bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Multidirectional p-y Curves for Soft Clays
Authors: Mayoral JM , Pestana JM , Seed RB 
Published: March 2005

Abstract
The evaluation of performance of soil-pile-structure systems under seismic loading is one of the most complex problems in earthquake engineering. In the most common methodology, force-displacement curves are used to describe the nonlinear response of discrete soil springs connecting the piles to the “free-field” soil column using the concept of beam on nonlinear Winkler foundation. Although there is a great interest and on-going research to characterize the multi-directional “free-field” soil response, there is a lack of information and experimental data to formulate p-y curves in multi-directional loading conditions. A new testing device was designed and constructed to obtain high quality data to calibrate numerical tools used to evaluate the seismic performance of structures supported on deep foundations in soft clay. A suite of different ground displacement path scenarios observed during recent earthquakes was simulated to assess the effect of displacement history on measured p-y response.
Utilization of Quarry Dust to Improve the Geotechnical Properties of Soils in Highway Construction
Authors: Soosan TG , Sridharan A , Jose BT , Abraham BM 
Published: March 2005

Abstract
Quarries and aggregate crushers are basic requisites for construction industry and quarry dust is a byproduct of rubble crusher units. Geotechnical and mineralogical characterization of quarry dust and its interaction behavior with soils can lead to viable solutions for its large-scale utilization and disposal. The effect of addition of quarry dust on properties of red earth and two different cohesive soils; viz. kaolinite, Cochin marine clay was studied in detail. The results indicate that compaction characteristics and CBR of soils are improved by addition of quarry dust. Problems associated with the construction of highways over clayey subgrade can be reduced significantly by mixing with quarry dust.
Development of a New Hollow Cylinder Triaxial Apparatus for the Study of Expansion Tests in Clay
Authors: Silvestri V , Diab R , Ducharme A 
Published: March 2005

Abstract
This paper presents the use of a new, automated, Hollow Cylinder Triaxial cell (HCTA) for the study of expansion tests in saturated clay. The hollow cylinder cell was developed by modifying a hydraulic triaxial cell, and was adapted to perform cylindrical cavity expansion tests in annular soil specimens, with measurement of excess pore water pressures generated at various radial distances. The apparatus allows one to perform drained and undrained expansion tests, under plane strain or constant axial stress, with the expansion process being either stress-controlled or strain-controlled. The equipment, testing procedures, and analysis of typical undrained expansion tests are discussed.
Sealed Double-Ring Infiltrometers for Estimating Very Low Hydraulic Conductivities
Authors: Neupane D , Bowders JJ , Loehr JE , Bouazza A , Trautwein SJ 
Published: March 2005

Abstract
Sealed, Double-Ring Infiltrometers (SDRIs) are one of the preferred devices to measure infiltration rates of soil liners in the field. Existing SDRIs are well suited for measuring infiltration rates on materials with hydraulic conductivities on the order of 1 × 10−9 m/s. A very low hydraulic conductivity material (&lt;1 × 10−10 m/s), such as low-k asphalt concrete, requires some modifications to the existing SDRI designs. A Constant Head Board (CHB) was designed and employed to replace the commonly used flexible bag to accomplish measurement of very small flow increments. Flow increments as low as 0.05 mL can be effectively measured with this technique enabling field hydraulic conductivities as low as 1 × 10−11 m/s and possibly lower to be estimated in a matter of a day or two. The CHB is reliable, follows existing methods, and can account for the effects of temperature and barometric pressure changes on the flow rate.
Vibratory Plate Loading of Compacted and Instrumented Field Soil Beds
Authors: Mooney MA , Bouton CO 
Published: March 2005

Abstract
Field scale studies of foundation and plate vibrations, particularly in the nonlinear domain, are vital to improving understanding and validating analytical and numerical efforts. This paper describes the development of an experimental program to investigate the dynamic signature of a rigid plate and of the soil during surface plate vibration of compacted soil beds. Nineteen testing sequences were performed on 1.2-m deep prepared soil test beds embedded with miniature triaxial accelerometers. Various vibratory loading frequencies (10–60 Hz) and amplitudes (up to 220 kPa contact stress) were applied via a 0.45-m-diameter plate to the prepared test beds. The paper describes the load testing frame, the preparation of free field partially-saturated sand test beds, and the placement of triaxial accelerometers within the soil. Plate and soil acceleration profiles are presented for the range of applied forcing frequency and amplitude levels involved. The nonlinear soil-compactor system response is analyzed and presented in both the time and frequency domains to present key features observed during testing.
Determination of Surface and Thickness Characteristics of Textured Geomembranes Using Image Analysis
Authors: Yesiller N , Cekic A 
Published: March 2005

Abstract
Image analysis was used to determine surface topography and thickness of textured geomembranes. Images of cross sections (specimen length × thickness) of geomembranes were obtained at 50× magnification using a digital optical microscope. Thickness was determined as the distance between the top and bottom surfaces along an entire cross section. For surface analysis, profiles of top and bottom surfaces were extracted from the cross section images. Amplitude, spatial, hybrid, and functional texture parameters were determined. Tests were conducted on eleven samples of HDPE and LLDPE geomembranes manufactured by co-extrusion and embossing at varying thicknesses. The geomembranes were classified into three texture categories: high, medium, and low. Anisotropy and directionality were observed for all samples to varying degrees between and within manufacturing directions, respectively. Statistical analysis of the results indicated that surface topography of geomembranes could be determined by analyzing one surface of five specimens with 50 mm length. Comparisons were made between image analysis and mechanical tests for core thickness and asperity height. Image analysis and mechanical measurements were significantly different. Recommendations were made for the redesign of the mechanical devices by sizing the components in relation to the size and spacing of geomembrane texture features.
A Simple Method for Air Volume Change Measurement in Triaxial Tests
Authors: Laudahn A , Sosna K , Boháč J 
Published: March 2005

Abstract
The paper presents a simple and inexpensive device to measure the volume change of the pore-air of dry soil specimens in the drained triaxial tests under atmospheric conditions. The principle of the method was described by Bishop and Henkel (Bishop and Henkel 1962). The modified apparatus makes use of low-cost photoelectric sensors and computer control. The applicability of the method is demonstrated by a comparison with test data from conventional triaxial tests on water saturated specimens.
Small-Scale Modeling of Metal-Plate-Connected Wood Truss Joints
Authors: Gupta R , Miller TH , Kittel MR 
Published: March 2005

Abstract
The objective of this research was to develop 1/3-scale models of full-size (prototype) metal-plate-connected wood truss joints and a complete truss using similitude theory. To verify material properties, we compared moduli of elasticity of prototype and 1/3-scale model boards. Although the variation in stiffness of the model was greater than that of the prototype, the average properties of the model and prototype were similar. The resulting average design stiffness of 1/3-scale tension splice joints was within 1 % of the prototype joint stiffness, while the ultimate load was 7 % lower than the prototype. Stiffness and strength of model heel joints were within 22 % and 17 %, respectively, of the stiffness and strength of their prototypes. Finally, ten complete model trusses were fabricated and tested; their average stiffness and strength were 780 N/mm and 17.3 kN, respectively, after scaling up by similitude. Modeling full-size truss connection behavior up to the design load, and possibly to failure, with small-scale models and similitude theory may be feasible.
Estimation of the Uncertainty of Fe in Metallic Silicon Determined by Inductively Coupled Plasmas-Atomic Emission Spectroscopy
Authors: Wang DW , Wang SW , Zhao SQ 
Published: March 2005

Abstract
This practice provides information for combining standard uncertainties of Fe in metallic silicon determined by the ICP-AES method of the China Inspection and Quarantine (CIQ). The measurand Fe% is determined from other quantities p.q.r. . . through a functional relationship of the model f: Fe% = f(p.q.r . . .). The estimated standard deviation associated with the output estimate Fe%, called combined standard uncertainty and denoted by uc (Fe%), is determined from the estimated standard deviation associated with each larger input estimate (p.q.r . . .). The combined variance u2c (Fe%) can be viewed, by the sensitivity coefficients, as a sum of terms with the minor errors omitted.
Evaluation of Alternative Erosion Test Methods
Authors: Meged Y 
Published: March 2005

Abstract
The resistance of materials to liquid impingement erosion and to cavitation erosion are considered related properties. Hence, test methods dealing with these erosion mechanisms that are covered by ASTM standards are considered as alternative tests for some applications.These methods consist of vibratory cavitation erosion, cavitating liquid jet erosion, and liquid impingement erosion.
Meaningful comparison between test results obtained by these test methods depends on a high degree of repeatability and reproducibility within each test method. These prerequisites are not met in the prevailing standards, hence it is very difficult to convert test results between them.
Increasing repeatability and reproducibility within each test method are possible. This requires the preparation of the unified specimens in a controlled way, and the application of relevant comparison criteria.
Theoretical Derivation and Experimental Examination of the Stromeyer Relation for the Analysis of Fatigue Data
Authors: Graefe W 
Published: March 2005

Abstract
In 1914 Stromeyer published the empirical relation ±Sn =Fl + C(106/n)1/4 for the mathematical description of fatigue (±Sn -nominal fatigue stress; Fl - fatigue limit; C - constant; n - number of stress cycles). In a previous publication Graefe has given a theoretical explanation of such a relation. In this paper the statistical distribution of the experimental fatigue data for steel is tested and no deviation from a normal distribution is found. The frequency dependence of the fatigue data is analyzed and is explained by temperature variations due to internal friction.
Different models for defect growth are in concordance with the above-mentioned formulas.
Influence of Two Hexavalent Chromium-Free Coating types on Mechanical Behavior of Bolted Joints
Authors: Nascimento H , Santos SC , Sales WF , Palma ES 
Published: March 2005

Abstract
The goal of this work is to evaluate the performance of two different coating technologies for bolts. They are based on zinc and aluminum with no hexavalent chromium in their composition. These technologies were implemented because international laws for environmental and human health protection are limiting the use of the hexavalent form of chromium because it causes different cancer types in workers, mainly in recycling processes. The experimental tests were performed using M12x1.25–10.9 bolts that were submitted to the test of torsion-tension. The clamping load, total torque, torque on thread, torque on the bolt head, and twist angle were measured. The friction coefficients between the nut and bolt threads, between the face of the nut and its bearing surface, the global coefficients of friction, and the nut factor were also measured and analyzed.
The Functional Requirements for Water Resistive Barriers Exposed to Incidental Water Leakage, Part 2: Testing Materials
Authors: Bomberg M , Pazera M , Onysko D 
Published: March 2005

Abstract
The first part of this paper presented classification of Water Resistive Barrier (WRB) products.4 The main purpose of the research reported in this part is not to determine how different WRB products perform under exposure in real assemblies but to evaluate the effectiveness of the existing test methods to characterize moisture performance of WRB products. An additional purpose is to assess what properties should be determined to enable characterization of WRB for use in computer models for heat, air, and moisture (HAM) transport.
The investigation determined that the existing test methods do not provide adequate information. Therefore, new methods are proposed with a view to providing a better basis for evaluating WRB performance in wall assemblies.
A Model for Mixed-Mode Fatigue
Authors: Tamilselvan T , Lo KW , Gong YB , Zhao MM 
Published: March 2005

Abstract
The initial use of fracture mechanics to characterize crack growth by fatigue was by Paris. Since then, the application of fracture mechanics to fatigue problems has become routine. In the case of fatigue under mode I loading, the method of analysis, under conditions of constant amplitude and small-scale yielding, is well established. However, apart from the conditions of variable amplitude loading, large scale yielding, and short existing cracks, the procedures for analyzing fatigue under mode II and mixed-mode loading still have not been resolved. A general model, applicable to pure and mixed-mode fatigue crack growth, has been developed based on the unified model. The formulation of the general model is in terms of a power law relationship that is an extension of Paris. The experimental procedures for the measurement of mode II and mixed-mode fatigue crack growth, and verification of the proposed fatigue model, are dealt with herein. The verification has been confined to conditions of constant amplitude and small-scale yielding.
Numerical Investigation of Joint Effect on Shock Wave Propagation in Jointed Rock Masses
Authors: Jiao YY , Fan SC , Zhao J 
Published: March 2005

Abstract
To investigate the joint effect on shock wave propagation and attenuation in jointed rock masses, a small-scale field explosion test is analyzed numerically by using the three-dimensional discrete element method (3D DEM) and the three-dimensional finite difference method (3D FDM). Results show that rock joints act as a kind of filter through which only low frequency shock waves are allowed to pass. This indicates that high frequency shock waves do no harm to far-field structures when they have to travel across joint sets with specific spacing. Results also reveal that the orientation of the joint sets can remarkably affect the amplitude and frequency composition of shock waves. Furthermore, as a discontinuous numerical method, 3D DEM can capture the main features of shock waves, and most importantly, it can simulate the 3D effect of rock joints. It can be concluded that in modelling 3D shock wave propagation and attenuation in jointed rock masses, 3D DEM has unique advantages over 2D modeling, 3D FDM, and even field testing.
Experimental Designs for Reliable Detection of Linkage Disequilibrium in Unstructured Random Population Association Studies
Authors: Ball Roderick D 
Published: March 2005

AbstractA method is given for design of experiments to detect associations (linkage disequilibrium) in a random population between a marker and a quantitative trait locus (QTL), or gene, with a given strength of evidence, as defined by the Bayes factor. Using a version of the Bayes factor that can be linked to the value of an F-statistic with an existing deterministic power calculation makes it possible to rapidly evaluate a comprehensive range of scenarios, demonstrating the feasibility, or otherwise, of detecting genes of small effect. The Bayes factor is advocated for use in determining optimal strategies for selecting candidate genes for further testing or applications. The prospects for fine-scale mapping of QTL are reevaluated in this framework. We show that large sample sizes are needed to detect small-effect genes with a respectable-sized Bayes factor, and to have good power to detect a QTL allele at low frequency it is necessary to have a marker with similar allele frequency near the gene.
The Origin of Subfunctions and Modular Gene Regulation
Authors: Force Allan , Cresko William A , Pickett F Bryan , Proulx Steven R , Amemiya Chris , Lynch Michael 
Published: March 2005

Abstract
Evolutionary explanations for the origin of modularity in genetic and developmental pathways generally assume that modularity confers a selective advantage. However, our results suggest that even in the absence of any direct selective advantage, genotypic modularity may increase through the formation of new subfunctions under near-neutral processes. Two subfunctions may be formed from a single ancestral subfunction by the process of fission. Subfunction fission occurs when multiple functions under unified genetic control become subdivided into more restricted functions under independent genetic control. Provided that population size is sufficiently small, random genetic drift and mutation can conspire to produce changes in the number of subfunctions in the genome of a species without necessarily altering the phenotype. Extensive genotypic modularity may then accrue in a near-neutral fashion in permissive population-genetic environments, potentially opening novel pathways to morphological evolution. Many aspects of gene complexity in multicellular eukaryotes may have arisen passively as population size reductions accompanied increases in organism size, with the adaptive exploitation of such complexity occurring secondarily.
Mutations of a Redundant α-Tubulin Gene Affect Caenorhabditis elegans Early Embryonic Cleavage via MEI-1/Katanin-Dependent and -Independent Pathways
Authors: Lu Chenggang , Mains Paul E 
Published: March 2005

Abstract
The C. elegans zygote supports both meiosis and mitosis within a common cytoplasm. The meiotic spindle is small and is located anteriorly, whereas the first mitotic spindle fills the zygote. The C. elegans microtubule-severing complex, katanin, is encoded by the mei-1 and mei-2 genes and is solely required for oocyte meiotic spindle formation; ectopic mitotic katanin activity disrupts mitotic spindles. Here we characterize two mutations that rescue the lethality caused by ectopic MEI-1/MEI-2. Both mutations are gain-of-function alleles of tba-2 α-tubulin. These tba-2 alleles do not prevent MEI-1/MEI-2 microtubule localization but do interfere with its activity. TBA-1 and TBA-2 are redundant for viability, but when katanin activity is limiting, TBA-2 is preferred over TBA-1 by katanin. This is similar to what we previously reported for the β-tubulins. Removing both preferred α- and β-isoforms results in normal development, suggesting that the katanin isoform preferences are not absolute. We conclude that while the C. elegans embryo expresses redundant α- and β-tubulin isoforms, they nevertheless have subtle functional specializations. Finally, we identified a dominant tba-2 allele that disrupts both meiotic and mitotic spindle formation independently of MEI-1/MEI-2 activity. Genetic studies suggest that this tba-2 mutation has a “poisonous” effect on microtubule function.
Using Pool Noodles to Teach Mitosis and Meiosis
Authors: Locke John , McDermid Heather E 
Published: March 2005

Abstract
Although mitosis and meiosis are fundamental to understanding genetics, students often find them difficult to learn. We suggest using common “pool noodles” as teaching aids to represent chromatids in classroom demonstrations. Students use these noodles to demonstrate the processes of synapsis, segregation, and recombination. Student feedback has been overwhelmingly positive.
The Ku Protein Complex Is Involved in Length Regulation of Drosophila Telomeres
Authors: Melnikova Larisa , Biessmann Harald , Georgiev Pavel 
Published: March 2005

Abstract
Chromosome ends in Drosophila melanogaster can be elongated either by terminal attachment of the telomere-specific retrotransposons HeT-A and TART or by terminal gene conversion. Here we show that a decrease in Ku70 or Ku80 gene dosage causes a sharp increase in the frequency of HeT-A and TART attachments to a broken chromosome end and in terminal DNA elongation by gene conversion. Loss of Ku80 has more pronounced effects than loss of Ku70. However, lower Ku70 concentration reduces the stability of terminally deficient chromosomes. Our results suggest a role of the end-binding Ku complex in the accessibility and length regulation of Drosophila telomeres.
Natural Allelic Variation in the Temperature-Compensation Mechanisms of the Arabidopsis thaliana Circadian ClockSequence data from this article have been deposited with the EMBL/GenBank Data Libraries under accession nos. AY685131 and AY685132.
Authors: Edwards Kieron D , Lynn James R , Gyula Péter , Nagy Ferenc , Millar Andrew J 
Published: March 2005

Abstract
Temperature compensation is a defining feature of circadian oscillators, yet no components contributing to the phenomenon have been identified in plants. We tested 27 accessions of Arabidopsis thaliana for circadian leaf movement at a range of constant temperatures. The accessions showed varying patterns of temperature compensation, but no clear associations to the geographic origin of the accessions could be made. Quantitative trait loci (QTL) were mapped for period and amplitude of leaf movement in the Columbia by Landsberg erecta (CoL) and Cape Verde Islands by Landsberg erecta (CvL) recombinant inbred lines (RILs) at 12°, 22°, and 27°. Six CvL and three CoL QTL were located for circadian period. All of the period QTL were temperature specific, suggesting that they may be involved in temperature compensation. The flowering-time gene GIGANTEA and F-box protein ZEITLUPE were identified as strong candidates for two of the QTL on the basis of mapping in near isogenic lines (NILs) and sequence comparison. The identity of these and other candidates suggests that temperature compensation is not wholly determined by the intrinsic properties of the central clock proteins in Arabidopsis, but rather by other genes that act in trans to alter the regulation of these core proteins.