bluuebunny/crossref_metadata_2025 huggingface dataset:
Data Integration Issues for a Farm Decision Support System
Authors: Jones Marion , Taylor George
Published: September 2004

This paper explores data integration and compatibility issues raised during the development of a prototype spatial decision support system (SDSS) as a support tool for the farm manager of the University of Central Lancashire's farm at Newton Rigg and as a teaching resource for staff and students on campus. Metadata concerns and interoperability problems are addressed in detail. The paper outlines the proposed model for the SDSS and issues identified during the investigation of the users’ requirements and the analysis of the underlying spatial data sets. The initial data issues relate to the identification of existing and missing data sets (Parker et al. 1996) and the creation of metadata describing the data sets. The second area to be explored concerns interoperability issues. This is relevant when users must access more than one dataset using distributed computing resources (Sondheim et al. 1999).
Spatial Differences in Multi‐Resolution Urban Automata Modeling
Authors: Dietzel Charles , Clarke Keith C
Published: September 2004

The last decade has seen a renaissance in spatial modeling. Increased computational power and the greater availability of spatial data have aided in the creation of new modeling techniques for studying and predicting the growth of cities and urban areas. Cellular automata is one modeling technique that has become widely used and cited in the literature; yet there are still some very basic questions that need to be answered with regards to the use of these models, specifically relating to the spatial resolution during calibration and how it can impact model forecasts. Using the SLEUTH urban growth model (Clarke et al. 1997), urban growth for San Joaquin County (CA) is projected using three different spatial grains, based on four calibration routines, and the spatial differences between the model outputs are examined. Model outputs show that calibration at finer scaled data results in different parameter sets, and forecasting of urban growth in areas that was not captured through the use of more coarse data.
The micro‐mechanics of single molecules studied with atomic force microscopy
Authors: Fisher Thomas E. , Marszalek Piotr E. , Oberhauser Andres F. , Carrion‐Vazquez Mariano , Fernandez Julio M.
Published: September 2004

The atomic force microscope (AFM) in its force‐measuring mode is capable of effecting displacements on an angstrom scale (10 Å= 1 nm) and measuring forces of a few piconewtons. Recent experiments have applied AFM techniques to study the mechanical properties of single biological polymers. These properties contribute to the function of many proteins exposed to mechanical strain, including components of the extracellular matrix (ECM). The force‐bearing proteins of the ECM typically contain multiple tandem repeats of independently folded domains, a common feature of proteins with structural and mechanical roles. Polysaccharide moieties of adhesion glycoproteins such as the selectins are also subject to strain. Force‐induced extension of both types of molecules with the AFM results in conformational changes that could contribute to their mechanical function. The force‐extension curve for amylose exhibits a transition in elasticity caused by the conversion of its glucopyranose rings from the chair to the boat conformation. Extension of multi‐domain proteins causes sequential unraveling of domains, resulting in a force‐extension curve displaying a saw tooth pattern of peaks. The engineering of multimeric proteins consisting of repeats of identical domains has allowed detailed analysis of the mechanical properties of single protein domains. Repetitive extension and relaxation has enabled direct measurement of rates of domain unfolding and refolding. The combination of site‐directed mutagenesis with AFM can be used to elucidate the amino acid sequences that determine mechanical stability. The AFM thus offers a novel way to explore the mechanical functions of proteins and will be a useful tool for studying the micro‐mechanics of exocytosis.
Stimulation of exocytosis without a calcium signal
Authors: Hille Bertil , Billiard Julia , Babcock Donner F. , Nguyen Toan , Koh Duk‐Su
Published: September 2004

More than 30 years ago, Douglas (Douglas & Rubin, 1961; Douglas, 1968) proposed that intracellular Ca2+ controls stimulus‐secretion coupling in endocrine cells, and Katz & Miledi (1967; Katz, 1969) proposed that intracellular Ca2+ ions control the rapid release of neurotransmitters from synapses. These related hypotheses have been amply confirmed in subsequent years and for students of excitable cells, they dominate our teaching and research. Calcium controls regulated exocytosis. On the other hand, many studies of epithelial and blood cell biology emphasize Ca2+‐independent regulation of secretion of mucin, exocytotic delivery of transporters and degranulation. The evidence seems good. Are these contrasting conclusions somehow mistaken, or are the dominant factors controlling exocytosis actually different in different cell types? In this essay, we try to reconcile these ideas and consider classes of questions to ask and hypotheses to test in seeking a more integrated understanding of excitation‐secretion coupling. Our review is conceptual and narrowly selective of a few examples rather than referring to a broader range of useful studies in the extensive literature. The examples are taken from mammals and are documented principally by citing other reviews and two of our own studies. The evidence shows that protein phosphorylation by kinases potentiates Ca2+‐dependent exocytosis and often suffices to induce exocytosis by itself. Apparently, protein phosphorylation is the physiological trigger in a significant number of examples of regulated exocytosis. We conclude that although sharing many common properties, secretory processes in different cells are specialized and distinct from each other.
The geochemical diversity of neogene clay deposits in Crete and its implications for provenance studies of Minoan pottery*
Authors: Hein A. , Day P. M. , Quinn P. S. , Kilikoglou V.
Published: September 2004

The determination of provenance probably forms the primary role of geochemical analyses in archaeological ceramic studies. In what has comprised a successful field of study, the ultimate basis for such research has been the comparison of pottery compositions with the geochemical diversity displayed by clay deposits within a given study area. Although such studies are now common, the understanding of chemical and mineralogical variability in ceramic raw materials has been somewhat neglected, with the dominance of assumptions rather than the actual analysis of clays. In this paper, a study is presented of Neogene clays in Crete (Greece), a clay type commonly used in ancient and modern pottery production. Sixty‐one samples were taken from 28 locations in the central and eastern parts of the island, to reveal both intra‐ and inter‐deposit variability.

In one deposit chosen for multiple sampling, the 14 samples display great variability in the alkali elements, Fe and Co, and to a lesser extent in the REEs. Many of the geographically separate deposits differ from each other in chemical composition, with Eastern Cretan deposits showing higher REE concentrations and higher Th/Sc ratios, whereas Central Cretan deposits of younger geological stages are characterized by a lower Th/U ratio. Mineralogical analysis by XRD is used to explain aspects of the geochemical variability of the clays.
Inductively coupled plasma emission spectroscopy and Postclassic Petén slipped pottery: an examination of pottery wares, social identity and trade*
Authors: Cecil L. G.
Published: September 2004

ICP–ES analysis of the clay pastes of Postclassic (c.
ad
850–1524) slipped pottery from the central Petén lakes region establishes chemical composition groups that provide information concerning manufacturing traditions and trading patterns. These data demonstrate that manufacturing traditions and trading patterns change throughout the Postclassic period, reflecting possible socio‐political alliances as different ethnic groups migrated to and from the Yucatán peninsula into the central Petén lakes region. The chemical composition groups also demonstrate that some manufacturing traditions imitate those from the Late Classic period and that some clay sources were used throughout the Postclassic period for multiple ceramic groups.
The production and technology of glazed ceramics from the middle ages, found in the saepinum territory (Italy): a multimethodic approach*
Authors: Comodi P. , Bernardi M. , Bentivoglio A. , Gatta G. D. , Zanazzi P. F.
Published: September 2004

A collection of ceramics from the Middle Ages found in Altilia and Terravecchia (the Saepinum area, Campobasso, Italy) were characterized by using different mineralogical analyses to investigate their provenance and production techniques. The body ceramic was investigated using Rietveld phase analysis of X‐ray powder diffraction patterns, X‐ray fluorescence spectrometry and scanning electron microscopy. The chemical compositions of the coatings were measured by scanning electron microscopy and their mineralogical compositions were determined using a particular technique of X‐ray small‐angle scattering (SAS) optimized for studies of thin films. Moreover, the material used for decoration was studied using micro‐Raman spectroscopy.

The archaeometric results confirmed the distinction into two different ceramic classes, already individuated from archaeological analysis: the Altilia objects belong to the protomajolica class, whereas the objects from Terravecchia are RMR (ramina‐manganese‐red) ceramics. A comparison between the chemical and mineralogical compositions of good‐quality ceramic objects and those of waste products indicated local production of the ceramics. A sharp distinction was found in the chemical composition of the coatings: the Altilia products have tin‐opacified lead glazes, while the Terravecchia ones have transparent high‐lead glazes. Among the Altilia products, the unsuccessful process that produced a large quantity of discarded materials was attributed to the high lead content of the glazes. In fact, the principal advantage of the high lead content was to make the preparation and application of the glaze suspension easier, but the risk of reduction of lead oxide to metallic lead was greatly increased.

Using micro‐Raman spectroscopy, the following minerals were identified as pigments: pyrolusite for the dark colour, malachite for green, lepidocrocite for yellow and hematite for red.
The production technology of Iznik pottery—a reassessment*
Authors: Paynter S. , Okyar F. , Wolf S. , Tite M. S.
Published: September 2004

Previous research has established that Iznik pottery differs from other Islamic stonepaste pottery in that its stonepaste bodies contain lead oxide as well as soda and lime, and that a significant proportion of the tin oxide in its glaze is present in solution rather than as tin oxide particles. In order to better understand these distinguishing features, the chemical compositions and microstructures of Iznik pottery and tile samples, together with those of lumps of glass found in association, were investigated using both scanning electron and optical microscopy. These data have been supplemented by the study of replicate lead–alkali glazes produced in the laboratory with a range of different compositions. The results demonstrate that separate soda–lime and high‐lead glasses were used in the production of Iznik stonepaste bodies, and that the total glass contents of the bodies were significantly higher than those quoted by Abū’l‐Qāsim, who was writing in about
ad
1300. The very high purity of the lead–soda Iznik glazes indicated that the alkali flux used was either a purified plant ash or an as yet unidentified mineral source of soda. Replication experiments established that the high solubility of tin oxide in the glaze was due to the high purity of the glaze constituents. Furthermore, it is suggested that tin oxide was added to the glaze in order to give it a very slight opacity and thus obscure any blemishes in the underlying body.
The early roman imperial AES coinage II: Tracing the copper sources by analysis of lead and copper isotopes—copper coins of Augustus and Tiberius*
Authors: Klein S. , Lahaye Y. , Brey G. P. , Von Kaenel H.‐M.
Published: September 2004

Lead and copper isotopes of Roman Imperial copper coins (denominations as and quadrans) were analysed by MC–ICP–MS. We concentrated on well‐dated coins minted at the official mint of Rome under the Emperors Augustus and Tiberius (between 16 bc and ad 37). The lead isotope results were compared with published lead isotope data of ore bodies from the Aegaean, Cyprus, Italy and Spain, in order to fingerprint the sources of Roman copper. During the Augustan period the main copper supply, as judged from the copper coins, is from Sardinia and south‐east Spain, with minor contributions from Tuscany. Except for Tuscany, this continued into the Tiberian period, when Cypriot copper also appears. Augustan quadrantes and late Tiberian asses came solely from the Rio Tinto area in south‐west Spain. Copper isotopes were applied here for the first time to systematic archaeometric studies. They are supplementary to lead isotopes and allow further grouping and classification of the copper coins.
Rubidium hydroxide polyethylene glycol crown ether in the conservation of old master paintings*
Authors: Hilfrich U. , Weser U.
Published: September 2004

The development of new, gentler methods for the conservation of Old Master paintings, with an emphasis on the removal or thinning of deteriorated varnish, is of high priority. In the course of the deterioration process, oxidative attacks lead to progressive formation of carboxylic acid groups, while many ester bondings are expected to be weakened. A stable RbOH polyethylene glycol complex was a promising tool to react with these moieties and to successfully break down the polymeric varnish layer. The remnants were easily wiped off mechanically. Control studies employing 86RbOH and 14C polyacrylate showed the complete absence of residual cleansing components on the paint surface.
Temperature‐Sensitive Random Insulin Granule Diffusion is a Prerequisite for Recruiting Granules for Release
Authors: Ivarsson Rosita , Obermüller Stefanie , Rutter Guy A. , Galvanovskis Juris , Renström Erik
Published: September 2004

Glucose‐evoked insulin secretion exhibits a biphasic time course and is associated with accelerated intracellular granule movement. We combined live confocal imaging of EGFP‐labelled insulin granules with capacitance measurements of exocytosis in clonal INS‐1 cells to explore the relation between distinct random and directed modes of insulin granule movement, as well as exocytotic capacity. Reducing the temperature from 34 °C to 24 °C caused a dramatic 81% drop in the frequency of directed events, but reduced directed velocities by a mere 25%. The much stronger temperature sensitivity of the frequency of directed events (estimated energy of activation ∼ 135 kJ/mol) than that of the granule velocities (∼ 22 kJ/mol) suggests that cooling‐induced suppression of insulin granule movement is attributable to factors other than reduced motor protein adenosine 5′‐triphosphatase activity. Indeed, cooling suppresses random granule diffusion by ∼ 50%. In the single cell, the number of directed events depends on the extent of granule diffusion. Finally, single‐cell exocytosis exhibits a biphasic pattern corresponding to that observed in vivo, and only the component reflecting 2nd phase insulin secretion is affected by cooling. We conclude that random diffusive movement is a prerequisite for directed insulin granule transport and for the recruitment of insulin granules released during 2nd phase insulin secretion.
Insulin and Oleate Promote Translocation of Inosine‐5′ Monophosphate Dehydrogenase to Lipid Bodies
Authors: Whitehead Jonathan P. , Simpson Fiona , Hill Michelle M. , Thomas Elaine C. , Connolly Lisa M. , Collart Frank , Simpson Richard J. , James David E.
Published: September 2004

In the present study we identify inosine‐5′ monophosphate dehydrogenase (IMPDH), a key enzyme inde novoguanine nucleotide biosynthesis, as a novel lipid body‐associated protein. To identify new targets of insulin we performed a comprehensive 2‐DE analysis of32P‐labelled proteins isolated from 3T3‐L1 adipocytes (Hill et al. J Biol Chem 2000; 275: 24313–24320). IMPDH was identified by liquid chromatography/tandem mass spectrometry as a protein which was phosphorylated in a phosphatidylinositol (PI) 3‐kinase‐dependent manner upon insulin treatment. Although insulin had no significant effect on IMPDH activity, we observed translocation of IMPDH to lipid bodies following insulin treatment. Induction of lipid body formation with oleic acid promoted dramatic redistribution of IMPDH to lipid bodies, which appeared to be in contact with the endoplasmic reticulum, the site of lipid body synthesis and recycling. Inhibition of PI 3‐kinase blocked insulin‐ and oleate‐induced translocation of IMPDH and reduced oleate‐induced lipid accumulation. However, we found no evidence of oleate‐induced IMPDH phosphorylation, suggesting phosphorylation and translocation may not be coupled events. These data support a role for IMPDH in the dynamic regulation of lipid bodies and fatty acid metabolism and regulation of its activity by subcellular redistribution in response to extracellular factors that modify lipid metabolism.
Missorting of LaCrosse Virus Nucleocapsid Protein by the Interferon‐Induced MxA GTPase Involves Smooth ER Membranes
Authors: Reichelt Mike , Stertz Silke , Krijnse‐Locker Jacomine , Haller Otto , Kochs Georg
Published: September 2004

The interferon‐induced human MxA protein belongs to the class of dynamin‐like, large guanosine‐5′‐triphosphatases that are involved in intracellular vesicle trafficking and organelle homeostasis. MxA shares many properties with the other members of this protein superfamily, including the propensity to self‐assemble and to associate with lipid membranes. However, MxA is unique in that it has antiviral activity and inhibits the replication of several RNA viruses. Here, we determined the role of membranes for the antiviral function of MxA using LaCrosse‐bunyavirus (LACV). We show that MxA does not affect trafficking and sorting of viral glycoproteins but binds and mislocates the viral nucleocapsid (N) protein into membrane‐associated, large perinuclear complexes. We further demonstrate that MxA localizes to a subcompartment of the smooth endoplasmic reticulum where the viral N protein accumulates. In infected MxA‐expressing cells, oligomeric MxA/N complexes are formed in close association with COP‐I‐positive vesicular–tubular membranes. Our results suggest that this membrane compartment is the preferred place where MxA and N interact, leading to efficient sequestration and missorting of an essential viral component.
Rab Coupling Protein Associates with Phagosomes and Regulates Recycling from the Phagosomal Compartment
Authors: Damiani María T. , Pavarotti Martín , Leiva Natalia , Lindsay Andrew J. , McCaffrey Mary W. , Colombo Maria I.
Published: September 2004

The Rab coupling protein (RCP) is a recently identified novel protein that belongs to the Rab11‐FIP family. RCP interacts specifically with Rab4 and Rab11, small guanosine‐5′‐triphosphatases that function as regulators along the endosomal recycling pathway. We used fluorescence confocal microscopy and biochemical approaches to evaluate the participation of RCP during particle uptake and phagosome maturation. In macrophages, RCP is predominantly membrane‐bound and displays a punctuate vesicular pattern throughout the cytoplasm. RCP is mainly associated with transferrin‐containing structures and Rab11‐labeled endosomes. Overexpression of H13, the carboxyl‐terminal region of RCP that contains the Rab binding domain, results in an abnormal endosomal compartment. Interestingly, we found that RCP is associated as discrete patches or protein domains to early phagosomal membranes. In macrophages, overexpression of full‐length RCP stimulates recycling from the phagosomal compartment, whereas overexpression of H13 diminishes this vesicular transport step. It is likely that acting as an intermediate between Rab4 and Rab11, RCP regulates membrane flux along the phagocytic pathway via recycling events.
Endocytic and Transcytotic Processes in Villous Syncytiotrophoblast: Role in Nutrient Transport to the Human Fetus
Authors: Fuchs Renate , Ellinger Isabella
Published: September 2004

The supply of nutrients to the developing fetus is a major function of the human hemochorial placenta, a placenta type in which the fetal chorion is in direct contact with the maternal blood. At term, nutrients have to be transported across two cell layers in chorionic villi, the syncytiotrophoblast (STB) and fetal endothelial cells. The STB is a continuous syncytium covering the entire surface of chorionic villi. This polarized epithelium is specialized in exchange processes and membrane trafficking between the apical membrane facing the maternal blood and the basal membrane facing the fetal endothelium. To meet placental and fetal requirements, the STB selectively takes up and transports a variety of nutrients, hormones, growth factors and cytokines and also transfers passive immunity to the fetus by receptor‐mediated transcytosis. In this review in vivo and in vitro systems currently used to study STB functions are discussed and the potential mechanisms of transplacental IgG, iron, lipoprotein and glucose transport are presented. As revealed in this article, the placenta is a tissue where intensive cell biological research is required to unravel endocytic trafficking pathways in a highly specialized cell such as the STB.
Regulation of Myosin‐VI Targeting to Endocytic Compartments
Authors: Dance Amber L. , Miller Matthew , Seragaki Shinobu , Aryal Prafulla , White Breanne , Aschenbrenner Laura , Hasson Tama
Published: September 2004

Myosin‐VI has been implicated in endocytic trafficking at both the clathrin‐coated and uncoated vesicle stages. The identification of alternative splice forms led to the suggestion that splicing defines the vesicle type to which myosin‐VI is recruited. In contrast to this hypothesis, we find that in all cell types examined, myosin‐VI is associated with uncoated endocytic vesicles, regardless of splice form. GIPC, a PDZ‐domain containing adapter protein, co‐assembles with myosin‐VI on these vesicles. Myosin‐VI is only recruited to clathrin‐coated vesicles in cells that express high levels of Dab2, a clathrin‐binding adapter protein. Overexpression of Dab2 is sufficient to reroute myosin‐VI to clathrin‐coated pits in cells where myosin‐VI is normally associated with uncoated vesicles. In normal rat kidney (NRK) cells, which express high endogenous levels of Dab2, splicing of the globular tail domain further modulates targeting of ectopically expressed myosin‐VI. Although myosin‐VI can be recruited to clathrin‐coated pits, we find no requirement for myosin‐VI motor activity in endocytosis in NRK cells. Instead, our data suggest that myosin‐VI recruitment to clathrin‐coated pits may be an early step in the recruitment of GIPC to the vesicle surface.
Evaluation of Standard ERP Software Implementation Approaches in Terms of their Capability for Business Process Optimization
Authors: Knoell Heinz-D. , Kuehl , Lukas W. H. , Kuehl Roland W. A. , Moreton Rob
Published: September 2004

In spite of the great variety of potential advantages, it is also necessary to illuminate the real effects of Standard ERP Software in practice. Recent studies have revealed that 81% of German companies interviewed using SAP, do not fully exploit the software’s ability to optimize business processes, though 61% stated that SAP offers very good process optimization opportunities. (CSC Ploenzke AG, 2002, “European SAP Practice, Umfrageergebnisse,” SAPphire 2000). Therefore we evaluated popular life cycle models with respect to their suitability to implement Standard Software in a process driven way (Kuehl, R.W.A., and Knoell, H.-D., 2002, “Evaluation of Topical Approaches to the Implementation of Standardised ERP-Systems,” Proc. ETCE 2002, CD, ASME Petroleum Division, Houston, TX).
AMPS-An Automated Modular Process Planning System
Authors: Castelino Kenneth , Sundararajan V. , D’Souza Roshan , Kannan Balaji , Wright Paul. K.
Published: September 2004

AMPS is a fully automated process planning system for milling of 2.5D parts. It consists of different modules, each of which performs specific tasks like identification of removal volumes, setup and fixture planning, tool selection and tool path planning. This article focuses on the architecture of the planning system, the integration of the different modules and the interfaces needed for smooth flow of information between these modules. Current computer aided process planning (CAPP) practices were considered while defining interfaces so that these modules can be easily integrated into a commercial CAPP system.
Approximate Geometric Methods in Application to the Modeling of Fiber Placed Composite Structures
Authors: Schueler Kurt , Miller James , Hale Richard
Published: September 2004

Fiber placement is a modern method of constructing composite structures with complex curved surfaces. Modeling individual tows in a fiber placed part constitutes the challenge addressed by methods presented in this paper. One method is presented to approximate offset curves on a free form surface using the geometric constraints of the fiber placement process. A second method is presented to approximate a curve on a free form surface that can be used to generate a laminate family ply. We demonstrate that these approximation methods are sufficient for the accuracy of the fiber placement machine.
Development of XML Databinding Integration for Web-Enabled Aircraft Engine Simulation
Authors: Lin Risheng , Afjeh Abdollah A.
Published: September 2004

This paper discusses the detailed design and implementation of an XML databinding framework for Web-based aircraft engine simulation. The framework provides an interoperable, high-level object interface to access data. The interface permits semantic validation of engine data while preserving the meaning of the original data. Using this framework makes the integration of engine model and data, along with the relevant interfaces required for sharing and validation engine data, easier and more efficient. The language-independent representation of engine component data enables users to move around XML data using HTTP through disparate networks. The application of this framework is demonstrated via a Web-based turbofan propulsion system simulation using the World Wide Web (WWW). The framework employs a Java Servlet-based Web component architecture that renders XML engine data into HTML format and handles the user’s input events. This feature allows users to conduct and manage engine simulations from a Web browser. The simulation data can be saved to a local disk for archiving or restarting the simulation at a later time.
Generation of Defects Due to Machining of TiAl Intermetallic Compound and Their Effects on Mechanical Strength
Authors: Furusawa Toshiaki , Hino Hiroshi , Tsuji Sinji , Koroyasu Sadatoshi , Ichikawa Atsushi
Published: September 2004

The generation of machining defects and their effect on bending strength characteristics are discussed with respect to a TiAl intermetallic compound, which is attracting much attention as a high-temperature structural material because of its high specific strength. The discussion focuses on the mechanism of the formation of edge chipping and machined surface cracks during cutting of a TiAl intermetallic compound. Also, some effects of these machining defects on the bending strength are clarified. The comparison of cutting results with abrasive machining results helps clarify the dependence of strength on undeformed chip thickness during chip generation of machining processes.
Brittle to Plastic Transition in the Dynamic Mechanical Behavior of Partially Saturated Granular Materials
Authors: Iveson Simon M. , Page Neil W.
Published: September 2004

The effect of liquid viscosity, surface tension and strain rate on the deformation behavior of partially saturated granular material was studied over a ten order of magnitude range of capillary number (the ratio of viscous to capillary forces). Glass spheres of average size 35 microns were used to make pellets of 35% porosity and 70% liquid saturation. As the capillary number increased, the failure mode changed from brittle cracking to ductile plastic flow. This change coincided with the transition from strain-rate independent flow stress to strain-rate dependent flow stress noted previously [Iveson, S. M., Beathe, J. A., and Page, N. W., 2002, “The Dynamic Strength of Partially Saturated Powder Compacts: The Effect of Liquid Properties,” Powder Technol., 127, pp. 149–161]. This change in failure mode is somewhat counter-intuitive, because it is the opposite of that observed for fully saturated slurries and pastes, which usually change from plastic to brittle with increasing strain rate. A model is proposed which predicts the functional dependence of flow stress on capillary number and also explains why the flow behavior changes. When capillary forces dominate, the material behaves like a dry powder: Strain occurs in localized shear planes resulting in brittle failure. However, when viscous forces dominate, the material behaves like a liquid: Shear strain becomes distributed over a finite shear zone, the size of which increases with strain rate. This results in less strain in each individual layer of material, which promotes plastic deformation without the formation of cracks. This model also explains why the power-law dependency of stress on strain rate was significantly less than the value of 1.0 that might have been expected given that the interstitial liquids used were Newtonian.
Development of a Finite Element Cable Model for Use in Low-Tension Dynamics Simulation
Authors: Buckham Brad , Driscoll Frederick R. , Nahon Meyer
Published: September 2004

To accurately simulate the motion of slack marine cables, it is necessary to capture the effects of the cable’s bending and torsional stiffness. In this paper, a computationally efficient and novel third-order finite element is presented that provides a representation of both the bending and torsional effects and accelerates the convergence of the model at relatively large element sizes. Using a weighted residual approach, the discretized motion equations for the new cubic element are developed. Applying inter-element constraint equations, we demonstrate how an assembly of these novel elemental equations can be significantly reduced to prevent the growth of the system equations normallly associated with such higher order elements and allow for faster evaluation of the cable dynamics in either taut or low-tension situations.
A Definition of Particle Rolling in a Granular Assembly in Terms of Particle Translations and Rotations
Authors: Bagi Katalin , Kuhn Matthew R.
Published: September 2004

The paper presents a definition of particle rolling for the interactions of two and three-dimensional particles of arbitrary shape, in case of infinitesimal particle translations and rotations. The definition is based on a purely kinematical analysis, and it is shown to satisfy the objectivity condition.
Rayleigh Waves in Anisotropic Crystals Rotating About the Normal to a Symmetry Plane
Authors: Destrade M.
Published: September 2004

The propagation of surface acoustic waves in a rotating anisotropic crystal is studied. The crystal is monoclinic and cut along a plane containing the normal to the symmetry plane; this normal is also the axis of rotation. The secular equation is obtained explicitly using the “method of the polarization vector,” and it shows that the wave is dispersive and decelerates with increasing rotation rate. The case of orthorhombic symmetry is also treated. The surface wave speed is computed for 12 monoclinic and 8 rhombic crystals, and for a large range of the rotation rate/wave frequency ratio.
On the Use of a Kolsky Torsion Bar to Study the Transient Large-Strain Response of Polymer Melts at High Shear Rates
Authors: Hu Y. , Feng R.
Published: September 2004

A Kolsky torsion bar is utilized successfully in a novel rheometric experiment for measuring the transient large-strain response of polymer melts under high shear-rate loading. A molten low-density polyethylene is studied with the new technique. The results show that the high-rate shear response of the material has an instantaneous rate dependence that may not be discernible at low rates and a strain-dependent hardening that saturates at large strains instead of fading. The usefulness of the technique and the significance of the findings are discussed in comparison with a modified rubberlike liquid theory and high-rate capillary measurements for low-density polyethylene melts.
Immersive Virtual Reality In Cable and Pipe Routing: Design Metaphors and Cognitive Ergonomics
Authors: O’B Holt P. , Ritchie , J. M , Day , P. N. , Simmons , J. E. L. , Robinson , G. , Russell , G. T. , Ng F. M.
Published: September 2004

In recent years there have been moves in industrial engineering towards greater automation through intelligent systems and this has resulted in replacing human expertise. In many cases the potential of intelligent systems has yet to be realised. This paper presents and discusses an alternative technological approach, which uses immersive virtual reality (VR) to support engineering design tasks. The approach focuses on the human engineer and acknowledges the importance of human input to the design process. The development of a metaphor based VR system is reported along with initial field trials, which compare VR with conventional CAD systems. The results show advantages of using VR over CAD and these are discussed along with strengths, weaknesses and future work.
Fluid Performance Study for Groove Grinding a Nickel-Based Superalloy Using Electroplated Cubic Boron Nitride (CBN) Grinding Wheels
Authors: Gift, Frank C. , Misiolek Wojciech Z.
Published: September 2004

The performance of three water-based grinding fluids was analyzed and compared to a neat oil tested under the same process conditions. Light optical and scanning electron microscopy observations show the mechanism of metal deposition that leads to CBN wheel failure for water-based fluids. To improve the performance of the water-based fluids, a new nozzle layout is proposed that would prevent metal deposition on the CBN wheels. The proposed solution is not chemical, but mechanical in nature and the presented setting should be optimized in the future to assure satisfactory performance of the CBN wheels with water-based fluids.
Data Mining for Subassembly Selection
Authors: Agard Bruno , Kusiak Andrew
Published: September 2004

The paper presents a model and an algorithm for selection of subassemblies based on the analysis of prior orders received from the customers. The parameters of this model are generated using association rules extracted by a data mining algorithm. The extracted knowledge is applied to construct a model for selection of subassemblies for timely delivery from the suppliers to the contractor. The proposed knowledge discovery and optimization framework integrates the concepts from product design and manufacturing efficiency. The ideas introduced in the paper are illustrated with an example and an automotive case study.
Modeling of Forces for Drills With Chip-Breaking Grooves
Authors: Sahu Sushanta K. , DeVor Richard E. , Kapoor Shiv G.
Published: September 2004

In this paper, a mechanistic modeling approach to predicting cutting forces for conical twist drills with chip-breaking grooves has been developed. The model is based on force principles for restricted contact cutting extended to take into account the presence of a groove on the drill rake face. The applicability of the model for arbitrary groove geometries has been ensured by eliminating the use of grooved drills in the calibration process. Four different combinations of groove geometries have been used for validating the model using high speed steel drills and low carbon steel workpiece material. The force predictions from the model were found to be in good agreement with the measured forces. The model was then employed to determine groove orientation and design parameters that minimize cutting forces, subject to the condition that chip breaking is satisfactory.
Vibration Frequencies in High-Speed Milling Processes or a Positive Answer to Davies, Pratt, Dutterer and Burns
Authors: Insperger T. , Ste´pa´n G.
Published: September 2004

The stability charts of high-speed milling are constructed. New unstable regions and vibration frequencies are identified. These are related to flip bifurcation, i.e. period doubling vibrations occur apart of the conventional self-excited vibrations well-known for turning or low-speed milling with multiple active teeth. The Semi-Discretization method is applied for the delayed parametric excitation model of milling providing the connection of the two existing and experimentally verified results of machine tool chatter research. The two extreme models in question, that is, the traditional autonomous delayed model of time-independent turning, and the recently introduced discrete map model of time-dependent highly interrupted machining, are both involved as special cases in the universal approach presented in this study.
Contribution of Support Means to Stresses Developed in Sheet Metal Coils
Authors: Lee Y. M. , Wickert J. A.
Published: September 2004

Sheet metal is often stored in large wound coils and processed through such manufacturing stages as cleaning, coating, and slitting in a finishing plant or thickness reduction in a rolling mill. During winding and unwinding operations, as well as during storage and transportation, a coil can be supported in a variety of methods. The coil can be formed on a relatively compliant fiber core, or it can be mounted with the core onto a drive shaft or a pair of core chucks. The stresses within the coil develop in response to the sheet metal’s material properties, the process tension, and the type of support condition that is present along the coil’s inner diameter. In this investigation, a two-dimensional finite element model is applied to capture the stress distribution within sheet metal coils. The influence of support condition on the state of stress is investigated for sheet metal on a core alone, and for the cases in which the coil is supported by a drive shaft or core chucks during winding. The radial and width-wise variations of the stress components are calculated and compared in the light of the differences in compliance between the three means of support.
A Distance Function Based Approach for Localization and Profile Error Evaluation of Complex Surface
Authors: Zhu LiMin , Xiong ZhenHua , Ding Han , Xiong YouLun
Published: September 2004

This paper presents a unified framework for best-fitting of complex rigid surface to measured 3-D coordinate data by adjusting its location (position/orientation). For a point expressed in the machine reference frame and a nominal surface represented in its own model frame, a signed point-to-surface distance function is defined, and its properties are investigated, especially, its increment with respect to the differential motion of the surface, up to the second order, is derived. On this basis, localization and profile error evaluation of complex surface are formulated as a nonlinear least-squares problem and nonlinear constrained optimization problem respectively, and sequential approximation algorithms are developed to solve them. The two algorithms have the advantages of implementational simplicity, computational efficiency and robustness. Also strategies for estimating initial solution and compensating probe radius are presented. Examples confirm the validity of the proposed approach.
Steady State Hydraulic Valve Fluid Field Estimator Based on Non-Dimensional Artificial Neural Network (NDANN)
Authors: Cao M. , Wang K. W. , DeVries L. , Fujii , Y. , Tobler , W. E. , Pietron , G. M. , Tibbles , T. , McCallum J.
Published: September 2004

An automatic transmission (AT) hydraulic control system includes many spool-type valves that have highly asymmetric flow geometry. A simplified flow field model based on a lumped geometry is computationally efficient. However, it often fails to account for asymmetric flow characteristics, leading to an inaccurate analysis. An accurate analysis of their flow fields typically requires using the computational fluid dynamics (CFD) technique, which is numerically inefficient and time consuming. In this paper, a new hydraulic valve fluid field model is developed based on non-dimensional artificial neural networks (NDANNs) to provide an accurate and numerically efficient tool in AT control system design applications. A grow-and-trim procedure is proposed to identify critical non-dimensional inputs and optimize the network architecture. A hydraulic valve testing bench is designed and built to provide data for neural network model development. NDANN-based fluid force and flow rate estimators are established based on the experimental data. The NDANN models provide more accurate predictions of flow force and flow rates under broad operating conditions (such as different pressure drops and valve openings) compared with conventional lumped flow field models. Because of its non-dimensional characteristic, the NDANN fluid field estimator also exhibits good input-output scalability, which allows the NDANN model to estimate the fluid force and flow rate even when the operating condition parameter or design geometry parameters are outside the range of the training data. That is, although the operating/geometry parameter values are outside the range of the training sets, the non-dimensional values of the specific operating/geometry parameters are still within the training range. This feature makes the new model a potential candidate as a system design tool.
Comparison of Non-Nominal Geometry Models Represented in Physical Versus Virtual Environments
Authors: Wickman Casper , So¨derberg Rikard
Published: September 2004

By combining Computer Aided Tolerance (CAT) simulation tools with Virtual Reality (VR) tools, virtual environments for non-nominal geometry verification can be utilized. This paper presents the results from an experimental study, conducted at Volvo Car Corporation, which investigates the perceptional aspects that are related to verification of visual quality appearance, using non-nominal virtual models. Although a realistic non-nominal model is created, the interpretation, i.e. how the model is perceived, must be clarified. Since the effect of geometric variation is a specific application, with high demands on realistic and detailed representation, perceptional studies are needed to ensure that VR and other virtual representations can be used for this kind of application. In this paper, two environments are compared, one physical and one corresponding virtual environment. Three adjusted physical vehicles are mapped to the virtual environment and compared using non-immersive desktop VR in a visualization experiment with test subjects from the automotive industry. The study indicates that virtual objects are judged as less good-looking compared to physical objects. There is also a higher degree of uncertainness when judging virtual objects.
Added Stability Lobes in Machining Processes That Exhibit Periodic Time Variation, Part 1: An Analytical Solution
Authors: Corpus William T. , Endres William J.
Published: September 2004

An added family of stability lobes, which exists in addition to the traditional stability lobes, has been identified for the case of periodically time varying systems. An analytical solution of arbitrary order is presented that identifies and locates multiple added lobes. The stability limit solution is first derived for zero damping where a final closed-form symbolic result can be realized up to second order. The un-damped solution provides a mathematical description of the added lobes’ locations along the speed axis, an added-lobe numbering convention, and the asymptotes for the damped case. The derivation for the damped case permits a final closed-form symbolic result for first-order only; the second-order solution requires numerical evaluation. The easily computed analytical solution is shown to agree well with the results of the computationally intensive numerical simulation approach. An increase in solution order improves the agreement with numerical simulation; but, more importantly, it allows equivalently more added lobes to be predicted, including the second added lobe that cuts into the speed regime of the traditional high-speed stability peak.
A Hybrid Draw Die Optimization Technique for Sheet Metal Forming
Authors: Scott-Murphy Adrian , Kalyanasundaram S. , Cardew-Hall M. , Hodgson Peter
Published: September 2004

Recent years have seen considerable advances in the use of Finite Element (FE) modeling techniques, to the point where they can be used confidently to predict the output of the sheet metal forming system. The limiting factor in the use of FE analysis in the optimization process is now shifting from the accuracy of simulations, to the time required to optimize the system. This paper proposes a new approach aimed at reducing the time to optimize a draw die design, through a combination of Finite Element Modeling, semi-analytical models, and a knowledge based expert system.
Multi Frequency Solution of Chatter Stability for Low Immersion Milling
Authors: Merdol S. D. , Altintas Y.
Published: September 2004

Finish milling is usually required in the peripheral milling of thin aircraft webs with long end mills, where the structures are flexible and radial depths of cut are small. The spindle speed and depth of cut must be selected optimally to avoid both forced and chatter vibrations, which in turn enables production of the parts within specified tolerances. Recent articles show that stability pockets differ at certain speeds when the radial immersion in milling is low and the machining process is highly intermittent. This paper presents a stability theory which predicts chatter stability lobes that are not covered by classical chatter theories in which the coupling between the spindle speed and process stability are neglected. The dynamics of low radial immersion milling are formulated as an eigenvalue problem, where harmonics of the tooth spacing angle and spread of the transfer function with the harmonics of the tooth passing frequencies are considered. It is shown that the stability lobes are accurately predicted with the presented method. This paper details the physics involved when the tooth passing frequencies alter the effective transfer function of the structure in the stability solution. The products of the harmonics of the directional coefficients and transfer functions of the structure are evaluated at the natural mode under the influence of tooth passing frequency harmonics in order to obtain the exact locations of chatter stability lobes.