Introduction: Fungi broadly exist in the environment. Growing interest for natural and safe additives as well as concerns about synthetic fungicide have led to development of various fungicides. This study aimed to examine the effect of walnut Thin Shell ethanolic extract on the growth of Penicillium species. Methods: Antifungal effects were assessed at four different concentrations ranging from 5 to 350 mg/ml. The extract dilutions were exposed to the desired fungi using the broth dilution method, and minimum inhibitory concentrations (MIC) of fungi were determined and compared with the effects of nystatin and fluconazole. Results: The MIC for Penicillium italicum was 15 mg/ml for both walnut Thin Shell and fluconazole whereas it was 30 mg/ml for nystatin. Moreover, the minimum fungicidal concentration (MFC) for walnut Thin Shell, fluconazole and nystatin were 250, 30 and 60 mg/ml, respectively. The MIC for Penicillium expansum was 30 mg/ml for both walnut Thin Shell and fluconazole while it was 40 mg/ml for nystatin. The results also revealed that the MFC for these inhibitors was 300, 40 and 70 mg/ml, respectively. Furthermore, the MIC for Penicillium digitatum for both the Shell walnut extract and nystatin was 40 mg/ml while it was 20 mg/ml for fluconazole. The MFC for walnut Thin Shell, fluconazole and nystatin were 325, 100 and 70 mg/ml, respectively. Conclusion: Thin walnut Shell extract has significant antifungal effects on Penicillium species and could be used as a natural antifungal. More research is required to assess the use of the extract for treatment of fungal infections.

One of the common failure modes of Thin cylindrical Shell subjected external pressure is buckling. The buckling pressure of these Shell structures are dominantly affected by the geometrical imperfections present in the cylindrical Shell which are very difficult to alleviate during manufacturing process. In this work, only three types of geometrical imperfection patterns are considered namely (a) eigen affine mode imperfection pattern, (b) inward half lobe axisymmetric imperfection pattern extended throughout the height of the cylindrical Shell and (c) local geometrical imperfection patterns such as inward dimple with varying wave lengths located at the mid-height of the cylindrical Shell. ANSYS FE non-linear buckling analysis including both material and geometrical non-linearities is used to determine the critical buckling pressure. From the analysis it is found that when the maximum amplitude of imperfections is 1t, the eigen affine imperfection pattern gives out the lowest critical buckling pressure when compared to the other imperfection patterns considered When the amplitude of imperfections is above 1t, the inner half lobe axisymmetric imperfection pattern gives out the lowest critical buckling pressure when compared to the other imperfection patterns considered.

This study presents the optimized shape and thickness of Thin continuous concrete Shell structures, minimizing their weight, deflection, and elastic energy change while meeting the performance requirements and minimizing material usage. Unlike previous studies that focused on single-objective optimization, this research focuses on multi-objective optimization (MOO) by considering three objective functions. This combination of objective functions has not been reflected in previous research, distinguishing this study. The computational design workflow incorporates a parametric model, multiple components for measuring objective functions in the grasshopper of Rhino, and a metaheuristic algorithm, the non-dominated sorting multi-objective genetic algorithm (NSGA-II), as the search tool, which was coded in Python. This workflow allows us to perform form-finding and optimization simultaneously. To demonstrate the effectiveness of this metaheuristic algorithm in structural optimization, we applied it in a case study of a well-known Shell designed using the physical prototyping hanging model technique. Interpretations of samples of optimized results indicate that although solution 1 weighs nearly the same as solution 2, it has less deflection and strain energy. Solution 3, with a three-fold mass, has significantly less deflection and strain energy than solution 1 and solution 2, with deflection reductions of over 50 and 17%, respectively. Solutions 3 and 4 show better deflection and strain energy performance. Furthermore, a comparison of the MOO results with the Isler Shell revealed that this method found a solution with less weight and deflection while being stiffer, confirming its practicality. The study found that MOO is a reliable method for form-finding and optimization, generating accurate and reasonable results.

It is well known that it is very difficult to manufacture perfect Thin cylindrical Shell. Initial geometrical imperfections existing in the Shell structure is one of the main determining factor for load bearing capacity of Thin cylindrical Shell under uniform lateral pressure. As these imperfections are random, the strength of same size cylindrical Shell will also random and a statistical method can be preferred to find the allowable load of these Shell structures and therefore a In this work the cylindrical Shell of size R/t = 228, L/R = 2 and t=1mm is taken for study. The random geometrical imperfections are modeled by linearly adding the first 10 eigen mode shapes using 2k full factorial design matrix of DoE. By adopting this method 1024 FE random imperfect cylindrical Shell models are generated with tolerance limit of ± 1 mm. Nonlinear static FE analysis of ANSYS is used to find the buckling strength of these 1024 models. FE results of 1024 models are used to predict the reliability based on MVFOSM method.

This paper presents the study on influence external pressures on vibration of functionally graded materials Thin-walled cylindrical Shell supported. The functionally graded materials (FGMs) properties are graded in the thickness direction of the Shell. FGMs are advanced composite materials, consisting of different types of materials, in which the properties shift continuously from one material on the one side to another material on the other side with a specific gradient. The FGM cylindrical Shell supported equations with external pressure are established based on classical Shell theory with beam functions as axial modal function. The governing equations of motion were employed, using energy functional and by applying the Ritz method. The boundary conditions represented by end conditions of the FGM structure which are sliding-sliding, clamped-free and clamped-simply supported being considered. This problem was solved with computer programming using MAPLE package. Comparison results are carried out to verify the validity with published papers. The influence of the external pressures, loop support and effect of the different boundary conditions on natural frequencies of FGM Thin-walled cylindrical Shell are studied.

In this work the equations of motion of a Solid State Wave Gyroscope (SWG) with rotary Thin cylindrical Shell resonator is analyzed using the Shell & plates elasticity theory. The gyroscope conversion factor found in this analytical study corresponds with the experimental results obtained and listed in the References. The function of the SWG to measure the angular velocity or the rotating angle depends on the type of resonator’s excitation. This paper analyzes two types of excitations, a positional and a parametric excitation. The former has a rate gyroscope whereas the latter has a rate integrating gyroscope. The equations of motion are solved using Bobnov-Galerkin method, where the forces produced from excitation electrodes are assumed to be the external non-conservative forces. Finally, the relationship between the input and output of the gyroscope are derived to demonstrate that the type of the excitation, determines the type of gyroscope.

In this paper, an elastic Shell model is presented for postbuckling prediction of a long Thinwalled cylindrical Shell under axial compression. The Ritz method is applied to solve the governing equilibrium equation of a cylindrical Shell model based on the von-Karman type nonlinear differential equations. The postbuckling equilibrium path is obtained using the energy method for a long Thin-walled cylindrical Shell. Furthermore, the postbuckling relationship between the axial stress and end-shortening is investigated with different geometric parameters. Also, this theory is used for postbuckling analysis of a single-walled carbon nanotube without considering the small scale effects. Numerical results reveal that the single-walled carbon nanotube under axial compression has an unstable postbuckling behavior.