Multiphase Test Research Articles

Presurgical Upgrade Prediction of DCIS to Invasive Ductal Carcinoma Using Time-dependent Deep Learning Models with DCE MRI.

Purpose To determine whether time-dependent deep learning models can outperform single time point models in predicting preoperative upgrade of ductal carcinoma in situ (DCIS) to invasive malignancy at dynamic contrast-enhanced (DCE) breast MRI without a lesion segmentation prerequisite. Materials and Methods In this exploratory study, 154 cases of biopsy-proven DCIS (25 upgraded at surgery and 129 not upgraded) were selected consecutively from a retrospective cohort of preoperative DCE MRI in women with a mean age of 59 years at time of diagnosis from 2012 to 2022. Binary classification was implemented with convolutional neural network (CNN)-long short-term memory (LSTM) architectures benchmarked against traditional CNNs without manual segmentation of the lesions. Combinatorial performance analysis of ResNet50 versus VGG16-based models was performed with each contrast phase. Binary classification area under the receiver operating characteristic curve (AUC) was reported. Results VGG16-based models consistently provided better holdout test AUCs than did ResNet50 in CNN and CNN-LSTM studies (multiphase test AUC, 0.67 vs 0.59, respectively, for CNN models [P = .04] and 0.73 vs 0.62 for CNN-LSTM models [P = .008]). The time-dependent model (CNN-LSTM) provided a better multiphase test AUC over single time point (CNN) models (0.73 vs 0.67; P = .04). Conclusion Compared with single time point architectures, sequential deep learning algorithms using preoperative DCE MRI improved prediction of DCIS lesions upgraded to invasive malignancy without the need for lesion segmentation. Keywords: MRI, Dynamic Contrast-enhanced, Breast, Convolutional Neural Network (CNN) Supplemental material is available for this article. © RSNA, 2024.

Determination of accurate baseline representation for three Central Iowa watersheds within a HAWQS-based SWAT analyses

Improving food systems to address food insecurity and minimize environmental impacts is still a challenge in the 21st century. Ecohydrological models are a key tool for accurate system representation and impact measurement. We used a multi-phase testing approach to represent baseline hydrologic conditions across three agricultural basins that drain parts of north central and central Iowa, U.S.: the Des Moines River Basin (DMRB), the South Skunk River Basin (SSRB), and the North Skunk River Basin (NSRB). The Soil and Water Assessment Tool (SWAT) ecohydrological model was applied using a framework consisting of the Hydrologic and Water Quality System (HAWQS) online platform, 40 streamflow gauges, the alternative runoff curve number method, additional tile drainage and fertilizer application. In addition, ten SWAT baselines were created to analyze both the HAWQS parameters (baseline 1) and nine alternative baseline configurations (considering the framework). Most of the models achieved acceptable statistical replication of measured (close to the outlet) streamflows, with Nash-Sutcliffe (NS) values ranging up to 0.80 for baseline 9 in the DMRB and SSRB, and 0.78 for baseline 7 in the NSRB. However, water balance and other hydrologic indicators revealed that careful selection of management data and other inputs are essential for obtaining the most accurate representation of baseline conditions for the simulated stream systems. Using cumulative distribution curves as a criterion, baselines 7 to 10 showed the best fit for the SSRB and NSRB, but none of the baselines accurately represented 20% of low flows for the DMRB. Analysis of snowmelt and growing season periods showed that baselines 3 and 4 resulted in poor simulations across all three basins using four common statistical measures (NS, KGE, Pbias, and R2), and that baseline 9 was characterized by the most satisfactory statistical results, followed by baselines 5, 7 and 1.

АНАЛІЗ ВПЛИВУ МАРШРУТНИХ ТА ЕКСПЛУАТАЦІЙНИХ ФАКТОРІВ НА ТРАНСПОРТНУ ЕНЕРГОЕФЕКТИВНІСТЬ МІСЬКИХ ПАСАЖИРСЬКИХ ПЕРЕВЕЗЕНЬ

The article establishes the relevance of using simulation test methods of technical and technological energy saving and increasing technological competitiveness of motor transport services according to energy criteria when renewing the fleet of buses for urban passenger transportation. It is shown that the existing methodology of bus transport organization does not provide urban passenger bus fleet renewal according to the concept of operational and technological energy saving and improvement of technological competitiveness of automobile transport services. According to the results of multivariate modeling the interrelation between the tasks of formation of energy saving technologies of passenger urban road transport and improvement of the method of technological selection of buses for urban routes with taking into account different (technical, operational and routing) factors. Quantitative dependences of influence of technical, operational and route factors on indexes of transport energy efficiency of transportations and operational intensity of machine procedures of bus transport technologies are received. The object of the research is the energy-consuming process of urban bus transportations taking into account the influence of various factors (technical, operational and route factors). Purpose of work – analysis of route and operational factors influence on transport energy efficiency of urban passenger transportation based on test modeling of bus operation as resource-technical means of motor transport technology. The method of the research is evolution-simulation analysis of transport energy efficiency of transportation and operational intensity of machine procedures of bus transportation technology in multiphase test operations, in which city route network conditions and different factors of bus transportation are taken into account, using software and methods of test-simulation analysis of generalized type vehicles of the NTU Department of Transport Technologies. 407 The results of the article and the method can be implemented by managers of passenger motor transport for long-term management of conceptually oriented development of resource and technological basis of motor transport enterprises and technological processes of bus transportation in cities. KEYWORDS: BUS, URBAN PASSENGER TRANSPORTATION, TRANSPORT ENERGY EFFICIENCY, OPERATIONAL INTENSITY OF MACHINE PROCEDURES, TECHNOLOGY TECHNICAL AND OPERATIONAL FACTORS, EVOLUTIONARY MODELING

"Identification of promising genotypes in varietal trials of sugarcane using deep learning "

Genotypes of varietal trials for identification of promising genotypes of sugarcane undergoes location-based and multiphase testing for both plant and ratoon crop. Identification depends upon analytical studies of data collected from the trials. Data on more than twenty characters such as germination%, tillers, shoots, NMC, fibre, brix, sucrose, CCS, cane yield, etc are collected frequently, starting from germination stage till harvesting at different stages of crop. It is a quite complex and time-consuming task and information about some important parameters may remain unnoticed by experts despite best efforts. Deep learning algorithms can be developed for such complex task to extract high level features from trial data and make intelligent decisions based on it for identifying promising genotypes. Deep learning works on the principle of artificial neural networks in which multiple layers of processing are used to extract progressively higher-level features from data. In this paper, we have demonstrated use of deep learning for identification of promising genotypes. We have developed sequential model using tensorflow libraries in Python programming platform. To construct, train and test deep learning model, datasets of 181 genotypes accepted in coordinated trials of crop improvement programme for the duration 2016-21 have been used. Model uses crop characters viz. cane yield, sucrose%, CCS%, and CCS yield along with score of monitoring and red rot screening. Data management practices allowed to pre-process data for learning and testing model from it. Deep learning in this study consists of input layer, two hidden layers and output layer. Output classes are ’Promising” and “Non-promising” in binary form corresponding to promising genotype or otherwise. Model performed well with accuracy of prediction worked out to be 91.67% with loss value as 0.2832, while F-measure for both promising and non-promising genotypes got a high equivalent score of 0.91 and 0.92 respectively.

A five-equation model based global ale method for compressible multifluid and multiphase flows

In this work, a mixing cell closure model was derived in a Lagrangian formulation based on the hypothesis of isentropic compression or expansion. The proposed closure model is used to construct a five-equation model for the simulation of multifluid and multiphase flows. Thereafter a global ALE(Arbitrary Lagrangian-Eulerian) method was developed for the five-equation model. The five-equation based ALE method is a two-stage ALE method, including a Lagrangian phase and a rezone-remap phase. In the first phase, the model equation was discretized with a cell-centered Lagrangian scheme, and a multifluid Riemann solver was proposed by extending traditional Riemann solver to mixed cells with different materials. The five-equation based ALE method can be used to simulate multi-material flows with large deformation, which is a challenge for many traditional ALE methods. Moreover, it can be used to simulate multiphase flows. A series of multi-material and multiphase test problems were simulated with the five-equation based ALE method, and numerical results agree well with exact solutions and reference results.

Hybrid scheme for complex flows on staggered grids and application to multiphase flows

A hybrid scheme is developed that enables advanced simulations, such as multiphase flows, in complex flow setups with compressible flow solvers using a staggered arrangement of flow variables. For this purpose, a weighted essentially non-oscillatory (WENO) scheme is adapted for staggered grids and combined with a finite difference central scheme. Hybrid weights that maintain continuity in time are computed based on a limiter constructed from the deviation of the local weights from the optimal weights. A total variation diminishing (TVD) interpolation is introduced to avoid numerical oscillations from the flow field. Additionally, the finite difference operators are reformulated in a flux-based finite volume form for convective terms in order to avoid spurious oscillations for turbulent configurations. For demonstrating the accuracy of the newly developed scheme and its improvements compared to the existing schemes, a modified wavenumber analysis is shown. Furthermore, the new scheme is applied to single and multiphase test cases. Finally, it is used for simulating the needle-opening process of a gasoline direct injector (GDI) and predicting the amount of gas inside the nozzle.

Establishing a Global Standard for Wearable Devices in Sport and Fitness: Perspectives from the New England Chapter of the American College of Sports Medicine Members.

The recent explosion of wearable technology and the associated concerns prompted the International Federation of Sports Medicine (FIMS) to create a quality assurance standard for wearable devices, which provides commissioned testing of marketing claims and endorsement of commercial wearables that test favorably. An open forum as announced in the conference advertising was held at the Annual Meeting of the New England Regional Chapter of the American College of Sports Medicine (NEACSM) November 7 to 8, 2019, in Providence, Rhode Island, USA for attending NEACSM members to voice their input on the process. Herein, we report the proceedings. The round table participants perceived the quality assurance standard to be important, but identified some practical process challenges that included the broad scope and complexity of the device universe, the need for a multiphase testing pathway, and the associated fees for product evaluation. The participants also supported the evaluation of device data analysis, behavioral influences, and user experience in the overall evaluation. Looking forward, the FIMS quality assurance standard faces the challenge of balancing these broader perspectives with practical constraints of budget, facilities, time, and human resources.

Study on the Porosity of Saturated Fragmentized Coals during Creep Process and Constitutive Relation

Pore abundance and deformation characteristics of saturated fragmentized coals during creep process are of significant meaning to the study on ground sediment in the mined‐out area. The law of porosity variation of saturated fragmentized coals during creep process and its creep constitutive model were studied by using the self‐developed multiphase coupling creep test device. And, results have indicated that the porosity logarithm of fragmentized coal during creep process shows a linear negative correlation with the time ln(n−a) = −ct + lnb, and the porosity decrease is evidently divided into three phases. In addition, when the stress level is relatively low, the porosity decreases slowly; when the stress level rises up, the porosity decreases quickly; when the stress level remains stable finally, the porosity is smaller. Under the equal stress, as the grain size of fragmentized coals decreases, the porosity tends to decrease, and as the grain size of fragmentized coal tends to be stable, the porosity tends to increase; the creep constitutive equation of fragmentized coals with different grain sizes was established by using the Kelvin–Voigt model, and the correlation analysis shows that the Kelvin–Voigt creep model of fragmentized coals is reasonable.

The Utah Online Dispute Resolution Platform: A Usability Evaluation and Report

This report contains findings and recommendations from usability testing of the State of Utah’s online dispute resolution (ODR) platform. Utah’s ODR platform is a web-based alternative dispute resolution tool that provides parties in small claims debt collection actions with an opportunity to resolve their cases online. The report includes results from a multi-phase testing process designed to engage the low-income community in the review and redesign of Utah’s ODR platform. All testing involved participants who were screened for demographic characteristics that aligned with national data on non-bank personal loan debtors. Two rounds of observation-based usability testing—the first with the existing, baseline platform and the second with a redesigned prototype—yielded data from a total of sixteen participants. Baseline testing revealed that participants experienced significant difficulties with several components of the ODR process, from the summons to settlement. The testing results and the workshops informed the development of an ODR prototype created in Adobe XD, which was evaluated in a second round of observation-based usability testing. Based on the cumulative findings from all tests and workshops, the report recommends the following five changes, which will better align the platform to the needs of its users and facilitate a more successful ODR experience: (1) ease the transition from a paper summons to the platform; (2) streamline the registration process; (3) simplify document sharing and review; (4) improve the help modules; and (5) clarify legal information and user options.

A two-way coupled Euler-Lagrange method for simulating multiphase flows with discontinuous Galerkin schemes on arbitrary curved elements

In this work, we develop a Lagrangian point-particle method to support high-speed dusty flow simulations with discontinuous Galerkin schemes. The carrier fluid is treated in an Eulerian frame through the solution of the compressible Navier-Stokes equations. Particle search and localization is based on the geometric mapping of mesh elements to a reference element and is applicable to arbitrary unstructured, curved, multidimensional grids. High-order interpolation is used to calculate the gas state at a given particle position, and the back-coupling of particles to the carrier fluid is carried out via a simple, effective procedure. Furthermore, we discuss difficulties associated with accounting for particle-wall collisions on curved, high-aspect-ratio elements. We develop a methodology that appropriately handles such collisions and accurately computes post-collision particle trajectories. We first apply the Euler-Lagrange method to one-way coupled tests and show the benefit of using curved instead of straight-sided elements for dealing with particle-wall collisions. We proceed by considering more complex multiphase test cases with two-way coupling, namely dusty flows over a flat plate and through a converging-diverging nozzle. Our final test case consists of hypersonic dusty flow over a sphere in which the target quantity is dust-induced surface heating augmentation at the stagnation point. Quantitative comparisons with experiments are provided.

Принципы аттестации воспроизведения расхода многофазных испытательных стендов

Принципы аттестации воспроизведения расхода многофазных испытательных стендов

Portable and power-free serodiagnosis of Chagas disease using magnetic levitating microbeads.

This work describes the detection of anti-T. cruzi antibodies in whole blood solutions using magnetic levitating microbeads (MLμBs). This simple diagnostic method can be easily performed by minimally trained personnel using an inexpensive and portable magnetic stage that requires no electricity. A multiphase test tube containing the MLμBs facilitates the sequential incubation, filtering, and reading of the immunoassays. The diagnostic method starts by adding a blood sample to the top phase of the test tube where the anti-T. cruzi antibodies present in the blood attach to the T. cruzi antigens on the surface of the MLμBs. Shaking the test tube after incubation mixes the top layer with a paramagnetic medium loaded with SiO2 microcrystals. The attachment of SiO2 microcrystals to those MLμBs bound to T. cruzi antibodies decreases their levitation height once the tube is placed between two antialigned permanent magnets. Measuring the levitation height of MLμBs enables the accurate detection and quantification of anti-T. cruzi antibodies in the blood across the clinically relevant range, with a detection limit of 5 μg mL-1. The small size of the test tubes facilitates the simultaneous analysis of over 50 different samples. MLμBs act as partial collimators for non-polarized light, facilitating their visual identification by the naked eye or by projecting incident light on a thin paper screen. A machine-vision algorithm was created to automatically interpret the results of the MLμB tests from a digital image, resulting in a rapid, accurate, and user-friendly assay for Chagas disease that can be used in resource-limited settings.

The Influence of Multiphase Flow on the Interpretation of Pressure Transient Data in Multilayer Reservoirs With Cross Flow

The authors investigated multiphase flow effects on the analysis of pressure responses in layered reservoirs with cross flow. Virtually all studies on the subject of multiphase well test analysis have been carried out in single-layer reservoirs. However, many reservoirs are found to be composed of number of layers whose characteristics are different from each other and the wells in such reservoirs may be completed and produced from more than one layer. In order to examine the behavior of pressure data in multiphase multilayer reservoirs with interlayer communication several cases are considered. The contrast in phase saturations in each layer is the parameter of interest. For each case the applicability of conventional well test analysis is investigated and reservoir parameters such as phase mobilities, skin factor, and average reservoir pressure are compared with actual values. According to the results of this work, conventional multiphase well test analysis in the single layer reservoir can be used in layered reservoirs with cross flow; however, the data should be interpreted with care if horizontal saturation gradient in the layers is significant.

On the Analysis of Well Test Data Influenced by Capillary Pressure

The focus of this study is on the analysis of capillary pressure effects on well test data. Ignoring the capillary pressure is one of the assumptions that have been applied in all multiphase well test analysis approaches. In this work we investigate the influences of capillary pressure on the analysis of pressure transient data in a solution gas drive reservoir and in a reservoir containing oil and water. Reservoir simulations were performed to generate pressure and saturation data for each case and the pressure responses and the fluids saturation distribution for drawdown and build-up tests for two cases with and without capillary pressure are compared. According to the results of this study, it has been concluded that the influences of capillary pressure on fluids saturation behavior in build-up test due to importance of capillary force than viscose force in this period is more noticeable. Though the effects of capillary pressure lead to differences in the fluids saturation behavior but the authors have not observed dissimilarity in the pressure responses affected by capillary pressure for draw down and build-up test in the both reservoirs under study.

Automated monitoring: a potential solution for achieving sustainable improvement in hand hygiene practices.

Adequate hand hygiene is often considered as the most effective method of reducing the rates of hospital-acquired infections, which are one of the major causes of increased cost, morbidity, and mortality in healthcare. Electronic monitoring technologies provide a promising direction for achieving sustainable hand hygiene improvement by introducing the elements of automated feedback and creating the possibility to automatically collect individual hand hygiene performance data. The results of the multiphase testing of an automated hand hygiene reminding and monitoring system installed in a complex continuing care setting are presented. The study included a baseline Phase 1, with the system performing automated data collection only, a preintervention Phase 2 with hand hygiene status indicator enabled, two intervention Phases 3 and 4 with the system generating hand hygiene reminding signals and periodic performance feedback sessions provided, and a postintervention Phase 5 with only hand hygiene status indicator enabled and no feedback sessions provided. A significant increase in hand hygiene performance observed during the first intervention Phase 3 was sustained over the second intervention Phase 4, with the postintervention phase also indicating higher hand hygiene activity rates compared with the preintervention and baseline phases. The overall trends observed during the multiphase testing, the factors affecting acceptability of the automated hand hygiene monitoring system, and various strategies of technology deployment are discussed.

Two-Phase Flowmeter Based on a Restriction and Gamma Densitometer for Mixtures of Oil and Stratal Water

The design and operating principle of a two-phase flowmeter for mixtures of oil and stratal water based on a restriction and gamma densitometer are presented. Results of tests of the flowmeter on the Multiphase Test Facility of TUV SUD NEL Ltd (Glasgow, Great Britain) are presented. The operating features of the restriction are noted and the compliance of the obtained characteristics of the flowmeter with State Standard requirements is evaluated.

Predicting residual software fault content and their location during multi-phase functional testing using test coverage

Multi-phase functional testing is a common practice which is used in ultra-reliable software development to ensure that no known faults reside in the software to be delivered. In this paper, we present a new test coverage-based model which allows the description of software systems developed through multiple phases of functional testing. This model is further extended: (a) to take advantage of auxiliary observations collected during the multi-phase testing and consequent analysis process to refine the predictions made; (b) to describe software systems where either the initial fault distribution is non-uniform with respect to location, or the repair and test and detection process favour certain locations.

An Overview of Disease-Free Buffalo Breeding Projects with Reference to the Different Systems Used in South Africa

This paper describes the successful national program initiated by the South African government to produce disease-free African buffalo so as to ensure the sustainability of this species due to threats from diseases. Buffalo are known carriers of foot-and-mouth disease, bovine tuberculosis, Corridor disease and brucellosis. A long-term program involving multiphase testing and a breeding scheme for buffalo is described where, after 10 years, a sustainable number of buffalo herds are now available that are free of these four diseases. A large portion of the success was attributable to the use of dairy cows as foster parents with the five-stage quarantine process proving highly effective in maintaining the “disease-free” status of both the calves and the foster cows. The projects proved the successfulness of breeding with African buffalo in a commercial system that was unique to African buffalo and maintained the “wildness” of the animals so that they could effectively be released back into the wild with minimal, if any, behavioral problems.

Effects of non-uniform fluid saturation distribution on pressure transient analysis

Variations of fluid saturation in formation induce unusual trends in pressure transient data, which may cause ambiguities in well test interpretations. Nevertheless, uniform saturation distribution is a common assumption applied in all multiphase well test analysis methods and the effects of fluids saturation changes have not been taken into account in all these approaches. We present a theoretical model which includes non-uniform fluid saturation in pressure transient formulation. The application of the developed model is demonstrated using a simulation of a reservoir containing non-uniform oil and water saturations in the initial condition. This model provides a basis for better interpretation of unusual pressure transient behavior affected by non-uniform saturation distribution.

Prediction of capillary hysteresis in a porous material using lattice-Boltzmann methods and comparison to experimental data and a morphological pore network model

In this work we use two numerical methods which rely only on the geometry and material parameters to predict capillary hysteresis in a porous material. The first numerical method is a morphological pore network (MPN) model, where structural elements are inserted into the imaged pore space to quantify the local capillary forces. Then, based on an invasion–percolation mechanism, the fluid distribution is computed. The second numerical method is a lattice-Boltzmann (LB) approach which solves the coupled Navier–Stokes equations for both fluid phases and describes the dynamics of the fluid/fluid interface. We have developed an optimized version of the model proposed in [Tölke J, Freudiger S, Krafczyk M. An adaptive scheme for LBE multiphase flow simulations on hierarchical grids, Comput. Fluids 2006;35:820–30] for the type of flow problems encountered in this work. A detailed description of the model and an extensive validation of different multiphase test cases have been carried out. We investigated pendular rings in a sphere packing, static and dynamic capillary bundle models and the residual saturation in a sphere packing. A sample of 15 mm in diameter filled with sand particles ranging from 100 to 500 μm was scanned using X-rays from a synchrotron source with a spatial resolution of 11 μm. Based on this geometry we computed the primary drainage, the first imbibition and the secondary drainage branch of the hysteresis loop using both approaches. For the LB approach, we investigated the dependence of the hysteresis loop on the speed of the drainage and the imbibition process. Furthermore we carried out a sensitivity analysis by simulating the hysteretic effect in several subcubes of the whole geometry with extremal characteristic properties. The predicted hysteretic water retention curves were compared to the results of laboratory experiments using inverse modeling based on the Richards equation. A good agreement for the hysteresis loop between the LB and MPN model has been obtained. The primary and secondary drainage of the hysteresis loop of the LB and MPN model compare very well, and also the experimental results fit well with a slight offset of 10% in the amplitude. Differences for the first imbibition have been observed, but also large differences between two different experimental runs have been observed.