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29 Table 27. Comparison of the characteristics based on overall satisfaction with methods. Reproducibility Interpret Data Repeatability Applicability Ease of Use Portability Readiness Accuracy Price Characteristics of Test Methods Repeatability 1 1 1 1 1 1 1 1 1 Reproducibility 1 1 1 1 1 1 1 1 1 Accuracy 1 1 1 1 1 1 1 1 1 Cost 1 1 1 1 1 1 1 1 1 Readiness 1 1 1 1 1 1 1 1 1 Interpret Data 1 1 1 1 1 1 1 1 1 Ease of Use 1 1 1 1 1 1 1 1 1 Portability 1 1 1 1 1 1 1 1 1 Applicability 1 1 1 1 1 1 1 1 1 The results of this example show that when all characteristics than all other remaining characteristics (assigned a value of 9). were assumed to be equally important, the uncompacted void Also, applicability to different aggregate types and sizes was content of fine aggregate (UCVCF) method was at the top of considered moderately more important than other methods the priority list, mainly due to the low cost of this test. How- (assigned a value of 5). The priority list for all the character- ever, this priority order will change if the weights assigned to istics based on this consideration and the resulting priority the characteristics or to the methods are changed. vector are presented in Table 32. In another example, the accuracy of the test method was Using the weights provided in Table 25, the process described considered more important than the other characteristics, for fine aggregate angularity was followed; the resulting prior- and was thus assigned a value of 5 (based on the scale provided ity vectors presented in Table 33 for testing methods with in Table 23). The new matrix together with the calculated pri- respect to characteristics were obtained. ority vector are presented in Table 30. Multiplying the new The overall ranking of test methods used to measure characteristic's priority vector by the matrix of priority vectors coarse aggregate texture, presented in Table 34, clearly shows (resulting from comparing method with respect to the charac- that AIMS has the highest rank among all methods. As dis- teristics presented in Table 28) will result in the overall ranking cussed in the previous section, the wavelet method that AIMS of test methods presented in Table 31 for different accuracy uses in analyzing coarse aggregate texture was found to be levels of preference. unique and most accurate; it contributed significantly to It is apparent from Table 31 that when only accuracy is this ranking although some imaging methods have compa- considered moderately or absolutely more important than the rable characteristics. other characteristics, the ranking of test methods has changed; Because imaging methods will become more practical and AIMS ranked first in the priority ordering list (with more easy to use with some reasonable training, only repeatability, significant difference in the latter case). reproducibility, accuracy, and applicability should be con- The results from the two examples clearly indicate that the sidered in comparing test methods. When this criterion was selected weights can have a significant influence on the over- applied, the overall ranking of test methods measuring coarse all ranking of test methods. Therefore, it is very important aggregate texture shown in Table 34 was obtained, placing that the weights should be selected based on expert opinion AIMS on the top of the priority list and thus it would be the and judgment of the process. user's first choice for measuring coarse aggregate texture. The overall rankings of test methods presented in Table 34 show Coarse Aggregate Texture that UCVCC method has high priority when all character- istics are considered, but it becomes less favorable when price AHP was used in this example to rank the test methods becomes of less concern. that are used to measure coarse aggregate texture (UCVCC, Camsizer, WipShape, UIAIA, and AIMS). In this example, Coarse Aggregate Shape accuracy was considered moderately more important than applicability of a test method to measure all aggregate sizes and AHP was used in this example to rank test methods that types (assigned a value of 5) and absolutely more important measure coarse aggregate shape parameters and dimensional

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30 Table 28. Comparison of test methods measuring fine aggregate angularity. Test Method Characteristic Test Method UCVCF CAR PSSDA-Small Camsizer AIMS UCVCF 1 1 3 1 1 CAR 1 1 3 1 1 Repeatability PSSDA-Small 0.33 0.33 1 0.33 0.33 Camsizer 1 1 3 1 1 AIMS 1 1 3 1 1 UCVCF 1 1 3 1 1 CAR 1 1 3 1 1 PSSDA-Small 0.33 0.33 1 0.33 0.33 Reproducibility Camsizer 1 1 3 1 1 AIMS 1 1 3 1 1 UCVCF 1 1 1 0.143 0.11 CAR 1 1 1 0.143 0.11 Accuracy PSSDA-Small 1 1 1 0.143 0.11 Camsizer 7 7 7 1 0.33 AIMS 9 9 9 3 1 UCVCF 1 1 9 9 9 CAR 1 1 7 9 7 Price PSSDA-Small 0.11 0.14 1 1 1 Camsizer 0.11 0.11 1 1 1 AIMS 0.11 0.14 1 1 1 UCVCF 1 1 3 3 3 CAR 1 1 3 3 3 Readiness PSSDA-Small 0.33 0.33 1 1 1 Camsizer 0.33 0.33 1 1 AIMS 0.33 0.33 1 1 1 UCVCF 1 1 5 5 5 CAR 1 1 5 5 5 Interpretation PSSDA-Small 0.20 0.20 1 1 1 of Data Camsizer 0.20 0.20 1 1 1 AIMS 0.20 0.20 1 1 1 UCVCF 1 1 3 3 5 CAR 1 1 3 3 5 Ease of Use PSSDA-Small 0.33 0.33 1 1 3 Camsizer 0.33 0.33 1 1 3 AIMS 0.20 0.20 0.33 0.33 1 UCVCF 1 1 3 3 3 CAR 1 1 3 3 3 Portability PSSDA-Small 0.33 0.33 1 1 1 Camsizer 0.33 0.33 1 1 1 AIMS 0.33 0.33 1 1 1 UCVCF 1 1 1 1 1 CAR 1 1 1 1 1 Applicability PSSDA-Small 1 1 1 1 1 Camsizer 1 1 1 1 1 AIMS 1 1 1 1 1

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31 Table 29. Resulting priority vectors and overall ranking of test methods measuring fine aggregate angularity (assuming characteristics are equally important). Priority Vectors for Test Methods with Respect to Characteristics Reproducibility Interpret Data Repeatability Applicability Ease of Use Portability Readiness Accuracy Price Priority Vector of Overall Test Characteristics with Respect Ranking Method to Overall Satisfaction with Method UCVCF 0.231 0.231 0.051 0.444 0.333 0.385 0.342 0.333 0.20 0.111 Repeatability 0.283 UCVCF CAR 0.231 0.231 0.051 0.402 0.333 0.385 0.342 0.333 0.20 0.111 Reproducibility 0.279 CAR PSSDA- PSSDA- Small 0.077 0.077 0.051 0.052 0.111 0.077 0.130 0.111 0.20 0.111 Accuracy = 0.098 Small Camsizer 0.231 0.231 0.306 0.049 0.111 0.077 0.130 0.111 0.20 0.111 Price 0.161 Camsizer AIMS 0.231 0.231 0.540 0.052 0.111 0.077 0.056 0.111 0.20 0.111 Readiness 0.179 AIMS 0.111 Interpret Data 0.111 Ease of Use 0.111 Portability 0.111 Applicability Table 30. Comparison of characteristics with respect to overall satisfaction with method. Reproducibility Interpret Data Repeatability Applicability Ease of Use Portability Readiness Accuracy Priority Cost Characteristic Vector Repeatability 1 1 0.2 1 1 1 1 1 1 0.077 Reproducibility 1 1 0.2 1 1 1 1 1 1 0.077 Accuracy 5 5 1 5 5 5 5 5 5 0.385 Cost 1 1 0.2 1 1 1 1 1 1 0.077 Readiness 1 1 0.2 1 1 1 1 1 1 0.077 Interpret Data 1 1 0.2 1 1 1 1 1 1 0.077 Ease of Use 1 1 0.2 1 1 1 1 1 1 0.077 Portability 1 1 0.2 1 1 1 1 1 1 0.077 Applicability 1 1 0.2 1 1 1 1 1 1 0.077 Note: Accuracy is moderately more important than other characteristics. Table 31. Overall ranking of test methods measuring fine aggregate angularity for different accuracy levels of preference. Accuracy Level of Preference 1 = Equally 5 = Moderately 9 = Absolutely Test Method Important Important Important UCVCF 0.28 0.21 0.17 CAR 0.28 0.21 0.17 PSSDA-Small 0.10 0.08 0.08 Camsizer 0.16 0.21 0.23 AIMS 0.18 0.29 0.35

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32 Table 32. Comparison of characteristics with respect to overall satisfaction with method. Reproducibility Interpret Data Repeatability Applicability Ease of Use Portability Readiness Accuracy Priority Cost Characteristic Vector Repeatability 1 1 0.11 1 1 1 1 1 0.2 0.046 Reproducibility 1 1 0.11 1 1 1 1 1 0.2 0.046 Accuracy 9 9 1 9 9 9 9 9 5 0.465 Cost 1 1 0.11 1 1 1 1 1 0.2 0.046 Readiness 1 1 0.11 1 1 1 1 1 0.2 0.046 Interpret Data 1 1 0.11 1 1 1 1 1 0.2 0.046 Ease of Use 1 1 0.11 1 1 1 1 1 0.2 0.046 Portability 1 1 0.11 1 1 1 1 1 0.2 0.046 Applicability 5 5 0.2 5 5 5 5 5 1 0.211 Note: Accuracy is moderately more important than applicability and absolutely more important than other characteristics. Table 33. Priority vectors of test methods measuring coarse aggregate texture. Priority Vectors for Test Methods with Respect to Characteristics Reproducibility Interpret Data Repeatability Applicability Ease of Use Portability Readiness Accuracy Cost Test Method UCVCC 0.231 0.231 0.036 0.650 0.442 0.556 0.496 0.442 0.280 Camsizer 0.231 0.231 0.183 0.084 0.165 0.111 0.238 0.165 0.107 WipShape 0.231 0.231 0.036 0.088 0.165 0.111 0.089 0.165 0.281 UIAIA 0.231 0.231 0.372 0.088 0.063 0.111 0.089 0.165 0.051 AIMS 0.077 0.077 0.372 0.088 0.165 0.111 0.089 0.165 0.281 Table 34. Overall ranking of test methods measuring coarse aggregate texture. Only Repeatability, Test Method All Characteristics Considered Reproducibility, Accuracy, and Applicability Considered UCVCC 0.22 0.10 Camsizer 0.16 0.13 WipShape 0.13 0.10 UIAIA 0.23 0.21 AIMS 0.27 0.24