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Search results for: COUPLING DYNAMIC EQUATIONS
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Advanced Experimental and Numerical Analysis of Behavior Structural Materials Including Dynamic Conditions of Fracture for Needs of Designing Protective Structures
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Structural Analysis and Dynamic Processes of the Transmembrane Segment Inside Different Micellar Environments—Implications for the TM4 Fragment of the Bilitranslocase Protein
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Dynamic mechanical properties and thermal degradation process of the compositions obtainedfrom unsaturated poly(ester urethanes) cross-linked with styrene
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Picomolar analysis of flavins in biological samples by dynamic pH junction-sweeping capillary electrophoresis with laser-induced fluorescence detection
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Influence of e-beam irradiation on the dynamic creep and fatigue properties of poly(aliphatic/aromatic-ester) copolymers for biomedical applications
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The impact of air humidity on the operation of proton exchange membrane fuel cells determined using dynamic electrochemical impedance spectroscopy
PublicationThis paper describes the changes in the fuel cell impedance across a range of current loads and humidity changes. The changes of each equivalent circuit parameters representing specific processes occurring in fuel cells, as a function of humidity and current changes, were determined. Within the combined scope of current and humidity, the optimal working conditions of the cells were determined, corresponding to the lowest impedance...
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Computational simulations of concrete behaviour under dynamic conditions using elasto-visco-plastic model with non-local softening
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Computational simulations of concrete behaviour under dynamic conditions using elasto-visco-plastic model with non-local softening.
PublicationW artykule przedstawiono wyniki obliczeniowych symulacji zachowania betonu w warunkach dynamicznych stosując sprężysto-lepko-plastyczny model z nielokalnym osłabieniem. Wykonano obliczenia dla ściskania jednoosiowego, rozciągania jednoosiowego i zginania. Dla dużych prędkości obciążenia uwzględniono fragmentację materiału. Wyniki porównano z doswiadczeniami.
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Straightened characteristics of McKendrick-von Foerster equation
PublicationWe study the McKendrick-von Foerster equation with renewal (that is the age-structured model, with total population dependent coefficient and nonlinearity). By using a change of variables, the model is then transformed to a standard age-structured model in which the total population dependent coefficient of the transport term reduces to a constant 1. We use this transformation to get existence, uniqueness of solutions of the problem...
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Thermo-resonance analysis of an excited graphene sheet using a new approach
PublicationForced vibration of graphene nanoplate based on a refined plate theory in conjunction with higher-order nonlocal strain gradient theory in the thermal environment has been investigated. Regarding the higher-order nonlocal strain gradient theory, both stress nonlocality and size-dependent effects are taken into account, so the equilibrium equations which are governing on the graphene sheet have been formulated by the theory....
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Dynamic electrochemical impedance spectroscopy and polarization studies to evaluate the inhibition effect of benzotriazole on copper-manganese-aluminium alloy in artificial seawater
PublicationPrzeprowadzono badania wpływu benzotriazolu (BTA) na korozję nowego typ mosiądzu (CMA) w środowisku syntetycznej wody morskiej przy użyciu dynamicznej elektrochemicznej spektroskopii impedancyjnej (DEIS), techniki polaryzacji rezystancyjnej i ekstrapolacji krzywych Tafela. Wyniki pomiarowe otrzymane przy użyciu tych metod wskazują spadek szybkości korozji wraz ze wzrostem stężenia BTA. Wskazuje to na inhibicyjne własności BTA w...
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A Dynamic Forecast Demand Scenario Analysis to Design an Automated Parcel Lockers Network in Pamplona (Spain) Using a Simulation-Optimization Model
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Dynamic mechanical properties and thermal degradation process of the compositions obtained from unsaturated poly(ester urethanes) cross-linked with styrene
PublicationW pracy przedstawiono właściwości dynamiczno-mechaniczne oraz stabilność termiczną poli(estro uretanów) sieciowanych styrenem. Badane poli(estro uretany) syntetyzowano z nienasyconych oligomeroli opartych na cis-2-buten-1,4-diolu oraz 4,4`-diizocyjanianie difenylometanu. Wyniki badań dynamicznych właściwości mechanicznych otrzymanych poliuretanów potwierdziły separację fazową uzyskanych kompozycji. W pracy przedstawiono również...
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Thermal decomposition of some aromatic azomonoethers. Part II. Non-isothermal study of three liquid crystals in dynamic air atmosphere
PublicationW ramach pracy zweryfikowano stabilność termiczną trzech barwników azowych o właściwościach ciekłokrystalicznych - potencjalnych prekursorów do otrzymywania warstw stosowanych w optyce nieliniowej. Zarejestrowano przebiegi TG, DTG, DTA oraz DSC jak również analizowano skład gazów powstających podczas rozpadu za pomocą przystawki FTIR. Przeprowadzono analizę kinetyki rozkładu, wyznaczając energię aktywacji procesu.
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Effect of Pin Shape on Thermal History of Aluminum-Steel Friction Stir Welded Joint: Computational Fluid Dynamic Modeling and Validation
PublicationThis article studied the effects of pin angle on heat generation and temperature distribution during friction stir welding (FSW) of AA1100 aluminum alloy and St-14 low carbon steel. A validated computational fluid dynamics (CFD) model was implemented to simulate the FSW process. Scanning electron microscopy (SEM) was employed in order to investigate internal materials’ flow. Simulation results revealed that the mechanical work...
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Two-dimensional vertical Reynolds-averaged naviers-stokes equations versus one-dimensional Saint-Venant model for rapidly varied open channel water flow modelling
PublicationPrzedstawiono dwa modele przepływu wody ze swobodną powierzchnią -płaski pionowy model Reynoldsa i model de Saint-Venanta.Do rozwiązania równań pierwszego modelu zastosowano schemat SIMPLE oraz wykorzystano metodę cząstek znaczonych MAC do wyznaczania swobodnej powierzchni wody. Równania Saint-Venanta rozwiązano metodą objętości skończonych. Obydwa modele zastosowano do symulacj zjawiska typu katastrofa zapory. Porównano wyniki...
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On the Fenchel–Moreau conjugate of G-function and the second derivative of the modular in anisotropic Orlicz spaces
PublicationIn this paper, we investigate the properties of the Fenchel–Moreau conjugate of G-function with respect to the coupling function c(x, A) = |A[x]2 |. We provide conditions that guarantee that the conjugate is also a G-function. We also show that if a G-function G is twice differentiable and its second derivative belongs to the Orlicz space generated by the Fenchel–Moreau conjugate of G then the modular generated by G is twice differentiable...
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A DISCRETE-CONTINUOUS METHOD OF MECHANICAL SYSTEM MODELLING
PublicationThe paper describes a discrete-continuous method of dynamic system modelling. The presented approach is hybrid in its nature, as it combines the advantages of spatial discretization methods with those of continuous system modelling methods. In the proposed method, a three-dimensional system is discretised in two directions only, with the third direction remaining continuous. The thus obtained discrete-continuous model is described...
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Performance evaluation of an improved optical computed tomography polymer gel dosimeter system for 3D dose verification of static and dynamic phantom deliveries
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Multicast Traffic Throughput Maximization through Joint Dynamic Modulation and Coding Schemes Assignment, and Transmission Power Control in Wireless Sensor Networks
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Fixed final time and free final state optimal control problem for fractional dynamic systems – linear quadratic discrete-time case
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Increased inspiratory resistance alters the cardiac contribution to the dynamic relationship between blood pressure and pial artery pulsation oscillations in healthy subjects
PublicationThere is increasing evidence that heart performance directly influences cerebral perfusion. We hypothesised that increased inspiratory resistance will affect the cardiac contribution to the relationship between blood pressure and pial artery pulsation oscillations.
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Influence of gas turbine controller adjustment on propulsion system behaviour in high sea conditions. Part 1. The dynamic model of propulsion system.
PublicationDo badań przyjęto układ napędowy okrętowy z turbinami gazowymi napędzającymi poprzez przekładnię mechaniczną zębatą śrubę okrętową o zmiennym skoku. Nakład napędowy statku z turbinami gazowymi napędzającymi śrubę nastawną oddziałują wymuszenia zarówno od nastaw prędkości obrotowej wału śrubowego jaki skoku śruby napędowej, ale również istnieje silna reakcja od falowania morza (stanu morza) na pracę układu napędowego. Zbudowano...
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Electromagnetic forced vibrations of composite nanoplates using nonlocal strain gradient theory
PublicationThis article is intended to analyze forced vibrations of a piezoelectric-piezomagnetic ceramic nanoplate by a new refined shear deformation plate theory in conjunction with higher-order nonlocal strain gradient theory. As both stress nonlocality and strain gradient size-dependent effects are taken into account using the higher-order nonlocal strain gradient theory, the governing equations of the composite nanoplate are formulated....
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On forced vibrations of piezo-flexomagnetic nano-actuator beams
PublicationThe effect of excitation frequency on the piezomagnetic Euler-Bernoulli nanobeam taking the flexomagnetic material phenomenon into consideration is investigated in this chapter. The magnetization with strain gradients creates flexomagneticity. We couple simultaneously the piezomagnetic and flexomagnetic properties in an inverse magnetization. Resemble the flexoelectricity, the flexomagneticity is also size-dependent. So, it has...
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Damped forced vibration analysis of single-walled carbon nanotubes resting on viscoelastic foundation in thermal environment using nonlocal strain gradient theory
PublicationIn this paper, the damped forced vibration of single-walled carbon nanotubes (SWCNTs) is analyzed using a new shear deformation beam theory. The SWCNTs are modeled as a flexible beam on the viscoelastic foundation embedded in the thermal environment and subjected to a transverse dynamic load. The equilibrium equations are formulated by the new shear deformation beam theory which is accompanied with higher-order nonlocal strain...
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Discussion on “Dynamic soil-structure interaction: A three-dimensional numerical approach and its application to the Lotung case study”. Poor performance of the HSS model
PublicationThe Hardening Soil Small (HSS) is a constitutive model being extension to the well established Hardening Soil Model (HS) accounting for the nonlinearity of small strain stiffness. It is implemented in commercial finite element computer codes for geotechnical analyses and used widely in research and design. The article deals with a problem known as overshooting after very small load reversals. It induces much higher stiffness than...
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Influence of adjustment of gas turbine controller on ship propulsion system behaviour in rough sea conditions. Part 1. The dynamic model of propulsion system.
PublicationPrzedstawiono model dynamiki układu napędowego okrętowego, wykorzystując metodę elementów skończonych. Układ napędowy składa się z dwóch turbin gazowych napędzających poprzez przekładnię mechaniczną zębatą pędnik o nastawnym skoku. W symulacji układu napędowego można zadawać wymuszenia wartością zadaną nastaw prędkości na regulatorze, wymuszenia od falowania morza w zależności od stanu morza, jak również zmianą ustawienia skoku...
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Analog modelling in qualitative analysis of vibration propagation
PublicationThe theory of dynamic systems is usually used to model the real systems. The models are based on solving ordinary differential equations, partial or difference, which enable obtaining the relation between input signal and the system response (output signal). The analogy between those models and generalized dynamic systems or control systems can be practically used. Vibration propagation can be described in a similar way as the...
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X-Ray Diffraction, Mössbauer Spectroscopy and Magnetoelectric Effect Studies of Multiferroic Bi5Ti3FeO15 Ceramics
PublicationBi5Ti3FeO15 ceramics belongs to multiferroic class of materials. In this work it was prepared by solid-state sintering method and investigated by X-ray diffraction, Mössbauer spectroscopy, and magnetoelectric effect measurements. As it was proved by X-ray diffraction studies the single-phase Bi5Ti3FeO15 compound was obtained. The Mössbauer investigations revealed paramagnetic character of the compound at room temperature as well...
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Equations of tribological parameters for liquid flow in boundary layer on the tissue surface in bioreactor = Wyznaczanie parametrów tribologicznych dla przepływu cieczy w warstwie granicznej na powierzchni tkanki w bioreaktorze
PublicationW niniejszej pracy przedstawiony został problem tribologiczny wynikający z przepływu nieustalonego odżywczej cieczy lepkiej w cienkiej warstwie przyściennej w bezpośrednim kontakcie z zewnętrzną powierzchnią warstwy wierzchniej wzrastających komórek (chondrocytów) w trakcie procesu ich hodowli w bioreaktorze. Efektem rozważań będą wartości sił tarcia powstające na powierzchni wzrastającej tkanki. Najnowsze badania wykazały lepszą...
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One-Dimensional Modeling of Flows in Open Channels
PublicationIn this chapter, modeling of the unsteady open channel flow using one-dimensional approach is considered. As this question belongs to the well-known and standard problems of open channel hydraulic engineering, comprehensively presented and described in many books and publications, our attention is focused on some selected aspects only. As far as the numerical solution of the governing equations is considered, one can find out that...
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Nonlinear generation of non-acoustic modes by low-frequency sound in a vibrationally relaxing gas
PublicationTwo dynamic equations referring to a weakly nonlinear and weakly dispersive flow of a gas in which molecular vibrational relaxation takes place. are derived. The first one governs an excess temperature associated with the thermal mode, and the second one describes variations in vibrational energy. Both quantities refer to non-wave types of gas motion. These variations are caused by the nonlinear transfer of acoustic energy into...
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Kinedynamics of Spherical Wavefields in Fluid and Dielectric Continua
PublicationDistubances induced by physical sources in fluids or dielectrics maintain their primary character while propagating throughout either of these bi-dynamic continua. The paper defines and illustrates four sets of bi-fields based on four specific fundamental kinedynamic solutions to inhomogeneous wave equations related to quasi-point acoustic and electromagnetic sources.
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A MULTI-MASS DISCRETE MODEL OF TRIBOMETER FOR THE RESEARCH ON DYNAMIC FRICTION CHARACTERISTICS = Wielomasowy dyskretny model tribometru do symulacyjnych badań dynamicznych charakterystyk tarcia
PublicationW artykule przedstawiono metodykę opracowaną w celu redukcji modelu fizycznego tribometru z ciągłym rozkładem masy (bezwładności), sztywności podparcia oraz tłumienia do modelu dyskretnego. W modelu dyskretnym zastosowano zastępcze masy skupione i elementy sprężysto - tłumiące, których właściwości są dobrane w taki sposób, że charakterystyka drgań własnych tego modelu odpowiada charakterystyce rzeczywistego układu fizycznego. Dzięki...
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On the non-linear dynamics of torus-shaped and cylindrical shell structures
PublicationIn this study, the non-linear dynamic analysis of torus-shaped and cylindrical shell-like structures has been studied. The applied material is assumed as the functionally graded material (FGM). The structures are considered to be used for important machines such as wind turbines. The effects of some environmental factors on the analysis like temperature and humidity have been considered. The strain field has been calculated in...
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Infinite systems of hyperbolic functional differential equations. Ukr.Mat. Zurn.*2003 t. 55 nr 12 s. 1678-1696 bibliogr. 21 poz. Nieskończone układy hiperboliczne równań różniczkowo-funkcyjnych.
PublicationWykazano istnienie prawie klasycznego rozwiązania zagadnienia Cauchy´ego.Dowód wykorzystuje metodę bicharakterystyk i nierówności całkowo-funkcyjne.
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The nonlinear effects of sound in a liquid with relaxation losses
PublicationThe nonlinear effects of sound in electrolyte with a chemical reaction are examined. The dynamic equations that govern non-wave modes in the field of intense sound are derived, and acoustic forces of vortex, entropy, and relaxation modes are determined in the cases of low-frequency sound and high-frequency sound. The difference in the nonlinear effects of sound in electrolyte and in a gas with excited vibrational degrees of molecules,...
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Dynamic Behavior of Aluminum Alloy Aw 5005 Undergoing Interfacial Friction and Specimen Configuration in Split Hopkinson Pressure Bar System at High Strain Rates and Temperatures
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Critical perspectives on media architecture: is it still possible to design projects without negatively affecting urban nighttime environments and will the future remain dynamic, bright and multi-colored?
PublicationNowadays, due to advances in electrical devices, new digital media, lighting, information and communication technologies, cities are being used 24/7. The paper discusses critical aspects of Media Architecture in the context of public spaces as well as urban nighttime environments from the perspective of a practising lighting architect. The author examines recent issues of negative design approaches and presents proposals for improving...
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Exact resultant equilibrium conditions in the non-linear theory of branching and self-intersecting shells
PublicationWe formulate the exact, resultant equilibrium conditions for the non-linear theory of branching and self-intersecting shells. The conditions are derived by performing direct through-the-thickness integration in the global equilibrium conditions of continuum mechanics. At each regular internal and boundary point of the base surface our exact, local equilibrium equations and dynamic boundary conditions are equivalent, as expected,...
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Laplace domain BEM for anisotropic transient elastodynamics
PublicationIn this paper, we describe Laplace domain boundary element method (BEM) for transient dynamic problems of three-dimensional finite homogeneous anisotropic linearly elastic solids. The employed boundary integral equations for displacements are regularized using the static traction fundamental solution. Modified integral expressions for the dynamic parts of anisotropic fundamental solutions and their first derivatives are obtained....
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Efficiency of acoustic heating in the Maxwell fluid
PublicationThe nonlinear effects of sound in a fluid describing by the Maxwell model of the viscous stress tensor is the subject of investigation. Among other, viscoelastic biological media belong to this non-newtonian type of fluids. Generation of heating of the medium caused by nonlinear transfer of acoustic energy, is discussed in details. The governing equation of acoustic heating is derived by means of the special linear combination...
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Efficiency of acoustic heating in the Maxwell fluid
PublicationThe nonlinear effects of sound in a fluid describing by the Maxwell model of the viscous stress tensor is the subject of investigation. Among other, viscoelastic biological media belong to this non-newtonian type of fluids. Generation of heating of the medium caused by nonlinear transfer of acoustic energy, is discussed in details. The governing equation of acoustic heating is derived by means of the special linear combination...
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On the generalized model of shell structures with functional cross-sections
PublicationIn the present study, a single general formulation has been presented for the analysis of various shell-shaped structures. The proposed model is comprehensive and a variety of theories can be used based on it. The cross-section of the shell structure can be arbitrarily analyzed with the presented equations. In other words, various types of shell structures, including cylindrical, conical, spherical, elliptical, hyperbolic, parabolic,...
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Control of mass concentration of reagents by sound in a gas with nonequilibrium chemical reactions
PublicationThe weakly nonlinear dynamics of a chemically reacting gas is studied. Nonlinear interaction of acoustic and nonacoustic types of motion are considered. We decompose the base equations using the relationships of the gas-dynamic perturbations specific for every type of motion. The governing equation for the mass fraction of a reagent influenced by dominating sound is derived and discussed. The conclusions concern the equilibrium...
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MAGNETOACOUSTIC HEATING AND STREAMING IN A PLASMA WITH FINITE ELECTRICAL CONDUCTIVITY
PublicationNonlinear effects of planar and quasi-planar magnetosound perturbations are discussed. Plasma is assumed to be an ideal gas with a finite electrical conductivity permeated by a magnetic filed orthogonal to the trajectories of gas particles. the excitation of non-wave modes in the filed of intense magnetoacoustic perturbations, i.e., magnetoaciustic heating and streaming, is discussed. The analysis includes a derivation if instantaneous...
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A comparative analysis of numerically simulated and experimentally measured static responses of a floating dock
PublicationTwo numerical methods, dynamic and static analyses, are proposed to calculate the static responses of a floating dock under different ballast water distributions. Model-scale experimental tests were conducted to compare with these numerical methods. The dynamic analysis includes a 6-degree-of-freedom (6-DOF) model, a hydrostatic force model and a hydrodynamic force model to simulate the dock's freely floating processes. The dock's...
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Modelling of joining route segments of differential curvature
PublicationThe paper presents a new general method of modelling route segments curvature using differential equations. The method enables joining of route segments of different curvature. Transitional curves of linear and nonlinear curvatures have been identified in the case of joining two circular arcs by S-shaped and C-oval transitions. The obtained S-shaped curves have been compared to the cubic C-Bezier curves and to the Pythagorean hodograph...
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SU‐GG‐T‐286: Performance of An Improved Optical Computed Tomography Polymer Gel Dosimeter System for 3‐D Dose Verification of Static and Dynamic Phantom Deliveries
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