In this topic, we applied the Fmincon function to the optimum question when choosing the structure of a 7-bar bearing steel bearing, divided into groups of the same size, including group 1 (1, 2 bars), group 2 (3, 4, and 5 bars), and group 3 (6, and 7 bars) with three fixed head points and two bearing points. Using the Matlab software code, we have identified the structures of each group of steel bars corresponding to the radius of 1.564 cm, 3.509 cm, and 4.724 cm, respectively. Through this, we can identify the 1, 2, and 3 bars that are resistant to traction; the 3, 5, 6, and 7 bars that are subject to compression; and the 4 bars alone that are not subject to the action of the force. The results show that using the optimal method, we choose the different sizes, thicknesses, and volumes of the pipe so that it best suits the technical requirements of the paper, to avoid waste of raw materials, affecting the economic cost.

Cordyceps has long been considered as a valuable medicinal herb known to possess numerous biological activities, including anti-microbial, anti-cancer, anti-metastasis and immunomodulatory effects. With its benefits, many studies on optimizing the cultivation and production of C. militaris have been carried out. In addition, extraction methods have also been improved to intense efficiency extract the medicinal substances contained in this rare fungi. In this study, the aim was to optimize the process of C. militaris extraction from fruiting bodies based on 17 experimental data using water extraction method. The factors that affects to the extraction productivity such as: extraction temperature, extraction time and water/fungi ratio were investigated within a certain range. The experiments were arranged according to the Box-Behnken design, and then the results was optimized by Design expert software (version 13). In the optimal condition, the maximum productivity can be up to 32.23% with the extraction temperature is at 98oC, the water/fungi ratio is 18:1 and the extraction time is 4 hours.

This study deals with the stiffness design of geometrically nonlinear structures using topology optimization. Bi-directional Evolutionary Structures Optimization (BESO) is employed to implement the design process. The geometrically nonlinear behavior of the structures are modeled using a total Lagrangian finite element formulation and the equilibrium is found using a Newton-Raphson iterative scheme. The topology optimization of linear and nonlinear modeling are implemented. The sensitivity of the objective function is found with the adjoint method and the optimization problem is solved using BESO’s update method. Objective function of complementary work is evaluated. A special technique called the continuation method is applied to solve the instability of nonlinear structure optimization. ANSYS APDL is also used to do FEA of optimal topology to verify the effectiveness of geometrically nonlinear modelling. The results show that differences in stiffness of structures optimized using linear and nonlinear modelling is generally small but it can be large in some cases, especially structure highly involving buckling behaviour.

High power losses are a great concern in operating electric distribution system. Reconfiguration is one of the most economic approaches for reducing power losses of the system. This study suggests a technique for dealing with the distribution system reconfiguration problem based on a water cycle algorithm for minimizing active power loss. The water cycle algorithm is a recently developed metaheuristic algorithm that inspired the process of water circulation for solving optimization problems. The effectiveness and performance of the water cycle algorithm were tested on the 33-node and 69-node systems. The water cycle algorithm was applied to determine the best configuration of the distribution system for active power loss minimization. The results yielded by the water cycle algorithm were compared with other optimization algorithms in the literature and the comparisons showed that the water cycle algorithm obtained good quality of solution for the problem. Therefore, the water cycle algorithm is the potential method for the distribution system reconfiguration problem.

Environmental issues such as the wastewater have influenced each aspect of our lives. For human and environmental health protection, it is necessary to remove excess zinc in industrial wastewaters before discharging them to environment. Modified diatomite displayed larger surface area and pore volumes in comparison with untreated natural diatomite, which favored heavy metals sorption behavior. In this study, the removal of Zn(II) ions from aqueous solution was studied using Fe/Mn modified diatomite sample at different adsorption parameters such as contact initial metal ions concentration, dosage of Fe/Mn-Diatomite and ionic strength Na2CO3 on ionic Zn2+ adsorption capacity of diatomite modified. The residual zinc concentration in the solution was determined using flame atomic absorption spectroscopy. The results showed that: the gravitational increase increases with increasing time and then becomes almost stable, with 120 minutes timeliness; absorption increases when Fe/Mn-Ditomite is increased, absorption reaches 89.48% at a dose of 1.5 g/l; additional different concentrations Na2CO3 ranged from 0 ppm to 80 ppm the results showed that performance treatment Zn2+ of correspond 94,85%. This study could lay an essential foundation to develop modified diatomite for heavy metal removal from wastewater.