The use of a fuzzy multi-objective linear programming for solving a multi-objective single-machine scheduling problem

This paper develops a fuzzy multi-objective linear programming (FMOLP) model for solving a multi-objective single-machine scheduling problem. The proposed model attempts to minimize the total weighted tardiness and makespan simultaneously. In this problem, a proposed FMOLP method is applied with respect to the overall acceptable degree of the decision maker (DM) satisfaction. A number of numerical examples are solved to show the effectiveness of the proposed approach. The related results are compared with the Wang and Liang's approach. These computational results show that the proposed FMOLP model achieves lower objective functions and higher satisfaction degrees.     

Evaluation of antibacterial property of hydroxyapatite and zirconium oxide‐modificated magnetic nanoparticles against Staphylococcus aureus and Escherichia coli

In the first section of this research, superparamagnetic nanoparticles (NPs) (Fe₃ O₄) modified with hydroxyapatite (HAP) and zirconium oxide (ZrO₂) and thereby Fe₃ O₄ /HAP and Fe₃ O₄ /ZrO₂ NPs were synthesised through co‐precipitation method. Then Fe₃ O₄ /HAP and Fe₃ O₄ /ZrO₂ NPs characterised with various techniques such as X‐ray photoelectron spectroscopy, X‐ray diffraction, scanning electron microscopy, energy dispersive X‐ray analysis, Brunauer–Emmett–Teller, Fourier transform infrared, and vibrating sample magnetometer. Observed results confirmed the successful synthesis of desired NPs. In the second section, the antibacterial activity of synthesised magnetic NPs (MNPs) was investigated. This investigation performed with multiple microbial cultivations on the two bacteria; Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Obtained results proved that although both MNPs have good antibacterial properties, however, Fe₃ O₄ /HAP NP has greater antibacterial performance than the other. Based on minimum inhibitory concentration and minimum bactericidal concentration evaluations, S. aureus bacteria are more sensitive to both NPs. These nanocomposites combine the advantages of MNP and antibacterial effects, with distinctive merits including easy preparation, high inactivation capacity, and easy isolation from sample solutions by the application of an external magnetic field.Inspec keywords: nanocomposites, X‐ray chemical analysis, microorganisms, magnetic particles, scanning electron microscopy, precipitation (physical chemistry), nanomagnetics, X‐ray diffraction, X‐ray photoelectron spectra, nanoparticles, superparamagnetism, iron compounds, antibacterial activity, biomedical materials, nanomedicine, calcium compounds, nanofabrication, Fourier transform infrared spectra, magnetometers, zirconium compoundsOther keywords: antibacterial effects, antibacterial property, superparamagnetic nanoparticles, X‐ray photoelectron spectroscopy, X‐ray diffraction, X‐ray analysis, antibacterial activity, bactericidal concentration, S. aureus bacteria, Staphylococcus aureus, Escherichia coli, hydroxyapatite, coprecipitation method, scanning electron microscopy, energy dispersive X‐ray analysis, Brunauer‐Emmett‐Teller method, Fourier transform infrared spectroscopy, vibrating sample magnetometer, microbial cultivations, nanocomposites     

Sensitivity Analysis of Soil Hydraulic Properties on Subsurface Water Flow in Furrows

Knowledge of the sensitivity of various soil hydraulic properties is beneficial for model development and application purposes. It can lead to better estimated values, better understanding, and thus reduced uncertainty. In the present study, an extensive sensitivity analysis was performed to investigate the effects that various soil hydraulic properties have on subsurface water flow below furrows during two successive irrigation events to see which irrigation event was more sensitive and to analyze the effect of spatial variations in the initial soil water contents within the soil profile. Testing the sensitivity of the various soil hydraulic parameters in the van Genuchten-Mualem expression was carried out using the HYDRUS-2D model for two irrigation events 10?days apart. Results showed that the first irrigation event was clearly more sensitive than the second one. The latter event was mainly associated with the nonuniformity of the initial soil water contents within the soil profile. Pressure heads in the soil profile were more sensitive than cumulative outlet fluxes and soil water contents. Sensitivity analysis results for pressure heads, cumulative fluxes, and water contents indicated that in every case the most sensitive parameter was the hydraulic property shape factor (n) followed by the saturated water content (θs), the saturated hydraulic conductivity (Ks), the residual water content (θr), and the shape factor in the soil water retention curve (α), with the pore-connectivity parameter (l) the least sensitive parameter during both irrigation events. Pressure head sensitivity analysis for all parameters studied showed that the least sensitivity was linked with the wetting front as it gradually moved deeper with time, and the highest sensitivity was observed in those regions where the initial soil water contents were lower. Similarly, for water contents, higher sensitivity occurred in the drier regions during the first irrigation event and near the moisture front in the second irrigation event. Both pressure heads and water contents showed some sensitivity near the soil surface during both irrigation events, suggesting the importance of evaporation from the soil surface.     

Antenna Patch Design Using a Photonic Crystal Substrate at a Frequency of 1.6 THz

Wireless Personal Communications - In this paper, the design of a macro strip patch antenna with a photonic crystal structure has been studied. The purpose of this study is to create a photonic...     

From rose petal to bone scaffolds: Using nature to fabricate osteon-like scaffolds for bone tissue engineering applications

In this study, rose petal was used to fabricate osteon-like scaffolds for bone tissue engineering applications. Rose petal was coupled with nanocrystalline forsterite colloid to mimic the lamellar structure of porous osteons. The microstructures on the surface of the petals were utilized as template for pores and lacuna spaces which are suitable for cell attachment. On the other hand, rolling the petals allowed us to form the osteon structure with haversian canal and lacuna spaces on the body of the samples. After trying different temperatures, the results showed that samples annealed at 1100 °C closely mimicked the lacuna spaces, haversian canal, and lamellar structures of osteons. These scaffolds had the pore diameter in the range of about 13–20 μm and presented good bioactivity and biocompatibility. It was found that red rose petal is a good candidate to be used as a template for designing scaffolds for bone tissue engineering applications.     

Fracture of hardened cement paste and concrete

The paper reviews literature on work in the field of fracture mechanics of hardened cement paste, cement mortar and concrete from the very beginning in 1929. Application of Griffith's theory for fracture of brittle solids to heterogeneous composite cement and concrete materials is discussed. Experimental data on fracture parameters from previous work by others is tabulated and compared. Macroscopic fracture mechanism and crack patterns of cement paste and concrete in tension and compression, as well as microscopic aspects of fracture mechanism in cement paste, are discussed.     

Thermal performance of adobe structures with domed roofs and moist internal surfaces

The inside air and the mean radiant temperatures of two buildings, one built of brick having a flat roof and the other built of lightweight adobe and having a domed roof, were estimated through a thermal network analysis. The analysis was repeated for both buildings when their ceilings and inside wall surfaces were kept moist and evaporatively cooled. A design day for a hot, arid region was considered for the analysis. It is shown that the temperature of the moist surfaces is reduced appreciably and the floor and the air temperatures are also reduced by their heat transfer to the moist surfaces. When natural ventilation rate is high, the room air does not become uncomfortably humid.With low mean radiant temperature in the moist buildings, thermal comfort can be maintained for the occupants. The total area and the duration when the surfaces are kept moist, along with the natural ventilation rate, can be controlled by the occupants to provide thermal comfort when it is otherwise uncomfortable. The use of a domed roof with a hole in its crown can ensure high ventilation rates at low wind velocities and in buildings which cannot otherwise be sufficiently vented.