Relevant bibliographies by topics / Process modelization

Academic literature on the topic 'Process modelization'

Author: Grafiati
Published: 1 June 2024

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Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Journal articles on the topic "Process modelization":

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Posada Rodríguez, M. J., I. J. Suárez Rodríguez, and J. Sáiz de Ayala. "Sintering process burn-through point modelization." Revue de Métallurgie 106, no. 6 (June 2009): 225–33. http://dx.doi.org/10.1051/metal/2009038.

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Stroe, M. C., and J. M. Crolet. "Modelization of osteoporosis process: a possible explanation." Computer Methods in Biomechanics and Biomedical Engineering 14, sup1 (August 2011): 177–79. http://dx.doi.org/10.1080/10255842.2011.594711.

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Zanoli, Silvia Maria, Crescenzo Pepe, Elena Moscoloni, and Giacomo Astolfi. "Data Analysis and Modelling of Billets Features in Steel Industry." Sensors 22, no. 19 (September 27, 2022): 7333. http://dx.doi.org/10.3390/s22197333.

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This study proposes a data analysis and modelization method for the rolling mill process of billets in steel plants. By exploiting rolling mill signals and advanced data processing algorithms, a reliable billet tracking system is designed, which tracks each workpiece from the furnace entrance to the rolling mill stands’ exit area. Based on the stored information, two problems are addressed: the data analysis of the temperature sensors (a thermal imaging camera and pyrometers) and the current that is related to the rolling mill stands’ absorption, and subsequently, a mathematical modelization of the billets’ temperature along their path in the rolling mill is produced. The data analysis suggested that we should perform hardware modifications: the thermal imaging camera was repositioned to avoid the effect of scale formation on the temperature measurements. The modelization phase provided the basis for future control and/or diagnosis applications that will exploit a temperature decay model.
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Boly, V., L. Morel, and J. Renaud. "A Functional Modelization of Innovation Process: Results of an Expert Inquiry." IFAC Proceedings Volumes 33, no. 12 (June 2000): 221–24. http://dx.doi.org/10.1016/s1474-6670(17)37313-5.

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Chevalier, Damien, Pierre Cezard, Laurent Langlois, and Régis Bigot. "Modelization of the Rolling Mill with a FE Code." Key Engineering Materials 651-653 (July 2015): 291–96. http://dx.doi.org/10.4028/www.scientific.net/kem.651-653.291.

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To reduce production costs and to improve performances of hot rolled products, it is necessary to optimize the production line. The rolling mill is one of the major factors which affect the internal quality. In fact the process tends to reduce the size of defects during the strain. The production line consisting of 24 stands has been modeled with a commercial FE-code FORGE®. First, a model has been developed and adjusted according to industrial data. Then a parametric study was carried out in order to estimate the influence of the process parameters on the internal quality of the rolled material.
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MURAJI, Yutaro. "CREATING ARCHITECTURAL DESIGN AS COMMON RESOURCE AND MODELIZATION OF ITS DEVELOPMENT PROCESS." AIJ Journal of Technology and Design 27, no. 65 (February 20, 2021): 406–11. http://dx.doi.org/10.3130/aijt.27.406.

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Papageorgiou, Loula, Kutaiba Alhaj Hussen, Sandrine Thouroude, Elisabeth Mbemba, Héléne Cost, Laurent Garderet, Ismail Elalamy, et al. "Modelization of Blood-Borne Hypercoagulability in Myeloma: A Tissue-Factor-Bearing Microparticle-Driven Process." TH Open 03, no. 04 (October 2019): e340-e347. http://dx.doi.org/10.1055/s-0039-1700885.

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Abstract Introduction Hypercoagulability is a common blood alteration in newly diagnosed chemotherapy naïve patients with multiple myeloma. The identification of the procoagulant potential of cancer cells, which is principally related to tissue factor (TF) expression, attracts particular interest. The mechanisms by which myeloma plasma cells (MPCs) activate blood coagulation have been poorly investigated. Aim To identify the principal actors related with MPCs that boost thrombin generation (TG). Methods TF and annexin V expression by MPCs and MPC-derived microparticles (MPC-dMPs) was analyzed by flow cytometry. TF activity (TFa) and TF gene expression were also determined. TG in the presence of MPCs or MPC-dMPs was assessed with the calibrated automated thrombogram assay (CAT) in normal human PPP and in plasma depleted of factor VII or XII. TG was also assessed in plasma spiked with MPCs and MPC-dMPs. Results MPC-dMPs expressed approximately twofold higher levels of TF as compared with MPCs. The TFa expressed by MPC-dMPs was significantly higher compared with that expressed by MPCs. MPCs and MPC-dMPs enhanced TG of human plasma. TG was significantly higher with MPC-dMPs compared with MPCs. Conclusion MPCs indirectly induce blood-borne hypercoagulability through the release of MPC-dMPs rich in TF. Since MPCs, expressing low TFa, represent a weak procoagulant stimulus, the hypercoagulability at the microenvironment could be the resultant of MPC-dMPs rich in TF.
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Sellés, M. A., S. R. Schmid, S. Sánchez-Caballero, E. Pérez-Bernabeu, M. J. Reig, and V. J. Segui. "Theoretical Model of a Multi-Layered Polymer Coated Steel-Strip Ironing Process Using a Neural Network." Materials Science Forum 713 (February 2012): 139–44. http://dx.doi.org/10.4028/www.scientific.net/msf.713.139.

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An alternative to the traditional can manufacturing process is to use plastic laminated rolled steels as base stocks. This material consist of pre-heated steel coils that are sandwiched between one or two sheets of polymer. The heated sheets are then immediately quenched, which yields a strong bond between the layers. Such polymer-coated steels were investigated by Jaworski [1, and Sellés [, and found to be suitable for ironing with carefully controlled conditions. A novel multi-layer polymer coated steel has been developed for container applications. This material presents an interesting extension to previous research on polymer laminated steel in ironing, and offers several advantages over the previous material (Sellés [). This document shows a modelization for the ironing process (the most crucial step in can manufacturing) done by using a neural network.
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Zhang, Chao, Xiao Guang Yang, Jian Hua Zhou, and Ai Jun Huang. "Modelization and Validation of Ti-6Al-4V Alloy Material Constitutive Law for Isothermal Forging Process." Key Engineering Materials 622-623 (September 2014): 207–16. http://dx.doi.org/10.4028/www.scientific.net/kem.622-623.207.

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Isothermal forging is a near-net shape forming technology for manufacturing complex titanium alloy components. In order to characterize the workability of Ti-6Al-4V alloy during isothermal forging process, the material properties of Ti-6Al-4V alloy were investigated by isothermal compression tests under different strain rate-temperature, where the temperature range is 850~1000 °C and strain rate range is 0.001~0.05s−1. The obtained flow stress-strain data was used to develop the Arrhenius constitutive model of which material constants considered the compensation of strain. The developed constitutive model was used to simulate the isothermal forging process of Ti-6Al-4V alloy component by finite element (FE) based numerical method. The metal flow and potential defect locations were predicted by numerical simulation. Furthermore, the relevant simulation results were compared with the product in industrial workshop to demonstrate the validity of material constitutive model. Keywords: Isothermal forging; Ti-6Al-4V alloy; Hot compression test; Arrhenius constitutive model; FE analysis; Model validation;
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Massironi, Carlo. "Philip Fisher’s sense of numbers." Qualitative Research in Financial Markets 6, no. 3 (November 10, 2014): 302–31. http://dx.doi.org/10.1108/qrfm-01-2013-0004.

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Purpose – This paper aims to propose an account of the use of numbers and mathematical formulae and, more generally, of the quantitative aspects in the qualitative equity valuation model of the American investor Philip A. Fisher who is considered to be one of the fathers of the qualitative equity valuation models. Design/methodology/approach – A Conceptual analysis was conducted (Glasersfeld, 1992) of the four volumes published by Fisher between 1954 and 1980 (1958, 1960, 1975, 1980) in relation to his equity valuation process. On the basis of this analysis, a modelization of this author’s perspective on quantitative instruments was built. Findings – A modelization to use quantitative data in a qualitative equity valuation model that is sufficiently detailed and useful for an asset manager is proposed. Originality/value – What is propose is a qualitative analysis of quantitative elements in the thought of a qualitative author on the subject of equity valuation. It is believed that this paper could be of interest to all those who use or are involved in the development of qualitative models of equity valuation or business valuation. This work is also an example of how conceptual analysis – generally employed in the field of mathematics education research – can be used to build descriptive models of decision-making processes of individual investors, models designed to enable the reproduction/approximation of the conceptual operations of the investor.
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Journal articles

Dissertations / Theses on the topic "Process modelization":

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Henry, Tiphaine. "Towards trustworthy, flexible, and privacy-preserving peer-to-peer business process management systems." Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAS024.

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La technologie blockchain peut être utilisée comme outil de désintermédiation fiable pour la gestion des processus métiers inter-organisationnels. Elle assure la traçabilité de l'exécution des activités et du flux de contrôle. Cependant, assurer la confiance dans le protocole de déploiement et d'exécution, permettre la flexibilité des processus et respecter la confidentialité des données restent trois verrous à solutionner dans cet environnement.Pour résoudre les problématiques susmentionnées , nous présentons les contributions suivantes.D'abord, nous présentons un mécanisme de déploiement et d'exécution on/off-chain pour les processus chorégraphiques. Cette solution assure une séparation fiable des vues entre les participants à chaque étape du déploiement et de l'exécution des instances. Ce faisant, nous tirons parti d'un langage de modèle de processus métiers déclaratif, DCR, qui permet d'abstraire le flux de contrôle.Deuxièmement, nous proposons un mécanisme de changement d'instances de chorégraphies DCR en cours d'exécution sur la blockchain. Un changement affectant d'autres partenaires est propagé aux processus concernés via un contrat intelligent. Nous proposons également une sélection dynamique de fournisseurs de services gérée par contrat intelligent.Enfin, nous proposons deux mécanismes préservant la confidentialité des enchères et des paiements dans un contexte blockchain. Le premier mécanisme se base sur du chiffrement entièrement homomorphe. Les calculs gérés par la blockchain opèrent sur des nombres chiffrés. Le deuxième mécanisme utilise une banque et un jeton de paiement (NFT) à valeur aléatoire. Les partenaires utilisent ces jetons pour procéder à plusieurs paiements tout en préservant la confidentialité des valeurs.Nous démontrons la faisabilité de chaque contribution au travers d'un prototype et son efficacité via des expérimentations ancrées dans le domaine logistique
Blockchain technology has been introduced as a trustworthy disintermediation tool for managing cross-organizational business processes in the past decade. It ensures activities' execution traceability while enforcing the control flow agreed upon at design time with other partners.However, ensuring trust in the deployment and execution protocol, process flexibility, and data privacy remains challenging in this environment.To address these challenges, we propose the three following contributions in this manuscript.First, we design and implement an on/off-chain deployment and execution strategy for on/off-chain choreographies, which enforces a trustworthy separation of concern between participants at each step of the deployment and execution. Meanwhile, we leverage a constraint-based business model language, DCR, abstracting the control flow under a set of constraints.Second, we propose to bring control-flow flexibility to the blockchain-based business process management system through change management: a change impacting other partners is propagated to affected processes using a smart contract. We also leverage smart contracts for a dynamic selection of service providers. The system analyses service providers' performance stored as blockchain logs and dynamically decides on the allocation of a task based on the QoS outputs.Finally, we propose two mechanisms to reconcile privacy imperatives with the benefits of blockchain. The first mechanism leverages fully homomorphic encryption for blockchain-based calculations such as sealed-bid auctions. Smart contracts gather and orchestrate bid comparison, while a computation oracle carries comparisons over ciphered data. The second mechanism leverages banks as trustworthy intermediaries while secreting the payment value. Partners can use per-collaboration tokens backed by a random value to proceed to multiple payments confidentially.We demonstrate the feasibility of each contribution through an implemented prototype and its effectiveness via experiments anchored in the logistics domain
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Trouvain, Guillaume. "Evolution des outils de simulation rapide du procédé de fabrication du pneumatique avant cuisson." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22546/document.

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Ces travaux de thèse s’intéressent aux outils de simulation rapide de la fabrication d’un pneumatique. L'objectif est de prédire le mouvement et la position des éléments constitutifs du pneumatique, lors de leur mise en conformation, en prenant en compte les déformations induites par les actions mécaniques associées. Ces travaux s’appuient sur la mise en place d’un algorithme visant à modéliser le gonflement d’un outillage et la mise en place d’un modèle de déformation d’un système de formes géométriques aux caractéristiques mécaniques différentes. L'algorithme de gonflement de l’outillage se base sur la théorie des membranes inextensibles et son industrialisation est validée pour des dimensions standards de pneumatiques. La méthode Masse-Ressort est retenue pour réaliser la déformation de formes géométriques afin d’obtenir des résultats de déformation en temps réel. Dans ces travaux, cette méthode est adaptée aux matériaux d’un pneumatique à partir de travaux de caractérisations géométrique et mécanique validés par comparaison aux Éléments Finis. En conclusion, la modélisation développée permet une description à chaque étape du procédé de fabrication
This thesis deals with fast simulation tools used to manufacture of a tire. The goal is to predict the displacement and position of the components of a tire taking into account the deformations induced by the associated mechanical actions. This work is based on the implementation of an algorithm for modeling the inflation of a tool and the development of a deformation model in order to compute the deformation of geometric shapes taking into account different mechanical properties. The algorithm to model the inflation of the tool is based on the theory of inextensible membranes and its industrialization is validated for standard sizes of tires. Mass-Spring method is used to achieve the deformation of geometric shapes in order to compute deformation in real time. In this work, this method is suitable for materials of a tire from geometric and mechanical characterizations validated by comparison with FEM. To conclude, the developed modelization allows a description for each step of the manufacturing process

Books on the topic "Process modelization":

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Cardot, Hervé, and Pascal Sarda. Functional Linear Regression. Edited by Frédéric Ferraty and Yves Romain. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780199568444.013.2.

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This article presents a selected bibliography on functional linear regression (FLR) and highlights the key contributions from both applied and theoretical points of view. It first defines FLR in the case of a scalar response and shows how its modelization can also be extended to the case of a functional response. It then considers two kinds of estimation procedures for this slope parameter: projection-based estimators in which regularization is performed through dimension reduction, such as functional principal component regression, and penalized least squares estimators that take into account a penalized least squares minimization problem. The article proceeds by discussing the main asymptotic properties separating results on mean square prediction error and results on L2 estimation error. It also describes some related models, including generalized functional linear models and FLR on quantiles, and concludes with a complementary bibliography and some open problems.

Book chapters on the topic "Process modelization":

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Pottier, No¨elle. "Master equations." In Nonequilibrium Statistical Physics, 219–34. Oxford University PressOxford, 2009. http://dx.doi.org/10.1093/oso/9780199556885.003.0009.

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Abstract To begin with, we consider those physical phenomena likely to be modelized by random processes. The processes which are most commonly used for this type of modelization are the Markov processes, often called picturesquely ‘processes without memory’. A Markov process is governed by its transition probabilities, which allow us, step by step, to determine its evolution from its initial distribution. The transition probabilities of a Markov process obey a non-linear functional equation, the Chapman– Kolmogorov equation. If we have independent information about the behavior of the transition probabilities over short time intervals, we can deduce from the Chapman– Kolmogorov equation a linear equation, called the master equation, describing the evolution of the transition probabilities over much longer time intervals.
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Catelani, Daniele. "From the Digital-Twin to the Cyber Physical System Using Integrated Multidisciplinary Simulation." In Advances in Systems Analysis, Software Engineering, and High Performance Computing, 18–39. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-6721-0.ch002.

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Simulation has been a competitive differentiator for engineering-driven businesses, available at all stages of the development process and lifecycle, used by the various domains within an organization, not necessarily simulation experts. It requires discipline integration, scalability, reduced-order model, and democratization. The concept of digital transformation involves new approaches for data and lifecycle management, the understanding of the digital thread, digital twin, predictive and cognitive capabilities, including improvement of model complexity, integration of physics, increase of knowledge. These trends require bringing the physical and virtual worlds closer together and also the adoption of cyber-physical model at all stages of design, production, and operation. To overcome the drawback of simulation and the need to balance the computational effort with accuracy and efficiency, new modelization strategies are adopted with ML and AI, which use a combination of virtual and physical data for training ROM, with an order of magnitude faster than the multiphysics one.
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Bougherra, Souhaib, and Mourad Belgasmia. "Optimization of Soil Structure Effect by the Addition of Dashpots in Substratum Modelization." In Optimization of Design for Better Structural Capacity, 186–200. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-7059-2.ch007.

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Soil structure interaction can significantly affect the behavior of buildings subjected to seismic attacks, wind excitation, and other dynamic loading types. Different researches were developed in the last decade demonstrating the importance of taking account of soil properties and its effect in changing the behavior of the structures. It is common practice to analyze the structures assuming a fixed base, but this approach is not appropriate for the reason that neglecting the soil parameters such as the stiffness and the damping affect the behavior of the structure. Therefore, the nonlinear static approach provided the nonlinear response behavior of a structure for different types of soil. In this chapter, the authors will discuss some proposed methods in taking account of soil-structure interaction that must be considered from the very beginning of the design process and its impact on the structural behavior optimization by adding springs and dashpots to reproduce the soil behavior.

Conference papers on the topic "Process modelization":

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BIZOT, A., J. FERREIRA, and G. LENGELLE. "Modelization of the ignition process of homogeneous propellants." In 21st Joint Propulsion Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1985. http://dx.doi.org/10.2514/6.1985-1178.

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Cattelino, Pier Michele, Corrado Licata, and Luigi Rèpaci. "Recent Development in Process Control for Aluminum Cold Rolling: Features of the Fata Hunter’s hSystem®." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-0650.

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Abstract Aim of the present paper is to highlight Fata Hunter’s hSystem®, emphasizing its self adaptive capabilities, process simulation and control together with simulation techniques which allowed the system developers to set up and fine tune the whole automation package. In the framework of the implementation of the automation package, and especially of level 2, particular attention has been put upon cold rolling process modelization. To this aspect the second part of this paper has been dedicated.
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Sellés, M. A., S. R. Schmid, S. Sánchez-Caballero, V. J. Seguí, M. J. Reig, and R. Pla. "Modelization of three-layered polymer coated steel-strip ironing process using a neural network." In THE 4TH MANUFACTURING ENGINEERING SOCIETY INTERNATIONAL CONFERENCE (MESIC 2011). AIP, 2012. http://dx.doi.org/10.1063/1.4707630.

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Kupecek, Philippe, M. Comte, Jacques De Lamare, and Alain D. Petit. "Ionization yield in a three-step photoionization process of an optically thick atomic column: numerical modelization and experiments in atomic thulium." In OE/LASE'93: Optics, Electro-Optics, & Laser Applications in Science& Engineering, edited by Jeffrey A. Paisner. SPIE, 1993. http://dx.doi.org/10.1117/12.145512.

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Flores, P., J. Ambro´sio, J. C. P. Claro, and H. M. Lankarani. "Dynamics of Multibody Systems With Spherical Clearance Joints." In ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-84392.

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This work deals with a methodology to assess the influence of the spherical clearance joints in spatial multibody systems. The methodology is based on the Cartesian coordinates, being the dynamics of the joint elements modeled as impacting bodies and controlled by contact forces. The impacts and contacts are described by a continuous contact force model that accounts for geometric and mechanical characteristics of the contacting surfaces. The contact force is evaluated as function of the elastic pseudo-penetration between the impacting bodies, coupled with a nonlinear viscous-elastic factor representing the energy dissipation during the impact process. A spatial four bar mechanism is used as an illustrative example and some numerical results are presented, being the efficiency of the developed methodology discussed in the process of their presentation. The results obtained show that the inclusion of clearance joints in the modelization of spatial multibody systems significantly influences the prediction of components’ position and drastically increases the peaks in acceleration and reaction moments at the joints. Moreover, the system’s response clearly tends to be nonperiodic when a clearance joint is included in the simulation.
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Domengès, B., T. Delaroque, K. Danilo, and A. Colder. "Comprehensive Nano-Structural Approach of SSRM Nanocontact on Silicon through TEM-STEM Study." In ISTFA 2011. ASM International, 2011. http://dx.doi.org/10.31399/asm.cp.istfa2011p0132.

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Abstract Scanning Spreading Resistance Microscopy electro-mechanical nanocontacts are nowadays well understood and numerous influent parameters have been identified (Bias, load, surface state of the sample, radius of curvature of the tip). Despite several simulation and modelization possibilities, calibration curves are required to ensure reliable electrical characterizations. In this paper, we bring, through nano-structural studies (Scanning Electron Microscopy, Transmission Electron Microscopy) of surface state of both SSRM tips and doped silicon surface a new understanding of tip-sample interaction during SSRM measurements. As a result of load, a nanometric residual amorphous silicon layer was observed which thickness depends on applied force and might be due to as well the plastic transformation (Si to β-tin phase) as plough-effect residues resulting from the tip indentation into the sample. It appears thus in a failure analysis process to find the best compromise between stable electrical SSRM response and sample/tip surface degradation.
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Chiesa, Paolo, Giovanni Lozza, Ennio Macchi, and Stefano Consonni. "An Assessment of the Thermodynamic Performance of Mixed Gas-Steam Cycles: Part B — Water-Injected and Hat Cycles." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-424.

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Part B of this paper focuses on intercooled recuperated cycles where water is injected to improve both efficiency and power output. This concept is investigated for two basic cycle configurations: a Recuperated Water Injected (RWI) cycle, where water is simply injected downstream the HP compressor, and a Humid Air Turbine (HAT) cycle, where air/water mixing is accomplished in a counter-current heat/mass transfer column called “saturator”. For both configurations we discuss the selection and the optimization of the main cycle parameters, and track the variations of efficiency and specific work with overall gas turbine pressure ratio and turbine inlet temperature (TIT). TIT can vary to take advantage of lower gas turbine coolant temperatures, but only within the capabilities of current technology. For HAT cycles we also address the modelization of the saturator and the sensitivity to the most crucial characteristics of novel components (temperature differences and pressure drops in heat/mass transfer equipment). The efficiency penalties associated to each process are evaluated by a second-law analysis which also includes the cycles considered in Part A. For any given TIT in the range considered (1250 to 1500°C), the more reversible air/water mixing mechanism realized in the saturator allows HAT cycles to achieve efficiencies about 2 percentage points higher than those of RWI cycles: at the TIT of 1500°C made possible by intercooling, state-of-the-art aero-engines embodying the above cycle modifications can reach net electrical efficiencies of about 57% and 55%, respectively. This compares to efficiencies slightly below 56% achievable by combined cycles based upon large-scale heavy duty machines with TIT = 1280°C.
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Chiesa, Paolo, and Giovanni Lozza. "CO2 Emission Abatement in IGCC Power Plants by Semiclosed Cycles: Part A — With Oxygen-Blown Combustion." In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-384.

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This paper analyzes the fundamentals of IGCC power plants where carbon dioxide produced by syngas combustion can be removed, liquefied and eventually disposed, to limit the environmental problems due to the “greenhouse effect”. To achieve this goal, a semiclosed-loop gas turbine cycle using an highly-enriched CO2 mixture as working fluid was adopted. As the oxidizer, syngas combustion utilizes oxygen produced by an air separation unit. Combustion gases mainly consist of CO2 and H2O: after expansion, heat recovery and water condensation, a part of the exhausts, highly concentrated in CO2, can be easily extracted, compressed and liquefied for storage or disposal. A detailed discussion about the configuration and the thermodynamic performance of these plants is the aim of the paper. Proper attention was paid to: (i) the modelization of the gasification section and of its integration with the power cycle, (ii) the optimization of the pressure ratio due the change of the cycle working fluid, (iii) the calculation of the power consumption of the “auxiliary” equipment, including the compression train of the separated CO2 and the air separation unit. The resulting overall efficiency is in the 38–39% range, with status-of-the-art gas turbine technology, but resorting to a substantially higher pressure ratio. The extent of modifications to the gas turbine engine, with respect to commercial units, was therefore discussed. Relevant modifications are needed, but not involving changes in the technology. A second plant scheme will be considered in the second part of the paper, using air for syngas combustion and a physical absorption process to separate CO2 from nitrogen-rich exhausts. A comparison between the two options will be addressed there.
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Vannini, Giuseppe. "Rotordynamic Validation of an Ultra High Speed Multistage Centrifugal Compressor Stacked Rotor." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-27339.

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The author’s company is currently developing some centrifugal compressor prototypes where the traditional rotor design based on shrunk on wheels and spacers is not suitable due to the specific service requirements (e.g. high peripheral speed or high temperature). For instance the development of a new centrifugal compressor technology aimed to reduce the number of compressor units needed to fulfill a given service is ongoing. In order to accomplish this challenging target a very high rotational speed is required together with special “high pressure ratio” centrifugal stages. The rotor mechanical configuration which has been selected here is a stacked configuration where each centrifugal wheel is integral with the relevant shaft portion. The several shaft portions are mated together through high precision toothed connections (Hirth couplings) and the assembly is secured through a pre-stretched tie-rod. This rotor stacked configuration is not typical for the most of the industrial centrifugal compressors (a solid shaft with shrink fitted impellers is the common solution, as anticipated) but it is allowed by API standards [1], and it is referenced in Turbomachinery technical literature [2]. The rotordynamics of this special prototype is very challenging since it deals with a seven piece stacked rotor running supercritical. An extensive validation program was required in addition to careful design. This is the specific subject of the present paper which will cover the main following items: validation of the “rotor alone” rotordynamic modelization through comparison with the relevant ping test results, selection of special high speed journal bearings, and overview of the low and high speed balancing process. All these steps together finally allowed the author’s company to fully demonstrate the soundness of this stacked rotor technology for application in High Pressure Ratio Compression service.
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Martinez-Anton, Juan Carlos. "Reformulation of Optical Characterization of a Generic Thin Film-Substrate System through the Concept of Envelope-Extrema." In Optical Interference Coatings. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/oic.1998.tub.4.

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Abstract:
Optical characterization of a deposited material can be done by many experimental and analytical means as is already known [1-2], depending on some factors, like the wavelength range of interest, the thickness, the proper material parameters (n and k), the structure modelization (inhomogeneity, surface rouhgness,..), etc. The presented contribution on optical characterization is related with a new treatment of the common basic formulation. This permits simpler analytical conclusions and explicit formulas for the obtention of optical and dimensional parameters. We will proceed under the context of photometric magnitudes and optical interference coatings, so we can add interferometric information to the analysis.

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