Bibliografie tematiche / Interface de contact

Letteratura scientifica selezionata sul tema "Interface de contact"

Autore: Grafiati

Pubblicato: 1 giugno 2024

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Articoli di riviste sul tema "Interface de contact":

Kim, Youngbeom, Sungho Choi, Kyung-Young Jhang e Taehyeon Kim. "Experimental Verification of Contact Acoustic Nonlinearity at Rough Contact Interfaces". Materials 14, n. 11 (31 maggio 2021): 2988. http://dx.doi.org/10.3390/ma14112988.

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When a longitudinal wave passes through a contact interface, second harmonic components are generated due to contact acoustic nonlinearity (CAN). The magnitude of the generated second harmonic is related to the contact state of the interface, of which a model has been developed using linear and nonlinear interfacial stiffness. However, this model has not been sufficiently verified experimentally for the case where the interface has a rough surface. The present study verifies this model through experiments using rough interfaces. To do this, four sets of specimens with different interface roughness values (Ra = 0.179 to 4.524 μm) were tested; one set consists of two Al6061-T6 blocks facing each other. The second harmonic component of the transmitted signal was analyzed while pressing on both sides of the specimen set to change the contact state of the interface. The experimental results showed good agreement with the theoretical prediction on the rough interface. The magnitude of the second harmonic was maximized at a specific contact pressure. As the roughness of the contact surface increased, the second harmonic was maximized at a higher contact pressure. The location of this maximal point was consistent between experiments and theory. In this study, an FEM simulation was conducted in parallel and showed good agreement with the theoretical results. Thus, the developed FEM model allows parametric studies on various states of contact interfaces.

VANDAMME, L. K. J. "CHARACTERIZATION OF CONTACT INTERFACE, FILM SHEET RESISTANCE AND 1/f NOISE WITH CIRCULAR CONTACTS". Fluctuation and Noise Letters 10, n. 04 (dicembre 2011): 467–84. http://dx.doi.org/10.1142/s0219477511000740.

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The resistance and noise of films prepared with poor contacts are dominated by the contact interface and for perfect contacts holds that resistance and noise stem from outside the contact interface region. The proposed test pattern to study the different contributions uses one mask. It permits two- and four-point measurements enabling the detection of a weak contribution from outside the contact interface on top of a strong interface contribution. The resistance and noise for poor and perfect contacts are calculated between pairs of circular top electrodes of equal diameters 2r at distances L with L/2r = 10. The dependences of resistance and noise on the contact diameter are quite different for perfect and poor contacts. 1/f noise of films taken from literature are compared in the noise figure of merit K = Cus [ cm 2]/Rsh[Ω]. K is the ratio of 1/f noise normalized for bias, frequency and unit surface to sheet resistance. Materials can be classified based on K-values. Very high K-values point to inhomogeneous electric fields on a microscopic scale (percolation conduction). The contact interface 1/f noise and specific contact resistance are characterized by Cust [ cm 2] and ρct [Ω cm 2]. Reviews of K for films and Cust for interfaces show that 1/f noise is a more sensitive tool than merely the resistance parameters Rsh and ρct.

Nimmala, Seshu, S. Aria Hosseini, Jackson Harter, Todd Palmer, Eric Lenz e P. Alex Greaney. "Characterizing Macroscopic Thermal Resistance Across Contacting Interfaces Through Local Understanding of Thermal Transport". MRS Advances 3, n. 44 (2018): 2735–41. http://dx.doi.org/10.1557/adv.2018.485.

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ABSTRACTThermal resistance across the interface between touching surfaces is critical for many industrial applications. We developed a network model to predict the macroscopic thermal resistance of mechanically contacting surfaces. Contacting interfaces are fractally rough, with small islands of locally intimate contact separated by regions with a wider gas filled boundary gap. Heat flow across the interface is therefore heterogeneous and thus the contact model is based on a network of thermal resistors representing boundary resistance at local contacts and the access resistance for lateral transport to contacts. Molecular dynamics simulations have been performed to characterize boundary resistance of Silicon Alumina interfaces for testing the sensitivity of thermal resistance to contact opening. Boltzmann transport simulations of access resistance in Si are conducted in the ballistic transport regime.

Yang, Ai Mei, Gui Zhong Li, Shao Ying Zhen e Lai Jun Liu. "Electrode Interface Polarization in BaTiO₃-Based PTC Ceramics". Key Engineering Materials 697 (luglio 2016): 248–52. http://dx.doi.org/10.4028/www.scientific.net/kem.697.248.

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Electrodes play a vital role on the electrical properties of positive temperature coefficient (PTC) ceramics. An ohmic contract between ceramics and electrodes is necessary for the PTC effect. In this work, silver mixed aluminium electrode and pure silver electrode were pasted on BaTiO3-based PTC ceramics, which results in an ohmic contact and non-ohmic contact, respectively. Impedance spectroscopy and dielectric and conductivity properties was investigated at different temperature for the two contacts. Small difference of electrical properties was found between the two contacts above the Curie temperature. Below the Curie temperature, however, carriers could pass through the interface of ohmic contract but gather on the interface of non-ohmic contact. The latter resulted in a space charge polarization, which increased low-frequency dielectric permittivity.

Shi, Linquan, e Qiang Li. "Numerical simulation and experimental study of contact thermal resistance under high temperature conditions". Thermal Science and Engineering 5, n. 1 (27 febbraio 2022): 1. http://dx.doi.org/10.24294/tse.v5i1.1523.

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Contact thermal resistance is an important indicator of the efficiency of heat transfer between contact interfaces.The contact thermal resistance between the interfaces of superalloy GH4169 in high temperature was investigated byusing ANSYS. The real surface morphology of superalloy was obtained with optical microscope, and its surface modelwas reconstructed in ANSYS. Based on the theory of structural mechanics, the elastoplastic deformation of the microstructure of the contact interface is simulated, and analyzed and obtained the contact thermal resistance between contactinterfaces. The effect of interface temperature on the radiative heat transfer between the contact interfaces was studied.At the same time, the impact of radiation heat transfer between contact interfaces in high temperature is considered.Finally, it was tested by using an experimental test device. The result show that the maximum deviation between thecontact thermal resistance and the contact thermal resistance was 12.60%, and the contact thermal resistance betweensuperalloy interfaces decreases with the increase of interface temperature and contact pressure; the contact interfacetemperature difference increases first and then decreases with the increase of interface temperature.

Banerjee, Sneha, e Peng Zhang. "Review of recent studies on nanoscale electrical junctions and contacts: Quantum tunneling, current crowding, and interface engineering". Journal of Vacuum Science & Technology A 40, n. 3 (maggio 2022): 030802. http://dx.doi.org/10.1116/6.0001724.

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The study of charge carrier transport at nanoscale electrical contacts is crucial for the development of next-generation electronics. This paper reviews recent modeling efforts on quantum tunneling, current crowding, and contact resistance across electrical interfaces with nanometer scale dimensions. A generalized self-consistent model for quantum tunneling induced electron transport in metal–insulator–metal (MIM) junctions is summarized. Rectification of a dissimilar MIM junction is reviewed. A modified two-dimensional (2D) transmission line model is used to investigate the effects of spatially varying specific contact resistivity along the contact length. The model is applied to various types of electrical contacts, including ohmic contacts, MIM junction based tunneling contacts, and 2D-material-based Schottky contacts. Roughness engineering is recently proposed to offer a possible paradigm for reducing the contact resistance of 2D-material-based electrical contacts. Contact interface engineering, which can mitigate current crowding near electrical contacts by spatially designing the interface layer thickness or properties, without requiring an additional material or component, is briefly reviewed. Tunneling engineering is suggested to eliminate severe current crowding in highly conductive ohmic contacts by introducing a thin tunneling layer or gap between the contact members. Unsolved problems and challenges are also discussed.

Kartal, Mehmet E., Daniel M. Mulvihill, David Nowell e Dawid A. Hills. "Measurement of Tangential Contact Stiffness in Frictional Contacts: The Effect of Normal Pressure". Applied Mechanics and Materials 70 (agosto 2011): 321–26. http://dx.doi.org/10.4028/www.scientific.net/amm.70.321.

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The tangential contact stiffness of frictional interfaces affects both the vibration response and structural integrity of structures comprising frictional joints. Vibration and structural response of monolithic structures can be predicted very accurately; however, when assemblies of components involve frictional interfaces, additional damping and compliance are present due to these interfaces. These features make it more challenging to predict the vibration characteristics of assemblies with the same degree of accuracy as can be achieved for single components. If these interface properties can be determined, it should then be possible to significantly enhance current models of the vibration of engineering assemblies. Measurements of both force and displacement in the tangential direction are obtained from a series of in-line fretting tests involving flat pads with rounded corners clamped against the flat surface of a specimen which is oscillated by a hydraulic tensile testing machine. In order to measure the local displacement field very close to the contact interface, the digital image correlation (DIC) method is employed. The effect of normal contact pressure on tangential contact stiffness is investigated. Multiple experiments with the same parameters show good repeatability given the number of variables involved.

Liu, Yuwei, Yameng Ji, Fuhao Ye, Weizheng Zhang e Shujun Zhou. "Effects of contact pressure and interface temperature on thermal contact resistance between 2Cr12NiMoWV/BH137 and γ-TiAl/2Cr12NiMoWV interfaces". Thermal Science 24, n. 1 Part A (2020): 313–24. http://dx.doi.org/10.2298/tsci191018470l.

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Thermal contact resistance between interfaces is an important parameter in the analysis of temperature distribution for structural components. Thermal contact resistance between heat resistant steel 2Cr12NiMoWV/aluminum alloy BH137 interfaces and 2Cr12NiMoWV/titanium alloy ?-TiAl interfaces were experimentally investigated in the present paper. The effects of contact pressure and interface tem-perature were detailed. The temperature of contacting surfaces was from 80- 250?, and the contact pressure ranged from 2-17 MPa. All experiments were conducted in ambient atmosphere. Results showed that thermal contact resistance decreases with an increment of interface temperature or contact pressure. Under the same conditions of contact pressure and interface temperature, thermal contact resistance between 2Cr12NiMoWV and BH137 interfaces is lower than that between 2Cr12NiMoWV and ?-TiAl interfaces. The temperature dependence of thermal conductivity and mechanical properties was analyzed to explain the results. Furthermore, with the piston and piston pin as the research object, steady state temperature fields were simulated in cases of considering thermal contact resistance and without considering thermal contact resistance, respectively. The results showed that the maximum temperature of the piston pin will be lower when thermal contact resistance is considered.

Nouira, Dorra, Davide Tonazzi, Anissa Meziane, Laurent Baillet e Francesco Massi. "Numerical and Experimental Analysis of Nonlinear Vibrational Response due to Pressure-Dependent Interface Stiffness". Lubricants 8, n. 7 (10 luglio 2020): 73. http://dx.doi.org/10.3390/lubricants8070073.

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Modelling interface interaction with wave propagation in a medium is a fundamental requirement for several types of application, such as structural diagnostic and quality control. In order to study the influence of a pressure-dependent interface stiffness on the nonlinear response of contact interfaces, two nonlinear contact laws are investigated. The study consists of a complementary numerical and experimental analysis of nonlinear vibrational responses due to the contact interface. The laws investigated here are based on an interface stiffness model, where the stiffness property is described as a nonlinear function of the nominal contact pressure. The results obtained by the proposed laws are compared with experimental results. The nonlinearity introduced by the interface is highlighted by analysing the second harmonic contribution and the vibrational time response. The analysis emphasizes the dependence of the system response, i.e., fundamental and second harmonic amplitudes and frequencies, on the contact parameters and in particular on contact stiffness. The study shows that the stiffness–pressure trend at lower pressures has a major effect on the nonlinear response of systems with contact interfaces.

Huang, Lingqin, Sumin Pan, Xuliang Deng e Wenwen Cui. "4H-SiC Ohmic contacts formation by MoS₂ layer intercalation: A first-principles study". Journal of Applied Physics 132, n. 24 (28 dicembre 2022): 245702. http://dx.doi.org/10.1063/5.0122722.

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Due to the difficulty of forming a low Schottky barrier at the interface of a metal/SiC contact, preparing Ohmic contacts is still a key technical problem in developing SiC devices. In this paper, the effects of MoS2 intercalation on the interface properties of metal/SiC (Al, Ag, Ti, Au, and Mg) systems were investigated by first-principles calculation. The calculations show that all the metal/SiC contacts exhibit p-type Schottky contacts with strong Fermi level pinning (FLP) at the interfaces. After inserting a layer of MoS2, the Schottky barrier heights are significantly reduced. All the metal/MoS2/SiC systems are tuned to be n-type Ohmic contacts. By calculating and analyzing electron localization functions, projected band structure, partial density of states, and planar-averaged charge density difference, the Ohmic contact formation mechanism may be due to the saturation of dangling bonds of the SiC surface, the reduction in metal-induced gap states, the formation of interface dipole layer, and the shift of FLP position to the interface of metal/MoS2.

Più fonti

Tesi sul tema "Interface de contact":

Bonari, Jacopo. "Novel interface discretisation methods for contact mechanics". Thesis, IMT Alti Studi Lucca, 2021. http://e-theses.imtlucca.it/326/1/Bonari_phdthesis.pdf.

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This thesis’ main scope is the presentation of two different methodologies for the analysis of contact problems involving morphologically complex or rough surfaces. Both approaches rely on the Finite Element Method (FEM) as the chosen computational framework. They hinge on the definition of an interface finite element used to model the space encompassed by two solids incontact. This kind of interface element is shared with the field of non-linear fracture mechanics, employed for the simulation of non-linear crack growth according to Cohesive Zone Model (CZM). Here, for the first time, the formulation is extensively applied to contact mechanics. With no further modifications, the interface element is suited for the solution of contact problems involving smooth and conformal interfaces, exploiting a node-to node approach and a penalty formulation for the enforcement of the contact constraints. The element is enriched with specific characteristics that allow for the solution of rough contact problems yet maintaining a very simple mesh discretisation, both using a single-scale and a multiscale approach. In the single-scale approach, a novel methodology is exploited that considers an equivalent flat interface and accounts for the actual geometry by a suitable correction of the standard normal gap. In the multi-scale approach, the Boundary Element Method (BEM) is exploited for solving, at a micro-scale, the normal contact problem of a rough rigid indenter making contact with an elastic half-space, according to a far-field displacement determined by the deformation imposed at a macro-scale. The solution in terms of averaged pressure and mean separation is then passed back to the macro-scale.

Quinn, Amy May. "The study of contact phenomena using ultrasound". Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271847.

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Jason, Bronwin Anastasia. "An adaptive user interface model for contact centres". Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/989.

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Contact centres (CC), are the primary interaction point between a company and its customers and these are rapidly expanding in terms of both workforce and economic scope. An important challenge for today's CC solutions is to increase the speed at which CCAs retrieve information to answer customer queries. CCAs, however, differ in their ability to respond to these queries and do not interact with the computer user interface (UI) in the same way as they each have different capabilities, experience and expertise. Studies have provided empirical support that user performance can be increased when the computer UI characteristics match the user skill level. Adaptive user interfaces (AUIs) are the key to creating personalised systems. Their sole task is to provide an interface most suitable to users' needs whilst facilitating the users' varying skill levels. The aim of this research was to develop an AUI model for CCs to support and improve the expertise level of CCAs. A literature review of CCs, user expertise, AUIs and existing AUI models resulted in the proposal of an AUI model for CCs. The proposed AUI model was described in terms of its architecture, component-level and interface design. An AUI prototype was developed as a proof-of-concept of the proposed AUI model. A literature review on existing AUI evaluation approaches resulted in an evaluation strategy for the proposed AUI model. The AUI prototype was evaluated according to the evaluation strategy that was identified. User testing incorporating eye-tracking and a post-test questionnaire was used to determine the usefulness and usability of the AUI prototype. Significant results were found with regards to user satisfaction ratings, the learnability of the AUI prototype and its effectiveness. This dissertation makes an important contribution in the design of an AUI model that supports and improves the expertise level of CCAs. The model could be used to assist the development of CC applications incorporating AUIs. Future research is however needed to evaluate the effect of the proposed AUI model in a larger CC environment.

Chevallier, Eddy. "Définition d'indices de qualité du contact glissant métallique : signature électrique de l'état de surface". Amiens, 2014. http://www.theses.fr/2014AMIE0119.

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La thèse concerne la construction d'une phénoménologie du contact glissant basée sur une approche multi-physique du contact. Nous appuyant sur une caractérisation expérimentale très riche du contact électrique glissant, nous avons construit un modèle théorique (de nature probabiliste) et numérique débouchant entre autre sur l'évaluation de la qualité du contact au travers de divers index de qualité combinant les grandeurs pertinentes du contact, toutes accessibles à la mesure. Le modèle prend en compte, outre la mécanique du contact, les composantes déterministes et aléatoires (profils de rugosité) de la géométrie des surfaces mises en jeu. Le développement du modèle numérique peut se faire selon deux stratégies très différentes. La première intègre des caractéristiques de modèles antérieurs de référence (Greenwood-Williamson,. . . ). La seconde offre l'avantage supplémentaire d'une étude des performances du contact en fonction de la nature des matériaux. De notre modèle statistique émerge un nouveau concept, l'entropie de contact, ainsi dénommée en raison de sa grande similitude avec I'entropie usuelle. Apparaissant comme une fonctionnelle de l'état de surface (géométrie, inhomogénéité chimique,. . . ), cette grandeur présente une grande sensibilité aux conditions de contact telles que la vitesse de glissement et la force de plaquage du contact, influençant directement le transfert de signaux électriques à travers le contact. Elle ouvre ainsi la double perspective d'une thermodynamique du contact glissant et de l'optimisation des états de surfaces en vue d'une qualité maitrisée du contact. Nous avons pu par ailleurs lier cette entropie de contact aux propriétés informationnelles des signaux qui transitent à travers le contact, la rendant accessible à la mesure
The thesis is about the construction of a phenomenology of the slippery contact based on a multi- physical approach of the contact. Pressing us on an experimental characterization very rich in the slippery electric contact, we built a theoretical model (of probability nature) and digital technology resulting among others in the evaluation of the quality of the contact through diverse quality index combining the relevant sizes of the contact, quite accessible to the measure. The model takes into account, besides the mechanics of the contact, the determinist and random components (profiles of roughness) of the geometry of surfaces involvements. The development of the digital model can be made according to two very different strategies. The first one joins characteristics of previous reference models (Greenwood-Williamson). The second offer the additional benefit of a study of the performances of the contact according to the nature of materials. Of our statistical model emerges a new concept, the entropy of contact, so called because of its big similarity with the usual entropy. Appearing as a functional of the state of surface (geometry, chemical unhomogeneity), this size presents a big sensibility in the conditions of contact such as the speed of sliding and the strength of tackle of the contact, influencing directly the transfer of electric signals through the contact. It so opens the double perspective of a thermodynamics of the slippery contact and the optimization

Singh, Akash. "An intelligent user interface model for contact centre operations". Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/d1011399.

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Contact Centres (CCs) are at the forefront of interaction between an organisation and its customers. Currently, 17 percent of all inbound calls are not resolved on the first call by the first agent attending to that call. This is due to the inability of the contact centre agents (CCAs) to diagnose customer queries and find adequate solutions in an effective and efficient manner. The aim of this research is to develop an intelligent user interface (IUI) model to support and improve CC operations. A literature review of existing IUI architectures, modelbased design and existing CC software together with a field study of CCs has resulted in the design of an IUI model for CCs. The proposed IUI model is described in terms of its architecture, component-level design and interface design. An IUI prototype has been developed as a proof of concept of the proposed IUI model. The IUI prototype was evaluated in order to determine to what extent it supports problem identification and query resolution. User testing, incorporating the use of eye tracking and a post-test questionnaire, was used in order to determine the usability and usefulness of the prototype. The results of this evaluation show that the users were highly satisfied with the task support and query resolution assistance provided by the IUI prototype. This research resulted in the design of an IUI model for the domain of CCs. This model can be used to assist the development of CC applications incorporating IUIs. Use of the proposed IUI model is expected to support and enhance the effectiveness and efficiency of CC operations. Further research is needed to conduct a longitudinal study to determine the impact of IUIs in the CC domain.

Nouira, Dorra. "Non-linear interactions between US waves and contact interface". Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0262.

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Les dernières décennies ont été marquées par un intérêt accru pour les non-linéarités dues aux défauts localisés dans les solides (les fissures fermées par exemple) et aux interfaces de contact en général. En conséquence, un certain nombre de méthodes non-linéaires ont été développés pour la détection de ces défauts et caractérisation des interfaces de contact. Cependant, la compréhension des mécanismes physiques liés aux non-linéarités due contact reste limitée. Dans ce cadre, ce travail de thèse vise à étudier l'interaction non-linéaire entre une onde et une interface tout en intégrant plusieurs mécanismes liés au contact, afin de proposer, à terme, une méthode CND efficace pour la caractérisation des interfaces. L'étude de l'évolution du second harmonique pour caractériser ce type de défauts localisés et plus généralement les interfaces de contact sera au coeur de ce travail.L'interaction non-linéaire entre une onde longitudinale et une interface de contact est modélisée en combinant deux approches. L'une est basée sur des méthodes acoustiques et utilisée en traction, tandis que l'autre est basée sur l’analyse vibratoire structurelle et utilisée en compression. La première consiste à modéliser le contact avec une loi RCCM. L'étude propose une analyse détaillée du comportement de l'interface en traction tout en intégrant l'adhérence. Elle permet d'identifier les paramètres clés qui régissent la signature non-linéaire de la loi RCCM et ainsi permet de mieux comprendre la physique derrière cette interaction non-linéaire. La deuxième méthode, utilisée en compression, est basée sur un modèle de rigidité d'interface non-linéaire où la rigidité d'interface est décrite en fonction de la pression de contact nominale. L'étude consiste en une analyse numérique et expérimentale complémentaires de la composante non-linéaire de la réponse dynamique du système due à la présence d'interface de contact. Elle montre que la tendance de la rigidité à faibles pressions a un effet majeur sur la réponse non-linéaire des systèmes avec des interfaces de contact. Enfin, les lois de contact proposées en compression et traction sont combinées en une seule loi pour permettre une meilleure corrélation entre les différents mécanismes de contact en compression et en traction et donc une meilleure caractérisation de la réponse non-linéaire du système. Les résultats numériques sont prometteurs en vue de la caractérisation d'interfaces de contact à partir de la réponse non-linéaire du système excité par une source extérieure et applicables à la détection non-destructive de l’endommagement
The past decades have been marked by a significant increase in research interest in nonlinearities in cracked solids. As a result a number of different nonlinear methods have been developed for damage detection. However, there still limited understanding of physical mechanisms related to the various nonlinearities due to contacts. This thesis is addressed to study the nonlinear interaction between a wave and an interface while taking into account adhesion, in order to, eventually, propose an efficient NDT method for characterization of contact interfaces. The study of the second-harmonic evolution to characterize the damage will be the focus of this work. The nonlinear interaction between a longitudinal wave and a contact interface is considered in one-dimensional medium by using the Finite Elements method.Numerically, the contact interface is modelled by combining two approaches. One is based on acoustic methods and used in traction, while the other one is based on vibration methods and used in compression. The first one, consists in modelling the contact with an RCCM law. The study propose a detailed analysis on the interface behaviour in traction while taking into account the adhesion. It allows identifying the key parameters that govern the nonlinear signature of the RCCM contact law and so better understanding the interaction between a compression wave and a contact interface that exhibits adhesion in traction. The second one, used in compression, is based on a nonlinear interface stiffness model where the stiffness property of the contact interface is described as a function of the nominal contact pressure. The study consists in a complementary numerical and experimental analysis of nonlinear vibrational response due to the contact interface. It shows that the stiffness-pressure trend at lower pressures has a major effect on the nonlinear response of systems with contact interfaces.Finally, in order to exploit the proposed contact law defined in compression and traction, a strategy to identify the interface parameters during the interaction between a wave and an interface is proposed. The numerical results are promising in view of the characterization of contact interfaces

MOISELLO, ELISABETTA. "Integrated Interface Circuits for MEMS Contact-less Temperature Sensors". Doctoral thesis, Università degli studi di Pavia, 2020. http://hdl.handle.net/11571/1370177.

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Thermal sensors, exploiting the relation between the thermal radiation emitted by an object and its temperature, as expressed by the Stefan-Boltzmann law, allow realizing contact-less temperature measurements, required in a wide range of applications, ranging from fever measurements to presence detection for security and climate control systems. With the advent of smart homes and Internet of Things (IoT) and the wide spreading of mobile and wearable devices, the need for low-cost low-power thermal sensors has arisen, therefore moving the focus of the research away from standard bolometers and pyroelectric detectors and towards uncooled infrared (IR) sensors solutions that can be easily integrated. Bolometers and pyroelectric detectors, which are the main types of thermal sensors found nowadays on the market, in fact, do not comply with the low-cost and easy integration specifications. Integration of thermal sensors is possible through Micro-Electro Mechanical Systems (MEMS) technology, which allows combining on the same substrate or chip both electrical and mechanical structures with dimensions in the micro-meter range, thus providing structures with high thermal isolation and low thermal mass. The micromachining processes that are required to thermally isolate the sensing element from the substrate are versatile and include anisotropic wet etching, dry and wet etching, electrochemical etch stop, or the use of silicon-on-insulator (SOI). In this scenario, STMicroelectronics has fabricated two different novel thermal sensors, which fulfill the low-cost low-power specifications for smart homes, IoT and mobile and wearable devices, while also being compatible with CMOS processes and thus easily integrated: a polysilicon thermopile and a micromachined CMOS transistor, from now on referred to as TMOS. During my Ph.D. activity I was involved in a cooperation between the STMicroelectronics Analog MEMS and Sensors R&D group and the University of Pavia, that led to the design of two readout circuits specifically tailored on the sensors characteristics, one for the thermopile sensor and one for the TMOS (developed by the Technion-Israel Institute of Technology), which were integrated in two test-chip prototypes and thoroughly characterized through measurements as stand-alone devices and as a system with the sensor they were designed for.
Thermal sensors, exploiting the relation between the thermal radiation emitted by an object and its temperature, as expressed by the Stefan-Boltzmann law, allow realizing contact-less temperature measurements, required in a wide range of applications, ranging from fever measurements to presence detection for security and climate control systems. With the advent of smart homes and Internet of Things (IoT) and the wide spreading of mobile and wearable devices, the need for low-cost low-power thermal sensors has arisen, therefore moving the focus of the research away from standard bolometers and pyroelectric detectors and towards uncooled infrared (IR) sensors solutions that can be easily integrated. Bolometers and pyroelectric detectors, which are the main types of thermal sensors found nowadays on the market, in fact, do not comply with the low-cost and easy integration specifications. Integration of thermal sensors is possible through Micro-Electro Mechanical Systems (MEMS) technology, which allows combining on the same substrate or chip both electrical and mechanical structures with dimensions in the micro-meter range, thus providing structures with high thermal isolation and low thermal mass. The micromachining processes that are required to thermally isolate the sensing element from the substrate are versatile and include anisotropic wet etching, dry and wet etching, electrochemical etch stop, or the use of silicon-on-insulator (SOI). In this scenario, STMicroelectronics has fabricated two different novel thermal sensors, which fulfill the low-cost low-power specifications for smart homes, IoT and mobile and wearable devices, while also being compatible with CMOS processes and thus easily integrated: a polysilicon thermopile and a micromachined CMOS transistor, from now on referred to as TMOS. During my Ph.D. activity I was involved in a cooperation between the STMicroelectronics Analog MEMS and Sensors R&D group and the University of Pavia, that led to the design of two readout circuits specifically tailored on the sensors characteristics, one for the thermopile sensor and one for the TMOS (developed by the Technion-Israel Institute of Technology), which were integrated in two test-chip prototypes and thoroughly characterized through measurements as stand-alone devices and as a system with the sensor they were designed for.

Sankar, Gopal Ravi. "An investigation into a natural language interface for contact centers". Thesis, Nelson Mandela Metropolitan University, 2009. http://hdl.handle.net/10948/890.

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Contact centres are the first point of contact between a company and a customer after the purchase of a product or service. These centres make use of contact centre agents to service customer queries. In the past contact centres hired as many agents as they could in order to service customers, which have led to an increase in personnel costs causing contact centres to become costly to run. Automation techniques were introduced to decrease personnel costs and one such technique is the Interactive Voice Response (IVR). The usability of IVR systems is, however, dismal. Customers would rather speak to a contact centre agent than navigate through the menu structure found in these systems. The menu structure has come under scrutiny because it is difficult to use and navigate, is often not aligned to caller usage patterns, and the menu options are long and vague. This research investigated whether a Natural Language Interface (NLI) could alleviate the problems inherent to IVR. NLIs, however, come with their own disadvantages of which the main ones are ambiguity and the loss of context of a conversation. Two prototypes were implemented, one of which resembled an IVR and the other an NLI (using ALICE concepts). An evaluation of two prototypes confirmed the advantages and disadvantages of these concepts in accordance to theory. A Hybrid prototype was proposed with the aid of two models. The model which proposed an NLI using a rule base was chosen for implementation. The Hybrid prototype was then evaluated against the NLI and IVR prototypes to deduce which prototype was the most effective, efficient and satisfying. The evaluation through the aid of descriptive and inferential statistics showed that the Hybrid prototype was the most usable prototype. The evaluation of the Hybrid prototype confirmed that a Hybrid approach could limit the shortcomings of IVR through the elimination of the menu structure found in these systems, thereby allowing users to state their queries in natural language. The incorporated rule base provided the Hybrid system with long term memory, eliminating one of the main disadvantages of NLIs.

Rai, Yugal. "In-situ interface chemical characterisation of a boundary lubricated contact". Thesis, University of Leeds, 2015. http://etheses.whiterose.ac.uk/12191/.

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An increasing demand for improved fuel efficiency and more reliable automotive engines has seen a number of approaches made to further improve the tribological performance in automotive engine parts. Engine oil lubricants extend the life of the moving parts operating under different conditions and also preventing any damages to these parts. However, although its applications are beneficial towards the moving parts, the environmental implications of these lubricants are somewhat harmful, leading to stricter regulations against its emissions. Strict emission requirements have led to a greater interest in understanding the tribological performance of these lubricant additives. Hence, in order to develop more environmentally friendly additives, it is necessary to understand the tribochemical mechanism that occur at the lubricated systems. However, to date despite considerable efforts, a model to predict friction coefficient is only limited to elastohydrodynamic and hydrodynamic lubrication systems. Under boundary and mixed lubrication conditions, the friction and wear behaviour of the tribological system are characterised by the surface asperities of real contact and with the formation of thin surface films. Thus, sophisticated and reliable experimental techniques are required to investigate and assess the tribological systems under this conditions. In-situ approaches can greatly enhance our understanding on the progressive developments between the contacting interfaces, including the detailed chemical, structural and physical interactions governing friction and wear. The research focuses on developing a methodology for in situ and real time boundary lubricated surface optical and chemical characterisation with the aid of Raman Spectroscopy. The techniques are developed with the lubricant additive of Molybdenum Dialkyldithiocarbamate (MoDTC) and used to experimentally evaluate the interface phenomena occurring in a bench tribometer. MoDTC under defined tribological conditions forms MoS2 tribofilms which reduces friction. Surface analytical methodology of ex-situ and in-situ analysis is applied for the lubricant additive to understand the tribochemical process occurring at the tribological contacts.

Gonzalez, Franck. "Contributions au développement d'une interface haptique à contacts intermittents". Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066068/document.

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Les interfaces haptiques permettent à un opérateur d'interagir avec un environnement virtuel ou distant via le sens du toucher.La majorité des interfaces de l'état de l'art restent au contact de l’utilisateur pendant toute la durée de la manipulation. La liaison permanente entre le robot et l’opérateur nuit à la qualité de l’interaction, notamment en réduisant la transparence en espace libre. Ce problème est d’autant plus prégnant dans le cadre des interfaces haptiques dextres.Cette thèse a pour objectif d'étudier la possibilité d'augmenter la transparence et le réalisme de l'interaction à travers le développement d’interfaces à contacts intermittents. Il s’agit de déconnecter le robot de l'utilisateur lorsqu’aucun contact avec l’environnement n’est nécessaire. Un état de l’art des performances de la manipulation humaine, des interfaces haptiques dextres ainsi que des travaux relatifs au contact intermittent, est d’abord présenté. Un effecteur plan pour le contact intermittent est ensuite conçu. Il est installé à l’extrémité distale d'une interface haptique et plusieurs solutions sont envisagées pour sa loi de commande. Les performances de dix utilisateurs sont comparées dans le cadre d'une tâche de détection de contact en utilisant d'une part l'effecteur adapté au contact intermittent, d'autre part une interface haptique classique. L'élaboration d'une interface permettant une interaction plus naturelle avec l'environnement est ensuite initiée par l'élaboration d'une méthodologie de choix des zones de contact de la main à prendre en compte dans la conception d'une interface haptique. Des perspectives sont finalement données quant à l'extension de ces résultats à une interface haptique dextre à contacts intermittents
Haptic interfaces allow an operator to interact with a virtual environment through the sense of touch. Nowadays, most existing interfaces are mechanically connected to the user's hand throughout the simulation. Therefore he or she interacts with the virtual environment by means of a handle. Thus the interaction is neither natural nor intuitive, and the permanent connection between the robot and the operator is the source of perturbations which prevent the interaction from being perfectly transparent and realistic. The goal of this study is to increase transparency as much as possible by disconnecting the robot from the user when s/he is not in contact with the virtual environment, through the design of a dexterous haptic interface allowing for a more natural interaction than with a classical interface taking into account only one contact point. A state-of-the-art of dexterous haptic interfaces and another for intermittent contact devices are first gathered, and the human performances that should be taken into account for the design of a dexterous haptic interface are analysed. A bidirectional end-effector for intermittent contact is then devised. It is set up at the tip of a haptic interface and several solutions are tested for its control. The performances of six users are compared on the context of a contact detection task, first using the intermittent contact end-effector, then using a classical haptic device. A methodology for the choice of the hand contact areas that should be taken into account in the design of a dexterous haptic interface to enhance the naturalness of the interaction is proposed. Finally, some perspectives are given as for the extension of this study for the design of a dexterous encounter-type haptic interface

Più fonti

Libri sul tema "Interface de contact":

Kikuchi, Masato. A non-contact computer interface. Manchester: UMIST, 1994.

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Olofsson, U., e R. Lewis. Wheel-rail interface handbook. Boca Raton, FL: CRC Press, 2009.

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Vladimír, Kolář. Contact stress and settlement in the structure-soil interface. Prague: Academia, 1991.

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Association, International Heavy Haul. Guidelines to best practices for heavy haul railway operations: Wheel and rail interface issues. Virginia Beach, Va: International Heavy Haul Association, 2001.

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McKay, Iain. The strategic desktop: Usability engineering for the contact centre workstation. Edinburgh: Spotlight, 2003.

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Carvalho, Ana Maria, e Patrícia Matos Amaral. Portuguese-Spanish interfaces: Diachrony, synchrony, and contact. Amsterdam: John Benjamins Publishing Company, 2014.

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Mitchell, Richard. Design by contract, by example. Boston, Mass: Addison Wesley, 2002.

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David, Riha, Southwest Research Institute e United States. National Aeronautics and Space Administration., a cura di. NESSUS/NASTRAN interface: Final report, NASA contract NAS8-39797, SwRI project 06-7212. [Washington, DC: National Aeronautics and Space Administration, 1996.

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Khatamian, D. Hydrogen traps in the oxide/alloy interface region of Zr-Nb alloys. Chalk River, Ont: Reactor Materials Research Branch, Chalk River Laboratories, 1995.

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Gregory, Jerkiewicz, Feliu Juan M, Popov Branko N, Electrochemical Society Meeting, Electrochemical Society. Physical Electrochemistry Division. e International Symposium on Hydrogen Surfaces and Interfaces (2000 : Toronto, Ont.), a cura di. Hydrogen at surface and interfaces: Proceedings of the international symposium. Pennington, NJ: Electrochemical Society, Inc., 2000.

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Capitoli di libri sul tema "Interface de contact":

Tadros, Tharwat. "Contact Angle". In Encyclopedia of Colloid and Interface Science, 147. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-20665-8_55.

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Collins, W. D., M. S. Khalil, S. Quegan, D. Smith e D. A. W. Taylor. "Interface Pressures in Contact Zones". In European Consortium for Mathematics in Industry, 121–24. Wiesbaden: Vieweg+Teubner Verlag, 1992. http://dx.doi.org/10.1007/978-3-663-09834-8_20.

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Wang, Yansong. "Friction in Conformal Contact Interface". In Encyclopedia of Tribology, 1311–15. Boston, MA: Springer US, 2013. http://dx.doi.org/10.1007/978-0-387-92897-5_31.

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Langbein, Dieter. "Interface Tension and Contact Angle". In Springer Tracts in Modern Physics, 21–39. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/3-540-45267-2_2.

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Fitzgerald, R. H. "Calcar/Collar Contact in Cemented Total Hip Arthroplasty". In Implant Bone Interface, 147–48. London: Springer London, 1990. http://dx.doi.org/10.1007/978-1-4471-1811-4_20.

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Laursen, Tod A. "Tribological Complexity in Interface Constitutive Models". In Computational Contact and Impact Mechanics, 211–94. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-662-04864-1_6.

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Sessarego, Sandro. "Contact-driven restructuring at the interface". In Interface-Driven Phenomena in Spanish, 192–220. 1. | New York : Routledge, 2020. | Series: Routledge studies in Hispanic and Lusophone linguistics: Routledge, 2020. http://dx.doi.org/10.4324/9781003006855-10.

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Pastor, Elsa. "Direct Flame Contact". In Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires, 1–7. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-51727-8_64-1.

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Pastor, Elsa. "Direct Flame Contact". In Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires, 221–26. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-319-52090-2_64.

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Wang, Q. Jane, e Shangwu Xiong. "Elasticity for Closely Conformal Contact Interface". In Encyclopedia of Tribology, 859–66. Boston, MA: Springer US, 2013. http://dx.doi.org/10.1007/978-0-387-92897-5_25.

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Atti di convegni sul tema "Interface de contact":

Mootheri, Vivek, Albert Minj, Goutham Arutchelvan, Alessandra Leonhardt, Inge Asselberghs, Marc Heyns, Iuliana Radu e Dennis Lin. "Contact Interface Characterization of Graphene contacted MoS2 FETs". In 2021 IEEE International Interconnect Technology Conference (IITC). IEEE, 2021. http://dx.doi.org/10.1109/iitc51362.2021.9537337.

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Caven, R. W., e J. Jalali. "Predicting the contact resistance distribution of electrical contacts by modeling the contact interface". In Electrical Contacts - 1991 Proceedings of the Thirty-Seventh IEEE HOLM Conference on Electrical Contacts. IEEE, 1991. http://dx.doi.org/10.1109/holm.1991.170807.

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Max Kiessling, Jonathan, Thomas Maier, Simon Wiesenfarth e Stephan Mayer. "User-centered design of an adaptively morphing human-machine interface". In 14th International Conference on Applied Human Factors and Ergonomics (AHFE 2023). AHFE International, 2023. http://dx.doi.org/10.54941/ahfe1003182.

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Adaptively morphing (shape changing) human hand-machine interfaces aim at increasing usability for various users, especially older walking-aid users with impaired hands. This paper introduces such an interface design for a five-finger hand-handle contact consisting of machined and additive manufactured components. Functionality is achieved via a granulate-filled flexible shell and pneumatic-actuated jamming. The interface is tested in a realistic use context experiment. The results contain positive subjective comfort evaluation and a digital workflow for design parameter analysis. Further design iterations considering these parameters are proposed.

Tong, Tao, Yang Zhao, Lance Delzeit, Ali Kashani e Arun Majumdar. "Multiwalled Carbon Nanotube/Nanofiber Arrays as Conductive and Dry Adhesive Interface Materials". In ASME 2004 3rd Integrated Nanosystems Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/nano2004-46013.

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We demonstrate the possibility of making conductive and dry adhesive interfaces between multiwalled carbon nano-tube (MWNT) and nanofiber (MWNF) arrays grown by chemical vapor deposition with transition-metal as catalyst on silicon substrates. The maximum observed adhesion force between MWNT and MWNF surfaces is 3.5 mN for an apparent contact area of 2 mm by 4 mm. The minimum contact resistance measured at the same time is ∼20 Ω. Contact resistances of MWNT-MWNT and MWNT-gold interfaces were also measured as pressure forces around several milli-Newton were applied at the interface. The resulting minimum contact resistances are on the same order but with considerable variation from sample to sample. For MWNT-MWNT contacts, a minimum contact resistance of ∼ 1 Ω is observed for a contact area of 2 mm by 1 mm. The relatively high contact resistances, considering the area density of the nanotubes, might be explained by the high cross-tube resistances at the contact interfaces and limited inter-penetration of the nanotube arrays.

Schwingshackl, C. W., E. P. Petrov e D. J. Ewins. "Validation of Test Rig Measurements and Prediction Tools for Friction Interface Modelling". In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-23274.

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The modelling of friction contact interfaces in structural dynamics attracts much interest in the gas turbine industry. In order to obtain reliable predictions of typical friction interfaces, such as encountered in under platform dampers or blade roots, accurate characteristics of friction interfaces must be provided to the analysis. It must be ensured that a sufficient number of parameters are provided, characterising all aspects of the friction contact, that the values are measured accurately, and that the contact parameters are interpreted and used correctly in the numerical modelling of the contact interfaces. This investigation demonstrates that measured friction coefficient and tangential contact stiffness are sufficient to reproduce the experimental friction interface behaviour and that these two parameters can be measured reliably in the available test rig. In combination with fine nonlinear interface meshes and accurate contact pressure representations, the measured interface behaviour of stick, micro- and macroslip is reproduced with good accuracy. The capability of modelling the microslip behaviour for the contact interface by a multitude of friction contact elements is explored and the effect of the normal stress distribution over the contact area on the microslip is studied.

Malucci, Robert D. "Current Redistribution across an Aging Contact Interface". In 2012 IEEE 58th Holm Conference on Electrical Contacts (Holm 2012). IEEE, 2012. http://dx.doi.org/10.1109/holm.2012.6336578.

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Smith, P. W. "Head/media interface design for contact recording". In IEEE International Magnetics Conference. IEEE, 1999. http://dx.doi.org/10.1109/intmag.1999.837390.

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Myers, M., M. Leidner e H. Schmidt. "Effect of Contact Parameters on Current Density Distribution in a Contact Interface". In 2011 IEEE 57th Holm Conference on Electrical Contacts (Holm 2011). IEEE, 2011. http://dx.doi.org/10.1109/holm.2011.6034783.

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Huang, Qiu-Hong, Yu-Bo Liu, Li-Ling Feng, Min Zhao e Zong-Ming Qiu. "Ultrasonic Detecting Method of Mechanical Interface Contact Distribution". In 2016 Sixth International Conference on Instrumentation & Measurement, Computer, Communication and Control (IMCCC). IEEE, 2016. http://dx.doi.org/10.1109/imccc.2016.94.

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Wise, Robert A., e Paul M. McElroy. "Interface Contact Coefficients Used in Thermal Engineering Analyses". In International Conference On Environmental Systems. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1997. http://dx.doi.org/10.4271/972383.

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Rapporti di organizzazioni sul tema "Interface de contact":

McMichael, L. Contact Interface Verification for DYNA3D Scenario 1: Basic Contact. Office of Scientific and Technical Information (OSTI), maggio 2006. http://dx.doi.org/10.2172/898003.

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McMichael, L. Contact Interface Verification for DYNA3D Scenario 2: Multi-Surface Contact. Office of Scientific and Technical Information (OSTI), maggio 2006. http://dx.doi.org/10.2172/898011.

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Khounsary, A. M., D. Chojnowski, L. Assoufid e W. M. Worek. Thermal contact resistance across a copper-silicon interface. Office of Scientific and Technical Information (OSTI), ottobre 1997. http://dx.doi.org/10.2172/554855.

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Phelan, P. E., R. C. Niemann e T. H. Nicol. Thermal contact resistance for a CU/G-10CR interface in a cylindrical geometry. Office of Scientific and Technical Information (OSTI), luglio 1996. http://dx.doi.org/10.2172/285441.

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Lever, James, Susan Taylor, Arnold Song, Zoe Courville, Ross Lieblappen e Jason Weale. The mechanics of snow friction as revealed by micro-scale interface observations. Engineer Research and Development Center (U.S.), dicembre 2021. http://dx.doi.org/10.21079/11681/42761.

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The mechanics of snow friction are central to competitive skiing, safe winter driving and efficient polar sleds. For nearly 80 years, prevailing theory has postulated that self-lubrication accounts for low kinetic friction on snow: dry-contact sliding warms snow grains to the melting point, and further sliding produces meltwater layers that lubricate the interface. We sought to verify that self-lubrication occurs at the grain scale and to quantify the evolution of real contact area to aid modeling. We used high-resolution (15 μm) infrared thermography to observe the warming of stationary snow under a rotating polyethylene slider. Surprisingly, we did not observe melting at contacting snow grains despite low friction values. In some cases, slider shear failed inter-granular bonds and produced widespread snow movement with no persistent contacts to melt (μ < 0.03). When the snow grains did not move and persistent contacts evolved, the slider abraded rather than melted the grains at low resistance (μ < 0.05). Optical microscopy revealed that the abraded particles deposited in air pockets between grains and thereby carried heat away from the interface, a process not included in current models. Overall, our results challenge whether self-lubrication is indeed the dominant mechanism underlying low snow kinetic friction.

Lever, James, Susan Taylor, Garrett Hoch e Charles Daghlian. Evidence that abrasion can govern snow kinetic friction. Engineer Research and Development Center (U.S.), dicembre 2021. http://dx.doi.org/10.21079/11681/42646.

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The long-accepted theory to explain why snow is slippery postulates self-lubrication: frictional heat from sliding melts and thereby lubricates the contacting snow grains. We recently published micro-scale interface observations that contradicted this explanation: contacting snow grains abraded and did not melt under a polyethylene slider, despite low friction values. Here we provide additional observational and theoretical evidence that abrasion can govern snow kinetic friction. We obtained coordinated infrared, visible-light and scanning-electron micrographs that confirm that the evolving shapes observed during our tribometer tests are contacting snow grains polished by abrasion, and that the wear particles can sinter together and fill the adjacent pore spaces. Furthermore, dry-contact abrasive wear reasonably predicts the evolution of snow-slider contact area and sliding-heat-source theory confirms that contact temperatures would not reach 0°C during our tribometer tests. Importantly, published measurements of interface temperatures also indicate that melting did not occur during field tests on sleds and skis. Although prevailing theory anticipates a transition from dry to lubricated contact along a slider, we suggest that dry-contact abrasion and heat flow can prevent this transition from occurring for snow-friction scenarios of practical interest.

Mozley, Peter, James Evans e Thomas Dewers. Area of Interest 1, CO₂ at the Interface: Nature and Dynamics of the Reservoir/Caprock Contact and Implications for Carbon Storage Performance. Office of Scientific and Technical Information (OSTI), ottobre 2014. http://dx.doi.org/10.2172/1177773.

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Blum, L. Contact Theorems for Rough Interfaces. Fort Belvoir, VA: Defense Technical Information Center, aprile 1994. http://dx.doi.org/10.21236/ada282988.

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Lever, James, Emily Asenath-Smith, Susan Taylor e Austin Lines. Assessing the mechanisms thought to govern ice and snow friction and their interplay with substrate brittle behavior. Engineer Research and Development Center (U.S.), dicembre 2021. http://dx.doi.org/10.21079/1168142742.

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Sliding friction on ice and snow is characteristically low at temperatures common on Earth’s surface. This slipperiness underlies efficient sleds, winter sports, and the need for specialized tires. Friction can also play micro-mechanical role affecting ice compressive and crushing strengths. Researchers have proposed several mechanisms thought to govern ice and snow friction, but directly validating the underlying mechanics has been difficult. This may be changing, as instruments capable of micro-scale measurements and imaging are now being brought to bear on friction studies. Nevertheless, given the broad regimes of practical interest (interaction length, temperature, speed, pressure, slider properties, etc.), it may be unrealistic to expect that a single mechanism accounts for why ice and snow are slippery. Because bulk ice, and the ice grains that constitute snow, are solids near their melting point at terrestrial temperatures, most research has focused on whether a lubricating water film forms at the interface with a slider. However, ice is extremely brittle, and dry-contact abrasion and wear at the front of sliders could prevent or delay a transition to lubricated contact. Also, water is a poor lubricant, and lubricating films thick enough to separate surface asperities may not form for many systems of interest. This article aims to assess our knowledge of the mechanics underlying ice and snow friction.

Dahlgren, Tamara Lynn. Performance-Driven Interface Contract Enforcement for Scientific Components. Office of Scientific and Technical Information (OSTI), gennaio 2008. http://dx.doi.org/10.2172/932393.

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