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In this paper the design and manufacturing of Iosipesque shear test fixture modification evaluated. This shear test Fixture by applying the shear load in layered of composites specimens can predict the mechanical properties of composite materials in mode II of fracture.In this paper, first, a common traditional Iosipesque shear test fixture according to the standard was manufactured. Then, by applying shear load on polymer-based composites (carbon-epoxy) and wood (a natural composite) specimens, bugs of the traditional fixture were found.Finally by 6 fundamental Modification of the fixture structure, the new design was proposed. It was also found that by applying these reforms, both of concentrating the shear force (in the shear zone) and test accuracy has been increased. Accordingly, after the construction and testing of new fixture on wood and polymer based composite specimens and by applying the standard deviation’s equations, the standard deviation of the modified fixture for wood and polymer based composite has ben reduced 82.7% and 48% respectively, that suggesting the accuracy of the fixture. In addition, fluctuations of the fixtures diagram of the new design also significantly reduced.

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The aim of study was estimated and compared intra-laboratory quantification deviation (SIR) or measurement uncertainty (MU) as a performance Charateristics  in verification of  the implementation  step of quantitative test methods in food microbiology laboratories. The aerobic mesophilic colony counts of   microorganisms (ACC) and Enterobacteriaceae colony count (ECC), as two important and common tests in the microbial evaluation of all type of food was selected and interlaboratoary standard deviation estimation of selected food items: minced meat, hamburger, soy powder, pasteurized liquid eggs, pasteurized and UHT milk, ice cream, Fruit  juice, flour, cake and spice (PEPER) were calculated based on ISO-19036 standard method (2019). In this comparison, technical, matrix, distribution, confirmation and combined  Uncertinity were calculated and reported. Calculation of the technical uncertainty of the ECC test in (pasteurized and ultra-heated milk, ice cream, fruit juice and pasteurized liquid eggs) by created the artificial contamination on three levels with the target organism (Shigella felxseneri) and in other food items it was natural contamination, in the ACC test was only natural contamination was calculated. The technical uncertainty results of the ECC test ranged from 0.487 to 0.07 and in the ACC test, from 0.390 to 0.105 log10 cfu/g. The highest values of technical and matrix uncertainty were observed in meat, cake, hamburger and cheese samples, which showed the heterogeneous foods (solid and semi-solid) and the lowest values were observed in liquid (homogeneous) samples. Evaluation of variability and followed the uncertainty is proposed as a way to standardize the expression of variability associated with data obtained in microbiological methods to highlight the causes and extent of several influencing factors.