cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.6208061
title: An Improved Dynamic Contact Model for Mass–Spring and Finite Element Systems Based on Parametric Quadratic Programming Method

description: Abstract An improved dynamic contact model for mass-spring and finite element systems is proposed in this paper. The proposed model avoids the numerical troubles of spurious high-frequency oscillations for mass-spring and finite element systems in dynamic contact problems by using the parametric quadratic programming technique. The iterative process for determination of contact states are not required for each time step in the proposed method, as the contact states are transformed into the base exchanges in the solution of a standard quadratic programming problem. The proposed methodology improves stability and has good convergence behavior for dynamic contact problems. Numerical results demonstrate the validity of the proposed method.
DOI: 10.6084/m9.figshare.6208061.v1
title: An Improved Dynamic Contact Model for Mass–Spring and Finite Element Systems Based on Parametric Quadratic Programming Method

description: Abstract An improved dynamic contact model for mass-spring and finite element systems is proposed in this paper. The proposed model avoids the numerical troubles of spurious high-frequency oscillations for mass-spring and finite element systems in dynamic contact problems by using the parametric quadratic programming technique. The iterative process for determination of contact states are not required for each time step in the proposed method, as the contact states are transformed into the base exchanges in the solution of a standard quadratic programming problem. The proposed methodology improves stability and has good convergence behavior for dynamic contact problems. Numerical results demonstrate the validity of the proposed method.
DOI: 10.6084/m9.figshare.6208058
title: Performance of infill stiffened steel panel against blast loading

description: Abstract In blast loading, out-of-plane behavior of infill wall is activated initially. Contrary to other types of infill wall such as brick or concrete wall, infill steel plate wall exhibits more ductility. Since blast impulsive loading suddenly exerts a large amount of kinematic energy to infill wall, energy absorption characteristic of the infill wall should be taken into account, especially for protection of vulnerable buildings. Out-of-plane ductility of infill steel plate reduces the transmitted impulsive loading to the structure. In present study, out-of-plane behavior of infill steel panel has been studied as a sacrificial element. In-plane behavior of infill steel panel is also investigated as a lateral bearing system. In-plane action should satisfy both resistance and performance criteria. In this research, finite element analysis, including geometric and material nonlinearities is used for optimization of the steel plate thickness and stiffeners arrangement to obtain more efficient design for out-of-plane and in-plane actions. The results of analyses show that for out-of-plane action, the plate thickness and stiffeners arrangement can be determined such that on one hand, the impulse transmission can be minimized, and on the other hand, the maximum residual deformation can be limited to the predefined damage level. Additionally, the effect of stiffener arrangement on the performance of in-plane are studied and some practical rules have been derived for designing the infill steel panel against blast.
DOI: 10.6084/m9.figshare.6208058.v1
title: Performance of infill stiffened steel panel against blast loading

description: Abstract In blast loading, out-of-plane behavior of infill wall is activated initially. Contrary to other types of infill wall such as brick or concrete wall, infill steel plate wall exhibits more ductility. Since blast impulsive loading suddenly exerts a large amount of kinematic energy to infill wall, energy absorption characteristic of the infill wall should be taken into account, especially for protection of vulnerable buildings. Out-of-plane ductility of infill steel plate reduces the transmitted impulsive loading to the structure. In present study, out-of-plane behavior of infill steel panel has been studied as a sacrificial element. In-plane behavior of infill steel panel is also investigated as a lateral bearing system. In-plane action should satisfy both resistance and performance criteria. In this research, finite element analysis, including geometric and material nonlinearities is used for optimization of the steel plate thickness and stiffeners arrangement to obtain more efficient design for out-of-plane and in-plane actions. The results of analyses show that for out-of-plane action, the plate thickness and stiffeners arrangement can be determined such that on one hand, the impulse transmission can be minimized, and on the other hand, the maximum residual deformation can be limited to the predefined damage level. Additionally, the effect of stiffener arrangement on the performance of in-plane are studied and some practical rules have been derived for designing the infill steel panel against blast.
DOI: 10.6084/m9.figshare.6208055
title: An enriched meshless finite volume method for the modeling of material discontinuity problems in 2D elasticity

description: Abstract A 2D formulation for incorporating material discontinuities into the meshless finite volume method is proposed. In the proposed formulation, the moving least squares approximation space is enriched by local continuous functions that contain discontinuity in the first derivative at the location of the material interfaces. The formulation utilizes space-filling Voronoi-shaped finite volumes in order to more intelligently model irregular geometries. Numerical experiments for elastostatic problems in heterogeneous media are presented. The results are compared with the corresponding solutions obtained using the standard meshless finite volume method and element free Galerkin method in order to highlight the improvements achieved by the proposed formulation. It is demonstrated that the enriched meshless finite volume method could alleviate the expecting oscillations in derivative fields around the material discontinuities. The results have revealed the potential of the proposed method in studying the mechanics of heterogeneous media with complex micro-structures.
DOI: 10.6084/m9.figshare.6208052
title: Behavior of fiber reinforced mortar composites under impact load

description: Abstract This paper presents results of the experimental study on the behavior of plain and fiber reinforced cement mortars with different fibers under static and impact compressive load. Glass, polypropylene and carbon fibers were used in equal dosage by mass. The impact test was conducted using an impact tower with drop hammer, which represented the modification of the split-Hopkinson pressure bar system, with strain rates ranging from approximately 35 to 60 s-1. The results of the static test and impact test with two different drop heights were compared and discussed. Among other, it has been concluded that the tested fiber reinforced mortars had no greater static and impact strength compared to the plain mortar. Only their ductility was increased at both static and impact failure. Strengths and ductility of all composite specimens were similar, i.e. without the effect of fiber type. With the increase of strain rate, compressive strength is increased and ductility is decreased for all tested specimens.
DOI: 10.6084/m9.figshare.6208055.v1
title: An enriched meshless finite volume method for the modeling of material discontinuity problems in 2D elasticity

description: Abstract A 2D formulation for incorporating material discontinuities into the meshless finite volume method is proposed. In the proposed formulation, the moving least squares approximation space is enriched by local continuous functions that contain discontinuity in the first derivative at the location of the material interfaces. The formulation utilizes space-filling Voronoi-shaped finite volumes in order to more intelligently model irregular geometries. Numerical experiments for elastostatic problems in heterogeneous media are presented. The results are compared with the corresponding solutions obtained using the standard meshless finite volume method and element free Galerkin method in order to highlight the improvements achieved by the proposed formulation. It is demonstrated that the enriched meshless finite volume method could alleviate the expecting oscillations in derivative fields around the material discontinuities. The results have revealed the potential of the proposed method in studying the mechanics of heterogeneous media with complex micro-structures.
DOI: 10.6084/m9.figshare.6208052.v1
title: Behavior of fiber reinforced mortar composites under impact load

description: Abstract This paper presents results of the experimental study on the behavior of plain and fiber reinforced cement mortars with different fibers under static and impact compressive load. Glass, polypropylene and carbon fibers were used in equal dosage by mass. The impact test was conducted using an impact tower with drop hammer, which represented the modification of the split-Hopkinson pressure bar system, with strain rates ranging from approximately 35 to 60 s-1. The results of the static test and impact test with two different drop heights were compared and discussed. Among other, it has been concluded that the tested fiber reinforced mortars had no greater static and impact strength compared to the plain mortar. Only their ductility was increased at both static and impact failure. Strengths and ductility of all composite specimens were similar, i.e. without the effect of fiber type. With the increase of strain rate, compressive strength is increased and ductility is decreased for all tested specimens.
DOI: 10.6084/m9.figshare.6208049
title: Convective Intraseasonal Oscillations beteween Indian-Pacific and Northeasth Brazil Regions: Some Observational and Models Characteristics

description: Abstract This study investigated with observations and modeling using daily data of Long-Wave Radiation (RLW) the favorable phase to the convective activity associated with the low-frequency intrassazonal atmospheric variability known with Madden-Julian Oscillation (MJO) between the Indian Pacific region (INDI-PAC) and Northeastern Brazil (NEB) from November to May period of 1982 to 2013. The model used was the Global Ocean-Land-Atmosphere Model (OLAMV3.3) and observations were used for data generated by satellites by the Climate Prediction Center / National Ocean Atmospheric Admistration. The objective was to verify the time of the zonal band shift of these convective oscillations from its initial pulse, INDI-PAC region until reaching NEB. The data filtering method known as Lanczos Filter was applied in the band of 20-70 days in order to eliminate high oscillations, synoptic scales) and low frequencies (annual or more). Spectral characteristics using Wavelet analyzes showed that these oscillations between 20-70 days, from November to May, have a maximum energy spectrum in the observed data centered in the period of 8-16 pentads, end of December and beginning of April. The OLAM showed an advance of this maximum energy peak in the INDI-PAC region and an extension on the date of arrival in the NEB, meaning a delay, being that date for the end of April and May of this maximum of energy on the NEB.
DOI: 10.6084/m9.figshare.6208046
title: Applicability of TRMM Precipitation for Hydrologic Modeling in a Basin in the Northeast Brazilian Agreste

description: Abstract Determining precipitation using remote sensing is gaining space in hydrologic studies, helping make up for the lack of data in many regions of Brazil. The products from satellite TRMM (Tropical Rainfall Measuring Mission) are widely applied in studies in Brazil, but there are still few results about their applicability for hydrologic modeling in the Northeast Region, which is characterized by an irregular precipitation regime. The objective of this study is to evaluate the feasibility of using the TRMM 3B42 V7 data for hydrologic modeling in the Japaratuba river basin in Sergipe at three timescales: daily, every ten days, and monthly. The comparative analysis between the rainfall data from rain gauges and TRMM did not indicate satisfactory adequacy at these studied scales, since the TRMM data underestimated the total rainfall for all stations used in the study. However, for the hydrologic modeling, acceptable values were obtained for the efficiency coefficients evaluated only for the ten-day and monthly scales.
DOI: 10.6084/m9.figshare.6208049.v1
title: Convective Intraseasonal Oscillations beteween Indian-Pacific and Northeasth Brazil Regions: Some Observational and Models Characteristics

description: Abstract This study investigated with observations and modeling using daily data of Long-Wave Radiation (RLW) the favorable phase to the convective activity associated with the low-frequency intrassazonal atmospheric variability known with Madden-Julian Oscillation (MJO) between the Indian Pacific region (INDI-PAC) and Northeastern Brazil (NEB) from November to May period of 1982 to 2013. The model used was the Global Ocean-Land-Atmosphere Model (OLAMV3.3) and observations were used for data generated by satellites by the Climate Prediction Center / National Ocean Atmospheric Admistration. The objective was to verify the time of the zonal band shift of these convective oscillations from its initial pulse, INDI-PAC region until reaching NEB. The data filtering method known as Lanczos Filter was applied in the band of 20-70 days in order to eliminate high oscillations, synoptic scales) and low frequencies (annual or more). Spectral characteristics using Wavelet analyzes showed that these oscillations between 20-70 days, from November to May, have a maximum energy spectrum in the observed data centered in the period of 8-16 pentads, end of December and beginning of April. The OLAM showed an advance of this maximum energy peak in the INDI-PAC region and an extension on the date of arrival in the NEB, meaning a delay, being that date for the end of April and May of this maximum of energy on the NEB.
DOI: 10.6084/m9.figshare.6208046.v1
title: Applicability of TRMM Precipitation for Hydrologic Modeling in a Basin in the Northeast Brazilian Agreste

description: Abstract Determining precipitation using remote sensing is gaining space in hydrologic studies, helping make up for the lack of data in many regions of Brazil. The products from satellite TRMM (Tropical Rainfall Measuring Mission) are widely applied in studies in Brazil, but there are still few results about their applicability for hydrologic modeling in the Northeast Region, which is characterized by an irregular precipitation regime. The objective of this study is to evaluate the feasibility of using the TRMM 3B42 V7 data for hydrologic modeling in the Japaratuba river basin in Sergipe at three timescales: daily, every ten days, and monthly. The comparative analysis between the rainfall data from rain gauges and TRMM did not indicate satisfactory adequacy at these studied scales, since the TRMM data underestimated the total rainfall for all stations used in the study. However, for the hydrologic modeling, acceptable values were obtained for the efficiency coefficients evaluated only for the ten-day and monthly scales.
DOI: 10.6084/m9.figshare.6208037
title: zCoinfections by Leishmania infantum, Neospora caninum and Toxoplasma gondii in necropsied dogs from the central region of Rio Grande do Sul, Brazil

description: ABSTRACT The present paper is aimed to determine the presence of antibodies for Leishmania infantum, Neospora caninum and Toxoplasma gondii by indirect immunofluorescence (IIF) in dogs (n=78) from the central region in the state of Rio Grande do Sul necropsied in the Veterinary Hospital from Universidade Federal de Santa Maria (UFSM). The data was evaluated regarding epidemiological, anatomic, and histopathologic findings. Of the total animals evaluated, 67.9% (53/78) showed seropositivity for at least one agent. The occurrence of antibodies to L. infantum, N. caninum and T. gondii was 33.3% (26/78) 37.1% (29/78) and 43.5% (34/78), respectively. The mono infections were detected in 9.4% (5/53) of L. infantum, 18.8% (10/53) for N. caninum and 20.7% (11/53) T. gondii. The coinfections occurred in 50.9% (27/53) of animals. There were not anatomical and histopathological lesions regarding these surveyed agents, characterizing them as subclinical animals. The results confirmed the exposition of dogs to these protozoa in the central region of the RS, highlighting the circulation of the causer agent of leishmaniasis in an area considered harmless for the disease.
DOI: 10.6084/m9.figshare.6208037.v1
title: zCoinfections by Leishmania infantum, Neospora caninum and Toxoplasma gondii in necropsied dogs from the central region of Rio Grande do Sul, Brazil

description: ABSTRACT The present paper is aimed to determine the presence of antibodies for Leishmania infantum, Neospora caninum and Toxoplasma gondii by indirect immunofluorescence (IIF) in dogs (n=78) from the central region in the state of Rio Grande do Sul necropsied in the Veterinary Hospital from Universidade Federal de Santa Maria (UFSM). The data was evaluated regarding epidemiological, anatomic, and histopathologic findings. Of the total animals evaluated, 67.9% (53/78) showed seropositivity for at least one agent. The occurrence of antibodies to L. infantum, N. caninum and T. gondii was 33.3% (26/78) 37.1% (29/78) and 43.5% (34/78), respectively. The mono infections were detected in 9.4% (5/53) of L. infantum, 18.8% (10/53) for N. caninum and 20.7% (11/53) T. gondii. The coinfections occurred in 50.9% (27/53) of animals. There were not anatomical and histopathological lesions regarding these surveyed agents, characterizing them as subclinical animals. The results confirmed the exposition of dogs to these protozoa in the central region of the RS, highlighting the circulation of the causer agent of leishmaniasis in an area considered harmless for the disease.
DOI: 10.6084/m9.figshare.6208034
title: ENZYMATIC BIODIESEL SYNTHESIS FROM ACID OIL USING A LIPASE MIXTURE

description: The conventional biodiesel production process has some disadvantages. It is necessary to use refined vegetable oils with low free fatty acids (FFAs) content. An alternative route is to use low-cost acid oils in an enzymatic process. The use of lipases allows simultaneous esterification of FFAs and transesterification of triglycerides present in raw material forming alkyl esters. The aim of this work was to study the production of biodiesel using soybean oils with different acid contents (Acid Value of 8.5, 50, 90) and ethanol catalyzed by commercial immobilized lipases (Novozym 435, Lipozyme RM IM and Lipozyme TL IM). A significant decrease of acid value was observed mainly with Novozym 435 and Lipozyme RM IM. The use of a mixture of two immobilized lipases was also investigated to decrease catalyst cost and increase the amount of ester produced. The three commercial immobilized lipases were mixed in a dual system and tested for biodiesel synthesis from acid oil (AV of 8.5, 50 and 90). A positive synergistic effect occurred mainly for Lipozyme TL IM (1,3-specific lipase) and Novozym 435 (non-specific lipase) blend. The ester content doubled when this lipase mixture was used in ethanolysis of acid oil with AV of 90.
DOI: 10.6084/m9.figshare.6208034.v1
title: ENZYMATIC BIODIESEL SYNTHESIS FROM ACID OIL USING A LIPASE MIXTURE

description: The conventional biodiesel production process has some disadvantages. It is necessary to use refined vegetable oils with low free fatty acids (FFAs) content. An alternative route is to use low-cost acid oils in an enzymatic process. The use of lipases allows simultaneous esterification of FFAs and transesterification of triglycerides present in raw material forming alkyl esters. The aim of this work was to study the production of biodiesel using soybean oils with different acid contents (Acid Value of 8.5, 50, 90) and ethanol catalyzed by commercial immobilized lipases (Novozym 435, Lipozyme RM IM and Lipozyme TL IM). A significant decrease of acid value was observed mainly with Novozym 435 and Lipozyme RM IM. The use of a mixture of two immobilized lipases was also investigated to decrease catalyst cost and increase the amount of ester produced. The three commercial immobilized lipases were mixed in a dual system and tested for biodiesel synthesis from acid oil (AV of 8.5, 50 and 90). A positive synergistic effect occurred mainly for Lipozyme TL IM (1,3-specific lipase) and Novozym 435 (non-specific lipase) blend. The ester content doubled when this lipase mixture was used in ethanolysis of acid oil with AV of 90.
DOI: 10.6084/m9.figshare.6208031
title: Effect of acute and chronic caloric heat stress on oocyte quality of adapted breeds cattle

description: ABSTRACT In tropical regions, the use of adapted breeds has been a strategy to minimize the effect of heat stress (HS) in cattle. However, information quantifying stress and its effect on reproduction of these breeds is lacking. The aim of this study was to evaluate the quality of the recovered oocyte and some physiological parameters that indicate HS in adapted breed. Bos taurus x Bos indicus (n=6) and Pantaneira (n=12) cows, located in the transition region between Cerrado and Brazilian Pantanal, underwent follicular aspiration guided by ultrasound (OPU) in different weather conditions. Eight sessions of OPU were carried out, with a minimum interval of 7 days and maximum 54 days between sessions. For weather characterization, the temperature and humidity index (THI) was calculated. THI of the day of OPU, 7 days before and 60 days before each session were calculated. The physiological parameters and oocyte viability of Girolando and Pantaneira cows were not negatively influenced under ITU between 72 and 78. The chronic HS (60 days)may affect the oocyte viability of Pantaneira donors when ITU is over 75.
DOI: 10.6084/m9.figshare.6208031.v1
title: Effect of acute and chronic caloric heat stress on oocyte quality of adapted breeds cattle

description: ABSTRACT In tropical regions, the use of adapted breeds has been a strategy to minimize the effect of heat stress (HS) in cattle. However, information quantifying stress and its effect on reproduction of these breeds is lacking. The aim of this study was to evaluate the quality of the recovered oocyte and some physiological parameters that indicate HS in adapted breed. Bos taurus x Bos indicus (n=6) and Pantaneira (n=12) cows, located in the transition region between Cerrado and Brazilian Pantanal, underwent follicular aspiration guided by ultrasound (OPU) in different weather conditions. Eight sessions of OPU were carried out, with a minimum interval of 7 days and maximum 54 days between sessions. For weather characterization, the temperature and humidity index (THI) was calculated. THI of the day of OPU, 7 days before and 60 days before each session were calculated. The physiological parameters and oocyte viability of Girolando and Pantaneira cows were not negatively influenced under ITU between 72 and 78. The chronic HS (60 days)may affect the oocyte viability of Pantaneira donors when ITU is over 75.