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Auswahl der wissenschaftlichen Literatur zum Thema „Extensibilité des cycles“
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Zeitschriftenartikel zum Thema "Extensibilité des cycles"
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Choudhary, M. I., A. M. AI-Omran und A. A. Shalaby. „Physical Properties of Sandy Soil Affected by Soil Conditioner Under Wetting and Drying cycles“. Journal of Agricultural and Marine Sciences [JAMS] 3, Nr. 2 (01.06.1998): 69. http://dx.doi.org/10.24200/jams.vol3iss2pp69-74.
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Information on the effectiveness of soil conditioners over a prolonged period is scarce. A laboratory experiment was undertaken to evaluate the effectiveness of a polyacrylamide (Broadleaf P4) soil conditioner on the physical properties of sandy soil subjected to wetting and drying cycles. Four concentrations of Broadleaf P4 0, 0.2, 0.4, and 0.6% on dry weight basis were uniformly mixed with a calcareous sandy soil. Addition of Broadleaf P4 to sandy soil increased the water holding capacity, decreased the bulk density, and increased the porosity and void ratio at 0 and 16 wetting and drying cycles. The coefficient of linear extensibility increased considerably with increasing concentrations of the polymer. The addition of polymer at 0 and 16 cycles increased considerably the retention and availability of water in sandy soil. Saturated hydraulic conductivity decreased with increasing concentrations of Broadleaf P4 whereas unsaturated hydraulic conductivity at 0 and 16 cycles showed an increase with increasing soil moisture contents. After I6 wetting and drying cycles, the capacity of the soil to hold water was lost on average by 15.8% when compared to the 0 wetting and drying cycle. The effectiveness of the soil conditioner on bulk density, coefficient of linear extensibility, available water and saturated hydraulic conductivity was reduced on average by 14.1, 24.5, 21.l and 53.7% respectively. The significant changes in soil properties between 0 and 16 cycles suggested that the effectiveness of the conditioner decreased with the application of wetting and drying cycles. However, its effect was still considerable when compared to untreated soil under laboratory conditions.
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Sorensen, Lis, und Frederick Roger Harker. „Rheological Basis of Splitting in Carrot Storage Roots“. Journal of the American Society for Horticultural Science 125, Nr. 2 (März 2000): 212–16. http://dx.doi.org/10.21273/jashs.125.2.212.
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Tissue properties may strongly influence the occurrence of harvest splitting in carrot (Daucus carota L.) storage roots, a disorder generally assumed to be triggered by a high water status in the storage root. Strain within the root, as well as extensibility of root tissue by using a materials testing instrument was measured. Strain was estimated after incubation of transverse root slices in water. Measurements of the gap that developed as a result of a radial cut into the center of the slice were then used to estimate strain within the root. Extensibility of strips of carrot tissue was measured through two cycles of extension and relaxation, which allowed both elastic and plastic extensibility to be determined. Strain assessment demonstrated that carrot cells have considerable potential to increase in volume when placed in water. In some roots, phloem parenchyma adjacent to the cambium expanded to a greater extent than tissues at the periphery of the root, indicating that rigidity of cells varied across the carrot radius. Tissue extensibility was predominantly elastic, indicating the cells are unlikely to dissipate some of the strain that occurs during periods of rapid water uptake through plastic deformation. However, these measurements of extensibility were related to the properties of cells along the entire 20-mm length of the tissue strip that was used. Because we demonstrated that mechanical properties can vary within a small distance, it is concluded that future studies into the mechanical properties of carrot storage root tissue will rely on empirical strain measurements.
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Bell, David R., Megan P. Myrick, J. Troy Blackburn, Sandra J. Shultz, Kevin M. Guskiewicz und Darin A. Padua. „The Effect of Menstrual-Cycle Phase on Hamstring Extensibility and Muscle Stiffness“. Journal of Sport Rehabilitation 18, Nr. 4 (November 2009): 553–63. http://dx.doi.org/10.1123/jsr.18.4.553.
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Context:Preventing noncontact ACL injuries has been a major focus of athletic trainers and researchers. One factor that may influence female noncontact ACL injury is the fluctuating concentrations of hormones in the body.Objective:To determine whether muscle properties change across the menstrual cycle.Design:Repeated measures. Testing was performed within 3 d after the onset of menses and ovulation. Repeated-measures ANOVAs were used to determine changes in variables across the menstrual cycle, and Pearson correlations were used to determine relationships between variables.Participants:8 women with normal menstrual cycles.Main Outcome Measures:Active hamstring stiffness and hamstring extensibility.Results:Hamstring extensibility (P = .003) increased at the ovulation testing session but hamstring muscle stiffness (P = .66) did not.Conclusions:The results indicate that hamstring muscle stiffness did not change across the menstrual cycle and hamstring extensibility increased at ovulation, when estrogen concentration increases.
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Ma, Xing Bin, Xiao Yan Liu, Lai Liang Zhang und Qiang Lv. „Cycle Properties of s-Vertex Connected Graphs“. Advanced Materials Research 756-759 (September 2013): 4703–5. http://dx.doi.org/10.4028/www.scientific.net/amr.756-759.4703.
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The cycle properties of-vertex connected graph are studied as follows pancyclicity and fully cycle extensibility. Two conclusions are drawn by way of argument: Let be a-vertex connected graph, if ,then is fully cycle extendable. Here the upper bound of is best possible. Let be a-vertex connected graph, if ,then is a pancyclic graph or .
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Wadsworth, Larry C., Hannah Suh und Charles Allen. „Cotton-Surfaced Nonwovens for Short-Wear-Cycle Apparel“. International Nonwovens Journal os-9, Nr. 2 (Juni 2000): 1558925000OS—90. http://dx.doi.org/10.1177/1558925000os-900214.
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Cotton-surfaced nonwovens have been developed with cotton on one side or both sides of a core structure in which the cotton content varies from 41–75% of the fabric weight. The thermally bonded two or three layered laminates are soft but strong and have a hand similar to cotton knits or hydroentangled fabrics. The fabrics have also demonstrated excellent wetting, wicking rates, water adsorption and water retention properties. Although these novel fabrics have notable flexibility and extensibility as produced, a post-treatment process provides the fabrics with instantaneous elastic recoveries ranging from 83–93% from an extension of 50%. The fabrics exhibit minimal linting characteristics and would be suitable as medical isolation gowns, head covers and shoe covers, bed sheets, pillow cases and for consumer applications such as disposable underwear, towels, wipers and personal hygiene products.
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Salih, Salih M., und Abdalwhhab I. Al abaied. „Effect of Super Absorbent Polymer and Ceratophyllum Powder Application on Some Soil Physical Properties“. IOP Conference Series: Earth and Environmental Science 1222, Nr. 1 (01.08.2023): 012030. http://dx.doi.org/10.1088/1755-1315/1222/1/012030.
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Abstract A two factorial laboratory experiment was conducted according to randomized complete block design with three replications, to investigate the effect of super absorbent polymer (SAP) and ceratophyllum powder application on some physical characteristics of loamy sand soil. The first factor included three levels of super absorbent polymer, namely 0,0.2, and 0.4 %. While the second factor consists of three levels of ceratophyllum powder i.e., 0,2, and 4 %. The treated soil (treated with super absorbent polymer and ceratophyllum powder) was exposed to 14 cycles of wetting and drying. Effect of experiments factors on coefficient of linear extensibility, soil bulk density and total porosity were measured. The obtained results show that the super absorbent polymer and ceratophyllum powder application led to increase the dry soil bulk density, total porosity, and the coefficient of linear extensibility values for all application levels. Regarding the soil aggregate stability, a significant increase was observed under effect of super absorbent polymer and ceratophyllum powder application. Where the highest value of soil aggregate stability was recorded at 0.4% level of SAP reached 54.2%. Likewise, the highest value of soil aggregate stability under effect of ceratophyllum powder application reached 30.7% at 4% level of application, compare to the control treatment that gave 11.1 % with increasing rate reached 76.5%. In same direction, all moisture content had increased under effect of study factors. However, the super absorbent polymer was superior to ceratophyllum powder application.
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Clément, F., L. Bokobza und L. Monnerie. „On the Mullins Effect in Silica-Filled Polydimethylsiloxane Networks“. Rubber Chemistry and Technology 74, Nr. 5 (01.11.2001): 847–70. http://dx.doi.org/10.5254/1.3547657.
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Abstract Silica-filled polydimethylsiloxane networks are submitted to successive stretching cycles, in order to get the stabilized stretching curve, at variable temperature. This study explains the peculiar temperature dependence of the first stretching curve of filled rubbers, and highlights the molecular origin of the stress-softening phenomenon, known as Mullins effect. Thanks to the comparison between the strain dependence of stress and the molecular orientation, this effect is attributed to the detachment from the filler surface or slippage on the filler surface, of chains having reached their limit of extensibility. Moreover, by taking advantage of Atomic Force Microscopy observations on stretched samples, the Mullins effect is shown to take place mainly in regions of high local concentration of silica. The experimental results are also compared to Bueche's model for the Mullins effect.
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Sun, Xiao Yu, und Zhen Qing Wang. „The Non-Linear Analysis of Cable“. Advanced Materials Research 430-432 (Januar 2012): 1632–35. http://dx.doi.org/10.4028/www.scientific.net/amr.430-432.1632.
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The paper reports an investigation on a continuous model for dynamics of cables, taking bending stiffness and sag extensibility into account. The new approach involves the use of derived sensitivity coefficients associated with various cable parameters of interest, and use these coefficients to achieve optimal cable performance. The fatigue damage is calculated in the time domain through an adequate cycles counting method. A discussion of the influence of the Irvine parameter on the total fatigue damage is then performed. A Monte Carlo parametric analysis on a case-study,representative of a suspended cable typical of overhead power-line applications, especially in cyclic exposure, exceeds the present chromate-based systems.introduces a discussion on the convergence of the modal expansions and highlights the respective importance of the different classes of non-linear terms included in the model.
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Cookson, P. G., und A. G. De Boos. „Effects of Synthappret BAP-Based Treatments on the Cuff-Edge Felting and Mechanical Properties of a Lightweight Woven Wool Fabric“. Textile Research Journal 62, Nr. 10 (Oktober 1992): 595–602. http://dx.doi.org/10.1177/004051759206201007.
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Cuff-edge felting of a pure wool shirting fabric treated with Synthappret BAP, either alone or in combination with a polyurethane or polyacrylate, has been examined. Using appropriate levels of polymer, cuff-edge felting was prevented after the recommended test of five 5A washing cycles in a Wascator. The inherent stiffness of the polymer-treated fabric was reduced by washing, decatizing or, especially, dry-cleaning; reductions in bending rigidity were accompanied by increases in extensibility. Scanning electron micrograph studies showed that mechanical action along a cuff edge during washing caused fiber damage and failure of the polymer. Mechanical action also occurred during dry-cleaning, and this lead to more severe cuff-edge felting as a result of subsequent washing. The level of weave crimp has a major bearing on cuff-edge felting.
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Zhang, Kaicheng, Guobing Ying, Lu Liu, Fengchen Ma, Lin Su, Chen Zhang, Donghai Wu, Xiang Wang und Ying Zhou. „Three-Dimensional Porous Ti3C2Tx-NiO Composite Electrodes with Enhanced Electrochemical Performance for Supercapacitors“. Materials 12, Nr. 1 (08.01.2019): 188. http://dx.doi.org/10.3390/ma12010188.
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Ti3C2Tx and Ti3C2Tx-NiO composites with three-dimensional (3D) porous networks were successfully fabricated via vacuum freeze-drying. The microstructure, absorption, and electrochemical properties of the developed composites were investigated. Nickel oxide (NiO) nanoparticles could be evenly distributed on the three-dimensional network of three-dimensional Ti3C2Tx using solution processing. When employed as electrochemical capacitor electrodes in 1 M environmentally friendly sodium sulfate, Na2SO4, solution, the three-dimensional porous Ti3C2Tx-NiO composite electrodes exhibited considerable volume specific capacitance as compared to three-dimensional porous Ti3C2Tx. The three-dimensional porous Ti3C2Tx-NiO composite delivered a remarkable cycling performance with a capacitance retention of up to 114% over 2500 cycles. The growth trend of the capacitance with NiO content shows that nickel oxide plays a crucial role in the composite electrodes. These results present a roadmap for the development of convenient and economical supercapacitors in consideration with the possibilities of morphological control and the extensibility of the process.
Dissertationen zum Thema "Extensibilité des cycles"
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Ouyang, Qiancheng. „Some colouring problems in edge/vertex-coloured graphs : Structural and extremal studies“. Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASG060.
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La coloration de graphes est l'un des sujets les plus connus, populaires et largement étudiés dans le domaine de la théorie des graphes, avec une vaste littérature comprenant des approches provenant de nombreux domaines ainsi que de nombreux problèmes qui sont encore ouverts et étudiés par divers mathématiciens et informaticiens à travers le monde. Le Problème des Quatre Couleurs, à l'origine de l'étude de la coloration des graphes, a été l'un des problèmes centraux en théorie des graphes au siècle dernier. Il demande s'il est possible de colorer proprement chaque graphe planaire avec quatre couleurs. Malgré son origine théorique, la coloration des graphes a trouvé de nombreuses applications pratiques telles que la planification, les problèmes d'assignation de fréquences, la segmentation, etc. Le Problème des Quatre Couleurs est l'un des problèmes importants parmi de nombreux problèmes de la théorie des graphes chromatiques, à partir duquel de nombreuses variantes et généralisations ont été proposées. Tout d'abord, dans cette thèse, nous visons à optimiser la stratégie de coloration des sommets de graphes et d'hypergraphes avec certaines contraintes données, en combinant le concept de coloration propre et d'élément représentatif de certains sous-ensembles de sommets. D'autre part, en fonction du sujet à colorer, une grande quantité de recherches et de problèmes de graphes à arêtes colorées ont émergé, avec des applications importantes en biologie et en technologies web. Nous fournissons quelques résultats analogues pour certaines questions de connectivité, afin de décrire des graphes dont les arêtes sont attribuées suffisamment de couleurs, garantissant ainsi des arbres couvrants ou des cycles ayant une structure chromatique spécifiqueGraph colouring is one of the best known, popular and extensively researched subject in the field of graph theory, having a wide literature with approaches from many domains and a lot of problems, which are still open and studied by various mathematicians and computer scientists along the world. The Four Colour Problem, originating the study of graph colouring, was one of the central problem in graph theory in the last century, which asks if it is possible to colour every planar graph properly by four colours. Despite the theoretical origin, the graph colouring has found many applications in practice like scheduling, frequency assignment problems, segmentation, etc. The Four Colour Problem is a significant one among many problems in chromatic graph theory, from which many variants and generalizations have been proposed. Firstly, in this thesis, we aim to optimize the strategy to colour the vertex of graphs and hypergraphs with some given constraints, which combines the concept of proper colouring and representative element of some vertex subsets. On the other hand, according to the subject to be coloured, a large amount of research and problems of edge-coloured graphs have emerged, which have important applications to biology and web technologies. We provide some analogous results for some connectivity issues—to describe graphs whose edges are assigned enough colours, that guarantee spanning trees or cycles of a specific chromatic structure
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Pate, Megan Padua Darin A. „Assessment of muscle stiffness, electromechanical delay, and muscle extensibility over the course of the menstrual cycle“. Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1069.
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Thesis (M.A.)--University of North Carolina at Chapel Hill, 2007.Title from electronic title page (viewed Mar. 27, 2008). "... in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Exercise and Sport Science Athletic Training." Discipline: Exercise and Sports Science; Department/School: Exercise and Sport Science.
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Crouch, Viv, und Anna Goldstein. „A HIGH-DEMAND TELEMETRY SYSTEM THAT MAXIMISES FUTURE EXPANSION AT MINIMUM LIFE-CYCLE COST“. International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/608556.
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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, CaliforniaThe Aircraft Research and Development Unit (ARDU) of the Royal Australian Air Force (RAAF) is the only agency in Australia that performs the full spectrum of military flight testing and is the new custodian of the instrumented weapons range at Woomera. Receiving early attention will be the upgrade and integration of ARDU's telemetry systems with the meteorological and tracking data acquisition capabilities at Woomera to minimize overhead and data turnaround time. To achieve these goals, maximum modularity, extensibility, and product interoperability is being sought in the proposed architecture of all the systems that will need to cooperate on the forecast test programmes. These goals are also driven by the need to be responsive to a wide variety of tasks which presently include structural flight testing of fighter and training aircraft, weapons systems performance evaluation on a variety of combatant aircraft, and a host of other tasks associated with all fixed and rotary wing aircraft in the Army and Air Force inventory. Of all these tasks however, ARDU sees that responsiveness to future testing of F-111Cs fitted with unique Digital Flight Control Systems along with USAF standard F-111Gs may place the most significant demands on data handling —particularly in regard to providing an avionics bus diagnostic capability when performing Operational Flight Programme (OFP) changes to the mission computers. With the timely assistance and advice of Loral Test & Information Systems, who has long-term experience in supporting USAF F-111 test programmes, ARDU is confident of making wise design decisions that will provide the desired flexibility and, at the same time, minimize life-cycle costs by ensuring compliance with the appropriate telemetry and open systems standards. As well, via cooperative agreements with the USAF, the potential exists to acquire proven software products without needing to fund the development costs already absorbed by the USAF. This paper presents ARDU's perception of future needs, a view by LTIS of how best to meet those needs, and, based on ARDU data, a view of how LTIS' proposal will satisfy the requirement to provide maximum extensibility with minimum life-cycle costs.
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Dombroski, Erik. „The influence of cyclic loading on the extensibility of human hamstring muscle-tendon units in vivo a thesis submitted in partial fulfilment for the degree of Master of Health Science, Auckland University of Technology, 2005“. Full thesis. Abstract, 2005. http://puka2.aut.ac.nz/ait/theses/DombroskiE.pdf.
Der volle Inhalt der QuelleKonferenzberichte zum Thema "Extensibilité des cycles"
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Wagenseil, Jessica E., Chris H. Ciliberto, Russel H. Knutsen, Marilyn A. Levy, Attila Kovacs und Robert P. Mecham. „Developmental Cardiovascular Remodeling Associated With Reduced Elastin Levels in Mice Occurs After Embryonic Day 18“. In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-204476.
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Elastin provides reversible extensibility and stores energy during the cardiac cycle in large blood vessels. It is only present in vertebrate animals with a closed circulatory system and high, pulsatile blood pressures. Elastin is crucial for proper cardiac function in vertebrates, as mice lacking elastin (eln-/-) die soon after birth with cardiovascular abnormalities including long, tortuous, stenotic, stiff arteries and high left ventricular (LV) pressure with low cardiac output [1, 2].
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Bondarev, B., A. Bondarev, A. Korneeva und E. Basinskikh. „WOOD-GLASS-FIBER COMPOSITE MATERIALS BASED ON POLYESTER RESINS FOR TIMBER RAILWAY SLEEPER STRUCTURES“. In Modern machines, equipment and IT solutions for industrial complex: theory and practice. FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov, 2021. http://dx.doi.org/10.34220/mmeitsic2021_198-204.
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Wood-glass-fiber composite materials (WGFCM) are used in transport construction (sleepers, switch bars, etc.). Polymer solutions based on furfuralacetone monomer (FAM) served as a matrix for the manufacture of WGFCM. The article suggests using Holex HAS- 2061 polyester resin as a matrix, which, in turn, has chemical resistance, dielectric properties, increased impact strength, having sufficient strength characteristics, and significant extensibility. For the application of the above material in the structural elements of sleepers of logging railways, it is necessary to know its operation under repeated loading. Endurance experiments were conducted at different coefficients of the load application cycle asymmetry pb=0,1; 0,3; 0,6. As a result of the experiments, the values of the endurance limit of the material under study were obtained, which allow us to conclude that it can be used in the construction of timber railway sleepers.
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Morovati, Vahid, und Roozbeh Dargazany. „Micro-Mechanical Modeling of the Stress Softening in Double-Network Hydrogels“. In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-88252.
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While single network hydrogels show limited extensibility and low strength, double-network hydrogels benefit from significantly high stretchability and toughness due to their reinforcing mechanism of combining two soft and rigid networks. Here, a micro-mechanical model is developed to characterize the constitutive behavior of DN hydrogels in quasi-static large deformation. In particular, we focused on describing the permanent damage in DN gels under large deformations. Irreversible chain detachment and decomposition of the first network are explored as the underlying reasons for the nonlinear inelastic phenomenon. The proposed model enables us to describe the damage and the way it influences the micro-structure of the gel. The model is validated with uni-axial loading and unloading experiments of DN gels. The proposed model contains a few numbers of material constants and shows a good agreement with cyclic uni-axial test data.
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Tong, Michael T., und Bret A. Naylor. „An Object-Oriented Computer Code for Aircraft Engine Weight Estimation“. In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-50062.
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Reliable engine-weight estimation at the conceptual design stage is critical to the development of new aircraft engines. It helps to identify the best engine concept amongst several candidates. At NASA Glenn (GRC), the Weight Analysis of Turbine Engines (WATE) computer code, originally developed by Boeing Aircraft, has been used to estimate the engine weight of various conceptual engine designs. The code, written in FORTRAN, was originally developed for NASA in 1979. Since then, substantial improvements have been made to the code to improve the weight calculations for most of the engine components. Most recently, to improve the maintainability and extensibility of WATE, the FORTRAN code has been converted into an object-oriented version. The conversion was done within the NASA’s NPSS (Numerical Propulsion System Simulation) framework. This enables WATE to interact seamlessly with the thermodynamic cycle model which provides component flow data such as airflows, temperatures, and pressures, etc. that are required for sizing the components and weight calculations. The tighter integration between the NPSS and WATE would greatly enhance system-level analysis and optimization capabilities. It also would facilitate the enhancement of the WATE code for next-generation aircraft and space propulsion systems. In this paper, the architecture of the object-oriented WATE code (or WATE++) is described. Both the FORTRAN and object-oriented versions of the code are employed to compute the dimensions and weight of a 300-passenger aircraft engine (GE90 class). Both versions of the code produce essentially identical results as should be the case.
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Mohammadi, Hossein, Raymond Cartier und Rosaire Mongrain. „Development of a 1D Model for Assessing the Aortic Root Pressure Drop With Viscosity and Compliance“. In ASME 2013 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/sbc2013-14749.
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Aging and some pathologies such as arterial hypertension, diabetes, hyperglycemia, and hyperinsulimenia cause some geometrical and mechanical changes in the aortic valve microstructure. Cupsal thickening and lost of extensibility (increasing stiffness) are the consequences of these changes in the aortic valve which have a negative impact on the function of the valve [1]. The most frequent form of diseases of the aortic valve is the calcific aortic stenosis which is responsible for 80% of the North American deaths due to valvular heart diseases [2]. In this pathology, calcified nodules on the valve leaflets occur which lead to the thickening and stiffening of the leaflets and restricting the natural motion of the valve which presents an increased resistance to forward blood flow during the ejection phase of the cardiac cycle. To reduce the mortality and morbidity from the aortic stenosis, clinical management and proper diagnosis are essential [3]. Tranvalvular pressure gradient (TPG) and the effective orifice area (EOA), the minimum cross sectional area of the blood flow across the stenosis, are the most commonly used indices for assessing the aortic stenosis [4]. Numerous studies have been done to relate the TPG across the stenosis to the blood flow rate and EOA. Gorlin (1951) was the first to establish a relationship between TPG and EOA [5]. Several studies have reported deviations in valve area calculation by using Gorlin formula. This formula was derived based on some assumptions such as rigid circular orifice, non viscous and steady flow, while valvular orifices are compliant and the flow through them is viscous and pulsatile [6]. Several corrections have been proposed. However, even with these improved formula, significant deviations are still reported [7]. Calark (1978), Bermejo et al (2002) and Garcia et al (2006), by presenting a theoretical model, tried to express TPG in terms of the blood flow rate and EOA [8–10]. None of these studies considered the effect of the aortic root compliance on TPG. Nobari et al reported that the stiffening of the aorta changes the pressure drop and affects the leaflets motion [11]. Therefore, the objective of this study is to develop a 1D model for assessing the aortic pressure drop for the transient viscous blood flow across the aortic stenosis, by taking into account the vessel wall compliance. The derived TPG will be expressed in terms of the surrogate variables which are anatomical and hemodynamic data meaningful and accessible for physicians.
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Biniwale, Shripad, Samad Ali, Osama Hasan Khan, Wentao Zhou, Ksenia Efimova und Masahiro Takahashi. „An Innovative and Practical Integrated Asset Model: Optimisation from Pore to Process with Automatic Model Update“. In International Petroleum Technology Conference. IPTC, 2021. http://dx.doi.org/10.2523/iptc-21295-ms.
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Abstract One of the major challenges the oil and gas industry faces is the enablement of fast and seamless multi-disciplinary integration across the reservoir, production, network and facilities. Integrated Asset Management (IAM) is a key concept for making critical decisions about assets development and to maximise asset value. Although the IAM concept has been used in the past, it's tough to implement due to its inherent complexities. This paper introduces the latest technical innovations and processes that make IAM approach practical and reliable for its implementation. This innovative solution offers flexibility to rapidly adjust the model through "automatic and fast model updates" and provides a fit-for-purpose integrated model. The solution improves the speed and accuracy of decisions, and assists in field development planning workflows, modelling operational challenges and addressing debottlenecking options while considering all the domain constraints and development scenarios. Integrated asset modelling methodology used in this paper, is flexible in capturing domain science at different fidelity levels, incorporating fit for purpose physics, ranging from analytical models to highly complex reservoir simulation models with high-resolution grids that capture geological complexity. Operational logic design and decision cycle implementation for production forecasting are leveraged from an implicitly coupled scheduler, referred to as "Field management". Surface network integration in the integrated asset model is flexible and dependent on the level of fidelity needed – with complete control of all entities inside the surface network model provided by the "Field management" system. Optimisation capabilities provided with the "Field management" system allows for "automatic updates" to entities in the production system to optimise the recovery. "Model updates" pertinent to production data updates is driven by the "rapid model update" technique. Flexible coupling techniques and niche optimisation capabilities offered by the "Field management" scheduler between the different domain models enable optimising the asset's production with implicit operational constraints. The superior performance offered through state-of-the-art solvers, fit for purpose fidelity and parallel scalability offers a practical advantage to this integrated asset management approach. "Rapid model update" workflow allows for seamless and fast integration of production data updates within the integrated asset model, thereby keeping the model in an "evergreen" state, reflective of the subsurface dynamics and operational changes. This paper provides the most practical solution for Integrated asset modelling implementation that provides flexibility to balance between performance and fidelity by leveraging the latest technological advancements and workflows. It is the first solution that offers an optimisation technique capable of "rapid and automatic model updates" and python extensibility to achieve realistic field planning forecasts.
Berichte der Organisationen zum Thema "Extensibilité des cycles"
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Parker, S. A., und R. H. Mumm. Extensibility Experiments with the Software Life-Cycle Support Environment. Fort Belvoir, VA: Defense Technical Information Center, November 1991. http://dx.doi.org/10.21236/ada247696.
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