Motion Correction Using Deep Learning Neural Networks - Effects of Data Representation

An in-silico investigation of the effects of ultrasound data representation on the accuracy of the motion prediction made using deep learning neural networks was carried out. The representations studied include: linear (‘envelope’), log compressed, linear with phase and log compressed with phase. A UNet model was trained to predict non-rigid deformation field using a fixed and a moving image pair as the input. The results illustrate that the choice of the representation plays an important role on the accuracy of motion estimation. Specifically, representations with phase information outperform the representations without phase. Furthermore, log-compressed data yielded predictions with higher accuracy than the linear data

SIMULATION AND CALCULATION OF CRITICAL ROTATION FREQUENCY OF ROTORS IN ANSYS WORKBENCH IN 3D APPROACH

This paper presents a comparison of the results of calculating the critical rotation frequency of rotors performed in two different software packages and verification of calculations with experimental data

I NVESTIGATION ОЕ THE CAUSES ОЕ THE DEEECT USING EINITE ELEMENT ANALYSIS IN SOLVING PROBLEMS OE ROTOR DYNAMICS

This paper shows the necessity of 3D calculation of the critical rotation frequency in “rotor + stator” approach on the example of a defect of a real installation

FEMTO-LASER-ASSISTED SURGERY OF CONGENITAL CATARACT IN CHILDREN

Background. The qualitative anterior capsulorhexis in cataract surgery in children with intraocular lens implantation is an important and crucial moment. Difficulties in carrying out capsulorhexis arise from the structural features of the lens capsule at this age. A search of new methods of the capsulorhexis formation in congenital cataract surgery with a more predictable result is an actual problem.Purpose. To study an effectiveness and a safety of the femtosecond laser in cataract surgery in children.Material and methods. The study was conducted in 29 children (30 eyes) with congenital cataracts aged from 2 to 6 years. In the group I the femtolaser capsulorhexis followed by aspiration-irrigation and IOL implantation was used in 14 children (15 eyes). In the group II, 15 children (15 eyes) underwent the manual circular continuous capsulorhexis followed by aspiration-irrigation of congenital cataract and lens implantation. The uncorrected visual acuity (UCVA) preoperatively in both (I and II) groups averaged 0.03±0.01 and 0.08±0.01, respectively.Results. In patients of the group I the femtolaser stage was unremarkable. Single subconjunctival microhemorrages were observed in 46.6% of the cases in the contact area of the vacuum ring. In 4 (26.6%) eyes after femtosecond capsulotomy a constriction of the pupil was observed.A centered anterior capsulorhexis of perfect round shape was obtained in all patients of the group I. In assessing the capsulorhexis diameter a slight increase around 100-200 microns was found intraoperatively. Single bridges that did not affect the shape, location and size of the capsulotomy were revealed during the removal of capsular flap in one case. During the manual capsulorhexis there was a tendency to runaway without going to the posterior capsule and the formation of a slightly decentered and oval capsulorhexis in patients of group II in 7 cases. Improvement of visual acuity was noted on the first day after surgery in both groups (p<0.001). The UCVA in the groups I and II on the first day after surgery was 0.3±0.04 and 0.1±0.05, respectively.Conclusions. Automated capsulorhexis with a femtosecond laser in congenital cataract surgery in children allows to exclude technical accuracy errors of this procedure and to obtain a optimal capsular fixation of the IOL, making the procedure technique more safe

EFFECT OF THE TORQUE COMPLIANCE IN BOLTED FLANGE JOINTS ON THE CRITICAL ROTATION FREQUENCY OF THE ROTOR

In this paper, the effect of torque compliance in bolted flange joints on the critical rotation frequency is consi¬dered for a single rotor and for the associated rotor system of aviation GTE

Thermodynamic interpolation for the simulation of two-phase flow of non-ideal mixtures

This paper describes the development and application of a technique for the rapid interpolation of thermodynamic properties of mixtures for the purposes of simulating two-phase flow. The technique is based on adaptive inverse interpolation and can be applied to any Equation of State and multicomponent mixture. Following analysis of its accuracy, the method is coupled with a two-phase flow model, based on the homogeneous equilibrium mixture assumption, and applied to the simulation of flows of carbon dioxide (CO2) rich mixtures. This coupled flow model is used to simulate the experimental decompression of binary and quinternary mixtures. It is found that the predictions are in good agreement with the experimental data and that the interpolation approach provides a flexible, robust means of obtaining thermodynamic properties for use in flow models

Heavy oil recovery efficiency using SAGD, SAGD with propane co-injection and STRIP-SAGD

Primary oil recovery methods in heavy oil basins generally extract 5-10% of the available resource, with the vast majority left in the ground and recoverable only through Enhanced Oil Recovery (EOR) methods. Traditional EOR methods, such as SAGD and solvent-assisted SAGD, generate steam in surface facilities and inject it underground to mobilize the oil for production. However, these methods can have considerable energy losses that significantly impact process performance. In contrast, the Solvent Thermal Resource Innovation Process (STRIP) technology, which uses down hole combustion of methane to produce CO2 and steam, reduces the operating and capital costs of surface facilities, saving more than 50% of the energy typically required for thermal production. In this work, simulations of conventional SAGD, SAGD with a non-condensing solvent (propane), and STRIP-SAGD for a typical bitumen reservoir in the Fort McMurray region in Alberta, Canada were performed using the combined software system ADGPRS/GFLASH. SAGD simulations used steam injection with a quality of 0.8 while STRIP simulations injected a vapor-liquid mixture with a quality of 0.8. Furthermore, both solvent-based EOR methods required longer operation periods than conventional SAGD to recover a similar amount of oil. However, when compared on the basis of cumulative oil produced for the same overall energy input, it is shown that STRIP-SAGD recovered more oil per kJ of energy input to the reservoir than either SAGD or SAGD with propane co-injection

High performance framework for modelling of complex subsurface flow and transport applications

Numerical modelling of multiphase multicomponent flow coupled with mass and energy transport in porous media is crucially important for many applications including oil recovery, carbon storage and geothermal. To deliver robust simulation results, a fully or adaptive implicit method is usually employed, creating a highly nonlinear system of equations. It is then solved with the Newton-Raphson method, which requires a linearization procedure to assemble a Jacobian matrix. Operator Based Linearization (OBL) approach allows detaching property computations from the linearization stage by using piece-wise multilinear approximations of state-dependent operators related to complex physics. The values of operators used for interpolation are computed adaptively in the parameter-space domain, which is uniformly discretized with the desired accuracy. As the result, the simulation performance does not depend on the cost of property computations, making it possible to use expensive equation-of-state formulations (e.g., fugacity-activity thermodynamic models) or even black-box chemical packages (e.g., PHREEQC) for an accurate representation of governing physics without penalizing runtime. On the other hand, the implementation of the simulation framework is significantly simplified, which allows improving the simulation performance further by executing the complete simulation loop on GPU architecture. The integrated open-source framework Delft Advanced Research Terra Simulator (DARTS) is built around the OBL concept and provides a flexible, modular and computationally efficient modelling package. In this work, we evaluate the computational performance of DARTS for various subsurface applications of practical interests on both CPU and GPU platforms. We provide a detailed performance comparison of particular workflow pieces composing Jacobian assembly and linear system solution, including both stages of Constrained Pressure Residual solver.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Reservoir Engineerin

Fully Compositional and Thermal Reservoir Simulations Efficiently Compare EOR Techniques

Primary oil recovery methods in Saskatchewan\u27s heavy oil basin extract 5 to 10% of the available resource with the vast majority left in the ground and recoverable only through Enhanced Oil Recovery (EOR) methods. Traditional EOR generates steam in surface facilities and injects it underground to mobilize the oil for production with considerable energy losses inherent in the process. R.I.I. North America\u27s Solvent Thermal Resource Innovation Process (STRIP) technology moves the steam generator underground, reducing the operating and capital costs of a surface thermal production facility by 30% and 50% respectively, and saving more than 30% of the energy typically required for thermal production. STRIP technology combusts methane to produce in situ CO 2 and steam. Because CO2 acts as a co-solvent, STRIP outperforms traditional steam-injection technology. This is demonstrated using a breakthrough modeling technique that couples fully compositional and thermal reservoir flow simulation capabilities. This new approach couples FlashPoint\u27s equation-of-state solver for the multiphase, multi-component, isothermal, isobaric flash problem, GFLASH, with Stanford\u27s Automatic Differentiation General Purpose Research Simulator for thermal reservoir flow simulations. This new computational framework exploits advanced techniques for skipping phase-identification computations and only uses exact phase equilibria from GFLASH when needed, reducing computational times by one to two orders of magnitude compared to the full rigorous solution. Copyright 2013, Society of Petroleum Engineers