ABSTRACT
OBJECTIVE: The objective of this study was to develop a model for estimating the carcass weight of Hanwoo cattle as a function of body measurements using three different modeling approaches: i) multiple regression analysis, ii) partial least square regression analysis, and iii) a neural network. METHODS: Data from a total of 134 Hanwoo cattle were obtained from the National Institute of Animal Science in South Korea. Among the 372 variables in the raw data, 20 variables related to carcass weight and body measurements were extracted to use in multiple regression, partial least square regression, and an artificial neural network to estimate the cold carcass weight of Hanwoo cattle by any of seven body measurements significantly related to carcass weight or by all 19 body measurement variables. For developing and training the model, 100 data points were used, whereas the 34 remaining data points were used to test the model estimation. RESULTS: The R2 values from testing the developed models by multiple regression, partial least square regression, and an artificial neural network with seven significant variables were 0.91, 0.91, and 0.92, respectively, whereas all the methods exhibited similar R2 values of approximately 0.93 with all 19 body measurement variables. In addition, relative errors were within 4%, suggesting that the developed model was reliable in estimating Hanwoo cattle carcass weight. The neural network exhibited the highest accuracy. CONCLUSION: The developed model was applicable for estimating Hanwoo cattle carcass weight using body measurements. Because the procedure and required variables could differ according to the type of model, it was necessary to select the best model suitable for the system with which to calculate the model.
ABSTRACT
We assessed the patellar inferior pole (PIP) as a new landmark of the anteromedial (AM) instrumental portal for arthroscopic surgery of the posterior horn of the medial meniscus (PHMM). Fifty normal right knees in young adults (group 1) and 50 knees from adults of various ages undergoing arthroscopic surgery for relatively simple intra-articular pathologies or diagnosis (group 2) were included. In both groups, on 30 degrees flexion true lateral plain radiographs, the line passing through the PIP and the distalmost femoral condyle; (Kim's AM portal line) was drawn, then the length from the anterior end of the medial tibial plateau (MTP) to the meeting point of Kim's AM portal line with the MTP (length C) and the anteroposterior length of the MTP (length D) was measured. The length C was then taken as a percentage of length D (C-D percentage), and the distance between the PIP and the anterior joint line (length E) was measured. The average C-D percentages and lengths E were 110+/-33.6% and 14.8+/-3.8 mm in group 1, and 114+/-38.4% and 16.3+/-4.7 mm in group 2. There were no significant differences in the C-D percentages or the lengths E between the two groups. Also, in group 2, the AM portal was made at the PIP level, and we assessed the relative ease of instrument insertion to reach the PHMM and the body of the lateral meniscus (LM) using a scoring system of our own design. Fort-nine and 48 knees were classified as good for the PHMM and for the body of the LM, respectively. We concluded that the PIP can be used as a skin landmark for arthroscopic surgery of the PHMM.