Optimization of Grouting Material Mixture Ratio Based on Multi-Objective Optimization and Multi-Attribute Decision-Making

As a solid waste produced by coal combustion, fly ash will cause serious environmental pollution. However, it can be considered as a sustainable and renewable resource to replace partial cement in grouting materials. Fly ash grouting materials re-cement the broken rock mass and improve the mechanical properties of the original structure. It can reinforce the broken surrounding rock of mine roadway. The utilization of fly ash also reduces environmental pollution. Therefore, this paper establishes a new material mixture ratio optimization model to meet the requirement of material property through combining the methods of experimental design and numerical analysis. Based on the Box–Behnken design with 3 factors and 3 levels, a mathematical model is constructed to fit the nonlinear multiple regression functions between material properties and raw materials ratios. The influence of raw materials is analyzed on material properties (the material’s 7-day uniaxial compressive strength, initial setting time, and slurry viscosity). Then, 80 Pareto solutions are obtained through NASG-II algorithm which takes the regression functions as the objective functions for multi-objective optimization of the grouting material ratio. Finally, the best ratio solution of water-cement ratio—0.71, silica fume content—1.73%, and sodium silicate content—2.61% is obtained through the NNRP-TOPSIS method.

A New Hybrid Exponentially Weighted Moving Average control chart using Mixture Ratio Estimator of Mean

In this paper, we propose a Hybrid Exponentially Weighted Moving Average (HEWMA) control chart based on a mixture ratio estimator of mean using a single auxiliary variable and a single auxiliary attribute (Moeen et al., [1]). We call it as Z- HEWMA control chart. The proposed control chart performance is evaluated using outof- control-Average Run Length (ARL1). The control limits of the proposed chart is based on estimator, its mean square errors. A simulated example is used to compare the proposed Z-HEWMA, traditional/simple EWMA chart and CUSUM control chart. From this study the fact is revealed that Z-HEWMA control chart shows more efficient results as compared to traditional/simple EWMA and CUSUM control charts. The Z-HEWMA chart can be used for efficient monitoring of the production process in manufacturing industries where auxiliary information about a numerical variable and an attribute is available.

Study of Investment in the Organic Fertilizer Industry to Improve Community Economists

Based on the results of observations of organic waste in the village of Jogotirto Berbah, Sleman, it is known that the amount of household organic waste and cow dung from 2015 to 2020 continues to increase by ± 12% per year. In Jogotirto, the average person produces 0.36 kg of organic waste per day and 15 kg of dry cow dung per day. In 2020 the amount of household organic waste is 8,477 kg per day, while for cow dung is 16,787.75 kg per day. Analysis of the study of the establishment of the organic fertilizer industry is carried out by processing household organic waste and solid cow dung by fermentation. This fermentation process is carried out anaerobically for 21 days. The organic fertilizer processing process is carried out by mixing cow dung and household waste with varying ratios. From the results of research on making organic fertilizer, it is known that a mixture of cow dung and household waste with a mixture ratio of 2: 1 contains nitrogen compounds as much as 1.04%, organic C 17.6%, phosphorus 1.7% and potassium as much as 7.02%. Based on the analysis of investment feasibility using the Net Present Value method, the fertilizer industry can generate a profit of 200.18% for 5 years. Analysts using the ROR method can provide a profit of 31.7% per year and the analysis using the pay back method is known that the period of capital will return after 3.85 years. Based on the sensitivity test of the fertilizer industry, it is still said to be safe for changes in influencing parameters, namely the sensitivity rate of 20%. This study of the establishment of the organic fertilizer industry aims to provide advice to the government in the context of improving the community's economy.

Non-synaptic interactions between olfactory receptor neurons, a possible key feature of odor processing in flies

When flies explore their environment, they encounter odors in complex, highly intermittent plumes. To navigate a plume and, for example, find food, they must solve several challenges, including reliably identifying mixtures of odorants and their intensities, and discriminating odorant mixtures emanating from a single source from odorants emitted from separate sources and just mixing in the air. Lateral inhibition in the antennal lobe is commonly understood to help solving these challenges. With a computational model of the Drosophila olfactory system, we analyze the utility of an alternative mechanism for solving them: Non-synaptic (“ephaptic”) interactions (NSIs) between olfactory receptor neurons that are stereotypically co-housed in the same sensilla. We find that NSIs improve mixture ratio detection and plume structure sensing and do so more efficiently than the traditionally considered mechanism of lateral inhibition in the antennal lobe. The best performance is achieved when both mechanisms work in synergy. However, we also found that NSIs decrease the dynamic range of co-housed ORNs, especially when they have similar sensitivity to an odorant. These results shed light, from a functional perspective, on the role of NSIs, which are normally avoided between neurons, for instance by myelination.

Biomethane Production from Anaerobic Co-Digestion of Selected Organic Fraction of Municipal Solid Waste (OFMSW) with Sewage Sludge: Effect of the Inoculum to Substrate Ratio (ISR) and Mixture Composition on Process Performances

The aim of this study was to evaluate the effect of the inoculum to substrate ratio (ISR) and the mixture ratio between organic fraction of municipal solid waste (OFMSW) and sewage sludge (SS) on the methane production potential achievable from anaerobic co-digestion (AcoD). Biochemical Methane Potential (BMP) assays at mesophilic temperature were used to determine the best AcoD configuration for maximizing methane yield and production rate, as well as to address possible synergistic effects. The maximum methane yield was observed at ISR of 1 and 60% OFMSW :40% SS as co-digestion mixture, whereas the highest methane production rate was achieved at ISR of 2 with the same mixture ratio (207 mL/gVS/d). Synergistic effects were highlighted in the mixtures having OFMSW below 60%, determining an increase of approximately 40% in methane production than the OFMSW and SS digestion as a sole substrate. The experimental data demonstrated that co-digestion of OFMSW and SS resulted in an increase in the productivity of methane than anaerobic digestion using the sole substrates, producing higher yields or production rates while depending on the ISR and the mixture ratio.

Preparation and Characterization of NiCr/NiCr-Al2O3/Al2O3 Multilayer Gradient Coatings by Gas Detonation Spraying

This paper investigates the influence of the technological parameters of detonation spraying on the phase composition of NiCr- and Al2O3-based coatings. It was determined that the phase composition of Al2O3 coatings during detonation spraying strongly depends on the barrel filling volume with the gas mixture. The acetylene–oxygen mixture, which is the most frequently used fuel in the detonation spraying of powder materials, was used as a fuel gas. To obtain a ceramic layer based on Al2O3, spraying was performed at an acetylene–oxygen O2/C2H2 mixture ratio of 1.856; the volume of filling of the detonation gun barrel with an explosive gas mixture was 63%. To obtain a NiCr-based metallic layer, spraying was performed at the O2/C2H2 ratio of 1.063; the volume of filling of the detonation gun barrel with an explosive gas mixture was 54%. Based on a study of the effect of the detonation spraying mode on the phase composition of NiCr and Al2O3 coatings, NiCr/NiCr-Al2O3/Al2O3-based multilayer coatings were obtained. Mixtures of NiCr/Al2O3 powders with different component ratios were used to obtain multilayer gradient coatings. The structural-phase composition, mechanical and tribological properties of multilayer gradient metal–ceramic coatings in which the content of the ceramic phase changes smoothly along the depth were experimentally investigated. Three-, five- and six-layer gradient coatings were obtained by alternating metallic (NiCr) and ceramic (Al2O3) layers. The phase composition of all coatings was found to correspond to the removal of information from a depth of 20–30 μm. It was determined that the five-layer gradient coating, consisting of the lower metal layer (NiCr), the upper ceramic layer (Al2O3) and the transition layer of the mechanical mixture of metal and ceramics, is characterized by significantly higher hardness (15.9 GPa), wear resistance and adhesion strength.

Optimizing Yield and Quality of Silage and Hay for Pea–Barley Mixtures Ratio under Irrigated Arid Environments

The changing climate, water scarcity, reduction in the land area under forage crops, expanding ruminant population, burgeoning demands for milk and meat production and food security concerns all insist on a necessary increase in forage production and quality. Cereal–legume mixed intercropping offers a biologically superior option to boost herbage yield and quality of preserved fodder (hay and silage), provided that rationalization of the component crop’s proportional ratio is performed. Therefore, the current study was conducted to determine the forage yield and quality of barley (Hordeum vulgare L.) and pea (Pisum sativum L.) mixtures at the ratios 100:0, 75:25, 50:50, 25:75 and 0:100. The experiment was laid out in the regular arrangement of a randomized complete block design with three replicates. The results exhibited that forage quality was significantly affected by the mixture ratio. There was a significant improvement in protein, fiber rate and digestibility from the mixture. The ratios of barley and pea with 50:50 and 25:75 produced the maximum productivity and the best quality of forage. Regarding forage preservation, silage recorded higher contents of crude protein, ash and lower fiber contents than hay. Among seed mixtures, 0:100 ratio of barley–pea yielded the highest quality of silage with the maximum crude protein, ash and digestibility with lowest fiber contents.

Effects of Co-Solvents on Loading and Release Properties of Self-Assembled Di-Peptide Building Blocks, towards Drug Delivery Applications

Background: Due to their solid-like porous structure, molecular organogel and microcrystal structures have the capabilities of loading drug molecules, encapsulation, and extended release, all considered as essential properties in drug delivery applications. Phases of these structures, however, depend on the solvent used during the gelation process. Objective: Understanding the phase transition between organogel and microcrystal structures through adjusting the mixture ratio of different co-solvents. Method: Short peptide Diphenylalanine as the gelation building block was used due to its amino acid sequences that can be exactly selected at its molecular levels. Ethanol as a polar solvent was used in combination with four other co-solvents with different polarity levels, namely Xylene, Toluene, Acetone, and Dimethyl Sulfoxide. The morphology of molecular structures of each co-solvent combination at each ratio level was examined as well as the loading and release properties for a non-polar Flufenamic Acid drug. Results: The resultant structure wasaffected by the polarity of the co-solvents; in particular, in the sample containing 25 μg/ml of the drug, 94% of the drug amount was loaded inside the organogel. By increasing the drug concentration to 50, 75, and 100 μg/ml, the loading capability decreased to 76%, 47%, and 33%, respectively. Conclusion: Molecular organogels have excellent capabilities of loading drug molecules, while microcrystal structures have higher release capacity. The findings of this study reveal how to best design a gelation method to obtain maximum loading or release properties for a particular peptide-based drug delivery application.

Chemical Kinetic Study on Dual-Fuel Combustion: The Ignition Properties of n-Dodecane/Methane Mixture

The natural gas (NG)/diesel dual-fuel engine has attracted extensive attention in recent years, and the influence of ignition delay on the engine is very important. Therefore, the research on the ignition delay of NG/diesel dual fuel is of great significance. In this work, a simplified n-dodecane mechanism was used to study the effect of methane mixture ratio on the n-dodecane ignition process. The results showed that the ignition delay time increased with the increase of methane content by changing the mixing ratio of methane and n-dodecane. However, the effect of methane on the ignition delay time gradually decreases when the content of the n-dodecane mixing ratio is greater than 50%. It was also found that with the increase of n-dodecane content, the reduction degree of the ignition delay time of the whole reaction system decreased and the negative temperature coefficient (NTC) behavior increased. Moreover, when the initial pressure increased from 20 bar to 60 bar, the thermal effect of methane also increases from 7.03% to 9.55%. The relationship between ignition characteristics of methane-n-dodecane and temperature was studied by changing the initial temperature. Furthermore, the evolution of species in the ignition process of the whole reaction system was analyzed, and the decomposition of n-dodecane first occurs in the reaction n-C12H26 + O2 = R + HO2 to form R and free radicals; however, the reaction CH4 + OH = CH3 + H2O dominates with the increase of the methane mixing ratio and inhibits the ignition process. Through the analysis of reaction paths, sensitivity, and rates of production and consumption of methane/n-dodecane, it was explained how n-dodecane accelerates methane ignition through the rapidly formed free radicals.