bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liquid-Metal Embrittlement of 7075 Aluminum and 4340 Steel Compact Tension Specimens by Gallium
Authors: Kolman DG , Chavarria R 
Published: February 2009

Abstract
Liquid-metal embrittlement of aluminum alloy 7075-T6 and AISI 4340 steel by gallium has been observed previously. Unfortunately, quantitative data regarding the level of embrittlement are limited due to the difficulty of testing fracture mechanics specimens. This study uses L-T compact tension specimens to determine the threshold stress intensity for crack initiation during exposure to gallium. Sample surfaces were wet with gallium prior to exposure at 35°C by removing the crack tip and side groove oxide film with a scalpel in the presence of gallium. Both 4340 steel and 7075 Al were embrittled by Ga as measured by threshold stress intensity. Kthi, the stress intensity at crack initiation as detected by direct current potential drop (DCPD), for 4340 and 7075 was 33% and 5% of KIci (the fracture toughness as detected by DCPD), respectively. In contrast to air-exposed samples, extremely rapid crack propagation to failure of Ga-exposed samples was observed. Fractography revealed intergranular fracture of Al 7075 and 4340 steel following Ga exposure.
A Procedure for Extended Extrapolation of Creep Rupture Data
Authors: Sandström R 
Published: February 2009

Abstract
To be able to perform extended extrapolation of creep rupture data, i.e., extrapolation by more than a factor of three in time, a new procedure is proposed. A free temperature model for the time-temperature parameter is used that provides a high degree of flexibility. Postassessment tests are formulated to verify that the chosen time-temperature parameter has sufficient stability. In the analysis, criteria are introduced for the position of the predicted creep rupture curve in relation to the scatter band of data as well as criteria on derivatives of the predicted creep rupture curves. The procedure has been applied successfully to five common creep-resistant pressure vessel steels: one low-alloy steel (2Cr 1Mo) and four austenitic stainless steels: 304H, 316, 253MA, and 800H. The small deviations between the full datasets and strongly culled sets demonstrate the validity of the proposed procedure.
A Comparison of Results on Helmet Impact Testing
Authors: Ingmar Johnson G 
Published: February 2009

Abstract
Drop impact testing of head protection helmets has been based on different methods in the European Committee for Standardization (CEN) and International Organization for Standardization (ISO) standards. Since it would be desirable to unite these two into one international standard, work was initiated to find out whether the corresponding test methods could be considered equivalent and interchangeable for helmet certification.
The Reliability and Self-Diagnosis of Sensors in a Multisensor Data Fusion Diagnostic System
Authors: Wang J , Wang H 
Published: February 2009

Abstract
Any error in a data fusion system that is used to diagnose and detect machine faults, especially an error in sensor measurement information, will result in an incorrect diagnostic conclusion. The accuracy and reliability of sensor measurement is a prerequisite for reducing the uncertainty of the fusion system and accurately diagnosing system faults. The measurement error of the multisensor and the degree of reliability of the detecting system can be determined by a multisensor consistency check. In this paper, we use the “probability distance measure” to determine the compatibility of multisensor information and to ensure that the measurements represent the same target (or state). We show our experimental results, which demonstrate a good result.
Fault Diagnosis of Loaded Water Hydraulic Actuators by Online Testing with LabVIEW®
Authors: He Y , Chua PSK , Lim GH , Tan ACH 
Published: February 2009

Abstract
In recent years, with the development of technology in materials and machining, it is becoming possible to produce modern water hydraulic components that are made of lubricant-free and anticorrosive materials and to achieve very close tolerances to reduce internal leakage due to the low viscosity of water. As water is nontoxic, environmentally friendly, and readily available, many industries are already turning to modern water hydraulic systems to replace their oil hydraulic counterparts. As with all systems, the increasing use of water hydraulic systems by more industries will result in a greater need to monitor and maintain the systems. This paper is concerned with online testing and fault diagnosis of loaded modern water hydraulic cylinders and axial piston motors. LabVIEW® (Laboratory Virtual Instrument Engineering Workbench) data acquisition hardware and development software were used for data acquisition and processing. Likely real-life faults were simulated on the hydraulic actuators' internal components. The actuators also were operated to capture their unique vibration signals in their faulty states and the results compared with reference signatures of the same actuators when they were in their new or healthy states. The vibration signatures and amplitude spectra, average extension/retraction duration, and flow trending amplitude of the water hydraulic actuators versus piston seal wear, rod seal wear, piston shoe wear, and capstan surface wear under different operating conditions of simulated loads and speeds are presented and discussed. The results show that there is a distinctive variation in vibration signals, flow rate, and average stroking duration with increase in loads for both actuators.
A Study on the Beginning of Secondary Compression of Soils
Authors: Robinson RG 
Published: February 2009

AbstractThe time-compression curve obtained from a laboratory one-dimensional consolidation test generally consists of three parts, namely initial compression, primary consolidation, and secondary compression. While the initial compression occurs immediately after the application of a load increment, the primary consolidation and the secondary compression are time-dependent. It is not known whether both primary consolidation and secondary compression occur concurrently or if the secondary compression begins after the end of primary consolidation, as assumed in general practice. This paper examines this aspect based on the pore water pressure measured at the base of the sample during consolidation. It was observed that the beginning of secondary compression strongly depends on the load increment ratio (LIR). For the inorganic soils tested, the secondary compression begins practically after the end of primary consolidation. When a small LIR of 0.2 is adopted, the secondary compression starts as early as about 55 % of the primary consolidation is over. For the organic soil tested, the secondary compression begins much earlier, compared to the inorganic soils even at a higher load increment ratio. The secondary compression-time relationship can be well represented by a hyperbolic model. The method adopted in this article is capable of separating the primary consolidation and secondary compression from time-compression data once the pore water pressure at the base of the sample is known.
Review and Evaluation of Medical Image Segmentation Using Methods of Optimal Filtering
Authors: Trichili H , Bouhlel MS , Kammoun F 
Published: February 2009

Abstract
Image segmentation is an important process of image analysis. It consists of subdividing an image into its constituent parts and extracting these interesting parts. A large variety of segmentation algorithms have been developed. The evaluation and comparison of these algorithms turns out to be important and even indispensable for correctly using them. This paper presents an objective study of segmentation algorithms using the methods of optimal filtering. This study is distinguished from other studies by its consideration of both evaluation and comparison, treating both image cases (noisy and non-noisy ones). The results of implementation, an evaluation of the advantages and the drawbacks of each one of them, and a study of their immunity towards three types of noise are also presented. All these characteristics make this study a general and effective one for revealing the performance of segmentation algorithms using the methods of optimal filtering.
Influence of the Geometry of the Extrusion Die on the Melt Strength of Polymers
Authors: Baldi F , Rösch D 
Published: February 2009

Abstract
In the past some studies have been carried out to investigate the melt strength of polymers with the purpose of comparing the results obtained with different materials and at different temperatures. In those experimental activities, once that the testing instrument had been chosen, the polymers were considered the object of the investigation and the attention was rarely focused on the testing geometry. The present work, instead, intends to analyze the influence that the geometry of the extrusion die has on the melt strength of polymers. In particular, attention is focused on the analysis of the differences produced on the melt strength of a material, when the extruded filament is subjected, via the use of two different dies specifically designed, to two distinct temperature profiles along the stretching axis. This investigation highlights that the testing geometry chosen for an experimental activity based on melt tension tests, via haul-off measurements, plays a fundamental role in the correct interpretation of the results. In fact it is demonstrated that the correct choice of the extrusion die allows one to obtain results much more similar to the real processing type that, using melt tension tests, has to be analyzed.
Testing of Bridge Weigh-In-Motion System in a Sub-Arctic Climate
Authors: McNulty P , O'Brien EJ 
Published: February 2009

Abstract
Systems for weighing vehicles while they are in motion are in widespread use in many countries. The accuracy of these weigh-in-motion (WIM) systems is strongly influenced by the road profile and vehicle dynamics. Systems based on sensors that are embedded in the pavement or placed on top of the road surface can measure the axle load only for the fraction of a second for which the wheels are present on the sensor. An alternative to pavement WIM systems that increases the length of the load-sensitive element is to use an existing bridge as a weighing scale (Bridge WIM). A major test of a Bridge WIM system at a test site near the Arctic Circle is described in this paper. The test was conducted along-side a larger test of pavement WIM systems. A large number of trucks from random traffic were weighed statically and the results compared to those from the Bridge WIM system. The accuracy of the system is assessed in accordance with the COST 323 WIM specification, which provides a standardized method of accuracy classification. The Bridge WIM system is proven to perform satisfactorily and consistently for a wide range of temperatures in near-Arctic climatic conditions.
Investigation of Effects of Testing Methods on Characterization of Asphalt Concrete
Authors: Wen H 
Published: February 2009

Abstract
A variety of testing methods are employed by researchers to characterize the fatigue performance of asphalt concrete. These testing methods need to be evaluated based on their performance to characterize the fundamental properties and field performance of mixtures. In this study, the indirect tensile tests and the uniaxial tests were investigated. The indirect tensile creep tests and the uniaxial tensile creep tests were performed on a North Carolina mix to study the characterization of the fundamental properties and on WesTrack mixes to study the characterization of field performance. It was found that that the values of creep compliance from the indirect tensile creep and the unaxial tensile creep tests on North Carolina mix cannot be compared favorably. Fracture energies from the indirect tensile strength tests on WesTrack mixes highly correlate with the field performances, while those from uniaxial direct tension tests did not match field performances. It is believed that anisotropicity could be the cause of differences in performance of the two test methods. It is disconcerting when researchers attempt to establish a constitutive relationship between the property parameters of mixtures and laboratory fatigue life using different testing methods, without knowing if the laboratory fatigue life from these testing methods really reflects field performance. Further research is needed to obtain a better understanding of different testing methods.
Overcoming Multicollinearity in Near Infrared Analysis for Lycopene Content Estimation in Tomatoes by Using Ridge Regression
Authors: Pasternak H , Schmilovitch Z , Fallik E , Edan Y 
Published: February 2009

Abstract
High intercorrelation between absorbance at different wavelengths is common in near infrared analysis and was observed in an experiment to determine lycopene in tomatoes. Simulation analysis and experiments were conducted to estimate the effects of this problem on the estimators and on the predictive ability of linear regression and ridge regression. Applying linear regression to the experimental data resulted in very large parameter values, implying poor predictive ability. When linear regression gives very large parameter values, the estimated parameters are practically random numbers and are not correlated to the true ones. Ridge regression yielded estimators with normal values, but which are still poorly correlated with the true parameters. However, the predictive ability of the derived equation is good and may be used in practice to determine lycopene content in tomatoes since it is relatively easy to update.
On Experimental J Estimation Equations Based on CMOD for SE(B) Specimens
Authors: Kim YJ , Schwalbe KH 
Published: February 2009

Abstract
This note addresses the accuracy of the J-estimation equation for shallow-cracked single edge cracked bars, SE(B), as originally proposed by Kirk and Dodds (1993), based on 2D finite element analysis. Our study placed particular emphasis on the sensitivity of the Kirk-Dodds equation to the nature of the material, including continuously-hardening materials and those exhibiting Lüders strain. It was found that the Kirk-Dodds equation provides acceptable results except for specimen bars with very deep cracks such as those with a/W = 0.7 or greater. Accordingly, based on slip line field analysis, a modification of the original equation is suggested, which when used provides consistent results for all crack lengths.
A New Method for Testing the Abrasive Properties of Paper and Other Sheet Materials
Authors: Srinivasan R , Puttaswamygowda G 
Published: February 2009

Abstract
Manufacturing operations such as die cutting and slitting of sheet materials result in wear of the tooling. A new method for measuring the abrasive properties of paper and other sheet materials is proposed. The method continuously monitors the force required for penetrating a sheet sample as multiple punches are made with a needle. Abrasive wear caused by the sheet sample changes the geometry of the needle, and consequently changes the penetration force. The trend of the force is used as a measure of the abrasivity of the sheet sample. Several sheet paper samples were tested using this method with two different needle geometries. In all cases, the magnitude of the force decreased with an increasing number of punches. The rate of change of force depends on the type of paper and the initial geometry of the needle.
Application of a Geotechnical Centrifuge for Estimation of Unsaturated Soil Hydraulic Conductivity
Authors: Singh DN , Kuriyan SJ , Madhuri V 
Published: February 2009

Abstract
Contamination of the groundwater regime and subsurface soils is one of the major problems that has arisen due to rapid industrialization. Spread of contaminants in the unsaturated soil strata, mainly close to the ground surface and lying above the water table, depends on the hydraulic conductivity of the soil. As such, estimation of unsaturated soil hydraulic conductivity becomes very important. However, it is quite difficult to estimate the same in a reasonable amount of time, due to the very low hydraulic conductivity of unsaturated soil. The potential of a geotechnical centrifuge for modeling various geoenvironmental engineering problems being very well established, an effort has been made to obtain the unsaturated state of a silty soil, starting from its saturated state, by centrifugation. The soil water characteristic curves obtained have been used for determining the unsaturated soil hydranlic conductivity.
Packaging Specifications for Corrugated Boxes with Heavy Flowable Products in Single Parcel Shipments
Authors: Singh SP , Burgess G , Pratheepthinthong S , Singh J 
Published: February 2009

Abstract
This study investigated the corrugated board specifications that are recommended in the Fibre Board Association Handbook as part of Item 222 of the National Motor Freight Classification for shipping flowable items such as nuts and bolts using the single parcel shipping environment (UPS, FedEx, USPS). The study found that the existing specifications are greatly insufficient to contain these types of products in this environment. The study recommends to double the requirements for bursting strength when such items need to be shipped in the single parcel environment and to limit the maximum package weight to 40 lb.
Microindentation Test for Charaterization of Plastic Properties of Laser Alloyed Layers
Authors: Kucharski S , Radziejewska J 
Published: February 2009

Abstract
In this paper a method of characterization of plastic material properties of the surface layers constituted by laser alloying is proposed. The applied characterization method is based on the analysis of load-penetration depth curves obtained in repeated loading-unloading-reloading microindentation tests. Spherical indenters were used. A Stellite™ alloyed layer and a tungsten carbide alloyed layer were considered. The results of metallographic analysis of the layers and their microstructure are presented. The method was also used for the characterization of plastic parameters for carbon steel. Its stress-strain curve generated by the characterization process is compared with that obtained in a tension test.
Methods for Fatigue Testing Off-Road Bicycle Handlebars Based on Assembly Effects Using Two Different Stem Designs
Authors: McKenna SP , Hill MR , Hull ML 
Published: February 2009

Abstract
Assembly of off-road bicycle handlebars with a stem that clamps the handlebar around its circumference would be expected to affect fatigue performance by introducing both assembly stresses and stress concentration. Because the effect of clamping on fatigue performance is unknown and because of the need to insure structural reliability in the stem-handlebar assembly to prevent serious injury, the objectives of the work reported by the present article were fourfold. One was to determine the stresses due to assembly and the stress concentration induced in a handlebar for two different clamp designs (i.e. 1-bolt and 2-bolt), a second was to determine experimentally the high cycle constant amplitude load fatigue lives of the two stem-handlebar assemblies, a third was to determine experimentally the variable amplitude load fatigue lives, and the fourth was to predict the variable amplitude load fatigue life with constant amplitude load fatigue test results. The handlebar was instrumented with strain gages and the assembly strains were measured when the stem clamps were tightened. The handlebar was also loaded as a cantilever beam while the applied strains were measured for each assembly. Stresses were computed and the maximum stresses induced by clamping exceeded 200 MPa for both assemblies. A method unique to this study was devised to determine the stress concentration at an arbitrary angular location around the circumference of the handlebar and for an arbitrary loading direction in the plane of the bicycle. For a load directed along an angle of -38° (clockwise rotation from horizontal viewed from the right), both stems created similar stress concentration; the location of maximum applied stress was shifted by 30° from the point that would be expected in the absence of assembly and the stress was increased by 40% at this location. The measured fatigue lifetimes for constant amplitude loading were similar for the two stem designs but the variable amplitude load fatigue lifetime for the 1-bolt stem assembly was shorter than that for the 2-bolt stem assembly by 19%. The fatigue lifetimes for variable amplitude loading based on constant amplitude load fatigue test results were predicted to within 3% and 33% for the 1-bolt and 2-bolt stems, respectively. Thus, constant amplitude load fatigue test results can be used to approximate the variable amplitude load fatigue life. However, the ranking of different assemblies may not be accurately indicated by constant amplitude load fatigue data.
Evaluation of a Boron-Nitrogen, Phosphate-Free Fire-Retardant Treatment. Part II. Testing of Small Clear Specimens per ASTM Standard D 5664-95, Methods A and B
Authors: Winandy JE , Herdman D 
Published: February 2009

Abstract
The objective of this work was to evaluate the effects of a new boron-nitrogen, phosphate-free fire-retardant (FR) formulation on several mechanical properties of FR-treated wood and to assess the potential of this treatment for in-service thermal-induced strength loss resulting from exposure to high temperature. Fire-retardant-treated and untreated small clear specimens were cut from three wood species, Douglas-fir, southern pine, and white spruce, according to ASTM D 5664-95 and evaluated in bending and tension, compression, and shear parallel to grain. Evaluations were conducted before and after matched specimens were exposed at elevated temperature (150°F(66°C)) for 36, 72, or 108 days. The results indicate that treatment with FR and redrying followed by long-term exposure at high temperature could significantly affect some mechanical properties when compared to the same properties of untreated and unexposed controls. However, FR treatment and redrying in themselves did not have an across-the-board effect on all properties of specimens or on the rate of strength loss compared to the properties of matched untreated lumber exposed at 150°F (66°C) for up to 108 days. Our analysis indicated that for some species, some engineering properties will require modification, whereas other species-property combinations will not. Our results indicate that the likelihood of FR-treated lumber to experience in-service reduction in mechanical properties when exposed to elevated temperatures is no different than that of matched untreated material.