Optical Satellite Multiobjective Genetic Algorithms for Investigation of MH370 Debris

At present, there is no precise method that can inform where the lost flight MH370 is. This chapter proposes a new approach to search for the missing flight MH370. To this end, multiobjective genetic algorithms are implemented. In this regard, a genetic algorithm is taken into consideration to optimize the MH370 debris that is notably based on the geometrical shapes and spectral signatures. Currently, there may be three limitations to optical remote sensing technique: (1) strength constraints of the spacecraft permit about two hours of scanning consistently within the day, (2) cloud cover prevents unique observations, and (3) moderate information from close to the ocean surface is sensed through the scanner. Needless to say that the objects that are spotted by different satellite data do not scientifically belong to the MH370 debris and could be just man-made without accurate identifications.

АЛГОРИТМ НАЗНАЧЕНИЯ РЕЖИМОВ ТЕРМОИМПУЛЬСНОЙ ОБРАБОТКИ С УЧЕТОМ ПРОЧНОСТНЫХ ОГРАНИЧЕНИЙ

The analysis of the applicability of the finish thermal energy and thermal pulse treatment by detonable gas mixtures to various parts determine the need to take into consideration the strength constraints, which in turn is the subject matter of investigation when treatment settings are determined. The goal of the article is to develop an algorithm of settings assigning for thermal pulse finishing taking into account strength constraints of a part. In this regard, as the research tasks, existing methods for designating treatment regimes, including clarifying approaches, have been analyzed. The most probable factors affecting the possible destruction of parts under the action of thermal pulse loads are considered and the need for their comprehensive accounting is determined. The following results are obtained. Evaluation of the distortion possibility of the part shape in places with a minimal wall thickness should be performed by follow condition: plastic deformations in metal must not be reached in the dangerous zones during processing. When the maximum time of thermal pulse action is determined, provided that the residual deformations in the workpiece surface layer are present, it is necessary to amount the anisotropy of the linear thermal expansion coefficient and to apply the Johnson-Cook model, which calculates the dynamic yield strength of the material. Subject to the plasticity resource is exhausted, the possibility of the material destruction must be evaluated according to the criterion of the plasticity resource using as the ratio of the accumulated deformation degree to the maximum allowable state under a certain scheme. For parts with structural heterogeneity, it is suggested to define the possibility of developing cracks from internal pore zones, by determining the values of the stress intensity factor or the J-integral and comparing them with critical values. The following conclusions are formulated. An algorithm for assigning settings for thermal pulse finishing has been developed. The proposed approach ensures to determine agreed settings of the necessary energy of equipment to treat parts with specified qualimetry parameters and the sufficient one from the standpoint of strength requirements. Stability of processing quality should be provided by systems for filling the mixture, burning and releasing the products of combustion of automated thermal pulse equipment.

OPTIMUM BUCKLING DESIGN OF CYLINDRICAL STIFFENER SHELL UNDER EXTERNAL HYDROSTATIC PRESSURE

This paper present an investigation of the collapse load in cylinder shell under uniformexternal hydrostatic pressure with optimum design using finite element method viaANSYS software. Twenty cases are studied inclusive stiffeners in longitudinal and ringstiffeners. Buckling mode shape is evaluated. This paper studied the optimum designgenerated by ANSYS for thick cylinder with external hydrostatic pressure. The primarygoal of this paper was to identify the improvement in the design of cylindrical shell underhydrostatic pressure with and without Stiffeners (longitudinal and ring) with incorporativetechnique of an optimization into ANSYS software. The design elements in this researchwas: critical load, design variable (thickness of shell (TH), stiffener’s width (B) andstiffener’s height (HF). The results obtained illustrated that the objective is minimizedusing technique of numerical optimization in ANSYS with optimum shell thickness andstiffener’s sizes. In all cases the design variables (thickness of shell) was thicker than themonocoque due to a shell’s thicker is essential to achieve the strength constraints. It can beconcluded that cases (17,18,19, and 20) have more than 90% of un-stiffened critical load.The ring stiffeners causes increasing buckling load than un-stiffened and longitudinalstiffened cylinder.

Buckling Analysis of Belly Shaped Composite Column

The study of Non prismatic column is designed to minimize the volume of material in the column by changing its shape, the column is subject to both buckling and strength constraints under axial compression load. The belly column is designed as Encased Composite column to improve the strength and ductility of column. The effective use of material through optimal shape of the column. Five models have been created in ANSYS WORKBENCH and all the columns having the same volume of materials, fixed end conditions and length of column. The behaviour of non-prismatic column is always based on tapering ratio and the slenderness ratio of the column. As the taper ratio increases, the elastic buckling load increases and stress decreases in the mean while the maximum stress occurs in the prismatic column compared with the non-prismatic column. As a result of this analysis Equivalent stress, Equivalent elastic strain, Total Deformation and Buckling load Deformation was observed and hence Stress-Strain graphs, Load -Deformation graphs and Mode-Load multiplier graph had been plotted.

Development of a new method for design of stiffened composite pressure vessels using lattice structures

A new method to design composite pressure vessels under strain and strength constraints using lattice structures is described. A graphical analysis is presented to find the optimum geometrical parameters of the rib for given fiber orientations. Minimum pressure vessel mass is determined from active execution of two constraints. Composite lattice structures are suggested as a new way of strain suppression among the commonly used methods such as (1) addition of extra plies, (2) use of composite material with a higher stiffness and (3) replacement of the circumferential layer with a second helical layer made of different materials. The experimental and analytical results of application of the method indicate that the vessel covered with composite lattice structures presented considerable weight savings with respect to traditional stiffened vessels.