Order Polynomial Regression Equation Research Articles

Pengaruh Penggunaan Abu Cangkang Terhadap Kuat Tekan Beton

The background of this research is that there is still a lot of oyster shell material that has not been utilized, meanwhile the shell has good mechanical properties as well as concrete. Up to this moment, the shell is not used properly so it needs to studied the use as concrete mixture. By the utilization of this waste is expected to reduce the environmental impact. This study was aims to obtain a regression equation of the compressive strength of concrete using shells, the shells used in this study were oyster shells (ostreidae), tested at 28 days of age with 3 variations in the percentage of the use of shell ash material and with 1 variation of normal concrete. The percentage variations used are 0% variation, 5% variation, 10% variation, and 15% variation. In addition, based on the regression equation, the strong relationship between variables will be obtained which is indicated by the value of r square. The implementation of this research was carried out by carrying out a compressive test of concrete cylinder samples with 3 variations of the water cement rasio (W/C), is W/C 0.4, W/C 0.5, and W/C 0.6. The activity was continued by recording and analyzing data by conducting a regression analysis between the relationship between the percentage of shell use and the compressive strength of concrete. The regression equation used is the exponential regression equation, linear regression, polynomial regression order 2. From the test data, it is found that the regression equation is the best for W/C variation 0.4, obtained polynomial regression equation order 2, y = -0.0351x2 + 0, 3279x + 25.075 with r² = 0.9999, for the W/C variation of 0.5, the second order polynomial regression equation is obtained, y = -0.0702x2 + 0.8062x + 23.406 with r² = 0.8983, and for the W/C variation of 0.6 , the second order polynomial regression equation is obtained, y = -0.0404x2 + 0.4008x + 19.074 with a value of r² = 0.9167..

Buildability Analysis of 3D Concrete Printing Process: A Parametric Study Using Design of Experiment Approach

Plastic collapse and buckling are the key structural failure criteria in 3D concrete printing (3DCP). This study aims to analyze the effect of different geometrical designs and printing factors on the buildability performance of 3DCP structures. Due to the high number of variables involved, the Design of Experiment (DOE) has been used to reduce the number of simulations. In geometrical design parameters, the structure’s design is more sensitive, followed by the width and length of the printed design. The buildability increases when we move from sharp corners to more stable structures like fillets and circular geometry. For geometrical design parameters, a maximum buildability of 74% of the designed height is achieved for circular design with the highest width and lowest diameter. For printing parameters, the highest buildability of 486 mm (81%) is achieved for the lower values of printing speed and layer height. The study analyzed failure phenomena of buckling and yield strength for the tested combination of parameters. The study analyzed the sensitivity analysis of individual parameters and their combination for maximum buildability and developed the low order polynomial regression equation for each printing parameter and geometrical factors. Based on the analysis of the results, the study also proposed different new printing strategies to increase the overall performance of the printing process.

Investigation on the machinability of TiN nano particulate reinforced magnesium matrix composite

In the present work, the machinability of magnesium matrix nanocomposite was investigated. The nanocomposite consists of pure Mg as matrix and TiN Nano particulate as reinforcement. The composite was fabricated through powder metallurgy process for three different compositions such as 1.5, 2.5 and 5% by weight of TiN Nano particulates. Machinability behavior of the nanocomposite was studied through milling process with process parameters, feed rate of 5, 10 and 15 mm/min, depth of cut of 0.15, 0.3 and 0.45 mm and spindle speed of end mill remain constant of about 2000 rpm. The performance measures considered in this study are cutting forces, material removal rate, surface roughness and tool tip temperature. The milling process was carried out at room temperature for normal atmospheric conditions. Poly crystalline diamond (PCD) coated solid carbide flat type end mill was used in the study. L27 orthogonal array was used to conduct the experiments. The results from the study revealed the fact that the performance measures like cutting force, tool tip temperature and surface roughness are significantly influenced by TiN Nano particulate in the composite, whereas the material removal rate is greatly influenced by the machining parameter feed rate. High hardness, heat resistance and excellent wear resistance of TiN Nano particulate resulted in the influence of the performance measures. Main effect plots and interaction plots were generated for the performance measures which was further followed by ANOVA and second order polynomial regression equation to test the level of significance with least error.

Seamless topo-bathymetric surveys of Maiyegun Estate Waterfront Lagos State, Nigeria

Topo-bathymetric surveys are mostly desired in coastal area where water and land perpetually interact. This work explore the ground-based methods of topographic and bathymetric surveys in collecting data for the appropriate description of the Mayegun Estate water front and the adjoining land topography. To acquire depth data at pre-defined transects lines, hydrographic vessel and a trained diver were engaged. The topo-bathy DEM was produced at 1m and contour at 0.5m interval. The wave pattern was determined to be semi-diurnal. The fitted second order polynomial regression equation for wave amplitude against time yielded (y = 2E-07x2 - 0.0003x - 0.0276 at R² = 0.0064) while that of depth versus sounded points gave (y = 5E-09x2 - 5E-06x - 7.1512) at R² = 0.0019. The vertical and horizontal uncertainties were computed as 0.015m and 5m + (-0.47) at 95% confidence level based on (IHO) specification for order 1a. This principle can be adopted with caution as a viable alternative for topo-bathy surveys to minimize cost.

Оптимизация условий мицеллярно-ферментативной экстракции пектина из плодов боярышника ( Crataegus monogyna Jacq.)

Introduction. Commercial pectin is usually obtained from apples or citrus fruits. However, some wild fruits, such as hawthorn, are also rich in pectin with valuable nutritional and medical properties. The research objective was to study and improve the process of combined surfactant and enzyme-assisted extraction of pectin from hawthorn fruits.
 Study objects and methods. The study involved a 1% solution of Polysorbate-20 surfactant and a mix of two enzymes, namely cellulase and xylanase, in a ratio of 4:1. The response surface methodology with the Box-Behnken experimental design improved the extraction parameters. The experiment featured three independent variables – temperature, time, and solvent-to-material ratio. They varied at three levels: 20, 40, and 60°C; 120, 180, and 240 min; 15, 30, and 45 mL per g. Their effect on the parameters on the pectin yield was assessed using a quadratic mathematical model based on a second order polynomial equation.
 Results and discussion. The response surface methodology made it possible to derive a second order polynomial regression equation that illustrated the effect of extraction parameters on the yield of polyphenols. The regression coefficient (R2 = 98.14%) and the lack-of-fit test (P > 0.05) showed a good accuracy of the model. The optimal extraction conditions were found as follows: temperature = 41°C, time = 160 min, solvent-to-material ratio = 32 mL per 1 g. Under the optimal conditions, the predicted pectin yield was 14.9%, while the experimental yield was 15.2 ± 0.4%. The content of galacturonic acid in the obtained pectin was 58.5%, while the degree of esterification was 51.5%. The hawthorn pectin demonstrated a good complex-building ability in relation to ions of copper (564 mg Cu2+/g), lead (254 mg Pb2+/g), and cobalt (120 mg Co2+/g).
 Conclusion. Combined surfactant and enzyme-assisted extraction made improved the extraction of pectin from hawthorn fruits. The hawthorn pectin can be used to develop new functional products.

Coagulation kinetic study and optimization using response surface methodology for effective removal of turbidity from paint wastewater using natural coagulants

The wastewater from paint manufacturing industry contains high quantity of pollutants that are generated from washing equipment, as well as chemical additives. Hence, coagulation–flocculation was applied in the present study to evaluate the performance of some natural coagulant derived from Hibiscus esculentus L,(okra) Detarium microcarpum,(sweet dater) Xanthosoma (cocoyam) and Crassostrea Virginica, (oyster shell) in the removal of turbidity from paint wastewater (PW). The coagulants were characterized using Fourier transform infrared spectrometer (FTIR), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). A laboratory jar test was employed for the experiments. Process kinetic was studied to determine coagulation-flocculation parameters such as coagulation rate constant and coagulation half-life τ1/2. The effects of the operating parameters such as initial pH of the wastewater, coagulant dosage and settling time affecting the efficiency of turbidity removal were studied in a one-factor-at-a-time (OFAT) process. Box-Behnken Design (BBD) was used in designing the experiment; evaluate the individual and interactive effect of the variables and determining the optimum conditions. Statistical parameters such as coefficient of determination R2, sum of square roots due to error (SSE) and the root mean square error (RMSE) were used to evaluate the adequacy of the process. The optimum removal of turbidity was observed at pH range 2–4, dosage 100–200 mg/L and settling time of 30 min for the coagulants, with removal efficiency of 60–92.6% a second order polynomial regression equation with R2 values of 0.9644, 0.9827, 0.9707 and 0.9718 for OSC, DMC, CYC and ODC, respectively. While the coagulation half-time, τ1/2 ranges from 0.98 for OSC, 0.87 for DMC, 13.73 for CYC and 9.15 for ODC. The study has proved the coagulant can be used in treatment of turbidity from paint wastewater.

Effects of fermented Broussonetia papyrifera on growth, intestinal antioxidant, inflammation and microbiota of grass carp (Ctenopharyngodon idella)

The present study was conducted to investigate the influence of fermented Broussonetia Papyrifera (FBP) on growth performance, intestinal antioxidant capacity, inflammation and microbiota of grass carp. Fish (initial weight: 50.0 ± 0.5 g) were fed diets with 0 (control diet), 5 % (FBP5), 10 % (FBP10), 15 % (FBP15) and 20 % (FBP20) of FBP supplementation respectively for 8 weeks. The results showed that FBP5 group significantly decreased FCR of grass carp (P < 0.05). Besides, FBP supplementation significantly decreased intestine Cu/Zn SOD activity (P < 0.05), as well as significantly elevated mRNA expression level of kelch-like-ECH-associated protein 1 (keap1) and depressed mRNA expression level of NF-E2-related factor 2 (nrf2), superoxide dismutase 1 (sod1) and catalase (cat) (P < 0.05). The content of malondialdehyde (MDA) increased significantly in the FBP20 group compared to the control diet (P < 0.05). The expression level of interleukin-8 (il-8) and interferon γ (ifnγ) downregulated with increased dietary FBP, and significant difference was found in FBP20 group (P < 0.05). In addition, when the supplementation of FBP was no more than 15 %, the abundance of Firmicutes and Fusobacteria increased significantly, while the abundance of Actinobacteria and Cyanobacteria decreased significantly in intestine of grass carp (P < 0.05). Compared to the control diet, the richness and diversity of intestinal microbiota of grass carp decreased significantly in FBP20 group (P < 0.05). According to the second order polynomial regression equation analysis of SGR and FCR, the optimal additional level of FBP was estimated to be 4.58 % and 5.28 %, respectively. The recommended maximum addition of FBP in diet of grass carp was up to 15 % according to the results of intestinal microbiota.

Design, Fabrication, Evaluation and Calibration of an Improvised Soil Permeameter for Measurement of Soil Hydraulic Conductivity

This study aimed at the design, fabrication, evaluation and calibration of an improvised soil permeameter for measuring saturated soil hydraulic conductivities. A metal support frame with a permissible strength of 50e-4 N/mm2 was made using steel galvanized pipes of 6 cmØ (internal diameter) and metal flat bars of 8cm long and 0.4cm thick. The water tank (thickness 0.6 cm, height 28 cm, internal diameter 19 cmØ) and permeameter cylinder (thickness 0.6 cm, height 23 cm, internal diameter 19 cmØ) were both made of Perspex glass material. An electromechanical measuring device which was programmed and operated wirelessly was designed and constructed to measure head-in and head-out parameters. To calibrate the improvised soil permeameter, sampled and particle analysed soils from different locations within Zaria metropolis, were a test run on both foreign and improvised soil permeameters and their respective Ksat readings were subjected to regression analysis. According to the R2 values, the generated 3rd order polynomial regression equation from the Ksat readings of both foreign and improvised soil permeameter had a satisfactory R2 value of 0.985.&#x0D; Keywords: Permeameter, Hydraulic Conductivity, Electromechanical, Saturated, Automation

Effects of dietary lipid levels on survival, growth performance, and antioxidant ability of the early juvenile Scylla paramamosain

Five isonitrogenous diets (50% crude protein) with 7%, 9%, 11%, 13%, and 15% lipid levels (named as L7, L9, L11, L13, and L15, respectively) were designed to evaluate the effects of dietary lipid levels on survival, growth performance, body composition, and antioxidant ability of the early juvenile Scylla paramamosain. Each diet was fed to three replicates of 28 crabs with initial weight 42.23 ± 0.21 mg for 8 weeks. Crabs fed diet with lowest dietary lipid level (L7 group) obtained significantly lower survival than other crabs. The highest final body weight (FBW), weight gain (WG), specific growth rate (SGR), and molting frequency (MF) were observed in L11 group. Meanwhile, the highest mRNA expression of ecdysone receptor (EcR) also observed in L11 group. Besides, a positive correlation between body lipid contents and dietary lipid levels was observed in present study. But the mRNA expression of fatty acid synthetase (FAS) was relatively lower in L15 group. In the hepatopancreas, superoxide dismutase (SOD) activity significantly increased with increasing dietary lipid levels. On the contrary, the concentration of malondialdehyde (MDA) significantly decreased with elevating dietary lipid levels (except L15 group). Meanwhile, the lowest catalase (CAT) activity appeared in L7 group, but there was no statistical difference from other groups. Through the second order polynomial regression equation analysis of WG, the optimum dietary lipid level in the early juvenile S. paramamosain was 10.31%.

Response Surface Modeling and Optimization of Polyphenols Extraction from Apple Pomace Based on Nonionic Emulsifiers

The factors affecting the efficiency of micelle-mediated extraction of phenolic compounds from apple pomace was investigated. Higher extraction efficiency by using as a solvent an aqueous solution of Tween 80 in comparison to Triton X-100, Span 20, Tween 20, 70% ethanol, and water was shown. Four independent variables (Tween 80 concentration, time, solvent-to material ratio, and pH) to enhance the recovery of polyphenols from apple pomace was investigated. Applying response surface methodology, the second order polynomial regression equation showing dependence of the yield of polyphenols on the extraction parameters was derived. The adjusted regression coefficient (R2 = 98.73%) and the lack-of-fit test (p &gt; 0.05) showed a good accuracy of the developed model. The difference between observed and predicted values was no more than 3%. The optimal extraction conditions were found to be Tween 80 concentration of 1.14%, time of 65 min, solvent-to-material ratio of 104 mL g−1, pH of 3.8. Under optimal conditions the predicted total phenolic compounds content was 7.75 mg g−1. The obtained apple pomace extracts were characterized in terms of their antioxidant activity. The proposed extraction technology by using Tween 80 aqueous solution as a solvent allows obtaining the extracts with high content of polyphenols which are suitable for the applications in food, cosmetic, and pharmaceutical products requiring a surfactant to stabilize them.

REMOVAL OF Ni2+ FROM AQUEOUS SOLUTION BY ADSORPTION ONTO TEA WASTE–DERIVED ACTIVATED CARBON

Activated carbon from a locally available and widespread tea waste source was fabricated, characterized and used as an efficient adsorbent for the removal of Ni2+ from aqueous solutions. The response surface methodology (RSM) and central composite design (CCD) were used to investigate the effect of the essential variables including initial concentration, adsorbent dosage and pH solution on the absorption of Ni2+. The order polynomial regression equations–based model has been developed and found to be statistically significant by values of the coefficients of determination (R2) closer than 1.0 and the P–values &lt; 0.0001 from analysis of variance (ANOVA). Based on the predicted optimum conditions, actual experiment was employed to obtain the maximum percentage of Ni2+ removal efficiency (96.6 %). There is no doubt that the use of tea waste as abundant raw material for the preparation of activated carbon to remove Ni2+from aqueous solutions by five times with negligible change is a promising way.

Optimization of Extrusion Variables for Improving the Qualities of Textured Vegetable Protein with Green Tea Using Response Surface Methodology

The aim of this study was to evaluate the optimization extrusion variables on quality of textured vegetable protein by using response surface methodology. In this study, 50% soy protein isolate, 40% wheat gluten, and 10% corn starch were blended and 15% of the mixture was substituted with green tea. The moisture content (45, 50, and 55%), barrel temperature (130, 140, and 150oC), and screw speed (100, 150, and 200 rpm) were varied. A Box- Behnken design was used in this experiment. Second order polynomial regression equations were developed to relate the response to extrusion variables as well as to obtain a response surface plot. The independent variables had significant effects on the quality of the products and moisture content was the most significant. The lower moisture content led to the higher integrity index, lower nitrogen solubility index, lower water absorption capacity, higher texture, and higher cutting strength. The optimum conditions were identified as moisture content 47.78%, barrel temperature 150.00oC, and screw speed 196.05 rpm. Incorporation of green tea into protein materials could effectively improve the nutritional value of the product. Understanding these optimized extrusion variables on the product quality was useful for producing textured vegetable protein in the future.

Sensitivity Analysis for Process Parameters in Cladding of Austenitic Stainless Steel by Pulsed Metal Inert Gas Welding Process

In recent scenario, the automation in weld cladding process has a challenging task for most of the industries like automotive, petrochemical and food processing industries. Because to achieve the best quality of the weld clad bead geometry during automated process it is important to have complete control over the selected process parameters. The cladding process enhances the base material properties. Therefore, it is essential to predict the relationship between the process parameters and response the second order polynomial regression equation has to be developed. It makes more effectiveness of automated weld cladding processes. Palani and Murugan [1] developed a mathematical model for a flux cored arc welding process using an RSM method to study the direct effects and interaction effects of process parameters on clad bead geometry.

Assessing the combined effects from two kinds of cephalosporins on green alga (Chlorella pyrenoidosa) based on response surface methodology

The present work evaluated the combined effects of cefradine and ceftazidime on the green alga Chlorella pyrenoidosa using response surface methodologies (RSM). After a 48 h-exposure, the population growth rate (PGR), the chlorophyll-a content and the SOD content of the alga increased with increased concentrations of two antibiotics. However, the three responses did not continue to demonstrate significant increases once antibiotic concentrations exceed a moderate level. Three two order polynomial regression equations were obtained to describe well the relationship between the responses of the alga and the two antibiotics' concentration (R2 = 0.9997, 0.9292 and 0.9039, respectively). Three 3 D-surface graphs and their contour plots showed directly the changing trends of the alga under the combined effects of two antibiotics. This study for the first time employed the RSM in ecotoxicology, which indicated that the RSM should be placed under a feasible and a potential application prospect in toxicity assessment.

Monitoring urbanization dynamics in India using DMSP/OLS night time lights and SPOT-VGT data

India is a rapidly urbanizing country and has experienced profound changes in the spatial structure of urban areas. This study endeavours to illuminate the process of urbanization in India using Defence Meteorological Satellites Program – Operational Linescan System (DMSP-OLS) night time lights (NTLs) and SPOT vegetation (VGT) dataset for the period 1998–2008. Satellite imagery of NTLs provides an efficient way to map urban areas at global and national scales. DMSP/OLS dataset however lacks continuity and comparability; hence the dataset was first intercalibrated using second order polynomial regression equation. The intercalibrated dataset along with SPOT-VGT dataset for the year 1998 and 2008 were subjected to a support vector machine (SVM) method to extract urban areas. SVM is semi-automated technique that overcomes the problems associated with the thresholding methods for NTLs data and hence enables for regional and national scale assessment of urbanization. The extracted urban areas were validated with Google Earth images and global urban extent maps. Spatial metrics were calculated and analyzed state-wise to understand the dynamism of urban areas in India. Significant changes in urban proportion were observed in Tamil Nadu, Punjab and Kerala while other states also showed a high degree of changes in area wise urban proportion.

Application of response surface methodology to evaluate stone matrix asphalt stripping potential

Stone matrix asphalt mixes are widely used in Western Europe due to its high strength properties in pavements, this type of mix is subjected to continuous wetting and drying cycles due to its porous structure leading to a higher potential for stripping. Lime has long been recognized and used in industry to reduce the stripping potential of SMA. Aggregate grading has also been identified to have an impact on the moisture damage potential. Response surface methodology was employed in this paper to evaluate the effect of lime content and grading on stripping potential of Stone Matrix Asphalt (SMA) using Tensile Strength Ratio (TSR) index. The statistical significances of linear, quadratic and interactive terms of the lime percent and grading were examined and second order polynomial regression equation was successfully fitted to the experimental results. The lime content of 1% and the finest aggregates resulted in a TSR optimum value of 91.8%±0.8%. It was further concluded that increasing the mastic asphalt would decrease the stripping potential of SMA and both of the two parameters evaluated, had approximately the same main effect on the TSR response.

Protein rich extruded products prepared from soy protein isolate-corn flour blends

Protein rich extruded products were prepared from soy protein isolate and corn flour blends using a twin screw extruder and the physical properties of the extruded product were evaluated and related to process variables: soy protein isolate (SPI) (32.2–66.6 g protein/100 dry matter), feed moisture (31.6–48.4 g/100 g) and process temperature (126.4–193.6 °C). A central composite rotate design (CCRD) and response surface methodology was used to evaluate the significance of independent and interaction effects of extrusion process variables on the product’s various physical properties (breaking stress, bulk density, expansion ratio, water solubility index, rehydration rate and color). Second order polynomial regression equations were developed to relate the product responses to process variables as well as to obtain the response surfaces plots. The independent variables had significant (p ≤ 0.05) effects on physical properties of extrudates: (i) higher SPI and feed moisture contents increased the breaking stress and bulk density, but decreased the expansion ratio, water solubility index, and rehydration rate, (ii) higher SPI content decreased the color L value, whereas higher feed moisture content increased it, (iii) higher temperatures increased breaking stress, expansion ratio, rehydration rate and L value, but decreased the bulk density and water solubility index.

Simplification and optimization of deMan Rogosa Sharpe (MRS) medium for enhanced production of bacteriocin by Weissella paramesenteroides DFR-8.

Complex growth medium such as deMan Rogosa Sharpe (MRS) medium, commonly used for cultivation of fastidious lactic acid bacteria (LAB) interfere in bacteriocin purification. Sometimes all the ingredients of a defined medium are not required by all LAB strains for bacteriocin production. In the present study, composition of the MRS medium for the production of bacteriocin by Weissella paramesenteroides DFR-8, an isolate from cucumber (Cucumis sativus), was simplified and optimized with a step-wise strategy. In the first step, production profile, effect of incubation temperature, various C and N sources were investigated. In the second step, central composite rotatable design was employed to decide the optimal concentration of 3 key components (glucose, tryptone and pH) and the experimental results were fitted with a second order polynomial regression equation. According to the set criteria, the predicted bacteriocin titer from a medium containing 7.99% glucose, 9% tryptone, pH 7.5 (91.9% desirability) was 540 AU/ml and the observed bacteriocin titer was 538 AU/ml that indicated the validity of the developed model. Using optimized medium, bacteriocin titer of 674.5 AU/ml could be achieved after 72 h of fermentation that is nearly 2.5 fold higher than that obtained from unmodified MRS medium.

Influence of Pulping Conditions on the Properties of Anatolian Black Pine (Pinus Nigra Arnold SSP. Pallassiana) Kraft Pulps

ABSTRACTAnatolian Black Pine wood chips were pulped using kraft method in laboratory scale batch digester. A series of experimental kraft pulping was carried out according to Central Composite Design (CCD) to investigate the pulping process and to study the effect of its variables (active alkali rate, sulphidity rate and Vroom's H-factor combining temperature and time) on pulp quality and yield. Second order polynomial regression equations using three independent process variables, were found to be approprite for describing kraft pulping of Anatolian Black Pine wood fibers. The derived equations were able to predict the kappa number, viscosity, yield, holocellulose and α-cellulose content of the pulp with adjusted R2 values of 96.1%, 96.8%, 86.3%, 62.5%, 96.1% and 92.2% respectively. H-factor level and the active alkali charge are the most strongly influcing all the dependent variables. In order to obtain acceptable levels of the pulp properties, high sulphidity rate (45%), medium H-factor (1600) and medium alkali concentration (18%) can be used in kraft pulping of Anatolian Black Pine woods.

EFFECT OF SOIL CONDITION ON THE ROOT CONTRACTION OF GINSENG

EFFECT OF SOIL CONDITION ON THE ROOT CONTRACTION OF GINSENG