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The prediction of accurate failure strength and a composite laminate failure load is of paramount importance for reliable design. The progressive failure analysis helps to predict the ultimate failure strength of the laminate, which is more than the first ply failure (FPF) strength. The presence of a hole in the laminate plate results in stress concentration, which affects the failure strength. The purpose of the current work is to analyze the stress variation and progressive failure of a symmetric laminated plate containing elliptical cutouts under in-plane tensile loading. The effect of various parameters on FPF and last ply failure (LPF) strength is studied.

The ply-by-ply stresses around elliptical cutouts are obtained analytically using Muskhelishvili's complex variable formulation. To predict the progressive failure, Tsai–Hill (T-H) and Tsai–Wu (T-W) failure criteria are used, and depending on the mode of failure, lamina modulus is degraded.

The study has revealed that fiber orientation and stacking sequence for given loading have the most significant effect on the laminate's failure strength.

Complex variable method and conformal mapping are simple and proficient for studying failure analysis of a laminated plate with elliptical cutout.

Farmers in developing countries are used to recycling and purchasing seeds of old and low-yielding varieties, leading to low seed and varietal replacement rates. Seed companies in Nepal have started to conduct traders' meetings (TMs) to promote new rice varieties. This paper aims to assess the effectiveness of this approach in promoting new rice varieties.

The authors assess the effectiveness of TMs by surveying 238 agrodealers from 7 districts of Nepal. The authors used the binary logit model to study the determinants of participation in TM and an instrumental variable approach to estimate the impact of TMs on sales of the promoted rice varieties.

Results indicate that the TM significantly influences traders' knowledge and increases the probability of selling new rice varieties promoted. However, TMs did not significantly increase the overall sales of promoted rice varieties.

The study is based on cross-section data; thus, unobserved fixed effects could not be accounted for. The study finds only one relevant and valid instrumental variable and therefore could not conduct any exogeneity test.

Seed companies in Nepal started to conduct TMs to promote new rice varieties since 2019. However, to the best of the authors’ knowledge, the usefulness of TMs and the impact of these events in changing traders' attitudes toward domestic rice seed varieties or in business performance (annual sales of the promoted varieties) have not been assessed. Therefore, the study findings will help to promote the market-driven seed system and increase the seed replacement rate.