Graphical Optimization Research Articles

Advanced Exergy-Based Optimization of a Polygeneration System with CO2 as Working Fluid.

Using polygeneration systems is one of the most cost-effective ways for energy efficiency improvement, which secures sustainable energy development and reduces environmental impacts. This paper investigates a polygeneration system powered by low- to medium-grade waste heat and using CO2 as a working fluid to simultaneously produce electric power, refrigeration, and heating capacities. The system is simulated in Aspen HYSYS® and evaluated by applying advanced exergy-based methods. With the split of exergy destruction and investment cost into avoidable and unavoidable parts, the avoidable part reveals the real improvement potential and priority of each component. Subsequently, an exergoeconomic graphical optimization is implemented at the component level to improve the system performance further. Optimization results and an engineering solution considering technical limitations are proposed. Compared to the base case, the system exergetic efficiency was improved by 15.4% and the average product cost was reduced by 7.1%; while the engineering solution shows an increase of 11.3% in system exergetic efficiency and a decrease of 8.5% in the average product cost.

Optimal TIG Welding Parameters of Dissimilar Aluminum Alloys 7075 and Al 6061 Using Ultrasonic Vibration and Nanocomposite Filler (Al 5356/ZrB2) to Alleviate Hot Cracking Phenomenon

Abstract In this study, the welding of dissimilar aluminum alloys, Al 7075 and Al 6061, was investigated using Al 5356 filler rods reinforced with ZrB2 particles. The welding process was conducted using TIG welding, with and without ultrasonic vibration, to enhance weld quality and reduce hot cracking. Optimization of process parameters for dissimilar TIG welding was performed through Response Surface Methodology (RSM), which generated a design matrix to analyze the influence of process parameters on response variables. Numerical and graphical optimization were applied to minimize hot cracking sensitivity and maximize microhardness. The RSM-based models suggested an optimal welding current of 93A, the use of Al 5356/ZrB2 nanocomposite filler, and the application of ultrasonic vibrations. Experimental validation of the identified solution demonstrated improvements in weld quality, including increased yield strength and ductility. The combination of nano-reinforced fillers and ultrasonic vibrations was found to enhance weldability and mitigate hot cracking in dissimilar aluminum joints. The mechanism of hot cracking reduction involved grain refinement, degassing, and homogenization due to ultrasonic vibrations, as well as the modification of weld pool chemistry and control of dilution by the nanocomposite filler, which collectively minimized solidification shrinkage and stress. Under these optimized conditions, no hot cracking was observed experimentally.

​Statistical-based optimization and mechanism assessments of Arsenic (III)​ adsorption by ZnO-Halloysite nanocomposite​

Arsenic contamination in aqueous media is a serious environmental problem, especially in developing countries. In this research, the Box-Behnken response surface methodology was used to optimize the most relevant variables affecting arsenic adsorption on the ZnO-halloysite surface, including temperature, adsorbent dosage, pH, contact time, and As (III) initial concentration. The regression analysis indicated that the experimental data were appropriately fitted to a quadratic model with the adjusted R-squared value (R2) of 0.982 for As(III) adsorption capacity and a linear model with R2 of 0.931 for As(III) removal. The p-values for both adsorption capacity and removal efficiency were below 0.05, with F-values of 116.91 and 115.58, respectively, supporting the model’s validity. The optimum conditions for maximum removal of As(III) were determined through numerical and graphical optimization using the desirability function. It was found that the optimum conditions for adsorption were pH = 7.99, contact time of 3.99 h, As(III) initial concentration of 49.96 mg/L, and adsorbent dosage of 0.135 g/40 ml. The accuracy of the optimization procedure was confirmed by a confirmatory experiment, which showed a maximum arsenic removal of 91.31% and an adsorption capacity of 12.63 mg/g under optimized conditions. Moreover, XPS analysis was performed at different pH levels to investigate the As (III) adsorption mechanism. The results demonstrated that As(III) adsorption occurs at acidic and neutral pH levels. On the other hand, when pH is increased to 8, As (III) oxidizes to As (V), and then adsorption occurs.

Optimization of Alkali Treatment Conditions of Ramie Fabrics Using Box–Behnken Method

Ramie is a widely used plant fiber for making textiles and reinforcement in biodegradable composites. Pretreating cellulosic fibers with alkali before producing composites is increasingly used to enhance adhesion with polymeric resin. In this work, response surface methodology (RSM) based on the Box-Behnken technique was utilized to investigate the impact of independent variables on ramie fabric characteristics and determine the optimal treatment condition. The impact of alkali concentration, treatment time, and temperature on the breaking load and elongation at break of woven ramie fabrics were evaluated using Design-Expert software, which established the design matrix and analyzed the experimental data employing numerical and graphical optimization methods. Moreover, the impact of alkali treatment conditions on the surface morphology, structural change of ramie fabrics, and thermal properties was investigated. Based on the analysis of variance (ANOVA) results, the suggested quadratic models can adequately predict the breaking load and elongation at break of the ramie woven fabrics within the range of conditions applied in this investigation. The RSM revealed that an alkali concentration of 6.12%, a treatment time of 30 min, and a temperature of 39.13°C resulted in an optimum treatment condition with a breaking load of 518.28 N and elongation at break of 23.36%.

Multiresponse Optimization of Value-Added Sesame Seed Candy

Sesame seed candy, traditionally produced from sesame seeds and sugar, is a confection. This study focuses on the optimization of value-added sesame seed candy from sesame seed, ginger, cinnamon, and honey employing numerical and graphical optimization, via desirability function technique. Experiments were conducted using a four-component constrained D-optimal mixture-process experimental design and the formulated candies were characterized. The formulation design constraints were: sesame seed (40 – 70%), ginger (10 – 30%), cinnamon (10 – 30%), honey (10 – 30%); while the processing factor were roasting temperature (100 – 150 ) and roasting time (10 – 30mins). Consumer acceptability was measured by 50 semi-trained regular consumers using a 9-point hedonic scale. The formulation that produced optimal candy of the highest desirability index of 0.506 was 43.53% sesame Seed,10% ginger, 16.47% cinnamon, and 30% honey, with 110 roasting temperature. and .27 min mixing time. The quality properties of the optimal value-added sesame seed candy were 7.95% moisture content, 20.76% dietary fibre, 37.89% protein, 10.40% carbohydrate, 17.20% fat content, 249.71mg calcium, 0.029mg/100g vitamin C, 353.54kcal energy value, 5.78 hardness, 6 taste, 5.74 colour, 5.87 chewiness, 5.92 gumminess, 5.6 crispness, 6.11 flavour, and overall acceptability of 6.20; based on 9-point hedonic scale. Sesame seed, the major ingredient in the candy production, has a composition of about 50 – 52% oil, 17-19% protein, 48.5% crude oil, 9.4% crude fibre, 4.2% ash. and 16-18% carbohydrate. Compared with the traditional sesame seed candy, the optimal value-added sesame seed candy was of higher quality.

Development of optimal L-PBF process parameters using an accelerated discrete element simulation framework

Laser Powder Bed Fusion (L-PBF) has immense potential for the production of complex, lightweight, and high-performance components. The traditional optimization of process parameters is costly and time-intensive, due to reliance on experimental approaches. Current numerical analyses often model single-line scans, while it is necessary to model multiple fully scanned layers to optimize for bulk material quality. Here, we introduce a novel approach utilizing discrete element simulations with a ray tracing-modeled laser heat source. Our approach significantly reduces the cost and time consumption compared to conventional optimization methods. GPU acceleration enables efficient simulation of multiple layers, resulting in parameters optimized for bulk material. In a case study, parameters were optimized for AlSi10Mg in just 5 days, a process that would have taken over 8 months without GPU acceleration. Experimental validation affirms the quality of the optimized process parameters, achieving an optical density of 99.91%.Graphical Optimization using the accelerated simulation yielded an optimized parameter set within 5 days. This resulted in apart with an optical density of 99.91%.

DEVELOPMENT AND OPTIMIZATION OF RABEPRAZOLE CHRONO-MODULATED DRUG DELIVERY SYSTEMS

Objective: Development and optimization of chrono-modulated pulsatile drug delivery systems (CPDDS) loaded with Rabeprazole for treating nocturnal acid breakthrough in ulcer patients was set as the major objective of this work. Methods: CPDDS were developed to provide drug release as two pulses with predetermined gap. Separate microparticles for delayed instant release (DIR) and delayed extended-release (DER) were formulated. Through the optimization of several formulation and process parameters, ER microparticles were created as matrix microspheres. Central composite design was used to understand how the factors affected the responses. The optimized ER microspheres and plain drug were separately subjected to enteric coating to obtain DER and DIR portion microparticles, respectively. Results: With the exception of stirring speed's impact on drug release, every other factor was found to have a significant influence (p<0.05) on every response. The mechanism underlying the Rabeprazole's delayed prolonged release was explained by the SEM images. The microspheres made with Eudragit RSPO at 0.72 g and polyethylene oxide at 0.5 g for 1 g of Rabeprazole at 400 rpm were shown to be the optimal formulation based on the graphical optimization results. After being coated with a terminal enteric coating, this formulation showed delayed release for a duration of 6 h. Conclusion: After oral administration of equal doses of DIR microcapsules along with the optimized DER microspheres could release Rabeprazole effectively as two different pulses at the desired time intervals.

Optimization models for photosynthetic bioenergy generation in building façades

Façade design optimization has a significant impact on promoting resilient solar harvesting methods in urban areas. This study introduces a new framework toward the optimal inclusion of microalgae photobioreactors in different façade geometries by developing a detailed chemical kinetics model aided by optimization techniques. Although algal bioreactive façades in recent literature are restricted to flat façades, the present study reveals that bioenergy generation can be enhanced by up to 29.6 % through optimized folded façades. Hooke-Jeeves algorithm demonstrates remarkable computational efficiency in optimizing such façades, achieving the optimal outcome with only 88 function evaluations. However, the Hooke-Jeeves algorithm has limitations when applied to free-form façades by displaying noticeable instability and reporting an optimal value approximately 40 % lower than Genetic Algorithms. Hooke-Jeeves algorithm has the possibility to conclude misleading outcomes as optimal points. This is mitigated by applying multiple initial points and verifying the outcomes with graphical optimization. In terms of energy performance, free-form façades have higher irradiation of up to 210 W/m2 compared to 180 W/m2 for flat façades. Optimal distribution of renewable modules on free-form façades increases energy generation by 14.3 %. South-facing façades produce the highest bioenergy at 2.4 W/m2, while west and east orientations generate the lowest at 0.8 W/m2.

Optimization of Blending Ratio of Emmer Wheat Flour, White Sesame Powder and Sweet Potato Leaves Powder to Produce Nutrient-Dense and Sensory Acceptable Gruel

ABSTRACT This study focuses on optimizing the blending ratio of Emmer Wheat Flour (EWF), White Sesame Powder (WSP), and Sweet Potato Leaf Powder (SPLP) to improve the nutritional and sensory properties of gruel for children up to 2 years of age. Thirteen formulations were created with the help of D-optimal mixture design (Minitab Ver. 19.2), considering EWF (70–80%), WSP (10–20%), and SPLP (5–10%). The resulting gruel underwent analysis for proximate, mineral, functional, anti-nutritional, and sensory properties. Graphical optimization revealed that a blend of 71.30% EWF, 20% WSP, and 8.70% SPLP yielded nutrient-enriched gruel with high sensory acceptability (Desirability: 0.85). This optimized gruel contains essential nutrients, including fat (8.35%), protein (15.058%), fiber (8.27%), carbohydrates (62.073%), energy (425.91 kcal/100 g), and minerals (Fe: 9.17, Zn: 3.79, Ca: 393.027 mg/100 g). Overall, the study concludes that EWF, WSP, and SPLP-based gruel can effectively address protein-energy malnutrition and iron deficiency in infants. Novelty Impact Statement Preparation of gruel from the locally available and cost-effective materials are considered in this study. Preparation of the gruel from the emmer wheat, sesame powder and sweet potato leaves powder is not reported yet. The SPLP is rich in different nutrients, and they are the waste produced in the production system. So, using these locally available ingredients to alleviate malnutrition is very important.

Optimal Design of Tilted Building Envelope Considering Air Conditioning Energy Demand, Daylight Utilization and Glare Protection—Case Study

An important energy-saving method to optimize building envelope design is the integration of local climate characteristics. This study attempts to find sloped facade configurations to balance air conditioning energy demand and daylight utilization for four directions in an area with a hot climate. Tilt angle dependence of the air conditioning energy demand, useful daylight illuminance (UDI) and daylight glare index (DGI) are selected to investigate the acceptance thresholds of the tilt angle. The final facade’s configuration is achieved by employing the graphical optimization method. An acceptable solution that balances better daylight performance and less energy consumption by air conditioning is developed. Due to the considered city being located in a low-latitude area with great daylight availability as well as a fully dimmable light control strategy, unbearable glare reduction can be achieved by benefiting from the sloped facades, without necessarily sacrificing much usable daylight. Meanwhile, there is no obvious increase in the demand for lighting energy consumption, and a good outward view is preserved. The sloped rather than vertical facade provides natural solar shading to the east-, south- and west-oriented windows while allowing low-angle winter solar heat to warm the building space. Tilt angles between 35°and 40° are preferred for the east facade, and smaller tilt angles of between 30°and 35° are recommended for the south facade. Larger tilt angles of between 40°and 45° are preferred for the west facade. However, the north-facing facade’s outward tilt would cause an undesirable increase in air conditioning energy demand. The annual air conditioning energy demand of the east-, south- and west-facing space is found to separately decrease by 7.1%, 7.3% and 9.9%, respectively, benefiting from the sloped facades.

Application programming interface for electron beam welding of Inconel 718 thin plates

In this paper the simulation of electron beam welding of Inconel 718 thin plates by a moving linear heat source is considered. Neural network models are developed and used for the description of the dependence of the molten pool geometry characteristics on the process parameters - electron beam power, welding velocity, and the plate thickness. Neural network models, based on a multi-layered feedforward neural network, trained with Levenberg-Marquardt error backpropagation algorithm are compared with estimated regression models. The neural networks are trained, tested and validated using a set of experimental data. The resulting models are implemented for developing of an application programming interface for electron beam welding of Inconel 718 thin plates, which is used for prediction, investigation and graphical optimization of the molten pool geometry characteristics of the obtained electron beam welds.

Optimal parameters for producing ferrosilicon from a mixture of diatomite and opoka

In view of the limited reactivity of crystalline silica used in the production of ferrosilicon, it is necessary to search for silica-containing raw materials that have this property to a higher degree. The article presents the results of studies on the production of ferrosilicon from a mixture of amorphous silica-containing rocks – opoka and diatomite in a 1:1 ratio in the presence of coke and steel shavings. The studies have included the electric smelting of the charge in a single-electrode arc furnace and using the second-order rotatable designs of experiments (Box-Hunter plans) followed by graphical optimization. The research has established that FeSi25 (24.5-30% of Si), FeSi45 (41-47% of Si), and FeSi50 (47-51% of Si) grades of ferrosilicon can be smelted from a mixture of diatomite and opoka, depending on the amount of coke and steel shavings. The optimal parameters for producing FeSi25 ferrosilicon (with the extraction of 80-82.4% of silicon into the alloy) were 35.0-37.2% of coke and 33.75-35.0% of steel shavings. FeSi45 ferrosilicon (with extraction of 80-84.6% of silicon) was formed with 38.0-45.0% of coke and 29.2-33.2% of steel shavings. At 40.4-45.0% of coke and 29.2-31.1% of steel shavings, FeSi50 ferrosilicon was formed; the extraction of silicon into the resulting alloy was more than 80-81.5%. At the balance electric smelting of the diatomite and opoka mixture in the presence of 45% of coke and 30% of steel shavings, ferrosilicon of FeSi50 grade (51.8-52.6% of Si) was produced with the 82% silicon extraction degree.

Literature Review of Mixed Reality Research

The global evolution of mixed reality, driven by recent technological advancements, promises to transform industries and daily life by enhancing functionalities and services. This short review assesses highly cited papers over the last two decades from an over a thousand of research papers on mixed reality. Emphasizing papers published in 2022 and 2023, it delves into the contemporary applications of mixed reality, highlighting its potential in digitally enhanced simulations and utilities amidst the expansive language model era. Additionally, the review examines both the possibilities and constraints of these innovative solutions, shedding light on emerging research domains like education, telemedicine, remote control, and graphics optimization in real-time rendering.

Optimization of Coffee-Gelatin Shot Formulations Based on Physicochemical, Rheological and Sensory Properties Using Response Surface Methodology

The objective of this study was to optimize the coffee content and alcohol content of the formulations of coffee-gelatin shots based on physicochemical, rheological and sensory properties of the products. Because the coffee content and alcohol content influenced those properties of coffee-gelatin shots significantly which were related to the consumers’ acceptance. Thirteen different coffee-gelatin shots for nine formulations based on CCRD were developed and the sensory properties (overall acceptability, color, flavor and texture), L-value, pH and viscosity of coffee-gelatin shots were determined. The regression models were developed to predict the response variables as a function of independent variables. The response surface models were developed to understand the effects of independent variables on the responses. A desirability function was used to determine an optimum formulation using a numerical optimization technique. All contour plots of response surface models were superimposed to visualize an optimum region. The regression models could predict the sensory properties, L-value, pH and viscosity of coffee-gelatin shots as a function of coffee content and alcohol content with an accuracy of 77-99% depending on the properties of coffee-gelatin shots. The coffee content and alcohol content affected the sensory properties, L-value and viscosity of coffee-gelatin shots significantly (p<0.05). The optimization results obtained using numerical and graphical optimization techniques indicated that a combination of coffee (2.50 -3.00 g) and alcohol (5.25-6.75 mL) was the optimum formulation of a coffee-gelatin shots that improved the sensory properties, L-value, pH and viscosity of the coffee-gelatin shots. This optimum formulation of coffee-gelatin shots is expected to be useful for commercial manufacturing of consumers’ desired coffee-gelatin shots.

The effect of extrusion condition and blend proportion on the physicochemical and sensory attributes of teff-soybean composite flour gluten free extrudates

The effects of soybean-to-teff ratio (SB), feed moisture content (FM) and barrel temperature (BT) on physico-chemical properties and sensory attributes of extruded product from teff-soybean flour blend was studied. Increase in BT resulted in increase in expansion ratio(ER), water absorption index (WAI), and water solubility index (WSI) whereas the bulk density (BD) and hardness decreased with increase in BT. Increase in the proportion of SB resulted in increased BD, hardness, and reduced water solubility index (WSI) and sensory scores. Three principal components explained 89.1 % of the variations where the first (PC1), the second (PC2) and the third (PC3) principal components explained 62.4, 20.2 and 6.5 % of the variations respectively. BD, WAI and Hardness are strongly and positively associated with each other whereas they are negatively associated with WSI, crispiness, Specific length (Lsp) and ER. Graphical optimization gave best results for BT between 128 and 137 °C and SB proportion between 2 and 7.3 % where the FM is fixed at 10 %. Besides, BT of 135 °C to137 °C, FM of 10–12 % when the SB proportion is fixed at 7.5 % gave optimal product quality. The numerical optimization resulted in optimal extrusion conditions for optimal product quality were BT of 135 °C, FM of 10 % and SB proportion of 5 % with a desirability value of 0.875. The results revealed that SB can be incorporated up to 7.5 % to obtain an acceptable product. Therefore it is possible to produce gluten-free extruded snack by blending teff and soybean flour.

Quality by Design-driven Development of 5-fluorouracil Loaded Mucoadhesive Microparticulate Drug Delivery Systems for Effective Chemotherapy for Colorectal Cancer

Aims: To enhance oral bioavailability and decrease the dosing frequency of 5-Fluorouracil Background: Cancer is one of the most dreadful diseases for which complete cures are not possible, but colorectal cancer is completely curable if diagnosed at an early stage. If diagnosed in late-stage, 5-Fluorouracil (5-FU) is mostly recommended for its effective treatment, but the challenges associated with this drug are short elimination half-life, severe side effects, as well as non-specificity. The challenges can be better addressed by fabricating microbeads using the QbD approach. To enhance the oral bioavailability of 5-FU and to target the colon for the effective treatment of colorectal cancer, the microbeads were fabricated by emulsification crosslinking method using Box-Behnken design. Objective: To target the colon for effective treatment of colorectal cancer with enhanced oral bioavailability. Methods: The microparticulate drug delivery system was fabricated by using the emulsification crosslinking method by implementing a quality design approach with risk assessment followed by characterization such as FTIR, DSC, TGA, XRD, in vitro drug release, in vitro cytotoxicity study and in vivo pharmacokinetic studies. Results: The patient-centric quality target product profile (QTPP) was set. QTPP inspired critical quality attributes (CQAs) were searched out. The critical material attributes (CMAs) and critical process parameters (CPPs) influencing CQAs were distinguished. The seventeen formulations were fabricated employing Box Behnken Design, followed by optimization using numerical and graphical optimization techniques and the optimized microbeads were subjected to in vivo pharmacokinetic and in vitro cytotoxicity studies using HT 29 cell lines. The results revealed that 5-FU-loaded microbeads exhibited significantly more cytotoxic, and bioavailability was found to be nearly doubled as compared to pure drugs. Conclusion: 5-FU-loaded microbeads can be developed and optimized successfully by using quality by design approach and coating with eudragit S100, which can be targeted to the colon for the effective treatment of colorectal cancer.

Sensory optimization of an instant brown rice cereal containing tigernut and soybean

The aim of this study was to determine the optimum ingredient formulation for an instant rice-based cereal enriched with tigernut and soybean flours. An extreme vertices design involving three (3) components (brown rice flour, tigernut flour and soybean flour) was used. A slurry of the three (3) was dried on a single drum dryer at 120 °C and 5 rpm. Mixture regression modeling was used to assess the impact of each component on the functional quality and sensory attributes properties of the drum dried product. Graphical optimization of the formulation was performed by superimposing contour plots of individual sensory attributes examined. Predicted regression models showed that tigernut flour, followed closely by rice flour, had the largest effect on overall acceptance of the product. The optimum formulation for an acceptable drum dried product was determined to be rice flour – 46.6 %, tigernut flour – 39.1 % and soybean flour – 14.3 %. The product was stable during storage, as only marginal increment was recorded in the quality attributes assessed. This study provides an avenue for enhancing the utilization potential of both brown rice and tigernut.

Efficiency improvement of dual active bridge converter using simple graphical optimization method

SummaryAiming to the problems of high circulating current and low efficiency caused by the traditional strategy of dual active bridge (DAB) converter under light load, in this paper, simple graphical optimization method (GSO) is proposed to improve the efficiency of dual active bridge converter. Through the contour plot of transmission power and current stress, optimal efficiency point can be obtained by tangent of contour map under condition of constant power, and heavily calculation or complex iterations of existing conventional control strategies are avoided. Moreover, analysis of proposed graphical current stress optimization is addressed, and controller design of proposed method is given and described. Efficiency comparison between traditional modulation strategy and GSO is given to show the advantage of proposed mothed. An experimental prototype is built to verify the analysis.

Graphical optimization method for bidirectional corridor progression under the signal design mode of split phasing

Graphical optimization method for bidirectional corridor progression under the signal design mode of split phasing

RP-UFLC based Bioanalytical Method Development, Optimization, and Validation for the Estimation of Isradipine in Rabbit Serum

Introduction: The objective of this study is to provide a rapid, sensitive, consistent, and costeffective method for quantifying isradipine using ultra-fast liquid chromatography. Methods: Quality by Design principles will form the basis of this approach, grounded on response surface analysis. Shimadzu liquid chromatographic system equipped with a photodiode array detector and LC solution software was used to conduct the RP-UFLC method development and validation. An ODS C18 (250 x 4.6 mm; 5 μm) UFLC column was used to complete the analysis. The RSM methodology utilized a central composite design to perform the optimization studies. Results: The mobile phase ratio and flow rate were considered crucial method parameters, as well as the peak area, retention time, and USP plate were considered critical analytical attributes. The optimal conditions for chromatographic separation were followed using 80% acetonitrile and water (20% v/v) as mobile phase, a 1 mL/min flow rate, an injection volume of 20 μL, 40°C of column oven temperature, and maximum absorption at λmax 254 nm using graphical optimization technique. When examining concentrations between 5 and 150 ng/mL, linearity was observed with an R2 of 0.999. The method created was validated by employing stability testing per the recommendations provided by ICH Q2 (R1). The analysis of blood serum was modified so that it could be used to examine the pharmacokinetic parameters. Conclusion: As a result, high accuracy, precision, sensitivity, linearity, and robustness were established for predicting the amount of isradipine present in its freeze-dried nano-formulations.