Sylvain Mazuel, Chantal de Fouquet, Jean-Paul Chilès, Patrick Goblet, Mohamed Krimissa. Geostatistical modelling for the quantification of uncertainties on the unsatured zone and the groundwater transfer. Groundwater hydraulics in complex environments, Jun 2006, Toulouse, France. pp.2. ⟨hal-00599172⟩ ...

The death of Justice Ruth Bader Ginsburg has cast fresh uncertainty on the fate of the Affordable Care Act as the Supreme Court prepares to hear arguments in a case challenging the constitutionality of the landmark health care law ...

Location: Philadelphia, Pennsylvania , Category: Disparities-focused. Diagnostic uncertainty, the perception of an inability to provide an accurate explanation of the patients health condition, increases the risk of diagnostic error in hospitalized patients if not communicated to families and across healthcare teams. Additionally, differences in clinician-patient communication have been implicated in health disparities in pediatric diagnosis. Improvements in the communication of diagnostic uncertainty have the potential to impact three primary drivers of diagnostic excellence: cognitive performance/diagnostic reasoning, patient/family engagement, and effective teamwork. The Childrens Hospital of Philadelphia will pursue understanding and identifying opportunities for improvement in the communication of diagnostic uncertainty in general pediatric patients admitted from the Emergency Department. Over nine months, they aim for a 20% improvement in the communication of diagnostic uncertainty to ...

TY - JOUR. T1 - Stochastic uncertainty analysis of damage evolution computed through microstructure-property relations. AU - Acar, Erdem. AU - Solanki, Kiran N.. AU - Rais-Rohani, Masoud. AU - Horstemeyer, Mark F.. PY - 2010/4/1. Y1 - 2010/4/1. N2 - Uncertainties in material microstructure features can lead to uncertainty in damage predictions based on multiscale microstructure-property models. This paper presents an analytical approach for stochastic uncertainty analysis by using a univariate dimension reduction technique. This approach is used to analyze the effects of uncertainties pertaining to the structure-property relations of an internal state variable plasticity-damage model that predicts failure. The results indicate that the higher the strain the greater the scatter in damage, even when the uncertainties in the material plasticity and microstructure parameters are kept constant. In addition, the mathematical sensitivity analysis results related to damage uncertainty are consistent ...

TY - JOUR. T1 - Reporting and analyzing statistical uncertainties in Monte Carlo-based treatment planning. AU - Chetty, Indrin J.. AU - Rosu, Mihaela. AU - Kessler, Marc L.. AU - Fraass, Benedick A.. AU - Ten Haken, Randall K.. AU - Kong, Feng Ming (Spring). AU - McShan, Daniel L.. PY - 2006/7/15. Y1 - 2006/7/15. N2 - Purpose: To investigate methods of reporting and analyzing statistical uncertainties in doses to targets and normal tissues in Monte Carlo (MC)-based treatment planning. Methods and Materials: Methods for quantifying statistical uncertainties in dose, such as uncertainty specification to specific dose points, or to volume-based regions, were analyzed in MC-based treatment planning for 5 lung cancer patients. The effect of statistical uncertainties on target and normal tissue dose indices was evaluated. The concept of uncertainty volume histograms for targets and organs at risk was examined, along with its utility, in conjunction with dose volume histograms, in assessing the ...

Classification of multispectral remotely sensed data with textural features is investigated with a special focus on uncertainty analysis in the produced land-cover maps. Much effort has already been directed into the research of satisfactory accuracy assessment techniques in image classification, but a common approach is not yet universally adopted. We look at the relationship between hard accuracy and the uncertainty on the produced answers, introducing two measures based on maximum probability and alpha quadratic entropy. Their impact differs depending on the type of classifier. In this paper, we deal with two different classification strategies, based on support vector machines (SVMs) and Kohonens self-organizing maps (SOMs), both suitably modified to give soft answers. Once the multiclass probability answer vector is available for each pixel in the image, we studied the behavior of the overall classification accuracy as a function of the uncertainty associated with each vector, given a ...

The impacts of the sea-ice characteristics distribution, roughness, temperature and thermal conductivity on an on-ice moving trough in the Fram Strait on 7 March 2002 are investigated. The situation is simulated with the mesoscale transport and fluid model METRAS and the named characteristics are varied within the range of observational uncertainty. The test cases are evaluated against aircraft measurements performed within the Fram Strait Cyclone Experiment 2002. The models sensitivity on the changes in sea-ice characteristics is quantified by statistical means. The strongest impacts on the near-ground temperature are found from sea-ice temperature, manifesting as an overall bias, and the positioning of the sea-ice edge, manifesting as a phase error. Only higher than natural homogenization of the sea-ice cover leads to some reduction of the amplitude error. A reduction of the sea-ice surface roughness is performed by applying an unrealistically small roughness length of z0= 1 mm. This ...

Presently there is no standard for the evaluation of measurement uncertainties for terrestrial laser scanner (TLS) despite the fact that the instrument has been on the market and used for a long time. Since the manufacturers specifications do not always correspond with reality, it is important to have knowledge about how well the instrument performs. Numerous studies over the past decade have applied different approaches to estimate the measurement uncertainties on various TLS.. The purpose of this study was to evaluate and compare the measurement uncertainties of the TLS Leica ScanStation C10 with the multi station Leica Nova MS50 under two different weather conditions. The uncertainty was calculated using ISO 17123-5:2012, which is an international standard developed for acquiring measurement uncertainties of total stations, to investigate whether this standard could also be applicable for TLS. The survey, which took place outdoor at the University of Gävle, was carried out by scanning ...

On-road transportation contributes 22% of the total CO2 emissions and more than 44% of oil consumption in the U.S. technological advancements and use of alternative fuels are often suggested as ways to reduce these emissions. However, many parameters and relationships that determine the future characteristics of the light-duty vehicle (LDV) fleet and how they change over time are inherently uncertain. Policy makers need to make decisions today given these uncertainties, to shape the future of light-duty vehicles. Decision makers thus need to know the impact of uncertainties on the outcome of their decisions and the associated risks. This paper explores a carefully constructed detailed pathway that results in a significant reduction in fuel use and greenhouse gases (GHG) emissions in 2050. Inputs are assigned realistic uncertainty bounds, and the impact of uncertainty on this pathway is analyzed. A novel probabilistic fleet model is used here to quantify the uncertainties within advanced vehicle ...

Bilinguals have distinct linguistic experiences relative to monolinguals, stemming from interactions with the environment and the individuals therein. Theories of language control hypothesize that these experiences play a role in adapting the neurocognitive systems responsible for control. Here we posit a potential mechanism for these adaptations, namely that bilinguals face additional language-related uncertainties on top of other ambiguities that regularly occur in language, such as lexical and syntactic competition. When faced with uncertainty in the environment, people adapt internal representations to lessen these uncertainties, which can aid in executive control and decision-making.. We overview a cognitive framework on uncertainty, which we extend to language and bilingualism. We then review two case studies, assessing language-related uncertainty for bilingual contexts using language entropy and network scientific approaches. Overall, we find that there is substantial individual ...

TY - JOUR. T1 - A novel approach to parameter uncertainty analysis of hydrological models using neural networks. AU - Shrestha, DL. AU - Kayastha, N. AU - Solomatine, DP. N1 - neotk. PY - 2009. Y1 - 2009. KW - Peer-lijst tijdschrift. UR - http://www.hydrol-earth-syst-sci-discuss.net/6/1677/2009. M3 - Article. VL - 6. SP - 1677. EP - 1706. JO - Hydrology and Earth System Sciences Discussions. JF - Hydrology and Earth System Sciences Discussions. SN - 1812-2116. ER - ...

TY - JOUR. T1 - A new didactic approach to statistical analysis of measurement data for the evaluation of measurement uncertainty - SAM-EMU. AU - Płowucha, W.. AU - Werner, T.. AU - Savio, E.. AU - Blunt, L.. AU - Jakubiec, W.. PY - 2012/12. Y1 - 2012/12. N2 - This paper describes assumptions, aims, methodology, content and consortium make up of a European project (SAM-EMU) founded under the Erasmus Lifelong Learning Programme. The project has developed learning materials in the field of evaluation of measurement uncertainty. It is available in the form of a multimedia web based course, which has many advantages. This format is commonly accepted as a good way to prepare an EU wide vocational training vehicle. The course is available in English.. AB - This paper describes assumptions, aims, methodology, content and consortium make up of a European project (SAM-EMU) founded under the Erasmus Lifelong Learning Programme. The project has developed learning materials in the field of evaluation of ...

Measurement Uncertainty Budget and ISO/IEC 17025 Accreditation Consulting for testing & calibration labs. FREE measurement uncertainty guide

A comprehensive framework for predicting response to therapy on the basis of heterogeneity in dceMRI parameter maps is presented. A motion-correction method for dceMRI sequences is extended to incorporate uncertainties in the pharmacokinetic parameter maps using a variational Bayes framework. Simple measures of heterogeneity (with and without uncertainty) in parameter maps for colorectal cancer tumours imaged before therapy are computed, and tested for their ability to distinguish between responders and non-responders to therapy. The statistical analysis demonstrates the importance of using the spatial distribution of parameters, and their uncertainties, when computing heterogeneity measures and using them to predict response on the basis of the pre-therapy scan. The results also demonstrate the benefits of using the ratio of Ktrans with the bolus arrival time as a biomarker.

This course provides software training to help geoscientists better understand the geological uncertainties in their 1D, 2D, or 3D petroleum system models. You will learn how to use PetroRisk, the uncertainty modeling tool within the PetroMod Basin & Petroleum Systems Modeling software package. PetroRisk assesses geological uncertainty and follows the entire migration path to provide probabilistic estimates for accumulations.. This course teaches you how to use the PetroMod* PetroRisk module to understand and quantify the uncertainties in your petroleum systems models. The course combines lectures on statistics and uncertainty analysis with practical exercises designed to show the impact of uncertainties in model input data. You will learn about dependencies and correlations between geological processes and model uncertainties.. This workshop is an elective component in the PetroMod Education Services offering. Students successfully completing this course will be able evaluate the impact of ...

Background The increasing use of the methods of evidence-based medicine to keep up-to-date with the research literature highlights the absence of high-quality evidence in many areas in psychiatry. Aims To outline current uncertainties in the maintenance treatment of bipolar disorder and to describe some of the decisions involved in designing a large simple trial. Method We describe some of the strategies of evidence-based medicine, and how they can be applied in practice, focusing specifically on the area of bipolar disorder. Results One of the key clinical uncertainties in the treatment of bipolar disorder is the place of maintenance drug treatments and their relative efficacy. A large-scale study, the Bipolar Affective DISORDER: Lithium Anticonvulsant Evaluation (BALANCE) trial, is proposed to compare the effectiveness of lithium, valproate and the combination of lithium and valproate. Conclusions Providing reliable answers to key clinical questions in psychiatry will require new approaches to

In this work, we examined the evolution of PET under future climate conditions. We also investigated to what extent seven different classical PET formulations could modify the partitioning of uncertainty associated with climate projections.

xml version=1.0?,,rfc1807,,datestamp,2018-09-04T10:32:56.5948680,/datestamp,,bib-version,v2,/bib-version,,id,40560,/id,,entry,2018-06-04,/entry,,title,Fuzzy uncertainty analysis in the flutter boundary of an aircraft wing subjected to a thrust force,/title,,swanseaauthors,,author,,sid,f207b17edda9c4c3ea074cbb7555efc1,/sid,,ORCID,0000-0002-3721-4980,/ORCID,,firstname,Hamed,/firstname,,surname,Haddad Khodaparast,/surname,,name,Hamed Haddad Khodaparast,/name,,active,true,/active,,ethesisStudent,false,/ethesisStudent,,/author,,/swanseaauthors,,date,2018-06-04,/date,,deptcode,AERO,/deptcode,,abstract,In this study, flutter uncertainty analysis of an aircraft wing subjected to a thrust force is investigated using fuzzy method. The linear wing model contains bending and torsional flexibility and the engine is considered as a rigid external mass with thrust force. Peters’ unsteady thin airfoil theory is used to model the aerodynamic loading. The aeroelastic governing equations are derived based ...

NEW YORK Small business owners may be experiencing sticker shock now that insurers are revealing the rates they want to charge under the new health care law.

To conclusively determine whether aldosterone antagonists confer additional benefit on reducing SCDs in patients with ICDs, one would need to design a study in which patients with ICDs (and preferably a group without ICDs as well) were randomized to aldosterone antagonists versus placebo in addition to the usual heart failure medicines. Unfortunately, and to the best of our knowledge, such a study has not been performed. We have been able to obtain some observational retrospective data from MADIT II and the COMPANION trial that address this issue to some extent. We briefly present our findings, realizing that limitations exist that must be kept in mind when these data are viewed. The limitations of this analysis include the following: a lack of randomization for the use of spironolactone; a relatively small number of patients who were assigned to spironolactone, which resulted in the studies not being powered to definitely answer the question about a benefit of aldosterone antagonists in ...

There is a lack of evidence that medicines for osteoarthritis are effective in the long term, according to a review in the Journal of the American Medical Association.

Although 6% may not seem like much to the casual observer, 5.7 Mb/d represents the largest oil supply disruption ever, surpassing the combined loss of Kuwaiti and Iraqi production following the latters invasion of the former in August 1990 that drove a doubling of oil prices, seeing the US plun...

Abstract. This paper describes an approach to derive probabilistic predictions of local winter storm damage occurrences from a global medium-range ensemble prediction system (EPS). Predictions of storm damage occurrences are subject to large uncertainty due to meteorological forecast uncertainty (typically addressed by means of ensemble predictions) and uncertainties in modelling weather impacts. The latter uncertainty arises from the fact that local vulnerabilities are not known in sufficient detail to allow for a deterministic prediction of damages, even if the forecasted gust wind speed contains no uncertainty. Thus, to estimate the damage model uncertainty, a statistical model based on logistic regression analysis is employed, relating meteorological analyses to historical damage records. A quantification of the two individual contributions (meteorological and damage model uncertainty) to the total forecast uncertainty is achieved by neglecting individual uncertainty sources and analysing ...

This paper explores ways to integrate model uncertainty into policy evaluation. We first describe a general framework for the incorporation of model uncertainty into standard econometric calculations. This framework employs Bayesian model averaging methods that have begun to appear in a range of economic studies. Second, we illustrate these general ideas in the context of assessment of simple monetary policy rules for some standard New Keynesian specifications. The specifications vary in their treatment of expectations as well as in the dynamics of output and inflation. We conclude that the Taylor rule has good robustness properties, but may reasonably be challenged in overall quality with respect to stabilization by alternative simple rules that also condition on lagged interest rates, even though these rules employ parameters that are set without accounting for model uncertainty. ...

Uncertainty quantification (UQ) is the science of quantitative characterization and reduction of uncertainties in both computational and real world applications. It tries to determine how likely certain outcomes are if some aspects of the system are not exactly known. An example would be to predict the acceleration of a human body in a head-on crash with another car: even if we exactly knew the speed, small differences in the manufacturing of individual cars, how tightly every bolt has been tightened, etc., will lead to different results that can only be predicted in a statistical sense. Many problems in the natural sciences and engineering are also rife with sources of uncertainty. Computer experiments on computer simulations are the most common approach to study problems in uncertainty quantification. Uncertainty can enter mathematical models and experimental measurements in various contexts. One way to categorize the sources of uncertainty is to consider: Parameter uncertainty This comes from ...

Description: The purpose of this dissertation is to develop a theory that helps explain the conditions under which firms select certain project evaluation techniques. This study uses contingency theory to analyze the impact of environmental uncertainty on the choice of project evaluation techniques. In addition to a direct measure of uncertainty, several dimensions of uncertainty are included in this study. These dimensions of uncertainty include control structure, method of financing, foreign assets, method of growth, and product domination. This study also analyzes the use of project evaluation, management science and risk management techniques in US firms over time and in UK firms over time in order to compare to prior research. A comparison of firms in the two countries are also provided. The primary method of data collection was a survey instrument. Data were also collected from annual reports and various other public sources. The variables that appear significant in the choice of project ...

Description: The purpose of this dissertation is to develop a theory that helps explain the conditions under which firms select certain project evaluation techniques. This study uses contingency theory to analyze the impact of environmental uncertainty on the choice of project evaluation techniques. In addition to a direct measure of uncertainty, several dimensions of uncertainty are included in this study. These dimensions of uncertainty include control structure, method of financing, foreign assets, method of growth, and product domination. This study also analyzes the use of project evaluation, management science and risk management techniques in US firms over time and in UK firms over time in order to compare to prior research. A comparison of firms in the two countries are also provided. The primary method of data collection was a survey instrument. Data were also collected from annual reports and various other public sources. The variables that appear significant in the choice of project ...

Ive been looking at it from a different perspective. From the fitted equation for y, we can calculate dy/dt. The question is, what is the uncertainty on this calculated velocity dy/dt? According to the OP, the root mean square error on y (interpreted by me to be the uncertainty on y) is u_y. My focus was on getting an estimate of the rms error on the velocity dy/dt, which Im interpreting as the uncertainty on dy/dt. My method of doing this is by estimating the local deviation between the fitted velocity, and the velocity that would be obtained by differentiating the displacement data with respect to time. Assuming that the deviations in the displacements at the various times are uncorrelated with each other, I came up with the result that u_v=√2u_y/Δt ...

Managing Uncertainties in Interactive Systems: 10.4018/978-1-59904-849-9.ch153: To adapt users input and tasks an interactive system must be able to establish a set of assumptions about users profiles and task characteristics, which is

In this episode of the Managing Uncertainty Podcast, the experts at Bryghtpath discuss Physical Security Penetration Testing, aka Red Teaming

Certain feedingstuffs are sources of contamination for animals with cadmium (Cd) and lead (Pb). Different approaches for sample digestion, performance assessment, and measurement uncertainty for the...

This book presents worked examples of five analytical procedures. These practical examples address traceability, validation and measurement uncertainty aspects in a systematic and consistent way, and cover applications in the analysis of water, food, as well as ores and minerals. This concept is bas.... More. ...

Natural night ventilation is an energy efficient way to improve thermal summer comfort. Coupled thermal and ventilation simulation tools predict the performances. Nevertheless, the reliability of the simulation results with regard to the assumptions in the input, is still unclear. Uncertainty analysis is chosen to determine the uncertainty on the predicted performances of

Told in three parts, the book explores associations between economic growth, policy uncertainty and the key domestic and international transmission channels, and transmission effects, of global financial regulatory and domestic macro-economic uncertainties on subdued and volatile economic recovery, financial channels, lending rate margins, and credit growth. This short report describes the PASTRES (Pastoralism, Uncertainty and Resilience: Global Lessons from the Margins) project, its objectives and early implementation. Resources. The global economic conditions remain fragile and it is difficult to predict customer demand and raw material costs. With new sources of uncertainty seemingly proliferating by the day, a broad economic slowdown should come as no surprise. And as long as the rules and institutions governing the global economy remain in doubt, continued underperformance is to be expected. The World Economic Situation and Prospects Monthly Briefing is prepared by the Global Economic ...

The problem of non-contact surface defect area measurement at complex-shape objects under videoendoscopic control is considered. Major factors contributing to the measurement uncertainty are analyzed for the first time. The proposed method of accuracy analysis is based on the evaluation of 3D coordinates of surface points from 2D projections under assumption of projective camera model and Mahalanobis distance minimization in the image plane. Expressions for area measurement error caused by sum-of-triangles approximation are obtained analytically for practically important cases of cylindrical and spherical surfaces. It is shown that the magnitude of this error component for a single triangle does not exceed 1% for the real values of parameters of the endoscopic imaging system. Expressions are derived for area measurement uncertainty evaluation on arbitrary shape surfaces, caused by measurement errors of 3D coordinates of individual points with and without a priori information about surface shape.

This recommended practice defines a common viewpoint of the evaluation of uncertainty in calibration and its application in testing procedures for Instrument Transformers (ITs). Definition of how to take into account the sources of uncertainty of the measurement system and how to combine their effects in order to evaluate the uncertainty on the measurement results. The recommended practice also presents the common requirements to be used during tests for assessing the accuracy of ITs.

Downloadable! In this paper stochastic dynamic programming is used to investigate land conversion decisions taken by a multitude of landholders under uncertainty about the value of environmental services and irreversible development. We study land conversion under competition on the market for agricultural products when voluntary and mandatory measures are combined by the Government to induce adequate participation in a conservation plan. We study the impact of uncertainty on the optimal conversion policy and discuss conversion dynamics under different policy scenarios on the basis of the relative long-run expected rate of deforestation. Interestingly, we show that uncertainty, even if it induces conversion postponement in the short-run, increases the average rate of deforestation and reduces expected time for total conversion in the long run. Finally, we illustrate our findings through some numerical simulations.

Squeezing what hasnt been squeezed before. Most people attempt to reduce the little uncertainties of life by carrying umbrellas on cloudy days, purchasing automobile insurance or hiring inspectors to evaluate homes they might consider purchasing. For scientists, reducing uncertainty is a no less important goal, though in the weird realm of quantum physics, the term has a more specific meaning.. For scientists working in quantum physics, the Heisenberg Uncertainty Principle says that measurements of properties such as the momentum of an object and its exact position cannot be simultaneously specified with arbitrary accuracy. As a result, there must be some uncertainty in either the exact position of the object, or its exact momentum. The amount of uncertainty can be determined, and is often represented graphically by a circle showing the area within which the measurement actually lies.. Over the past few decades, scientists have learned to cheat a bit on the Uncertainty Principle through a ...

Decision Support Tools & Uncertainty Analysis Services by E Risk Sciences, LLP. Making environmental and public policy decisions involves identifying, ...

Simulations and pre-experiment uncertainty analyses for a hydrogen diffusion experiment using a two side purged membrane ...

TY - JOUR. T1 - Uncertainty analysis for the determination of permeability and specific storage from the pulse-transient technique. AU - Song, Insun. AU - Rathbun, Andrew P.. AU - Saffer, Demian M.. N1 - Funding Information: This work was supported by the Basic Research Program of KIGAM , and by NSF grant EAR-0746192 . We are thankful to Stefan Finsterle at LBNL for his pre-review of this paper, and to two anonymous IJRMMS reviewers for their comments and suggestions.. PY - 2013/12. Y1 - 2013/12. UR - http://www.scopus.com/inward/record.url?scp=84884344208&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=84884344208&partnerID=8YFLogxK. U2 - 10.1016/j.ijrmms.2013.08.032. DO - 10.1016/j.ijrmms.2013.08.032. M3 - Article. AN - SCOPUS:84884344208. VL - 64. SP - 105. EP - 111. JO - International Journal of Rock Mechanics and Mining Sciences. JF - International Journal of Rock Mechanics and Mining Sciences. SN - 1365-1609. ER - ...

Aerosols and their effect on the radiative properties of clouds are one of the largest sources of uncertainty in calculations of the Earths energy budget. Here the sensitivity of aerosol-cloud albedo effect forcing to 31 aerosol parameters is quantified. Sensitivities are compared over three periods; 1850-2008, 1978-2008, and 1998-2008. Despite declining global anthropogenic SO2 emissions during 1978-2008, a cancelation of regional positive and negative forcings leads to a near-zero global mean cloud albedo effect forcing. In contrast to existing negative estimates, our results suggest that the aerosol-cloud albedo effect was likely positive (0.006 to 0.028Wm-2) in the recent decade, making it harder to explain the temperature hiatus as a forced response. Proportional contributions to forcing variance from aerosol processes and natural and anthropogenic emissions are found to be period dependent. To better constrain forcing estimates, the processes that dominate uncertainty on the timescale of ...

How do changes in employment uncertainty matter for fertility? Empirical studies on the impact of employment uncertainty on reproductive decision-making offer a variety of conclusions, ranging from ge

Biomechanical dynamics simulations facilitate the investigation of fundamental principles and concepts in human motions. The simulation results help to explain experimentally observed phenomena and reveal underlying mechanisms. Due to unavoidable restrictions in biomechanical measurements and the determination of personalized model parameters, the simulation results always lie within a specific range of possible solutions. Since these uncertainties can have a significant influence on derived scientific conclusions and clinical decisions, this thesis provides a systematic uncertainty and sensitivity analysis of the common inverse dynamics simulation to assess uncertainty propagation and the contribution of individual uncertainty sources in the estimation of joint torques resulting from particular human motions. The analysis evaluates uncertainties and sensitivities in selected joint torque estimates of the lower limbs for three motion tasks performed by a female and male subject. It follows the ...

During a nuclear plant accident, five accident events are usually considered, including core uncovery, core outlet temperature arrived at 650 °C, core support plate failure, reactor vessel failure and containment failure. In accident emergency aspect, when an accident happens, the initial event can be utilized in the severe accident management system which is based on MAAP to simulate the long process of the accident, so as to provide support for operators to take actions. However, in MAAP, many sensitivity parameters exist, which reflect phenomenological uncertainty or models uncertainty and will influence the happening time of the five accident events above. In this paper, based on MAAP5 and LOCAs, the CPR1000 is simulated to analyze the influences of MAAP5s sensitivity parameters reflecting phenomenological uncertainty on the accident process, which is aimed to find out the sensitivity parameters associated to the five important accident events and build the database between these ...

Decisions involving uncertainty and risk are standard occurrences in water resource management. Demand/sales models need information about future population, economic cycles, rates, passive conservation, and weather, all of which can be uncertain. Decisions about the timing and size of capital investments, built on inaccurate estimates of future levels of demand and supply, can therefore be flawed. Similarly, uncertainty about future sales confounds financial planning. Because information about uncertainty and risk is seldom expressed in concrete terms, ambiguity abounds. Meanwhile, the effect of uncertainty on decisions tends to be downplayed. Accordingly, an adequate accounting for uncertainty and risk requires not only new analytic approaches, but advances in both the way analysts communicate with policy makers and in the way policy makers communicate with each other. This project presents the principles and methods of the new discipline of probability management to address these issues, providing a

TY - JOUR. T1 - H-infinity vehicle control using nondimensional perturbation measures. AU - Brennan, S.. AU - Alleyne, A.. PY - 2002. Y1 - 2002. N2 - Robust controller design techniques have been applied to the field of vehicle control to achieve many different performance measures: robust yaw rate control [1], robust lateral positioning using one [2, 3] or more [4-6] driver inputs, robust observer design, and so on. A difficulty with many published approaches is to obtain an adequate description of the model uncertainty. Most bounds on plant frequency responses or parameter perturbations are based on ad-hoc limits that rely primarily on the designers personal choice. The resulting controller design is therefore often vehicle specific, and is suitable only for application to a single design vehicle. This work shows that (a) the description of model uncertainty is not a design variable, (b) meaningful bounds on model uncertainty can be obtained from data and should be sought, and (c) these ...

Aim of the study. The aim of the study was to assess the degree of illness uncertainty and to determine the correlates of uncertainty, as well as to analyse relationships between uncertainty and quality of life of patients with multiple sclerosis. Materials and methods. The study sample consisted of 40 patients with MS diagnosis, including 29 women and 11 men aged 23 65 years. Uncertainty was assessed using the Polish version of the Mishel Unc ertainty in Illness Scale (MUIS), quality of life with the help of MSQOL 54 questionnaire, anxiety and depression with the HADS scale, and the neurological status with the EDSS scale ...

Uncertainty often affects molecular biology experiments and data for different reasons. Heterogeneity of gene or protein expression within the same tumor tissue is an example of biological uncertainty which should be taken into account when molecular markers are used in decision making. Tissue Microarray (TMA) experiments allow for large scale profiling of tissue biopsies, investigating protein patterns characterizing specific disease states. TMA studies deal with multiple sampling of the same patient, and therefore with multiple measurements of same protein target, to account for possible biological heterogeneity. The aim of this paper is to provide and validate a classification model taking into consideration the uncertainty associated with measuring replicate samples. We propose an extension of the well-known Naïve Bayes classifier, which accounts for biological heterogeneity in a probabilistic framework, relying on Bayesian hierarchical models. The model, which can be efficiently learned from the

TY - JOUR. T1 - SU‐F‐BRA‐12. T2 - Comprehensive Uncertainty Analysis of Proton Stopping‐Power‐Ratio Estimation Using a KV‐MV Dual Energy CT Scanner (DECT) for Margin Reduction. AU - Yang, M.. AU - Zhu, X.. AU - Clayton, J.. AU - Virshup, G.. AU - Mohan, R.. AU - Dong, L.. PY - 2011. Y1 - 2011. N2 - Purpose: To analyze the uncertainties in proton stopping‐power‐ratios (SPRs) calculation using a kV‐MV DECT and evaluate the potential for margin reduction for proton therapyMethods: Sources of uncertainties in SPR estimation were broken into five categories: CT imaging uncertainties, CT modeling error, uncertainties in the mean‐excitation‐energy, SPR variation with proton energy and uncertainties due to variations in human tissue compositions. Additionally, lung, soft and bone tissues were analyzed separately because their uncertainties are too different to be considered as the same tissue type. The uncertainty of 1‐standard‐deviation (1‐SD) was determined for each ...

This paper presents a methodology to represent and propagate epistemic uncertainties within a scenario-based earthquake risk model. Unlike randomness, epistemic uncertainty stems from incomplete, vague or imprecise information. This source of uncertainties still requires the development of adequate tools in seismic risk analysis. We propose to use the possibility theory to represent three types of epistemic uncertainties, namely imprecision, model uncertainty and vagueness due to qualitative information. For illustration, an earthquake risk assessment for the city of Lourdes (Southern France) using this approach is presented. Once adequately represented, uncertainties are propagated and they result in a family of probabilistic damage curves. The latter is synthesized, using the concept of fuzzy random variables, by means of indicators bounding the true probability to exceed a given damage grade. The gap between the pair of probabilistic indicators reflects the imprecise character of uncertainty related

In intelligent tutoring systems, student or user modeling implies dealing with imperfect and uncertain knowledge. One of the artificial intelligence techniques used for uncertainty management is that of Bayesian networks. This paradigm is recommended in the situation when exist dependencies between data and qualitative information about these data. In this work we present a student knowledge diagnosis model based on representation with Bayesian networks. The educational system incorporate a multimedia interface for accomplishes the testing tools. The results of testing sessions are represented and interpreted with probability theory in order to ensure an adapted support for the student. The aims of the computer assisted application that contains this diagnose module are to support the student in personalized learning process and errors explanation.

As a very fundamental principle in quantum physics, uncertainty principle has been studied intensively via various uncertainty inequalities. A natural and fundamental question is whether an equality exists for the uncertainty principle. Here we derive an entropic uncertainty equality relation for a bipartite system consisting of a quantum system and a coupled quantum memory, based on the information measure introduced by Brukner and Zeilinger (Phys. Rev. Lett. 83:3354, 1999). The equality indicates that the sum of measurement uncertainties over a complete set of mutually unbiased bases on a subsystem is equal to a total, fixed uncertainty determined by the initial bipartite state. For the special case where the system and the memory are the maximally entangled, all of the uncertainties related to each mutually unbiased base measurement are zero, which is substantially different from the uncertainty inequality relation. The results are meaningful for fundamental reasons and give rise to operational

Experiments with relatively high doses are often used to predict risks at appreciably lower doses. A point of departure (PoD) can be calculated as the dose associated with a specified moderate response level that is often in the range of experimental doses considered. A linear extrapolation to lower doses often follows. An alternative to the PoD method is to develop a model that accounts for the model uncertainty in the dose-response relationship and to use this model to estimate the risk at low doses. Two such approaches that account for model uncertainty are model averaging (MA) and semi-parametric methods. We use these methods, along with the PoD approach in the context of a large animal (40,000+ animal) bioassay that exhibited sub-linearity. When models are fit to high dose data and risks at low doses are predicted, the methods that account for model uncertainty produce dose estimates associated with an excess risk that are closer to the observed risk than the PoD linearization. This ...

The current paper presents a comparative investigation of the experimental as well as simulated evaluation of effective area and the associated uncertainties, of a pneumatic pressure reference standard (NPLI-4) of CSIR-National Physical Laboratory, India, (NPLI). The experimental evaluation has been compared to the simulated estimation of the effective area obtained through Monte Carlo method (MCM). The Monte Carlo method has been applied by taking fixed number of trials (FMCM) and also by trials chosen adaptively (AMCM). The measurement uncertainties have been calculated using the conventional method, i.e., law of propagation of uncertainty (LPU) as well as MCM. Experimentally, the NPLI-4 has cross-floated against our newly established pneumatic primary pressure standard (NPLI-P10), which is a large diameter piston gauge. An excellent agreement in effective area and measurement uncertainty has been observed between these approaches ...

TY - JOUR. T1 - Identification and uncertainty estimation of vertical reflectivity profiles using a Lagrangian approach to support quantitative precipitation measurements by weather radar. AU - Hazenberg, P.. AU - Torfs, P. J.J.F.. AU - Leijnse, H.. AU - Delrieu, G.. AU - Uijlenhoet, R.. PY - 2013/9/27. Y1 - 2013/9/27. N2 - This paper presents a novel approach to estimate the vertical profile of reflectivity (VPR) from volumetric weather radar data using both a traditional Eulerian as well as a newly proposed Lagrangian implementation. For this latter implementation, the recently developed Rotational Carpenter Square Cluster Algorithm (RoCaSCA) is used to delineate precipitation regions at different reflectivity levels. A piecewise linear VPR is estimated for either stratiform or neither stratiform/convective precipitation. As a second aspect of this paper, a novel approach is presented which is able to account for the impact of VPR uncertainty on the estimated radar rainfall variability. ...

Large uncertainties may exist in modeling various processes determining fisheries population dynamics. The uncertainties may come from various sources such as environmental variations (process errors), measurement errors, and model errors. In order to quantify the uncertainties, an understanding of the complex model error structure in the population dynamic models and how the model error structure affects the parameter estimation is important. In this study I evaluated and quantified the uncertainties in modeling various processes of fisheries population dynamics using Monte Carlo simulations and applied the proposed methods to Atlantic cod stocks. -- The generalized linear model approach, which can readily deal with different error structures, were used to identify suitable model error structure in stock-recruitment modeling, stock biomass modeling, and age-structure population modeling. A simulation study was developed to evaluate the influence of stock mixing on the collection of fish growth ...

This paper deals with the robust performance problem of a linear time-invariant control system in the presence of robust controller uncertainty. Assuming that plant uncertainty is modeled as an additive perturbation, a geometrical approach is followed in order to find a necessary and sufficient condition for robust performance in the form of a bound on the magnitude of controller uncertainty. This frequency domain bound is derived by converting the problem into an optimization problem, whose solution is shown to be more time-efficient than a conventional structured singular value calculation. The bound on controller uncertainty can be used in controller order reduction and implementation problems.

Hashimoto, Shintaro; Sato, Tatsuhiko. Particle transport simulations based on the Monte Carlo method have been applied to shielding calculations. Estimation of not only statistical uncertainty related to the number of trials but also systematic one induced by unclear physical quantities is required to confirm the reliability of calculated results. In this study, we applied a method based on analysis of variance to shielding calculations. We proposed random- and three-condition methods. The first one determines randomly the value of the unclear quantity, while the second one uses only three values: the default value, upper and lower limits. The systematic uncertainty can be estimated adequately by the random-condition method, though it needs the large computational cost. The three-condition method can provide almost the same estimate as the random-condition method when the effect of the variation is monotonic. We found criterion to confirm convergence of the systematic uncertainty as the number ...

Managing an invasive species is particularly challenging as little is generally known about the species biological characteristics in its new habitat. In practice, removal of individuals often starts before the species is studied to provide the information that will later improve control. Therefore, the locations and the amount of control have to be determined in the face of great uncertainty about the species characteristics and with a limited amount of resources. We propose framing spatial control as a linear programming optimization problem. This formulation, paired with a discrete reaction-diffusion model, permits calculation of an optimal control strategy that minimizes the remaining number of invaders for a fixed cost or that minimizes the control cost for containment or protecting specific areas from invasion. We propose computing the optimal strategy for a range of possible model parameters, representing current uncertainty on the possible invasion scenarios. Then, a best strategy can be

The Indian Ocean Tuna Commission (IOTC),. RECOGNISING the authority and responsibility of IOTC to manage bigeye tuna in the IOTC area of competence (Convention Area), at the international level;. RECOGNISING ALSO the nature of the international market for bigeye tuna in the Convention Area;. RECOGNISING ALSO that there is uncertainty on the catch of bigeye tuna in the Convention Area and that the availability of trade data would greatly assist in reducing such uncertainty;. RECOGNISING ALSO that bigeye tuna is the main target species of flag of convenience fishing operations and that most of the bigeye tuna harvested by such fishing vessels are exported to Contracting Parties, especially to Japan;. RECALLING that the International Commission for the Conservation of Atlantic Tunas (ICCAT) has established its Bluefin Tuna, Bigeye Tuna and Swordfish Statistical Document Programs, and that the Commission for the Conservation of Southern Bluefin Tuna (CCSBT) has also established its Southern ...

Archaeozoological and genetic data indicate that taurine cattle were first domesticated from local wild ox (aurochs) in the Near East some 10,500 years ago. However, while modern mitochondrial DNA variation indicates early Holocene founding event(s), a lack of ancient DNA data from the region of origin, variation in mutation rate estimates and limited application of appropriate inference methodologies have resulted in uncertainty on the number of animals first domesticated. A large number would be expected if cattle domestication was a technologically straightforward and unexacting region-wide phenomenon, while a smaller number would be consistent with a more complex and challenging process. We report mitochondrial DNA sequences from 15 Neolithic to Iron Age Iranian domestic cattle and, in conjunction with modern data, use serial coalescent simulation and approximate Bayesian computation to estimate that around 80 female aurochs were initially domesticated. Such a low number is consistent with ...

Introduction. A key issue in understanding the nitrogen (N) cycle is to determine human-induced perturbations to the natural N cycle. Such determination involves first understanding, describing, and quantifying the natural N cycle at global, regional, and local scales. The concentration of N species in the environment varies greatly over short distances. This natural variability can make it difficult to evaluate human influences on the N cycle. Ideally, all the components of the natural N cycle should be measured with known precision and accuracy. In practice, this is impossible. In reality, estimates are made of the magnitude of the major components of the N cycle based on fragmentary measurements. There are large uncertainties on the magnitude of the estimated natural fluxes of N and the natural storage of N in the N reservoirs. For example, the estimates of marine N fixation range from 40-200 million metric tons/yr, atmospheric deposition of organic-N 10-100 million metric tons/yr and, ...

There is often uncertainty on how validation and verification of newly introduced tests should be conducted, and there is a real risk of verification becoming a meaningless ritual, rather than a useful exercise. This article reviews the literature and makes recommendations regarding the validation and verification of automated urine particles analysers. A generic practical approach to verification is also recommended. For many analysers, the accuracy of white blood cells, epithelial cells and bacterial counts is corroborated by a number of independent evaluations; thus, any verification laboratory work could be significantly scaled down. Conversely, in the scenario that automated urine microscopy is used as a screening test to reduce the number of urines cultured, the extremely variable performance reported in the literature requires a full-scale verification to define the optimal cut-off values that give a sensitivity of ,98% with the local settings and circumstances. With some analysers, the ...

Although coronary-artery bypass grafting (CABG) is the standard choice of revascularization for significant left main coronary artery (LMCA) disease, percutaneous coronary intervention (PCI) for LMCA disease has been widely expanded with adoption of drug-eluting stents (DES). Several small- and moderate-sized trials of CABG and first-generation DES showed that PCI might be a good alternative for selected patients with LMCA disease. However, these early trials were relatively underpowered and comparative results of contemporary DES and CABG were clearly required. Subsequently, two large-sized trials comparing CABG and contemporary DES (EXCEL and NOBLE) were conducted, but these trials showed conflicting results with regards to the effects of PCI and CABG on clinical outcomes, which raises further uncertainty on the optimal revascularization for LMCA disease. This article serves to summarize the key findings of landmark clinical trials, to share our knowledge and experience and to express personal

The optimization of the coated metallic nanoparticles and nanoshells is a current challenge for biological applications, especially for cancer photothermal therapy, considering both the continuous improvement of their fabrication and the increasing requirement of efficiency. The efficiency of the coupling between illumination with such nanostructures for burning purposes depends unevenly on their geometrical parameters (radius, thickness of the shell) and material parameters (permittivities which depend on the illumination wavelength). Through a Monte-Carlo method, we propose a numerical study of such nanodevice, to evaluate tolerances (or uncertainty) on these parameters, given a threshold of efficiency, to facilitate the design of nanoparticles. The results could help to focus on the relevant parameters of the engineering process for which the absorbed energy is the most dependant. The Monte-Carlo method confirms that the best burning efficiency are obtained for hollow nanospheres and exhibit ...

Downloadable! Herd behavior is often viewed as a signi cant threat for the stability and eciency of nancial markets. This paper sheds new light on the relevance of herd behavior for observed correlation of trades. We introduce numerical simulations of a herd model to derive theory-guided predictions regarding the impact of various aspects of uncertainty on herding intensity. We test the predictions using a novel data set including all real-time transactions of institutional investors in the German stock market. In light of the model simulations, empirical results strongly suggest that the observed correlation of trades is mainly due to the common reaction of investors to new public information and should not be misinterpreted as herd behavior.

Increasing attention has been paid food as a cause of IBS. Food ingestion precipitates or exacerbates symptoms, such as abdominal pain and bloating in patients with IBS through different hypothesised mechanisms including immune and mast cell activation, mechanoreceptor stimulation and chemosensory activation.. Wheat is one of the most relevant IBS triggers, although which component(s) of this cereal is/are involved remain(s) unknown. Gluten, other wheat proteins, for example, amylase-trypsin inhibitors, and fructans (the latter belonging to fermentable oligo-di-mono-saccharides and polyols (FODMAPs)), have been identified as possible factors for symptom generation/exacerbation.. This uncertainty on the true culprit(s) opened a scenario of semantic definitions favoured by the discordant results of double-blind placebo-controlled trials, which have generated various terms ranging from non-coeliac gluten sensitivity to the broader one of non-coeliac wheat or wheat protein sensitivity or, even, ...

To the Editor:. Chronic cough is a difficult clinical problem, partly because there is an absence of well-validated means to assess cough [1, 2]. We have previously reported that the semi-automated computerised Leicester Cough Monitor detects cough accurately over 6 h and that cough frequency is increased in patients with chronic cough compared to controls [3, 4]. There remains uncertainty on the performance of the system over 24 h and across the range of expected cough frequency in larger populations. We set out to address these questions in healthy adult volunteers and adult volunteers with respiratory disease.. 44 healthy volunteers were recruited from those responding to a poster advertisement. All reported no current respiratory symptoms, were nonsmokers with a ,5 pack-yr past smoking history and had normal spirometric values, methacholine airway responsiveness and induced sputum inflammatory cell counts. 78 patients with respiratory disease were recruited from respiratory clinics. The ...

Context: Many different rehabilitation exercises have been recommended in the literature to target the gluteus medius (GMed) muscle based mainly on single-electrode, surface electromyography (EMG) measures. With the GMed consisting of 3 structurally and functionally independent segments, there is uncertainty on whether these exercises will target the individual segments effectively. Objective: To measure individual GMed segmental activity during 6 common, lower-limb rehabilitation exercises in healthy young adults, and determine if there are significant differences between the exercises for each segment. Method: With fine-wire EMG electrodes inserted into the anterior, middle, and posterior segments of the GMed muscle, 10 healthy young adults performed 6 common, lower-limb rehabilitation exercises. Main Outcome Measures: Recorded EMG activity was normalized, then reported and compared with median activity for each of the GMed segments across the 6 exercises. Results: For the anterior GMed ...

Several Western European countries are planning for a massive offshore renewable energy (i.e. wind and wave energy) development (ORED) along the European Atlantic coast and in the Baltic Sea. Acknowledging the scale of ORED, there is an increasing interest in the opportunities offered by the fishery closures and the addition of artificial hard substrata. This is in tandem with uncertainties on positive and negative effects on benthic assemblages and specific species of this large-scale deployment of artificial reefs.. This thesis focuses on the artificial reef effects of ORED, dealing with benthic assemblages on and in the vicinity of wind- and wave power foundations. Field surveys within offshore wind- and wave farms as well as targeted field experiments were conducted. Results suggest that wind- and wave power foundations can positively affect local abundances and diversity of several species of fish and decapods. Reef profile up to 1 m above the seabed may enhance benthic fish numbers. ...

Sigma-Aldrich Corp.s SIAL first-quarter earnings rose 4.3% as the chemical company was helped by improving sales to diagnostic and testing laboratories.. The company, which supplies chemical products and kits for high-technology scientific research, has seen its sales strengthen in recent quarters, helped by acquisitions. Sigma-Aldrich has also been spending to increase growth in China, India and Brazil. However, uncertainty on the economy and research funding in the U.S. and Europe has made some customers cautious about spending.. Chief Executive Rakesh Sachdev said Thursday that overall end markets remain steady with improving pharma trends offset by slower academic spending.. Sigma-Aldrich reported a profit of $122 million, or $1.01 a share, up from $117 million, or 96 cents a share, a year earlier. The latest period included a two-cent negative impact from currency exchange rates. Revenue increased 1.5% to $675 million. Organic sales--which typically include foreign-exchange, acquisition ...

National Grid has taken another step to reduce the coronavirus financial strain and economic uncertainty on upstate New York customers by deferring a bill increase that was scheduled to take effect April 1. The company has asked New York regulators for permission to postpone the previously approved gas and electricity delivery price increases in recognition of the unprecedented hardships the COVID-19 outbreak continues to bring to families across the region.

TY - JOUR. T1 - Elucidation of the mechanism behind the influences of uncertainty avoidance on customer attitudes towards Japanese products and services. AU - Frank, Björn. AU - Torrico, Boris Herbas. AU - Enkawa, Takao. PY - 2013/9/27. Y1 - 2013/9/27. N2 - Sparked by accelerating globalization, many studies have examined the influences of Hofstedes cultural scores on consumer attitudes. Past research suggested that high uncertainty avoidance, a characteristic of Japanese culture, leads to strict customer evaluations and low customer satisfaction. While researchers found clear evidence of this effect for uncertainty avoidance as a facet of country culture, they found mixed evidence for uncertainty avoidance as a personal cultural trait. Based on consumer data from ten industries in Japan, this article thus explores the mechanism linking personal uncertainty avoidance to customer satisfaction and its antecedents (perceived quality, perceived value and firm image). The results suggest that ...

TY - JOUR. T1 - Automatic web service composition based on uncertainty execution effects. AU - Wang, Pengwei. AU - Ding, Zhijun. AU - Jiang, Changjun. AU - Zhou, Mengchu. AU - Zheng, Yuwei. N1 - Publisher Copyright: © 2008-2012 IEEE.. PY - 2016/7/1. Y1 - 2016/7/1. N2 - By arranging multiple existing web services into workflows to create value-added services, automatic web service composition has received much attention in service-oriented computing. A large number of methods have been proposed for it although most of them are merely based on the matching of input-output parameters of services. Besides these parameters, some other elements can affect the execution of services and their composition, such as the preconditions and service execution results. In particular, the execution effects of some services are often uncertain because of the complex and dynamically changing application environments in the real world, and this can cause the emergence of nondeterministic choices in the workflows ...

In this qualitative study of outpatients and their physicians at a public hospital in Sri Lanka, antibiotic prescriptions for ARTIs were common (70%). Interestingly, there was a disassociation between patients expectations for antibiotics and physicians perceptions of patient expectations. Patients generally had a low level of knowledge regarding ARTI etiology and antibiotics, with the main expectation for treatment being the receipt of a medication prescription. Physicians incorrectly perceived that patients desired antibiotics, and also cited factors such as diagnostic uncertainty, competition with the private sector, and lack of time as reasons for possible antibiotic over-prescription. Patients were generally satisfied with treatment received in the OPD, but physicians identified both systematic and patient-based factors that they felt hindered the optimal delivery of care for ARTIs.. Patients desire for antibiotics was the most common reason listed by physicians for possible antibiotic ...

Constrained partitioning of autotrophic and heterotrophic respiration reduces model uncertainties of forest ecosystem carbon fluxes but not stocks Academic Article ...

IBC is a poorly understood disease with a dismal prognosis. Diagnosis is based on variously appreciated clinical signs, and prognostic factors are sorely needed. Despite multimodality treatments, the overall outcome of IBC is almost as grim as that of metastatic breast cancer [25, 26]. Identification of a molecular signature might help to improve the diagnosis, as well as the prognostication and targeted therapy of IBC. The specific molecular alterations underlying IBC are largely unknown, owing to the rarity of the disease together with diagnostic uncertainties and the small size of diagnostic samples, which may have hindered past molecular studies. Moreover, previous molecular studies often grouped IBCs together with non inflammatory LABCs, whereas IBC was recently shown to be distinct from other forms of LABC, probably with different underlying molecular alterations [27, 28].. Two major lines of evidence implicate NF-κB-associated pathways in IBC. First, NF-κB target genes are involved in ...

The use of coronary angiography to investigate patients at risk of coronary artery narrowings has become universal. In most cases, this investigation leads to a successful treatment plan with revascularisation recommended where appropriate. However in a substantial number of patients, the images taken of the coronary arteries can lead to diagnostic uncertainty. Increasingly, doctors are using devices called pressure wires to clarify the significance of coronary artery narrowings in order to tailor patient treatment on an individual basis.. The Radi pressure wire is well recognised as a reliable tool in assessing whether a narrowing is significant in functional terms, that is, does it significantly restrict blood flow to the heart muscle.It consists of a fine wire that is fed into individual major coronary arteries to measure pressure within the vessel itself. In conjunction with the images taken of the arteries, it is very useful in deciding how best to treat patients.. This study enrolls ...

We invite you to discover ThyroidPrint, the most accurate genomic test ever developed for indeterminate thyroid cytology. ThyroidPrint solves the diagnostic uncertainty for patients with Indeterminate thyroid nodules avoiding up to 88% of unnecessary surgeries ...

Recently, time-lapse seismic (4D seismic) has been steadily used to demonstrate the relation between field depletion and 4D seismic response, and, subsequently, to provide more efficient field management. A key component of reservoir monitoring is the knowledge of fluid movement and pressure variation. This information is vital in assisting infill drilling and as a reliable source of data to update reservoir models, and, consequently, in helping to improve model-based reservoir management and decision-making processes. However, in practice, varying levels of uncertainty are inherent in the 4D seismic interpretation of reservoirs that uses a multipart production regime. The complex nature of some 4D seismic signals emphasizes the role of the competing effects of geology, rock and fluid interactions. Hence, a reliable 4D interpretation requires an interdisciplinary approach that entails data analysis and insights from geophysics, engineering and geology. In this study, a stepwise workflow was ...

An introduction to analysis and design of feedback control systems, including classical control theory in the time and frequency domain. Modeling of physical, biological, and information systems using linear and nonlinear differential equations. Linear vs. nonlinear models, and local vs. global behavior, Input/ output response, modeling and model reduction, Stability and perfor¬mance of interconnected systems, including use of block diagrams, Bode plots, the Nyquist criterion, and Lyapunov functions. Robustness and uncertainty management in feedback systems through stochastic and deterministic methods. Basic principles of feedback and its use as a tool for altering the dynamics of systems and managing uncertainty methods. Introductory random processes, Kalman filtering, norms of signals and systems. Topics in 221B: The aim of this course is to introduce the student to the area of nonlinear control systems with a focus on systems analysis and control design. Nonlinear phenomena including ...

The uncertainty is on rise as most of the economy are deciding to become close economy which will affect the global trade. Low crude oil price is going to affect the economies of the major oil supplier (OPEC). The economy was yet to get out of the global financial crisis but this COVID-19 will add more lag in the economy. ...

Background: Young adults with congenital heart disease (CHD) are at risk for chronic illness uncertainty in 4 domains: ambiguity about the state of their illness; lack of information about the disease, its treatment, and comorbidities; complexity of the healthcare system and relationship with healthcare providers; and unpredictability of the illness course and outcome. Chronic uncertainty has been associated with posttraumatic stress symptoms (PTSS) and posttraumatic stress disorder (PTSD). Objective: The aims of this study were to explore how young adults with CHD experience uncertainty and to describe the relationship between PTSS and the appraisal and management process. Methods: An exploratory, mixed methods design was used. Data were collected in person and via Skype from 25 participants (19-35 years old), who were diagnosed with CHD during childhood and able to read and write English. In-depth interviews and the University of California at Los Angeles Posttraumatic Stress Disorder Reaction ...

The majority of existing studies for quantifying uncertainties in climate change impact assessments suggest only the uncertainties of each stage, and not the total uncertainty and its propagation in the whole procedure. Therefore, this study has proposed a new method, the Uncertainty Delta Method (UDM), which can quantify uncertainties using the variances of projections (as the UDM is derived from the first-order Taylor series expansion), to allow for a comprehensive quantification of uncertainty at each stage and also to provide the levels of uncertainty propagation, as follows: total uncertainty, the level of uncertainty increase at each stage, and the percentage of uncertainty at each stage. For quantifying uncertainties at each stage as well as the total uncertainty, all the stages - two emission scenarios (ES), three Global Climate Models (GCMs), two downscaling techniques, and two hydrological models - of the climate change assessment for water resources are conducted. The total ...

In the event of a new infectious disease outbreak, mathematical and simulation models are commonly used to inform policy by evaluating which control strategies will minimize the impact of the epidemic. In the early stages of such outbreaks, substantial parameter uncertainty may limit the ability of models to provide accurate predictions, and policymakers do not have the luxury of waiting for data to alleviate this state of uncertainty. For policymakers, however, it is the selection of the optimal control intervention in the face of uncertainty, rather than accuracy of model predictions, that is the measure of success that counts. We simulate the process of real-time decision-making by fitting an epidemic model to observed, spatially-explicit, infection data at weekly intervals throughout two historical outbreaks of foot-and-mouth disease, UK in 2001 and Miyazaki, Japan in 2010, and compare forward simulations of the impact of switching to an alternative control intervention at the...

A major challenge in modern robotics is to liberate robots from controlled industrial settings, and allow them to interact with humans and changing environments in the real world. The current research attempts to determine if a neurophysiologically motivated model of cortical function in the primate can help to address this challenge. Primates are endowed with cognitive systems that allow them to maximize the feedback from their environment by learning the values of actions in diverse situations and by adjusting their behavioral parameters (i.e. cognitive control) to accommodate unexpected events. In such contexts uncertainty can arise from at least two distinct sources - expected uncertainty resulting from noise during sensory-motor interaction in a known context, and unexpected uncertainty resulting from the changing probabilistic structure of the environment. However, it is not clear how neurophysiological mechanisms of reinforcement learning and cognitive control integrate in the brain to produce

Author Summary Dengue is one of the most important insect-vectored human viral diseases. The principal vector is Aedes aegypti, a mosquito that lives in close association with humans. Currently, there is no effective vaccine available and the only means for limiting dengue outbreaks is vector control. To help design vector control strategies, spatial models of Ae. aegypti population dynamics have been developed. However, the usefulness of such models depends on the reliability of their predictions, which can be affected by different sources of uncertainty including uncertainty in the model parameter estimation, uncertainty in the model structure, measurement errors in the data fed into the model, individual variability, and stochasticity in the environment. This study quantifies uncertainties in the mosquito population dynamics predicted by Skeeter Buster, a spatial model of Ae. aegypti, for the city of Iquitos, Peru. The uncertainty quantification should enable us to better understand the reliability

The uncertainties of life are manifest every day. Some uncertainties are harder than others. My sister has Stage IV lung cancer. But her future is still uncertain, its quite possible the chemo will kill her long before the cancer can. Shes been in the hospital for two weeks now as a mold has developed in her lungs, thanks to chemo bringing her white blood cell count down to zero. On Thursday, I learned she has developed VRE, a anti-biotic resistant bacteria similar but much more rare than MRSA, the OMG of countless House episodes. Of course, because when you are going to ER three times a day for 90 minute infusions of antibiotics, you develop anti-biotic resistant bacteria. I think it is time for her to eat a lot of dessert. Ice cream, apple pie, chocolate cake, brownies and coffee nips. Go for it ...

During the presurgical evaluation of medically intractable epilepsy, isotopic functional imagery provides an increasing amount of data concerning the potential location of the focus. The aim of this study is to facilitate the surgical decision by presenting an image fusion method able to extract epileptogenic foci from periictal single photon emission computed tomography (SPECT), interictal SPECT, fluoro-desoxy-glucose (FDG) position emission tomography (PET), and flumazenil PET. After spatial coregistration, the images are converted into fuzzy maps whose membership functions indicate the pathological degree of each voxel, according to each modality. These maps are then fused together thanks to a combination operator managing uncertainty (due to the sensitivity) and imprecision (due to poor resolution and partial volume effect) of the images. In the framework of possibilistic theory, this operator mimics the way the physicians evaluate and compare the various exams. The technique was s

My research focuses on attempting to better model when and how actions can alter the uncertainty that the agent confronts, subsequently affecting the perception of risk involved in decisions. I am particularly interested in integrating precepts of causal reasoning with (pragmatic) decision support systems and developing a conception of risk based on the control an agent can exercise over the future states of the world. The motivation for my research stems from the fact that current models of decision making do not resonate with the managerial attitude toward uncertainty, which is viewed as something that they believe they control/influence and may decide to voluntarily engage with it. The endeavour of the research is to preserve the primacy of this intuition in the formal construct of models and produce potentially useful research that could help bridge the gap in the understanding between theorists and practitioners. To add or modify information on this page, please contact us at the following ...

TY - GEN. T1 - Improving identifiability in model calibration using multiple responses. AU - Arendt, Paul D.. AU - Chen, Wei. AU - Apley, Daniel. PY - 2011/12/1. Y1 - 2011/12/1. N2 - The use of complex computer simulations to design, improve, optimize, or simply to better understand complex systems in many fields of science and engineering is now ubiquitous. However, simulation models are never a perfect representation of physical reality. Two general sources of uncertainty that account for the differences between simulations and experiments are parameter uncertainty and model uncertainty. The former derives from unknown model parameters, while the latter is caused by underlying missing physics, numerical approximations, and other inaccuracies of the computer simulation that exist even if all of the parameters are known. To obtain knowledge of these two sources of uncertainty, data from computer simulations (usually abundant) and data from physical experiments (typically more limited) are often ...

Perhaps it would help to choose a more mundane example (I really didnt mean for nuclear war or climate change to become the focus - although they are certainly worthy topics to discuss). A company is considering the launch of a new product - many uncertainties are present. Do we believe that evolutionary processes have prepared the decision makers to assess the risks well?. My answer is that evolution is very unlikely to have worked in this way (no, I cant prove that, but my layman understanding of evolution is that it takes too long to have accomplished what is required). Instead, I believe many of the biases that Kahneman and others have investigated are likely to be relevant in a case like this. Gigerenzers claim that decision makers are sophisticated assessors of risks like this seems unwarranted to me. The exception would be if a decision maker had faced many decisions like this in the past - sort of like Gladwells (Blink) examples where emergency responders act using heuristics - honed ...

The proposed study aims to explore the relationships between perceived uncertainty, hope and adaptation in caregivers of children with Down Syndrome (DS). There are often uncertainties surrounding the prognosis of DS which extend into various aspects of the child s life. In addition to the possibility of chronic medical conditions associated with the syndrome, there is also uncertainty related to the level of independence and cognitive, social and behavioral functioning that the child will achieve. It is not fully understood how caregivers adapt to having a child with DS in light of the uncertainty and the particular challenges associated with this condition. While a high level of perceived uncertainty may be seen as a threat to adaptation, there is also evidence that caregivers may find benefits in uncertainty. Literature suggests that a person s level of hope influences how the perceived uncertainty is appraised and that hope is also related to the process of adaptation. There is no research ...

Bayesian inference is an approach to statistics whereby all forms of uncertainty are described in terms of probability. Bayesian inference applies Bayes theorem to observations in order to infer the probability of the truth of an hypothesis. ...

Reducing the sensitivity of IMPT treatment plans to setup errors and range uncertainties via probabilistic treatment planning. Med Phys. 2009 Jan; 36(1):149-63 ...

Confidence intervals tell you about how well you have determined the mean. Assume that the data really are randomly sampled from a Gaussian distribution. If you do this many times, and calculate a confidence interval of the mean from each sample, youd expect about 95 % of those intervals to include the true value of the population mean. The key point is that the confidence interval tells you about the likely location of the true population parameter.. Prediction intervals tell you where you can expect to see the next data point sampled. Assume that the data really are randomly sampled from a Gaussian distribution. Collect a sample of data and calculate a prediction interval. Then sample one more value from the population. If you do this many times, youd expect that next value to lie within that prediction interval in 95% of the samples.The key point is that the prediction interval tells you about the distribution of values, not the uncertainty in determining the population mean. Prediction ...