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Showing 3 results for Carneiro


Volume 13, Issue 3 (10-2013)
Abstract

Nowadays, buildings are built without required separation distance as many engineers do not consider the building pounding effects. If adjacent buildings are not separated properly from each other, pounding can occur upon earthquake occurrence, and severe damages to the buildings can be observed even if they are well designed and constructed. Engineers should realize that building pounding is a serious hazard and it has to be considered during design and construction of buildings. There are many residential building complexes, service office, agencies, schools and hospital in cities around the world which are located next to each other as the cost of land is high. In this term, hospitals with emergency facilities and emergency centers have to be protected against the damages due to the significance of such structures prior and after earthquake. Many researchers have studied building pounding to calculate the dissipated energy and the impact force between two buildings during earthquake. For this challenge, they need to have a link element, which describes impact by using spring and dashpot. Several mathematical equations were suggested to calculate two mentioned parameters. In this paper, based on mathematic relation, a new relation of damping term of impact formula is simulated to measure impact force and energy dissipation. The results of this formula are compared with another suggested formula. As it was mentioned, different materials used in building constructions cause various dynamic behaviors during earthquake. Concrete structures are typically more rigid than steel structures in similar conditions. Consequently, lateral displacements of concrete buildings may also be less than lateral displacements of similar steel structures as stiffness of concrete buildings causes decrease in natural periods during earthquake. Naturally, large lateral nonlinear displacements under time history lateral loading in concrete structures may not be observed. Buildings can collide with adjacent buildings in left and right directions. For concrete buildings, however, the impact of pounding may be more significant than those on steel structures in most situations. Many researchers have suggested new relations in terms of impact to increase the dissipated energy. Based on mathematic relation, they showed that energy dissipation depends significantly on stiffness, impact velocity and coefficient of restitution. For this challenge, by using a suggested link element, a new formula is presented to calculate the impact force and energy dissipation. To optimize the results of dissipated energy, a new relation between CR and impact velocity is suggested. As it seems that it is a need to have a reference curve to select impact velocity based on coefficient of restitution, several impact velocity and CR were evaluated. Using this curve, all of results can be optimized. Finally, a new equation of motion is assumed to select the best impact velocity and coefficient of restitution.

Volume 19, Issue 7 (Supplementary Issue - 2017)
Abstract

Knowledge of buffalo growth curves is essential for improving reproductive management, nutritional strategies and identifying the best slaughter age. We provided the first joint study comparing growth curves of the three major buffalo breeds. Additionally, we used principal component analysis and Biplot graphics to evaluate the degree of similarity between the groups (breed by sex) and their relationship with mature weight, maturation rate and weight at different ages. The dataset included 8,550 weight records from 1,391 Jaffarabadi, Mediterranean and Murrah buffaloes. The Bertalanffy model had the best fit. The mature weights were 696.64±8.50 and 678.53±9.44 kg (Mediterranean), 716.26±48.54 and 629.28±32.11 kg (Jaffarabadi) and 694.69±17.97 and 556.53±15.49 kg (Murrah) male and female, respectively, by Bertalanffy model. All breeds reaching 75% of mature weight in less than two years. Murrah females were particularly productive, having high precocity and low weight maturity - important biotypes for milk production. Murrah males showed intermediate characteristics, and high potential for meat production in dairy herds. Mediterranean animals showed high weight gain, median precocity and medium to high weight at maturity, supporting its status as the main breed for beef production in Brazil. Jaffarabadi males had high mature weight, slow growth in the first year of life followed by high growth thereafter. Female Jaffarabadi were smaller and showed a similar level of precocity to Mediterranean animals. Buffaloes in Brazil have traditionally been used for milk production; however, our study clearly demonstrates that all three breeds have appropriate characteristics for meat production.

Volume 22, Issue 4 (6-2020)
Abstract

The aim of this study was to determine the differences in digit sizes from both pelvic limbs of 169 dairy cows of different genetic groups (Holstein, Jersey, Brown Swiss, and Jersolando), in lactating and non-lactating conditions, and their relation with diseases. Images were taken from the plantar view of the lateral and medial digits, and the length and width of the sole and bulb were then measured. Variables were discarded and factors for analysis were defined. Data were defined according to the highest coefficients and used to discriminate genetic groups and their association with indexes of foot diseases and productive performance. The Chi-square test showed that higher involvement occurred in lactating cows and in the right pelvic limb. Differences among all genetic groups were observed regarding the variables body weight, productive longevity, incidence of foot diseases, and generated factors. The Jersey breed was isolated from the other genetic groups because it presented lower coefficients for all variables; Holstein and Brown Swiss presented the highest morphometric measures of the digits, a higher body weight, and productive longevity, and higher rates of foot diseases. The Jersolando presented intermediate values ​​between those of the two breeds from which it originated. The susceptibility to foot diseases is associated with breed, lactational stage, body weight, and with the morphometric parameters of the digits.

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