bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inverse Modeling Applied for Material Characterization of Powder Materials
Authors: Andersson Daniel C. , Lindskog Per , Larsson Per-Lennart 
Published: October 2014

Abstract
An investigation is performed concerning the applicability of inverse procedures, using optimization and simple experiments, for characterization of WC/Co powder materials. The numerical procedure is combined with uniaxial die-compaction experiments using an instrumented die, which allows direct measurement of the distribution of radial stress during the experiments. Finite-element (FE) methods and an advanced constitutive description of powder materials are relied upon to model the compaction experiment. Optimization using a surrogate model is used to determine some of the parameters in the constitutive description. These parameters in the material model are said to be found (with some accuracy) if the output from the FE simulation is similar to the experimental data. It is found that even though a complete constitutive description of the powder materials investigated cannot be achieved using this approach, many important material parameters can be determined with good accuracy.
Experimental Analysis of the Influence of Toe Angle in Relation to Tire Pressure in the Measurement of Brake Forces at Spanish Ministry of Transport Test Facilities
Authors: Senabre C. , Velasco E. , Valero S. 
Published: October 2014

Abstract
Currently, the International Committee of Vehicle Inspection (CITA) requires that the status of brakes be checked at Ministry of Transport (MOT) stations. Article 14 of CITA Law No. 29237 states that “the driver of the vehicle must present the vehicle to an MOT station with the right tire pressure.” Unfortunately, in the 2009 MOT Procedure Manual, a procedure for checking tire angles in brake tests at MOT stations is not indicated. In this paper, we present an investigation of the influence of toe angle (the symmetric angle that each wheel makes with the longitudinal axis of the vehicle, also known as tracking or convergence) in relation to the inflation pressure of tires on the measurements of brake force tests at MOT facilities.
Slip Prediction Accuracy and Bias of the SATRA STM 603 Whole Shoe Tester
Authors: Blanchette Mark G. , Powers Christopher M. 
Published: October 2014

Abstract
The primary purpose of this study was to determine the ability of the SATRA STM 603 whole shoe tester to predict slip potential using EN ISO 13287 test parameters. A secondary purpose was to determine whether altering EN ISO 13287 test parameters improves slip prediction accuracy and assessment bias. The utilized coefficient of friction and kinematic data were recorded for 34 healthy adults. Each subject ambulated across water-contaminated porcelain tile, and the slip outcomes were recorded. Available friction testing was performed with the SATRA STM 603 using EN ISO 13287 test parameters and 44 permutations of EN ISO 13287 test parameters that varied with respect to normal force, sliding velocity, and shoe contact angle. Results revealed that the EN ISO 13287 model exhibited positive coefficient-of-friction assessment bias (0.132) and predicted only 35 % of slip events. Modifying EN ISO 13287 test parameters decreased assessment bias (0.000) and increased slip prediction accuracy to 74 % of slip events.
Influence of Rejuvenators on the Physical Properties of RAP Binders
Authors: Huang Shin-Che , Qin Qian , Grimes Will R. , Pauli Adam Troy , Glaser Ron 
Published: October 2014

Abstract
An experimental study was conducted to characterize the physical properties of rejuvenated RAP binders at low, intermediate, and high temperatures via dynamic shear rheometer (DSR) and differential scanning calorimeter (DSC) measurements. A dynamic shear rheometer was used to conduct frequency sweeps at temperatures ranging from −20°C to 80°C in increments of 20°C. The effect of rejuvenators on the thermal behavior of highly aged asphalt binders was also studied by temperature-modulated differential scanning calorimetry (TMDSC). Both DSR and DSC indicate that the interaction between rejuvenators and asphalt binders has different softening effects on RAP binders. Of the four concentrations used in this study, 10 wt. % of rejuvenator appears to be the optimum. 30 wt. % of rejuvenator onto highly aged binder results in material softer than the original RTFO-aged asphalt binders. Rheological results suggest that vegetable oil base and maltene base rejuvenators provide similar flow property improvement for highly aged binders. The DSC results indicate that vegetable-oil-based rejuvenator improves thermal behavior the most as compared to the other two rejuvenators. The results obtained from rheological testing agree with the results from DSC.
Studies of Absorption in Sanitary Protective Gloves
Authors: Fraga F. , Rodríguez-Núñez E. , Díaz de Freijo S. , Martínez-Ageitos J. M. , Suárez-Pereiro F. 
Published: October 2014

Abstract
In this article, we calculated the mass saturation and the diffusion coefficient of the polymeric systems used in protective gloves for distilled water and artificial sweat. It can be seen that the absorption is greater when the gloves are immersed in distilled water, particularly for nitrile and neoprene gloves. This happens because the crystals formed with artificial sweat are positioned on the surface of the glove's pores to partly prevent liquid absorption. A differential scanning calorimeter was used to determine the glass transition temperature for amorphous polymer, nitrile gloves, vinyl gloves, exploration latex gloves and surgical latex gloves, and the melting temperature for semi-crystalline neoprene gloves. The plasticizing results obtained for immersion of distilled water were similar to those of immersion in artificial sweat. UV-visible spectrometry can be applied to an indirect technique to test the glove's permeability. The results show that in the case of the nitrile, vinyl, exploration latex, and surgical latex, a migration of the indicator through the glove takes place. In contrast, no migration happens in the case of the neoprene. In nitrile gloves and vinyl gloves, a greater migration is observed. This could indicate a greater permeability of this type of glove. In the case of surgical latex and exploration latex, a migration with a relatively small value is observed. Using a scanning electron microscope (SEM), we observed the structural modifications that polymers undergo during their exposure to artificial sweat. The surgical latex immersed in artificial sweat shows the size increase in the pores, while the corresponding nitrile gloves do not vary. This fact could be related to the results obtained in the study of absorption that showed that surgical latex gloves had greater plasticizing.
Performance Characteristics Comparisons of Various Asphalt Mixture Technologies
Authors: Xiao Feipeng , Amirkhanian Serji , Wang Hainian , Wang Hao 
Published: October 2014

Abstract
A laboratory investigation was carried out to study the effects of various compaction technologies on moisture susceptibility, rutting resistance, and fatigue characteristics of various asphalt mixtures. The methodologies used in this study included three technologies such as common hot mix asphalt (HMA), warm mix (WMA), and half-warm mix asphalt (HWMA) technologies. In addition, in terms of WMA and HWMA mixtures, a foaming technology was used to produce the samples. The experimental design for WMA and HWMA included one aggregate moisture contents (∼0.5 % by weight of the dry mass of the aggregate), three lime contents (0 %, 1 % and 2 % lime by weight of dry aggregate), and 2 % foaming water content. For HMA, 1 % lime content and completely dried aggregate were used. Three aggregate sources (designated as A, B, and C) and one PG 64-22 binder were used in this study. A total of 9 Superpave mix designs and 21 mixtures were completed. A total of 84 indirect tensile strength (ITS) samples, 126 asphalt pavement analyzer (APA) samples, and 30 fatigue beams were tested in this research. The major properties such as gyration number, ITS, tensile strength ratio (TSR), rut depth, deformation, toughness, as well as fatigue life were measured and computed for all mixtures. The test results indicated that various compaction technologies would slightly affect the Superpave mix design and obviously have an influence on gyration number, ITS values, rut depth, flow, toughness, and fatigue life of various mixtures regardless of aggregate source and lime content. In addition, the aggregate source significantly affected the ITS and rutting resistance in this study.
Ionic Conductivity of a Carbonate–Ion Conductor
Authors: Liu Tao , Lin Li , Yu Jingkun 
Published: October 2014

Abstract
A systematic investigation on ionic conductivity of a carbonate–ion conductor has been reported. La0.8Sr0.2Ga0.83Mg0.17O2.815 (LSGM), LiKCO3 (MC), and LiNiO2 were prepared by solid–state reaction, respectively. A dual–phase LSGM and MC were mixed LSGM–MC. The effect of temperature on impedance spectra and effective ionic conductivity of LSGM–MC was investigated. The effect of electrode materials on impedance spectra was also investigated. The results showed that there was no solid reaction between LSGM, MC, and LiNiO2. As the physical state of MC transformed from solid state to liquid state, ionic conductivity of the carbonate–ion conductor was dependent on temperature. There was a significant difference for MC in three temperature range: t ≤ 460°C, 460°C &lt; t &lt; 486°C, and t ≥ 486°C. DTA analysis showed that temperatures of melting and solidification agree with those of ionic conductivity. Compared with Ag and LSGM–MC–LiNiO2, Au is a better cathode material.
An Improved Short-Beam Method for Measuring Multiple Constitutive Properties for Composites
Authors: Carpentier Paige , Makeev Andrew , Liu Liu , Shonkwiler Brian 
Published: October 2014

Abstract
The short beam shear (SBS) test method combined with digital image correlation (DIC) deformation measurement is used in this work to study constitutive properties of the IM7/8552 carbon/epoxy composite material system. Dependence of the shear stress approximation on the SBS specimen span-to-thickness (s/t) ratio has been investigated. A stress model developed in a previous study is expanded to account for this dependency. In addition, the effect of nonzero transverse normal stresses on a simple closed-form approximation for tensile and compressive axial moduli has been assessed. Results from the expanded closed-form solution verify that transverse normal stress has little influence on the measurement of the axial moduli. Also, the SBS test setup has been refined as a result of the sensitivity of the measured axial strain distribution to the specimen alignment in the test fixture. The test results obtained in this work are compared with previously published results to demonstrate the ability of a single unidirectional SBS test to capture multiple constitutive properties including axial tensile and compressive moduli, the nonlinear shear stress–strain response in the plane of loading, and to show that measured material properties do not depend on the test specimen size.
Optimal Control of the Machine Repair Problem with Removable Repairman Subject to Working Breakdowns
Authors: Yen Tseng-Chang , Wu Haitao , Wang Kuo-Hsiung , Chou Wen-Kuang 
Published: October 2014

Abstract
This paper deals with a single removable repairman in the machine repair problem with warm standbys and working breakdowns. We assume that the repairman can be subject to working breakdowns only when there is at least one failed machine in the system. Applying the matrix-analytic method, we develop the steady-state probabilities of the number of failed machines in the system as well as several system-performance measures. We construct a cost model to compute the optimal threshold N, and the joint optimal values for the fast and slow service rates simultaneously by a two-stage optimization method whose effectiveness is proved by numerical results. Moreover, we also analyze the sensitivity with numerical illustrations based on different system parameter values.
Estimating Process Capability Index Cp with Various Sample Types: A Practical Implementation
Authors: Wu C. H. , Pearn W. L. 
Published: October 2014

Abstract
Process precision index Cp has been used widely in the manufacturing industry for measuring process potential and precision. In practice, sample data with various types such as one single random sample, multiple random samples, control chart samples, and samples with gauge measurement errors may be employed to estimate the Cp index for evaluating the process potential capability. If the process is perfectly centered in the specification range, the percentage of process non-conforming (%NC) can be expressed by Cp index. In this paper, a review for estimating and testing of Cp index is presented. Some efficient MATLAB programs and illustrative examples are also provided for each type of sample data.
In-Situ Field Measurements and Numerical Model Identification of a Multi-Span Steel Railway Bridge
Authors: Caglayan Ozden , Ozakgul Kadir , Tezer Ovunc , Piroglu Filiz 
Published: October 2014

Abstract
In this paper, in situ field measurements and analytical model verification studies of a railway bridge that spans Karakaya Dam Lake between the cities of Malatya and Elazig in Turkey are presented. The bridge consists of 29 simply-supported steel trusses, each having a 64 m span length, giving a total bridge length of 2029.60 m. To understand the actual behaviour of the bridge, static and dynamic tests on the bridge spans were performed. The bridge was instrumented with strain-gauges mounted on the surface of the bridge members, accelerometers placed on the piers, abutments, and truss members and an optical laser based displacement sensor located at mid-span. Then, a three-dimensional finite element model of the bridge was generated using commercially available finite element analysis software using frame elements, a thick shell, and spring and rigid bar elements. The initial numerical model was calibrated using an optimization procedure based on automatically adjusting the spring constants and rigid bar rigidities with the help of MATLAB. Finally, the validity of the calibrated FE model was examined by the vertical displacement measurements.
Microstructure and Unsaturated Geotechnical Properties of Net-like Red Soils in Xuancheng, China
Authors: Wang Mingwu , Xu Peng , Li Jian , Qin Shuai 
Published: October 2014

Abstract
This study aimed at proper characterization of the microstructure and unsaturated properties of undisturbed red soil with white net-like veins from the Chenshan laterite section in Xuancheng City, China. The chemical composition and micromorphology of the white veins and red matrix were studied using a scanning electron microscope, an energy dispersive spectrometer, and digital image processing. Then a series of soil–water characteristic curves (SWCCs) and shear strength experiments were performed on undisturbed net-like red soils using triaxial stress path testing, and empirical expressions commonly adopted for geotechnical engineering applications were used to represent measured SWCCs. A detailed comparison of microstructures in undisturbed soils and on failure planes was undertaken. The results showed that the white veins and red matrix clearly appeared as distinct features at both macro and micro levels. More quartz amassed in the white vein, and more intense depletion of Fe oxide occurred in the red matrix. Measured SWCCs at drying and wetting behaved with hydraulic hysteresis. Change in the axial strain did not match that in the volumetric strain. The stress-strain curve obtained from the unsaturated triaxial shearing test showed the characteristic of strain softening; the peak deviator stress increased with increments of the confining pressure and suction. Pores less than 5 μm2 in size were much more common on the shear failure plane than in the undisturbed soil, whereas pores larger than 50 μm2 were fewer. The major axial angle of soil pores showed a dominant orientation after shearing. In addition, the roundness and fractal dimension of pore outlines on the shear failure plane were greater than those in the undisturbed soil. These results reveal that microstructure and suction play important roles in the unsaturated mechanical behaviors of net-like red soil.
Calculation of the Maximum Bending Strain: Machine and Specimen Components and Their Orientation Angles With “Vector Method”
Authors: Yifei Gao , Xinbang Liang , Lei Bao 
Published: October 2014

Abstract
“Vector method” was used in the calculation of the maximum bending strain (machine and specimen components) for circular and rectangular cross-section specimens under axial loading and bending. This method satisfactorily solved the orientation angle calculation problem for rectangular cross-section specimens (including thick and thin rectangular cross-section) caused by the testing machine component and the specimen component under the maximum bending strain, which is not solved in the ASTM E1012-12 and ISO 23788.
Hybrid Model for Evaluating Services in New Service Development
Authors: Yeh Ching-Chiang 
Published: October 2014

Abstract
The successful introduction and acceleration of new service development is important for obtaining a competitive advantage in many countries. However, selecting the right service to be adopted and developed is a challenging task. The aim of this study is to build a service evaluation model to evaluate various nationally available services for new service development based on a hybrid model. First, the interpretive structural modeling method is used to deal with the interrelationships among various criteria and sub-criteria. Then, the analytic network process method is employed to evaluate the weights and find the most appropriate service for development. To demonstrate the validity of the proposed method, Taiwan's service industry is used as an illustrative case. The results show that the model can be applied to decision making regarding the evaluation and selection of an available service for new service development (NSD), which may be helpful for service policy decision makers.
Characteristic Point of the Relatively Quiet Period for Limestone Failure Under Uniaxial Compression
Authors: Wang Chun-Lai , Lu Hui , Wang Fu-Li , Zuo Jian-Ping , An Ze-Yang , Bao Tian-Cai , Liu Lu , Lu Zhi-Jiang , Li Wei-Qiang , Luo Ming 
Published: October 2014

Abstract
In view of the precursory characteristic point of limestone failure under uniaxial compression, the underlying mechanisms are not sufficiently clear. Experimental studies examining the acoustic emission (AE) characteristics of the complete limestone failure process have been carried out under uniaxial compression. The experimental results, including accumulative AE counts, the curve of stress and strain, AE rate and stress-time, AE energy rate and stress-time, AE amplitude-time, and AE frequency- time were obtained in detail. The experimental results clearly indicate that AE activities of the samples were generated during the entire process of uniaxial compression. However, the abnormal AE activities appeared in the late stage of the unstable crack propagation phase. These parameters, such as the AE rate, AE energy rate, AE amplitudes, and AE frequencies, were observed to decrease sharply after a relatively quiet period. However, the accumulative AE counts remained at nearly constant values. Stress passed through the quiet period quickly before the peak stress, where the AE activities were enhanced. The AE rate increased suddenly and AE energy rate rose rapidly when the stress reached the peak stress of the samples. As a consequence, the relatively quiet period could be used as the precursory information of rock failure, and the starting point of a relatively quiet period could be predicted as a precursory characteristic point of rock failure. The start point of the relatively quiet period was approximately located in the range of 88 to 98 % of the peak stress.
Radial Strain Behaviors and Stress State Interpretation of Soil Under Direct Simple Shear
Authors: Kang Xin , Cheng Yao , Ge Louis 
Published: October 2014

Abstract
Radial strain behaviors and stress state interpretation methods of silica sand consolidated at different K0 values under modified direct simple shear were investigated in this research. Consolidated drained triaxial compression test, direct shear box test, and wire reinforced direct simple shear tests were conducted and the test results were compared and linked with the modified direct simple shear tests. Based on the observed testing data, simple shear specimens with constant lateral stress exhibited relative small radial strain during shear, especially under small shear strains. After the peak shear resistance has mobilized, radial strain increased rigorously until the specimen failed. Confining pressure and K0 values were found to have great deal of influence on the simple shear radial change. Two different methods were adopted to interpret the stress conditions within the simple shear specimen and the “pure shear” method was found more appropriate in interpreting the stress state in the modified direct simple shear test.
Characterization of Dense-Graded Asphalt With the Cantabro Test
Authors: Doyle Jesse D. , Howard Isaac L. 
Published: October 2014

Abstract
Durability of dense-graded asphalt (DGA) is a key issue with regards to long term pavement performance. There is a need for a practical and implementable test to estimate these parameters. Previous research has suggested that the Cantabro abrasion loss test has potential for this application. Both the development of the Cantabro method and its conventional application to open-graded friction course (OGFC) mixtures are reviewed. A four component research approach was undertaken to evaluate suitability of the Cantabro test for DGA mixtures that included testing of 438 specimens from 69 different mixtures. First, sensitivity of the test was assessed using a large range of typical Mississippi DGA mixtures. Second, variability of the test was measured by evaluating data sets with thirty replicates. Third, the effects of oven conditioning protocols were measured. Fourth, the effects of varying reclaimed asphalt pavement (RAP) contents were measured for warm-mix asphalt (WMA). The overall recommendation from the research was that the Cantabro test be given serious consideration for use as a durability measurement tool for DGA mixtures.
Standardization of Oil Sorbent Performance Testing
Authors: Bazargan Alireza , Tan Jun , McKay Gordon 
Published: October 2014

Abstract
Millions of barrels of petroleum and its products are transported across the globe every day. The hazard of oil spills is a looming threat that can lead not only to the loss of valuable products, but also seriously damage the environment and ecosystems. There are various ways of combating oil spills one of which is the use of sorbents. The ASTM F716-09 and ASTM F726-12 standards have been developed for absorbent/adsorbent performance and uptake capacity testing. However, most researchers do not use the procedures proposed by the ASTM when reporting their findings. Currently, the majority of the manuscripts published on oil sorbent testing do not use any uniform standard. Herein, we argue that the ASTM standards have some shortcomings that make them unattractive for researchers to use. These problems are discussed and possible solutions are proposed for more homogeneous and accurate reporting of results.