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Sodium alginate and magnetic iron oxide nanoparticles were combined to produce magnetic nanocomposite beads that were used for the removal of Cu(II) from aqueous solutions at a temperature of 25°C and a stirring rate of 150 rpm. The different parameters affecting the adsorption capacity of the synthesized material such as contact time (30-270 min), pH (3-7), adsorbent dosage (5-10 g per 50 mL of wet beads), and initial Cu(II) concentration (50-450 mg/L) were investigated. Of all of the variables, the solution pH has the most significant effect on the adsorption capacity, particularly in the range of 4- 6. Response surface methodology was used for modeling and optimizing the uptake process. While the experimental data were well described by the pseudo-second-order model, the adsorption isotherms were better fitted by the Langmuir equation. The results revealed that the maximum removal percentage was 92.6% from the initial Cu(II) concentration (150 mg/L) at pH 6, adsorbent dose (8.0 g/50 mL), and contact time (210 min). Therefore, the synthesized magnetic nanocomposite product could act as a highly effective nanoadsorbent in Cu(II) removal from the aqueous solutions. Key words: water treatment, magnetic nanocomposite, Cu(II) removal. Nous avons combine l'alginate de sodium avec des nanoparticules d'oxyde de fer magnetique pour produire des billes de nanocomposite magnetique qui ont servi au piegeage du Cu(II) en solution aqueuse a une temperature de 25°C et une vitesse d'agitation de 150 tours/min. Les differents parametres intervenant dans la capacite d'adsorption du materiau synthetise suivants ont ete examines: le temps de contact (compris entre 30 et 270 min), le pH (compris entre 3 et 7), la concentration de l'adsorbant (comprise entre 5 et 10 g par 50 mL de billes imbibees) et la concentration initiale du Cu(II) (comprise entre 50 et 450 mg/L). Parmi toutes les variables, c'est le pH de la solution qui produit l'effet le plus important sur la capacite d'adsorption, surtout a des valeurs comprises entre 4 et 6. Nous avons utilise la methode de surface de reponses pour modeliser et optimiser le processus de piegeage. Alors que les donnees experimentales correspondaient bien au modele de pseudo deuxieme ordre, les isothermes d'adsorption etaient mieux decrites par l'equation de Langmuir. Les resultats ont revele que le pourcentage maximal de piegeage etait de 92,6 % a une concentration initiale de Cu(II) de 150 mg/L, un pH de 6, une concentration d'adsorbant de 8,0 g par 50 mL et un temps de contact de 210 min. Par consequent, le produit nanocomposite magnetique synthetise pourrait etre hautement efficace comme nanoadsorbant dans le piegeage du Cu(II) en solution aqueuse. [Traduit par la Redaction] Mots-cles: traitement par l'eau, nanocomposite magnetique, piegeage du Cu(II)., Introduction It is well known that water is a fundamental challenge to people, which is known as blue gold. It declines quantitatively and qualitatively due to different effluents and chemical [...]

This paper deals with optimum design criteria for maximum torque density and minimum torque ripple of synchronous reluctance motor (SynRM) according to the rated wattage using response surface methodology (RSM). The RSM has been achieved to use the experimental design method in combination with finite element method and well adapted to make analytical model for a complex problem considering a lot of interaction of design variables. The proposed procedure allows to define the rotor optimum shape for maximum torque density and minimum torque ripple starting from an existing motor or a preliminary design. Index Terms--Finite element method (FEM), response surface methodology (RSM), synchronous reluctance motor (SynRM), torque ripple.

The support vector machine (SVM) is proposed as a response surface model to accelerate the solution speed of metaheuristic algorithms in solving inverse problems. The detail formulations of the SVM regression model using [epsilon]-insensitive loss function are derived. Primary numerical results are reported to demonstrate the feasibility, performance, and robustness of the proposed SVM based response surface model for solving both mathematical functions and engineering design problems. Index Terms--Inverse problem, metaheuristic algorithm, response surface model, support vector machine (SVM).

Cassava starch was chemically modified to produce an amphoteric starch. The amphoteric starch was prepared in a simultaneous process which was evaluated in relation to four factors: temperature (45-55 [degrees]C), 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTAC, 4-12%) and sodium tripolyphosphate (STP, 2-8%) concentrations, and reaction time (2-6 h). The extent of amphoteric starch produced was determined by the degree of substitution (DS) of the nitrogen content and percentage of phosphorus content. In addition, a quantitative response of yield and whiteness as well as pasting characteristics were tested. Response surface analysis showed that the DS (0.01-0.05) increased with increasing temperature, CHPTAC and reaction time. The phosphorus content (0.09-0.34%) followed a parabolic shape with all of the factors. Consequently, the response surface methodology appears to be a powerful technique to determine the optimal conditions for the production of amphoteric starches. Keywords: Amphoteric starch, Box-Behnken design, Response surface methodology, INTRODUCTION Cassava starch is an important food ingredient in tropical countries such as Brazil, Nigeria, Indonesia and Thailand. Cassava starch has often been modified, and Thailand is also a country [...]

A response surface methodology approach to wind-tunnel testing of high-performance aircraft is being investigated at the Langley Full-Scale Tunnel. An exploratory study was completed using a newly developed response surface methodology design in an effort to better characterize an aircraft's aerodynamic behavior while simultaneously reducing test time. This new design called a 'nested face-centered design' was developed when classic designs were found to have inadequate prediction qualities over a cuboidal design space with factors at five levels. A 19% scale modified X-31 aircraft model was chosen for evaluation of the new response surface methodology design based on its nonlinear aerodynamic behavior at high angle of attack that is representative of modern fighter aircraft and due to a substantial preexisting data base. A five-level nested fractional factorial design, augmented with center points and axial points, produced regression models including pure cubic terms for the characteristic aerodynamic forces and moments over a cuboidal design space as a function of model position and control surface deflections. Model adequacy and uncertainty levels were described using robust statistical methods inherent to response surface methodology practice. Comparisons to baseline data and sample lateral-directional and longitudinal aerodynamic characteristics are given as validation of the new design.

A report on approach to doing ridge analysis in presence of noise variables for optimizing a response surface using Peterson method of analysis is presented.

Byline: PA+-nar Demirekler (1), Gulum Sumnu (1), Serpil Sahin (1) Keywords: Bread; Baking; Microwave; Halogen lamp; Optimization; Response surface methodology Abstract: The main objective of this study was to optimize the baking conditions of bread in a halogen lamp--microwave combination oven. Independent variables were the baking time (4, 4.5, 5, 5.5, and 6 min), the power of the microwaves (20, 30, 40, 50, and 60%), and the power of the upper and lower halogen lamps (40, 50, 60, 70, and 80%). The quality parameters measured were the weight loss, the color, the specific volume, the porosity, and the texture profile of the breads. For the optimization, the response surface methodology was used. Baking time, upper halogen lamp power, and microwave power were found to be significant in affecting most of the quality parameters. On the other hand, the lower halogen lamp power was found to be an insignificant factor. The optimum baking conditions in the halogen lamp--microwave combination oven were determined as 5 min of baking time at 70% upper halogen lamp power, 50% lower halogen lamp power, and 20% microwave power. Breads baked at the optimum condition had comparable quality with conventionally baked ones. When the halogen lamp--microwave combination oven was used, the conventional baking time of breads was reduced by 60%. Author Affiliation: (1) Food Engineering Department, Middle East Technical University, 06531, Ankara, Turkey Article History: Registration Date: 15/06/2004 Received Date: 07/05/2004 Online Date: 07/08/2004

Byline: Ramakrishna Chetana (1), Balaraman Manohar (2), Sunki Reddy Yella Reddy (1) Keywords: Gulab jamun; Indian traditional sweet; Sugar; Sorbitol; Alternative sweetener; Response surface methodology Abstract: Models capable of predicting the product quality of Gulab jamun using sugar and a sugar substitute have been developed using response surface methodology (RSM) and applied to determine the optimum processing conditions. Box--Behnken design was used considering three independent variables, namely concentration (degB) of syrup, its temperature and time of soaking, each at three different levels. The dependent variable or response measured for each treatment was a sensory score for overall quality, which is taken as a combination of the sensory impact of colour, appearance, texture, mouthfeel, taste and aroma. According to RSM, the optimum score for overall quality attained for Gulab jamun prepared with sugar was 7.7, obtained at processing conditions of 51degB syrup, 54 degC and 4 h soaking, whereas for the Gulab jamun prepared with the sugar substitute, sorbitol, a maximum overall quality score of 8.0 was obtained at processing conditions of 54degB syrup, 65 degC and 3 h soaking. These processing conditions were found to correlate with those of experimental conditions. Author Affiliation: (1) Lipid Science &amp Traditional Foods Department, Central Food Technological Research Institute, 570 013, Mysore, India (2) Food Engineering Department, Central Food Technological Research Institute, 570 013, Mysore, India Article History: Registration Date: 08/06/2004 Received Date: 30/03/2004 Online Date: 04/08/2004

Byline: V. Nanda (1), S. Singh (1), C. S. Raina (1), N. Jindal (1), K. Singh (2), D. C. Saxena (1) Keywords: Paneer; Citric acid; Stabilizer; Response surface methodology; Optimization Abstract: Models capable of predicting the quality and yield of processed paneer have been developed using response surface methodology to determine the optimum processing conditions. Three and four-dimensional response surfaces were drawn and the individual contour plots of the different responses were superimposed, and regions meeting the maximum sensory score (29.50--30.75) and yield (9.50--10.50 g/100 g) were identified at 70.1+-2.0 degC at 4.85+-0.23 pH and 2.908+-0.113 g/kg stabilizer concentration. These predicted values for optimum process conditions were in good agreement with experimental data. Author Affiliation: (1) Department of Food Technology, Sant Longowal Institute of Engineering and Technology, Longowal, India (2) Department of Biochemical Engineering and Food Technology, H.B. Technological Institute, Kanpur, India Article History: Registration Date: 13/02/2004 Received Date: 28/07/2003 Online Date: 12/03/2004

Byline: Emir AyAe Azer (1), Senol Adegbanoglu (2), Paul Ainsworth (3), Cahide Yagmur (1) Keywords: Extrusion cooking; Snack food; Expansion; Nutrition; Response surface methodology Abstract: Response surface methodology was used to analyze the effect of screw speed (220--340 rpm), feed moisture (11.0--15.0%, wet basis) and feed rate (22.0--26.0 kg/h, wet basis) on the physical properties (i.e., bulk density, expansion, porosity) of a nutritionally balanced extruded snack food. Regression equations describing the effect of each variable on the responses were obtained. Responses were most affected by changes in screw speed followed by feed moisture and feed rate (P&lt 0.05). Expansion and porosity increased with screw speed and feed moisture whereas the opposite was observed for bulk density. Radial expansion was found to be a better index to measure the extent of expansion than the axial and overall expansions, indicated by a higher correlation coefficient. Author Affiliation: (1) Food Engineering Department, Agricultural College, Cukurova University, Adana, Turkey (2) Food Engineering Department, Engineering Faculty, Gaziantep University, Gaziantep, Turkey (3) Department of Food and Consumer Technology, Hollings Faculty, The Manchester Metropolitan University, Old Hall Lane, Manchester, M14 6HR, UK Article History: Registration Date: 16/01/2004 Received Date: 28/07/2003 Online Date: 06/02/2004

Byline: S. Singh (1), C. S. Raina (1), A. S. Bawa (2), D. C. Saxena (1) Keywords: Sweet potato chips; Texture; Response surface; Optimisation; Crispness Abstract: Models capable of predicting the product quality of sweet potato chips have been developed using response surface methodology and used to determine the optimum processing conditions. Moisture loss, oil uptake, crispness (measured using a bending-snapping test in the TA.XT2 Texture Analyser), and sensory attributes such as colour, flavour, and texture were used to assess the product quality in the preparation of sweet potato chips. The optimum conditions which were attained for maximum moisture loss (11.65% on wet basis), minimum oil uptake (2.57%), crispness (794.37 g), colour score (7), flavour score (7) and texture score (7) were: frying temperature, 174.7 degC salt concentration, 0.45% citric acid concentration, 0.37% potassium metabisulphite concentration, 0.65% and frying time, 26 s. Author Affiliation: (1) Department of Food Technology, Sant Longowal Institute of Engineering and Technology, Longowal, India (2) Defence Food Research Laboratory, Mysore, India Article History: Received Date: 05/05/2003 Online Date: 22/08/2003

Byline: C. I. Clarke (1,2), T. J. Schober (1,2), E. Angst (1,2), E. K. Arendt (2) Keywords: Sourdough; Wheat bread; Response surface methodology Abstract: Response surface methodology was used to investigate the influence of three factors, sourdough fermentation time, proof time and amount of yeast addition on the quality of sourdough wheat bread. Each predictor variable was tested at five levels. Sourdough fermentation times were 5, 11, 20, 29 and 35 h, yeast addition rates were 0.05, 0.75, 1.77, 2.80 and 3.50% (flour weight basis) and proof times were 16, 40, 75, 110 and 134 min. The performance of two different starter culture types, a mixed strain starter culture called Bocker Reinzucht--Sauerteig Weizen and a single strain starter culture of Lactobacillus brevis, was compared by separately completing the experimental design for each. Independently non-acidified control bread was prepared. A range of loaf quality parameters was determined including pH, total titratable acidity, loaf height, specific volume, crumb mean cell area and crumb hardness. Overall breads with better specific volume values were achieved with the use of sourdough relative to the control. Results indicated that maximum loaf specific volume was achieved when L. brevis sourdough was used particularly when it was used in conjunction with a high rate of yeast. Given a lower rate of yeast addition however, the mixed strain starter culture yielded better bread. Author Affiliation: (1) National Food Biotechnology Centre, National University of Ireland, Cork, Ireland (2) Department of Food and Nutritional Sciences, National University of Ireland, Cork, Ireland Article History: Received Date: 03/02/2003 Online Date: 10/05/2003

A study to optimize probiotic bacterial cultures in fermented milk is presented. Genetic algorithms are used for the study.

Use of mixture response surface methodology, to study the influence of film compostion on potassium sorbate diffusibility, through edible films of whey proteins, is discussed.

Results demonstrate that optimum diffusers show minimal separation of flows and give similar wall shapes as revealed by the polynomials and B-splines parameters. Data indicate that usefulness of response surface optimization is in the smoothing of noisy response functions.

Byline: Kondabagil R. Kiran (1), Balaraman Manohar (2), Nayakanakatte G. Karanth (1), S. Divakar (1) Keywords: Palmitoyl lactic acid; Enzyme/substrate ratios; Lactic acid/palmitic acid concentrations; Iso-esterification regions Abstract: .sub.s), enzyme/substrate (E/S) ratios (X .sub.e) and incubation time (X .sub.t) on the preparation of palmitoyl lactic acid using Mucor miehei lipase (MML) and porcine pancreas lipase (PPL). Experimental ester yields were found to be in good agreement with predictions. In the case of MML, the ester yield was found to increase with X .sub.e and X .sub.t and a maximum yield of 27mM was obtained at X .sub.e=128 activity units(AU)/mM of substrate, X .sub.s=64--74mM and X .sub.t=72h. In the case of PPL, the ester yield was found to increase with increases in X .sub.e and X .sub.s. Optimum conditions for PPL were X .sub.e=45AU/mM, X .sub.s=85--90mM and X .sub.t=72h, at which the maximum ester yield of 15mM was obtained. Author Affiliation: (1) Fermentation Technology and Bioengineering Department, Central Food Technological Research Institute, Mysore -- 570 013, India e-mail:divakar@nicfos.ernet.in, IN (2) Food Engineering Department, Central Food Technological Research Institute, Mysore -- 570 013, India, IN Article note: Received: 14 April 1999 / Revised version: 2 September 1999

Byline: G. Began (1), B. Manohar (1), K. Udaya Sankar (1), A.G. Appu Rao (2) Keywords: Key wordsaResponse surface methodology; Solubility; Soy lecithin; Super critical carbon dioxide; Total lipid Abstract: aThe solubility of soy lecithin lipids in supercritical CO.sub.2 was measured at pressures of 120, 200 and 280bar and at temperatures of 40, 50 and 60aadegC. The effects of temperature and pressure on the solubility of total lipids were studied by response surface methodology. The response surface equation to predict the solubility of total lipids in the above range of pressure and temperature is: Y=--3.237+0.0431* P--7.3x10.sup.--5 P .sup.2--0.00011 P*T where Y is the total lipid solubility in g/kg CO.sub.2, P is the pressure in bar and T is the temperature in aadegC. The total lipids solubility increased with pressure at constant temperature, but decreased with increasing temperature. The total lipids consisted of a very small phospholipid content compared to neutral lipids and glycolipids at all the pressures and temperatures studied. Optimum search indicated a maximum solubility of total lipids of 1.829g/kg CO.sub.2 at 263 bar and 40aadegC. Author Affiliation: (1) Department of Food Engineering, Central Food Technological Research Institute, Mysore - 570 013, India e-mail: udaya@nicfos.ernet.in, IN (2) Department of Protein Chemistry and Technology, Central Food Technological Research Institute, Mysore - 570 013, India, IN Article note: Received: 1 April 1999

Byline: M. D. Alvarez (1), W. Canet (1) Keywords: Key wordsaPotato; Rheological parameters; Blanching; Freezing; Response surface methodology Abstract: aResponse surface methodology was used to compare the effect of temperature and time of the first step of blanching on compression, shear, tension and stress-relaxation parameters of frozen-thawed potato tissues. A central, composite rotatable design was used to study the effects of variation in levels of temperature (52.93--67.07aadegC) and time (15.86--44.14min) on rheological parameters. Blanching temperature was the most important factor affecting the mechanical properties tested. The models fitted for the apparent modulus of elasticity in compression, maximum tension force, and relaxed force in the first cycle (F .sub.r1) all had R .sup.2&gt 0.85 (Pa$?0.01) and were used for doing predictions. Optimum conditions were with in the ranges of temperature (60--65aadegC) and time (25--35min) used for each factor. In the experimental verification of the models at 65aadegC during 30min, the lowest percentage residual between experimental and predicted values was obtained for F .sub.r1 (0.644), which was therefore the most appropiate parameter for detecting the firming effect that the pectinesterase activity produced on frozen potato tissues as a consequence of stepwise blanching under these conditions. Author Affiliation: (1) Department of Plant Food Science and Technology, Instituto del Frio-CSIC, Ciudad Universitaria s/n, E-28040 Madrid, Spain e-mail: ifrat44@if.csic.es, ES Article note: Received: 3 February 1999 / Revised version: 12 April 1999

The use of a response surface in the design of an electromagnetic system is described. The surface is generated using a minimum number of points based on the Design of Experiments. The final surface is integrated in SPICE to provide dynamic performance modeling. Index Terms - Response surfaces, Sensitivity, Coupled problems, Finite element methods.

Byline: N. K. Rastogi (1), K. R. Rashmi (1) Keywords: Mango; Enzymatic liquefaction; Optimisation; Response surface methodology; Central composite rotatable design Abstract: Enzymatic liquefaction of the Neelam variety of mango pulp has been optimised by response surface methodology. The effect of enzyme concentration and incubation time and their complex interaction on juice yield, clarity of the juice, alcohol-insoluble solids and viscosity of the mango pulp have been studied using a central composite rotatable design of experiments. The results showed that at the optimum condition (enzyme concentration and incubation time of 0.14% and 46.67min, respectively) the yield was aY=64%, clarity aY=71%, alcohol-insoluble solids a$?2.0% and viscosity a$?1850cP. Author Affiliation: (1) Department of Food Engineering, Central Food Technological Research Institute, Mysore 570 013, India, IN Article note: Received: 28 May 1998

Neural networks have been found to be applicable in generating response surface methodology. The two-stage approach to generating the best parameters for an unknown model first involves neural networks being trained to identify an unknown function and then to identify the derivatives of this function generated by the first neural network. The neural networks are then iteratively used to compute parameters that optimize the function.

In this paper, we present a design and optimization procedure which utilizes a case-based approach in design and a response surface methodology, implementing a fractional factorial approach, to determine the empirical models relating the performance of the device and the design parameters. With these models constructed, a genetic algorithm can be used to solve the resulting constrained nonlinear optimization problem quickly to get the optimal device. The main contribution of the paper lies in the effective combination of these three methods.

Byline: C. GoA'mez-GuilleA'n (1), RogeA'rio Mendes (2), P. Montero (1) Keywords: Key wordsaSardine; Mince; Texture profile analysis; Washing water; Pyrophosphate Abstract: aIn order to determine the effect of washing water parameters [pH, hardness and tetrasodium pyrophosphate (TSPP) content] on the water-holding capacity (WHC) and gelation properties of sardine (Sardina pilchardus) mince, two experiments designed by response surface methodology were carried out. The WHC of the mince was maximum when washed in the pH range of 6.5--7.0, with TSPP&gt 1.7agal.sup.-1, and CaCO.sub.3 between 30 and 60amgal.sup.-1. With the exception of breaking deformation and the folding test, where the highest values were obtained at 60amgal.sup.-1 CaCO.sub.3, the variation of water hardness did not induce any significant changes in the other rheological parameters. The use of relatively high concentrations of TSPP in the leaching water contributed to the achievement of high values of breaking deformation, though beyond 2.5agal.sup.-1 a detrimental effect on breaking force was observed, and consequently also on gel strength. Author Affiliation: (1) Instituto del Frio (IF), Ciudad Universitaria, E-28040 Madrid, Spain, ES (2) Instituto de Investigacao das Pescas e do Mar (IPIMAR), Av. Brasilia, P-1400 Lisbon, Portugal, PT Article note: Received: 4 March 1996

The use of factorial methods to clarify significant variables and a response-surface analysis to ferret out more details was found to be effective in providing information useful to process optimization as well as efficient in making use of experimental results. This experimental approach was applied in studying the effect of process variables on alkalization and elimination of contaminating toxic metals from a simulated acid leachate by continuous mixed cultures of sulphate-reducing bacteria.

The characteristics of S[F.sub.6]/He plasmas used to etch TiW have been studied with statistically designed experiments using a Tegal 804 single wafer system. Two processes were developed using both positive and negative photoresist as the mask material for etching TiW. The goal was to consolidate both processes into one. A two-phase experimental approach was taken to generate the processes. In phase I a fractional factorial screening experiment was used to identify key factors, and in phase 2 a mixture experiment was used for process optimization. The fractional factorial experiment was initially used to study the effects of reactor pressure, RF power, S[F.sub.6]/He gas ratio, overetch time, and hard bake. The results of this initial experiment were used to identify the appropriate levels for the main process parameters. Then, at these parameter levels, a mixture experiment was conducted using the partial pressures of S[F.sub.6], He, and the nitrogen ballast as the design variables. Since the total pressure in the system is fixed, these three variables are the components of a mixture, and thus form a constrained design space for the experiment. Quadratic and special cubic response surface models were generated for the following responses: TiW etch rate, photoresist etch rate, selectivity between the TiW and photoresist, uniformity of all etch rates and selectivities, and critical dimension control for the photoresist and TiW. Contour plots for all responses as a function of the partial pressure of S[F.sub.6], He, and nitrogen ballast were generated. The contours from these empirical models were analyzed jointly to optimize the processes.

Washing sunflower heads for 25 minutes at 74.8 degree celsius at a 25:1 water/solid ratio (w/v) removes 56.47% of the pigments and only 2.90% of the pectin. The optimum conditions for washing the sunflower heads to remove the maximum amount of pigments and minimum amount of pectin have been obtained using response surface methodology. Both pectin loss (PL) and pigment removal (PR) increase with an increase in washing time and temperature, and water/solid ration. The washing temperature has the greatest effect on PL and PR, and water/solid ratio has the least effect.

Response surface methodology shows that 57% of the proteins in defatted low-mucilage flaxseed meal are extracted using an aqueous solution with a pH of 9.0, 2.89% w/v of sodium hexametaphosphate (SHMP) and a meal-to-solvent ratio (X(sub 2)) of 1:33 (w/v). A solution with a pH of 8.9, 2.75% v/w of SHMP and a X(sub 2) of 1:33 (w/v) extracts 77% of the total nitrogen. Multiple regression analysis shows that pH has the greatest effect on protein and nitrogen extraction while X(sub 2) has the least effect.

Response Surface Methodology correctly predicts proteolytic activities in fish muscles under the influence of pH, hydrostatic pressure, and inhibitors. For increased pressure and inhibitor concentrations, the enzyme activity diminishes. An increase in pH produces a quadratic response. The viscosity of the tissue homogenate decreases with a decrease in pH and an increase in pressure. The presence of a crude inhibitor in the homogenate restricts protease activity during the storage of fish.

A method is presented to efficiently approximate the failure probability of structures subjected to time-variant loads, where the system of loads and structure may have uncertain parameters. The method uses response surface methodology in conjunction with the fast integration technique suggested by Wen and Chen, to provide a limit-state formulation that is computationally simple to solve based on a small number of response time histories. The system reliability may then be quickly computed by first-order reliability method (FORM)/second-order reliability method (SORM) or Monte Carlo simulation. Sensitivity analysis is performed to determine the effect on the failure probability of changes to the system parameters, which can be important when determining whether uncertainty in a given system parameter is significant. An empirical measure of the accuracy of the response surface approximation is presented.

The presence of high fructose corn syrup and hydrocolloids such as xanthan or hydroxypropyl methyl cellulose in a reduced calorie fruit syrup model affects the sensory and viscosity properties. Model syrups with a high gum content have higher viscosity and slipperiness, but lower pourability and adsorption into pancakes. An increase in soluble solids decreases the viscosity and slipperiness. The presence of gums and solids has no effect on the sweetness of the model syrups. Response surface methodology is used for the statistical analysis of the different syrup products.

Response surface methodology (RSM) is used for the optimization of the enzymatic synthesis of structured lipids. The synthesis of structured lipids involves the enzymatic transesterification of ethyl caprylate, soybean oil, and sunflower oil in hexane. RSM optimizes the molar ratio of ethyl caprylate to total triglycerides, long-chain triglyceride concentration, the percentage of soybean oil, and incubation time. Using this method, the desirable linoleic acid and caprylic acid content in structured lipids can be obtained.

It may be possible to restructure sweetpotato puree with cellulose derivatives. The optimum concentrations of alginate, tetrasodium pyrophosphate and calcium sulfate are used for texturizing sweetpotato puree. The response surface statistical pattern supplemented with instrumental texture profile parameters are utilized for obtaining the best alginate-textured products. The reconstructed sweetpotatoes possess the required textural and flavor. Maybe this technique could be used to make other kinds of processed products from sweet potatoes.

This paper describes a methodology that can be used for the optimization of semiconductor processes. This is achieved by integrating the design of experiments and Response Surface Methodology (RSM) with process and device simulation tools. Software for automating multiple simulations has been implemented and interfaced to RS/1 to assist in the manual design and analysis of experiments and the subsequent optimization procedures. The procedure is illustrated through the optimization of part of an MOS process with multi-parameter optimization being performed by the introduction of composite responses and sensitivity analysis. These simulated results are also compared with experimental measurements.

Under general conditions reliability analyses of elaborate structural models can be replaced by much simpler equivalent reliability analyses of corresponding idealized structural models such as those based on rigid-plastic theory. The equivalence is in the sense of being with respect to probability of failure and is obtained by applying a random factor correction of the strength variables of the simple model. This model-correction factor is called the effectivity factor, and it is approximated to the zeroth order by a constant or to the first order by an inhomogeneous linear function of all the basic variables in the realistic model. The coefficients of this function are calculated from the elaborate model (e.g., by finite element calculations) with values of the input variables chosen on the basis of a first-order reliability analysis of the simple model (FORM). The model-correction-factor method is a special type of response-surface method based on mechanical principles. It is illustrated quantitatively on a yield hinge frame model with strain softening mutual rotation-moment behavior in the hinges upon the onset of yielding.

A texturization process was combined with response surface methodology to produce mango pulp with excellent aromatic qualities and high soluble dry matter content. Alginate was determined to increase the firmness of the texturized fruit products while the presence of calcium and glucono-delta-lactone increased the gel strength and thermostability of the mango pulp. These results indicated that texturized mango pulps with high soluble dry matter content may be produced using the above technique.

The effects of pH and dilution rate (D) on the growth of Ruminococcus flavefaciens FD-1 in continuous culture were studied using response surface analysis. Growth yield and cellulose digestion were concomitantly affected by pH and D. Cellulose consumption was more affected by D than by pH. Effects on cell yield showed that the effect of pH increased with increasing D. Soluble sugar concentrations were higher at lower Ds suggesting increased production due to longer retention time. Fermentation products consisted primarily of acetate, succinate and formate. Acetate production effects paralleled those of cellulose consumption and soluble sugar concentration.

A study was done on the relationships between gluten film-formation conditions and film properties. The combined effects of gluten concentration, ethanol concentration and pH of the film-forming solution on film opacity, water solubility, water vapor permeability and mechanical properties were also studied using response surface methodology. pH and ethanol concentration showed strong interactions which affect film opacity, solubility and water vapor permeability.