the Circumscribed Central Composite Design and those of the Face-centered Central Composite Design, with worse cases with respect to the design region of the Circumscribed Central Composite Design.
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Jensen, D. R. "C432. Efficiency comparisons of central composite designs." Journal of Statistical Computation and Simulation 52, no. 2 (April 1995): 177–83. http://dx.doi.org/10.1080/00949659508811664.

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O. Ngonadi, Lilian, and Francis C. Eze. "Some Optimality Variations of Central Composite Designs." Academic Journal of Applied Mathematical Sciences, no. 54 (April 15, 2019): 32–42. http://dx.doi.org/10.32861/ajams.54.32.42.

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Some variations of central composite designs (CCD) under complete and partial replications of cube, axial and center points are studied using A, D and G optimality criteria. The results obtained suggest that complete replication of the cube, axial and center points are better than the partial replication of cube, axial and center points under the A and D optimality criteria studied while it varies under G optimality criterion. The partial replication of the cube, axial and center point for all the CCDs studied, the partial replicated cube point is D optimal but varies under A and G optimality criteria.
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O. Ngonadi, Lilian, and Francis C. Eze. "Some Optimality Variations of Central Composite Designs." Academic Journal of Applied Mathematical Sciences, no. 54 (April 15, 2019): 32–42. http://dx.doi.org/10.32861/ajams.54.32.42.

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Some variations of central composite designs (CCD) under complete and partial replications of cube, axial and center points are studied using A, D and G optimality criteria. The results obtained suggest that complete replication of the cube, axial and center points are better than the partial replication of cube, axial and center points under the A and D optimality criteria studied while it varies under G optimality criterion. The partial replication of the cube, axial and center point for all the CCDs studied, the partial replicated cube point is D optimal but varies under A and G optimality criteria.
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M. P., Iwundu,. "Construction of Modified Central Composite Designs for Non-standard Models." International Journal of Statistics and Probability 7, no. 5 (August 8, 2018): 95. http://dx.doi.org/10.5539/ijsp.v7n5p95.

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The use of loss function in studying the reduction in determinant of information matrix due to missing observations has effectively produced designs that are robust to missing observations. Modified central composite designs are constructed for non-standard models using principles of the loss function or equivalently first compound of (I ) matrix associated with hat matrix . Although central composite designs (CCDs) are reasonably robust to model mis-specifications, efficient designs with fewer design points are more economical. By classifying the losses due to missing design points in the CCD portions, where there are multiple losses associated with specified CCD portions, the design points having less influence may be deleted from the full CCD. This leads to a possible increase in design efficiency and offers alternative designs, similar in the structure of CCDs, for non-standard models.
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E.I., Jaja, Etuk E.H., Iwundu M.P., and Amos E. "Robustness of Central Composite Design and Modified Central Composite Design to a Missing Observation for Non-Standard Models." African Journal of Mathematics and Statistics Studies 4, no. 2 (May 11, 2021): 25–40. http://dx.doi.org/10.52589/ajmss-c5nkoi81.

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Missing observations in an experimental design may lead to ambiguity in decision making thereby bringing an experiment to disrepute. Robustness, therefore, enables a process, not to break down in the presence of missing observations. This work constructed a modified central composite design (MCCD) from a four-variable central composite design (CCD) augmented with four center points using the leverage of a hat-matrix. The robustness of the CCD and MCCD were assessed when a design point is missing at the factorial, axial, and center points of the experiment, for a non-standard model, using the loss criterion, D-optimality, D-efficiency, and relative D-efficiency. When the designs are complete the MCCD shows higher D-efficiency and D-optimality for the non-standard model when compared to the CCD. In the absence of an observation from any of the designs, the CCD is found to be a more robust and efficient design compared to the MCCD as it has overall lower loss values at all the factors levels.
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Palasota, John A., and Stanley N. Deming. "Central composite experimental designs: Applied to chemical systems." Journal of Chemical Education 69, no. 7 (July 1992): 560. http://dx.doi.org/10.1021/ed069p560.

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Mays, Darcy P., and Karen R. Schwartz. "Two-stage central composite designs with dispersion effects." Journal of Statistical Computation and Simulation 61, no. 3 (October 1998): 191–218. http://dx.doi.org/10.1080/00949659808811910.

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Sanchez, Susan M., and Paul J. Sanchez. "Very large fractional factorial and central composite designs." ACM Transactions on Modeling and Computer Simulation 15, no. 4 (October 2005): 362–77. http://dx.doi.org/10.1145/1113316.1113320.

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Ohaegbulem, Emmanuel, and Polycarp Chigbu. "An approach to measuring rotatability in central composite designs." International Journal of Advanced Statistics and Probability 3, no. 2 (May 31, 2015): 126. http://dx.doi.org/10.14419/ijasp.v3i2.4657.

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<p>An approach to measure design rotatability and a measure, that quantifies the percentage of rotatability (from 0 to 100) in the central composite designs are introduced. This new approach is quite different from the ones provided by previous authors which assessed design rotatability by the viewing of tediously obtained contour diagrams. This new approach has not practical limitations, and the measure is very easy to compute. Some examples were used to express this approach.</p>
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Dissertations / Theses on the topic "Central composite designs"

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Wang, Li. "Recommendations for Design Parameters for Central Composite Designs with Restricted Randomization." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28794.

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In response surface methodology, the central composite design is the most popular choice for fitting a second order model. The choice of the distance for the axial runs, alpha, in a central composite design is very crucial to the performance of the design. In the literature, there are plenty of discussions and recommendations for the choice of alpha, among which a rotatable alpha and an orthogonal blocking alpha receive the greatest attention. Box and Hunter (1957) discuss and calculate the values for alpha that achieve rotatability, which is a way to stabilize prediction variance of the design. They also give the values for alpha that make the design orthogonally blocked, where the estimates of the model coefficients remain the same even when the block effects are added to the model. In the last ten years, people have begun to realize the importance of a split-plot structure in industrial experiments. Constructing response surface designs with a split-plot structure is a hot research area now. In this dissertation, Box and Hunters' choice of alpha for rotatablity and orthogonal blocking is extended to central composite designs with a split-plot structure. By assigning different values to the axial run distances of the whole plot factors and the subplot factors, we propose two-strata rotatable splitplot central composite designs and orthogonally blocked split-plot central composite designs. Since the construction of the two-strata rotatable split-plot central composite design involves an unknown variance components ratio d, we further study the robustness of the two-strata rotatability on d through simulation. Our goal is to provide practical recommendations for the value of the design parameter alpha based on the philosophy of traditional response surface methodology.
Ph. D.
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Liang, Li. "Graphical Tools, Incorporating Cost and Optimizing Central Composite Designs for Split-Plot Response Surface Methodology Experiments." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/26768.

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In many industrial experiments, completely randomized designs (CRDs) are impractical due to restrictions on randomization, or the existence of one or more hard-to-change factors. Under these situations, split-plot experiments are more realistic. The two separate randomizations in split-plot experiments lead to different error structure from in CRDs, and hence this affects not only response modeling but also the choice of design. In this dissertation, two graphical tools, three-dimensional variance dispersion graphs (3-D VDGs) and fractions of design space (FDS) plots are adapted for split-plot designs (SPDs). They are used for examining and comparing different variations of central composite designs (CCDs) with standard, V- and G-optimal factorial levels. The graphical tools are shown to be informative for evaluating and developing strategies for improving the prediction performance of SPDs. The overall cost of a SPD involves two types of experiment units, and often each individual whole plot is more expensive than individual subplot and measurement. Therefore, considering only the total number of observations is likely not the best way to reflect the cost of split-plot experiments. In this dissertation, cost formulation involving the weighted sum of the number of whole plots and the total number of observations is discussed and the three cost adjusted optimality criteria are proposed. The effects of considering different cost scenarios on the choice of design are shown in two examples. Often in practice it is difficult for the experimenter to select only one aspect to find the optimal design. A realistic strategy is to select a design with good balance for multiple estimation and prediction criteria. Variations of the CCDs with the best cost-adjusted performance for estimation and prediction are studied for the combination of D-, G- and V-optimality criteria and each individual criterion.
Ph. D.
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Mendonça, Layanne Andrade. "Desempenho do delineamento composto central em experimentos com alto coeficiente de variação." Universidade Federal de Viçosa, 2012. http://locus.ufv.br/handle/123456789/4052.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The present work had the purpose of evaluating the performance of the rotational central composite design (RCCD) in relation to the estimated response surface parameters, under conditions of simulated experimental errors that provide high coefficients of variation. The big impulse of the response methodology was given by Box and Wilson (1951), who developed methods of process optimization in industrial researches. Within these methods, the RCCD may be mentioned as an economic design for the response surface, due to the reduced number of level combinations in the studied factors, when compared to the full factorial. However, it is known that these designs are efficient where experimental mistakes are usually small and the conditions of the experiment are easily controlled. However, given the reduced number of tests by the RCCD, it has become important to verify its potential in designing treatments to adjust response surfaces on experiments related to agrarian sciences, that present, naturally, larger random error. For such, the treatment designs, full factorial and rotational central composite have been used to plan the combinations between the coded levels of two factors (A and B). A second-order model has been established for two factors A and B without interaction among them, named true response surface. A full 5x5 factorial has been established, with the combinations between the coded levels of factors A and B and 40 repetitions per treatment. In total, 1000 experimental units have been built. Afterwards, 100 simulations have been made for the experimental errors ε present in the experiment under normal conditions with average zero and variations σε2. The parameter σε has been specified in 32, 48, 64 and 80, to provide the residual coefficients of variation (CV) equal to 25, 37, 50 and 60 %. The choice of these coefficients of variation has been made in order to include the classifications created by Ferreira (1991), quoted by Silva et al. (2011), and Pimentel Gomes (1985) for the agrarian areas. The observed values of Y have been obtained from the sum of the true values of Y ( ) obtained from the true response surface, with residuals ( ), generated by the simulation. In each type of design (RCCD and full factorial), three, six, nine and twelve repetitions per treatment have been established. According to the combinations between the types of treatment, coefficients of variation and number of repetitions per treatment, 100 adjustments of the response surface have been realized, from which the averages of the coefficient of determination, the average distances between the true and the estimated critical point (CPD) and between the coefficients of variation estimated and simulated (CVD), besides the success percentage and confidence interval of each parameter and the percentage of success from the response surface. Afterwards, a regression of these measures as been made, evaluated based on the design, coefficient of variation and number of repetitions per treatment. The superiority of performance of the full factorial in relation to the RCCD increase in relation to the increase of the CV and the reducing of the number of repetitions per treatment. The RCCD has been recommended under more controlled experimental conditions, for being a more economic treatment design. However, knowing the difficulty of controlling the random error on experiments for the agrarian areas, in experiments of this nature the full factorial or the RCCD were recommended with a larger number of repetitions per treatment. It has also been concluded that the increase of the CV prejudices the adjustment quality of the full factorial and mainly of the RCCD and this prejudice can be compensated with the increase in the number of repetitions per treatment. It has been seen that the adjustment quality provided by the treatment design does not depend only of their quantity, but mostly on the sufficient amount of experimental units to provide proper estimates of the effects of the known and unknown factors.
Esse trabalho teve como objetivo avaliar o desempenho do delineamento composto central rotacional (DCCR) em relação às estimativas dos parâmetros da superfície de resposta estimada, sob condições de erros experimentais simulados que proporcionam altos coeficientes de variação. O grande impulso da metodologia de resposta foi dado por Box e Wilson (1951), que desenvolveram métodos de otimização de processos em pesquisas industriais. Dentre esses métodos, pode-se citar o DCCR como um delineamento econômico para a superfície de resposta, devido ao número reduzido de combinações entre os níveis dos fatores estudados, quando comparado ao fatorial completo. No entanto, sabe-se que estes delineamentos são eficientes onde normalmente os erros experimentais são pequenos e as condições do experimento são mais facilmente controláveis. Portanto, dada a economia do número de ensaios pelo DCCR, tornou-se importante verificar o seu potencial em delinear tratamentos visando o ajuste de superfícies de respostas para experimentos ligados às ciências agrárias, que apresentam, naturalmente, maiores erros aleatórios. Para tanto, os delineamentos de tratamentos, fatorial completo e composto central rotacional foram utilizados para planejar as combinações entre os níveis codificados de dois fatores (A e B). Foi estabelecido um modelo de segunda ordem para dois fatores A e B sem interação entre eles, denominada de superfície de resposta verdadeira. Foi estabelecido um fatorial completo 5x5, com as combinações entre os níveis codificados dos fatores A e B e com 40 repetições por tratamento. No total, foram constituídas 1000 unidades experimentais. Posteriormente, foram feitas 100 simulações para os erros experimentais presentes no experimento sob distribuição normal com média zero e variância σε2. O parâmetro σε foi especificado em 32, 48, 64 e 80, para fornecer os coeficientes de variação residuais (CV) iguais a 25, 37, 50 e 62 %. A escolha de tais coeficientes de variação foi feita de modo a abranger as classificações criadas por Ferreira (1991), citado por Silva et al. (2011), e Pimentel Gomes (1985) para as áreas agrárias. Os valores observados de Y foram obtidos a partir da soma dos valores verdadeiros de Y ( ) obtidos a partir da superfície de resposta verdadeira, com os resíduos , gerados pela simulação. Em cada tipo de delineamento (DCCR e fatorial completo), foram estabelecidas três, seis, nove e doze repetições por tratamento. De acordo com as combinações entre os tipos de delineamentos, coeficientes de variação e número de repetições por tratamento, foram realizados 100 ajustes da superfície de resposta dos quais foram obtidas as médias do coeficiente de determinação, EQM, a distância média entre o ponto crítico verdadeiro e o estimado (DPC) e a diferença média entre os coeficientes de variação estimados e simulados (DCV), além da porcentagem de acerto e intervalo de confiança de cada parâmetro e a porcentagem de acerto da superfície de resposta. Posteriormente foi feita uma regressão dessas medidas avaliadas em função do delineamento, coeficiente de variação e número de repetições por tratamento. A superioridade do desempenho do fatorial completo em relação DCCR aumentou em função do aumento do CV e da diminuição do número de repetições por tratamento. Recomendou-se o DCCR sob condições experimentais mais bem controladas, por ser um delineamento de tratamento mais econômico. No entanto, sabendo do difícil controle do erro aleatório em experimentos das áreas agrárias, em experimentos dessa natureza recomendou-se o fatorial completo ou o DCCR com um número maior de repetições por tratamento. Conclui-se também que o aumento do CV prejudica a qualidade de ajuste do fatorial completo e principalmente a do DCCR e esse prejuízo pode ser compensado com o aumento do número de repetições por tratamento. Percebeu-se que a qualidade de ajuste proporcionada pelo delineamento de tratamento não depende só da quantidade dos mesmos, mas principalmente da quantidade de unidades experimentais suficientes para proporcionar estimativas adequadas dos efeitos dos fatores conhecidos e desconhecidos.
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Nogueira, Danielle Pires. "Estudo da obtenção de açúcares redutores totais a partir do bagaço de laranja (Citrus sinenses) por hidrólises ácida diluída e enzimática." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6084.

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Due to the recent research for new fuels from renewable sources ethanol has been gaining momentum, because it can be produced from diverse raw materials, such as agro-industrial residues. The objective with this work was to study the production of reducing sugar by dilute acid, and enzymatic hydrolysis of the orange bagasse from juice industry. The orange bagasse was collected, cut into pieces, and crushed. Granulometry, and the contents of moisture, ashes, holocellulose, cellulose, hemicelulose, soluble and insoluble lignin were determined. The pre-treatment was done with calcium hydroxide following what was previously tested by Silva et al. (2013). A pre-test of the enzymes combination was done using 2 g of pre-treated biomass, in dry base, using 3 FPU/mL of cellulase, and 0 U/g and 3 U/g of xylanase. For the hydrolysis two central composite factorial 2³ designs were done, with the answer in total reducing sugars (ART). For the dilute acid hydrolysis the factors were HCl concentration, temperature, and time, and for the enzymatic the concentrations of cellulase and xylanase and time. The granulometry showed that 47.75% of the biomass with diameter over 0.833 mm, 32.84% of the biomass with an average diameter of 0.564 mm, and 19.41% of the biomass with diameter under 0.295 mm. The moisture content prior to drying was 84.69% and 7.38%, the ashes content was 3.79%. The cellulose content was 22.90% and the hemicellulose was 3.39%. The lignin content was 9.90%. The reducing sugar results for the acid hydrolysis varied from 9.32±0.68 mg ART per g of biomass to 30.15±0.31 mg ART per g biomass, the most significant factor was temperature, and the least was time. It was not possible to find the optimum region with the studied factors. The reducing sugar results for the enzymatic hydrolysis varied from 75.33±3.82 mg ART per g biomass to 99.66±0.62 mg ART per g biomass, the most significant factor was the cellulase concentration, and the least significant the xylanase concentration. The studied factors did not show the optimum region to maximize the reducing sugars content. The enzymatic hydrolysis produced larger concentrations of reducing sugars than the acid hydrolysis.
Frente as recentes buscas por novos combustíveis de fontes renováveis o etanol de segunda geração tem ganhado força, por poder ser produzido a partir de diversas matérias primas lignocelulósicas, como os resíduos agroindustriais. Objetivou-se com este trabalho estudar a geração de açúcares redutores por hidrólises ácida diluída e enzimática do bagaço de laranja proveniente da indústria de suco. O bagaço de laranja foi coletado, cortado, seco e moído. Granulometria, umidade, cinzas, concentrações de holocelulose, celulose, hemicelulose e lignina solúvel e insolúvel foram determinadas. O pré-tratamento foi realizado com hidróxido de cálcio de acordo com o previamente testado por Silva et al. (2013). Foi realizado um pré-teste da combinação das enzimas. Para as hidrólises foram feitos dois planejamentos fatoriais do tipo composto central 2³, com resposta em açúcares redutores totais (ART). Para a hidrólise ácida diluída os fatores estudados foram concentração de HCl, temperatura e tempo de hidrólise, na enzimática as concentrações de celulase e hemicelulase e o tempo. Na análise granulométrica encontrou-se 47,75% da biomassa com diâmetro superior a 0,833 mm, 32,84% de biomassa com diâmetro médio de 0,564 mm e 19,41% com diâmetro inferior a 0,295 mm. A umidade da biomassa antes da secagem foi de 84,69%, depois da secagem de 7,38% e as cinzas 3,79%. O conteúdo de celulose foi de 22,90% e o de hemicelulose 3,39%. O conteúdo de lignina foi de 9,90%. Houve uma perda de massa média de 30,03% no pré-tratamento. O pré-teste indicou um efeito positivo na combinação das enzimas para geração de açúcares redutores. Os resultados de açúcares redutores da hidrólise ácida variaram de 9,32±0,68 mg ART por g de biomassa a 30,15±0,31 mg ART por g biomassa, o fator mais significativo foi a temperatura e o menos o tempo, não foi possível encontrar a região ótima com os fatores estudados. Os resultados de açúcares redutores da hidrólise enzimática variaram de 75,33±3,82 mg ART por g biomassa a 99,66±0,62 mg ART por g biomassa, o fator mais significativo foi a concentração de celulase e o menos a concentração de xilanase. Com os fatores estudados não foi possível encontrar a região ótima de geração de açúcares redutores. A hidrólise enzimática gerou maiores concentrações de açúcares redutores que a hidrólise ácida.
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Chan, Joyce M. Eng Massachusetts Institute of Technology. "A central composite design to investigate antibody fragment production by Pichia pastoris." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33872.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Biological Engineering Division, 2005.
Includes bibliographical references (p. 77-80).
This study aims to investigate the relationships between growth parameters (agitation, glycerol concentration, salt concentration) and responses (biomass, growth rate, protein expression), by a 3-factor-3-level central composite factorial design. This experimental design involved running shake flask culture at 15 different experimental conditions with duplicates. Optical density (OD600), dry cell weight (DCW), and BCA Protein Assays were done on each experiment. Mathematical models in terms of these parameters' effects and their interactions were proposed for each of the responses. The significance of each effect and interaction, as well as the goodness-of-fit of mathematical models to data were examined by analysis of variance. It was found that biomass (with R²Adj=0.951) is a strong function of glycerol concentration (higher glycerol concentration leads to higher biomass), but it varies much less with agitation, and it is completely independent of salt concentration. Growth rate (R²Adj=0.901), however, varies strongly with agitation and salt concentration, but much more weakly with glycerol concentration. Protein production has a low R²Adj value of 0.746, implying that higher-order terms, e.g. x₁² and x₂², should be tested for significance in the model.
(cont.) Collected data were fitted to the proposed models by response surface regression, after which surface and contour plots of responses were generated to identify trends in them. High agitation (300 rpm in shaker) gave rise to both highest biomass and growth rate. In addition, biomass at high glycerol concentration (3% v/v) was almost twice as much as biomass at low glycerol concentration (1% v/v) at high agitation rate (19 g/L compared to 11 g/L). At the same agitation rate, growth rate shows the largest increase of 20.5% with increasing salt concentration from 0.7% to 2.1%. Protein production reached maximum of 7.3 mg/mL at medium agitation rate (250 rpm), high salt and glycerol concentrations.
by Joyce Chan.
M.Eng.
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Alcantara, Michael Steinhorst. "Avaliação de biodigestor tubular na degradação anaeróbia de cama de frango de corte." Universidade Estadual do Oeste do Parana, 2012. http://tede.unioeste.br:8080/tede/handle/tede/399.

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In the twenty-first century, the broiler production has increased in the world and continues increasing due to the high consumption of this meat. The broiler litter is the largest amount of waste generated in poultry production. It is also characterized by its high concentration of organic matter. The broiler production integrated system defines a radius around it to settle down poultry farms in order to reduce costs. It has also increased the concentration of broiler litter in the producing regions and demanded waste treatment. So, the anaerobic digestion has come as an alternative treatment with high organic load removal. Thus, this trial aimed at evaluating the treatment capacity of broiler litter by anaerobic digestion into tubular biodigester with a semi-continuous flow. The applied treatments varied both the amount of added total volatile solids, from 2.93 to 3.72%, as well as the hydraulic retention time, from 11.60 to 28.40 days. The digesters were maintained at 27 ºC and considered stabilized when the removal efficiency of total solids, total volatile solids and chemical oxygen demand were according to the statistical quality control. Once stabilized, the 11 digesters of 0.6 m per 0.15 m (length per diameter) were evaluated for removal of solids and chemical oxygen demand with statistical quality control and design composite central rotational in a factorial design (22), at two levels (-1, 1), plus the axial points (-α, α) and the central point. The analysis of statistical quality control showed that the treatment with 3.32% added total volatile solids and 20 days of hydraulic retention time removed the highest amount of total solids (64.37%) and total volatile solids (72.38%), while the removal values of chemical oxygen demand were similar in all treatments, around 80%. Significant statistical models were registered with the central composite rotational design to remove total solids and for chemical oxygen demand.
No século XXI, a produção de frangos de corte ganhou espaço no mercado e continua crescendo, devido ao alto consumo da carne. A cama de frango é o resíduo gerado em maior quantidade na produção de frangos e caracteriza-se pela elevada concentração de matéria orgânica. O sistema de produção de frango de corte das empresas integradoras delimita um raio ao seu redor para implantação de aviários, visando à redução de custos, além de ocasionar a concentração de cama de frango nas regiões produtoras e gerar a necessidade de tratar o resíduo. A digestão anaeróbia é uma alternativa de tratamento, com alta remoção de carga orgânica. Logo, o objetivo deste trabalho foi avaliar a capacidade de tratamento da digestão anaeróbia da cama de frango em biodigestor tubular de fluxo semicontínuo. Os tratamentos aplicados variaram tanto a quantidade de sólidos totais voláteis adicionados, de 2,93 a 3,72% como o tempo de detenção hidráulica, de 11,60 a 28,40 dias. Os biodigestores foram mantidos a 27 ºC e considerados estabilizados quando as eficiências de remoção de sólidos totais, sólidos totais voláteis e demanda química de oxigênio encontraram-se dentro do controle estatístico de qualidade. Depois de estabilizados, os onze biodigestores de 0,60 m por 0,15 m (comprimento x diâmetro) foram avaliados quanto à remoção de sólidos e à demanda química de oxigênio com o controle estatístico de qualidade. O delineamento composto central rotacional foi em esquema fatorial (22), em dois níveis (1, +1), mais os pontos axiais (-α, +α) e o ponto central. A análise do controle estatístico de qualidade mostrou que o tratamento com 3,32% de sólidos totais voláteis adicionados e 20 dias de tempo de detenção hidráulica foi o que mais se destacou na remoção de sólidos totais (64,37%) e sólidos totais voláteis (72,38%) e os valores de remoção de demanda química de oxigênio foram próximos em todos os tratamentos, em torno de 80%. Com o delineamento composto central rotacional, foram verificados modelos estatísticos significativos para a remoção de sólidos totais e demanda química de oxigênio.
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7

Bourscheid, Cristiane. "OTIMIZAÇÃO DO PROCESSO DE HIDRÓLISE ENZIMÁTICA DE COPRODUTO DA DESOSSA DE FRANGO E APLICAÇÃO DO HIDROLISADO EM HAMBÚRGUER." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2015. http://tede2.uepg.br/jspui/handle/prefix/645.

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The chicken slaughterhouse generate co-products during slaughter, for example, feathers, bones, blood and guts, usually intended for animal feed with low added value. In bone part of the meat remains bound even after deboning and is a good source of substrate for the enzymatic hydrolysis. The protein hydrolysates may be applied as a nutritional supplement in foods. Given this context, the objective was to optimize the enzymatic hydrolysis process for obtaining protein hydrolyzate coproduct of chicken bones (Gallus gallus domesticus) and the addition of the hydrolyzate as a protein supplement in burger. The co-product selected to carry out the work was thigh and drumstick bone from the chicken bones in a slaughterhouse. The study was conducted in two stages. In the first one a central composite design (CCRD), a total of 17 tests was adopted to evaluate the influence of temperature, enzyme: substrate ratio and time on the degree of hydrolysis. Following the statistical optimization was performed to obtain the best conditions of enzymatic hydrolysis of co-product of chicken bones. The co-product of chicken bones and the optimized protein hydrolyzate were characterized in terms of chemical composition, total amino acids and pattern. In the second step, the hydrolyzate was added as a protein supplement in poultry burger, where two formulations were prepared, Hamburger control (no addition of protein hydrolyzate) and hamburger with hydrolyzed (with addition of 8% protein hydrolyzate). The burgers were characterized in terms of physical-chemical, microbiological and sensory analysis. The optimum conditions for the enzymatic hydrolysis were temperature (T) of 50 ° C, enzyme: substrate ratio (E:S) from 4.96% to time (t) of 110.16 minutes under these conditions the degree of hydrolysis was 24, 0.22 ± 21%. The protein hydrolyzate has the potential to supplementation in food, it is good source of essential amino acids, meeting the recommendations established by FAO / WHO, except for leucine, phenylalanine, and valine, and had a higher concentration of protein fractions from 14.437 kDa and 3,496 kDa. The results obtained for microbiological analysis and physical-chemical analysis of the burger control and burger with hydrolyzed, are in accordance with the respective standards set by law. The burger with hydrolyzate showed 1.02% more protein than the burger control, giving a protein supplementation to the product developed. In the sensorial analysis for flavor attribute evaluators preferred the burger with protein hydrolyzate. The burger with protein hydrolyzate and the burger control achieved 84.2% and 81.8% of general acceptance, respectively. The intention to buy for the burger with added protein hydrolyzate was 76.4% and for the burger control was 67%. In this light, the protein hydrolyzate obtained from chicken bones of the co-product is an alternative to supplementation in foods, as well as add value to the co-product of chicken dessosa and increase the competitiveness of slaughterhouse.
Os frigoríficos de frango geram coprodutos durante o abate, por exemplo, penas, ossos, sangue e vísceras, geralmente, destinados para ração animal com baixo valor agregado. Uma parte de carne permanece aderida aos ossos, mesmo após a desossa, sendo uma boa fonte de substrato para a hidrólise enzimática. Os hidrolisados proteicos podem ser aplicados como suplemento nutricional em alimentos. Diante desse contexto, o objetivo do trabalho foi otimizar o processo de hidrólise enzimática para obtenção de hidrolisado proteico de coproduto da desossa de frango (Gallus gallus domesticus) e a adição do hidrolisado como suplemento proteico em hambúrguer. O coproduto selecionado para realização do trabalho foi osso de coxa e sobrecoxa proveniente da desossa de frango em frigorífico. O trabalho foi realizado em duas etapas. Na primeira um delineamento composto central rotacional (DCCR), totalizando 17 ensaios foi adotado para avaliar a influência da temperatura, relação enzima:substrato e tempo sobre o grau de hidrólise. Na sequência, foi realizada a otimização estatística para obter as melhores condições da hidrólise enzimática. O coproduto da desossa de frango e o hidrolisado proteico otimizado foram caracterizados em termos de composição centesimal, aminoácidos totais e perfil eletroforético. Na segunda etapa, o hidrolisado foi adicionado como suplemento proteico em hambúrguer de frango. Foram elaboradas duas formulações, hambúrguer controle (sem adição de hidrolisado proteico) e hambúrguer com hidrolisado (com adição de 8% de hidrolisado proteico). Os hambúrgueres foram caracterizados em termos de análises físico-químicas, análises microbiológicas e análise sensorial. As condições ótimas para a hidrólise enzimática foram temperatura (T) de 50ºC, relação enzima:substrato (E:S) de 4,96% e tempo (t) de 110,16 minutos, nessas condições o grau de hidrólise foi de 24,21% ±0,22. O hidrolisado proteico apresentou potencial para suplementação em alimentos, pois é boa fonte de aminoácidos essenciais, atendendo as recomendações estabelecidas pela FAO/WHO, exceto para leucina, fenilalanina e valina, bem como apresentou maior concentração de frações proteicas entre 14,437 kDa e 3,496 kDa. Os resultados obtidos para a análise microbiológica e análises físico-químicas do hambúrguer controle e do hambúrguer com hidrolisado, estão de acordo com os respectivos padrões estabelecidos pela legislação vigente. O hambúrguer com hidrolisado apresentou 6% mais proteína do que o hambúrguer controle, conferindo uma suplementação proteica ao produto desenvolvido. Em relação à análise sensorial para o atributo sabor, os avaliadores preferiram o hambúrguer com hidrolisado proteico. O hambúrguer com hidrolisado proteico e o hambúrguer controle obtiveram 84,2% e 81,8% de aceitação geral, respectivamente. A intenção de compra para o hambúrguer com adição de hidrolisado proteico foi de 76,4% e para o hambúrguer controle foi de 67%. Diante do exposto, o hidrolisado proteico obtido a partir de coproduto da desossa de frango é uma alternativa para a suplementação em alimentos, além de agregar valor ao coproduto da dessosa de frango e aumentar a competitividade dos frigoríficos.
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8

Silva, Ana LÃvia Brasil. "Optimization of levels of seaweed japonica saccharine and chenopodium quinoa wild in developing cereal bar." Universidade Federal do CearÃ, 2015. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17234.

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CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior
Seaweed japonica saccharine, popularly known as "Kombu" is a food rich in protein, fiber and micronutrients. This algae has antioxidant properties, anti-viral, anti-tumor, anti-inflammatory and hypoglycemic. Quinoa (Chenopodium quinoa Willd) is considered a pseudocereal whose main characteristic is the quality of its protein and is recognized by the World Health Organization (WHO) as an ideal food for its nutritional composition is higher than most cereals. The addition of these two ingredients in salt cereal bar formulation can add greater nutritional value to this product, which has shown an increasing consumption in recent years. The study aimed to prepare savory cereal bars added the saccharine japonica algae in different concentrations (2, 4, 6, 8, 10%) and quinoa (1, 2, 3, 4, and 5%), through the use of design central composite (DCC). One of the formulations of the cereal bars was selected to study storage stability, with respect to acidity and moisture and microbiological analysis, and sensory parameters at times 0, 30, 60 and 90 days. In the development of cereal bars, the formulations examined had ash contents of 4.46% to 8.04% (Formulations 9 and 4, respectively), fat 2.8% to 4.61% (Formulations 3 and 5, respectively), and protein 14.2% to 19.19% (Formulations 1 and 10, respectively). The Maoria bars showed sensory acceptance corresponding to "like slightly to like a lot," and had satisfactory results for microbiological analyzes. The formulation 5, added with 2% and 3% seaweed quinoa, achieved the best results concerning the nutritional and sensory quality, thus has been selected for the study of storage stability. The moisture and acidity remained stable after 90 days of storage, similar results were observed for the microbiological quality. According to sesorial analysis, the number 5 cereal bar is framed in sensory acceptance zone in category "like moderately" to "enjoyed". Therefore, it was concluded that the developed cereal bars can become an option for many types of diet or for those seeking a healthier lifestyle, it presented high protein and low fat, as well as showing good sensory acceptance.
A alga Saccharina japonica, conhecida popularmente como âKombuâ à um alimento rico em proteÃna, fibra e micronutrientes. Esta alga apresenta propriedade antioxidante, antiviral, antitumoral, anti-inflamatÃria e hipoglicÃmica. A quinoa (Chenopodium quinoa Willd) à considerada um pseudocereal que tem como principal caracterÃstica a qualidade de sua proteÃna, sendo reconhecida pela OrganizaÃÃo Mundial de SaÃde (OMS) como um alimento ideal, por sua composiÃÃo nutricional ser superior à maioria dos cereais. A adiÃÃo desses dois ingredientes na formulaÃÃo de barra de cereais salgada poderà agregar um maior valor nutricional a esse produto, que vem apresentando um crescente consumo nos Ãltimos anos. O trabalho teve como objetivo elaborar barras de cereais salgadas adicionadas da alga Saccharina japÃnica em diferentes concentraÃÃes (2, 4, 6, 8, 10%) e de quinoa (1, 2, 3, 4, e 5%), por meio do uso do Delineamento Composto Central Rotacional (DCCR). Uma das formulaÃÃes das barras de cereal foi selecionada para o estudo de estabilidade ao armazenamento, quanto Ãs anÃlises de acidez e umidade e aos parÃmetros microbiolÃgicos e sensoriais, nos tempos 0, 30, 60 e 90 dias. No desenvolvimento das barras de cereal, as formulaÃÃes analisadas apresentaram teores de cinzas de 4,46% a 8,04% (FormulaÃÃes 9 e 4, respectivamente), gordura de 2,8% a 4,61% (FormulaÃÃes 5 e 3, respectivamente), e proteÃna de 14,2% a 19,19% (FormulaÃÃes 1 e 10, respectivamente). A maoria das barras apresentou aceitaÃÃo sensorial correspondente a âgostei ligeiramente a gostei muitoâ, bem como tiveram resultados satisfatÃrios para as anÃlises microbiolÃgicas. A formulaÃÃo 5, adicionada com 2% de alga e 3% de quinoa, obteve os melhores resultados referentes à qualidade nutricional e sensorial, desta maneira foi selecionada para o estudo de estabilidade ao armazenamento. Os teores de umidade e de acidez mantiveram-se estÃveis apÃs 90 dias de estocagem, resultado semelhante foi observado para a qualidade microbiolÃgica. De acordo com as anÃlises sesorial, a barra de cereal de nÃmero 5 se enquadrou na zona de aceitaÃÃo sensorial na categoria âgostei moderadamenteâ a âgostei muitoâ. Portanto, concluiu-se que as barras de cereais desenvolvidas podem se tornar uma opÃÃo para diversos tipos de dieta ou para quem procura uma vida saudÃvel, pois apresentou elevado teor de proteÃnas e baixo teor de gordura, alÃm de apresentar boa aceitaÃÃo sensorial.
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9

Martinez, Fabio Andres Castillo. "Produção de bacteriocina por Bifidobacterium lactis a partir de leite desnatado." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/9/9135/tde-16012014-134005/.

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Existe um número muito limitado de estudos referentes à produção de componentes antimicrobianos ou bacteriocinas produzidas por espécies de bifidobactérias. Nesse âmbito, o objetivo deste trabalho foi avaliar a produção de bifidobacteriocina em leite desnatado (LD). Para tanto, o estudo foi dividido em três etapas. A primeira etapa constituiu na preparação dos meios de cultura Man, Rogosa e Sharpe (MRS), Bifidus Selective Medium (BSM) e LD suplementado com 1% (p/v) de Tween 80 (T80), Inulina (I) ou Extrato de levedura (YE). Nesta etapa, os processos fermentativos foram conduzidos em shaker, nas condições: 50 rpm/37ºC/48h. Foram realizadas análises de pH, concentração de açúcares e ácidos, crescimento celular e determinação da atividade da bifidobacteriocina pelo método de difusão em ágar contra L. monocytogenes. Na segunda etapa, e baseado nos resultados obtidos, foi desenhado um delineamento composto central (CCD) construído a partir dos seguintes parâmetros: temperatura (34, 37, 40 °C) e concentração de YE (0,5; 1,0; 1,5 g/L). Na terceira etapa do trabalho, foram realizados os cultivos em biorreator de 2 L, contendo 10% de leite desnatado, nas seguintes condições: 200 rpm, 36°C, 2,0 g/L de YE, 48h de incubação em anaerobiose. Obteve-se em LD suplementado com YE (1%), combinado ao método de difusão em placa modificado (prévia refrigeração das placas por 12h), contra L. monocytogenes (2130 AU/mL), com uma fase exponencial de 24h, µm de 0,604/h. A otimização feita através do CCD permitiu atingir níveis de atividade de 3.000 AU/mL a 3.100 AU/mL (ensaios 7, 11 e 14, blocos 3 e 1) contra L. monocytogenes, em condições ótimas de crescimento de YE: 2,0 g/L1 e T°C: 36°C. A análise de regressão mostrou ser estatisticamente significativa a relação entre as variáveis: \"concentração de \"YE e temperatura\". Os resultados indicaram que o leite desnatado é um meio adequado para produção de bifidobacteriocina.
There are few publications that have been reported about bacteriocin production by Bifidobacterium species. Therefore, the aim of this work was measure bacteriocin production in skim milk by B. lactis. Consequently, this work was divided in three stages. First, MRS, BSM and LD medium were tested with additives (Tween 80 (T80), Inuline (I) or Yeast extract (YE)) for bacteriocin production and cellular growth. Fermentation processes were conducted in shaker under specific conditions: 50 rpm/37ºC/48h. pH; sugars; acids; biomass, and bacteriocin activity against L. monocytogenes, L. plantarum, E. coli, L. sakei e S. aureus strains were analyzed . In the second stage, based on the obtained results, a central composite design (CCD) was created using the parameters: temperature (34, 37, 40 ºC), and concentration of YE (0.5, 1.0, 1.5 g/L). After, the activity was measured by two methods of plates pre-diffusion (cooling and addition of Tween 20). Third step consisted of 2 L bioreactor cultivations containing 10% skim milk diluted in 1.5 L of water (6.5 pH), under 200 rpm, 36 ºC, 2.0 g/L of YE, 48h, under anaerobic condition. Finally, the cultures supplemented with LD and YE (1%) with a modified plate diffusion method (cooling plates for 12 h) showed bacteriocin activity against L. monocytogenes (2130 AU/mL) with an exponential phase of 24 h, µm of 0.604/h. The optimization performed using CCD resulted in a higher level of activity 3000 AU/mL to 3100 AU/mL mL (Run 7, 11 and 14, blocks 3 and 1) against L. monocytogenes, also with ideal growth conditions of YE: 2,0 g/L1 and T °C: 36 °C. The pH value varied between 6.4 and 4.0. Concentration of produced acid lactic varied from 3.03 to 4.72 g/L and biomass concentration from 3.4 to 11.1 Lg UFC/mL. Regression analysis was significant to the variables: YE concentration and temperature. Results indicated that skim milk is a proper medium for \"Bifidobacteriocin\" production.
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10

Silva, Ana Lívia Brasil. "Otimização dos teores de alga Saccharina japônica E Chenopodium quinoa Wild no desenvolvimento de barra de cereais." reponame:Repositório Institucional da UFC, 2015. http://www.repositorio.ufc.br/handle/riufc/18192.

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SILVA, Ana Lívia Brasil. Otimização dos teores de alga Saccharina japônica E Chenopodium quinoa Wild no desenvolvimento de barra de cereais. 2015. 67 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2015
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Seaweed japonica saccharine, popularly known as "Kombu" is a food rich in protein, fiber and micronutrients. This algae has antioxidant properties, anti-viral, anti-tumor, anti-inflammatory and hypoglycemic. Quinoa (Chenopodium quinoa Willd) is considered a pseudocereal whose main characteristic is the quality of its protein and is recognized by the World Health Organization (WHO) as an ideal food for its nutritional composition is higher than most cereals. The addition of these two ingredients in salt cereal bar formulation can add greater nutritional value to this product, which has shown an increasing consumption in recent years. The study aimed to prepare savory cereal bars added the saccharine japonica algae in different concentrations (2, 4, 6, 8, 10%) and quinoa (1, 2, 3, 4, and 5%), through the use of design central composite (DCC). One of the formulations of the cereal bars was selected to study storage stability, with respect to acidity and moisture and microbiological analysis, and sensory parameters at times 0, 30, 60 and 90 days. In the development of cereal bars, the formulations examined had ash contents of 4.46% to 8.04% (Formulations 9 and 4, respectively), fat 2.8% to 4.61% (Formulations 3 and 5, respectively), and protein 14.2% to 19.19% (Formulations 1 and 10, respectively). The Maoria bars showed sensory acceptance corresponding to "like slightly to like a lot," and had satisfactory results for microbiological analyzes. The formulation 5, added with 2% and 3% seaweed quinoa, achieved the best results concerning the nutritional and sensory quality, thus has been selected for the study of storage stability. The moisture and acidity remained stable after 90 days of storage, similar results were observed for the microbiological quality. According to sesorial analysis, the number 5 cereal bar is framed in sensory acceptance zone in category "like moderately" to "enjoyed". Therefore, it was concluded that the developed cereal bars can become an option for many types of diet or for those seeking a healthier lifestyle, it presented high protein and low fat, as well as showing good sensory acceptance.
A alga Saccharina japonica, conhecida popularmente como “Kombu” é um alimento rico em proteína, fibra e micronutrientes. Esta alga apresenta propriedade antioxidante, antiviral, antitumoral, anti-inflamatória e hipoglicêmica. A quinoa (Chenopodium quinoa Willd) é considerada um pseudocereal que tem como principal característica a qualidade de sua proteína, sendo reconhecida pela Organização Mundial de Saúde (OMS) como um alimento ideal, por sua composição nutricional ser superior à maioria dos cereais. A adição desses dois ingredientes na formulação de barra de cereais salgada poderá agregar um maior valor nutricional a esse produto, que vem apresentando um crescente consumo nos últimos anos. O trabalho teve como objetivo elaborar barras de cereais salgadas adicionadas da alga Saccharina japônica em diferentes concentrações (2, 4, 6, 8, 10%) e de quinoa (1, 2, 3, 4, e 5%), por meio do uso do Delineamento Composto Central Rotacional (DCCR). Uma das formulações das barras de cereal foi selecionada para o estudo de estabilidade ao armazenamento, quanto às análises de acidez e umidade e aos parâmetros microbiológicos e sensoriais, nos tempos 0, 30, 60 e 90 dias. No desenvolvimento das barras de cereal, as formulações analisadas apresentaram teores de cinzas de 4,46% a 8,04% (Formulações 9 e 4, respectivamente), gordura de 2,8% a 4,61% (Formulações 5 e 3, respectivamente), e proteína de 14,2% a 19,19% (Formulações 1 e 10, respectivamente). A maoria das barras apresentou aceitação sensorial correspondente a “gostei ligeiramente a gostei muito”, bem como tiveram resultados satisfatórios para as análises microbiológicas. A formulação 5, adicionada com 2% de alga e 3% de quinoa, obteve os melhores resultados referentes à qualidade nutricional e sensorial, desta maneira foi selecionada para o estudo de estabilidade ao armazenamento. Os teores de umidade e de acidez mantiveram-se estáveis após 90 dias de estocagem, resultado semelhante foi observado para a qualidade microbiológica. De acordo com as análises sesorial, a barra de cereal de número 5 se enquadrou na zona de aceitação sensorial na categoria “gostei moderadamente” a “gostei muito”. Portanto, concluiu-se que as barras de cereais desenvolvidas podem se tornar uma opção para diversos tipos de dieta ou para quem procura uma vida saudável, pois apresentou elevado teor de proteínas e baixo teor de gordura, além de apresentar boa aceitação sensorial.
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Books on the topic "Central composite designs"

1

Hyer, M. W. Innovative design of composite structures: The use of curvilinear fiber format to improve buckling resistance of composite plates with central circular holes. Blacksburg, VA: College of Engineering, Virginia Polytechnic Institute and State University, 1990.

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2

Hyer, M. W. Innovative design of composite structures: The use of curvilinear fiber format to improve buckling resistance of composite plates with central circular holes. Blacksburg, VA: College of Engineering, Virginia Polytechnic Institute and State University, 1990.

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3

Nudo, Raffaele, ed. Lezioni dai terremoti: fonti di vulnerabilità, nuove strategie progettuali, sviluppi normativi. Florence: Firenze University Press, 2012. http://dx.doi.org/10.36253/978-88-6655-072-3.

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This book is a collection of the academic contributions presented at the conference entitled "Lessons from earthquakes: sources of vulnerability, new design strategies and regulatory developments" which was held at Chianciano Terme on 8 October 2010. The issues addressed are central to Seismic Engineering and comprise a wide range of arguments on both consolidated subjects and innovative aspects in the sector. Among these, appropriate attention is devoted to: analysis of the structural instability revealed on the occasion of seismic events and the lessons that can be drawn from the same; the procedures of assessment of the existing buildings, starting from the phase of monitoring and diagnostics through to the definition of the most opportune intervention techniques; the use of composite materials and alternative methods of seismic protection; non-linear field modelling relating to regular and non-regular structures; and finally, the development of the methods of calculation that have characterised the evolution of the regulatory codes.
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4

Kellman, Noah. The Game Music Handbook. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190938680.001.0001.

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Writing music for games is an art that requires conceptual forethought, specialized technical skill, and a deep understanding of how players interact with games and game audio. The Game Music Handbook embarks on a journey through numerous soundscapes throughout video game history, exploring a series of concepts and techniques that are key to being a successful game music composer. This book organizes key game music scoring concepts into an applicable methodology, describing them with memorable distinctions that leave readers with a clear picture of how to apply them to creating music and sound. Any music composer or musician who wishes to begin a career in game composition can pick up this text and quickly gain a solid understanding of the core techniques for composing video game music, as well as the conceptual differences that separate it from any other compositional field. Some of these topics include designing emotional arcs for nonlinear timelines, the relationship between music and sound design, discussion of the player’s interaction with audio, and more. There is also much to be gained by advanced readers or game audio professionals, who will find detailed discussion of game state and its effect on player interaction, a composer-centric lesson on programming, how to work with version control, information on visual programming languages, emergent audio, music for virtual reality (VR), procedural audio, and other indispensable knowledge about advanced reactive music concepts. The text often explores the effect that music has on a player’s interaction with a game. It discusses the practical application of this interaction through the examination of various techniques employed in games throughout video game history to enhance immersion, emphasize emotion, and create compelling interactive experiences.
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Book chapters on the topic "Central composite designs"

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Beg, Sarwar, and Ziyaur Rahman. "Central Composite Designs and Their Applications in Pharmaceutical Product Development." In Design of Experiments for Pharmaceutical Product Development, 63–76. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-4717-5_6.

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Park, Sung Hyun, Hyuk Joo Kim, and Jae-Il Cho. "Optimal Central Composite Designs for Fitting Second Order Response Surface Linear Regression Models." In Recent Advances in Linear Models and Related Areas, 323–39. Heidelberg: Physica-Verlag HD, 2008. http://dx.doi.org/10.1007/978-3-7908-2064-5_17.

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Qiu, Si, Minyu Xie, Hong Qin, and Jianhui Ning. "Study of Central Composite Design and Orthogonal Array Composite Design." In Contemporary Experimental Design, Multivariate Analysis and Data Mining, 163–75. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-46161-4_10.

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Kwon, Chi-Myung. "Application of Central Composite Design to Simulation Experiment." In Lecture Notes in Computer Science, 40–49. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/978-3-540-30585-9_5.

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Rashid, Mir Akmam Noor, Zakaria Mohd Zain, Momin Mullah, and Wazed Ibne Noor. "Analysis and Modeling of Delamination Factor in Milling of JFRP Composite Using Central Composite Design." In Lecture Notes in Mechanical Engineering, 903–16. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-15-9505-9_79.

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Iranmanesh, Soudeh, Alireza Esmaeilzadeh, and Abbas Razavykia. "Optimization of Electrical Discharge Machining Parameters of Co-Cr-Mo Using Central Composite Design." In Sustainable Design and Manufacturing 2017, 48–57. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-57078-5_5.

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Ahn, Haeil. "Central Composite Design for the Experiments with Replicate Runs at Factorial and Axial Points." In Lecture Notes in Electrical Engineering, 969–79. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-47200-2_101.

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Naga Satya Kirti, Chinta, and M. V. Jagannadha Raju. "Optimization of Process Parameters in WEDM on Inconel 600 Using Central Composite Design and Grey Relational Analysis." In Lecture Notes on Multidisciplinary Industrial Engineering, 397–407. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7643-6_32.

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Aht-Ong, Duangdao, Chiravoot Pechyen, and Duangduen Atong. "Evaluation of the Influence of Additives on the Mechanical Properties and Photo-Stability of Glass Fiber Reinforced Epoxy Pipes Using Central Composite Design." In Advanced Materials Research, 349–52. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-463-4.349.

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"Central Composite Designs." In Effective Experimentation, 121–31. Chichester, UK: John Wiley & Sons, Ltd, 2010. http://dx.doi.org/10.1002/9780470666654.ch12.

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Conference papers on the topic "Central composite designs"

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Tew, Jeffrey D. "Using central composite designs in simulation experiments." In the 24th conference. New York, New York, USA: ACM Press, 1992. http://dx.doi.org/10.1145/167293.167634.

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Zhang, Zhihong, and Bai Xiaofeng. "Comparison about the Three Central Composite Designs with Simulation." In 2009 International Conference on Advanced Computer Control. IEEE, 2009. http://dx.doi.org/10.1109/icacc.2009.48.

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Branagan, Michael, Neal Morgan, Brian Weaver, and Houston Wood. "Response Surface Mapping and Multi-Objective Optimization of Tilting Pad Bearing Designs." In ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/gt2017-64949.

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Fluid film bearings for turbomachinery are designed to support the loads applied by the rotor system, often at high speeds when power loss in the bearing becomes significant and bearing temperatures can reach levels that can be detrimental to the long-term reliability of the support system. These requirements of supportive bearings require an intimate understanding of how bearing design variables affect their overall performance. Ideal bearings minimize power loss to increase machine efficiency and maintain low operating temperatures to ensure long-term reliability while meeting other design criteria such as minimum film thickness to provide proper support and avoiding high fluid pressures that can be harmful to the bearing structure. However, real world designs are often forced to sacrifice some of these design goals in order to preserve others. Therefore, further understanding of the relative opportunity costs associated with optimizing the bearing design with differently weighted performance metrics and their relationships to bearing design variables is invaluable to design engineers. This study explores the impact of eight bearing design variables on the performance of two tilting pad journal bearings supporting an eight-stage centrifugal compressor using design of experiments techniques applied to an established thermoelastohydrodynamic (TEHD) bearing model of tilting pad bearing performance. The bearing design variables analyzed include the radial clearance, pad arc spacing, pad axial length, pivot offset, preload, working fluid viscosity and viscosity index, and the number of pads. Each of the design variables — excluding the number of pads which was realistically constrained — were first varied over five levels each in a central composite design. These central composite designs were repeated for each of three values for number of pads. The responses obtained from the TEHD numerical simulations for each bearing design point were power loss, maximum pad temperature, minimum film thickness, and maximum fluid film pressure. The results from the central composite studies were fit with a multivariate least-squares regression model and a secondary series of experimental design studies were simulated around potential optimum design points to obtain a learning set to initialize direct optimization methods. Two direct multi-objective optimization methods, a sequential quadratic programming method and a multi-island genetic algorithm, were performed using Isight, a commercial software. A range of weighting parameters were selected for the optimization functions to find bearing designs that minimized power loss and pad temperature while maintaining pressure and film thickness criteria within acceptable design ranges for fluid film bearings. The resulting optimum design points allowed for a comparison between the design optimization approaches. The various strengths and weaknesses of the different methods are discussed. This study demonstrates how designers can use these approaches to view the relationships between design variables and important performance metrics to design better bearings for a wide range of applications.
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Chen, Han-Ting, Jenn-Tsong Horng, and Ying-Huei Hung. "Optimal Thermal Design for PPF Heat Sinks." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-41750.

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An effective method for predicting and optimizing the thermal performance of Parallel-Plain Fin (PPF) heat sinks that satisfy given design constraints has been successfully developed in the study. The thermal and hydrodynamic performance analyses for PPF heat sinks have been conducted. The Response Surface Methodology (RSM) is applied to establish analytical models of the thermal resistance and pressure drop in terms of the design variables with a Central Composite Design (CCD) experimental design. A constrained optimization technique, Sequential Quadratic Programming (SQP), is employed to efficiently seek the optimal designs; and the comparisons between these predicted optimal designs and those evaluated by the theoretical calculations are made with a satisfactory agreement.
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Wang, G. Gary. "Improvement on the Adaptive Response Surface Method for High-Dimensional Computation-Intensive Design Problems." In ASME 2001 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/detc2001/dac-21141.

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Abstract This paper addresses the difficulty of the previously developed Adaptive Response Surface Method (ARSM) for high-dimensional design problems. The ARSM was developed to search for the global design optimum for computation-intensive design problems. This method utilized the Central Composite Designs (CCD), which resulted in an exponentially increasing number of required design experiments. In addition, the ARSM generates a complete new set of CCDs in a gradually reduced design space. These two factors greatly undermine the efficiency of the ARSM. In this work, the Latin Hypercube Designs (LHD) were utilized to generate saturated design experiments. Because of the use of Latin Hypercube Designs, the historical design experiments can be inherited in later iterations. The improved ARSM has been tested using a group of standard testing problems and then applied to an engineering design. In both testing and design application, significant efficiency improvement of the ARSM was observed. The ARSM at the current stage demonstrated strong potential to be an efficient global optimization tool for computation-intensive design problems.
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Riglin, Jacob, W. Chris Schleicher, and Alparslan Oztekin. "Diffuser Optimization for a Micro-Hydrokinetic Turbine." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-37304.

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Small, hydrokinetic systems generating between 0.5 and 10 kW of power are potentially capable of portable power generation. A propeller turbine 18 inches in diameter is paired with a flanged diffuser and numerically simulated as a potential portable hydrokinetic system. The diffuser augmented hydrokinetic turbine (DAHkT) is investigated with a response surface optimization method, where geometric parameters of the system are systematically varied to determine their effects on the system power generation and thrust. The simulations are determined using a central composite design of experiments to minimize the number of simulations required to fit a second-order regression to the results. Potential optimum designs are determined from the regression model, further verified with simulations, and characterized for their entire operating range.
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Wang, M. P., H. T. Chen, J. T. Horng, T. Y. Wu, P. L. Chen, and Y. H. Hung. "Thermal Optimal Design for Partially-Confined Compact Heat Sinks." In ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems collocated with the ASME 2005 Heat Transfer Summer Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/ipack2005-73118.

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An effective method for predicting the optimal thermal performance of partially-confined compact heat sinks under multi-constraints of pressure drop and heat sink mass has been successfully developed. The design variables of PPF compact heat sinks include: heat sink fin and base material, thickness of heat sink base, heat flux, channel top bypass and inlet flow velocity. A total of 108 experimental cases for confined forced convection are designed by the Central Composite Design (CCD) method. According to the results in ANOVA, a sensitivity analysis for the design factors is performed. From the analysis, the effect of inlet flow velocity, which has the contribution percentage of 86.24%, dominates the thermal performance. The accuracies of the quadratic RSM models for both thermal resistance and pressure drop have been verified by comparing the predicted response values to the actual experimental data. The maximum deviations of thermal resistance and pressure drop are 9.41% and 7.20% respectively. The Response Surface Methodology is applied to establish analytical models of the thermal resistance and pressure drop constraints in terms of the key design factors with a CCD experimental design. By employing the Sequential Quadratic Programming technique, a series of constrained optimal designs can be efficiently performed. The numerical optimization results for four cases under different constraints are obtained, and the comparisons between these predicted optimal designs and those measured by the experimental data are made with a satisfactory agreement.
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Sigel, Deborah, Brian P. Trease, Mark W. Thomson, David R. Webb, Paul Willis, and P. Doug Lisman. "Application of Origami in the Starshade Spacecraft Blanket Design." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-34315.

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A Starshade is a large deployable structure and sole payload of an external occulter. At 34m in diameter or more, starshades are designed to block most of the light from a nearby star so that a small orbiting space telescope can image and characterize the Earth-like exoplanets in orbit around it. The starshade resembles a sunflower with a circular central disk supporting petals that are arrayed around its periphery. The petal edges are precisely shaped to match an optical profile that prevents diffraction. The area circumscribed by the edges must be completely opaque, black, and non-reflective. The petals and ring structure are covered by specially designed deployable blankets that must remain completely opaque even if they become perforated by micrometeorites. The blankets must also not cause any significant on-orbit thermoelastic loads on the lightweight supporting ring and petal structures despite very large differential thermal strains that are developed between these Kapton blankets and the thermally stable composite ring and petal structures. There are two types of blankets: one for the deployable petals and one for the central support disc that is formed by a lightweight deployable ring truss structure. The starshade blankets cover such a large area that they must be unusually lightweight compared to conventional multi-layer insulated (MLI) spacecraft blankets. The blankets must also stow around the central hub of the spacecraft with the deployable ring and petal structures in a highly repeatable fashion. This makes them ideal candidates for origami folding schemes. Based on prior studies of large deployable rigid arrays, we began with variants on the origami flasher to fold the central ring blanket, which is a minimum of 20m in diameter. We looked at the simplest methods for integrating this large blanket with a mechanical ring truss while providing ample optical baffling and little to no thermally induced loads on the structure. Petal blankets were also developed using deployable softgoods with pseudo-mechanical and shingled designs with optically blocking folds for deployment. The design was developed iteratively utilizing a variety of prototypes to explore and demonstrate the interaction between the softgoods and rigid elements.
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Sapanaro, Michael, Suhash Ghosh, and Chittaranjan Sahay. "Motorcycle Swing Arm Development and Refinement Using Response Optimization." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51670.

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The purpose of this project is to develop a motorcycle rear swing arm using finite element analysis and response optimization. This paper aims to discuss the specific features, benefits, and precautions when using design optimization to develop a specific project. Design Optimization has been an evolving process for many years. The latest versions of finite element software allow users to develop, analyze, and optimize structural designs within one program quickly and efficiently. A single shock absorber mounted close to the chassis and centrally located was the design selected to be analyzed. The design was selected for use in a variety of motorcycle types. This project consisted of a unique set of design attributes that were ideal to exemplify design optimization techniques. Static structural models were created to refine the design before using response optimization. These models finalized the material selection and initial sizes. A central composite design type was generated with selected boundary conditions for four parametric dimensions of the model. The ideal design of this component would include the resulting stress below a safe allowable value, minimal deflection, and the least amount of weight. It is evident that these three parameters will oppose one another as geometry is changed. Conceptually, an ideal candidate can be created that is a balance of the three parameters. Using the parameters of the selected candidate, a new model was generated for analysis. The final model was further refined by removing unnecessary material that was identified in the structural models. The first step in a thorough optimization is generating an appropriate amount of design parameter values that are an acceptable representation of all the possible outcomes, or design of experiments (DOE). The DOE tool used to generate the parameters in this project was central composite design (CCD), since it is the most appropriate for second order response models [1]. The second order relationship was confirmed using a trade-off plot. The two level, four input parameter DOE produces twenty five potential candidates that were refined using response surface. The response surface method used in this design process [2,3] to make judgement calls on the final design is examined during this development, and proves useful. Initial static structural models are created and used to set up the model for optimization. Material selection was also accomplished in this phase of development. This process aides in the overall design process by identifying areas of concern as well as the range of parameters that will be analyzed. Multiple acceptable candidates were selected through the use of the optimization tools and a final candidate was selected based on the output of the design attributes and the values of the corresponding parametric geometry. The final selection was also made with the consideration for cost, ease of fabrication, and standardization.
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Huber, Michael, and Dharma Wijewickreme. "Response of Buried District Heating Pipelines Under Relative Axial Movements." In 2014 10th International Pipeline Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/ipc2014-33530.

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District heating (DH) systems are commonly used in urban areas to distribute thermal energy from central heat sources. Buried pipes, with a composite cross-sectional construction, are used transport a heated medium, usually water. These pipes expand and contract radially and axially due to changing water temperatures, invoking soil-pipe interaction situations during operation, and potentially leading to significant pipeline material strains. A series of full-scale tests were undertaken to specifically investigate the influence of thermal expansion on axial pullout resistance using DH pipes buried in sand in a full-scale soil-pipe interaction test chamber. During testing, the pipe is filled with water that is subjected to temperature changes to simulate field conditions. Axial pipe pull-out tests were conducted after applying a given “heating history” with axial pullout force and displacements recorded. The work leads to better understanding of soil-pipe interaction mechanisms generating currently scarce data needed for robust and cost-effective designs of DH pipe systems.
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Reports on the topic "Central composite designs"

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Thompson, Marshall, and Ramez Hajj. Flexible Pavement Recycling Techniques: A Summary of Activities. Illinois Center for Transportation, July 2021. http://dx.doi.org/10.36501/0197-9191/21-022.

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Cold in-place recycling (CIR) involves the recycling of the asphalt portions (including hot-mix asphalt and chip, slurry, and cape seals, as well as others) of a flexible or composite pavement with asphalt emulsion or foamed asphalt as the binding agent. Full-depth reclamation (FDR) includes the recycling of the entire depth of the pavement and, in some cases, a portion of the subgrade with asphalt, cement, or lime products as binding agents. Both processes are extensively utilized in Illinois. This project reviewed CIR and FDR projects identified by the Illinois Department of Transportation (IDOT) from the Transportation Bulletin and provided comments on pavement designs and special provisions. The researchers evaluated the performance of existing CIR/FDR projects through pavement condition surveys and analysis of falling weight deflectometer data collected by IDOT. They also reviewed CIR/FDR literature and updated/modified (as appropriate) previously provided inputs concerning mix design, testing procedures, thickness design, construction, and performance as well as cold central plant recycling (CCPR) literature related to design and construction. The team monitored the performance of test sections at the National Center for Asphalt Technology and Virginia Department of Transportation. The researchers assisted IDOT in the development of a CCPR special provision as well as responded to IDOT inquiries and questions concerning issues related to CIR, FDR, and CCPR. They attended meetings of IDOT’s FDR with the Cement Working Group and provided input in the development of a special provision for FDR with cement. The project’s activities confirmed that CIR, FDR, and CCPR techniques are successfully utilized in Illinois. Recommendations for improving the above-discussed techniques are provided.
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