4,512 research outputs found
Gas-Liquid Two-Phase Flow Measurement With Throat-Extended Venturi Meter Based on Differential Pressure Ratios and Fluctuations
No full textThis article presents a novel approach to measuring gas-liquid two-phase flow (GLTPF) using a throat-extended Venturi meter (TEVM) based on differential pressure (DP) ratios and fluctuations. The over-reading (OR) and mass quality are the dominant parameters for accurate mass flow rate measurement by a TEVM. First, a liquid OR model is established based on multiple DP ratios (DPRs), gas-to-liquid density ratio (GLDR), and liquid densitometric Froude number. This model is solved by integrating a deep neural network (DNN) with an iterative optimization technique. Subsequently, a mass quality model is developed based on multi-DP fluctuations and other related parameters, which can also be solved using a DNN. Finally, the liquid and gas mass flow rates are obtained sequentially from the preceding results. The proposed method addresses the issue of significant errors in the direct solution of the conventional dual-parameter measurements. It utilizes both the static and dynamic features of multi-DP to achieve the simultaneous measurement of gas and liquid mass flow rates using a single TEVM. The experiment was conducted within a gas flow rate range of 1.3x10(-4)similar to 5.1x10(-3) kg/s, and a liquid flow rate range of 1.12 similar to 3.95 kg/s. The results demonstrate that the relative error for liquid and gas mass flow rates is within +/- 3% and +/- 10%, respectively. This indicates that the proposed method is a cost-effective and viable solution for GLTPF metering using a TEVM, and it can be further adapted to other experimental conditions
Calculation of vapor-liquid equilibrium and PVTx properties of geological fluid system with SAFT-LJ EOS including multi-polar contribution. Part III. Extension to water-light hydrocarbons systems
No full textInternational audienceThe SAFT-LJ EOS improved by Sun and Dubessy (2010, 2012) is extended to water-light hydrocarbon systems. Light hydrocarbons (including CH4, C2H6, C3H8 and nC(4)H(10)) are modeled as chain molecules without multi-polar moments. The contributions of the shape of molecules and main intermolecular interactions existing in water-light hydrocarbon systems (including repulsive and attractive forces between Lennard-Jones segments, the hydrogen-bonding force and the multi-polar interaction between water molecules) to the residual Helmholtz energy were accounted for by this EOS. The adjustable parameters for the interactions of H2O-CH4, H2O-C2H6, H2O-C3H8, and H2O-nC(4)H(10) pairs were evaluated from mutual solubility data of binary water-hydrocarbon systems at vapor-liquid equilibria. Comparison with the experimental data shows this SAFT-LJ EOS can represent well vapor-liquid (and liquid-liquid) equilibria of binary water-light hydrocarbon systems over a wide P-T range. The accuracy of this EOS for mutual solubilities of methane, ethane, propane and water is within the experimental uncertainty generally. Moreover, the model is able to accurately predict the vapor-liquid equilibria and PVTx properties of multi-component systems composed of water, light hydrocarbon as well as CO2. As we know, this EOS is the first one allowing quantitative calculation of the mutual solubilities of water and light hydrocarbons over a wide P-T range among SAFT-type EOSs. This work indicates that the molecular-based EOS combined with conventional mixing rule can well describe the thermodynamic behavior of highly non-ideal systems such as water-light hydrocarbons mixtures except in the critical region for which long range density fluctuations cannot be taken into account by this analytical model
»LJ« Artist book
No full textThe thesis paper deals with the artist book, an art form that has become a part of the university curriculum since the beginning of my university studies. It is most closely connected with the fields of sketch and photography. Both personl sketch and the field of photography have been of particular interest to me during my university years and I prepared an exhibition on the subject, presented by Faculty of Education Gallery. This thesis covers the historical and theoretical background of the artist book and maps the creation of my own artist book, an artistic superaddition titled LJ.
Some of the pioneers of the artist book are also mentioned, including Ed Ruscha, the author of the Twenty Six Gasoline Stations. He was one of the first artist to draw attention to the various artistic possibilities of this art form intertwining different graphic components including sketch, photography, font, paper characteristic, and other visual effects. Franc zagoričnik is presented as a native artist interested in the art form. He was a member of the OHO group, which reached the same conclusions as Ruscha in the 1970s.
The thesis places the artist book within the field of education, since this particular pedagogical approach has been shown to give the pupil freedom of choice and thus enrich his sensibilty to artistic expression. Pratical reasearch was conducted at a high school in Koper, while theoretical research heavily relied on the MGLC library, which is the only Slovene library to carry contemporary literature on this particular art form
"a priori" Dietary Patterns and Cognitive Function in the SUN Project
No full textObjectives: To study and compare associations of 5 dietary patterns-Mediterranean dietary pattern (MDP), Dietary Approaches to Stop Hypertension (DASH), Mediterranean-DASH Intervention for Neurodegenerative delay (MIND), Alternative Healthy Eating Index (AHEI-2010), and a pro-vegetarian diet (PVD)-with cognitive function. Patients and Methods: A subgroup of 806 participants from the "Seguimiento Universidad de Navarra"(SUN) cohort of university graduates, >55 years old, was interviewed with the validated Spanish Telephone Interview for Cognitive Status (STICS-m) at baseline and after 2 and 6 years. For recruitment to the SUN cohort, participants completed a validated food-frequency questionnaire to calculate dietary adherence scores. These scores were used as independent variables in linear regression models (a model for each dietary pattern) to assess their association with the 6-year change in STICS-m as the dependent variable. Linear mixed models were also fitted to compare trajectories of STICS-m scores. All models were adjusted for relevant confounding factors. Results: Adjusted differences showed advantages in the 6-year change in STICS-m score of 0.25 (95% CI 0.04-0.45) for an increase of 1-SD (9 points) in the AHEI-2010 and of 0.27 (95% CI 0.05-0.48) for an increase of 1-SD (1.5 points) in the MIND diet. The MDP, DASH, and PVD scores yielded positive differences in their point estimates for an increase in 1-SD, but results were not statistically significant. The MIND diet appeared to modify changes in cognitive function over time. Conclusions: Our results showed a beneficial association between the MIND diet and cognitive function and suggested a benefit for the AHEI-2010 pattern. Results for the MDP, DASH, and PVD were inconclusive
Correction to: Photoacoustic Measurements of the Thermal and Elastic Properties of n-Type Silicon Using Neural Networks (Silicon, (2020), 12, 6, (1289-1300), 10.1007/s12633-019-00213-6)
No full textThe original version of the article unfortunately contained an error. © 2020, Springer Nature B.V.
The author name ‘Кatarina Lj. Djordjevic’ was inadvertently
captured twice. The correct author group is shown above.Link to the corrected article: [https://vinar.vin.bg.ac.rs/handle/123456789/8759
Episodic encoding is more than the sum of its parts: An fMRI investigation of multifeatural contextual encoding
No full textEpisodic memories are characterized by their contextual richness, yet little is known about how the various features comprising an episode are brought together in memory. Here we employed fMRI and a multidimensional source memory procedure to investigate processes supporting the mnemonic binding of item and contextual information. Volunteers were scanned while encoding items for which the contextual features (color and location) varied independently, allowing activity elicited at the time of study to be segregated according to whether both, one, or neither feature was successfully retrieved on a later memory test. Activity uniquely associated with successful encoding of both features was identified in the intra-parietal sulcus, a region strongly implicated in the support of attentionally mediated perceptual binding. The findings suggest that the encoding of disparate features of an episode into a common memory representation requires that the features be conjoined in a common perceptual representation when the episode is initially experienced
Persistent truncus arteriosus: twenty years experience in a tertiary care center in Taiwan
No full textBehaviour of caregivers to protect their infants from exposure to the sun in Queensland, Australia.
No full textExposure to the sun by infants has been demonstrated to increase the risk of the development of melanoma and other skin cancers later in life. A cohort of 508 women who delivered healthy Caucasian babies were followed up at 1 year to determine their knowledge, attitudes and practices regarding sun protection towards themselves and their child. In addition, the 1-year-old infants were assessed by a trained nurse for the number of nevi they had on their skin. Results indicate caregivers reported a high level of sun-protection practices towards their child, with 93% of the caregivers reporting usually or always placing the child in the shade when going outside. Further, 81% of the caregivers reported usually or always placing a hat on the child, while 64% reported usually or always applying sunscreen to the child's exposed skin. Interestingly, only 61% of the caregivers reported that they stayed in the shade to reduce sun exposure and only 42% wore a hat when out in the sun. Mother's own personal sun-protection methods predicted the method of sun protection that she would most likely use for the child. While children appear to be reasonably protected from the sun, they are influenced by their mother's own behaviors
Radiofrequency ablation of a concealed right anterior accessory pathway associated with right atrial diverticulum in a child.
No full textOn the vapor-liquid equilibrium of attractive chain fluids with variable degree of molecular flexibility
No full textWe study the isotropic (vapor and liquid) phase behavior of attractive chain fluids. Special emphasis is placed on the role of molecular flexibility, which is studied by means of a rod-coil model. Two new equations of state (EoSs) are developed for square-well- (SW) and Lennard-Jones (LJ) chain fluids. The EoSs are developed by applying the perturbation theory of Barker and Henderson (BH) to a reference fluid of hard chain molecules. The novelty of the approach is based on (1) the use of a recently developed hard-chain reference EoS that explicitly incorporates the effects of molecular flexibility, (2) the use of recent molecular simulation data for the radial distribution function of hard-chain fluids, and (3) a newly developed effective segment size, which effectively accounts for the soft repulsion between segments of LJ chains. It is shown that the effective segment size needs to be temperature-, density-, and chain-length dependent. To obtain a simplified analytical EoS, the perturbation terms are fitted by polynomials in density (SW and LJ), chain length (SW and LJ), and temperature (only for LJ). It is shown that the equations of state result in an accurate description of molecular simulation data for vapor-liquid equilibria (VLE) and isotherms of fully flexible SW- and LJ chain fluids and their mixtures. To evaluate the performance of the equations of state in describing the effects of molecular flexibility on VLE, we present new Monte Carlo simulation results for the VLE of rigid linear- and partially flexible SW- and LJ chain fluids. For SW chains, the developed EoS is in a good agreement with simulation results. For increased rigidity of the chains, both theory and simulations predict an increase of the VL density difference and a slight increase of the VL critical temperature. For LJ chains, the EoS proves incapable of reproducing part of these trends.Process and EnergyMechanical, Maritime and Materials Engineerin
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