167 research outputs found
Sequential Monte Carlo applied to virtual flow meter calibration
Soft-sensors are gaining popularity due to their ability to provide estimates
of key process variables with little intervention required on the asset and at
a low cost. In oil and gas production, virtual flow metering (VFM) is a popular
soft-sensor that attempts to estimate multiphase flow rates in real time. VFMs
are based on models, and these models require calibration. The calibration is
highly dependent on the application, both due to the great diversity of the
models, and in the available measurements. The most accurate calibration is
achieved by careful tuning of the VFM parameters to well tests, but this can be
work intensive, and not all wells have frequent well test data available. This
paper presents a calibration method based on the measurement provided by the
production separator, and the assumption that the observed flow should be equal
to the sum of flow rates from each individual well. This allows us to jointly
calibrate the VFMs continuously. The method applies Sequential Monte Carlo
(SMC) to infer a tuning factor and the flow composition for each well. The
method is tested on a case with ten wells, using both synthetic and real data.
The results are promising and the method is able to provide reasonable
estimates of the parameters without relying on well tests. However, some
challenges are identified and discussed, particularly related to the process
noise and how to manage varying data quality.Comment: 20 pages, 12 figures, and 3 table
Personalized smart environments to increase inclusion of people with Down's Syndrome
Most people with Downs Syndrome (DS) experience low integration with society. Recent research and new opportunities for their integration in mainstream education and work provided numerous cases where levels of achievement exceeded the (limiting) expectations. This paper describes a project, POSEIDON, aiming at developing a technological infrastructure which can foster a growing number of services developed to support people with DS. People with DS have their own strengths, preferences and needs so POSEIDON will focus on using their strengths to provide support for their needs whilst allowing each individual to personalize the solution based on their preferences. This project is user-centred from its inception and will give all main stakeholders ample opportunities to shape the output of the project, which will ensure a final outcome which is of practical usefulness and interest to the intended users
Bayesian Neural Networks for Virtual Flow Metering: An Empirical Study
Recent works have presented promising results from the application of machine
learning (ML) to the modeling of flow rates in oil and gas wells. Encouraging
results and advantageous properties of ML models, such as computationally cheap
evaluation and ease of calibration to new data, have sparked optimism for the
development of data-driven virtual flow meters (VFMs). Data-driven VFMs are
developed in the small data regime, where it is important to question the
uncertainty and robustness of models. The modeling of uncertainty may help to
build trust in models, which is a prerequisite for industrial applications. The
contribution of this paper is the introduction of a probabilistic VFM based on
Bayesian neural networks. Uncertainty in the model and measurements is
described, and the paper shows how to perform approximate Bayesian inference
using variational inference. The method is studied by modeling on a large and
heterogeneous dataset, consisting of 60 wells across five different oil and gas
assets. The predictive performance is analyzed on historical and future test
data, where an average error of 4-6% and 8-13% is achieved for the 50% best
performing models, respectively. Variational inference appears to provide more
robust predictions than the reference approach on future data. Prediction
performance and uncertainty calibration is explored in detail and discussed in
light of four data challenges. The findings motivate the development of
alternative strategies to improve the robustness of data-driven VFMs.Comment: 34 pages, 11 figure
Have medical studentsâ attitudes towards clinical communication skills changed over a 12- year period? A comparative long-term study
Background
Attitudes towards learning clinical communication skills at the end of medical school are likely to reflect the studentsâ training and motivation for the continued development of their skills as doctors. Students from two Norwegian medical schools, one with a traditional, and the other with an integrated curriculum, were approached in 2003 and 2015; with regard to changes in studentsâ attitudes towards acquiring communication skills in two diverse learning environments. This comparison might reveal the effects of the training programs from a long-term perspective, as neither of the medical schools made any major curriculum changes within the study period.
Methods
The samples comprised final-year medical students. Two separate cross-sectional surveys performed 12âyears apart (2003 and 2015) used items from the Communication Skills Attitude Scale in addition to age and gender. The traditional curriculum included only theoretical teaching and no contact with patients was made during the first 2 to 2.5âyears of medical school. However, the integrated curriculum combined training in theoretical and clinical communication skills with early patient contact from the beginning.
Results
Attitudes improved from the first to the second survey at both schools, however, students from the integrated school reported more positive attitudes than those from the traditional school. Female students from the integrated school contributed the most to the difference in attitudes in both surveys.
Conclusions
Students in both traditional and integrated curricula improved their attitudes from the first to the second assessment. However, compared with the traditional curriculum, the integrated one fostered even higher levels of positive attitudes towards acquiring communication skills, and a pronounced influence was observed on female students. These findings suggest that an educational program with greater emphasis on improving attitudes among male students may be required.publishedVersio
Assessing medical students' attitudes towards learning communication skills â which components of attitudes do we measure?
BACKGROUND: The Communication Skills Attitudes Scale (CSAS) created by Rees, Sheard and Davies and published in 2002 has been a widely used instrument for measuring medical students' attitudes towards learning communication skills. Earlier studies have shown that the CSAS mainly tests two dimensions of attitudes towards communication; positive attitudes (PAS) and negative attitudes (NAS). The objectives of our study are to explore the attitudes of Norwegian medical students towards learning communication skills, and to compare our findings with reports from other countries. METHODS: The CSAS questionnaire was mailed simultaneously to all students (n = 3055) of the four medical schools in Norway in the spring of 2003. Response from 1833 students (60.0%) were analysed by use of SPSS ver.12. RESULTS: A Principal component analysis yielded findings that differ in many respects from those of earlier papers. We found the CSAS to measure three factors. The first factor describes students' feelings about the way communication skills are taught, whereas the second factor describes more fundamental attitudes and values connected to the importance of having communication skills for doctors. The third factor explores whether students feel that good communication skills may help them respecting patients and colleagues. CONCLUSION: Our findings indicate that in this sample the CSAS measures broader aspects of attitudes towards learning communication skills than the formerly described two-factor model with PAS and NAS. This may turn out to be helpful for monitoring the effect of different teaching strategies on students' attitudes during medical school
Curriculum factors influencing knowledge of communication skills among medical students
Background
Communication training builds on the assumption that understanding of the concepts related to professional communication facilitates the training. We know little about whether students' knowledge of clinical communication skills is affected by their attendance of communication training courses, or to what degree other elements of the clinical training or curriculum design also play a role. The aim of this study was to determine which elements of the curriculum influence acquisition of knowledge regarding clinical communication skills by medical students.
Methods
The study design was a cross-sectional survey performed in the four Norwegian medical schools with different curricula, spring 2003. A self-administered questionnaire regarding knowledge of communication skills (an abridged version of van Dalen's paper-and-pencil test) was sent to all students attending the four medical schools. A total of 1801 (59%) students responded with complete questionnaires.
Results
At the end of the 1st year of study, the score on the knowledge test was higher in students at the two schools running communication courses and providing early patient contact (mean 81%) than in the other two medical schools (mean 69â75%, P †0.001), with students studying a traditional curriculum scoring the lowest. Their scores increased sharply towards the end of the 3rd year, during which they had been subjected to extensive patient contact and had participated in an intensive communication course (77% vs. 72% the previous year, P †0.01). All students scored generally lower in academic years in which there was no communication training. However, at the end of the final year the difference between the schools was only 5% (81% vs. 86%, P †0.001).
Conclusion
The acquisition of knowledge regarding communication skills by medical students may be optimised when the training is given together with extensive supervised patient contact, especially if this teaching takes place in the initial years of the curriculum
A multidisciplinary program of preparation for childbirth and motherhood: maternal anxiety and perinatal outcomes
Background: To study maternal anxiety and perinatal outcomes in pregnant women submitted to a Multidisciplinary Program for Childbirth and Motherhood Preparation (MPCM).Methods: This is a not randomized controlled trial on 67 nulliparous pregnant women divided into two groups according to participation (MPCM Group; n = 38) or not (Control Group; n = 29) in MPCM. the program consisted of 10 meetings (between the 18th and the 38th gestational week) during which educational, physiotherapeutic and interaction activities were developed. Anxiety was quantified at the beginning and at the end of the gestational period by the Trace-State Anxiety Inventory (STAI).Results: Initial maternal anxiety was equivalent between the groups. At the end of the gestational period, it was observed that anxiety levels increased in the Control Group and were maintained in the MPCM Group. A higher occurrence of vaginal deliveries (83.8%) and hospital discharge of three-day-older newborns (81.6%) as a result of MPCM was also significant. Levels of state-anxiety at the end of pregnancy showed a negative correlation with vaginal delivery, gestational age, birth weight and Apgar index at the first minute and positive correlation with the hospital period remaining of the newborns.Conclusion: in the study conditions, MPCM was associated with lower levels of maternal anxiety, a larger number of vaginal deliveries and shorter hospitalization time of newborns. It was not related to adverse perinatal outcomes.Coordenação de Aperfeiçoamento de Pessoal de NĂvel Superior (CAPES)Univ Estadual Paulista, Botucatu Sch Med, Dept Neurol Psychol & Psychiat, Botucatu, SP, BrazilUniv Estadual Paulista, Botucatu Sch Med, Dept Gynecol & Obstet, Botucatu, SP, BrazilUniv Sagrado Coracao, Dept Hlth Sci, Physiotherapy Sch, Bauru, BrazilSĂŁo Paulo Fed Univ Unifesp, Dept Hlth Sci, Phys Therapy Program, Santos, BrazilSĂŁo Paulo Fed Univ Unifesp, Dept Hlth Sci, Phys Therapy Program, Santos, BrazilWeb of Scienc
Observed communication skills: how do they relate to the consultation content? A nation-wide study of graduate medical students seeing a standardized patient for a first-time consultation in a general practice setting
<p>Abstract</p> <p>Background</p> <p>In this study, we wanted to investigate the relationship between background variables, communication skills, and the bio-psychosocial content of a medical consultation in a general practice setting with a standardized patient.</p> <p>Methods</p> <p>Final-year medical school students (N = 111) carried out a consultation with an actor playing the role of a patient with a specific somatic complaint, psychosocial stressors, and concerns about cancer. Based on videotapes, communication skills and consultation content were scored separately.</p> <p>Results</p> <p>The mean level of overall communication skills had a significant impact upon the counts of psychosocial issues, the patient's concerns about cancer, and the information and planning parts of the consultation content being addressed. Gender and age had no influence upon the relationship between communication skills and consultation content.</p> <p>Conclusion</p> <p>Communication skills seem to be important for final-year students' competence in addressing sensitive psychosocial issues and patients' concerns as well as informing and planning with patients being representative for a fairly complex case in general practice. This result should be considered in the design and incorporation of communication skills training as part of the curriculum of medical schools.</p
Effect of an institutional development plan for user participation on professionals' knowledge, practice, and attitudes. A controlled study
The matter power spectrum in redshift space using effective field theory
The use of Eulerian 'standard perturbation theory' to describe mass assembly in the early universe has traditionally been limited to modes with k <= 0.1 h/Mpc at z=0. At larger k the SPT power spectrum deviates from measurements made using N-body simulations. Recently, there has been progress in extending the reach of perturbation theory to larger k using ideas borrowed from effective field theory. We revisit the computation of the redshift-space matter power spectrum within this framework, including for the first time for the full one-loop time dependence. We use a resummation scheme proposed by Vlah et al. to account for damping of the baryonic acoustic oscillations due to large-scale random motions and show that this has a significant effect on the multipole power spectra. We renormalize by comparison to a suite of custom N-body simulations matching the MultiDark MDR1 cosmology. At z=0 and for scales k <~ 0.4 h/Mpc we find that the EFT furnishes a description of the real-space power spectrum up to ~ 2%, for the ell=0 mode up to ~ 5% and for the ell = 2, 4 modes up to ~ 25%. We argue that, in the MDR1 cosmology, positivity of the ell = 0 mode gives a firm upper limit of k ~ 0.74 h/Mpc for the validity of the one-loop EFT prediction in redshift space using only the lowest-order counterterm. We show that replacing the one-loop growth factors by their Einstein-de Sitter counterparts is a good approximation for the ell = 0 mode, but can induce deviations as large as 2% for the ell = 2, 4 modes. An accompanying software bundle, distributed under open source licenses, includes Mathematica notebooks describing the calculation, together with parallel pipelines capable of computing both the necessary one-loop SPT integrals and the effective field theory counterterms
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