Electrical Conductivity Based Flow Regime Recognition of Two-phase Flows in Horizontal pipeline

An experimental method of resolving flow regimes by utilizing the conductivity data measured by Electrical Resistance Tomography (ERT) is presented. The method applies Boolean logic and frequency analysis of the ERT signal in order to identify five typical flow regimes in horizontal pipe namely: bubble, plug, slug, stratified and annular. The relative conductivity signal obtained from the tomograms is converted to binary form in order to perform Boolean logical operation with the binary templates of typical flow patterns. The overall conductivity of the tomogram is used to extract frequency information of the flow. Flow pattern is identified by the statistical analysis of the combination of this information. The recognition method was evaluated using experimental data from horizontal pipeline for different flow conditions. The identification of the flow regimes from the method was verified using the conductivity images from ERT

Proper Orthogonal Decomposition as a technique for identifying multiphase flow regime based on Electrical Impedance Tomography

Collecting very large amount of data from experimental measurement is a common practice in almost every scientific domain. There is a great need to have specific techniques capable of extracting synthetic information, which is essential to understand and model the specific phenomena. The Proper Orthogonal Decomposition (POD) is one of the most powerful data-analysis methods for multivariate and nonlinear phenomena. Generally, POD is a procedure that takes a given collection of input experimental or numerical data and creates an orthogonal basis constituted by functions estimated as the solutions of an integral eigenvalue problem known as a Fredholm equation. By utilising POD to identify flow structure in horizontal pipeline, specially, for slag, plug and wavy stratified air-water flow regimes, this paper proposes a novel approach, in which POD technique extends the current evaluation procedure of Electrical Impedance Tomography applied on air-water flow measurement. This extension is provided by implementation of the POD as an identifier of typical horizontal multiphase flow regimes. The POD snapshot matrices are reconstructed for EIT measurement domain and specific flow conditions. Direct POD method introduced by Lumley is applied. It is expected that this study may provide new knowledge on two phase flow dynamics in a horizontal pipeline and supportive information for further prediction of multiphase flow regime

Numerical modelling of gas-liquid flow phenomena in horizontal pipelines

Gas-liquid flows are omnipresent in industrial and environmental processes. Examples are the transportation of petroleum products [1, 2], the cooling of nuclear reactors [3, 4], the operation of absorbers [5], distillation columns [6], gas lift pumps [7] and many mores. Different input parameters induce topologically different flow patterns with different flow character and behaviour [7, 8] . The present study concentrate to diabatic incompressible two-phase flow in horizontal pipeline with separated character [9, 10] (Ugas < 10m/s and Uliquid < 0:2m/s) such as stratified wavy flow regime including typical multiphase instability (Kelvin-elmholtz instability) [11, 12]. The Proper Orthogonal Decomposition (POD) [13], introduced by Lumpay (1967) [14] was used to extract synthetic information essential to understand and to model flow dynamics phenomena. POD in this study are used to identify flow structure in the horizontal pipeline specially under transient of separated flow regimes. The snapshot matrix are reconstruct for specific flow sections and regimes. Present decomposition method, in this case used to analyse CFD data, are originally testing and developing for future using to analyse experimental data obtained by process tomography system [15]

Young professionals for health development: the Kenyan experience in combating non-communicable diseases

Young individuals (below 35 years) comprise an estimated 60% of the global population. Not only are these individuals currently experiencing chronic, non-communicable diseases (NCDs), either living with or at risk for these conditions, but will also experience the long-term repercussions of the current NCD policy implementations. It is thus imperative that they meaningfully contribute to the global discourse and responses for NCDs at the local level. Here, we profile one example of meaningful engagement: the Young Professionals Chronic Disease Network (YPCDN). The YPCDN is a global online network that provides a platform for young professionals to deliberate new and innovative methods of approaching the NCD challenges facing our societies. We provide a case study of the 2-year experiences of a country chapter (Kenya) of the YPCDN to demonstrate the significance and impact of emerging leaders in addressing the new global health agenda of the 21st century

Evaluation of EIT systems and algorithms for handling full void fraction range in two-phase flow measurement

In the aqueous-based two-phase flow, if the void fraction of dispersed phase exceeds 0.25, conventional electrical impedance tomography (EIT) produces a considerable error due to the linear approximation of the sensitivity back-projection (SBP) method, which limits the EIT's wider application in the process industry. In this paper, an EIT sensing system which is able to handle full void fraction range in two-phase flow is reported. This EIT system employs a voltage source, conducts true mutual impedance measurement and reconstructs an online image with the modified sensitivity back-projection (MSBP) algorithm. The capability of the Maxwell relationship to convey full void fraction is investigated. The limitation of the linear sensitivity back-projection method is analysed. The MSBP algorithm is used to derive relative conductivity change in the evaluation. A series of static and dynamic experiments demonstrating the mean void fraction obtained using this EIT system has a good agreement with reference void fractions over the range from 0 to 1. The combination of the new EIT system and MSBP algorithm would significantly extend the applications of EIT in industrial process measurement

The Impact of Using Lean-centered Model to Increase the Achievement of the Learners in English Language Teaching

The suggested Lean centered-model has been designed to increase the achievement of the students in English Language Teaching (ELT). An experimental study was conducted to find the effectiveness of the model in the application of Lean as an innovative method in English language teaching. The participants of the study scored different achievements in both, the control and treatment groups. The end-result of the learners in the experimental group was statistically highly significant in the pre and posttests. The result was also statistically different between the pre-posttests between the two groups. The current model leads the stakeholders of an educational process to finish the syllabus on time,the program finished as it had been planned and resulting a better achievement. The model was a guide to finish the whole program in line with completing every step before starting the next. The lean-centered model helped to meet the needs of the learners. The learners also managed to get high achievements and develop their skills. The students had their roles as theculture of lean allows learners to be an effective part of the process. All the steps were eliminated which existed in the program and added no value to the end-result of the students according to the lean-centered model

Search for chargino-neutralino production with mass splittings near the electroweak scale in three-lepton final states in √s=13 TeV pp collisions with the ATLAS detector

A search for supersymmetry through the pair production of electroweakinos with mass splittings near the electroweak scale and decaying via on-shell W and Z bosons is presented for a three-lepton final state. The analyzed proton-proton collision data taken at a center-of-mass energy of √s=13  TeV were collected between 2015 and 2018 by the ATLAS experiment at the Large Hadron Collider, corresponding to an integrated luminosity of 139  fb−1. A search, emulating the recursive jigsaw reconstruction technique with easily reproducible laboratory-frame variables, is performed. The two excesses observed in the 2015–2016 data recursive jigsaw analysis in the low-mass three-lepton phase space are reproduced. Results with the full data set are in agreement with the Standard Model expectations. They are interpreted to set exclusion limits at the 95% confidence level on simplified models of chargino-neutralino pair production for masses up to 345 GeV

Search for direct stau production in events with two hadronic tau-leptons in root s=13 TeV pp collisions with the ATLAS detector

A search for the direct production of the supersymmetric partners ofτ-leptons (staus) in final stateswith two hadronically decayingτ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of139fb−1, recorded with the ATLAS detector at the LargeHadron Collider at a center-of-mass energy of 13 TeV. No significant deviation from the expected StandardModel background is observed. Limits are derived in scenarios of direct production of stau pairs with eachstau decaying into the stable lightest neutralino and oneτ-lepton in simplified models where the two staumass eigenstates are degenerate. Stau masses from 120 GeV to 390 GeV are excluded at 95% confidencelevel for a massless lightest neutralino

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Investigation of the Structural Properties of Thermally Evaporated Aluminium Thin Films on Different Polymer Substrates.

This paper studies the properties of thermally evaporated 1 μm of aluminium (Al) thin films on polyimide (PI) and polyethylene terephthalate (PET) substrates at room temperature with thermal evaporation in a vacuum of about 3 x 10-5 Torr for use as window materials for solar cells. Effects of substrate types on the structural and electrical characteristics of the films were studied. Sets of experiments were conducted to optimize the deposition of Al films with appropriate deposition parameters. The deposited films were analyzed with atomic force microscopy (AFM), energy dispersive X-ray (EDX), X-ray diffraction (XRD). Energy dispersive X-ray (EDX) spectra shows presence of Al contacts on both PI and PET substrates. X-ray diffraction (XRD) results illustrate proper formation of Al (111) plane at 38.4o with full width at half maximum (FWHM) of 0.1968° on both samples. Atomic force microscope (AFM) images reveal that both samples possess smooth surfaces with surface roughness root mean square (RMS) below 10 nm