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The rising complexity of business changes has increasingly highlighted the requirements to provide a comprehensive and empirical framework for the supply chain agility (SCA). A review of extant studies shows that the results are complicated and ambiguous. Moreover, this study is a meta-analytical review of previous empirical studies to identify SCA antecedents and effects of SCA on firm performance.

According to the protocol, 64 studies were chosen as the sample to survey the relationships between five clusters of SC allopoietic properties (SCAPs) (SC connectivity, symbiotic relationship (SR), cognitive openness (CO), homeostasis and collaboration) and SCA, as well as its effects on firm performance.

Among antecedents, horizontal collaboration’s effect on SCA is the strongest, and the relationship between SR-SCA and CO-SCA is less than moderate. SCA affects firm performance and its dimensions, with a stronger effect on financial performance (FP). Furthermore, the SCA study in the framework of allopoietic systems is a good starting point for future research.

Managers are advised to constantly review repetitive interactions between the company and its environment and to learn about interactions between SC and the environment. Learning from these interactions and disseminating their explicit knowledge among company members lead to a quick response to the environmental instability.

As the first meta-analysis on SCA antecedents and its effects on firm performance, this study contributes to the SCA literature and provides research directions for the future.

This research presents a design method for designing greenhouse structures based on topology optimization. Moreover, the structural design of a gothic greenhouse is proposed in which its structural strength has been improved by using this proposed method. In this method, the design of the structure is done mathematically; therefore, in the design process, more attention can be focused on the constraint space and boundary conditions. It was also shown how the static reliability and fatigue coefficients will change as a result of the design of the greenhouse structure with this method. Another purpose of this study is to find the weakest part of the greenhouse structure against lateral winds and other general loads on the greenhouse structure.

In the proposed method, the outer surface and the allowable volume as a constraint domain were considered. The desired loads can be located on the constraint domain. The topology optimization was used to minimize the mass and structural compliance as the objective function. The obtained volume was modified for simplifying the construction. The changes in the shape of the greenhouse structure were investigated by choosing three different penalty numbers for the topology optimization algorithm. The final design of the proposed structure was performed based on the total simultaneous critical loads on the structure. The results of the proposed method were compared in the order of different volume fractions. This showed that the volume fraction approach can significantly reduce the weight of the structure while maintaining its strength and stability.

Topology optimization results showed different strut and chords composition because of the changes in maximum mass limit and volume fraction. The results showed that the fatigue was more hazardous, and it decreased the strength of structure nearly three times more than a static analysis. Further, it was noticed that how the penalty numbers can affect topology optimization results. An optimal design based on topology optimization results was presented to improve the proposed greenhouse design against destruction and demolition. Furthermore, this study shows the most sensitive part of the greenhouse against the standard loads of wind, snow, and crop.

The obtained designs were compared with a conventional arch greenhouse, and then the structural performances were shown based on standard loads. The results showed that in designing the proposed structure, the optimized changes increased the structure strength against the standard loads compared to a simple arch greenhouse. Moreover, the stress safety factor and fatigue safety factor because of different designs of this structure were also compared with each other.