• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.123-124
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• 2023

Despite the acuuracy, stability, and economic feasibility of geomagnetic field-based indoor positioning, its applicability in construction sites needs to be thoroughly discussed due to the issue of distortion of geomagnetic fields around ferromagnetic objects such as rebars. In this study, the possibility of applying the geomagnetic field-based indoor positioning in construction sites was reviewed through the Student's t-test after measuring the changes in geomagnetic field values depending on the presence or absence of rebars. The statistical analysis revealed that there is a high probability (over 80%) of significant changes in geomagnetic field values when measuring points are located within 60cm from the rebars. On the other hand, the probability of minimal changes in geomagnetic field values is over 90% when measuring points are located more than 60cm from the rebars. This suggests the application of geomagnetic-based indoor positioning in construction sites would be possible if the issue of distortion in geomagnetic field values near rebars within 60cm is resolved.

• Animal Bioscience
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• v.36 no.9
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• pp.1327-1335
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• 2023

Objective: When evaluating individuals with the same parent and no phenotype by pedigree best linear unbiased prediction (BLUP), it is difficult to explain carcass grade difference and select individuals because they have the same value in pedigree BLUP (PBLUP). However, single step GBLUP (ssGBLUP), which can estimate the breeding value suitable for the individual by adding genotype, is more accurate than the existing method. Methods: The breeding value and accuracy were estimated with pedigree BLUP and ssGBLUP using pedigree and genotype of 408 Hanwoo cattle from 16 families with the same parent among siblings produced by fertilized egg transplantation. A total of 14,225 Hanwoo cattle with pedigree, genotype and phenotype were used as the reference population. PBLUP obtained estimated breeding value (EBV) using the pedigree of the test and reference populations, and ssGBLUP obtained genomic EBV (GEBV) after constructing and H-matrix by integrating the pedigree and genotype of the test and reference populations. Results: For all traits, the accuracy of GEBV using ssGBLUP is 0.18 to 0.20 higher than the accuracy of EBV obtained with PBLUP. Comparison of EBV and GEBV of individuals without phenotype, since the value of EBV is estimated based on expected values of alleles passed down from common ancestors. It does not take Mendelian sampling into consideration, so the EBV of all individuals within the same family is estimated to be the same value. However, GEBV makes estimating true kinship coefficient based on different genotypes of individuals possible, so GEBV that corresponds to each individual is estimated rather than a uniform GEBV for each individual. Conclusion: Since Hanwoo cows bred through embryo transfer have a high possibility of having the same parent, if ssGBLUP after adding genotype is used, estimating true kinship coefficient corresponding to each individual becomes possible, allowing for more accurate estimation of breeding value.