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Sample records for age conditional probability

  1. Probability in reasoning: a developmental test on conditionals.

    Science.gov (United States)

    Barrouillet, Pierre; Gauffroy, Caroline

    2015-04-01

    Probabilistic theories have been claimed to constitute a new paradigm for the psychology of reasoning. A key assumption of these theories is captured by what they call the Equation, the hypothesis that the meaning of the conditional is probabilistic in nature and that the probability of If p then q is the conditional probability, in such a way that P(if p then q)=P(q|p). Using the probabilistic truth-table task in which participants are required to evaluate the probability of If p then q sentences, the present study explored the pervasiveness of the Equation through ages (from early adolescence to adulthood), types of conditionals (basic, causal, and inducements) and contents. The results reveal that the Equation is a late developmental achievement only endorsed by a narrow majority of educated adults for certain types of conditionals depending on the content they involve. Age-related changes in evaluating the probability of all the conditionals studied closely mirror the development of truth-value judgements observed in previous studies with traditional truth-table tasks. We argue that our modified mental model theory can account for this development, and hence for the findings related with the probability task, which do not consequently support the probabilistic approach of human reasoning over alternative theories. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Irreversibility and conditional probability

    International Nuclear Information System (INIS)

    Stuart, C.I.J.M.

    1989-01-01

    The mathematical entropy - unlike physical entropy - is simply a measure of uniformity for probability distributions in general. So understood, conditional entropies have the same logical structure as conditional probabilities. If, as is sometimes supposed, conditional probabilities are time-reversible, then so are conditional entropies and, paradoxically, both then share this symmetry with physical equations of motion. The paradox is, of course that probabilities yield a direction to time both in statistical mechanics and quantum mechanics, while the equations of motion do not. The supposed time-reversibility of both conditionals seems also to involve a form of retrocausality that is related to, but possibly not the same as, that described by Costa de Beaurgard. The retrocausality is paradoxically at odds with the generally presumed irreversibility of the quantum mechanical measurement process. Further paradox emerges if the supposed time-reversibility of the conditionals is linked with the idea that the thermodynamic entropy is the same thing as 'missing information' since this confounds the thermodynamic and mathematical entropies. However, it is shown that irreversibility is a formal consequence of conditional entropies and, hence, of conditional probabilities also. 8 refs. (Author)

  3. PROBABILITY SURVEYS , CONDITIONAL PROBABILITIES AND ECOLOGICAL RISK ASSESSMENT

    Science.gov (United States)

    We show that probability-based environmental resource monitoring programs, such as the U.S. Environmental Protection Agency's (U.S. EPA) Environmental Monitoring and Assessment Program, and conditional probability analysis can serve as a basis for estimating ecological risk over ...

  4. Conditional Probability Modulates Visual Search Efficiency

    Directory of Open Access Journals (Sweden)

    Bryan eCort

    2013-10-01

    Full Text Available We investigated the effects of probability on visual search. Previous work has shown that people can utilize spatial and sequential probability information to improve target detection. We hypothesized that performance improvements from probability information would extend to the efficiency of visual search. Our task was a simple visual search in which the target was always present among a field of distractors, and could take one of two colors. The absolute probability of the target being either color was 0.5; however, the conditional probability – the likelihood of a particular color given a particular combination of two cues – varied from 0.1 to 0.9. We found that participants searched more efficiently for high conditional probability targets and less efficiently for low conditional probability targets, but only when they were explicitly informed of the probability relationship between cues and target color.

  5. Towards a Categorical Account of Conditional Probability

    Directory of Open Access Journals (Sweden)

    Robert Furber

    2015-11-01

    Full Text Available This paper presents a categorical account of conditional probability, covering both the classical and the quantum case. Classical conditional probabilities are expressed as a certain "triangle-fill-in" condition, connecting marginal and joint probabilities, in the Kleisli category of the distribution monad. The conditional probabilities are induced by a map together with a predicate (the condition. The latter is a predicate in the logic of effect modules on this Kleisli category. This same approach can be transferred to the category of C*-algebras (with positive unital maps, whose predicate logic is also expressed in terms of effect modules. Conditional probabilities can again be expressed via a triangle-fill-in property. In the literature, there are several proposals for what quantum conditional probability should be, and also there are extra difficulties not present in the classical case. At this stage, we only describe quantum systems with classical parametrization.

  6. Students' Understanding of Conditional Probability on Entering University

    Science.gov (United States)

    Reaburn, Robyn

    2013-01-01

    An understanding of conditional probability is essential for students of inferential statistics as it is used in Null Hypothesis Tests. Conditional probability is also used in Bayes' theorem, in the interpretation of medical screening tests and in quality control procedures. This study examines the understanding of conditional probability of…

  7. Secondary School Students' Reasoning about Conditional Probability, Samples, and Sampling Procedures

    Science.gov (United States)

    Prodromou, Theodosia

    2016-01-01

    In the Australian mathematics curriculum, Year 12 students (aged 16-17) are asked to solve conditional probability problems that involve the representation of the problem situation with two-way tables or three-dimensional diagrams and consider sampling procedures that result in different correct answers. In a small exploratory study, we…

  8. The Probability Approach to English If-Conditional Sentences

    Science.gov (United States)

    Wu, Mei

    2012-01-01

    Users of the Probability Approach choose the right one from four basic types of conditional sentences--factual, predictive, hypothetical and counterfactual conditionals, by judging how likely (i.e. the probability) the event in the result-clause will take place when the condition in the if-clause is met. Thirty-three students from the experimental…

  9. An Alternative Version of Conditional Probabilities and Bayes' Rule: An Application of Probability Logic

    Science.gov (United States)

    Satake, Eiki; Amato, Philip P.

    2008-01-01

    This paper presents an alternative version of formulas of conditional probabilities and Bayes' rule that demonstrate how the truth table of elementary mathematical logic applies to the derivations of the conditional probabilities of various complex, compound statements. This new approach is used to calculate the prior and posterior probabilities…

  10. Maximum Entropy and Probability Kinematics Constrained by Conditionals

    Directory of Open Access Journals (Sweden)

    Stefan Lukits

    2015-03-01

    Full Text Available Two open questions of inductive reasoning are solved: (1 does the principle of maximum entropy (PME give a solution to the obverse Majerník problem; and (2 isWagner correct when he claims that Jeffrey’s updating principle (JUP contradicts PME? Majerník shows that PME provides unique and plausible marginal probabilities, given conditional probabilities. The obverse problem posed here is whether PME also provides such conditional probabilities, given certain marginal probabilities. The theorem developed to solve the obverse Majerník problem demonstrates that in the special case introduced by Wagner PME does not contradict JUP, but elegantly generalizes it and offers a more integrated approach to probability updating.

  11. Conditional probabilities in Ponzano-Regge minisuperspace

    International Nuclear Information System (INIS)

    Petryk, Roman; Schleich, Kristin

    2003-01-01

    We examine the Hartle-Hawking no-boundary initial state for the Ponzano-Regge formulation of gravity in three dimensions. We consider the behavior of conditional probabilities and expectation values for geometrical quantities in this initial state for a simple minisuperspace model consisting of a two-parameter set of anisotropic geometries on a 2-sphere boundary. We find dependence on the cutoff used in the construction of Ponzano-Regge amplitudes for expectation values of edge lengths. However, these expectation values are cutoff independent when computed in certain, but not all, conditional probability distributions. Conditions that yield cutoff independent expectation values are those that constrain the boundary geometry to a finite range of edge lengths. We argue that such conditions have a correspondence to fixing a range of local time, as classically associated with the area of a surface for spatially closed cosmologies. Thus these results may hint at how classical spacetime emerges from quantum amplitudes

  12. Retrocausality and conditional probability

    International Nuclear Information System (INIS)

    Stuart, C.I.J.M.

    1989-01-01

    Costa de Beauregard has proposed that physical causality be identified with conditional probability. The proposal is shown to be vulnerable on two accounts. The first, though mathematically trivial, seems to be decisive so far as the current formulation of the proposal is concerned. The second lies in a physical inconsistency which seems to have its source in a Copenhagenlike disavowal of realism in quantum mechanics. 6 refs. (Author)

  13. Conditional probability on MV-algebras

    Czech Academy of Sciences Publication Activity Database

    Kroupa, Tomáš

    2005-01-01

    Roč. 149, č. 2 (2005), s. 369-381 ISSN 0165-0114 R&D Projects: GA AV ČR IAA2075302 Institutional research plan: CEZ:AV0Z10750506 Keywords : conditional probability * tribe * MV-algebra Subject RIV: BA - General Mathematics Impact factor: 1.039, year: 2005

  14. The Probable Ages of Asteroid Families

    Science.gov (United States)

    Harris, A. W.

    1993-01-01

    There has been considerable debate recently over the ages of the Hirayama families, and in particular if some of the families are very oung(u) It is a straightforward task to estimate the characteristic time of a collision between a body of a given diameter, d_o, by another body of diameter greater of equal to d_1. What is less straightforward is to estimate the critical diameter ratio, d_1/d_o, above which catastrophic disruption occurs, from which one could infer probable ages of the Hirayama families, by knowing the diameter of the parent body, d_o. One can gain some insight into the probable value of d_1/d_o, and of the likely ages of existing families, from the plot below. I have computed the characteristic time between collisions in the asteroid belt of a size ratio greater of equal to d_1/d_o, for 4 sizes of target asteroids, d_o. The solid curves to the lower right are the characteristic times for a single object...

  15. Age, Loss Minimization, and the Role of Probability for Decision-Making.

    Science.gov (United States)

    Best, Ryan; Freund, Alexandra M

    2018-04-05

    Older adults are stereotypically considered to be risk averse compared to younger age groups, although meta-analyses on age and the influence of gain/loss framing on risky choices have not found empirical evidence for age differences in risk-taking. The current study extends the investigation of age differences in risk preference by including analyses on the effect of the probability of a risky option on choices in gain versus loss situations. Participants (n = 130 adults aged 19-80 years) chose between a certain option and a risky option of varying probability in gain- and loss-framed gambles with actual monetary outcomes. Only younger adults displayed an overall framing effect. Younger and older adults responded differently to probability fluctuations depending on the framing condition. Older adults were more likely to choose the risky option as the likelihood of avoiding a larger loss increased and as the likelihood of a larger gain decreased. Younger adults responded with the opposite pattern: they were more likely to choose the risky option as the likelihood of a larger gain increased and as the likelihood of avoiding a (slightly) larger loss decreased. Results suggest that older adults are more willing to select a risky option when it increases the likelihood that larger losses be avoided, whereas younger adults are more willing to select a risky option when it allows for slightly larger gains. This finding supports expectations based on theoretical accounts of goal orientation shifting away from securing gains in younger adulthood towards maintenance and avoiding losses in older adulthood. Findings are also discussed in respect to the affective enhancement perspective and socioemotional selectivity theory. © 2018 S. Karger AG, Basel.

  16. Age replacement policy based on imperfect repair with random probability

    International Nuclear Information System (INIS)

    Lim, J.H.; Qu, Jian; Zuo, Ming J.

    2016-01-01

    In most of literatures of age replacement policy, failures before planned replacement age can be either minimally repaired or perfectly repaired based on the types of failures, cost for repairs and so on. In this paper, we propose age replacement policy based on imperfect repair with random probability. The proposed policy incorporates the case that such intermittent failure can be either minimally repaired or perfectly repaired with random probabilities. The mathematical formulas of the expected cost rate per unit time are derived for both the infinite-horizon case and the one-replacement-cycle case. For each case, we show that the optimal replacement age exists and is finite. - Highlights: • We propose a new age replacement policy with random probability of perfect repair. • We develop the expected cost per unit time. • We discuss the optimal age for replacement minimizing the expected cost rate.

  17. Statistical learning of action: the role of conditional probability.

    Science.gov (United States)

    Meyer, Meredith; Baldwin, Dare

    2011-12-01

    Identification of distinct units within a continuous flow of human action is fundamental to action processing. Such segmentation may rest in part on statistical learning. In a series of four experiments, we examined what types of statistics people can use to segment a continuous stream involving many brief, goal-directed action elements. The results of Experiment 1 showed no evidence for sensitivity to conditional probability, whereas Experiment 2 displayed learning based on joint probability. In Experiment 3, we demonstrated that additional exposure to the input failed to engender sensitivity to conditional probability. However, the results of Experiment 4 showed that a subset of adults-namely, those more successful at identifying actions that had been seen more frequently than comparison sequences-were also successful at learning conditional-probability statistics. These experiments help to clarify the mechanisms subserving processing of intentional action, and they highlight important differences from, as well as similarities to, prior studies of statistical learning in other domains, including language.

  18. Toward a generalized probability theory: conditional probabilities

    International Nuclear Information System (INIS)

    Cassinelli, G.

    1979-01-01

    The main mathematical object of interest in the quantum logic approach to the foundations of quantum mechanics is the orthomodular lattice and a set of probability measures, or states, defined by the lattice. This mathematical structure is studied per se, independently from the intuitive or physical motivation of its definition, as a generalized probability theory. It is thought that the building-up of such a probability theory could eventually throw light on the mathematical structure of Hilbert-space quantum mechanics as a particular concrete model of the generalized theory. (Auth.)

  19. Smoothing and projecting age-specific probabilities of death by TOPALS

    Directory of Open Access Journals (Sweden)

    Joop de Beer

    2012-10-01

    Full Text Available BACKGROUND TOPALS is a new relational model for smoothing and projecting age schedules. The model is operationally simple, flexible, and transparent. OBJECTIVE This article demonstrates how TOPALS can be used for both smoothing and projecting age-specific mortality for 26 European countries and compares the results of TOPALS with those of other smoothing and projection methods. METHODS TOPALS uses a linear spline to describe the ratios between the age-specific death probabilities of a given country and a standard age schedule. For smoothing purposes I use the average of death probabilities over 15 Western European countries as standard, whereas for projection purposes I use an age schedule of 'best practice' mortality. A partial adjustment model projects how quickly the death probabilities move in the direction of the best-practice level of mortality. RESULTS On average, TOPALS performs better than the Heligman-Pollard model and the Brass relational method in smoothing mortality age schedules. TOPALS can produce projections that are similar to those of the Lee-Carter method, but can easily be used to produce alternative scenarios as well. This article presents three projections of life expectancy at birth for the year 2060 for 26 European countries. The Baseline scenario assumes a continuation of the past trend in each country, the Convergence scenario assumes that there is a common trend across European countries, and the Acceleration scenario assumes that the future decline of death probabilities will exceed that in the past. The Baseline scenario projects that average European life expectancy at birth will increase to 80 years for men and 87 years for women in 2060, whereas the Acceleration scenario projects an increase to 90 and 93 years respectively. CONCLUSIONS TOPALS is a useful new tool for demographers for both smoothing age schedules and making scenarios.

  20. Dental age estimation: the role of probability estimates at the 10 year threshold.

    Science.gov (United States)

    Lucas, Victoria S; McDonald, Fraser; Neil, Monica; Roberts, Graham

    2014-08-01

    The use of probability at the 18 year threshold has simplified the reporting of dental age estimates for emerging adults. The availability of simple to use widely available software has enabled the development of the probability threshold for individual teeth in growing children. Tooth development stage data from a previous study at the 10 year threshold were reused to estimate the probability of developing teeth being above or below the 10 year thresh-hold using the NORMDIST Function in Microsoft Excel. The probabilities within an individual subject are averaged to give a single probability that a subject is above or below 10 years old. To test the validity of this approach dental panoramic radiographs of 50 female and 50 male children within 2 years of the chronological age were assessed with the chronological age masked. Once the whole validation set of 100 radiographs had been assessed the masking was removed and the chronological age and dental age compared. The dental age was compared with chronological age to determine whether the dental age correctly or incorrectly identified a validation subject as above or below the 10 year threshold. The probability estimates correctly identified children as above or below on 94% of occasions. Only 2% of the validation group with a chronological age of less than 10 years were assigned to the over 10 year group. This study indicates the very high accuracy of assignment at the 10 year threshold. Further work at other legally important age thresholds is needed to explore the value of this approach to the technique of age estimation. Copyright © 2014. Published by Elsevier Ltd.

  1. Modeling highway travel time distribution with conditional probability models

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Neto, Francisco Moraes [ORNL; Chin, Shih-Miao [ORNL; Hwang, Ho-Ling [ORNL; Han, Lee [University of Tennessee, Knoxville (UTK)

    2014-01-01

    ABSTRACT Under the sponsorship of the Federal Highway Administration's Office of Freight Management and Operations, the American Transportation Research Institute (ATRI) has developed performance measures through the Freight Performance Measures (FPM) initiative. Under this program, travel speed information is derived from data collected using wireless based global positioning systems. These telemetric data systems are subscribed and used by trucking industry as an operations management tool. More than one telemetric operator submits their data dumps to ATRI on a regular basis. Each data transmission contains truck location, its travel time, and a clock time/date stamp. Data from the FPM program provides a unique opportunity for studying the upstream-downstream speed distributions at different locations, as well as different time of the day and day of the week. This research is focused on the stochastic nature of successive link travel speed data on the continental United States Interstates network. Specifically, a method to estimate route probability distributions of travel time is proposed. This method uses the concepts of convolution of probability distributions and bivariate, link-to-link, conditional probability to estimate the expected distributions for the route travel time. Major contribution of this study is the consideration of speed correlation between upstream and downstream contiguous Interstate segments through conditional probability. The established conditional probability distributions, between successive segments, can be used to provide travel time reliability measures. This study also suggests an adaptive method for calculating and updating route travel time distribution as new data or information is added. This methodology can be useful to estimate performance measures as required by the recent Moving Ahead for Progress in the 21st Century Act (MAP 21).

  2. Conditional Probabilities in the Excursion Set Theory. Generic Barriers and non-Gaussian Initial Conditions

    CERN Document Server

    De Simone, Andrea; Riotto, Antonio

    2011-01-01

    The excursion set theory, where density perturbations evolve stochastically with the smoothing scale, provides a method for computing the dark matter halo mass function. The computation of the mass function is mapped into the so-called first-passage time problem in the presence of a moving barrier. The excursion set theory is also a powerful formalism to study other properties of dark matter halos such as halo bias, accretion rate, formation time, merging rate and the formation history of halos. This is achieved by computing conditional probabilities with non-trivial initial conditions, and the conditional two-barrier first-crossing rate. In this paper we use the recently-developed path integral formulation of the excursion set theory to calculate analytically these conditional probabilities in the presence of a generic moving barrier, including the one describing the ellipsoidal collapse, and for both Gaussian and non-Gaussian initial conditions. The non-Markovianity of the random walks induced by non-Gaussi...

  3. Decomposition of conditional probability for high-order symbolic Markov chains

    Science.gov (United States)

    Melnik, S. S.; Usatenko, O. V.

    2017-07-01

    The main goal of this paper is to develop an estimate for the conditional probability function of random stationary ergodic symbolic sequences with elements belonging to a finite alphabet. We elaborate on a decomposition procedure for the conditional probability function of sequences considered to be high-order Markov chains. We represent the conditional probability function as the sum of multilinear memory function monomials of different orders (from zero up to the chain order). This allows us to introduce a family of Markov chain models and to construct artificial sequences via a method of successive iterations, taking into account at each step increasingly high correlations among random elements. At weak correlations, the memory functions are uniquely expressed in terms of the high-order symbolic correlation functions. The proposed method fills the gap between two approaches, namely the likelihood estimation and the additive Markov chains. The obtained results may have applications for sequential approximation of artificial neural network training.

  4. Probability, conditional probability and complementary cumulative distribution functions in performance assessment for radioactive waste disposal

    International Nuclear Information System (INIS)

    Helton, J.C.

    1996-03-01

    A formal description of the structure of several recent performance assessments (PAs) for the Waste Isolation Pilot Plant (WIPP) is given in terms of the following three components: a probability space (S st , S st , p st ) for stochastic uncertainty, a probability space (S su , S su , p su ) for subjective uncertainty and a function (i.e., a random variable) defined on the product space associated with (S st , S st , p st ) and (S su , S su , p su ). The explicit recognition of the existence of these three components allows a careful description of the use of probability, conditional probability and complementary cumulative distribution functions within the WIPP PA. This usage is illustrated in the context of the U.S. Environmental Protection Agency's standard for the geologic disposal of radioactive waste (40 CFR 191, Subpart B). The paradigm described in this presentation can also be used to impose a logically consistent structure on PAs for other complex systems

  5. Probability, conditional probability and complementary cumulative distribution functions in performance assessment for radioactive waste disposal

    International Nuclear Information System (INIS)

    Helton, J.C.

    1996-01-01

    A formal description of the structure of several recent performance assessments (PAs) for the Waste Isolation Pilot Plant (WIPP) is given in terms of the following three components: a probability space (S st , L st , P st ) for stochastic uncertainty, a probability space (S su , L su , P su ) for subjective uncertainty and a function (i.e., a random variable) defined on the product space associated with (S st , L st , P st ) and (S su , L su , P su ). The explicit recognition of the existence of these three components allows a careful description of the use of probability, conditional probability and complementary cumulative distribution functions within the WIPP PA. This usage is illustrated in the context of the US Environmental Protection Agency's standard for the geologic disposal of radioactive waste (40 CFR 191, Subpart B). The paradigm described in this presentation can also be used to impose a logically consistent structure on PAs for other complex systems

  6. Statistical models based on conditional probability distributions

    International Nuclear Information System (INIS)

    Narayanan, R.S.

    1991-10-01

    We present a formulation of statistical mechanics models based on conditional probability distribution rather than a Hamiltonian. We show that it is possible to realize critical phenomena through this procedure. Closely linked with this formulation is a Monte Carlo algorithm, in which a configuration generated is guaranteed to be statistically independent from any other configuration for all values of the parameters, in particular near the critical point. (orig.)

  7. Experiencing El Niño conditions during early life reduces recruiting probabilities but not adult survival

    Science.gov (United States)

    Rodríguez, Cristina; Drummond, Hugh

    2018-01-01

    In wild long-lived animals, analysis of impacts of stressful natal conditions on adult performance has rarely embraced the entire age span, and the possibility that costs are expressed late in life has seldom been examined. Using 26 years of data from 8541 fledglings and 1310 adults of the blue-footed booby (Sula nebouxii), a marine bird that can live up to 23 years, we tested whether experiencing the warm waters and food scarcity associated with El Niño in the natal year reduces recruitment or survival over the adult lifetime. Warm water in the natal year reduced the probability of recruiting; each additional degree (°C) of water temperature meant a reduction of roughly 50% in fledglings' probability of returning to the natal colony as breeders. Warm water in the current year impacted adult survival, with greater effect at the oldest ages than during early adulthood. However, warm water in the natal year did not affect survival at any age over the adult lifespan. A previous study showed that early recruitment and widely spaced breeding allow boobies that experience warm waters in the natal year to achieve normal fledgling production over the first 10 years; our results now show that this reproductive effort incurs no survival penalty, not even late in life. This pattern is additional evidence of buffering against stressful natal conditions via life-history adjustments. PMID:29410788

  8. Probability, conditional probability and complementary cumulative distribution functions in performance assessment for radioactive waste disposal

    Energy Technology Data Exchange (ETDEWEB)

    Helton, J.C. [Arizona State Univ., Tempe, AZ (United States)

    1996-03-01

    A formal description of the structure of several recent performance assessments (PAs) for the Waste Isolation Pilot Plant (WIPP) is given in terms of the following three components: a probability space (S{sub st}, S{sub st}, p{sub st}) for stochastic uncertainty, a probability space (S{sub su}, S{sub su}, p{sub su}) for subjective uncertainty and a function (i.e., a random variable) defined on the product space associated with (S{sub st}, S{sub st}, p{sub st}) and (S{sub su}, S{sub su}, p{sub su}). The explicit recognition of the existence of these three components allows a careful description of the use of probability, conditional probability and complementary cumulative distribution functions within the WIPP PA. This usage is illustrated in the context of the U.S. Environmental Protection Agency`s standard for the geologic disposal of radioactive waste (40 CFR 191, Subpart B). The paradigm described in this presentation can also be used to impose a logically consistent structure on PAs for other complex systems.

  9. Conditional Probability Analysis: A Statistical Tool for Environmental Analysis.

    Science.gov (United States)

    The use and application of environmental conditional probability analysis (CPA) is relatively recent. The first presentation using CPA was made in 2002 at the New England Association of Environmental Biologists Annual Meeting in Newport. Rhode Island. CPA has been used since the...

  10. Conditional probability of the tornado missile impact given a tornado occurrence

    International Nuclear Information System (INIS)

    Goodman, J.; Koch, J.E.

    1982-01-01

    Using an approach based on statistical mechanics, an expression for the probability of the first missile strike is developed. The expression depends on two generic parameters (injection probability eta(F) and height distribution psi(Z,F)), which are developed in this study, and one plant specific parameter (number of potential missiles N/sub p/). The expression for the joint probability of simultaneous impact of muitiple targets is also developed. This espression is applicable to calculation of the probability of common cause failure due to tornado missiles. It is shown that the probability of the first missile strike can be determined using a uniform missile distribution model. It is also shown that the conditional probability of the second strike, given the first, is underestimated by the uniform model. The probability of the second strike is greatly increased if the missiles are in clusters large enough to cover both targets

  11. Study on conditional probability of surface rupture: effect of fault dip and width of seismogenic layer

    Science.gov (United States)

    Inoue, N.

    2017-12-01

    The conditional probability of surface ruptures is affected by various factors, such as shallow material properties, process of earthquakes, ground motions and so on. Toda (2013) pointed out difference of the conditional probability of strike and reverse fault by considering the fault dip and width of seismogenic layer. This study evaluated conditional probability of surface rupture based on following procedures. Fault geometry was determined from the randomly generated magnitude based on The Headquarters for Earthquake Research Promotion (2017) method. If the defined fault plane was not saturated in the assumed width of the seismogenic layer, the fault plane depth was randomly provided within the seismogenic layer. The logistic analysis was performed to two data sets: surface displacement calculated by dislocation methods (Wang et al., 2003) from the defined source fault, the depth of top of the defined source fault. The estimated conditional probability from surface displacement indicated higher probability of reverse faults than that of strike faults, and this result coincides to previous similar studies (i.e. Kagawa et al., 2004; Kataoka and Kusakabe, 2005). On the contrary, the probability estimated from the depth of the source fault indicated higher probability of thrust faults than that of strike and reverse faults, and this trend is similar to the conditional probability of PFDHA results (Youngs et al., 2003; Moss and Ross, 2011). The probability of combined simulated results of thrust and reverse also shows low probability. The worldwide compiled reverse fault data include low fault dip angle earthquake. On the other hand, in the case of Japanese reverse fault, there is possibility that the conditional probability of reverse faults with less low dip angle earthquake shows low probability and indicates similar probability of strike fault (i.e. Takao et al., 2013). In the future, numerical simulation by considering failure condition of surface by the source

  12. Comparison of clinical probability-adjusted D-dimer and age-adjusted D-dimer interpretation to exclude venous thromboembolism.

    Science.gov (United States)

    Takach Lapner, Sarah; Julian, Jim A; Linkins, Lori-Ann; Bates, Shannon; Kearon, Clive

    2017-10-05

    Two new strategies for interpreting D-dimer results have been proposed: i) using a progressively higher D-dimer threshold with increasing age (age-adjusted strategy) and ii) using a D-dimer threshold in patients with low clinical probability that is twice the threshold used in patients with moderate clinical probability (clinical probability-adjusted strategy). Our objective was to compare the diagnostic accuracy of age-adjusted and clinical probability-adjusted D-dimer interpretation in patients with a low or moderate clinical probability of venous thromboembolism (VTE). We performed a retrospective analysis of clinical data and blood samples from two prospective studies. We compared the negative predictive value (NPV) for VTE, and the proportion of patients with a negative D-dimer result, using two D-dimer interpretation strategies: the age-adjusted strategy, which uses a progressively higher D-dimer threshold with increasing age over 50 years (age in years × 10 µg/L FEU); and the clinical probability-adjusted strategy which uses a D-dimer threshold of 1000 µg/L FEU in patients with low clinical probability and 500 µg/L FEU in patients with moderate clinical probability. A total of 1649 outpatients with low or moderate clinical probability for a first suspected deep vein thrombosis or pulmonary embolism were included. The NPV of both the clinical probability-adjusted strategy (99.7 %) and the age-adjusted strategy (99.6 %) were similar. However, the proportion of patients with a negative result was greater with the clinical probability-adjusted strategy (56.1 % vs, 50.9 %; difference 5.2 %; 95 % CI 3.5 % to 6.8 %). These findings suggest that clinical probability-adjusted D-dimer interpretation is a better way of interpreting D-dimer results compared to age-adjusted interpretation.

  13. An Alternative Teaching Method of Conditional Probabilities and Bayes' Rule: An Application of the Truth Table

    Science.gov (United States)

    Satake, Eiki; Vashlishan Murray, Amy

    2015-01-01

    This paper presents a comparison of three approaches to the teaching of probability to demonstrate how the truth table of elementary mathematical logic can be used to teach the calculations of conditional probabilities. Students are typically introduced to the topic of conditional probabilities--especially the ones that involve Bayes' rule--with…

  14. The limiting conditional probability distribution in a stochastic model of T cell repertoire maintenance.

    Science.gov (United States)

    Stirk, Emily R; Lythe, Grant; van den Berg, Hugo A; Hurst, Gareth A D; Molina-París, Carmen

    2010-04-01

    The limiting conditional probability distribution (LCD) has been much studied in the field of mathematical biology, particularly in the context of epidemiology and the persistence of epidemics. However, it has not yet been applied to the immune system. One of the characteristic features of the T cell repertoire is its diversity. This diversity declines in old age, whence the concepts of extinction and persistence are also relevant to the immune system. In this paper we model T cell repertoire maintenance by means of a continuous-time birth and death process on the positive integers, where the origin is an absorbing state. We show that eventual extinction is guaranteed. The late-time behaviour of the process before extinction takes place is modelled by the LCD, which we prove always exists for the process studied here. In most cases, analytic expressions for the LCD cannot be computed but the probability distribution may be approximated by means of the stationary probability distributions of two related processes. We show how these approximations are related to the LCD of the original process and use them to study the LCD in two special cases. We also make use of the large N expansion to derive a further approximation to the LCD. The accuracy of the various approximations is then analysed. (c) 2009 Elsevier Inc. All rights reserved.

  15. Calculation of the Incremental Conditional Core Damage Probability on the Extension of Allowed Outage Time

    International Nuclear Information System (INIS)

    Kang, Dae Il; Han, Sang Hoon

    2006-01-01

    RG 1.177 requires that the conditional risk (incremental conditional core damage probability and incremental conditional large early release probability: ICCDP and ICLERP), given that a specific component is out of service (OOS), be quantified for a permanent change of the allowed outage time (AOT) of a safety system. An AOT is the length of time that a particular component or system is permitted to be OOS while the plant is operating. The ICCDP is defined as: ICCDP = [(conditional CDF with the subject equipment OOS)- (baseline CDF with nominal expected equipment unavailabilities)] [duration of the single AOT under consideration]. Any event enabling the component OOS can initiate the time clock for the limiting condition of operation for a nuclear power plant. Thus, the largest ICCDP among the ICCDPs estimated from any occurrence of the basic events for the component fault tree should be selected for determining whether the AOT can be extended or not. If the component is under a preventive maintenance, the conditional risk can be straightforwardly calculated without changing the CCF probability. The main concern is the estimations of the CCF probability because there are the possibilities of the failures of other similar components due to the same root causes. The quantifications of the risk, given that a subject equipment is in a failed state, are performed by setting the identified event of subject equipment to TRUE. The CCF probabilities are also changed according to the identified failure cause. In the previous studies, however, the ICCDP was quantified with the consideration of the possibility of a simultaneous occurrence of two CCF events. Based on the above, we derived the formulas of the CCF probabilities for the cases where a specific component is in a failed state and we presented sample calculation results of the ICCDP for the low pressure safety injection system (LPSIS) of Ulchin Unit 3

  16. Using Dynamic Geometry Software for Teaching Conditional Probability with Area-Proportional Venn Diagrams

    Science.gov (United States)

    Radakovic, Nenad; McDougall, Douglas

    2012-01-01

    This classroom note illustrates how dynamic visualization can be used to teach conditional probability and Bayes' theorem. There are two features of the visualization that make it an ideal pedagogical tool in probability instruction. The first feature is the use of area-proportional Venn diagrams that, along with showing qualitative relationships,…

  17. Class dependency of fuzzy relational database using relational calculus and conditional probability

    Science.gov (United States)

    Deni Akbar, Mohammad; Mizoguchi, Yoshihiro; Adiwijaya

    2018-03-01

    In this paper, we propose a design of fuzzy relational database to deal with a conditional probability relation using fuzzy relational calculus. In the previous, there are several researches about equivalence class in fuzzy database using similarity or approximate relation. It is an interesting topic to investigate the fuzzy dependency using equivalence classes. Our goal is to introduce a formulation of a fuzzy relational database model using the relational calculus on the category of fuzzy relations. We also introduce general formulas of the relational calculus for the notion of database operations such as ’projection’, ’selection’, ’injection’ and ’natural join’. Using the fuzzy relational calculus and conditional probabilities, we introduce notions of equivalence class, redundant, and dependency in the theory fuzzy relational database.

  18. [Conditional probability analysis between tinnitus and comorbidities in patients attending the National Rehabilitation Institute-LGII in the period 2012-2013].

    Science.gov (United States)

    Gómez Toledo, Verónica; Gutiérrez Farfán, Ileana; Verduzco-Mendoza, Antonio; Arch-Tirado, Emilio

    Tinnitus is defined as the conscious perception of a sensation of sound that occurs in the absence of an external stimulus. This audiological symptom affects 7% to 19% of the adult population. The aim of this study is to describe the associated comorbidities present in patients with tinnitus usingjoint and conditional probability analysis. Patients of both genders, diagnosed with unilateral or bilateral tinnitus, aged between 20 and 45 years, and had a full computerised medical record, were selected. Study groups were formed on the basis of the following clinical aspects: 1) audiological findings; 2) vestibular findings; 3) comorbidities such as, temporomandibular dysfunction, tubal dysfunction, otosclerosis and, 4) triggering factors of tinnitus noise exposure, respiratory tract infection, use of ototoxic and/or drugs. Of the patients with tinnitus, 27 (65%) reported hearing loss, 11 (26.19%) temporomandibular dysfunction, and 11 (26.19%) with vestibular disorders. When performing the joint probability analysis, it was found that the probability that a patient with tinnitus having hearing loss was 2742 0.65, and 2042 0.47 for bilateral type. The result for P (A ∩ B)=30%. Bayes' theorem P (AiB) = P(Ai∩B)P(B) was used, and various probabilities were calculated. Therefore, in patients with temporomandibulardysfunction and vestibular disorders, a posterior probability of P (Aі/B)=31.44% was calculated. Consideration should be given to the joint and conditional probability approach as tools for the study of different pathologies. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  19. Stage line diagram: an age-conditional reference diagram for tracking development.

    Science.gov (United States)

    van Buuren, Stef; Ooms, Jeroen C L

    2009-05-15

    This paper presents a method for calculating stage line diagrams, a novel type of reference diagram useful for tracking developmental processes over time. Potential fields of applications include: dentistry (tooth eruption), oncology (tumor grading, cancer staging), virology (HIV infection and disease staging), psychology (stages of cognitive development), human development (pubertal stages) and chronic diseases (stages of dementia). Transition probabilities between successive stages are modeled as smoothly varying functions of age. Age-conditional references are calculated from the modeled probabilities by the mid-P value. It is possible to eliminate the influence of age by calculating standard deviation scores (SDS). The method is applied to the empirical data to produce reference charts on secondary sexual maturation. The mean of the empirical SDS in the reference population is close to zero, whereas the variance depends on age. The stage line diagram provides quick insight into both status (in SDS) and tempo (in SDS/year) of development of an individual child. Other measures (e.g. height SDS, body mass index SDS) from the same child can be added to the chart. Diagrams for sexual maturation are available as a web application at http://vps.stefvanbuuren.nl/puberty. The stage line diagram expresses status and tempo of discrete changes on a continuous scale. Wider application of these measures scores opens up new analytic possibilities. (c) 2009 John Wiley & Sons, Ltd.

  20. Conditional probability of intense rainfall producing high ground concentrations from radioactive plumes

    International Nuclear Information System (INIS)

    Wayland, J.R.

    1977-03-01

    The overlap of the expanding plume of radioactive material from a hypothetical nuclear accident with rainstorms over dense population areas is considered. The conditional probability of the occurrence of hot spots from intense cellular rainfall is presented

  1. The effect of conditional probability of chord progression on brain response: an MEG study.

    Directory of Open Access Journals (Sweden)

    Seung-Goo Kim

    Full Text Available BACKGROUND: Recent electrophysiological and neuroimaging studies have explored how and where musical syntax in Western music is processed in the human brain. An inappropriate chord progression elicits an event-related potential (ERP component called an early right anterior negativity (ERAN or simply an early anterior negativity (EAN in an early stage of processing the musical syntax. Though the possible underlying mechanism of the EAN is assumed to be probabilistic learning, the effect of the probability of chord progressions on the EAN response has not been previously explored explicitly. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, the empirical conditional probabilities in a Western music corpus were employed as an approximation of the frequencies in previous exposure of participants. Three types of chord progression were presented to musicians and non-musicians in order to examine the correlation between the probability of chord progression and the neuromagnetic response using magnetoencephalography (MEG. Chord progressions were found to elicit early responses in a negatively correlating fashion with the conditional probability. Observed EANm (as a magnetic counterpart of the EAN component responses were consistent with the previously reported EAN responses in terms of latency and location. The effect of conditional probability interacted with the effect of musical training. In addition, the neural response also correlated with the behavioral measures in the non-musicians. CONCLUSIONS/SIGNIFICANCE: Our study is the first to reveal the correlation between the probability of chord progression and the corresponding neuromagnetic response. The current results suggest that the physiological response is a reflection of the probabilistic representations of the musical syntax. Moreover, the results indicate that the probabilistic representation is related to the musical training as well as the sensitivity of an individual.

  2. Individual quality and age but not environmental or social conditions modulate costs of reproduction in a capital breeder.

    Science.gov (United States)

    Debeffe, Lucie; Poissant, Jocelyn; McLoughlin, Philip D

    2017-08-01

    Costs associated with reproduction are widely known to play a role in the evolution of reproductive tactics with consequences to population and eco-evolutionary dynamics. Evaluating these costs as they pertain to species in the wild remains an important goal of evolutionary ecology. Individual heterogeneity, including differences in individual quality (i.e., among-individual differences in traits associated with survival and reproduction) or state, and variation in environmental and social conditions can modulate the costs of reproduction; however, few studies have considered effects of these factors simultaneously. Taking advantage of a detailed, long-term dataset for a population of feral horses (Sable Island, Nova Scotia, Canada), we address the question of how intrinsic (quality, age), environmental (winter severity, location), and social conditions (group size, composition, sex ratio, density) influence the costs of reproduction on subsequent reproduction. Individual quality was measured using a multivariate analysis on a combination of four static and dynamic traits expected to depict heterogeneity in individual performance. Female quality and age interacted with reproductive status of the previous year to determine current reproductive effort, while no effect of social or environmental covariates was found. High-quality females showed higher probabilities of giving birth and weaning their foal regardless of their reproductive status the previous year, while those of lower quality showed lower probabilities of producing foals in successive years. Middle-aged (prime) females had the highest probability of giving birth when they had not reproduced the year before, but no such relationship with age was found among females that had reproduced the previous year, indicating that prime-aged females bear higher costs of reproduction. We show that individual quality and age were key factors modulating the costs of reproduction in a capital breeder but that

  3. Classic conditioning in aged rabbits: delay, trace, and long-delay conditioning.

    Science.gov (United States)

    Solomon, P R; Groccia-Ellison, M E

    1996-06-01

    Young (0.5 years) and aged (2+, 3+, and 4+ years) rabbits underwent acquisition of the classically conditioned nictitating membrane response in a delay (500-ms conditioned stimulus [CS], 400-ms interstimulus interval [ISI]), long-delay (1,000-ms CS, 900-ms ISI), or trace (500-ms CS, 400-ms stimulus-free period) paradigm. Collapsing across age groups, there is a general tendency for animals to acquire trace conditioning more slowly than delay conditioning. Collapsing across conditioning paradigms, there is a general tendency for aged animals to acquire more slowly than younger animals. Of greater significance, however, are the age differences in the different conditioning paradigms. In the delay and long-delay paradigms, significant conditioning deficits first appeared in the 4(+)-year-old group. In the trace conditioning paradigm, significant conditioning deficits became apparent in the 2(+)-year-old animals.

  4. Quantum-correlation breaking channels, quantum conditional probability and Perron-Frobenius theory

    Science.gov (United States)

    Chruściński, Dariusz

    2013-03-01

    Using the quantum analog of conditional probability and classical Bayes theorem we discuss some aspects of particular entanglement breaking channels: quantum-classical and classical-classical channels. Applying the quantum analog of Perron-Frobenius theorem we generalize the recent result of Korbicz et al. (2012) [8] on full and spectrum broadcasting from quantum-classical channels to arbitrary quantum channels.

  5. Quantum-correlation breaking channels, quantum conditional probability and Perron–Frobenius theory

    International Nuclear Information System (INIS)

    Chruściński, Dariusz

    2013-01-01

    Using the quantum analog of conditional probability and classical Bayes theorem we discuss some aspects of particular entanglement breaking channels: quantum–classical and classical–classical channels. Applying the quantum analog of Perron–Frobenius theorem we generalize the recent result of Korbicz et al. (2012) [8] on full and spectrum broadcasting from quantum–classical channels to arbitrary quantum channels.

  6. Probability of developing severe sepsis in patients of elderly and senile age with necrotic erysipelas

    Directory of Open Access Journals (Sweden)

    Shapkin Yu.G.

    2015-06-01

    Full Text Available Objective: the probable determination of severe sepsis in patients of elderly and senile age with necrotic erysipelas based on a comprehensive assessment (clinical examination using systems — scales and determination of the level markers of SIRS. Material and methods. The analysis of peculiarities of necrotic erysipelas clinical course in 59 patients. The first group consisted of 17 patients with severe sepsis, the second — 18 patients with sepsis without multiple organ failure, in the comparison group —22 patients with local infection. We determined albumin, urea, creatinine, pro-calcitonin of plasma. The scale SAPS III was used to quantify SIRS, scale SOFA —to determine the extent of damage to organs and systems. Results. The most sensitive marker of developing sepsis in patients with necrotic erysipelas was procalcitonin. The second important indicator of SIRS severity in patients with necrotic erysipelas was the blood albumin. Scale SAPS III also allows to select a group of patients with high risk of developing severe sepsis. Use of the SOFA to predict the scale has been found out to be less important. Conclusion. A comprehensive assessment of the severity of the condition by scale SAPS III in combination with determining the levels of procalcitonin and plasma albumin is advisable to apply for prediction the probability of developing severe sepsis in patients of elderly and senile age with necrotic erysipelas. For the last indicator it is important to assess of absolute values and the decrease of its concentration.

  7. Eliciting conditional and unconditional rank correlations from conditional probabilities

    International Nuclear Information System (INIS)

    Morales, O.; Kurowicka, D.; Roelen, A.

    2008-01-01

    Causes of uncertainties may be interrelated and may introduce dependencies. Ignoring these dependencies may lead to large errors. A number of graphical models in probability theory such as dependence trees, vines and (continuous) Bayesian belief nets [Cooke RM. Markov and entropy properties of tree and vine-dependent variables. In: Proceedings of the ASA section on Bayesian statistical science, 1997; Kurowicka D, Cooke RM. Distribution-free continuous Bayesian belief nets. In: Proceedings of mathematical methods in reliability conference, 2004; Bedford TJ, Cooke RM. Vines-a new graphical model for dependent random variables. Ann Stat 2002; 30(4):1031-68; Kurowicka D, Cooke RM. Uncertainty analysis with high dimensional dependence modelling. New York: Wiley; 2006; Hanea AM, et al. Hybrid methods for quantifying and analyzing Bayesian belief nets. In: Proceedings of the 2005 ENBIS5 conference, 2005; Shachter RD, Kenley CR. Gaussian influence diagrams. Manage Sci 1998; 35(5) .] have been developed to capture dependencies between random variables. The input for these models are various marginal distributions and dependence information, usually in the form of conditional rank correlations. Often expert elicitation is required. This paper focuses on dependence representation, and dependence elicitation. The techniques presented are illustrated with an application from aviation safety

  8. Conditional Independence in Applied Probability.

    Science.gov (United States)

    Pfeiffer, Paul E.

    This material assumes the user has the background provided by a good undergraduate course in applied probability. It is felt that introductory courses in calculus, linear algebra, and perhaps some differential equations should provide the requisite experience and proficiency with mathematical concepts, notation, and argument. The document is…

  9. Multiregion, multigroup collision probability method with white boundary condition for light water reactor thermalization calculations

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2005-01-01

    A multiregion, multigroup collision probability method with white boundary condition is developed for thermalization calculations of light water moderated reactors. Hydrogen scatterings are treated by Nelkin's kernel while scatterings from other nuclei are assumed to obey the free-gas scattering kernel. The isotropic return (white) boundary condition is applied directly by using the appropriate collision probabilities. Comparisons with alternate numerical methods show the validity of the present formulation. Comparisons with some experimental results indicate that the present formulation is capable of calculating disadvantage factors which are closer to the experimental results than alternative methods

  10. A probability evaluation method of early deterioration condition for the critical components of wind turbine generator systems

    DEFF Research Database (Denmark)

    Hu, Y.; Li, H.; Liao, X

    2016-01-01

    method of early deterioration condition for critical components based only on temperature characteristic parameters. First, the dynamic threshold of deterioration degree function was proposed by analyzing the operational data between temperature and rotor speed. Second, a probability evaluation method...... of early deterioration condition was presented. Finally, two cases showed the validity of the proposed probability evaluation method in detecting early deterioration condition and in tracking their further deterioration for the critical components.......This study determines the early deterioration condition of critical components for a wind turbine generator system (WTGS). Due to the uncertainty nature of the fluctuation and intermittence of wind, early deterioration condition evaluation poses a challenge to the traditional vibration...

  11. The Probability of Neonatal Respiratory Distress Syndrome as a Function of Gestational Age and Lecithin/Sphingomyelin Ratio

    Science.gov (United States)

    St. Clair, Caryn; Norwitz, Errol R.; Woensdregt, Karlijn; Cackovic, Michael; Shaw, Julia A.; Malkus, Herbert; Ehrenkranz, Richard A.; Illuzzi, Jessica L.

    2011-01-01

    We sought to define the risk of neonatal respiratory distress syndrome (RDS) as a function of both lecithin/sphingomyelin (L/S) ratio and gestational age. Amniotic fluid L/S ratio data were collected from consecutive women undergoing amniocentesis for fetal lung maturity at Yale-New Haven Hospital from January 1998 to December 2004. Women were included in the study if they delivered a live-born, singleton, nonanomalous infant within 72 hours of amniocentesis. The probability of RDS was modeled using multivariate logistic regression with L/S ratio and gestational age as predictors. A total of 210 mother-neonate pairs (8 RDS, 202 non-RDS) met criteria for analysis. Both gestational age and L/S ratio were independent predictors of RDS. A probability of RDS of 3% or less was noted at an L/S ratio cutoff of ≥3.4 at 34 weeks, ≥2.6 at 36 weeks, ≥1.6 at 38 weeks, and ≥1.2 at term. Under 34 weeks of gestation, the prevalence of RDS was so high that a probability of 3% or less was not observed by this model. These data describe a means of stratifying the probability of neonatal RDS using both gestational age and the L/S ratio and may aid in clinical decision making concerning the timing of delivery. PMID:18773379

  12. Heightened fire probability in Indonesia in non-drought conditions: the effect of increasing temperatures

    Science.gov (United States)

    Fernandes, Kátia; Verchot, Louis; Baethgen, Walter; Gutierrez-Velez, Victor; Pinedo-Vasquez, Miguel; Martius, Christopher

    2017-05-01

    In Indonesia, drought driven fires occur typically during the warm phase of the El Niño Southern Oscillation. This was the case of the events of 1997 and 2015 that resulted in months-long hazardous atmospheric pollution levels in Equatorial Asia and record greenhouse gas emissions. Nonetheless, anomalously active fire seasons have also been observed in non-drought years. In this work, we investigated the impact of temperature on fires and found that when the July-October (JASO) period is anomalously dry, the sensitivity of fires to temperature is modest. In contrast, under normal-to-wet conditions, fire probability increases sharply when JASO is anomalously warm. This describes a regime in which an active fire season is not limited to drought years. Greater susceptibility to fires in response to a warmer environment finds support in the high evapotranspiration rates observed in normal-to-wet and warm conditions in Indonesia. We also find that fire probability in wet JASOs would be considerably less sensitive to temperature were not for the added effect of recent positive trends. Near-term regional climate projections reveal that, despite negligible changes in precipitation, a continuing warming trend will heighten fire probability over the next few decades especially in non-drought years. Mild fire seasons currently observed in association with wet conditions and cool temperatures will become rare events in Indonesia.

  13. Estimation of submarine mass failure probability from a sequence of deposits with age dates

    Science.gov (United States)

    Geist, Eric L.; Chaytor, Jason D.; Parsons, Thomas E.; ten Brink, Uri S.

    2013-01-01

    The empirical probability of submarine mass failure is quantified from a sequence of dated mass-transport deposits. Several different techniques are described to estimate the parameters for a suite of candidate probability models. The techniques, previously developed for analyzing paleoseismic data, include maximum likelihood and Type II (Bayesian) maximum likelihood methods derived from renewal process theory and Monte Carlo methods. The estimated mean return time from these methods, unlike estimates from a simple arithmetic mean of the center age dates and standard likelihood methods, includes the effects of age-dating uncertainty and of open time intervals before the first and after the last event. The likelihood techniques are evaluated using Akaike’s Information Criterion (AIC) and Akaike’s Bayesian Information Criterion (ABIC) to select the optimal model. The techniques are applied to mass transport deposits recorded in two Integrated Ocean Drilling Program (IODP) drill sites located in the Ursa Basin, northern Gulf of Mexico. Dates of the deposits were constrained by regional bio- and magnetostratigraphy from a previous study. Results of the analysis indicate that submarine mass failures in this location occur primarily according to a Poisson process in which failures are independent and return times follow an exponential distribution. However, some of the model results suggest that submarine mass failures may occur quasiperiodically at one of the sites (U1324). The suite of techniques described in this study provides quantitative probability estimates of submarine mass failure occurrence, for any number of deposits and age uncertainty distributions.

  14. Know the risk, take the win: how executive functions and probability processing influence advantageous decision making under risk conditions.

    Science.gov (United States)

    Brand, Matthias; Schiebener, Johannes; Pertl, Marie-Theres; Delazer, Margarete

    2014-01-01

    Recent models on decision making under risk conditions have suggested that numerical abilities are important ingredients of advantageous decision-making performance, but empirical evidence is still limited. The results of our first study show that logical reasoning and basic mental calculation capacities predict ratio processing and that ratio processing predicts decision making under risk. In the second study, logical reasoning together with executive functions predicted probability processing (numeracy and probability knowledge), and probability processing predicted decision making under risk. These findings suggest that increasing an individual's understanding of ratios and probabilities should lead to more advantageous decisions under risk conditions.

  15. Hawkes-diffusion process and the conditional probability of defaults in the Eurozone

    Science.gov (United States)

    Kim, Jungmu; Park, Yuen Jung; Ryu, Doojin

    2016-05-01

    This study examines market information embedded in the European sovereign CDS (credit default swap) market by analyzing the sovereign CDSs of 13 Eurozone countries from January 1, 2008, to February 29, 2012, which includes the recent Eurozone debt crisis period. We design the conditional probability of defaults for the CDS prices based on the Hawkes-diffusion process and obtain the theoretical prices of CDS indexes. To estimate the model parameters, we calibrate the model prices to empirical prices obtained from individual sovereign CDS term structure data. The estimated parameters clearly explain both cross-sectional and time-series data. Our empirical results show that the probability of a huge loss event sharply increased during the Eurozone debt crisis, indicating a contagion effect. Even countries with strong and stable economies, such as Germany and France, suffered from the contagion effect. We also find that the probability of small events is sensitive to the state of the economy, spiking several times due to the global financial crisis and the Greek government debt crisis.

  16. A Hierarchy of Compatibility and Comeasurability Levels in Quantum Logics with Unique Conditional Probabilities

    International Nuclear Information System (INIS)

    Niestegge, Gerd

    2010-01-01

    In the quantum mechanical Hilbert space formalism, the probabilistic interpretation is a later ad-hoc add-on, more or less enforced by the experimental evidence, but not motivated by the mathematical model itself. A model involving a clear probabilistic interpretation from the very beginning is provided by the quantum logics with unique conditional probabilities. It includes the projection lattices in von Neumann algebras and here probability conditionalization becomes identical with the state transition of the Lueders-von Neumann measurement process. This motivates the definition of a hierarchy of five compatibility and comeasurability levels in the abstract setting of the quantum logics with unique conditional probabilities. Their meanings are: the absence of quantum interference or influence, the existence of a joint distribution, simultaneous measurability, and the independence of the final state after two successive measurements from the sequential order of these two measurements. A further level means that two elements of the quantum logic (events) belong to the same Boolean subalgebra. In the general case, the five compatibility and comeasurability levels appear to differ, but they all coincide in the common Hilbert space formalism of quantum mechanics, in von Neumann algebras, and in some other cases. (general)

  17. Foundations of probability

    International Nuclear Information System (INIS)

    Fraassen, B.C. van

    1979-01-01

    The interpretation of probabilities in physical theories are considered, whether quantum or classical. The following points are discussed 1) the functions P(μ, Q) in terms of which states and propositions can be represented, are classical (Kolmogoroff) probabilities, formally speaking, 2) these probabilities are generally interpreted as themselves conditional, and the conditions are mutually incompatible where the observables are maximal and 3) testing of the theory typically takes the form of confronting the expectation values of observable Q calculated with probability measures P(μ, Q) for states μ; hence, of comparing the probabilities P(μ, Q)(E) with the frequencies of occurrence of the corresponding events. It seems that even the interpretation of quantum mechanics, in so far as it concerns what the theory says about the empirical (i.e. actual, observable) phenomena, deals with the confrontation of classical probability measures with observable frequencies. This confrontation is studied. (Auth./C.F.)

  18. Explaining regional disparities in traffic mortality by decomposing conditional probabilities.

    Science.gov (United States)

    Goldstein, Gregory P; Clark, David E; Travis, Lori L; Haskins, Amy E

    2011-04-01

    In the USA, the mortality rate from traffic injury is higher in rural and in southern regions, for reasons that are not well understood. For 1754 (56%) of the 3142 US counties, we obtained data allowing for separation of the deaths/population rate into deaths/injury, injuries/crash, crashes/exposure and exposure/population, with exposure measured as vehicle miles travelled. A 'decomposition method' proposed by Li and Baker was extended to study how the contributions of these components were affected by three measures of rural location, as well as southern location. The method of Li and Baker extended without difficulty to include non-binary effects and multiple exposures. Deaths/injury was by far the most important determinant in the county-to-county variation in deaths/population, and accounted for the greatest portion of the rural/urban disparity. After controlling for the rural effect, injuries/crash accounted for most of the southern/northern disparity. The increased mortality rate from traffic injury in rural areas can be attributed to the increased probability of death given that a person has been injured, possibly due to challenges faced by emergency medical response systems. In southern areas, there is an increased probability of injury given that a person has crashed, possibly due to differences in vehicle, road, or driving conditions.

  19. Thermal and mechanical quantitative sensory testing in Chinese patients with burning mouth syndrome--a probable neuropathic pain condition?

    Science.gov (United States)

    Mo, Xueyin; Zhang, Jinglu; Fan, Yuan; Svensson, Peter; Wang, Kelun

    2015-01-01

    To explore the hypothesis that burning mouth syndrome (BMS) probably is a neuropathic pain condition, thermal and mechanical sensory and pain thresholds were tested and compared with age- and gender-matched control participants using a standardized battery of psychophysical techniques. Twenty-five BMS patients (men: 8, women: 17, age: 49.5 ± 11.4 years) and 19 age- and gender-matched healthy control participants were included. The cold detection threshold (CDT), warm detection threshold (WDT), cold pain threshold (CPT), heat pain threshold (HPT), mechanical detection threshold (MDT) and mechanical pain threshold (MPT), in accordance with the German Network of Neuropathic Pain guidelines, were measured at the following four sites: the dorsum of the left hand (hand), the skin at the mental foramen (chin), on the tip of the tongue (tongue), and the mucosa of the lower lip (lip). Statistical analysis was performed using ANOVA with repeated measures to compare the means within and between groups. Furthermore, Z-score profiles were generated, and exploratory correlation analyses between QST and clinical variables were performed. Two-tailed tests with a significance level of 5 % were used throughout. CDTs (P < 0.02) were significantly lower (less sensitivity) and HPTs (P < 0.001) were significantly higher (less sensitivity) at the tongue and lip in BMS patients compared to control participants. WDT (P = 0.007) was also significantly higher at the tongue in BMS patients compared to control subjects . There were no significant differences in MDT and MPT between the BMS patients and healthy subjects at any of the four test sites. Z-scores showed that significant loss of function can be identified for CDT (Z-scores = -0.9±1.1) and HPT (Z-scores = 1.5±0.4). There were no significant correlations between QST and clinical variables (pain intensity, duration, depressions scores). BMS patients had a significant loss of thermal function but not

  20. Linear positivity and virtual probability

    International Nuclear Information System (INIS)

    Hartle, James B.

    2004-01-01

    We investigate the quantum theory of closed systems based on the linear positivity decoherence condition of Goldstein and Page. The objective of any quantum theory of a closed system, most generally the universe, is the prediction of probabilities for the individual members of sets of alternative coarse-grained histories of the system. Quantum interference between members of a set of alternative histories is an obstacle to assigning probabilities that are consistent with the rules of probability theory. A quantum theory of closed systems therefore requires two elements: (1) a condition specifying which sets of histories may be assigned probabilities and (2) a rule for those probabilities. The linear positivity condition of Goldstein and Page is the weakest of the general conditions proposed so far. Its general properties relating to exact probability sum rules, time neutrality, and conservation laws are explored. Its inconsistency with the usual notion of independent subsystems in quantum mechanics is reviewed. Its relation to the stronger condition of medium decoherence necessary for classicality is discussed. The linear positivity of histories in a number of simple model systems is investigated with the aim of exhibiting linearly positive sets of histories that are not decoherent. The utility of extending the notion of probability to include values outside the range of 0-1 is described. Alternatives with such virtual probabilities cannot be measured or recorded, but can be used in the intermediate steps of calculations of real probabilities. Extended probabilities give a simple and general way of formulating quantum theory. The various decoherence conditions are compared in terms of their utility for characterizing classicality and the role they might play in further generalizations of quantum mechanics

  1. Interactive effects of senescence and natural disturbance on the annual survival probabilities of snail kites

    Science.gov (United States)

    Reichert, Brian E.; Martin, J.; Kendall, William L.; Cattau, Christopher E.; Kitchens, Wiley M.

    2010-01-01

    Individuals in wild populations face risks associated with both intrinsic (i.e. aging) and external (i.e. environmental) sources of mortality. Condition-dependent mortality occurs when there is an interaction between such factors; however, few studies have clearly demonstrated condition-dependent mortality and some have even argued that condition-dependent mortality does not occur in wild avian populations. Using large sample sizes (2084 individuals, 3746 re-sights) of individual-based longitudinal data collected over a 33 year period (1976-2008) on multiple cohorts, we used a capture-mark-recapture framework to model age-dependent survival in the snail kite Rostrhamus sociabilis plumbeus population in Florida. Adding to the growing amount of evidence for actuarial senescence in wild populations, we found evidence of senescent declines in survival probabilities in adult kites. We also tested the hypothesis that older kites experienced condition-dependent mortality during a range-wide drought event (2000-2002). The results provide convincing evidence that the annual survival probability of senescent kites was disproportionately affected by the drought relative to the survival probability of prime-aged adults. To our knowledge, this is the first evidence of condition-dependent mortality to be demonstrated in a wild avian population, a finding which challenges recent conclusions drawn in the literature. Our study suggests that senescence and condition-dependent mortality can affect the demography of wild avian populations. Accounting for these sources of variation may be particularly important to appropriately compute estimates of population growth rate, and probabilities of quasi-extinctions.

  2. Estimation of the age-specific per-contact probability of Ebola virus transmission in Liberia using agent-based simulations

    Science.gov (United States)

    Siettos, Constantinos I.; Anastassopoulou, Cleo; Russo, Lucia; Grigoras, Christos; Mylonakis, Eleftherios

    2016-06-01

    Based on multiscale agent-based computations we estimated the per-contact probability of transmission by age of the Ebola virus disease (EVD) that swept through Liberia from May 2014 to March 2015. For the approximation of the epidemic dynamics we have developed a detailed agent-based model with small-world interactions between individuals categorized by age. For the estimation of the structure of the evolving contact network as well as the per-contact transmission probabilities by age group we exploited the so called Equation-Free framework. Model parameters were fitted to official case counts reported by the World Health Organization (WHO) as well as to recently published data of key epidemiological variables, such as the mean time to death, recovery and the case fatality rate.

  3. A Comparison of Urge Intensity and the Probability of Tic Completion During Tic Freely and Tic Suppression Conditions.

    Science.gov (United States)

    Specht, Matt W; Nicotra, Cassandra M; Kelly, Laura M; Woods, Douglas W; Ricketts, Emily J; Perry-Parrish, Carisa; Reynolds, Elizabeth; Hankinson, Jessica; Grados, Marco A; Ostrander, Rick S; Walkup, John T

    2014-03-01

    Tic-suppression-based treatments (TSBTs) represent a safe and effective treatment option for Chronic Tic Disorders (CTDs). Prior research has demonstrated that treatment naive youths with CTDs have the capacity to safely and effectively suppress tics for prolonged periods. It remains unclear how tic suppression is achieved. The current study principally examines how effective suppression is achieved and preliminary correlates of the ability to suppress tics. Twelve youths, ages 10 to 17 years, with moderate-to-marked CTDs participated in an alternating sequence of tic freely and reinforced tic suppression conditions during which urge intensity and tic frequency were frequently assessed. Probability of tics occurring was half as likely following high-intensity urges during tic suppression (31%) in contrast to low-intensity urges during tic freely conditions (60%). Age was not associated with ability to suppress. Intelligence indices were associated with or trended toward greater ability to suppress tics. Attention difficulties were not associated with ability to suppress but were associated with tic severity. In contrast to our "selective suppression" hypothesis, we found participants equally capable of suppressing their tics regardless of urge intensity during reinforced tic suppression. Tic suppression was achieved with an "across-the-board" effort to resist urges. Preliminary data suggest that ability to suppress may be associated with general cognitive variables rather than age, tic severity, urge severity, and attention. Treatment naive youths appear to possess a capacity for robust tic suppression. TSBTs may bolster these capacities and/or enable their broader implementation, resulting in symptom improvement. © The Author(s) 2014.

  4. Bayesian probability analysis: a prospective demonstration of its clinical utility in diagnosing coronary disease

    International Nuclear Information System (INIS)

    Detrano, R.; Yiannikas, J.; Salcedo, E.E.; Rincon, G.; Go, R.T.; Williams, G.; Leatherman, J.

    1984-01-01

    One hundred fifty-four patients referred for coronary arteriography were prospectively studied with stress electrocardiography, stress thallium scintigraphy, cine fluoroscopy (for coronary calcifications), and coronary angiography. Pretest probabilities of coronary disease were determined based on age, sex, and type of chest pain. These and pooled literature values for the conditional probabilities of test results based on disease state were used in Bayes theorem to calculate posttest probabilities of disease. The results of the three noninvasive tests were compared for statistical independence, a necessary condition for their simultaneous use in Bayes theorem. The test results were found to demonstrate pairwise independence in patients with and those without disease. Some dependencies that were observed between the test results and the clinical variables of age and sex were not sufficient to invalidate application of the theorem. Sixty-eight of the study patients had at least one major coronary artery obstruction of greater than 50%. When these patients were divided into low-, intermediate-, and high-probability subgroups according to their pretest probabilities, noninvasive test results analyzed by Bayesian probability analysis appropriately advanced 17 of them by at least one probability subgroup while only seven were moved backward. Of the 76 patients without disease, 34 were appropriately moved into a lower probability subgroup while 10 were incorrectly moved up. We conclude that posttest probabilities calculated from Bayes theorem more accurately classified patients with and without disease than did pretest probabilities, thus demonstrating the utility of the theorem in this application

  5. Probability and stochastic modeling

    CERN Document Server

    Rotar, Vladimir I

    2012-01-01

    Basic NotionsSample Space and EventsProbabilitiesCounting TechniquesIndependence and Conditional ProbabilityIndependenceConditioningThe Borel-Cantelli TheoremDiscrete Random VariablesRandom Variables and VectorsExpected ValueVariance and Other Moments. Inequalities for DeviationsSome Basic DistributionsConvergence of Random Variables. The Law of Large NumbersConditional ExpectationGenerating Functions. Branching Processes. Random Walk RevisitedBranching Processes Generating Functions Branching Processes Revisited More on Random WalkMarkov ChainsDefinitions and Examples. Probability Distributions of Markov ChainsThe First Step Analysis. Passage TimesVariables Defined on a Markov ChainErgodicity and Stationary DistributionsA Classification of States and ErgodicityContinuous Random VariablesContinuous DistributionsSome Basic Distributions Continuous Multivariate Distributions Sums of Independent Random Variables Conditional Distributions and ExpectationsDistributions in the General Case. SimulationDistribution F...

  6. Genetic evaluation of weaning weight and probability of lambing at 1 year of age in Targhee lambs

    Science.gov (United States)

    The objective of this study was to investigate genetic control of 120-day weaning weight and the probability of lambing at 1 year of age in Targhee ewe lambs. Records of 5,967 ewe lambs born from 1989 to 2012 and first exposed to rams for breeding at approximately 7 months of age were analyzed. Reco...

  7. Age dynamic of physical condition changes in pre-school age girls, schoolgirls and students, living in conditions of Eastern Siberia

    Directory of Open Access Journals (Sweden)

    V.Y. Lebedinskiy

    2017-12-01

    Full Text Available Purpose: to analyze dynamic of physical condition, considering sex (females and age of the tested, living in region with unfavorable ecology. Material: we studied pre school age girls (n=1580, age 4-7 years. In the research we did not include children with chronic diseases, who were under observation. We tested schoolgirls (n=3211, age 7-17 years and girl students (n=5827, age 17-21 years, 1-4 years of study. Girl students were divided into five age groups: from 17 to 21 years. All participants lived in conditions of Eastern Siberia (Irkutsk. This region is characterized by unfavorable ecology and climate geographic characteristics. Results: in dynamic of physical condition of pre-school girls, schoolgirls and students we marked out three substantial periods of it characteristics' changes. Age 7-8 years is critical (transition from 1st to 2nd stage. The least values of these characteristics are found in older (after 17-18 years ages. In students we observed relative stabilization of these indicators. Conclusions: the received results shall be considered in building physical education training process in pre-school educational establishments, secondary comprehensive schools and higher educational establishments.

  8. Probability distribution of magnetization in the one-dimensional Ising model: effects of boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Antal, T [Physics Department, Simon Fraser University, Burnaby, BC V5A 1S6 (Canada); Droz, M [Departement de Physique Theorique, Universite de Geneve, CH 1211 Geneva 4 (Switzerland); Racz, Z [Institute for Theoretical Physics, Eoetvoes University, 1117 Budapest, Pazmany setany 1/a (Hungary)

    2004-02-06

    Finite-size scaling functions are investigated both for the mean-square magnetization fluctuations and for the probability distribution of the magnetization in the one-dimensional Ising model. The scaling functions are evaluated in the limit of the temperature going to zero (T {yields} 0), the size of the system going to infinity (N {yields} {infinity}) while N[1 - tanh(J/k{sub B}T)] is kept finite (J being the nearest neighbour coupling). Exact calculations using various boundary conditions (periodic, antiperiodic, free, block) demonstrate explicitly how the scaling functions depend on the boundary conditions. We also show that the block (small part of a large system) magnetization distribution results are identical to those obtained for free boundary conditions.

  9. Probabilistic Approach to Conditional Probability of Release of Hazardous Materials from Railroad Tank Cars during Accidents

    Science.gov (United States)

    2009-10-13

    This paper describes a probabilistic approach to estimate the conditional probability of release of hazardous materials from railroad tank cars during train accidents. Monte Carlo methods are used in developing a probabilistic model to simulate head ...

  10. Impact of Age on the Risk of Advanced Colorectal Neoplasia in a Young Population: An Analysis Using the Predicted Probability Model.

    Science.gov (United States)

    Jung, Yoon Suk; Park, Chan Hyuk; Kim, Nam Hee; Lee, Mi Yeon; Park, Dong Il

    2017-09-01

    The incidence of colorectal cancer is decreasing in adults aged ≥50 years and increasing in those aged probability models for ACRN in a population aged 30-49 years. Of 96,235 participants, 57,635 and 38,600 were included in the derivation and validation cohorts, respectively. The predicted probability model considered age, sex, body mass index, family history of colorectal cancer, and smoking habits, as follows: Y ACRN  = -8.755 + 0.080·X age  - 0.055·X male  + 0.041·X BMI  + 0.200·X family_history_of_CRC  + 0.218·X former_smoker  + 0.644·X current_smoker . The optimal cutoff value for the predicted probability of ACRN by Youden index was 1.14%. The area under the receiver-operating characteristic curve (AUROC) values of our model for ACRN were higher than those of the previously established Asia-Pacific Colorectal Screening (APCS), Korean Colorectal Screening (KCS), and Kaminski's scoring models [AUROC (95% confidence interval): model in the current study, 0.673 (0.648-0.697); vs. APCS, 0.588 (0.564-0.611), P probability model can assess the risk of ACRN more accurately than existing models, including the APCS, KCS, and Kaminski's scoring models.

  11. Calculating the Probability of Returning a Loan with Binary Probability Models

    Directory of Open Access Journals (Sweden)

    Julian Vasilev

    2014-12-01

    Full Text Available The purpose of this article is to give a new approach in calculating the probability of returning a loan. A lot of factors affect the value of the probability. In this article by using statistical and econometric models some influencing factors are proved. The main approach is concerned with applying probit and logit models in loan management institutions. A new aspect of the credit risk analysis is given. Calculating the probability of returning a loan is a difficult task. We assume that specific data fields concerning the contract (month of signing, year of signing, given sum and data fields concerning the borrower of the loan (month of birth, year of birth (age, gender, region, where he/she lives may be independent variables in a binary logistics model with a dependent variable “the probability of returning a loan”. It is proved that the month of signing a contract, the year of signing a contract, the gender and the age of the loan owner do not affect the probability of returning a loan. It is proved that the probability of returning a loan depends on the sum of contract, the remoteness of the loan owner and the month of birth. The probability of returning a loan increases with the increase of the given sum, decreases with the proximity of the customer, increases for people born in the beginning of the year and decreases for people born at the end of the year.

  12. Probability of detecting perchlorate under natural conditions in deep groundwater in California and the Southwestern United States

    Science.gov (United States)

    Fram, Miranda S.; Belitz, Kenneth

    2011-01-01

    We use data from 1626 groundwater samples collected in California, primarily from public drinking water supply wells, to investigate the distribution of perchlorate in deep groundwater under natural conditions. The wells were sampled for the California Groundwater Ambient Monitoring and Assessment Priority Basin Project. We develop a logistic regression model for predicting probabilities of detecting perchlorate at concentrations greater than multiple threshold concentrations as a function of climate (represented by an aridity index) and potential anthropogenic contributions of perchlorate (quantified as an anthropogenic score, AS). AS is a composite categorical variable including terms for nitrate, pesticides, and volatile organic compounds. Incorporating water-quality parameters in AS permits identification of perturbation of natural occurrence patterns by flushing of natural perchlorate salts from unsaturated zones by irrigation recharge as well as addition of perchlorate from industrial and agricultural sources. The data and model results indicate low concentrations (0.1-0.5 μg/L) of perchlorate occur under natural conditions in groundwater across a wide range of climates, beyond the arid to semiarid climates in which they mostly have been previously reported. The probability of detecting perchlorate at concentrations greater than 0.1 μg/L under natural conditions ranges from 50-70% in semiarid to arid regions of California and the Southwestern United States to 5-15% in the wettest regions sampled (the Northern California coast). The probability of concentrations above 1 μg/L under natural conditions is low (generally <3%).

  13. Gender and Ageing at Work in Chile: Employment, Working Conditions, Work-Life Balance and Health of Men and Women in an Ageing Workforce.

    Science.gov (United States)

    Vives, Alejandra; Gray, Nora; González, Francisca; Molina, Agustín

    2018-04-18

    workplace risks continue to be high into old age: intensive work and demanding physical work, especially in men, and the combination of paid and unpaid care work in women, which continues to be high up to the age of 70 years. The health of older workers is better than that of non-working people of the same age, a gap which is markedly larger for women than men and tends to increase among women as they age. Results indicate that Chileans working into old age face precarious jobs with limited protection and several adverse working conditions. Noteworthy, women carry the double burden of paid and unpaid work into their late years. In addition, results suggest they are affected more profoundly by the healthy worker effect whereby the health condition determines the probability of finding and keeping a job-also known as a health selection mechanism-which increases as they age. These employment and working conditions indicate that working into old age is not yet sustainable in Chile and counts as evidence that needs to be taken into account in discussions about delaying the retirement age in the country, as well as incorporating support systems to alleviate the double work burden of ageing working women.

  14. Conditional probability distribution associated to the E-M image reconstruction algorithm for neutron stimulated emission tomography

    International Nuclear Information System (INIS)

    Viana, R.S.; Yoriyaz, H.; Santos, A.

    2011-01-01

    The Expectation-Maximization (E-M) algorithm is an iterative computational method for maximum likelihood (M-L) estimates, useful in a variety of incomplete-data problems. Due to its stochastic nature, one of the most relevant applications of E-M algorithm is the reconstruction of emission tomography images. In this paper, the statistical formulation of the E-M algorithm was applied to the in vivo spectrographic imaging of stable isotopes called Neutron Stimulated Emission Computed Tomography (NSECT). In the process of E-M algorithm iteration, the conditional probability distribution plays a very important role to achieve high quality image. This present work proposes an alternative methodology for the generation of the conditional probability distribution associated to the E-M reconstruction algorithm, using the Monte Carlo code MCNP5 and with the application of the reciprocity theorem. (author)

  15. Conditional probability distribution associated to the E-M image reconstruction algorithm for neutron stimulated emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Viana, R.S.; Yoriyaz, H.; Santos, A., E-mail: rodrigossviana@gmail.com, E-mail: hyoriyaz@ipen.br, E-mail: asantos@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    The Expectation-Maximization (E-M) algorithm is an iterative computational method for maximum likelihood (M-L) estimates, useful in a variety of incomplete-data problems. Due to its stochastic nature, one of the most relevant applications of E-M algorithm is the reconstruction of emission tomography images. In this paper, the statistical formulation of the E-M algorithm was applied to the in vivo spectrographic imaging of stable isotopes called Neutron Stimulated Emission Computed Tomography (NSECT). In the process of E-M algorithm iteration, the conditional probability distribution plays a very important role to achieve high quality image. This present work proposes an alternative methodology for the generation of the conditional probability distribution associated to the E-M reconstruction algorithm, using the Monte Carlo code MCNP5 and with the application of the reciprocity theorem. (author)

  16. Determination of the failure probability in the weld region of ap-600 vessel for transient condition

    International Nuclear Information System (INIS)

    Wahyono, I.P.

    1997-01-01

    Failure probability in the weld region of AP-600 vessel was determined for transient condition scenario. The type of transient is increase of the heat removal from primary cooling system due to sudden opening of safety valves or steam relief valves on the secondary cooling system or the steam generator. Temperature and pressure in the vessel was considered as the base of deterministic calculation of the stress intensity factor. Calculation of film coefficient of the convective heat transfers is a function of the transient time and water parameter. Pressure, material temperature, flaw depth and transient time are variables for the stress intensity factor. Failure probability consideration was done by using the above information in regard with the flaw and probability distributions of Octavia II and Marshall. Calculation of the failure probability by probability fracture mechanic simulation is applied on the weld region. Failure of the vessel is assumed as a failure of the weld material with one crack which stress intensity factor applied is higher than the critical stress intensity factor. VISA II code (Vessel Integrity Simulation Analysis II) was used for deterministic calculation and simulation. Failure probability of the material is 1.E-5 for Octavia II distribution and 4E-6 for marshall distribution for each transient event postulated. The failure occurred at the 1.7th menit of the initial transient under 12.53 ksi of the pressure

  17. Introduction to probability with Mathematica

    CERN Document Server

    Hastings, Kevin J

    2009-01-01

    Discrete ProbabilityThe Cast of Characters Properties of Probability Simulation Random SamplingConditional ProbabilityIndependenceDiscrete DistributionsDiscrete Random Variables, Distributions, and ExpectationsBernoulli and Binomial Random VariablesGeometric and Negative Binomial Random Variables Poisson DistributionJoint, Marginal, and Conditional Distributions More on ExpectationContinuous ProbabilityFrom the Finite to the (Very) Infinite Continuous Random Variables and DistributionsContinuous ExpectationContinuous DistributionsThe Normal Distribution Bivariate Normal DistributionNew Random Variables from OldOrder Statistics Gamma DistributionsChi-Square, Student's t, and F-DistributionsTransformations of Normal Random VariablesAsymptotic TheoryStrong and Weak Laws of Large Numbers Central Limit TheoremStochastic Processes and ApplicationsMarkov ChainsPoisson Processes QueuesBrownian MotionFinancial MathematicsAppendixIntroduction to Mathematica Glossary of Mathematica Commands for Probability Short Answers...

  18. Evidence reasoning method for constructing conditional probability tables in a Bayesian network of multimorbidity.

    Science.gov (United States)

    Du, Yuanwei; Guo, Yubin

    2015-01-01

    The intrinsic mechanism of multimorbidity is difficult to recognize and prediction and diagnosis are difficult to carry out accordingly. Bayesian networks can help to diagnose multimorbidity in health care, but it is difficult to obtain the conditional probability table (CPT) because of the lack of clinically statistical data. Today, expert knowledge and experience are increasingly used in training Bayesian networks in order to help predict or diagnose diseases, but the CPT in Bayesian networks is usually irrational or ineffective for ignoring realistic constraints especially in multimorbidity. In order to solve these problems, an evidence reasoning (ER) approach is employed to extract and fuse inference data from experts using a belief distribution and recursive ER algorithm, based on which evidence reasoning method for constructing conditional probability tables in Bayesian network of multimorbidity is presented step by step. A multimorbidity numerical example is used to demonstrate the method and prove its feasibility and application. Bayesian network can be determined as long as the inference assessment is inferred by each expert according to his/her knowledge or experience. Our method is more effective than existing methods for extracting expert inference data accurately and is fused effectively for constructing CPTs in a Bayesian network of multimorbidity.

  19. Estimating the Probability of Traditional Copying, Conditional on Answer-Copying Statistics.

    Science.gov (United States)

    Allen, Jeff; Ghattas, Andrew

    2016-06-01

    Statistics for detecting copying on multiple-choice tests produce p values measuring the probability of a value at least as large as that observed, under the null hypothesis of no copying. The posterior probability of copying is arguably more relevant than the p value, but cannot be derived from Bayes' theorem unless the population probability of copying and probability distribution of the answer-copying statistic under copying are known. In this article, the authors develop an estimator for the posterior probability of copying that is based on estimable quantities and can be used with any answer-copying statistic. The performance of the estimator is evaluated via simulation, and the authors demonstrate how to apply the formula using actual data. Potential uses, generalizability to other types of cheating, and limitations of the approach are discussed.

  20. Probability matching in perceptrons: Effects of conditional dependence and linear nonseparability.

    Directory of Open Access Journals (Sweden)

    Michael R W Dawson

    Full Text Available Probability matching occurs when the behavior of an agent matches the likelihood of occurrence of events in the agent's environment. For instance, when artificial neural networks match probability, the activity in their output unit equals the past probability of reward in the presence of a stimulus. Our previous research demonstrated that simple artificial neural networks (perceptrons, which consist of a set of input units directly connected to a single output unit learn to match probability when presented different cues in isolation. The current paper extends this research by showing that perceptrons can match probabilities when presented simultaneous cues, with each cue signaling different reward likelihoods. In our first simulation, we presented up to four different cues simultaneously; the likelihood of reward signaled by the presence of one cue was independent of the likelihood of reward signaled by other cues. Perceptrons learned to match reward probabilities by treating each cue as an independent source of information about the likelihood of reward. In a second simulation, we violated the independence between cues by making some reward probabilities depend upon cue interactions. We did so by basing reward probabilities on a logical combination (AND or XOR of two of the four possible cues. We also varied the size of the reward associated with the logical combination. We discovered that this latter manipulation was a much better predictor of perceptron performance than was the logical structure of the interaction between cues. This indicates that when perceptrons learn to match probabilities, they do so by assuming that each signal of a reward is independent of any other; the best predictor of perceptron performance is a quantitative measure of the independence of these input signals, and not the logical structure of the problem being learned.

  1. Probability matching in perceptrons: Effects of conditional dependence and linear nonseparability

    Science.gov (United States)

    2017-01-01

    Probability matching occurs when the behavior of an agent matches the likelihood of occurrence of events in the agent’s environment. For instance, when artificial neural networks match probability, the activity in their output unit equals the past probability of reward in the presence of a stimulus. Our previous research demonstrated that simple artificial neural networks (perceptrons, which consist of a set of input units directly connected to a single output unit) learn to match probability when presented different cues in isolation. The current paper extends this research by showing that perceptrons can match probabilities when presented simultaneous cues, with each cue signaling different reward likelihoods. In our first simulation, we presented up to four different cues simultaneously; the likelihood of reward signaled by the presence of one cue was independent of the likelihood of reward signaled by other cues. Perceptrons learned to match reward probabilities by treating each cue as an independent source of information about the likelihood of reward. In a second simulation, we violated the independence between cues by making some reward probabilities depend upon cue interactions. We did so by basing reward probabilities on a logical combination (AND or XOR) of two of the four possible cues. We also varied the size of the reward associated with the logical combination. We discovered that this latter manipulation was a much better predictor of perceptron performance than was the logical structure of the interaction between cues. This indicates that when perceptrons learn to match probabilities, they do so by assuming that each signal of a reward is independent of any other; the best predictor of perceptron performance is a quantitative measure of the independence of these input signals, and not the logical structure of the problem being learned. PMID:28212422

  2. Probability matching in perceptrons: Effects of conditional dependence and linear nonseparability.

    Science.gov (United States)

    Dawson, Michael R W; Gupta, Maya

    2017-01-01

    Probability matching occurs when the behavior of an agent matches the likelihood of occurrence of events in the agent's environment. For instance, when artificial neural networks match probability, the activity in their output unit equals the past probability of reward in the presence of a stimulus. Our previous research demonstrated that simple artificial neural networks (perceptrons, which consist of a set of input units directly connected to a single output unit) learn to match probability when presented different cues in isolation. The current paper extends this research by showing that perceptrons can match probabilities when presented simultaneous cues, with each cue signaling different reward likelihoods. In our first simulation, we presented up to four different cues simultaneously; the likelihood of reward signaled by the presence of one cue was independent of the likelihood of reward signaled by other cues. Perceptrons learned to match reward probabilities by treating each cue as an independent source of information about the likelihood of reward. In a second simulation, we violated the independence between cues by making some reward probabilities depend upon cue interactions. We did so by basing reward probabilities on a logical combination (AND or XOR) of two of the four possible cues. We also varied the size of the reward associated with the logical combination. We discovered that this latter manipulation was a much better predictor of perceptron performance than was the logical structure of the interaction between cues. This indicates that when perceptrons learn to match probabilities, they do so by assuming that each signal of a reward is independent of any other; the best predictor of perceptron performance is a quantitative measure of the independence of these input signals, and not the logical structure of the problem being learned.

  3. Concepts and Bounded Rationality: An Application of Niestegge's Approach to Conditional Quantum Probabilities

    Science.gov (United States)

    Blutner, Reinhard

    2009-03-01

    Recently, Gerd Niestegge developed a new approach to quantum mechanics via conditional probabilities developing the well-known proposal to consider the Lüders-von Neumann measurement as a non-classical extension of probability conditionalization. I will apply his powerful and rigorous approach to the treatment of concepts using a geometrical model of meaning. In this model, instances are treated as vectors of a Hilbert space H. In the present approach there are at least two possibilities to form categories. The first possibility sees categories as a mixture of its instances (described by a density matrix). In the simplest case we get the classical probability theory including the Bayesian formula. The second possibility sees categories formed by a distinctive prototype which is the superposition of the (weighted) instances. The construction of prototypes can be seen as transferring a mixed quantum state into a pure quantum state freezing the probabilistic characteristics of the superposed instances into the structure of the formed prototype. Closely related to the idea of forming concepts by prototypes is the existence of interference effects. Such inference effects are typically found in macroscopic quantum systems and I will discuss them in connection with several puzzles of bounded rationality. The present approach nicely generalizes earlier proposals made by authors such as Diederik Aerts, Andrei Khrennikov, Ricardo Franco, and Jerome Busemeyer. Concluding, I will suggest that an active dialogue between cognitive approaches to logic and semantics and the modern approach of quantum information science is mandatory.

  4. Probability in physics

    CERN Document Server

    Hemmo, Meir

    2012-01-01

    What is the role and meaning of probability in physical theory, in particular in two of the most successful theories of our age, quantum physics and statistical mechanics? Laws once conceived as universal and deterministic, such as Newton‘s laws of motion, or the second law of thermodynamics, are replaced in these theories by inherently probabilistic laws. This collection of essays by some of the world‘s foremost experts presents an in-depth analysis of the meaning of probability in contemporary physics. Among the questions addressed are: How are probabilities defined? Are they objective or subjective? What is their  explanatory value? What are the differences between quantum and classical probabilities? The result is an informative and thought-provoking book for the scientifically inquisitive. 

  5. Dynamic Forecasting Conditional Probability of Bombing Attacks Based on Time-Series and Intervention Analysis.

    Science.gov (United States)

    Li, Shuying; Zhuang, Jun; Shen, Shifei

    2017-07-01

    In recent years, various types of terrorist attacks occurred, causing worldwide catastrophes. According to the Global Terrorism Database (GTD), among all attack tactics, bombing attacks happened most frequently, followed by armed assaults. In this article, a model for analyzing and forecasting the conditional probability of bombing attacks (CPBAs) based on time-series methods is developed. In addition, intervention analysis is used to analyze the sudden increase in the time-series process. The results show that the CPBA increased dramatically at the end of 2011. During that time, the CPBA increased by 16.0% in a two-month period to reach the peak value, but still stays 9.0% greater than the predicted level after the temporary effect gradually decays. By contrast, no significant fluctuation can be found in the conditional probability process of armed assault. It can be inferred that some social unrest, such as America's troop withdrawal from Afghanistan and Iraq, could have led to the increase of the CPBA in Afghanistan, Iraq, and Pakistan. The integrated time-series and intervention model is used to forecast the monthly CPBA in 2014 and through 2064. The average relative error compared with the real data in 2014 is 3.5%. The model is also applied to the total number of attacks recorded by the GTD between 2004 and 2014. © 2016 Society for Risk Analysis.

  6. Real analysis and probability

    CERN Document Server

    Ash, Robert B; Lukacs, E

    1972-01-01

    Real Analysis and Probability provides the background in real analysis needed for the study of probability. Topics covered range from measure and integration theory to functional analysis and basic concepts of probability. The interplay between measure theory and topology is also discussed, along with conditional probability and expectation, the central limit theorem, and strong laws of large numbers with respect to martingale theory.Comprised of eight chapters, this volume begins with an overview of the basic concepts of the theory of measure and integration, followed by a presentation of var

  7. Logic, probability, and human reasoning.

    Science.gov (United States)

    Johnson-Laird, P N; Khemlani, Sangeet S; Goodwin, Geoffrey P

    2015-04-01

    This review addresses the long-standing puzzle of how logic and probability fit together in human reasoning. Many cognitive scientists argue that conventional logic cannot underlie deductions, because it never requires valid conclusions to be withdrawn - not even if they are false; it treats conditional assertions implausibly; and it yields many vapid, although valid, conclusions. A new paradigm of probability logic allows conclusions to be withdrawn and treats conditionals more plausibly, although it does not address the problem of vapidity. The theory of mental models solves all of these problems. It explains how people reason about probabilities and postulates that the machinery for reasoning is itself probabilistic. Recent investigations accordingly suggest a way to integrate probability and deduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Working conditions in mid-life and mental health in older ages.

    Science.gov (United States)

    Wahrendorf, Morten; Blane, David; Bartley, Mel; Dragano, Nico; Siegrist, Johannes

    2013-03-01

    This article illustrates the importance of previous working conditions during mid-life (between 40 and 55) for mental health among older retired men and women (60 or older) across 13 European countries. We link information on health from the second wave (2006-2007) of the Survey of Health, Ageing and Retirement in Europe (SHARE) with information on respondents' working life collected retrospectively in the SHARELIFE interview (2008-2009). To measure working conditions, we rely on core assumptions of existing theoretical models of work stress (the demand-control-support and the effort-reward imbalance model) and distinguish four types of unhealthy working conditions: (1) a stressful psychosocial work environment (as assessed by the two work stress models) (2) a disadvantaged occupational position throughout the whole period of mid-life, (3) experience of involuntary job loss, and (4) exposure to job instability. Health after labour market exit is measured using depressive symptoms, as measured by the EURO-D depression scale. Main results show that men and women who experienced psychosocial stress at work or had low occupational positions during mid-life had significantly higher probabilities of high depressive symptoms during retirement. Additionally, men with unstable working careers and an involuntary job loss were at higher risks to report high depressive symptoms in later life. These associations remain significant after controlling for workers' health and social position prior mid-life. These findings support the assumption that mental health of retirees who experienced poor working conditions during mid-life is impaired. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Accelerated aging of AP/HTPB propellants and the influence of various environmental aging conditions

    NARCIS (Netherlands)

    Keizers, H.L.J.

    1995-01-01

    Preliminary resuits on accelerated aging of lab-scale produced AP/HTPB propellant and propellants from dissectioned rocket motors are discussed, including aging logic, storage conditions, test techniques and resuits on mechanical, ballistic and safety testing. The mam aging effect observed was

  10. Prediction suppression in monkey inferotemporal cortex depends on the conditional probability between images.

    Science.gov (United States)

    Ramachandran, Suchitra; Meyer, Travis; Olson, Carl R

    2016-01-01

    When monkeys view two images in fixed sequence repeatedly over days and weeks, neurons in area TE of the inferotemporal cortex come to exhibit prediction suppression. The trailing image elicits only a weak response when presented following the leading image that preceded it during training. Induction of prediction suppression might depend either on the contiguity of the images, as determined by their co-occurrence and captured in the measure of joint probability P(A,B), or on their contingency, as determined by their correlation and as captured in the measures of conditional probability P(A|B) and P(B|A). To distinguish between these possibilities, we measured prediction suppression after imposing training regimens that held P(A,B) constant but varied P(A|B) and P(B|A). We found that reducing either P(A|B) or P(B|A) during training attenuated prediction suppression as measured during subsequent testing. We conclude that prediction suppression depends on contingency, as embodied in the predictive relations between the images, and not just on contiguity, as embodied in their co-occurrence. Copyright © 2016 the American Physiological Society.

  11. Probability of an Abnormal Screening PSA Result Based on Age, Race, and PSA Threshold

    Science.gov (United States)

    Espaldon, Roxanne; Kirby, Katharine A.; Fung, Kathy Z.; Hoffman, Richard M.; Powell, Adam A.; Freedland, Stephen J.; Walter, Louise C.

    2014-01-01

    Objective To determine the distribution of screening PSA values in older men and how different PSA thresholds affect the proportion of white, black, and Latino men who would have an abnormal screening result across advancing age groups. Methods We used linked national VA and Medicare data to determine the value of the first screening PSA test (ng/mL) of 327,284 men age 65+ who underwent PSA screening in the VA healthcare system in 2003. We calculated the proportion of men with an abnormal PSA result based on age, race, and common PSA thresholds. Results Among men age 65+, 8.4% had a PSA >4.0ng/mL. The percentage of men with a PSA >4.0ng/mL increased with age and was highest in black men (13.8%) versus white (8.0%) or Latino men (10.0%) (PPSA >4.0ng/mL ranged from 5.1% of Latino men age 65–69 to 27.4% of black men age 85+. Raising the PSA threshold from >4.0ng/mL to >10.0ng/mL, reclassified the greatest percentage of black men age 85+ (18.3% absolute change) and the lowest percentage of Latino men age 65–69 (4.8% absolute change) as being under the biopsy threshold (PPSA threshold together affect the pre-test probability of an abnormal screening PSA result. Based on screening PSA distributions, stopping screening among men whose PSA 10ng/ml has the greatest effect on reducing the number of older black men who will face biopsy decisions after screening. PMID:24439009

  12. Schema bias in source monitoring varies with encoding conditions: support for a probability-matching account.

    Science.gov (United States)

    Kuhlmann, Beatrice G; Vaterrodt, Bianca; Bayen, Ute J

    2012-09-01

    Two experiments examined reliance on schematic knowledge in source monitoring. Based on a probability-matching account of source guessing, a schema bias will only emerge if participants do not have a representation of the source-item contingency in the study list, or if the perceived contingency is consistent with schematic expectations. Thus, the account predicts that encoding conditions that affect contingency detection also affect schema bias. In Experiment 1, the schema bias commonly found when schematic information about the sources is not provided before encoding was diminished by an intentional source-memory instruction. In Experiment 2, the depth of processing of schema-consistent and schema-inconsistent source-item pairings was manipulated. Participants consequently overestimated the occurrence of the pairing type they processed in a deep manner, and their source guessing reflected this biased contingency perception. Results support the probability-matching account of source guessing. PsycINFO Database Record (c) 2012 APA, all rights reserved.

  13. The Importance of Conditional Probability in Diagnostic Reasoning and Clinical Decision Making: A Primer for the Eye Care Practitioner.

    Science.gov (United States)

    Sanfilippo, Paul G; Hewitt, Alex W; Mackey, David A

    2017-04-01

    To outline and detail the importance of conditional probability in clinical decision making and discuss the various diagnostic measures eye care practitioners should be aware of in order to improve the scope of their clinical practice. We conducted a review of the importance of conditional probability in diagnostic testing for the eye care practitioner. Eye care practitioners use diagnostic tests on a daily basis to assist in clinical decision making and optimizing patient care and management. These tests provide probabilistic information that can enable the clinician to increase (or decrease) their level of certainty about the presence of a particular condition. While an understanding of the characteristics of diagnostic tests are essential to facilitate proper interpretation of test results and disease risk, many practitioners either confuse or misinterpret these measures. In the interests of their patients, practitioners should be aware of the basic concepts associated with diagnostic testing and the simple mathematical rule that underpins them. Importantly, the practitioner needs to recognize that the prevalence of a disease in the population greatly determines the clinical value of a diagnostic test.

  14. Conditional non-independence of radiographic image features and the derivation of post-test probabilities – A mammography BI-RADS example

    International Nuclear Information System (INIS)

    Benndorf, Matthias

    2012-01-01

    Bayes' theorem has proven to be one of the cornerstones in medical decision making. It allows for the derivation of post-test probabilities, which in case of a positive test result become positive predictive values. If several test results are observed successively Bayes' theorem may be used with assumed conditional independence of test results or with incorporated conditional dependencies. Herein it is examined whether radiographic image features should be considered conditionally independent diagnostic tests when post-test probabilities are to be derived. For this purpose the mammographic mass dataset from the UCI (University of California, Irvine) machine learning repository is analysed. It comprises the description of 961 (516 benign, 445 malignant) mammographic mass lesions according to the BI-RADS (Breast Imaging: Reporting and Data System) lexicon. Firstly, an exhaustive correlation matrix is presented for mammography BI-RADS features among benign and malignant lesions separately; correlation can be regarded as measure for conditional dependence. Secondly, it is shown that the derived positive predictive values for the conjunction of the two features “irregular shape” and “spiculated margin” differ significantly depending on whether conditional dependencies are incorporated into the decision process or not. It is concluded that radiographic image features should not generally be regarded as conditionally independent diagnostic tests.

  15. Pre-Service Teachers' Conceptions of Probability

    Science.gov (United States)

    Odafe, Victor U.

    2011-01-01

    Probability knowledge and skills are needed in science and in making daily decisions that are sometimes made under uncertain conditions. Hence, there is the need to ensure that the pre-service teachers of our children are well prepared to teach probability. Pre-service teachers' conceptions of probability are identified, and ways of helping them…

  16. Rainfall and net infiltration probabilities for future climate conditions at Yucca Mountain

    International Nuclear Information System (INIS)

    Long, A.; Childs, S.W.

    1993-01-01

    Performance assessment of repository integrity is a task rendered difficult because it requires predicting the future. This challenge has occupied many scientists who realize that the best assessments are required to maximize the probability of successful repository sitting and design. As part of a performance assessment effort directed by the EPRI, the authors have used probabilistic methods to assess the magnitude and timing of net infiltration at Yucca Mountain. A mathematical model for net infiltration previously published incorporated a probabilistic treatment of climate, surface hydrologic processes and a mathematical model of the infiltration process. In this paper, we present the details of the climatological analysis. The precipitation model is event-based, simulating characteristics of modern rainfall near Yucca Mountain, then extending the model to most likely values for different degrees of pluvial climates. Next the precipitation event model is fed into a process-based infiltration model that considers spatial variability in parameters relevant to net infiltration of Yucca Mountain. The model predicts that average annual net infiltration at Yucca Mountain will range from a mean of about 1 mm under present climatic conditions to a mean of at least 2.4 mm under full glacial (pluvial) conditions. Considerable variations about these means are expected to occur from year-to-year

  17. Risk estimation using probability machines

    Science.gov (United States)

    2014-01-01

    Background Logistic regression has been the de facto, and often the only, model used in the description and analysis of relationships between a binary outcome and observed features. It is widely used to obtain the conditional probabilities of the outcome given predictors, as well as predictor effect size estimates using conditional odds ratios. Results We show how statistical learning machines for binary outcomes, provably consistent for the nonparametric regression problem, can be used to provide both consistent conditional probability estimation and conditional effect size estimates. Effect size estimates from learning machines leverage our understanding of counterfactual arguments central to the interpretation of such estimates. We show that, if the data generating model is logistic, we can recover accurate probability predictions and effect size estimates with nearly the same efficiency as a correct logistic model, both for main effects and interactions. We also propose a method using learning machines to scan for possible interaction effects quickly and efficiently. Simulations using random forest probability machines are presented. Conclusions The models we propose make no assumptions about the data structure, and capture the patterns in the data by just specifying the predictors involved and not any particular model structure. So they do not run the same risks of model mis-specification and the resultant estimation biases as a logistic model. This methodology, which we call a “risk machine”, will share properties from the statistical machine that it is derived from. PMID:24581306

  18. Evaluation of cable aging degradation based on plant operating condition

    International Nuclear Information System (INIS)

    Kim, Jong-Seog

    2005-01-01

    Extending the lifetime of nuclear power plant [(hereafter referred simply as ''NPP'')] is one of the most important concerns in the world nuclear industry. Cables are one of the long live items which have not been considered to be replaced during the design life of NPP. To extend the cable life beyond the design life, we need to prove that the design life is too conservative compared with the actual aging. Condition monitoring is one of the useful ways for evaluating the aging condition of cable. In order to simulate the natural aging in nuclear power plant, a study on accelerated aging needs to be conducted first. In this paper, evaluations of mechanical aging degradation for cable jacket were performed after accelerated aging under the continuous heating and intermittent heating. Contrary to general expectation, the intermittent heating to cable jacket showed low aging degradation, 50% break-elongation and 60% indenter modulus, compared with continuous heating. With the plant maintenance period of 1 month after every 12 or 18 months operation, we can easily deduce that the life time of cable jacket can be extended much longer than estimated through the general EQ (Environmental Qualification) test, which adopts continuous accelerated aging for determining cable life. Therefore, a systematic approach which considers the actual environment condition of nuclear power plant is required for determining the life of cables. (author)

  19. Solving probability reasoning based on DNA strand displacement and probability modules.

    Science.gov (United States)

    Zhang, Qiang; Wang, Xiaobiao; Wang, Xiaojun; Zhou, Changjun

    2017-12-01

    In computation biology, DNA strand displacement technology is used to simulate the computation process and has shown strong computing ability. Most researchers use it to solve logic problems, but it is only rarely used in probabilistic reasoning. To process probabilistic reasoning, a conditional probability derivation model and total probability model based on DNA strand displacement were established in this paper. The models were assessed through the game "read your mind." It has been shown to enable the application of probabilistic reasoning in genetic diagnosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Probability theory and mathematical statistics for engineers

    CERN Document Server

    Pugachev, V S

    1984-01-01

    Probability Theory and Mathematical Statistics for Engineers focuses on the concepts of probability theory and mathematical statistics for finite-dimensional random variables.The publication first underscores the probabilities of events, random variables, and numerical characteristics of random variables. Discussions focus on canonical expansions of random vectors, second-order moments of random vectors, generalization of the density concept, entropy of a distribution, direct evaluation of probabilities, and conditional probabilities. The text then examines projections of random vector

  1. A basic course in probability theory

    CERN Document Server

    Bhattacharya, Rabi

    2016-01-01

    This text develops the necessary background in probability theory underlying diverse treatments of stochastic processes and their wide-ranging applications. In this second edition, the text has been reorganized for didactic purposes, new exercises have been added and basic theory has been expanded. General Markov dependent sequences and their convergence to equilibrium is the subject of an entirely new chapter. The introduction of conditional expectation and conditional probability very early in the text maintains the pedagogic innovation of the first edition; conditional expectation is illustrated in detail in the context of an expanded treatment of martingales, the Markov property, and the strong Markov property. Weak convergence of probabilities on metric spaces and Brownian motion are two topics to highlight. A selection of large deviation and/or concentration inequalities ranging from those of Chebyshev, Cramer–Chernoff, Bahadur–Rao, to Hoeffding have been added, with illustrative comparisons of thei...

  2. A probability space for quantum models

    Science.gov (United States)

    Lemmens, L. F.

    2017-06-01

    A probability space contains a set of outcomes, a collection of events formed by subsets of the set of outcomes and probabilities defined for all events. A reformulation in terms of propositions allows to use the maximum entropy method to assign the probabilities taking some constraints into account. The construction of a probability space for quantum models is determined by the choice of propositions, choosing the constraints and making the probability assignment by the maximum entropy method. This approach shows, how typical quantum distributions such as Maxwell-Boltzmann, Fermi-Dirac and Bose-Einstein are partly related with well-known classical distributions. The relation between the conditional probability density, given some averages as constraints and the appropriate ensemble is elucidated.

  3. Probability Issues in without Replacement Sampling

    Science.gov (United States)

    Joarder, A. H.; Al-Sabah, W. S.

    2007-01-01

    Sampling without replacement is an important aspect in teaching conditional probabilities in elementary statistics courses. Different methods proposed in different texts for calculating probabilities of events in this context are reviewed and their relative merits and limitations in applications are pinpointed. An alternative representation of…

  4. Wire system aging assessment and condition monitoring (WASCO)

    International Nuclear Information System (INIS)

    Fantoni, P.F.

    2007-04-01

    Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report contains some test results of a method for wire system condition monitoring, developed at the Halden Reactor Project, called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. (au)

  5. Handwriting, Visuomotor Integration, and Neurological Condition at School Age

    Science.gov (United States)

    Van Hoorn, Jessika F.; Maathuis, Carel G. B.; Peters, Lieke H. J.; Hadders-Algra, Mijna

    2010-01-01

    Aim: The study investigated the relationships between handwriting, visuomotor integration, and neurological condition. We paid particular attention to the presence of minor neurological dysfunction (MND). Method : Participants were 200 children (131 males, 69 females; age range 8-13y) of whom 118 received mainstream education (mean age 10y 5mo, SD…

  6. Transformer ageing modern condition monitoring techniques and their interpretations

    CERN Document Server

    Purkait, Prithwiraj

    2017-01-01

    This book is a one-stop guide to state-of-the-art research in transformer ageing, condition monitoring and diagnosis. It is backed by rigorous research projects supported by the Australian Research Council in collaboration with several transmission and distribution companies. Many of the diagnostic techniques and tools developed in these projects have been applied by electricity utilities and would appeal to both researchers and practicing engineers. Important topics covered in this book include transformer insulation materials and their ageing behaviour, transformer condition monitoring techniques and detailed diagnostic techniques and their interpretation schemes. It also features a monitoring framework for smart transformers as well as a chapter on biodegradable oil.

  7. A developmental study of risky decisions on the cake gambling task: age and gender analyses of probability estimation and reward evaluation.

    Science.gov (United States)

    Van Leijenhorst, Linda; Westenberg, P Michiel; Crone, Eveline A

    2008-01-01

    Decision making, or the process of choosing between competing courses of actions, is highly sensitive to age-related change, showing development throughout adolescence. In this study, we tested whether the development of decision making under risk is related to changes in risk-estimation abilities. Participants (N = 93) between ages 8-30 performed a child friendly gambling task, the Cake Gambling task, which was inspired by the Cambridge Gambling Task (Rogers et al., 1999), which has previously been shown to be sensitive to orbitofrontal cortex (OFC) damage. The task allowed comparisons of the contributions to risk perception of (1) the ability to estimate probabilities and (2) evaluate rewards. Adult performance patterns were highly similar to those found in previous reports, showing increased risk taking with increases in the probability of winning and the magnitude of potential reward. Behavioral patterns in children and adolescents did not differ from adult patterns, showing a similar ability for probability estimation and reward evaluation. These data suggest that participants 8 years and older perform like adults in a gambling task, previously shown to depend on the OFC in which all the information needed to make an advantageous decision is given on each trial and no information needs to be inferred from previous behavior. Interestingly, at all ages, females were more risk-averse than males. These results suggest that the increase in real-life risky behavior that is seen in adolescence is not a consequence of changes in risk perception abilities. The findings are discussed in relation to theories about the protracted development of the prefrontal cortex.

  8. Neighborhood Conditions and Psychosocial Outcomes Among Middle-Aged African Americans.

    Science.gov (United States)

    Tabet, Maya; Sanders, Erin A; Schootman, Mario; Chang, Jen Jen; Wolinsky, Fredric D; Malmstrom, Theodore K; Miller, Douglas K

    2017-04-01

    We examined associations between observed neighborhood conditions (good/adverse) and psychosocial outcomes (stress, depressive symptoms, resilience, and sense of control) among middle-aged and older African Americans. The sample included 455 middle-aged and older African Americans examined in Wave 10 of the African American Health (AAH) study. Linear regression was adjusted for attrition, self-selection into neighborhoods, and potential confounders, and stratified by the duration at current address (stress (standardized β = -0.18; P = .002) and depressive symptoms (standardized β = -0.12; P = .048). Among those who lived at their current address for stress (standardized β = 0.18; P = .305) or depressive symptoms (standardized β = 0.36; P = .080). Neighborhood conditions appear to have significant, complex associations with psychosocial factors among middle-aged and older African Americans. This holds important policy implications, especially since adverse neighborhood conditions may still result in adverse physical health outcomes in individuals with >5 years at current residence despite being associated with better psychosocial outcomes.

  9. Elements of probability and statistics an introduction to probability with De Finetti’s approach and to Bayesian statistics

    CERN Document Server

    Biagini, Francesca

    2016-01-01

    This book provides an introduction to elementary probability and to Bayesian statistics using de Finetti's subjectivist approach. One of the features of this approach is that it does not require the introduction of sample space – a non-intrinsic concept that makes the treatment of elementary probability unnecessarily complicate – but introduces as fundamental the concept of random numbers directly related to their interpretation in applications. Events become a particular case of random numbers and probability a particular case of expectation when it is applied to events. The subjective evaluation of expectation and of conditional expectation is based on an economic choice of an acceptable bet or penalty. The properties of expectation and conditional expectation are derived by applying a coherence criterion that the evaluation has to follow. The book is suitable for all introductory courses in probability and statistics for students in Mathematics, Informatics, Engineering, and Physics.

  10. Nuclear data uncertainties: I, Basic concepts of probability

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D.L.

    1988-12-01

    Some basic concepts of probability theory are presented from a nuclear-data perspective, in order to provide a foundation for thorough understanding of the role of uncertainties in nuclear data research. Topics included in this report are: events, event spaces, calculus of events, randomness, random variables, random-variable distributions, intuitive and axiomatic probability, calculus of probability, conditional probability and independence, probability distributions, binomial and multinomial probability, Poisson and interval probability, normal probability, the relationships existing between these probability laws, and Bayes' theorem. This treatment emphasizes the practical application of basic mathematical concepts to nuclear data research, and it includes numerous simple examples. 34 refs.

  11. Nuclear data uncertainties: I, Basic concepts of probability

    International Nuclear Information System (INIS)

    Smith, D.L.

    1988-12-01

    Some basic concepts of probability theory are presented from a nuclear-data perspective, in order to provide a foundation for thorough understanding of the role of uncertainties in nuclear data research. Topics included in this report are: events, event spaces, calculus of events, randomness, random variables, random-variable distributions, intuitive and axiomatic probability, calculus of probability, conditional probability and independence, probability distributions, binomial and multinomial probability, Poisson and interval probability, normal probability, the relationships existing between these probability laws, and Bayes' theorem. This treatment emphasizes the practical application of basic mathematical concepts to nuclear data research, and it includes numerous simple examples. 34 refs

  12. Estimating the empirical probability of submarine landslide occurrence

    Science.gov (United States)

    Geist, Eric L.; Parsons, Thomas E.; Mosher, David C.; Shipp, Craig; Moscardelli, Lorena; Chaytor, Jason D.; Baxter, Christopher D. P.; Lee, Homa J.; Urgeles, Roger

    2010-01-01

    The empirical probability for the occurrence of submarine landslides at a given location can be estimated from age dates of past landslides. In this study, tools developed to estimate earthquake probability from paleoseismic horizons are adapted to estimate submarine landslide probability. In both types of estimates, one has to account for the uncertainty associated with age-dating individual events as well as the open time intervals before and after the observed sequence of landslides. For observed sequences of submarine landslides, we typically only have the age date of the youngest event and possibly of a seismic horizon that lies below the oldest event in a landslide sequence. We use an empirical Bayes analysis based on the Poisson-Gamma conjugate prior model specifically applied to the landslide probability problem. This model assumes that landslide events as imaged in geophysical data are independent and occur in time according to a Poisson distribution characterized by a rate parameter λ. With this method, we are able to estimate the most likely value of λ and, importantly, the range of uncertainty in this estimate. Examples considered include landslide sequences observed in the Santa Barbara Channel, California, and in Port Valdez, Alaska. We confirm that given the uncertainties of age dating that landslide complexes can be treated as single events by performing statistical test of age dates representing the main failure episode of the Holocene Storegga landslide complex.

  13. Internal Medicine residents use heuristics to estimate disease probability.

    Science.gov (United States)

    Phang, Sen Han; Ravani, Pietro; Schaefer, Jeffrey; Wright, Bruce; McLaughlin, Kevin

    2015-01-01

    Training in Bayesian reasoning may have limited impact on accuracy of probability estimates. In this study, our goal was to explore whether residents previously exposed to Bayesian reasoning use heuristics rather than Bayesian reasoning to estimate disease probabilities. We predicted that if residents use heuristics then post-test probability estimates would be increased by non-discriminating clinical features or a high anchor for a target condition. We randomized 55 Internal Medicine residents to different versions of four clinical vignettes and asked them to estimate probabilities of target conditions. We manipulated the clinical data for each vignette to be consistent with either 1) using a representative heuristic, by adding non-discriminating prototypical clinical features of the target condition, or 2) using anchoring with adjustment heuristic, by providing a high or low anchor for the target condition. When presented with additional non-discriminating data the odds of diagnosing the target condition were increased (odds ratio (OR) 2.83, 95% confidence interval [1.30, 6.15], p = 0.009). Similarly, the odds of diagnosing the target condition were increased when a high anchor preceded the vignette (OR 2.04, [1.09, 3.81], p = 0.025). Our findings suggest that despite previous exposure to the use of Bayesian reasoning, residents use heuristics, such as the representative heuristic and anchoring with adjustment, to estimate probabilities. Potential reasons for attribute substitution include the relative cognitive ease of heuristics vs. Bayesian reasoning or perhaps residents in their clinical practice use gist traces rather than precise probability estimates when diagnosing.

  14. Probability: A Matter of Life and Death

    Science.gov (United States)

    Hassani, Mehdi; Kippen, Rebecca; Mills, Terence

    2016-01-01

    Life tables are mathematical tables that document probabilities of dying and life expectancies at different ages in a society. Thus, the life table contains some essential features of the health of a population. Probability is often regarded as a difficult branch of mathematics. Life tables provide an interesting approach to introducing concepts…

  15. Paraconsistent Probabilities: Consistency, Contradictions and Bayes’ Theorem

    Directory of Open Access Journals (Sweden)

    Juliana Bueno-Soler

    2016-09-01

    Full Text Available This paper represents the first steps towards constructing a paraconsistent theory of probability based on the Logics of Formal Inconsistency (LFIs. We show that LFIs encode very naturally an extension of the notion of probability able to express sophisticated probabilistic reasoning under contradictions employing appropriate notions of conditional probability and paraconsistent updating, via a version of Bayes’ theorem for conditionalization. We argue that the dissimilarity between the notions of inconsistency and contradiction, one of the pillars of LFIs, plays a central role in our extended notion of probability. Some critical historical and conceptual points about probability theory are also reviewed.

  16. Men who work at age 70 or older.

    Science.gov (United States)

    Ozawa, Martha N; Lum, Terry Y

    2005-01-01

    The federal policy on older workers has shifted from the encouragement of early withdrawal from the labor force to the encouragement of continuous participation in the labor force. In this light, it is instructive to investigate the backgrounds of elderly people who work at age 70 or older. This article presents the findings of a study, using data from the 1993 Asset and Health Dynamics of the Oldest Old Study, that investigated the effects of health, economic conditions (net worth, employer-provided pensions, and supplemental medical insurance coverage), education, and spouse's work status on the probability of working among men aged 70 or older. The study addressed the probability of working, the probability of working fulltime and of working part-time, and the probability of being self-employed and of being employed by others. Implications for policy are discussed.

  17. Invariant probabilities of transition functions

    CERN Document Server

    Zaharopol, Radu

    2014-01-01

    The structure of the set of all the invariant probabilities and the structure of various types of individual invariant probabilities of a transition function are two topics of significant interest in the theory of transition functions, and are studied in this book. The results obtained are useful in ergodic theory and the theory of dynamical systems, which, in turn, can be applied in various other areas (like number theory). They are illustrated using transition functions defined by flows, semiflows, and one-parameter convolution semigroups of probability measures. In this book, all results on transition probabilities that have been published by the author between 2004 and 2008 are extended to transition functions. The proofs of the results obtained are new. For transition functions that satisfy very general conditions the book describes an ergodic decomposition that provides relevant information on the structure of the corresponding set of invariant probabilities. Ergodic decomposition means a splitting of t...

  18. Human Error Probability Assessment During Maintenance Activities of Marine Systems

    Directory of Open Access Journals (Sweden)

    Rabiul Islam

    2018-03-01

    Full Text Available Background: Maintenance operations on-board ships are highly demanding. Maintenance operations are intensive activities requiring high man–machine interactions in challenging and evolving conditions. The evolving conditions are weather conditions, workplace temperature, ship motion, noise and vibration, and workload and stress. For example, extreme weather condition affects seafarers' performance, increasing the chances of error, and, consequently, can cause injuries or fatalities to personnel. An effective human error probability model is required to better manage maintenance on-board ships. The developed model would assist in developing and maintaining effective risk management protocols. Thus, the objective of this study is to develop a human error probability model considering various internal and external factors affecting seafarers' performance. Methods: The human error probability model is developed using probability theory applied to Bayesian network. The model is tested using the data received through the developed questionnaire survey of >200 experienced seafarers with >5 years of experience. The model developed in this study is used to find out the reliability of human performance on particular maintenance activities. Results: The developed methodology is tested on the maintenance of marine engine's cooling water pump for engine department and anchor windlass for deck department. In the considered case studies, human error probabilities are estimated in various scenarios and the results are compared between the scenarios and the different seafarer categories. The results of the case studies for both departments are also compared. Conclusion: The developed model is effective in assessing human error probabilities. These probabilities would get dynamically updated as and when new information is available on changes in either internal (i.e., training, experience, and fatigue or external (i.e., environmental and operational conditions

  19. Collapse susceptibility mapping in karstified gypsum terrain (Sivas basin - Turkey) by conditional probability, logistic regression, artificial neural network models

    Science.gov (United States)

    Yilmaz, Isik; Keskin, Inan; Marschalko, Marian; Bednarik, Martin

    2010-05-01

    This study compares the GIS based collapse susceptibility mapping methods such as; conditional probability (CP), logistic regression (LR) and artificial neural networks (ANN) applied in gypsum rock masses in Sivas basin (Turkey). Digital Elevation Model (DEM) was first constructed using GIS software. Collapse-related factors, directly or indirectly related to the causes of collapse occurrence, such as distance from faults, slope angle and aspect, topographical elevation, distance from drainage, topographic wetness index- TWI, stream power index- SPI, Normalized Difference Vegetation Index (NDVI) by means of vegetation cover, distance from roads and settlements were used in the collapse susceptibility analyses. In the last stage of the analyses, collapse susceptibility maps were produced from CP, LR and ANN models, and they were then compared by means of their validations. Area Under Curve (AUC) values obtained from all three methodologies showed that the map obtained from ANN model looks like more accurate than the other models, and the results also showed that the artificial neural networks is a usefull tool in preparation of collapse susceptibility map and highly compatible with GIS operating features. Key words: Collapse; doline; susceptibility map; gypsum; GIS; conditional probability; logistic regression; artificial neural networks.

  20. Effects of aging on blood pressure variability in resting conditions

    NARCIS (Netherlands)

    Veerman, D. P.; Imholz, B. P.; Wieling, W.; Karemaker, J. M.; van Montfrans, G. A.

    1994-01-01

    The objective of this study was to determine the effect of aging on beat-to-beat blood pressure and pulse interval variability in resting conditions and to determine the effect of aging on the sympathetic and vagal influence on the cardiovascular system by power spectral analysis of blood pressure

  1. Probabilities on Streams and Reflexive Games

    Directory of Open Access Journals (Sweden)

    Andrew Schumann

    2014-01-01

    Full Text Available Probability measures on streams (e.g. on hypernumbers and p-adic numbers have been defined. It was shown that these probabilities can be used for simulations of reflexive games. In particular, it can be proved that Aumann's agreement theorem does not hold for these probabilities. Instead of this theorem, there is a statement that is called the reflexion disagreement theorem. Based on this theorem, probabilistic and knowledge conditions can be defined for reflexive games at various reflexion levels up to the infinite level. (original abstract

  2. Performance of asphaltic concrete incorporating styrene butadiene rubber subjected to varying aging condition

    Science.gov (United States)

    Salah, Faisal Mohammed; Jaya, Ramadhansyah Putra; Mohamed, Azman; Hassan, Norhidayah Abdul; Rosni, Nurul Najihah Mad; Mohamed, Abdullahi Ali; Agussabti

    2017-12-01

    The influence of styrene butadiene rubber (SBR) on asphaltic concrete properties at different aging conditions was presented in this study. These aging conditions were named as un-aged, short-term, and long-term aging. The conventional asphalt binder of penetration grade 60/70 was used in this work. Four different levels of SBR addition were employed (i.e., 0 %, 1 %, 3 %, and 5 % by binder weight). Asphalt concrete mixes were prepared at selected optimum asphalt content (5 %). The performance was evaluated based on Marshall Stability, resilient modulus, and dynamic creep tests. Results indicated the improving stability and permanent deformation characteristics that the mixes modified with SBR polymer have under aging conditions. The result also showed that the stability, resilient modulus, and dynamic creep tests have the highest rates compared to the short-term aging and un-aged samples. Thus, the use of 5 % SBR can produce more durable asphalt concrete mixtures with better serviceability.

  3. The Impact of Advanced Age on Driving Safety in Adults with Medical Conditions.

    Science.gov (United States)

    Moon, Sanghee; Ranchet, Maud; Akinwuntan, Abiodun Emmanuel; Tant, Mark; Carr, David Brian; Raji, Mukaila Ajiboye; Devos, Hannes

    2018-01-01

    Adults aged 85 and older, often referred to as the oldest-old, are the fastest-growing segment of the population. The rapidly increasing number of older adults with chronic and multiple medical conditions poses challenges regarding their driving safety. To investigate the effect of advanced age on driving safety in drivers with medical conditions. We categorized 3,425 drivers with preexisting medical conditions into four age groups: middle-aged (55-64 years, n = 1,386), young-old (65-74 years, n = 1,013), old-old (75-84 years, n = 803), or oldest-old (85 years and older, n = 223). All underwent a formal driving evaluation. The outcome measures included fitness to drive recommendation by the referring physician, comprehensive fitness to drive decision from an official driving evaluation center, history of motor vehicle crashes (MVCs), and history of traffic violations. The oldest-old reported more cardiopulmonary and visual conditions, but less neurological conditions than the old-old. Compared to the middle-aged, the oldest-old were more likely to be considered unfit to drive by the referring physicians (odds ratio [OR] = 4.47, 95% confidence interval [CI] 2.20-9.10) and by the official driving evaluation center (OR = 2.74, 95% CI 1.87-4.03). The oldest-old reported more MVCs (OR = 2.79, 95% CI 1.88-4.12) compared to the middle-aged. Advanced age adversely affected driving safety outcomes. The oldest-old are a unique age group with medical conditions known to interfere with safe driving. Driving safety strategies should particularly target the oldest-old since they are the fastest-growing group and their increased frailty is associated with severe or fatal injuries due to MVCs. © 2018 S. Karger AG, Basel.

  4. Contributions to quantum probability

    International Nuclear Information System (INIS)

    Fritz, Tobias

    2010-01-01

    Chapter 1: On the existence of quantum representations for two dichotomic measurements. Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial dynamics. The solution uses methods from the theory of operator algebras and the theory of moment problems. The ensuing conditions reveal surprisingly simple relations between certain quantum-mechanical probabilities. It also shown that generally, none of these relations holds in general probabilistic models. This result might facilitate further experimental discrimination between quantum mechanics and other general probabilistic theories. Chapter 2: Possibilistic Physics. I try to outline a framework for fundamental physics where the concept of probability gets replaced by the concept of possibility. Whereas a probabilistic theory assigns a state-dependent probability value to each outcome of each measurement, a possibilistic theory merely assigns one of the state-dependent labels ''possible to occur'' or ''impossible to occur'' to each outcome of each measurement. It is argued that Spekkens' combinatorial toy theory of quantum mechanics is inconsistent in a probabilistic framework, but can be regarded as possibilistic. Then, I introduce the concept of possibilistic local hidden variable models and derive a class of possibilistic Bell inequalities which are violated for the possibilistic Popescu-Rohrlich boxes. The chapter ends with a philosophical discussion on possibilistic vs. probabilistic. It can be argued that, due to better falsifiability properties, a possibilistic theory has higher predictive power than a probabilistic one. Chapter 3: The quantum region for von Neumann measurements with postselection. It is determined under which conditions a probability distribution on a finite set can occur as the outcome

  5. Thermal disadvantage factor calculation by the multiregion collision probability method

    International Nuclear Information System (INIS)

    Ozgener, B.; Ozgener, H.A.

    2004-01-01

    A multi-region collision probability formulation that is capable of applying white boundary condition directly is presented and applied to thermal neutron transport problems. The disadvantage factors computed are compared with their counterparts calculated by S N methods with both direct and indirect application of white boundary condition. The results of the ABH and collision probability method with indirect application of white boundary condition are also considered and comparisons with benchmark Monte Carlo results are carried out. The studies show that the proposed formulation is capable of calculating thermal disadvantage factor with sufficient accuracy without resorting to the fictitious scattering outer shell approximation associated with the indirect application of the white boundary condition in collision probability solutions

  6. ASSESSMENT OF CABLE AGING USING CONDITION MONITORING TECHNIQUES

    International Nuclear Information System (INIS)

    GROVE, E.; LOFARO, R.; SOO, P.; VILLARAN, M.; HSU, F.

    2000-01-01

    Electric cables in nuclear power plants suffer degradation during service as a result of the thermal and radiation environments in which they are installed. Instrumentation and control cables are one type of cable that provide an important role in reactor safety. Should the polymeric cable insulation material become embrittled and cracked during service, or during a loss-of-coolant-accident (LOCA) and when steam and high radiation conditions are anticipated, failure could occur and prevent the cables from fulfilling their intended safety function(s). A research program is being conducted at Brookhaven National Laboratory to evaluate condition monitoring (CM) techniques for estimating the amount of cable degradation experienced during in-plant service. The objectives of this program are to assess the ability of the cables to perform under a simulated LOCA without losing their ability to function effectively, and to identify CM techniques which may be used to determine the effective lifetime of cables. The cable insulation materials tested include ethylene propylene rubber (EPR) and cross-linked polyethylene (XLPE). Accelerated aging (thermal and radiation) to the equivalent of 40 years of service was performed, followed by exposure to simulated LOCA conditions. The effectiveness of chemical, electrical, and mechanical condition monitoring techniques are being evaluated. Results indicate that several of these methods can detect changes in material parameters with increasing age. However, each has its limitations, and a combination of methods may provide an effective means for trending cable degradation in order to assess the remaining life of cables

  7. Exploring non-signalling polytopes with negative probability

    International Nuclear Information System (INIS)

    Oas, G; Barros, J Acacio de; Carvalhaes, C

    2014-01-01

    Bipartite and tripartite EPR–Bell type systems are examined via joint quasi-probability distributions where probabilities are permitted to be negative. It is shown that such distributions exist only when the no-signalling condition is satisfied. A characteristic measure, the probability mass, is introduced and, via its minimization, limits the number of quasi-distributions describing a given marginal probability distribution. The minimized probability mass is shown to be an alternative way to characterize non-local systems. Non-signalling polytopes for two to eight settings in the bipartite scenario are examined and compared to prior work. Examining perfect cloning of non-local systems within the tripartite scenario suggests defining two categories of signalling. It is seen that many properties of non-local systems can be efficiently described by quasi-probability theory. (paper)

  8. On the Hitting Probability of Max-Stable Processes

    OpenAIRE

    Hofmann, Martin

    2012-01-01

    The probability that a max-stable process {\\eta} in C[0, 1] with identical marginal distribution function F hits x \\in R with 0 < F (x) < 1 is the hitting probability of x. We show that the hitting probability is always positive, unless the components of {\\eta} are completely dependent. Moreover, we consider the event that the paths of standard MSP hit some x \\in R twice and we give a sufficient condition for a positive probability of this event.

  9. Psychiatric and Medical Conditions in Transition-Aged Individuals With ASD.

    Science.gov (United States)

    Davignon, Meghan N; Qian, Yinge; Massolo, Maria; Croen, Lisa A

    2018-04-01

    Children with autism spectrum disorder (ASD) have a variety of medical and psychiatric conditions and an increased use of health care services. There is limited information about the prevalence of psychiatric and medical conditions in adolescents and young adults with ASD. Our objective was to describe the frequency of medical and psychiatric conditions in a large population of diverse, insured transition-aged individuals with ASD. Participants included Kaiser Permanente Northern California members who were enrolled from 2013 to 2015 and who were 14 to 25 years old. Individuals with ASD ( n = 4123) were compared with peers with attention-deficit/hyperactivity disorder ( n = 20 615), diabetes mellitus ( n = 2156), and typical controls with neither condition ( n = 20 615). Over one-third (34%) of individuals with ASD had a co-occurring psychiatric condition; the most commonly reported medical conditions included infections (42%), obesity (25%), neurologic conditions (18%), allergy and/or immunologic conditions (16%), musculoskeletal conditions (15%), and gastrointestinal (11%) conditions. After controlling for sex, age, race, and duration of Kaiser Permanente Northern California membership, most psychiatric conditions were significantly more common in the ASD group than in each comparison group, and most medical conditions were significantly more common in the ASD group than in the attention-deficit/hyperactivity disorder and typical control groups but were similar to or significantly less common than the diabetes mellitus group. Although more research is needed to identify factors contributing to this excess burden of disease, there is a pressing need for all clinicians to approach ASD as a chronic health condition requiring regular follow-up and routine screening and treatment of medical and psychiatric issues. Copyright © 2018 by the American Academy of Pediatrics.

  10. The Use of Conditional Probability Integral Transformation Method for Testing Accelerated Failure Time Models

    Directory of Open Access Journals (Sweden)

    Abdalla Ahmed Abdel-Ghaly

    2016-06-01

    Full Text Available This paper suggests the use of the conditional probability integral transformation (CPIT method as a goodness of fit (GOF technique in the field of accelerated life testing (ALT, specifically for validating the underlying distributional assumption in accelerated failure time (AFT model. The method is based on transforming the data into independent and identically distributed (i.i.d Uniform (0, 1 random variables and then applying the modified Watson statistic to test the uniformity of the transformed random variables. This technique is used to validate each of the exponential, Weibull and lognormal distributions' assumptions in AFT model under constant stress and complete sampling. The performance of the CPIT method is investigated via a simulation study. It is concluded that this method performs well in case of exponential and lognormal distributions. Finally, a real life example is provided to illustrate the application of the proposed procedure.

  11. Study on risk indicator for appropriate plant maintenance considering aging effect

    International Nuclear Information System (INIS)

    Mano, Akihiro; Yamaguchi, Akira; Takata, Takashi

    2014-01-01

    Since, nuclear power plants run for a long term and plant component may deteriorate due to aging, plant safety must be maintained through maintenance activities of components. The maintenance will become more important as the number of aged plant increases. In the planning of maintenance, one must select appropriate components and interval. In general, Fussell-Vesely importance (FV) and Risk Achievement Worth (RAW) are used as a risk indicator for the maintenance. A priority order of each component can be evaluated using those risk indicators at a certain condition. However, the influence of aging (time history) on the order cannot be estimated directly. In the paper, a change of conditional core damage probability (ΔCCDP) and a change of conditional containment failure probability (ΔCCFP) are proposed as additional indicators in which the aging effect is evaluated directly so as to determine the priority order. A simplified level one probabilistic risk assessment (PRA) has been carried out in order to investigate the change of the risk indicators by considering the change of a component failure probability due to aging. In the analyses, three conditions are assumed; base (original) state, aging state and further aging state without maintenance activities. It is demonstrated that the proposed indicator (ΔCCDP and ΔCCFP) reveals the aging effect of each component, while the change of the FV and RAW represent unrealistic behavior through the states. As a result, it is found that the ΔCCDP and ΔCCFP are superior to the others in terms of the ability to evaluate components appropriately in deteriorated (aging) states and take account of differences of deterioration behavior. It is also found that the priority order of the multiple-components maintenance at the same time can also be evaluated using the ΔCCDP and ΔCCFP. Additionally, a risk informed decision making based on the risk acceptance criteria can be discussed for the maintenance procedure using the

  12. Probable impact of age and hypoxia on proliferation and microRNA expression profile of bone marrow-derived human mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Norlaily Mohd Ali

    2016-01-01

    Full Text Available Decline in the therapeutic potential of bone marrow-derived mesenchymal stem cells (MSC is often seen with older donors as compared to young. Although hypoxia is known as an approach to improve the therapeutic potential of MSC in term of cell proliferation and differentiation capacity, its effects on MSC from aged donors have not been well studied. To evaluate the influence of hypoxia on different age groups, MSC from young (60 years donors were expanded under hypoxic (5% O2 and normal (20% O2 culture conditions. MSC from old donors exhibited a reduction in proliferation rate and differentiation potential together with the accumulation of senescence features compared to that of young donors. However, MSC cultured under hypoxic condition showed enhanced self-renewing and proliferation capacity in both age groups as compared to normal condition. Bioinformatic analysis of the gene ontology (GO and KEGG pathway under hypoxic culture condition identified hypoxia-inducible miRNAs that were found to target transcriptional activity leading to enhanced cell proliferation, migration as well as decrease in growth arrest and apoptosis through the activation of multiple signaling pathways. Overall, differentially expressed miRNA provided additional information to describe the biological changes of young and aged MSCs expansion under hypoxic culture condition at the molecular level. Based on our findings, the therapeutic potential hierarchy of MSC according to donor’s age group and culture conditions can be categorized in the following order: young (hypoxia > young (normoxia > old aged (hypoxia > old aged (normoxia.

  13. Transformation of even-aged European beech (Fagus sylvatica L.) to uneven-aged management under changing growth conditions caused by climate change

    DEFF Research Database (Denmark)

    Schou, Erik; Meilby, Henrik

    2013-01-01

    Transformation from even-aged to uneven-aged forest management is currently taking place throughout Europe. Climate change is, however, expected to change growth conditions—possibly quite radically. Using a deterministic approach, it was the objective of this study to investigate the influence...... of such changes on optimal transformation strategies for an even-aged stand of European Beech in Denmark. For a range of growth change scenarios, represented by changes in site index, optimal harvest policies were determined using a matrix modelling approach and a differential evolution algorithm. Transition...... probabilities were updated continuously based on stand level variables and the transition matrix was thus dynamic. With optimal transformation policies, stand development followed similar pathways during the transformation phase irrespective of climate change scenario. Optimal transformation policies were thus...

  14. Generalized Probability-Probability Plots

    NARCIS (Netherlands)

    Mushkudiani, N.A.; Einmahl, J.H.J.

    2004-01-01

    We introduce generalized Probability-Probability (P-P) plots in order to study the one-sample goodness-of-fit problem and the two-sample problem, for real valued data.These plots, that are constructed by indexing with the class of closed intervals, globally preserve the properties of classical P-P

  15. Quantum Probabilities as Behavioral Probabilities

    Directory of Open Access Journals (Sweden)

    Vyacheslav I. Yukalov

    2017-03-01

    Full Text Available We demonstrate that behavioral probabilities of human decision makers share many common features with quantum probabilities. This does not imply that humans are some quantum objects, but just shows that the mathematics of quantum theory is applicable to the description of human decision making. The applicability of quantum rules for describing decision making is connected with the nontrivial process of making decisions in the case of composite prospects under uncertainty. Such a process involves deliberations of a decision maker when making a choice. In addition to the evaluation of the utilities of considered prospects, real decision makers also appreciate their respective attractiveness. Therefore, human choice is not based solely on the utility of prospects, but includes the necessity of resolving the utility-attraction duality. In order to justify that human consciousness really functions similarly to the rules of quantum theory, we develop an approach defining human behavioral probabilities as the probabilities determined by quantum rules. We show that quantum behavioral probabilities of humans do not merely explain qualitatively how human decisions are made, but they predict quantitative values of the behavioral probabilities. Analyzing a large set of empirical data, we find good quantitative agreement between theoretical predictions and observed experimental data.

  16. Electrical-Based Diagnostic Techniques for Assessing Insulation Condition in Aged Transformers

    Directory of Open Access Journals (Sweden)

    Issouf Fofana

    2016-08-01

    Full Text Available The condition of the internal cellulosic paper and oil insulation are of concern for the performance of power transformers. Over the years, a number of methods have been developed to diagnose and monitor the degradation/aging of the transformer internal insulation system. Some of this degradation/aging can be assessed from electrical responses. Currently there are a variety of electrical-based diagnostic techniques available for insulation condition monitoring of power transformers. In most cases, the electrical signals being monitored are due to mechanical or electric changes caused by physical changes in resistivity, inductance or capacitance, moisture, contamination or aging by-products in the insulation. This paper presents a description of commonly used and modern electrical-based diagnostic techniques along with their interpretation schemes.

  17. Probability Aggregates in Probability Answer Set Programming

    OpenAIRE

    Saad, Emad

    2013-01-01

    Probability answer set programming is a declarative programming that has been shown effective for representing and reasoning about a variety of probability reasoning tasks. However, the lack of probability aggregates, e.g. {\\em expected values}, in the language of disjunctive hybrid probability logic programs (DHPP) disallows the natural and concise representation of many interesting problems. In this paper, we extend DHPP to allow arbitrary probability aggregates. We introduce two types of p...

  18. Aging and condition monitoring of electric cables in nuclear power plants

    International Nuclear Information System (INIS)

    Lofaro, R.J.; Grove, E.; Soo, P.

    1998-05-01

    There are a variety of environmental stressors in nuclear power plants that can influence the aging rate of components; these include elevated temperatures, high radiation fields, and humid conditions. Exposure to these stressors over long periods of time can cause degradation of components that may go undetected unless the aging mechanisms are identified and monitored. In some cases the degradation may be mitigated by maintenance or replacement. However, some components receive neither and are thus more susceptible to aging degradation, which might lead to failure. One class of components that falls in this category is electric cables. Cables are very often overlooked in aging analyses since they are passive components that require no maintenance. However, they are very important components since they provide power to safety related equipment and transmit signals to and from instruments and controls. This paper will look at the various aging mechanisms and failure modes associated with electric cables. Condition monitoring techniques that may be useful for monitoring degradation of cables will also be discussed

  19. Handwriting, visuomotor integration, and neurological condition at school age

    NARCIS (Netherlands)

    van Hoorn, Jessika F.; Maathuis, Carel G. B.; Peters, Lieke H. J.; Hadders-Algra, Mijna

    2010-01-01

    Aim The study investigated the relationships between handwriting, visuomotor integration, and neurological condition. We paid particular attention to the presence of minor neurological dysfunction (MND). Method Participants were 200 children (131 males, 69 females; age range 8-13y) of whom 118

  20. Contributions to quantum probability

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, Tobias

    2010-06-25

    Chapter 1: On the existence of quantum representations for two dichotomic measurements. Under which conditions do outcome probabilities of measurements possess a quantum-mechanical model? This kind of problem is solved here for the case of two dichotomic von Neumann measurements which can be applied repeatedly to a quantum system with trivial dynamics. The solution uses methods from the theory of operator algebras and the theory of moment problems. The ensuing conditions reveal surprisingly simple relations between certain quantum-mechanical probabilities. It also shown that generally, none of these relations holds in general probabilistic models. This result might facilitate further experimental discrimination between quantum mechanics and other general probabilistic theories. Chapter 2: Possibilistic Physics. I try to outline a framework for fundamental physics where the concept of probability gets replaced by the concept of possibility. Whereas a probabilistic theory assigns a state-dependent probability value to each outcome of each measurement, a possibilistic theory merely assigns one of the state-dependent labels ''possible to occur'' or ''impossible to occur'' to each outcome of each measurement. It is argued that Spekkens' combinatorial toy theory of quantum mechanics is inconsistent in a probabilistic framework, but can be regarded as possibilistic. Then, I introduce the concept of possibilistic local hidden variable models and derive a class of possibilistic Bell inequalities which are violated for the possibilistic Popescu-Rohrlich boxes. The chapter ends with a philosophical discussion on possibilistic vs. probabilistic. It can be argued that, due to better falsifiability properties, a possibilistic theory has higher predictive power than a probabilistic one. Chapter 3: The quantum region for von Neumann measurements with postselection. It is determined under which conditions a probability distribution on a

  1. Risk, reward, and decision-making in a rodent model of cognitive aging

    Directory of Open Access Journals (Sweden)

    Ryan J Gilbert

    2012-01-01

    Full Text Available Impaired decision-making in aging can directly impact factors (financial security, quality of healthcare that are critical to maintaining quality of life and independence at advanced ages. Naturalistic rodent models mimic human aging in other cognitive domains, and afford the opportunity to parse the effects of age on discrete aspects of decision-making in a manner relatively uncontaminated by experiential factors. Young adult (5-7 mo. and aged (23-25 mo. male F344 rats were trained on a probability discounting task in which they made discrete-trial choices between a small certain reward (1 food pellet and a large but uncertain reward (2 food pellets with varying probabilities of delivery ranging from 100% to 0%. Young rats chose the large reward when it was associated with a high probability of delivery and shifted to the smaller but certain reward as probability of the large reward decreased. As a group, aged rats performed comparably to young, but there was significantly greater variance among aged rats. One subgroup of aged rats showed strong preference for the small certain reward. This preference was maintained under conditions in which large reward delivery was certain, suggesting decreased sensitivity to reward magnitude. In contrast, another subgroup of aged rats showed strong preference for the large reward at low probabilities of delivery. Interestingly, this subgroup also showed elevated preference for probabilistic rewards when reward magnitudes were equalized. Previous findings using this same aged study population described strongly attenuated discounting of delayed rewards with age, together suggesting that a subgroup of aged rats may have deficits associated with accounting for costs (i.e., delay, probability. These deficits in cost-accounting were dissociable from the age-related differences in sensitivity to reward magnitude, suggesting that aging influences multiple, distinct neural mechanisms that can impact cost

  2. Risk, reward, and decision-making in a rodent model of cognitive aging.

    Science.gov (United States)

    Gilbert, Ryan J; Mitchell, Marci R; Simon, Nicholas W; Bañuelos, Cristina; Setlow, Barry; Bizon, Jennifer L

    2011-01-01

    Impaired decision-making in aging can directly impact factors (financial security, health care) that are critical to maintaining quality of life and independence at advanced ages. Naturalistic rodent models mimic human aging in other cognitive domains, and afford the opportunity to parse the effects of age on discrete aspects of decision-making in a manner relatively uncontaminated by experiential factors. Young adult (5-7 months) and aged (23-25 months) male F344 rats were trained on a probability discounting task in which they made discrete-trial choices between a small certain reward (one food pellet) and a large but uncertain reward (two food pellets with varying probabilities of delivery ranging from 100 to 0%). Young rats chose the large reward when it was associated with a high probability of delivery and shifted to the small but certain reward as probability of the large reward decreased. As a group, aged rats performed comparably to young, but there was significantly greater variance among aged rats. One subgroup of aged rats showed strong preference for the small certain reward. This preference was maintained under conditions in which large reward delivery was also certain, suggesting decreased sensitivity to reward magnitude. In contrast, another subgroup of aged rats showed strong preference for the large reward at low probabilities of delivery. Interestingly, this subgroup also showed elevated preference for probabilistic rewards when reward magnitudes were equalized. Previous findings using this same aged study population described strongly attenuated discounting of delayed rewards with age, together suggesting that a subgroup of aged rats may have deficits associated with accounting for reward costs (i.e., delay or probability). These deficits in cost-accounting were dissociable from the age-related differences in sensitivity to reward magnitude, suggesting that aging influences multiple, distinct mechanisms that can impact cost-benefit decision-making.

  3. Frequency of vaginal conditional-pathogenic microflora dependency from age in conditions of normocenosis and disbiosis

    OpenAIRE

    Gruzevsky, A. A.; Zyablitsev, S. V.; Chernobrivtsev, P. A.

    2017-01-01

    Gruzevsky A. A., Zyablitsev S. V., Chernobrivtsev P. A. Frequency of vaginal conditional-pathogenic microflora dependency from age in conditions of normocenosis and disbiosis. Journal of Education, Health and Sport. 2017;7(2):509-522. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.399315 http://ojs.ukw.edu.pl/index.php/johs/article/view/4360 The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 1223 (...

  4. Effects of surface conditioning on repair bond strengths of non-aged and aged microhybrid, nanohybrid, and nanofilled composite resins

    NARCIS (Netherlands)

    Rinastiti, Margareta; Siswomihardjo, Widowati; Busscher, Henk J.; Ozcan, Mutlu

    2011-01-01

    This study evaluates effects of aging on repair bond strengths of microhybrid, nanohybrid, and nanofilled composite resins and characterizes the interacting surfaces after aging. Disk-shaped composite specimens were assigned to one of three aging conditions: (1) thermocycling (5,000x, 5-55 degrees

  5. Statistics concerning the Apollo command module water landing, including the probability of occurrence of various impact conditions, sucessful impact, and body X-axis loads

    Science.gov (United States)

    Whitnah, A. M.; Howes, D. B.

    1971-01-01

    Statistical information for the Apollo command module water landings is presented. This information includes the probability of occurrence of various impact conditions, a successful impact, and body X-axis loads of various magnitudes.

  6. On the use of mean groundwater age, life expectancy and capture probability for defining aquifer vulnerability and time-of-travel zones for source water protection.

    Science.gov (United States)

    Molson, J W; Frind, E O

    2012-01-01

    Protection and sustainability of water supply wells requires the assessment of vulnerability to contamination and the delineation of well capture zones. Capture zones, or more generally, time-of-travel zones corresponding to specific contaminant travel times, are most commonly delineated using advective particle tracking. More recently, the capture probability approach has been used in which a probability of capture of P=1 is assigned to the well and the growth of a probability-of-capture plume is tracked backward in time using an advective-dispersive transport model. This approach accounts for uncertainty due to local-scale heterogeneities through the use of macrodispersion. In this paper, we develop an alternative approach to capture zone delineation by applying the concept of mean life expectancy E (time remaining before being captured by the well), and we show how life expectancy E is related to capture probability P. Either approach can be used to delineate time-of-travel zones corresponding to specific travel times, as well as the ultimate capture zone. The related concept of mean groundwater age A (time since recharge) can also be applied in the context of defining the vulnerability of a pumped aquifer. In the same way as capture probability, mean life expectancy and groundwater age account for local-scale uncertainty or unresolved heterogeneities through macrodispersion, which standard particle tracking neglects. The approach is tested on 2D and 3D idealized systems, as well as on several watershed-scale well fields within the Regional Municipality of Waterloo, Ontario, Canada. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. [Socio-demographics characteristics and health conditions of older homeless persons of Lima, Peru].

    Science.gov (United States)

    Moquillaza-Risco, Marlene; León, Elsa; Dongo, Mario; Munayco, César V

    2015-10-01

    Determine the socio-demographics characteristics and health conditions of older homeless persons at the time of enrollment into the National Program "Vida Digna" and the probability of functional dependency by age, and stratified by gender and cognitive impairment. MATERIALS ANDE METHODS: We performed a cross sectional study, reviewing all registration forms of the program in order to identify socio-demographic variables and health conditions of older homeless persons at the time of enrollment in the program. We did a descriptive analysis of the socio-demographic variables and we also determined the frequency of health conditions. Furthermore, we determined the probability of functional dependency by age, and stratified by gender and cognitive impairment through a logistic regression model. The older homeless persons at the time of enrollment in the program were mostly single men, with a primary education or no education. The study subjects had a high frequency of chronic and mental diseases. 50% of them had certain level of functional impairment and roughly 70% had a certain level of cognitive impairment. The probability of functional dependency increased by age, and it was higher in women than in men. This probability increased according to the level of cognitive impairment. This study shows that older homeless persons are a vulnerable population not only because they live outdoors but also because they a have also for the high prevalence of chronic and mental diseases. These diseases prevent the homeless persons from living by themselves special care to overcome their situations.

  8. Dependency models and probability of joint events

    International Nuclear Information System (INIS)

    Oerjasaeter, O.

    1982-08-01

    Probabilistic dependencies between components/systems are discussed with reference to a broad classification of potential failure mechanisms. Further, a generalized time-dependency model, based on conditional probabilities for estimation of the probability of joint events and event sequences is described. The applicability of this model is clarified/demonstrated by various examples. It is concluded that the described model of dependency is a useful tool for solving a variety of practical problems concerning the probability of joint events and event sequences where common cause and time-dependent failure mechanisms are involved. (Auth.)

  9. Environmental conditions can modulate the links among oxidative stress, age, and longevity.

    Science.gov (United States)

    Marasco, Valeria; Stier, Antoine; Boner, Winnie; Griffiths, Kate; Heidinger, Britt; Monaghan, Pat

    2017-06-01

    Understanding the links between environmental conditions and longevity remains a major focus in biological research. We examined within-individual changes between early- and mid-adulthood in the circulating levels of four oxidative stress markers linked to ageing, using zebra finches (Taeniopygia guttata): a DNA damage product (8-hydroxy-2'-deoxyguanosine; 8-OHdG), protein carbonyls (PC), non-enzymatic antioxidant capacity (OXY), and superoxide dismutase activity (SOD). We further examined whether such within-individual changes differed among birds living under control (ad lib food) or more challenging environmental conditions (unpredictable food availability), having previously found that the latter increased corticosterone levels when food was absent but improved survival over a three year period. Our key findings were: (i) 8-OHdG and PC increased with age in both environments, with a higher increase in 8-OHdG in the challenging environment; (ii) SOD increased with age in the controls but not in the challenged birds, while the opposite was true for OXY; (iii) control birds with high levels of 8-OHdG died at a younger age, but this was not the case in challenged birds. Our data clearly show that while exposure to the potentially damaging effects of oxidative stress increases with age, environmental conditions can modulate the pace of this age-related change. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Integrated failure probability estimation based on structural integrity analysis and failure data: Natural gas pipeline case

    International Nuclear Information System (INIS)

    Dundulis, Gintautas; Žutautaitė, Inga; Janulionis, Remigijus; Ušpuras, Eugenijus; Rimkevičius, Sigitas; Eid, Mohamed

    2016-01-01

    In this paper, the authors present an approach as an overall framework for the estimation of the failure probability of pipelines based on: the results of the deterministic-probabilistic structural integrity analysis (taking into account loads, material properties, geometry, boundary conditions, crack size, and defected zone thickness), the corrosion rate, the number of defects and failure data (involved into the model via application of Bayesian method). The proposed approach is applied to estimate the failure probability of a selected part of the Lithuanian natural gas transmission network. The presented approach for the estimation of integrated failure probability is a combination of several different analyses allowing us to obtain: the critical crack's length and depth, the failure probability of the defected zone thickness, dependency of the failure probability on the age of the natural gas transmission pipeline. A model's uncertainty analysis and uncertainty propagation analysis are performed, as well. - Highlights: • Degradation mechanisms of natural gas transmission pipelines. • Fracture mechanic analysis of the pipe with crack. • Stress evaluation of the pipe with critical crack. • Deterministic-probabilistic structural integrity analysis of gas pipeline. • Integrated estimation of pipeline failure probability by Bayesian method.

  11. CHRONIC MEDICAL CONDITIONS AND REPRODUCIBILITY OF SELF-REPORTED AGE AT MENOPAUSE AMONG COMMUNITY DWELLING WOMEN

    Science.gov (United States)

    de Vries, Heather F.; Northington, Gina M.; Kaye, Elise M.; Bogner, Hillary R.

    2011-01-01

    OBJECTIVE To examine the association between chronic medical conditions and reproducibility of self-reported age at menopause among community-dwelling women. METHOD Age at menopause was assessed in a population-based longitudinal survey of 240 women twice, in 1993 and 2004. Women who recalled age at menopause in 2004 within one year or less of the age at menopause recalled in 1993 (concordant) were compared with women who did not recall of age at menopause in 2004 within 1 year of age at menopause recalled in 1993 (discordant). Type of menopause (surgical or natural) and chronic medical conditions were assessed by self-report. RESULTS One hundred and forty three women (59.6%) reported surgical menopause and 97 (40.4%) reported natural menopause. In all, 130 (54.2%) of women recalled age at menopause in 2004 within one year or less of recalled age at menopause in 1994 while 110 (45.8%) women did not recall age at menopause in 2004 within one year or less of recalled age at menopause in 1994. Among women with surgical menopause, women with three or more medical conditions were less likely to have concordant recall of age at menopause than women with less than three chronic medical conditions (adjusted odds ratio (OR) = 0.36, 95% confidence interval (CI) [0.15, 0.91]) in multivariate models controlling for potentially influential characteristics including cognition and years from menopause. CONCLUSIONS Among women who underwent surgical menopause, the presence of three or more medical conditions is associated with decreased reproducibility of self-reported age at menopause. PMID:21971208

  12. Chronic medical conditions and reproducibility of self-reported age at menopause among community-dwelling women.

    Science.gov (United States)

    de Vries, Heather F; Northington, Gina M; Kaye, Elise M; Bogner, Hillary R

    2011-12-01

    The aim of this study was to examine the association between chronic medical conditions and reproducibility of self-reported age at menopause among community-dwelling women. Age at menopause was assessed in a population-based longitudinal survey of 240 women twice, in 1993 and 2004. Women who recalled age at menopause in 2004 within 1 year or less of age at menopause recalled in 1993 (concordant) were compared with women who did not recall age at menopause in 2004 within 1 year of age at menopause recalled in 1993 (discordant). Type of menopause (surgical or natural) and chronic medical conditions were assessed by self-report. One hundred forty-three women (59.6%) reported surgical menopause, and 97 (40.4%) reported natural menopause. In all, 130 (54.2%) women recalled age at menopause in 2004 within 1 year or less of recalled age at menopause in 1994, whereas 110 (45.8%) women did not recall age at menopause in 2004 within 1 year or less of recalled age at menopause in 1994. Among the women with surgical menopause, the women with three or more medical conditions were less likely to have concordant recall of age at menopause than the women with less than three chronic medical conditions (adjusted odds ratio, 0.36; 95% CI, 0.15-0.91) in multivariate models controlling for potentially influential characteristics including cognition and years since menopause. Among women who underwent surgical menopause, the presence of three or more medical conditions is associated with decreased reproducibility of self-reported age at menopause.

  13. Effects of Word Frequency and Transitional Probability on Word Reading Durations of Younger and Older Speakers.

    Science.gov (United States)

    Moers, Cornelia; Meyer, Antje; Janse, Esther

    2017-06-01

    High-frequency units are usually processed faster than low-frequency units in language comprehension and language production. Frequency effects have been shown for words as well as word combinations. Word co-occurrence effects can be operationalized in terms of transitional probability (TP). TPs reflect how probable a word is, conditioned by its right or left neighbouring word. This corpus study investigates whether three different age groups-younger children (8-12 years), adolescents (12-18 years) and older (62-95 years) Dutch speakers-show frequency and TP context effects on spoken word durations in reading aloud, and whether age groups differ in the size of these effects. Results show consistent effects of TP on word durations for all age groups. Thus, TP seems to influence the processing of words in context, beyond the well-established effect of word frequency, across the entire age range. However, the study also indicates that age groups differ in the size of TP effects, with older adults having smaller TP effects than adolescent readers. Our results show that probabilistic reduction effects in reading aloud may at least partly stem from contextual facilitation that leads to faster reading times in skilled readers, as well as in young language learners.

  14. Laboratory Measurements of Biomass Cook-stove Emissions Aged in an Oxidation Flow Reactor: Influence of Combustion and Aging Conditions on Aerosols

    Science.gov (United States)

    Grieshop, A. P.; Reece, S. M.; Sinha, A.; Wathore, R.

    2016-12-01

    Combustion in rudimentary and improved cook-stoves used by billions in developing countries can be a regionally dominant contributor to black carbon (BC), primary organic aerosols (POA) and precursors for secondary organic aerosol (SOA). Recent studies suggest that SOA formed during photo-oxidation of primary emissions from biomass burning may make important contribution to its atmospheric impacts. However, the extent to which stove type and operating conditions affect the amount, composition and characteristics of SOA formed from the aging of cookstoves emissions is still largely undetermined. Here we present results from experiments with a field portable oxidation flow reactor (F-OFR) designed to assess aging of cook-stove emissions in both laboratory and field settings. Laboratory tests results are used to compare the quantity and properties of fresh and aged emissions from a traditional open fire and twp alternative stove designs operated on the standard and alternate testing protocols. Diluted cookstove emissions were exposed to a range of oxidant concentrations in the F-OFR. Primary emissions were aged both on-line, to study the influence of combustion variability, and sampled from batched emissions in a smog chamber to examine different aging conditions. Data from real-time particle- and gas-phase instruments and integrated filter samples were collected up and down stream of the OFR. The properties of primary emissions vary strongly with stove type and combustion conditions (e.g. smoldering versus flaming). Experiments aging diluted biomass emissions from distinct phases of stove operation (smoldering and flaming) showed peak SOA production for both phases occurred between 3 and 6 equivalent days of aging with slightly greater production observed in flaming phase emissions. Changing combustion conditions had a stronger influence than aging on POA+SOA `emission factors'. Aerosol Chemical Speciation Monitor data show a substantial evolution of aerosol

  15. Technical evaluation on high aging, and performance conditions on long-term conservation program

    International Nuclear Information System (INIS)

    Yamashita, Atsushi

    2001-01-01

    In order to secure safety and safe operation of power plants, in every nuclear power plants, conservation actions based on preventive conservation are performed. They contain operative condition monitoring, patrolling inspection, and periodical tests on important systems and apparatus by operators under plant operation and condition monitoring by maintenance workers, and so on, and when finding out their abnormal conditions, their detailed survey is performed to adopt adequate countermeasures such as recovery, exchange, and so on. And, to equipments for nuclear power generation periodical conditions were obliged by legal examinations and by independent inspections. As a result of these conservation actions, even on a plant elapsed about 30 years since beginning of its operation it was thought that the plant was aged with elapsing time even if not recognizing any indication on its aged deterioration at that time. Therefore, for its concrete countermeasure, by supposing long-term operation of a plant with longer operation history, some technical evaluation on aged phenomena were carried out, to investigate on reflection of the obtained results to present conservation actions. Here were described on efforts on the high aging countermeasures, and performing conditions of long-term conservation in the Tsuruga Unit No. 1 Nuclear Power Station. (G.K.)

  16. Susceptibility and resilience to memory aging stereotypes: education matters more than age.

    Science.gov (United States)

    Andreoletti, Carrie; Lachman, Margie E

    2004-01-01

    The authors examined whether the memory performance of young, middle-aged, and older adults would be influenced by stereotype versus counterstereotype information about age differences on a memory task. One hundred forty-nine adults from a probability sample were randomly assigned to a control group or to age-stereotype conditions. As predicted, counterstereotype information was related to higher recall compared to stereotype and control groups. This was true across all age groups, but only for those with more education. Both stereotype and counterstereotype information were related to lower recall compared to the control group across age groups for those with lower education. Results suggest those with more education are more resilient when faced with negative age stereotypes about memory and respond positively to counterstereotype information. In contrast, those with less education show greater susceptibility to the detrimental effects of age stereotypes and respond negatively to both stereotype and counterstereotype information about memory aging.

  17. Negative probability in the framework of combined probability

    OpenAIRE

    Burgin, Mark

    2013-01-01

    Negative probability has found diverse applications in theoretical physics. Thus, construction of sound and rigorous mathematical foundations for negative probability is important for physics. There are different axiomatizations of conventional probability. So, it is natural that negative probability also has different axiomatic frameworks. In the previous publications (Burgin, 2009; 2010), negative probability was mathematically formalized and rigorously interpreted in the context of extende...

  18. Probability of Survival Decision Aid (PSDA)

    National Research Council Canada - National Science Library

    Xu, Xiaojiang; Amin, Mitesh; Santee, William R

    2008-01-01

    A Probability of Survival Decision Aid (PSDA) is developed to predict survival time for hypothermia and dehydration during prolonged exposure at sea in both air and water for a wide range of environmental conditions...

  19. Random phenomena fundamentals of probability and statistics for engineers

    CERN Document Server

    Ogunnaike, Babatunde A

    2009-01-01

    PreludeApproach PhilosophyFour Basic PrinciplesI FoundationsTwo Motivating ExamplesYield Improvement in a Chemical ProcessQuality Assurance in a Glass Sheet Manufacturing ProcessOutline of a Systematic ApproachRandom Phenomena, Variability, and UncertaintyTwo Extreme Idealizations of Natural PhenomenaRandom Mass PhenomenaIntroducing ProbabilityThe Probabilistic FrameworkII ProbabilityFundamentals of Probability TheoryBuilding BlocksOperationsProbabilityConditional ProbabilityIndependenceRandom Variables and DistributionsDistributionsMathematical ExpectationCharacterizing DistributionsSpecial Derived Probability FunctionsMultidimensional Random VariablesDistributions of Several Random VariablesDistributional Characteristics of Jointly Distributed Random VariablesRandom Variable TransformationsSingle Variable TransformationsBivariate TransformationsGeneral Multivariate TransformationsApplication Case Studies I: ProbabilityMendel and HeredityWorld War II Warship Tactical Response Under AttackIII DistributionsIde...

  20. Effect of Age, Hair Type and Body Condition Score on Body ...

    African Journals Online (AJOL)

    The study was conducted to determine the influence of age, hair type and body condition score on body weight and body conformation traits using 62 Yankasa rams. The ages of the rams were categorized into three; 12-18, 19-24 and 25-36 months. The hair types which were determined through touching and feeling were ...

  1. Quantum probabilities of composite events in quantum measurements with multimode states

    International Nuclear Information System (INIS)

    Yukalov, V I; Sornette, D

    2013-01-01

    The problem of defining quantum probabilities of composite events is considered. This problem is of great importance for the theory of quantum measurements and for quantum decision theory, which is a part of measurement theory. We show that the Lüders probability of consecutive measurements is a transition probability between two quantum states and that this probability cannot be treated as a quantum extension of the classical conditional probability. The Wigner distribution is shown to be a weighted transition probability that cannot be accepted as a quantum extension of the classical joint probability. We suggest the definition of quantum joint probabilities by introducing composite events in multichannel measurements. The notion of measurements under uncertainty is defined. We demonstrate that the necessary condition for mode interference is the entanglement of the composite prospect together with the entanglement of the composite statistical state. As an illustration, we consider an example of a quantum game. Special attention is paid to the application of the approach to systems with multimode states, such as atoms, molecules, quantum dots, or trapped Bose-condensed atoms with several coherent modes. (paper)

  2. Conditional Genealogies and the Age of a Neutral Mutant

    DEFF Research Database (Denmark)

    Wiuf, Carsten; Donelly, P

    1999-01-01

    This paper is concerned with the structure of the genealogy of a sample in which it is observed that some subset of chromosomes carries a particular mutation, assumed to have arisen uniquely in the history of the population. A rigorous theoretical study of this conditional genealogy is given using...... coalescent methods. Particular results include the mean, variance, and density of the age of the mutation conditional on its frequency in the sample. Most of the development relates to populations of constant size, but we discuss the extension to populations which have grown exponentially to their present...

  3. Tools and techniques for ageing predictions in nuclear reactors through condition monitoring

    International Nuclear Information System (INIS)

    Verma, R.M.P.

    1994-01-01

    To operate the nuclear reactors beyond their design predicted life is gaining importance because of huge replacement and decommissioning costs. But experience shows that nuclear plant safety and reliability may decline in the later years of plant life due to ageing degradation. Ageing of nuclear plant components, structures and systems, if unmitigated reduces their safety margins provided in the design and thus increases risks to public health and safety. These safety margins must be monitored throughout plant service life including any extended life. Condition monitoring of nuclear reactor components/equipment and systems can be done to study the effect of ageing, status of safety margins and effect of corrective and mitigating actions taken. The tools and techniques of condition monitoring are also important in failure trending, predictive maintenance, evaluation of scheduled maintenance, in mitigation of ageing, life extension and reliability studies. (author). 1 fig., 1 annexure

  4. Crosslinking of SAVY-4000 O-rings as a Function of Aging Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Van Buskirk, Caleb Griffith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-08

    SAVY-4000 containers were developed as a part of DOE M 441.1-1 to protect workers who handle stored nuclear material from exposure due to loss of containment.1 The SAVY-4000 is comprised of three parts: a lid, a container, and a cross-linked fluoropolymer O-ring. Degradation of the O-ring during use could limit the lifetime of the SAVY-4000. In order to quantify the chemical changes of the Oring over time, the molecular weight between crosslinks was determined as a function of aging conditions using a swelling technique. Because the O-ring is a cross-linked polymer, it will absorb solvent into its matrix without dissolving. The relative amount of solvent uptake can be related to the degree of crosslinking using an equation developed by Paul Flory and John Rehner Jr3. This method was used to analyze O-ring samples aged under thermal and ionizing-radiation conditions. It was found that at the harsher thermal gaining conditions in absence of ionizing-radiation the average molecular weight between crosslinks decreased, indicating a rise in crosslinks, which may be attributable to advanced aging with no ionizing radiation present. Inversely, in the presence of ionizing radiation it was found that material has a higher level of cross-linking with age. This information could be used to help predict the lifetime of the O-rings in SAVY-4000 containers under service conditions.

  5. Eruption probabilities for the Lassen Volcanic Center and regional volcanism, northern California, and probabilities for large explosive eruptions in the Cascade Range

    Science.gov (United States)

    Nathenson, Manuel; Clynne, Michael A.; Muffler, L.J. Patrick

    2012-01-01

    Chronologies for eruptive activity of the Lassen Volcanic Center and for eruptions from the regional mafic vents in the surrounding area of the Lassen segment of the Cascade Range are here used to estimate probabilities of future eruptions. For the regional mafic volcanism, the ages of many vents are known only within broad ranges, and two models are developed that should bracket the actual eruptive ages. These chronologies are used with exponential, Weibull, and mixed-exponential probability distributions to match the data for time intervals between eruptions. For the Lassen Volcanic Center, the probability of an eruption in the next year is 1.4x10-4 for the exponential distribution and 2.3x10-4 for the mixed exponential distribution. For the regional mafic vents, the exponential distribution gives a probability of an eruption in the next year of 6.5x10-4, but the mixed exponential distribution indicates that the current probability, 12,000 years after the last event, could be significantly lower. For the exponential distribution, the highest probability is for an eruption from a regional mafic vent. Data on areas and volumes of lava flows and domes of the Lassen Volcanic Center and of eruptions from the regional mafic vents provide constraints on the probable sizes of future eruptions. Probabilities of lava-flow coverage are similar for the Lassen Volcanic Center and for regional mafic vents, whereas the probable eruptive volumes for the mafic vents are generally smaller. Data have been compiled for large explosive eruptions (>≈ 5 km3 in deposit volume) in the Cascade Range during the past 1.2 m.y. in order to estimate probabilities of eruption. For erupted volumes >≈5 km3, the rate of occurrence since 13.6 ka is much higher than for the entire period, and we use these data to calculate the annual probability of a large eruption at 4.6x10-4. For erupted volumes ≥10 km3, the rate of occurrence has been reasonably constant from 630 ka to the present, giving

  6. Effects of artificial aging conditions on yttria-stabilized zirconia implant abutments.

    Science.gov (United States)

    Basílio, Mariana de Almeida; Cardoso, Kátia Vieira; Antonio, Selma Gutierrez; Rizkalla, Amin Sami; Santos Junior, Gildo Coelho; Arioli Filho, João Neudenir

    2016-08-01

    Most ceramic abutments are fabricated from yttria-stabilized tetragonal zirconia (Y-TZP). However, Y-TZP undergoes hydrothermal degradation, a process that is not well understood. The purpose of this in vitro study was to assess the effects of artificial aging conditions on the fracture load, phase stability, and surface microstructure of a Y-TZP abutment. Thirty-two prefabricated Y-TZP abutments were screwed and tightened down to external hexagon implants and divided into 4 groups (n = 8): C, control; MC, mechanical cycling (1×10(6) cycles; 10 Hz); AUT, autoclaving (134°C; 5 hours; 0.2 MPa); and TC, thermal cycling (10(4) cycles; 5°/55°C). A single-load-to-fracture test was performed at a crosshead speed of 0.5 mm/min to assess the assembly's resistance to fracture (ISO Norm 14801). X-ray diffraction (XRD) analysis was applied to observe and quantify the tetragonal-monoclinic (t-m) phase transformation. Representative abutments were examined with high-resolution scanning electron microscopy (SEM) to observe the surface characteristics of the abutments. Load-to-fracture test results (N) were compared by ANOVA and Tukey test (α=.05). XRD measurements revealed the monoclinic phase in some abutments after each aging condition. All the aging conditions reduced the fracture load significantly (Paging conditions. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  7. Enhanced taurine release in cell-damaging conditions in the developing and ageing mouse hippocampus.

    Science.gov (United States)

    Saransaari, P; Oja, S S

    1997-08-01

    Taurine has been shown to be essential for neuronal development and survival in the central nervous system. The release of preloaded [3H]taurine was studied in hippocampal slices from seven-day-, three-month- and 18-22-month-old mice in cell-damaging conditions. The slices were superfused in hypoxic, hypoglycemic and ischemic conditions and exposed to free radicals and oxidative stress. The release of taurine was greatly enhanced in the above conditions in all age groups, except in oxidative stress. The release was large in ischemia, particularly in the hippocampus of aged mice. Potassium stimulation was still able to release taurine in cell-damaging conditions in immature mice, whereas in adult and aged animals the release was so substantial that this additional stimulus failed to work. Taurine release was partially Ca2+-dependent in all cases. The massive release of the inhibitory amino acid taurine in ischemic conditions could act neuroprotectively, counteracting in several ways the effects of simultaneous release of excitatory amino acids. This protection could be of great importance in developing brain tissue, while also having an effect in aged brains.

  8. Performance in eyeblink conditioning is age and sex dependent.

    Directory of Open Access Journals (Sweden)

    Karolina Löwgren

    Full Text Available A growing body of evidence suggests that the cerebellum is involved in both cognition and language. Abnormal cerebellar development may contribute to neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD, autism, fetal alcohol syndrome, dyslexia, and specific language impairment. Performance in eyeblink conditioning, which depends on the cerebellum, can potentially be used to clarify the neural mechanisms underlying the cerebellar dysfunction in disorders like these. However, we must first understand how the performance develops in children who do not have a disorder. In this study we assessed the performance in eyeblink conditioning in 42 typically developing children between 6 and 11 years old as well as in 26 adults. Older children produced more conditioned eyeblink responses than younger children and adults produced more than children. In addition, females produced more conditioned eyeblink responses than males among both children and adults. These results highlight the importance of considering the influence of age and sex on the performance when studying eyeblink conditioning as a measure of cerebellar development.

  9. Multiple-event probability in general-relativistic quantum mechanics

    International Nuclear Information System (INIS)

    Hellmann, Frank; Mondragon, Mauricio; Perez, Alejandro; Rovelli, Carlo

    2007-01-01

    We discuss the definition of quantum probability in the context of 'timeless' general-relativistic quantum mechanics. In particular, we study the probability of sequences of events, or multievent probability. In conventional quantum mechanics this can be obtained by means of the 'wave function collapse' algorithm. We first point out certain difficulties of some natural definitions of multievent probability, including the conditional probability widely considered in the literature. We then observe that multievent probability can be reduced to single-event probability, by taking into account the quantum nature of the measuring apparatus. In fact, by exploiting the von-Neumann freedom of moving the quantum/classical boundary, one can always trade a sequence of noncommuting quantum measurements at different times, with an ensemble of simultaneous commuting measurements on the joint system+apparatus system. This observation permits a formulation of quantum theory based only on single-event probability, where the results of the wave function collapse algorithm can nevertheless be recovered. The discussion also bears on the nature of the quantum collapse

  10. Stereotypes Associated With Age-related Conditions and Assistive Device Use in Canadian Media.

    Science.gov (United States)

    Fraser, Sarah Anne; Kenyon, Virginia; Lagacé, Martine; Wittich, Walter; Southall, Kenneth Edmund

    2016-12-01

    Newspapers are an important source of information. The discourses within the media can influence public attitudes and support or discourage stereotypical portrayals of older individuals. This study critically examined discourses within a Canadian newspaper in terms of stereotypical depictions of age-related health conditions and assistive technology devices (ATDs). Four years (2009-2013) of Globe and Mail articles were searched for terms relevant to the research question. A total of 65 articles were retained, and a critical discourse analysis (CDA) of the texts was conducted. The articles were coded for stereotypes associated with age-related health conditions and ATDs, consequences of the stereotyping, and context (overall setting or background) of the discourse. The primary code list included 4 contexts, 13 stereotypes, and 9 consequences of stereotyping. CDA revealed discourses relating to (a) maintaining autonomy in a stereotypical world, (b) ATDs as obstacles in employment, (c) barriers to help seeking for age-related conditions, and (d) people in power setting the stage for discrimination. Our findings indicate that discourses in the Canadian media include stereotypes associated with age-related health conditions. Further, depictions of health conditions and ATDs may exacerbate existing stereotypes about older individuals, limit the options available to them, lead to a reduction in help seeking, and lower ATD use. Education about the realities of age-related health changes and ATDs is needed in order to diminish stereotypes and encourage ATD uptake and use. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Single, Complete, Probability Spaces Consistent With EPR-Bohm-Bell Experimental Data

    Science.gov (United States)

    Avis, David; Fischer, Paul; Hilbert, Astrid; Khrennikov, Andrei

    2009-03-01

    We show that paradoxical consequences of violations of Bell's inequality are induced by the use of an unsuitable probabilistic description for the EPR-Bohm-Bell experiment. The conventional description (due to Bell) is based on a combination of statistical data collected for different settings of polarization beam splitters (PBSs). In fact, such data consists of some conditional probabilities which only partially define a probability space. Ignoring this conditioning leads to apparent contradictions in the classical probabilistic model (due to Kolmogorov). We show how to make a completely consistent probabilistic model by taking into account the probabilities of selecting the settings of the PBSs. Our model matches both the experimental data and is consistent with classical probability theory.

  12. Probability

    CERN Document Server

    Shiryaev, A N

    1996-01-01

    This book contains a systematic treatment of probability from the ground up, starting with intuitive ideas and gradually developing more sophisticated subjects, such as random walks, martingales, Markov chains, ergodic theory, weak convergence of probability measures, stationary stochastic processes, and the Kalman-Bucy filter Many examples are discussed in detail, and there are a large number of exercises The book is accessible to advanced undergraduates and can be used as a text for self-study This new edition contains substantial revisions and updated references The reader will find a deeper study of topics such as the distance between probability measures, metrization of weak convergence, and contiguity of probability measures Proofs for a number of some important results which were merely stated in the first edition have been added The author included new material on the probability of large deviations, and on the central limit theorem for sums of dependent random variables

  13. Internal Medicine residents use heuristics to estimate disease probability

    OpenAIRE

    Phang, Sen Han; Ravani, Pietro; Schaefer, Jeffrey; Wright, Bruce; McLaughlin, Kevin

    2015-01-01

    Background: Training in Bayesian reasoning may have limited impact on accuracy of probability estimates. In this study, our goal was to explore whether residents previously exposed to Bayesian reasoning use heuristics rather than Bayesian reasoning to estimate disease probabilities. We predicted that if residents use heuristics then post-test probability estimates would be increased by non-discriminating clinical features or a high anchor for a target condition. Method: We randomized 55 In...

  14. Upper Bounds for Ruin Probability with Stochastic Investment Return

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lihong

    2005-01-01

    Risk models with stochastic investment return are widely held in practice, as well as in more challenging research fields. Risk theory is mainly concerned with ruin probability, and a tight bound for ruin probability is the best for practical use. This paper presents a discrete time risk model with stochastic investment return. Conditional expectation properties and martingale inequalities are used to obtain both exponential and non-exponential upper bounds for the ruin probability.

  15. A Novel Adaptive Conditional Probability-Based Predicting Model for User’s Personality Traits

    Directory of Open Access Journals (Sweden)

    Mengmeng Wang

    2015-01-01

    Full Text Available With the pervasive increase in social media use, the explosion of users’ generated data provides a potentially very rich source of information, which plays an important role in helping online researchers understand user’s behaviors deeply. Since user’s personality traits are the driving force of user’s behaviors, hence, in this paper, along with social network features, we first extract linguistic features, emotional statistical features, and topic features from user’s Facebook status updates, followed by quantifying importance of features via Kendall correlation coefficient. And then, on the basis of weighted features and dynamic updated thresholds of personality traits, we deploy a novel adaptive conditional probability-based predicting model which considers prior knowledge of correlations between user’s personality traits to predict user’s Big Five personality traits. In the experimental work, we explore the existence of correlations between user’s personality traits which provides a better theoretical support for our proposed method. Moreover, on the same Facebook dataset, compared to other methods, our method can achieve an F1-measure of 80.6% when taking into account correlations between user’s personality traits, and there is an impressive improvement of 5.8% over other approaches.

  16. Wire system aging assessment and condition monitoring (WASCO)

    International Nuclear Information System (INIS)

    Fantoni, P.F.; Nordlund, A.

    2006-04-01

    Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report describes a method for wire system condition monitoring, developed at the Halden Reactor Project, which is based on Frequency Domain Reflectometry. This method resulted in the development of a system called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. LIRA is composed of a signal generator, a signal analyser and a simulator that can be used to simulate several failure/degradation scenarios and assess the accuracy and sensitivity of the LIRA system. Chapter 5 of this report describes an complementary approach based on positron measurement techniques, used widely in defect physics due to the high sensitivity to micro defects, in particular open volume defects. This report describes in details these methodologies, the results of field experiments and the proposed future work. (au)

  17. Wire system aging assessment and condition monitoring (WASCO)

    Energy Technology Data Exchange (ETDEWEB)

    Fantoni, P.F. [Institutt for energiteknikk (Norway); Nordlund, A. [Chalmers Univ. of Technology (Sweden)

    2006-04-15

    Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. Condition Monitoring (CM) of installed wire systems is an important part of any aging program, both during the first 40 years of the qualified life and even more in anticipation of the license renewal for a nuclear power plant. This report describes a method for wire system condition monitoring, developed at the Halden Reactor Project, which is based on Frequency Domain Reflectometry. This method resulted in the development of a system called LIRA (LIne Resonance Analysis), which can be used on-line to detect any local or global changes in the cable electrical parameters as a consequence of insulation faults or degradation. LIRA is composed of a signal generator, a signal analyser and a simulator that can be used to simulate several failure/degradation scenarios and assess the accuracy and sensitivity of the LIRA system. Chapter 5 of this report describes an complementary approach based on positron measurement techniques, used widely in defect physics due to the high sensitivity to micro defects, in particular open volume defects. This report describes in details these methodologies, the results of field experiments and the proposed future work. (au)

  18. Estimation of functional failure probability of passive systems based on subset simulation method

    International Nuclear Information System (INIS)

    Wang Dongqing; Wang Baosheng; Zhang Jianmin; Jiang Jing

    2012-01-01

    In order to solve the problem of multi-dimensional epistemic uncertainties and small functional failure probability of passive systems, an innovative reliability analysis algorithm called subset simulation based on Markov chain Monte Carlo was presented. The method is found on the idea that a small failure probability can be expressed as a product of larger conditional failure probabilities by introducing a proper choice of intermediate failure events. Markov chain Monte Carlo simulation was implemented to efficiently generate conditional samples for estimating the conditional failure probabilities. Taking the AP1000 passive residual heat removal system, for example, the uncertainties related to the model of a passive system and the numerical values of its input parameters were considered in this paper. And then the probability of functional failure was estimated with subset simulation method. The numerical results demonstrate that subset simulation method has the high computing efficiency and excellent computing accuracy compared with traditional probability analysis methods. (authors)

  19. Left passage probability of Schramm-Loewner Evolution

    Science.gov (United States)

    Najafi, M. N.

    2013-06-01

    SLE(κ,ρ⃗) is a variant of Schramm-Loewner Evolution (SLE) which describes the curves which are not conformal invariant, but are self-similar due to the presence of some other preferred points on the boundary. In this paper we study the left passage probability (LPP) of SLE(κ,ρ⃗) through field theoretical framework and find the differential equation governing this probability. This equation is numerically solved for the special case κ=2 and hρ=0 in which hρ is the conformal weight of the boundary changing (bcc) operator. It may be referred to loop erased random walk (LERW) and Abelian sandpile model (ASM) with a sink on its boundary. For the curve which starts from ξ0 and conditioned by a change of boundary conditions at x0, we find that this probability depends significantly on the factor x0-ξ0. We also present the perturbative general solution for large x0. As a prototype, we apply this formalism to SLE(κ,κ-6) which governs the curves that start from and end on the real axis.

  20. Estimation of post-test probabilities by residents: Bayesian reasoning versus heuristics?

    Science.gov (United States)

    Hall, Stacey; Phang, Sen Han; Schaefer, Jeffrey P; Ghali, William; Wright, Bruce; McLaughlin, Kevin

    2014-08-01

    Although the process of diagnosing invariably begins with a heuristic, we encourage our learners to support their diagnoses by analytical cognitive processes, such as Bayesian reasoning, in an attempt to mitigate the effects of heuristics on diagnosing. There are, however, limited data on the use ± impact of Bayesian reasoning on the accuracy of disease probability estimates. In this study our objective was to explore whether Internal Medicine residents use a Bayesian process to estimate disease probabilities by comparing their disease probability estimates to literature-derived Bayesian post-test probabilities. We gave 35 Internal Medicine residents four clinical vignettes in the form of a referral letter and asked them to estimate the post-test probability of the target condition in each case. We then compared these to literature-derived probabilities. For each vignette the estimated probability was significantly different from the literature-derived probability. For the two cases with low literature-derived probability our participants significantly overestimated the probability of these target conditions being the correct diagnosis, whereas for the two cases with high literature-derived probability the estimated probability was significantly lower than the calculated value. Our results suggest that residents generate inaccurate post-test probability estimates. Possible explanations for this include ineffective application of Bayesian reasoning, attribute substitution whereby a complex cognitive task is replaced by an easier one (e.g., a heuristic), or systematic rater bias, such as central tendency bias. Further studies are needed to identify the reasons for inaccuracy of disease probability estimates and to explore ways of improving accuracy.

  1. Conditioned pain modulation (CPM) in children and adolescents: Effects of sex and age

    Science.gov (United States)

    Tsao, Jennie C. I.; Seidman, Laura C.; Evans, Subhadra; Lung, Kirsten C.; Zeltzer, Lonnie K.; Naliboff, Bruce D.

    2013-01-01

    Conditioned pain modulation (CPM) refers to the diminution of perceived pain intensity for a test stimulus following application of a conditioning stimulus to a remote area of the body, and is thought to reflect the descending inhibition of nociceptive signals. Studying CPM in children may inform interventions to enhance central pain inhibition within a developmental framework. We assessed CPM in 133 healthy children (mean age = 13 years; 52.6% girls) and tested the effects of sex and age. Participants were exposed to four trials of a pressure test stimulus before, during, and after the application of a cold water conditioning stimulus. CPM was documented by a reduction in pressure pain ratings during cold water administration. Older children (12–17 years) exhibited greater CPM than younger (8–11 years) children. No sex differences in CPM were found. Lower heart rate variability (HRV) at baseline and after pain induction was associated with less CPM controlling for child age. The findings of greater CPM in the older age cohort suggest a developmental improvement in central pain inhibitory mechanisms. The results highlight the need to examine developmental and contributory factors in central pain inhibitory mechanisms in children to guide effective, age appropriate, pain interventions. PMID:23541066

  2. Influence of age on postural sway during different dual-task conditions.

    Directory of Open Access Journals (Sweden)

    Marco eBergamin

    2014-10-01

    Full Text Available Dual-task performance assessments of competing parallel tasks and postural outcomes are growing in importance for geriatricians, as it is associated with predicting fall risk in older adults. This study aims to evaluate the postural stability during different dual-task conditions including visual (SMBT, verbal (CBAT and cognitive (MAT tasks in comparison with the standard Romberg’s open eyes position (OE. Furthermore, these conditions were investigated in a sample of young adults and a group of older healthy subjects to examine a potential interaction between type of secondary task and age status. To compare these groups across the four conditions, a within-between mixed model ANOVA was applied. Thus, a stabilometric platform has been used to measure center of pressure velocity (CoPV, sway area (SA, antero-posterior (AP and medio-lateral (ML oscillations as extents of postural sway. Tests of within-subjects effects indicated that different four conditions influenced the static balance for CoPV (p<0.001, SA (p<0.001. Post-hoc analyses indicated that CBAT task induced the worst balance condition on CoPV and resulted in significantly worse scores than OE (-11.4%; p<0.05, SMBT (-17.8% p<0.01 and MAT (-17.8% p<0.01 conditions; the largest SA was found in OE, and it was statistically larger than SMBT (-27.0%, p<0.01 and MAT (-23.1%; p<0.01. The between-subjects analysis indicated a general lower balance control in the group of elderly subjects (CoPV p<0.001, SA p<0.002, while, the mixed model ANOVA did not detect any interaction effect between types of secondary task and groups in any parameters (CoPV p=0.154, SA p=0.125. Postural sway during dual-task assessments was also found to decrease with advancing age, however, no interactions between aging and types of secondary tasks were found. Overall, these results indicated that the secondary task which most influenced the length of sway path, as measured by postural stability was a simple verbal

  3. Targeting the probability versus cost of feared outcomes in public speaking anxiety.

    Science.gov (United States)

    Nelson, Elizabeth A; Deacon, Brett J; Lickel, James J; Sy, Jennifer T

    2010-04-01

    Cognitive-behavioral theory suggests that social phobia is maintained, in part, by overestimates of the probability and cost of negative social events. Indeed, empirically supported cognitive-behavioral treatments directly target these cognitive biases through the use of in vivo exposure or behavioral experiments. While cognitive-behavioral theories and treatment protocols emphasize the importance of targeting probability and cost biases in the reduction of social anxiety, few studies have examined specific techniques for reducing probability and cost bias, and thus the relative efficacy of exposure to the probability versus cost of negative social events is unknown. In the present study, 37 undergraduates with high public speaking anxiety were randomly assigned to a single-session intervention designed to reduce either the perceived probability or the perceived cost of negative outcomes associated with public speaking. Compared to participants in the probability treatment condition, those in the cost treatment condition demonstrated significantly greater improvement on measures of public speaking anxiety and cost estimates for negative social events. The superior efficacy of the cost treatment condition was mediated by greater treatment-related changes in social cost estimates. The clinical implications of these findings are discussed. Published by Elsevier Ltd.

  4. The transition probability and the probability for the left-most particle's position of the q-totally asymmetric zero range process

    Energy Technology Data Exchange (ETDEWEB)

    Korhonen, Marko [Department of Mathematics and Statistics, University of Helsinki, FIN-00014 (Finland); Lee, Eunghyun [Centre de Recherches Mathématiques (CRM), Université de Montréal, Quebec H3C 3J7 (Canada)

    2014-01-15

    We treat the N-particle zero range process whose jumping rates satisfy a certain condition. This condition is required to use the Bethe ansatz and the resulting model is the q-boson model by Sasamoto and Wadati [“Exact results for one-dimensional totally asymmetric diffusion models,” J. Phys. A 31, 6057–6071 (1998)] or the q-totally asymmetric zero range process (TAZRP) by Borodin and Corwin [“Macdonald processes,” Probab. Theory Relat. Fields (to be published)]. We find the explicit formula of the transition probability of the q-TAZRP via the Bethe ansatz. By using the transition probability we find the probability distribution of the left-most particle's position at time t. To find the probability for the left-most particle's position we find a new identity corresponding to identity for the asymmetric simple exclusion process by Tracy and Widom [“Integral formulas for the asymmetric simple exclusion process,” Commun. Math. Phys. 279, 815–844 (2008)]. For the initial state that all particles occupy a single site, the probability distribution of the left-most particle's position at time t is represented by the contour integral of a determinant.

  5. Failure probability estimate of type 304 stainless steel piping

    International Nuclear Information System (INIS)

    Daugherty, W.L.; Awadalla, N.G.; Sindelar, R.L.; Mehta, H.S.; Ranganath, S.

    1989-01-01

    The primary source of in-service degradation of the SRS production reactor process water piping is intergranular stress corrosion cracking (IGSCC). IGSCC has occurred in a limited number of weld heat affected zones, areas known to be susceptible to IGSCC. A model has been developed to combine crack growth rates, crack size distributions, in-service examination reliability estimates and other considerations to estimate the pipe large-break frequency. This frequency estimates the probability that an IGSCC crack will initiate, escape detection by ultrasonic (UT) examination, and grow to instability prior to extending through-wall and being detected by the sensitive leak detection system. These events are combined as the product of four factors: (1) the probability that a given weld heat affected zone contains IGSCC; (2) the conditional probability, given the presence of IGSCC, that the cracking will escape detection during UT examination; (3) the conditional probability, given a crack escapes detection by UT, that it will not grow through-wall and be detected by leakage; (4) the conditional probability, given a crack is not detected by leakage, that it grows to instability prior to the next UT exam. These four factors estimate the occurrence of several conditions that must coexist in order for a crack to lead to a large break of the process water piping. When evaluated for the SRS production reactors, they produce an extremely low break frequency. The objective of this paper is to present the assumptions, methodology, results and conclusions of a probabilistic evaluation for the direct failure of the primary coolant piping resulting from normal operation and seismic loads. This evaluation was performed to support the ongoing PRA effort and to complement deterministic analyses addressing the credibility of a double-ended guillotine break

  6. Future southcentral US wildfire probability due to climate change

    Science.gov (United States)

    Stambaugh, Michael C.; Guyette, Richard P.; Stroh, Esther D.; Struckhoff, Matthew A.; Whittier, Joanna B.

    2018-01-01

    Globally, changing fire regimes due to climate is one of the greatest threats to ecosystems and society. In this paper, we present projections of future fire probability for the southcentral USA using downscaled climate projections and the Physical Chemistry Fire Frequency Model (PC2FM). Future fire probability is projected to both increase and decrease across the study region of Oklahoma, New Mexico, and Texas. Among all end-of-century projections, change in fire probabilities (CFPs) range from − 51 to + 240%. Greatest absolute increases in fire probability are shown for areas within the range of approximately 75 to 160 cm mean annual precipitation (MAP), regardless of climate model. Although fire is likely to become more frequent across the southcentral USA, spatial patterns may remain similar unless significant increases in precipitation occur, whereby more extensive areas with increased fire probability are predicted. Perhaps one of the most important results is illumination of climate changes where fire probability response (+, −) may deviate (i.e., tipping points). Fire regimes of southcentral US ecosystems occur in a geographic transition zone from reactant- to reaction-limited conditions, potentially making them uniquely responsive to different scenarios of temperature and precipitation changes. Identification and description of these conditions may help anticipate fire regime changes that will affect human health, agriculture, species conservation, and nutrient and water cycling.

  7. ELIPGRID-PC: A PC program for calculating hot spot probabilities

    International Nuclear Information System (INIS)

    Davidson, J.R.

    1994-10-01

    ELIPGRID-PC, a new personal computer program has been developed to provide easy access to Singer's 1972 ELIPGRID algorithm for hot-spot detection probabilities. Three features of the program are the ability to determine: (1) the grid size required for specified conditions, (2) the smallest hot spot that can be sampled with a given probability, and (3) the approximate grid size resulting from specified conditions and sampling cost. ELIPGRID-PC also provides probability of hit versus cost data for graphing with spread-sheets or graphics software. The program has been successfully tested using Singer's published ELIPGRID results. An apparent error in the original ELIPGRID code has been uncovered and an appropriate modification incorporated into the new program

  8. Leisure as a resource for successful aging by older adults with chronic health conditions.

    Science.gov (United States)

    Hutchinson, Susan L; Nimrod, Galit

    2012-01-01

    Drawing on the model of Selective Optimization with Compensation (SOC) (Baltes & Baltes, 1990), the purpose of this article is to examine leisure-related goals of older adults with chronic conditions and the strategies they use to not only successfully manage their chronic health conditions but live well with them. Semi-structured in-person interviews were conducted with 18 community-dwelling older adults (nine males, nine females, ages 58-87 years) with a variety of chronic conditions. Inductive and deductive within and cross-case thematic analyses resulted in descriptions of changes and continuity in participants' leisure participation following the onset of their chronic condition and construction of four themes: drawing on existing resources for continued involvement, setting leisure-based goals, using strategies to get more out of life, and more than managing: living a life of meaning. Implications for promoting successful aging are discussed, specifically the benefits of incorporating information and skill-building to help older adults recognize that leisure can be a resource for healthy aging and self-managing their chronic health condition.

  9. Quantum probability and quantum decision-making.

    Science.gov (United States)

    Yukalov, V I; Sornette, D

    2016-01-13

    A rigorous general definition of quantum probability is given, which is valid not only for elementary events but also for composite events, for operationally testable measurements as well as for inconclusive measurements, and also for non-commuting observables in addition to commutative observables. Our proposed definition of quantum probability makes it possible to describe quantum measurements and quantum decision-making on the same common mathematical footing. Conditions are formulated for the case when quantum decision theory reduces to its classical counterpart and for the situation where the use of quantum decision theory is necessary. © 2015 The Author(s).

  10. Quantifying seining detection probability for fishes of Great Plains sand‐bed rivers

    Science.gov (United States)

    Mollenhauer, Robert; Logue, Daniel R.; Brewer, Shannon K.

    2018-01-01

    Species detection error (i.e., imperfect and variable detection probability) is an essential consideration when investigators map distributions and interpret habitat associations. When fish detection error that is due to highly variable instream environments needs to be addressed, sand‐bed streams of the Great Plains represent a unique challenge. We quantified seining detection probability for diminutive Great Plains fishes across a range of sampling conditions in two sand‐bed rivers in Oklahoma. Imperfect detection resulted in underestimates of species occurrence using naïve estimates, particularly for less common fishes. Seining detection probability also varied among fishes and across sampling conditions. We observed a quadratic relationship between water depth and detection probability, in which the exact nature of the relationship was species‐specific and dependent on water clarity. Similarly, the direction of the relationship between water clarity and detection probability was species‐specific and dependent on differences in water depth. The relationship between water temperature and detection probability was also species dependent, where both the magnitude and direction of the relationship varied among fishes. We showed how ignoring detection error confounded an underlying relationship between species occurrence and water depth. Despite imperfect and heterogeneous detection, our results support that determining species absence can be accomplished with two to six spatially replicated seine hauls per 200‐m reach under average sampling conditions; however, required effort would be higher under certain conditions. Detection probability was low for the Arkansas River Shiner Notropis girardi, which is federally listed as threatened, and more than 10 seine hauls per 200‐m reach would be required to assess presence across sampling conditions. Our model allows scientists to estimate sampling effort to confidently assess species occurrence, which

  11. Probabilistic analysis of Millstone Unit 3 ultimate containment failure probability given high pressure: Chapter 14

    International Nuclear Information System (INIS)

    Bickel, J.H.

    1983-01-01

    The quantification of the containment event trees in the Millstone Unit 3 Probabilistic Safety Study utilizes a conditional probability of failure given high pressure which is based on a new approach. The generation of this conditional probability was based on a weakest link failure mode model which considered contributions from a number of overlapping failure modes. This overlap effect was due to a number of failure modes whose mean failure pressures were clustered within a 5 psi range and which had uncertainties due to variances in material strengths and analytical uncertainties which were between 9 and 15 psi. Based on a review of possible probability laws to describe the failure probability of individual structural failure modes, it was determined that a Weibull probability law most adequately described the randomness in the physical process of interest. The resultant conditional probability of failure is found to have a median failure pressure of 132.4 psia. The corresponding 5-95 percentile values are 112 psia and 146.7 psia respectively. The skewed nature of the conditional probability of failure vs. pressure results in a lower overall containment failure probability for an appreciable number of the severe accident sequences of interest, but also probabilities which are more rigorously traceable from first principles

  12. Scaling Qualitative Probability

    OpenAIRE

    Burgin, Mark

    2017-01-01

    There are different approaches to qualitative probability, which includes subjective probability. We developed a representation of qualitative probability based on relational systems, which allows modeling uncertainty by probability structures and is more coherent than existing approaches. This setting makes it possible proving that any comparative probability is induced by some probability structure (Theorem 2.1), that classical probability is a probability structure (Theorem 2.2) and that i...

  13. Age-related effects on postural control under multi-task conditions.

    Science.gov (United States)

    Granacher, Urs; Bridenbaugh, Stephanie A; Muehlbauer, Thomas; Wehrle, Anja; Kressig, Reto W

    2011-01-01

    Changes in postural sway and gait patterns due to simultaneously performed cognitive (CI) and/or motor interference (MI) tasks have previously been reported and are associated with an increased risk of falling in older adults. The objectives of this study were to investigate the effects of a CI and/or MI task on static and dynamic postural control in young and elderly subjects, and to find out whether there is an association between measures of static and dynamic postural control while concurrently performing the CI and/or MI task. A total of 36 healthy young (n = 18; age: 22.3 ± 3.0 years; BMI: 21.0 ± 1.6 kg/m(2)) and elderly adults (n = 18; age: 73.5 ± 5.5 years; BMI: 24.2 ± 2.9 kg/m(2)) participated in this study. Static postural control was measured during bipedal stance, and dynamic postural control was obtained while walking on an instrumented walkway. Irrespective of the task condition, i.e. single-task or multiple tasks, elderly participants showed larger center-of-pressure displacements and greater stride-to-stride variability than younger participants. Associations between measures of static and dynamic postural control were found only under the single-task condition in the elderly. Age-related deficits in the postural control system seem to be primarily responsible for the observed results. The weak correlations detected between static and dynamic measures could indicate that fall-risk assessment should incorporate dynamic measures under multi-task conditions, and that skills like erect standing and walking are independent of each other and may have to be trained complementarily. Copyright © 2010 S. Karger AG, Basel.

  14. Water Age Responses to Weather Conditions in a Hyper-Eutrophic Channel Reservoir in Southern China

    Directory of Open Access Journals (Sweden)

    Wei Du

    2016-08-01

    Full Text Available Channel reservoirs have the characteristics of both rivers and lakes, in which hydrodynamic conditions and the factors affecting the eutrophication process are complex and highly affected by weather conditions. Water age at any location in the reservoir is used as an indicator for describing the spatial and temporal variations of water exchange and nutrient transport. The hyper-eutrophic Changtan Reservoir (CTR in Southern China was investigated. Three weather conditions including wet, normal, and dry years were considered for assessing the response of water age by using the coupled watershed model Soil Water Assessment Tool (SWAT and the three-dimensional hydrodynamic model Environmental Fluid Hydrodynamic Code (EFDC. The results showed that the water age in CTR varied tremendously under different weather conditions. The averaged water ages at the downstream of CTR were 3 d, 60 d, and 110 d, respectively in the three typical wet, normal, and dry years. The highest water ages at the main tributary were >70 d, >100 d, and >200 d, respectively. The spatial distribution of water ages in the tributaries and the reservoir were mainly affected by precipitation. This paper provides useful information on water exchange and transport pathways in channel reservoir, which will be helpful in understanding nutrient dynamics for controlling algal blooms.

  15. Dementia in middle-aged patients with schizophrenia.

    Science.gov (United States)

    Nicolas, Gaël; Beherec, Laurène; Hannequin, Didier; Opolczynski, Gaëlle; Rothärmel, Maud; Wallon, David; Véra, Pierre; Martinaud, Olivier; Guillin, Olivier; Campion, Dominique

    2014-01-01

    Although numerous studies have assessed cognitive dysfunction in patients with schizophrenia, very few have focused on the diagnosis of dementia. Our objectives were to accurately diagnose dementia in a cohort of middle-aged patients with schizophrenia and to assess the type of dementia. 96 patients with schizophrenia (46 inpatients and 50 outpatients), aged 50 to 70 years, underwent a psychiatric, neurological, and neuropsychological evaluation at baseline and after a 20-month follow-up. We established a 3-step procedure: 1) diagnose dementia according to the DSM-IV criteria, using the Mattis Dementia Rating and Activities of Daily Living scales; 2) characterize dementia using brain imaging, perfusion by 99mTc-ECD-SPECT and laboratory tests including Alzheimer's disease cerebrospinal fluid biomarkers; and 3) search for genetic determinants. Fourteen patients fulfilled the diagnostic criteria of dementia. Four were diagnosed with possible or probable behavioral-variant frontotemporal dementia (bvFTD), two with probable Alzheimer's disease, two with probable vascular dementia (including one due to CADASIL), one with CNS inflammatory disease, and six could not be fully characterized. The diagnosis of dementia in middle-aged patients with schizophrenia is challenging but possible, using a multistep procedure. The most frequent condition, bvFTD, could reflect the presence of an evolutive neurodegenerative process in some patients.

  16. Age-dependent associations between telomere length and environmental conditions in roe deer.

    Science.gov (United States)

    Wilbourn, Rachael V; Froy, Hannah; McManus, Marie-Christina; Cheynel, Louise; Gaillard, Jean-Michel; Gilot-Fromont, Emmanuelle; Regis, Corinne; Rey, Benjamin; Pellerin, Maryline; Lemaître, Jean-François; Nussey, Daniel H

    2017-09-01

    Telomere length (TL) represents a promising biomarker of overall physiological state and of past environmental experiences, which could help us understand the drivers of life-history variation in natural populations. A growing number of studies in birds suggest that environmental stress or poor environmental conditions are associated with shortened TL, but studies of such relationships in wild mammals are lacking. Here, we compare leucocyte TL from cross-sectional samples collected from two French populations of roe deer which experience different environmental conditions. We found that, as predicted, TL was shorter in the population experiencing poor environmental conditions but that this difference was only significant in older individuals and was independent of sex and body mass. Unexpectedly, the difference was underpinned by a significant increase in TL with age in the population experiencing good environmental conditions, while there was no detectable relationship with age in poor conditions. These results demonstrate both the environmental sensitivity and complexity of telomere dynamics in natural mammal populations, and highlight the importance of longitudinal data to disentangle the within- and among-individual processes that generate them. © 2017 The Authors.

  17. Prognostic Value of Geriatric Conditions Beyond Age After Acute Coronary Syndrome.

    Science.gov (United States)

    Sanchis, Juan; Ruiz, Vicente; Bonanad, Clara; Valero, Ernesto; Ruescas-Nicolau, Maria Arantzazu; Ezzatvar, Yasmin; Sastre, Clara; García-Blas, Sergio; Mollar, Anna; Bertomeu-González, Vicente; Miñana, Gema; Núñez, Julio

    2017-06-01

    The aim of the present study was to investigate the prognostic value of geriatric conditions beyond age after acute coronary syndrome. This was a prospective cohort design including 342 patients (from October 1, 2010, to February 1, 2012) hospitalized for acute coronary syndrome, older than 65 years, in whom 5 geriatric conditions were evaluated at discharge: frailty (Fried and Green scales), comorbidity (Charlson and simple comorbidity indexes), cognitive impairment (Pfeiffer test), physical disability (Barthel index), and instrumental disability (Lawton-Brody scale). The primary end point was all-cause mortality. The median follow-up for the entire population was 4.7 years (range, 3-2178 days). A total of 156 patients (46%) died. Among the geriatric conditions, frailty (Green score, per point; hazard ratio, 1.11; 95% CI, 1.02-1.20; P=.01) and comorbidity (Charlson index, per point; hazard ratio, 1.18; 95% CI, 1.0-1.40; P=.05) were the independent predictors. The introduction of age in a basic model using well-established prognostic clinical variables resulted in an increase in discrimination accuracy (C-statistic=.716-.744; P=.05), though the addition of frailty and comorbidity provided a nonsignificant further increase (C-statistic=.759; P=.36). Likewise, the addition of age to the clinical model led to a significant risk reclassification (continuous net reclassification improvement, 0.46; 95% CI, 0.21-0.67; and integrated discrimination improvement, 0.04; 95% CI, 0.01-0.09). However, the addition of frailty and comorbidity provided a further significant risk reclassification in comparison to the clinical model with age (continuous net reclassification improvement, 0.40; 95% CI, 0.16-0.65; and integrated discrimination improvement, 0.04; 95% CI, 0.01-0.10). In conclusion, frailty and comorbidity are mortality predictors that significantly reclassify risk beyond age after acute coronary syndrome. Copyright © 2017 Mayo Foundation for Medical Education and

  18. Measurement uncertainty and probability

    CERN Document Server

    Willink, Robin

    2013-01-01

    A measurement result is incomplete without a statement of its 'uncertainty' or 'margin of error'. But what does this statement actually tell us? By examining the practical meaning of probability, this book discusses what is meant by a '95 percent interval of measurement uncertainty', and how such an interval can be calculated. The book argues that the concept of an unknown 'target value' is essential if probability is to be used as a tool for evaluating measurement uncertainty. It uses statistical concepts, such as a conditional confidence interval, to present 'extended' classical methods for evaluating measurement uncertainty. The use of the Monte Carlo principle for the simulation of experiments is described. Useful for researchers and graduate students, the book also discusses other philosophies relating to the evaluation of measurement uncertainty. It employs clear notation and language to avoid the confusion that exists in this controversial field of science.

  19. What Are Probability Surveys used by the National Aquatic Resource Surveys?

    Science.gov (United States)

    The National Aquatic Resource Surveys (NARS) use probability-survey designs to assess the condition of the nation’s waters. In probability surveys (also known as sample-surveys or statistical surveys), sampling sites are selected randomly.

  20. Long-Term Flexural Behaviors of GFRP Reinforced Concrete Beams Exposed to Accelerated Aging Exposure Conditions

    Directory of Open Access Journals (Sweden)

    Yeonho Park

    2014-06-01

    Full Text Available This study investigates the impact of accelerated aging conditions on the long-term flexural behavior and ductility of reinforced concrete (RC members with glass fiber-reinforced polymer (GFRP bars (RC-GFRP specimen and steel bars (RC-steel specimen. A total of thirty six specimens were designed with different amounts of reinforcement with three types of reinforcing bars (i.e., helically wrapped GFRP, sand-coated surface GFRP and steel. Eighteen specimens were subjected to sustained loads and accelerated aging conditions (i.e., 47 °C and 80% relative humidity in a chamber. The flexural behavior of specimens under 300-day exposure was compared to that of the companion specimens without experiencing accelerated aging conditions. Results indicate that the accelerated aging conditions reduced flexural capacity in not only RC-steel, but also RC-GFRP specimens, with different rates of reduction. Different types of GFRP reinforcement exhibited different rates of degradation of the flexural capacity when embedded in concrete under the same exposure conditions. Several existing models were compared with experimental results for predicting the deflection and deformability index for specimens. Bischoff and Gross’s model exhibited an excellent prediction of the time-dependent deflections. Except for the deformability index proposed by Jaeger, there was no general trend related to the aging duration. This study recommends the need for further investigation on the prediction of the deformability index.

  1. Occupational Safety and Health Conditions Aboard Small- and Medium-Size Fishing Vessels: Differences among Age Groups.

    Science.gov (United States)

    Zytoon, Mohamed A; Basahel, Abdulrahman M

    2017-02-24

    Although marine fishing is one of the most hazardous occupations, research on the occupational safety and health (OSH) conditions aboard marine fishing vessels is scarce. For instance, little is known about the working conditions of vulnerable groups such as young and aging fishermen. The objective of the current paper is to study the OSH conditions of young and aging fishermen compared to middle-aged fishermen in the small- and medium-size (SM) marine fishing sector. A cross-sectional study was designed, and 686 fishermen working aboard SM fishing vessels were interviewed to collect information about their safety and health. The associations of physical and psychosocial work conditions with safety and health outcomes, e.g., injuries, illnesses and job satisfaction, are presented. The results of the current study can be utilized in the design of effective accident prevention and OSH training programs for the three age groups and in the regulation of working conditions aboard fishing vessels.

  2. A quantum probability model of causal reasoning

    Directory of Open Access Journals (Sweden)

    Jennifer S Trueblood

    2012-05-01

    Full Text Available People can often outperform statistical methods and machine learning algorithms in situations that involve making inferences about the relationship between causes and effects. While people are remarkably good at causal reasoning in many situations, there are several instances where they deviate from expected responses. This paper examines three situations where judgments related to causal inference problems produce unexpected results and describes a quantum inference model based on the axiomatic principles of quantum probability theory that can explain these effects. Two of the three phenomena arise from the comparison of predictive judgments (i.e., the conditional probability of an effect given a cause with diagnostic judgments (i.e., the conditional probability of a cause given an effect. The third phenomenon is a new finding examining order effects in predictive causal judgments. The quantum inference model uses the notion of incompatibility among different causes to account for all three phenomena. Psychologically, the model assumes that individuals adopt different points of view when thinking about different causes. The model provides good fits to the data and offers a coherent account for all three causal reasoning effects thus proving to be a viable new candidate for modeling human judgment.

  3. Health Conditions and Passive Suicidal Ideation in the Survey of Health, Ageing, and Retirement in Europe

    Science.gov (United States)

    Morton, Kimberly; Turiano, Nicholas A.; Fiske, Amy

    2016-01-01

    Objectives: To examine the associations between health conditions and passive suicidal ideation in middle-aged and older adults. Method: Multivariate logistic regression analyses were conducted on data from 35,664 middle-aged and older adults from the Survey of Health, Ageing, and Retirement in Europe. Mediation analyses were also conducted to test the roles of disability and depression in risk of ideation. Results: After including demographic variables, disability, depression, and other health conditions as covariates, heart attack, diabetes/high blood sugar, chronic lung disease, arthritis, ulcer, and hip/femoral fractures were associated with increased odds of passive suicidal ideation. When grouped by organ systems, conditions affecting the endocrine, respiratory, and musculoskeletal systems were associated with increased odds of passive suicidal ideation, as was the total number of conditions. Individuals with greater numbers of health conditions exhibited greater levels of disability and depression, which partially explained the increased risk of passive suicidal ideation among those with more health conditions. Discussion: Certain specific health conditions, as well as total number of conditions, are associated with passive suicidal ideation in middle age and older adulthood. Health is a critical risk factor for suicidal ideation in late life and should be further studied in this particularly at-risk population. PMID:27013533

  4. Approximation of Measurement Results of “Emergency” Signal Reception Probability

    Directory of Open Access Journals (Sweden)

    Gajda Stanisław

    2017-08-01

    Full Text Available The intended aim of this article is to present approximation results of the exemplary measurements of EMERGENCY signal reception probability. The probability is under-stood as a distance function between the aircraft and a ground-based system under established conditions. The measurements were approximated using the properties of logistic functions. This probability, as a distance function, enables to determine the range of the EMERGENCY signal for a pre-set confidence level.

  5. Developmental Screening Using the Ages and Stages Questionnaire: Standardized versus Real-World Conditions

    Science.gov (United States)

    San Antonio, Marianne C.; Fenick, Ada M.; Shabanova, Veronika; Leventhal, John M.; Weitzman, Carol C.

    2014-01-01

    Developmental screens are often used in nonstandardized conditions, such as pediatric waiting rooms, despite validation under standardized conditions. We examined the reproducibility of the Ages and Stages Questionnaire (ASQ), a developmental screening instrument commonly used in pediatric practices, under standardized versus nonstandardized…

  6. ERPs, semantic processing and age.

    Science.gov (United States)

    Miyamoto, T; Katayama, J; Koyama, T

    1998-06-01

    ERPs (N400, LPC and CNV) were elicited in two sets of subjects grouped according to age (young vs. elderly) using a word-pair category matching paradigm. Each prime consisted of a Japanese noun (constructed from two to four characters of the Hiragana) followed by one Chinese character (Kanji) as the target, this latter representing one of five semantic categories. There were two equally probable target conditions: match or mismatch. Each target was preceded by a prime, either belonging to, or not belonging to, the same semantic category. The subjects were required to respond with a specified button press to the given target according to the condition. We found RTs to be longer in the elderly subjects and under the mismatch condition. N400 amplitude was reduced in the elderly subjects under the mismatch condition and there was no difference between match and mismatch response, which were similar in amplitude to that under match condition for the young subjects. In addition, the CNV amplitudes were larger in the elderly subjects. These results suggested that functional changes in semantic processing through aging (larger semantic networks and diffuse semantic activation) were the cause of this N400 reduction, attributing a subsidiary role to attentional disturbance. We also discuss the importance of taking age-related changes into consideration in clinical studies.

  7. Chronic health conditions and work ability in the ageing workforce : the impact of work conditions, psychosocial factors and perceived health

    NARCIS (Netherlands)

    Koolhaas, Wendy; van der Klink, Jac J. L.; de Boer, Michiel R.; Groothoff, Johan W.; Brouwer, Sandra

    The aim of this study was to determine the influence of work conditions, psychosocial factors and perceived health on the association between the presence of a chronic health condition and (single-item) work ability among workers aged 45 years and older. In addition, we aimed to examine variables

  8. Chronic health conditions and work ability in the ageing workforce: the impact of work conditions, psychosocial factors and perceived health

    NARCIS (Netherlands)

    Koolhaas, W.; van der Klink, J.J.L.; de Boer, M.R.; Groothoff, J.W.; Brouwer, S.

    2014-01-01

    Purpose: The aim of this study was to determine the influence of work conditions, psychosocial factors and perceived health on the association between the presence of a chronic health condition and (single-item) work ability among workers aged 45 years and older. In addition, we aimed to examine

  9. A probable new type of osteopenic bone disease

    Energy Technology Data Exchange (ETDEWEB)

    Widhe, Torulf L. [Department of Orthopaedics, Huddinge University Hospital (Sweden)

    2002-06-01

    A probable new type of osteopenic bone disease in two sisters and one female cousin is described. In infancy, the radiological findings were osteopenia, coxa vara, periosteal cloaking, bowing of the long bones, and flaring of the metaphyses. During growth, spinal pathology developed with compression of the vertebral bodies and scoliosis in one girl and kyphosis in another. All three children had genu valgum and two developed severe S-shaped bowing of the tibiae. Growth was stunted. Inheritance of this disorder is probably recessive. Type I and III collagen biosynthesis was normal. This condition is probably a hitherto undescribed form of osteogenesis imperfecta type III or a new bone disease. (orig.)

  10. A probable new type of osteopenic bone disease

    International Nuclear Information System (INIS)

    Widhe, Torulf L.

    2002-01-01

    A probable new type of osteopenic bone disease in two sisters and one female cousin is described. In infancy, the radiological findings were osteopenia, coxa vara, periosteal cloaking, bowing of the long bones, and flaring of the metaphyses. During growth, spinal pathology developed with compression of the vertebral bodies and scoliosis in one girl and kyphosis in another. All three children had genu valgum and two developed severe S-shaped bowing of the tibiae. Growth was stunted. Inheritance of this disorder is probably recessive. Type I and III collagen biosynthesis was normal. This condition is probably a hitherto undescribed form of osteogenesis imperfecta type III or a new bone disease. (orig.)

  11. Fasting: Benefits and probable health harmfulness from the Islamic perspective

    Directory of Open Access Journals (Sweden)

    Mahdi Ebrahimi

    2015-06-01

    Medical science can determine the effects and consequences of thirst and hunger during the month of Ramadan. In the religious perspective, it has been emphasized that fasting is for achieving the divine virtue, and this shouldn’t be in conflict with maintaining man’s health. Therefore, the conditions in which there is the probability of harmfulness to man’s health due to fasting, man shouldn’t fast. As a result, medical science could recognize the conditions in which there is probable harmfulness to man’s health.

  12. Age-dependent reliability model considering effects of maintenance and working conditions

    International Nuclear Information System (INIS)

    Martorell, Sebastian; Sanchez, Ana; Serradell, Vicente

    1999-01-01

    Nowadays, there is some doubt about building new nuclear power plants (NPPs). Instead, there is a growing interest in analyzing the possibility to extend current NPP operation, where life management programs play an important role. The evolution of the NPP safety depends on the evolution of the reliability of its safety components, which, in turn, is a function of their age along the NPP operational life. In this paper, a new age-dependent reliability model is presented, which includes parameters related to surveillance and maintenance effectiveness and working conditions of the equipment, both environmental and operational. This model may be used to support NPP life management and life extension programs, by improving or optimizing surveillance and maintenance tasks using risk and cost models based on such an age-dependent reliability model. The results of the sensitivity study in the example application show that the selection of the most appropriate maintenance strategy would directly depend on the previous parameters. Then, very important differences are expected to appear under certain circumstances, particularly, in comparison with other models that do not consider maintenance effectiveness and working conditions simultaneously

  13. Ageing model considering effects of maintenance and working conditions

    International Nuclear Information System (INIS)

    Martorell, S.; Sanchez, A.; Serradell, V.

    1998-01-01

    Nowadays, there is some doubt about building new Nuclear Power Plants (NPPs). Instead, there is a growing interest in analyzing the possibility to extend current NPP operation where life management programs play an important role. The evolution of the NPP safety depends on the evolution of the reliability of its safety components as a function of their age along the NPP operational life. In this paper, a new age-dependent reliability model is presented, which includes parameters related to surveillance and maintenance effectiveness and working conditions, both environmental and operational, of the equipment. This model may be used to support NPP life management and life extension programs by improving or optimizing surveillance and maintenance tasks using risk and cost models based on such an age-dependent reliability model. The results of the sensitivity study in the application show that the selection of the most appropriate maintenance strategy would directly depend on the previous parameters and very important differences are expected to appear under certain circumstance. (Author) 7 refs

  14. Changes in working conditions and physical health functioning among midlife and ageing employees.

    Science.gov (United States)

    Mänty, Minna; Kouvonen, Anne; Lallukka, Tea; Lahti, Jouni; Lahelma, Eero; Rahkonen, Ossi

    2015-11-01

    The aim this study was to examine the effect of changes in physical and psychosocial working conditions on physical health functioning among ageing municipal employees. Follow-up survey data were collected from midlife employees of the City of Helsinki, Finland, at three time points: wave 1 (2000-2002), wave 2 (2007), and wave 3 (2012). Changes in physical and psychosocial working conditions were assessed between waves 1 and 2. Physical health functioning was measured by the physical component summary (PCS) of the Short-Form 36 questionnaire at each of the three waves. In total, 2784 respondents (83% women) who remained employed over the follow-up were available for the analyses. Linear mixed-effect models were used to assess the associations and adjust for key covariates (age, gender, obesity, chronic diseases, and health behaviors). Repeated and increased exposure to adverse physical working conditions was associated with greater decline in physical health functioning over time. In contrast, decrease in exposures reduced the decline. Of the psychosocial working conditions, changes in job demands had no effects on physical health functioning. However, decreased job control was associated with greater decline and repeated high or increased job control reduced the decline in physical health functioning over time. Adverse changes in physical working conditions and job control were associated with greater decline in physical health functioning over time, whereas favorable changes in these exposures reduced the decline. Preventing deterioration and promoting improvement of working conditions are likely to help maintain better physical health functioning among ageing employees.

  15. The Efficacy of Using Diagrams When Solving Probability Word Problems in College

    Science.gov (United States)

    Beitzel, Brian D.; Staley, Richard K.

    2015-01-01

    Previous experiments have shown a deleterious effect of visual representations on college students' ability to solve total- and joint-probability word problems. The present experiments used conditional-probability problems, known to be more difficult than total- and joint-probability problems. The diagram group was instructed in how to use tree…

  16. Burden of high fracture probability worldwide: secular increases 2010-2040.

    Science.gov (United States)

    Odén, A; McCloskey, E V; Kanis, J A; Harvey, N C; Johansson, H

    2015-09-01

    The number of individuals aged 50 years or more at high risk of osteoporotic fracture worldwide in 2010 was estimated at 158 million and is set to double by 2040. The aim of this study was to quantify the number of individuals worldwide aged 50 years or more at high risk of osteoporotic fracture in 2010 and 2040. A threshold of high fracture probability was set at the age-specific 10-year probability of a major fracture (clinical vertebral, forearm, humeral or hip fracture) which was equivalent to that of a woman with a BMI of 24 kg/m(2) and a prior fragility fracture but no other clinical risk factors. The prevalence of high risk was determined worldwide and by continent using all available country-specific FRAX models and applied the population demography for each country. Twenty-one million men and 137 million women had a fracture probability at or above the threshold in the world for the year 2010. The greatest number of men and women at high risk were from Asia (55 %). Worldwide, the number of high-risk individuals is expected to double over the next 40 years. We conclude that individuals with high probability of osteoporotic fractures comprise a very significant disease burden to society, particularly in Asia, and that this burden is set to increase markedly in the future. These analyses provide a platform for the evaluation of risk assessment and intervention strategies.

  17. Introduction to probability and statistics for science, engineering, and finance

    CERN Document Server

    Rosenkrantz, Walter A

    2008-01-01

    Data Analysis Orientation The Role and Scope of Statistics in Science and Engineering Types of Data: Examples from Engineering, Public Health, and Finance The Frequency Distribution of a Variable Defined on a Population Quantiles of a Distribution Measures of Location (Central Value) and Variability Covariance, Correlation, and Regression: Computing a Stock's Beta Mathematical Details and Derivations Large Data Sets Probability Theory Orientation Sample Space, Events, Axioms of Probability Theory Mathematical Models of Random Sampling Conditional Probability and Baye

  18. Who in Europe Works beyond the State Pension Age and under which Conditions? Results from SHARE.

    Science.gov (United States)

    Wahrendorf, Morten; Akinwale, Bola; Landy, Rebecca; Matthews, Katey; Blane, David

    2017-01-01

    There is much research about those who exit the labour market prematurely, however, comparatively little is known about people working longer and about their employment and working conditions. In this paper, we describe the employment and working conditions of men and women working between 65 and 80 years, and compare them with previous conditions of those retired in the same age group. Analyses are based on wave 4 data from the Survey of Health, Ageing and Retirement in Europe (SHARE) with information collected between 2009 and 2011 from 17,625 older men and women across 16 European countries. Besides socio-demographic and health-related factors (physical and mental health), the focus lies on employment conditions (e.g. employment status, occupational position and working hours) and on stressful working conditions, measured in terms of low control at work and effort-reward imbalance. In case of retired people, information on working conditions refer to the last job before retirement. Following descriptive analyses, we then conduct multivariable analyses and investigate how working conditions and poor health are related to labour market participation (i.e. random intercept models accounting for country affiliation and adjusted for potential confounders). Results illustrate that people working between the ages of 65 and 80 are more likely to be self-employed (either with or without employees) and work in advantaged occupational positions. Furthermore, findings reveal that psychosocial working conditions are generally better than the conditions retired respondents had in their last job. Finally, in contrast to those who work, health tends to be worse among retired people. In conclusion, findings deliver empirical evidence that paid employment beyond age 65 is more common among self-employed workers throughout Europe, in advantaged occupations and under-favourable psychosocial circumstances, and that this group of workers are in considerably good mental and physical

  19. Quantum probability measures and tomographic probability densities

    NARCIS (Netherlands)

    Amosov, GG; Man'ko, [No Value

    2004-01-01

    Using a simple relation of the Dirac delta-function to generalized the theta-function, the relationship between the tomographic probability approach and the quantum probability measure approach with the description of quantum states is discussed. The quantum state tomogram expressed in terms of the

  20. Sexual behavior in the United States: results from a national probability sample of men and women ages 14-94.

    Science.gov (United States)

    Herbenick, Debby; Reece, Michael; Schick, Vanessa; Sanders, Stephanie A; Dodge, Brian; Fortenberry, J Dennis

    2010-10-01

    Despite a demonstrated relationship between sexual behaviors and health, including clinical risks, little is known about contemporary sexual behavior. To assess the rates of sexual behavior among adolescents and adults in the United States. We report the recent (past month, past year) and lifetime prevalence of sexual behaviors in a nationally representative probability sample of 5,865 men and women ages 14 to 94 in the United States (2,936 men, 2,929 women). Behaviors assessed included solo masturbation, partnered masturbation, giving and receiving oral sex, vaginal intercourse, and anal intercourse. Masturbation was common throughout the lifespan and more common than partnered sexual activities during adolescence and older age (70+). Although uncommon among 14- to 15-year olds, in the past year 18.3% of 16- to 17-year-old males and 22.4% of 16- to 17-year-old females performed oral sex with an other-sex partner. Also in the past year, more than half of women and men ages 18 to 49 engaged in oral sex. The proportion of adults who reported vaginal sex in the past year was highest among men ages 25-39 and for women ages 20-29, then progressively declined among older age groups. More than 20% of men ages 25-49 and women ages 20-39 reported anal sex in the past year. Same-sex sexual behaviors occurring in the past year were uncommonly reported. Men and women engage in a diverse range of solo and partnered sexual behaviors throughout the life course. The rates of contemporary sexual behavior provided in this report will be valuable to those who develop, implement, and evaluate programs that seek to improve societal knowledge related to the prevalence of sexual behaviors and to sexual health clinicians whose work to improve sexual health among the population often requires such rates of behavior. © 2010 International Society for Sexual Medicine.

  1. Crash probability estimation via quantifying driver hazard perception.

    Science.gov (United States)

    Li, Yang; Zheng, Yang; Wang, Jianqiang; Kodaka, Kenji; Li, Keqiang

    2018-07-01

    Crash probability estimation is an important method to predict the potential reduction of crash probability contributed by forward collision avoidance technologies (FCATs). In this study, we propose a practical approach to estimate crash probability, which combines a field operational test and numerical simulations of a typical rear-end crash model. To consider driver hazard perception characteristics, we define a novel hazard perception measure, called as driver risk response time, by considering both time-to-collision (TTC) and driver braking response to impending collision risk in a near-crash scenario. Also, we establish a driving database under mixed Chinese traffic conditions based on a CMBS (Collision Mitigation Braking Systems)-equipped vehicle. Applying the crash probability estimation in this database, we estimate the potential decrease in crash probability owing to use of CMBS. A comparison of the results with CMBS on and off shows a 13.7% reduction of crash probability in a typical rear-end near-crash scenario with a one-second delay of driver's braking response. These results indicate that CMBS is positive in collision prevention, especially in the case of inattentive drivers or ole drivers. The proposed crash probability estimation offers a practical way for evaluating the safety benefits in the design and testing of FCATs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Covariate-adjusted Spearman's rank correlation with probability-scale residuals.

    Science.gov (United States)

    Liu, Qi; Li, Chun; Wanga, Valentine; Shepherd, Bryan E

    2018-06-01

    It is desirable to adjust Spearman's rank correlation for covariates, yet existing approaches have limitations. For example, the traditionally defined partial Spearman's correlation does not have a sensible population parameter, and the conditional Spearman's correlation defined with copulas cannot be easily generalized to discrete variables. We define population parameters for both partial and conditional Spearman's correlation through concordance-discordance probabilities. The definitions are natural extensions of Spearman's rank correlation in the presence of covariates and are general for any orderable random variables. We show that they can be neatly expressed using probability-scale residuals (PSRs). This connection allows us to derive simple estimators. Our partial estimator for Spearman's correlation between X and Y adjusted for Z is the correlation of PSRs from models of X on Z and of Y on Z, which is analogous to the partial Pearson's correlation derived as the correlation of observed-minus-expected residuals. Our conditional estimator is the conditional correlation of PSRs. We describe estimation and inference, and highlight the use of semiparametric cumulative probability models, which allow preservation of the rank-based nature of Spearman's correlation. We conduct simulations to evaluate the performance of our estimators and compare them with other popular measures of association, demonstrating their robustness and efficiency. We illustrate our method in two applications, a biomarker study and a large survey. © 2017, The International Biometric Society.

  3. COVAL, Compound Probability Distribution for Function of Probability Distribution

    International Nuclear Information System (INIS)

    Astolfi, M.; Elbaz, J.

    1979-01-01

    1 - Nature of the physical problem solved: Computation of the probability distribution of a function of variables, given the probability distribution of the variables themselves. 'COVAL' has been applied to reliability analysis of a structure subject to random loads. 2 - Method of solution: Numerical transformation of probability distributions

  4. On Probability Leakage

    OpenAIRE

    Briggs, William M.

    2012-01-01

    The probability leakage of model M with respect to evidence E is defined. Probability leakage is a kind of model error. It occurs when M implies that events $y$, which are impossible given E, have positive probability. Leakage does not imply model falsification. Models with probability leakage cannot be calibrated empirically. Regression models, which are ubiquitous in statistical practice, often evince probability leakage.

  5. Prevalence of probable Attention-Deficit/Hyperactivity Disorder symptoms: result from a Spanish sample of children.

    Science.gov (United States)

    Cerrillo-Urbina, Alberto José; García-Hermoso, Antonio; Martínez-Vizcaíno, Vicente; Pardo-Guijarro, María Jesús; Ruiz-Hermosa, Abel; Sánchez-López, Mairena

    2018-03-15

    The aims of our study were to: (i) determine the prevalence of children aged 4 to 6 years with probable Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms in the Spanish population; and (ii) analyse the association of probable ADHD symptoms with sex, age, type of school, origin (native or foreign) and socio-economic status in these children. This cross-sectional study included 1189 children (4 to 6 years-old) from 21 primary schools in 19 towns from the Ciudad Real and Cuenca provinces, Castilla-La Mancha region, Spain. The ADHD Rating Scales IV for parents and teachers was administered to determine the probability of ADHD. The 90th percentile cut-off was used to establish the prevalence of inattention, hyperactivity/impulsivity and combined subtype. The prevalence of children with probable ADHD symptoms was 5.4% (2.6% inattention subtype symptoms, 1.5% hyperactivity/impulsivity subtype symptoms, and 1.3% combined subtype symptoms). Children aged 4 to 5 years showed a higher prevalence of probable ADHD in the inattention subtype symptoms and in total of all subtypes than children aged 6 years, and children with low socio-economic status reported a higher prevalence of probable ADHD symptoms (each subtype and total of all of them) than those with medium and high socio-economic status. Early diagnosis and an understanding of the predictors of being probable ADHD are needed to direct appropriate identification and intervention efforts. These screening efforts should be especially addressed to vulnerable groups, particularly low socio-economic status families and younger children.

  6. Transition probabilities of health states for workers in Malaysia using a Markov chain model

    Science.gov (United States)

    Samsuddin, Shamshimah; Ismail, Noriszura

    2017-04-01

    The aim of our study is to estimate the transition probabilities of health states for workers in Malaysia who contribute to the Employment Injury Scheme under the Social Security Organization Malaysia using the Markov chain model. Our study uses four states of health (active, temporary disability, permanent disability and death) based on the data collected from the longitudinal studies of workers in Malaysia for 5 years. The transition probabilities vary by health state, age and gender. The results show that men employees are more likely to have higher transition probabilities to any health state compared to women employees. The transition probabilities can be used to predict the future health of workers in terms of a function of current age, gender and health state.

  7. Chronic health conditions and work ability in the ageing workforce: the impact of work conditions, psychosocial factors and perceived health.

    Science.gov (United States)

    Koolhaas, Wendy; van der Klink, Jac J L; de Boer, Michiel R; Groothoff, Johan W; Brouwer, Sandra

    2014-05-01

    The aim of this study was to determine the influence of work conditions, psychosocial factors and perceived health on the association between the presence of a chronic health condition and (single-item) work ability among workers aged 45 years and older. In addition, we aimed to examine variables associated with work ability for workers with and without a chronic health condition separately. The data of this cross-sectional study were obtained from 5,247 workers aged 45 years and older in five different work sectors. Work ability was assessed with the first item of the Work Ability Index. The presence of a chronic health condition was assessed by self-report. Independent variables in the multivariable linear regression analysis were work conditions, psychosocial factors and perceived health status. The presence of a chronic health condition was negatively associated with work ability (B = -0.848). The strength of this association slightly attenuated after subsequently adding individual characteristics (B = -0.824), work conditions (B = -0.805) and more so after adding psychosocial factors (B = -0.704) and especially perceived health variables (B = -0.049) to the model. Variables associated with work ability for workers with and without a chronic health condition were similar. Perceived health and psychosocial factors, rather than work conditions, explained the association between the presence of a chronic health condition and work ability. Substantial differences in variables associated with work ability for workers with and without a chronic health condition were not found. Based on the lower mean scores for workers with a chronic health condition and work ability as well for predictors, these workers might have the most benefit by a policy focussing on enhancing these associated variables.

  8. Height probabilities in the Abelian sandpile model on the generalized finite Bethe lattice

    Science.gov (United States)

    Chen, Haiyan; Zhang, Fuji

    2013-08-01

    In this paper, we study the sandpile model on the generalized finite Bethe lattice with a particular boundary condition. Using a combinatorial method, we give the exact expressions for all single-site probabilities and some two-site joint probabilities. As a by-product, we prove that the height probabilities of bulk vertices are all the same for the Bethe lattice with certain given boundary condition, which was found from numerical evidence by Grassberger and Manna ["Some more sandpiles," J. Phys. (France) 51, 1077-1098 (1990)], 10.1051/jphys:0199000510110107700 but without a proof.

  9. Assessing the Relationship Between Chronic Health Conditions and Productivity Loss Trajectories

    Science.gov (United States)

    Pranksy, Glenn

    2014-01-01

    Objective: To examine the relationship between health conditions and the risk for membership in longitudinal trajectories of productivity loss. Methods: Trajectories of productivity loss from the ages of 25 to 44 years, previously identified in the National Longitudinal Survey of Youth (NLSY79), were combined with information on health conditions from the age 40 years health module in the NLSY79. Multinomial logistic regression was used to examine the relative risk of being in the low-risk, early-onset increasing risk, late-onset increasing risk, or high-risk trajectories compared with the no-risk trajectory for having various health conditions. Results: The trajectories with the greatest probability of productivity loss longitudinally had a greater prevalence of the individual health conditions and a greater total number of health conditions experienced. Conclusions: Health conditions are associated with specific longitudinal patterns of experiencing productivity loss. PMID:25479294

  10. Aging, condition monitoring, and loss-of-coolant accident (LOCA) tests of class 1E electrical cables

    International Nuclear Information System (INIS)

    Jacobus, M.J.

    1992-11-01

    This report describes the results of aging, condition monitoring, and accident testing of miscellaneous cable types. Three sets of cables were aged for up to 9 months under simultaneous thermal (≅100 degrees C) and radiation (≅0.10 kGy/hr) conditions. A sequential accident consisting of high dose rate irradiation (≅6 kGy/hr) and high temperature steam followed the aging. Also exposed to the accident conditions was a fourth set of cables, which were unaged. The test results indicate that, properly installed, most of the various miscellaneous cable products tested should be able to survive an accident after 60 years for total aging doses of at least 150 kGy or higher (depending on the material) and for moderate ambient temperatures on the order of 45--55 degrees C (potentially higher or lower, depending on material specific activtion energies and total radiation doses). Mechanical measurements (primarily elongation, modulus, and density) were more effective than electrical measurements for monitoring age-related degradation

  11. Influence of Aging Conditions on Fatigue Fracture Behaviour of 6063 Aluminum Alloy

    Directory of Open Access Journals (Sweden)

    Rafiq Ahmed Siddiqui

    2001-12-01

    Full Text Available Aluminum - Magnesium - Silicon (Al-Mg-Si 6063 alloy was heat-treated using under aged, peak aged and overage temperatures. The numbers of cycles required to cause the fatigue fracture, at constant stress, was considered as criteria for the fatigue resistance. Moreover, the fractured surface of the alloy at different aging conditions was evaluated by optical microscopy and the Scanning Electron Microscopy (SEM. The SEM micrographs confirmed the cleavage surfaces with well-defined fatigue striations. It has been observed that the various aging time and temperature of the 6063 Al-alloy, produces different modes of fractures. The most suitable age hardening time and temperature was found to be between 4 to 5 hours and to occur at 460 K. The increase in fatigue fracture property of the alloy due to aging could be attributed to a vacancy assisted diffusion mechanism or due to pinning of dislocations movement by the precipitates produced during aging. However, the decrease in the fatigue resistance, for the over aged alloys, might be due to the coalescence of precipitates into larger grains.

  12. Fitness prospects: effects of age, sex and recruitment age on reproductive value in a long-lived seabird.

    Science.gov (United States)

    Zhang, He; Rebke, Maren; Becker, Peter H; Bouwhuis, Sandra

    2015-01-01

    Reproductive value is an integrated measure of survival and reproduction fundamental to understanding life-history evolution and population dynamics, but little is known about intraspecific variation in reproductive value and factors explaining such variation, if any. By applying generalized additive mixed models to longitudinal individual-based data of the common tern Sterna hirundo, we estimated age-specific annual survival probability, breeding probability and reproductive performance, based on which we calculated age-specific reproductive values. We investigated effects of sex and recruitment age (RA) on each trait. We found age effects on all traits, with survival and breeding probability declining with age, while reproductive performance first improved with age before levelling off. We only found a very small, marginally significant, sex effect on survival probability, but evidence for decreasing age-specific breeding probability and reproductive performance with RA. As a result, males had slightly lower age-specific reproductive values than females, while birds of both sexes that recruited at the earliest ages of 2 and 3 years (i.e. 54% of the tern population) had somewhat higher fitness prospects than birds recruiting at later ages. While the RA effects on breeding probability and reproductive performance were statistically significant, these effects were not large enough to translate to significant effects on reproductive value. Age-specific reproductive values provided evidence for senescence, which came with fitness costs in a range of 17-21% for the sex-RA groups. Our study suggests that intraspecific variation in reproductive value may exist, but that, in the common tern, the differences are small. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  13. A Derivation of Probabilities of Correct and Wrongful Conviction in a Criminal Trial

    DEFF Research Database (Denmark)

    Lando, Henrik

    2006-01-01

    probabilities are the probability of observing (any given) evidence against individual i given that individual j committed the crime (for any j including j equal to i). The variables are derived from the conditional probabilities as a function of the standard of the proof using simple Bayesian updating....

  14. The probability of object-scene co-occurrence influences object identification processes.

    Science.gov (United States)

    Sauvé, Geneviève; Harmand, Mariane; Vanni, Léa; Brodeur, Mathieu B

    2017-07-01

    Contextual information allows the human brain to make predictions about the identity of objects that might be seen and irregularities between an object and its background slow down perception and identification processes. Bar and colleagues modeled the mechanisms underlying this beneficial effect suggesting that the brain stocks information about the statistical regularities of object and scene co-occurrence. Their model suggests that these recurring regularities could be conceptualized along a continuum in which the probability of seeing an object within a given scene can be high (probable condition), moderate (improbable condition) or null (impossible condition). In the present experiment, we propose to disentangle the electrophysiological correlates of these context effects by directly comparing object-scene pairs found along this continuum. We recorded the event-related potentials of 30 healthy participants (18-34 years old) and analyzed their brain activity in three time windows associated with context effects. We observed anterior negativities between 250 and 500 ms after object onset for the improbable and impossible conditions (improbable more negative than impossible) compared to the probable condition as well as a parieto-occipital positivity (improbable more positive than impossible). The brain may use different processing pathways to identify objects depending on whether the probability of co-occurrence with the scene is moderate (rely more on top-down effects) or null (rely more on bottom-up influences). The posterior positivity could index error monitoring aimed to ensure that no false information is integrated into mental representations of the world.

  15. MOD-AGE - an algorithm for age-depth model construction; U-series dated speleothems case study

    Science.gov (United States)

    Hercman, H.; Pawlak, J.

    2012-04-01

    We present MOD-AGE - a new system for chronology construction. MOD-AGE can be used for profiles that have been dated by different methods. As input data, the system uses the following basic measurements: activities, atomic ratios or age, as well as depth measurement. Based on probability distributions describing the measurement results, MOD-AGE estimates the age~depth relation and its confidence bands. To avoid the use of difficult-to-meet assumptions, MOD-AGE uses nonparametric methods. We applied a Monte Carlo simulation to model age and depth values based on the real distribution of counted data (activities, atomic ratios, depths etc.). Several fitting methods could be applied for estimating the relationships; based on several tests, we decide to use LOESS method (locally weighted scatterplot smoothing). The stratigraphic correction procedure applied in the MOD-AGE program uses a probability calculus, which assumes that the ages of all the samples are correctly estimated. Information about the probability distribution of the samples' ages is used to estimate the most probable sequence that is concordant according to the superposition rule. MOD-AGE is presented as a tool for the chronology construction of speleothems that have been analyzed by the U-series method, and it is compared to the StalAge algorithm presented by D. Scholtz and D.L Hoffmann (2011). Scholtz, D., Hoffmann, D. L., 2011. StalAge - An algorithm designed for construction of speleothem age models. Quaternary Geochronology 6, 369-382.

  16. Effect of in vitro aging on the flexural strength and probability to fracture of Y-TZP zirconia ceramics for all-ceramic restorations.

    Science.gov (United States)

    Siarampi, Eleni; Kontonasaki, Eleana; Andrikopoulos, Konstantinos S; Kantiranis, Nikolaos; Voyiatzis, George A; Zorba, Triantafillia; Paraskevopoulos, Konstantinos M; Koidis, Petros

    2014-12-01

    Dental zirconia restorations should present long-term clinical survival and be in service within the oral environment for many years. However, low temperature degradation could affect their mechanical properties and survival. The aim of this study was to investigate the effect of in vitro aging on the flexural strength of yttrium-stabilized (Y-TZP) zirconia ceramics for ceramic restorations. One hundred twenty bar-shaped specimens were prepared from two ceramics (ZENO Zr (WI) and IPS e.max(®) ZirCAD (IV)), and loaded until fracture according to ISO 6872. The specimens from each ceramic (nx=60) were divided in three groups (control, aged for 5h, aged for 10h). One-way ANOVA was used to assess statistically significant differences among flexural strength values (Pceramics, however statistically significant was for the WI group (Pceramics presented a t→m phase transformation, with the m-phase increasing from 4 to 5% at 5h to around 15% after 10h. The significant reduction of the flexural strength after 10h of in vitro aging, suggests high fracture probability for one of the zirconia ceramics tested. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  17. Age-dependent associations between androgenetic alopecia and prostate cancer risk.

    Science.gov (United States)

    Muller, David C; Giles, Graham G; Sinclair, Rod; Hopper, John L; English, Dallas R; Severi, Gianluca

    2013-02-01

    Both prostate cancer and androgenetic alopecia are strongly age-related conditions that are considered to be androgen dependent, but studies of the relationship between them have yielded inconsistent results. We aimed to assess whether androgenetic alopecia at ages 20 and 40 years are associated with risk of prostate cancer. At a follow-up of the Melbourne Collaborative Cohort Study, men were asked to assess their hair pattern at ages 20 and 40 years relative to eight categories in showcards. Cases were men notified to the Victorian Cancer Registry with prostate cancer diagnosed between cohort enrollment (1990-1994) and follow-up attendance (2003-2009). Flexible parametric survival models were used to estimate age-varying HRs and predicted cumulative probabilities of prostate cancer by androgenetic alopecia categories. Of 9,448 men that attended follow-up and provided data on androgenetic alopecia, we identified 476 prostate cancer cases during a median follow-up of 11 years four months. Cumulative probability of prostate cancer was greater at all ages up to 76 years, for men with vertex versus no androgenetic alopecia at age of 40 years. At age of 76 years, the estimated probabilities converged to 0.15. Vertex androgenetic alopecia at 40 years was also associated with younger age of diagnosis for prostate cancer cases. Vertex androgenetic alopecia at age of 40 years might be a marker of increased risk of early-onset prostate cancer. If confirmed, these results suggest that the apparently conflicting findings of previous studies might be explained by failure to adequately model the age-varying nature of the association between androgenetic alopecia and prostate cancer.

  18. The influence of initial beliefs on judgments of probability.

    Science.gov (United States)

    Yu, Erica C; Lagnado, David A

    2012-01-01

    This study aims to investigate whether experimentally induced prior beliefs affect processing of evidence including the updating of beliefs under uncertainty about the unknown probabilities of outcomes and the structural, outcome-generating nature of the environment. Participants played a gambling task in the form of computer-simulated slot machines and were given information about the slot machines' possible outcomes without their associated probabilities. One group was induced with a prior belief about the outcome space that matched the space of actual outcomes to be sampled; the other group was induced with a skewed prior belief that included the actual outcomes and also fictional higher outcomes. In reality, however, all participants sampled evidence from the same underlying outcome distribution, regardless of priors given. Before and during sampling, participants expressed their beliefs about the outcome distribution (values and probabilities). Evaluation of those subjective probability distributions suggests that all participants' judgments converged toward the observed outcome distribution. However, despite observing no supporting evidence for fictional outcomes, a significant proportion of participants in the skewed priors condition expected them in the future. A probe of the participants' understanding of the underlying outcome-generating processes indicated that participants' judgments were based on the information given in the induced priors and consequently, a significant proportion of participants in the skewed condition believed the slot machines were not games of chance while participants in the control condition believed the machines generated outcomes at random. Beyond Bayesian or heuristic belief updating, priors not only contribute to belief revision but also affect one's deeper understanding of the environment.

  19. Quantum probabilities as Dempster-Shafer probabilities in the lattice of subspaces

    International Nuclear Information System (INIS)

    Vourdas, A.

    2014-01-01

    The orthocomplemented modular lattice of subspaces L[H(d)], of a quantum system with d-dimensional Hilbert space H(d), is considered. A generalized additivity relation which holds for Kolmogorov probabilities is violated by quantum probabilities in the full lattice L[H(d)] (it is only valid within the Boolean subalgebras of L[H(d)]). This suggests the use of more general (than Kolmogorov) probability theories, and here the Dempster-Shafer probability theory is adopted. An operator D(H 1 ,H 2 ), which quantifies deviations from Kolmogorov probability theory is introduced, and it is shown to be intimately related to the commutator of the projectors P(H 1 ),P(H 2 ), to the subspaces H 1 , H 2 . As an application, it is shown that the proof of the inequalities of Clauser, Horne, Shimony, and Holt for a system of two spin 1/2 particles is valid for Kolmogorov probabilities, but it is not valid for Dempster-Shafer probabilities. The violation of these inequalities in experiments supports the interpretation of quantum probabilities as Dempster-Shafer probabilities

  20. Effects of age condition on the distribution and integrity of inorganic fillers in dental resin composites.

    Science.gov (United States)

    D'Alpino, Paulo Henrique Perlatti; Svizero, Nádia da Rocha; Bim Júnior, Odair; Valduga, Claudete Justina; Graeff, Carlos Frederico de Oliveira; Sauro, Salvatore

    2016-06-01

    The aim of this study is to evaluate the distribution of the filler size along with the zeta potential, and the integrity of silane-bonded filler surface in different types of restorative dental composites as a function of the material age condition. Filtek P60 (hybrid composite), Filtek Z250 (small-particle filled composite), Filtek Z350XT (nanofilled composite), and Filtek Silorane (silorane composite) (3M ESPE) were tested at different stage condition (i.e., fresh/new, aged, and expired). Composites were submitted to an accelerated aging protocol (Arrhenius model). Specimens were obtained by first diluting each composite specimen in ethanol and then dispersed in potassium chloride solution (0.001 mol%). Composite fillers were characterized for their zeta potential, mean particle size, size distribution, via poly-dispersion dynamic light scattering. The integrity of the silane-bonded surface of the fillers was characterized by FTIR. The material age influenced significantly the outcomes; Zeta potential, filler characteristics, and silane integrity varied both after aging and expiration. Silorane presented the broadest filler distribution and lowest zeta potential. Nanofilled and silorane composites exhibited decreased peak intensities in the FTIR analysis, indicating a deficiency of the silane integrity after aging or expiry time. Regardless to the material condition, the hybrid and the small-particle-filled composites were more stable overtime as no significant alteration in filler size distribution, diameter, and zeta potential occurred. A deficiency in the silane integrity in the nanofilled and silorane composites seems to be affected by the material stage condition. The materials conditions tested in this study influenced the filler size distribution, the zeta potential, and integrity of the silane adsorbed on fillers in the nanofilled and silorane composites. Thus, this may result in a decrease of the clinical performance of aforementioned composites, in

  1. Modelling detection probabilities to evaluate management and control tools for an invasive species

    Science.gov (United States)

    Christy, M.T.; Yackel Adams, A.A.; Rodda, G.H.; Savidge, J.A.; Tyrrell, C.L.

    2010-01-01

    For most ecologists, detection probability (p) is a nuisance variable that must be modelled to estimate the state variable of interest (i.e. survival, abundance, or occupancy). However, in the realm of invasive species control, the rate of detection and removal is the rate-limiting step for management of this pervasive environmental problem. For strategic planning of an eradication (removal of every individual), one must identify the least likely individual to be removed, and determine the probability of removing it. To evaluate visual searching as a control tool for populations of the invasive brown treesnake Boiga irregularis, we designed a mark-recapture study to evaluate detection probability as a function of time, gender, size, body condition, recent detection history, residency status, searcher team and environmental covariates. We evaluated these factors using 654 captures resulting from visual detections of 117 snakes residing in a 5-ha semi-forested enclosure on Guam, fenced to prevent immigration and emigration of snakes but not their prey. Visual detection probability was low overall (= 0??07 per occasion) but reached 0??18 under optimal circumstances. Our results supported sex-specific differences in detectability that were a quadratic function of size, with both small and large females having lower detection probabilities than males of those sizes. There was strong evidence for individual periodic changes in detectability of a few days duration, roughly doubling detection probability (comparing peak to non-elevated detections). Snakes in poor body condition had estimated mean detection probabilities greater than snakes with high body condition. Search teams with high average detection rates exhibited detection probabilities about twice that of search teams with low average detection rates. Surveys conducted with bright moonlight and strong wind gusts exhibited moderately decreased probabilities of detecting snakes. Synthesis and applications. By

  2. Analytical and numerical studies of creation probabilities of hierarchical trees

    Directory of Open Access Journals (Sweden)

    S.S. Borysov

    2011-03-01

    Full Text Available We consider the creation conditions of diverse hierarchical trees both analytically and numerically. A connection between the probabilities to create hierarchical levels and the probability to associate these levels into a united structure is studied. We argue that a consistent probabilistic picture requires the use of deformed algebra. Our consideration is based on the study of the main types of hierarchical trees, among which both regular and degenerate ones are studied analytically, while the creation probabilities of Fibonacci, scale-free and arbitrary trees are determined numerically.

  3. Oil spill contamination probability in the southeastern Levantine basin.

    Science.gov (United States)

    Goldman, Ron; Biton, Eli; Brokovich, Eran; Kark, Salit; Levin, Noam

    2015-02-15

    Recent gas discoveries in the eastern Mediterranean Sea led to multiple operations with substantial economic interest, and with them there is a risk of oil spills and their potential environmental impacts. To examine the potential spatial distribution of this threat, we created seasonal maps of the probability of oil spill pollution reaching an area in the Israeli coastal and exclusive economic zones, given knowledge of its initial sources. We performed simulations of virtual oil spills using realistic atmospheric and oceanic conditions. The resulting maps show dominance of the alongshore northerly current, which causes the high probability areas to be stretched parallel to the coast, increasing contamination probability downstream of source points. The seasonal westerly wind forcing determines how wide the high probability areas are, and may also restrict these to a small coastal region near source points. Seasonal variability in probability distribution, oil state, and pollution time is also discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. The relationship between maternal education and reported childhood conditions.

    Science.gov (United States)

    Berchick, Edward R

    2016-12-01

    Children of more-educated mothers tend to be healthier than children of less-educated mothers. However, in the United States, evidence for this relationship largely focuses on summary measures of health, such as subjective health status, birth weight, and height. Few studies have examined the relationship between mothers' education and children's reported conditions, the health metric that underlies many policy decisions concerning population health. Contrary to stylized facts about socioeconomic gradients in health, higher detection and reporting rates may lead to higher reporting rates among children of more-educated mothers, despite their better underlying health. This reporting pattern that might not mirror gradients for summary health measures. To examine this possibility, I investigate the association between maternal education and nine health conditions in the 1998-2014 National Health Interview Surveys (n = 176,097). I consider variation in the maternal education gradient across the specific reported conditions that children experience, paying particular attention to how patterns differ across children's ages. Results suggest that, unlike for the income gradient in child health, the relationship between maternal education and reported conditions varies in magnitude and direction across conditions. With some exceptions, the probability of reporting a diagnosed condition increases with maternal schooling. For some diagnoses, like asthma, this relationship is curvilinear, with an inverse gradient for children of the most educated mothers. However, the probability of reporting conditions that require neither diagnosis nor substantial parent-child involvement for detection tends to be flat across maternal education. Contrary to expectations, these relationships tend to be more pronounced for children who are 6 years of age or older than for younger children. These results expand understanding of the production and reporting of early-life health inequalities

  5. Effect of ageing under tropical conditions on the eating qualities of ...

    African Journals Online (AJOL)

    Beef is a major source of animal protein in Ghana but most of it comes from old and poorly conditioned animals, which produce tough meat with poor eating qualities. The eating quality of tough beef can, however, be improved by methods of tenderizing such as ageing, electrical stimulation and application of enzymes.

  6. On a paradox of probability theory

    International Nuclear Information System (INIS)

    Stuart, C.I.J.M.

    1989-01-01

    Costa de Beauregard's proposal concerning physical retrocausality has been shown to fail on two crucial points. However, it is argued that his proposal still merits serious attention. The argument arises from showing that his proposal reveals a paradox involving relations between conditional probabilities, statistical correlations and reciprocal causalities of the type exhibited by cooperative dynamics in physical systems. 4 refs. (Author)

  7. Impact of socioeconomic status and medical conditions on health and healthcare utilization among aging Ghanaians.

    Science.gov (United States)

    Saeed, Bashiru Ii; Xicang, Zhao; Yawson, Alfred Edwin; Nguah, Samuel Blay; Nsowah-Nuamah, Nicholas N N

    2015-03-20

    This study attempts to examine the impact of socioeconomic and medical conditions in health and healthcare utilization among older adults in Ghana. Five separate models with varying input variables were estimated for each response variable. Data (Wave 1 data) were drawn from the World Health Organization Global Ageing and Adult Health (SAGE) conducted during 2007-2008 and included a total of 4770 respondents aged 50+ and 803 aged 18-49 in Ghana. Ordered logits was estimated for self-rated health, and binary logits for functional limitation and healthcare utilization. Our results show that the study provides enough grounds for further research on the interplay between socioeconomic and medical conditions on one hand and the health of the aged on the other. Controlling for socioeconomic status substantially contributes significantly to utilization. Also, aged women experience worse health than men, as shown by functioning assessment, self-rated health, chronic conditions and functional limitations. Women have higher rates of healthcare utilization, as shown by significantly higher rates of hospitalization and outpatient encounters. Expansion of the national health insurance scheme to cover the entire older population--for those in both formal and informal employments--is likely to garner increased access and improved health states for the older population.

  8. On the structural integrity evaluation about aged components

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-08-15

    About one third of the nuclear power plants in Japan have been operated more than 30 years and flaws due to age-related degradation mechanisms have been detected in some components such as piping systems or core shrouds these years. Moreover, several severe earthquakes such as the Tohoku District - off the Pacific Ocean Earthquake or the Niigata-ken Chuetsu-oki Earthquake have struck some nuclear power plants in Japan recent years. Therefore, the structural integrity evaluation about nuclear installations and components considering seismic loads and aging mechanisms has become more and more important. In this study, several evaluation methods were proposed to assess the crack growth rate under the seismic loading conditions, to assess the failure conditions or the realistic failure capacities of the aged piping systems considering seismic or general loading conditions. Furthermore, analysis codes were developed considering aging mechanisms to carry out the integrity evaluation, or the failure probability evaluation which is useful in the seismic PSA evaluation. All of these assessment methods and analysis codes are being used and will be used more and more in the cross-check analyses or the safety reviews about nuclear installations and components. (author)

  9. Resveratrol in prevention and treatment of common clinical conditions of aging

    Directory of Open Access Journals (Sweden)

    M Andrea Markus

    2008-06-01

    Full Text Available M Andrea Markus, Brian J MorrisSchool of Medical Sciences and Bosch Institute, The University of Sydney, Sydney, NSW, AustraliaAbstract: Resveratrol is a potent member of the class of natural, plant-derived chemicals known as polyphenols. These help explain in part why a diet high in fruit and vegetables confers health benefits and are associated with reduced risk of common complex conditions such as cardiovascular disease, cancer, diabetes, and Alzheimer’s disease. We present the latest molecular findings that account for the beneficial actions of resveratrol. The intracellular pathways activated are crucial for anti-oxidant defence, regulation of the cell cycle, mitochondrial energy production, vascular tone, oncogene suppression, and many other phenomena which if unchecked lead to morbidity and mortality from onset and progression of these various diseases. While a healthy diet and lifestyle is strongly recommended in prevention of such conditions, the future bodes well for the use of resveratrol and analogues of higher potency than the natural form for treatment of diseases that afflict humans, particularly as they age.Keywords: resveratrol, longevity, SIRT, wine, aging, cancer

  10. Probability an introduction

    CERN Document Server

    Goldberg, Samuel

    1960-01-01

    Excellent basic text covers set theory, probability theory for finite sample spaces, binomial theorem, probability distributions, means, standard deviations, probability function of binomial distribution, more. Includes 360 problems with answers for half.

  11. The Development of Skin Conductance Fear Conditioning in Children from Ages 3 to 8 Years

    Science.gov (United States)

    Gao, Yu; Raine, Adrian; Venables, Peter H.; Dawson, Michael E.; Mednick, Sarnoff A.

    2010-01-01

    Although fear conditioning is an important psychological construct implicated in behavioral and emotional problems, little is known about how it develops in early childhood. Using a differential, partial reinforcement conditioning paradigm, this longitudinal study assessed skin conductance conditioned responses in 200 children at ages 3, 4, 5, 6,…

  12. Models for probability and statistical inference theory and applications

    CERN Document Server

    Stapleton, James H

    2007-01-01

    This concise, yet thorough, book is enhanced with simulations and graphs to build the intuition of readersModels for Probability and Statistical Inference was written over a five-year period and serves as a comprehensive treatment of the fundamentals of probability and statistical inference. With detailed theoretical coverage found throughout the book, readers acquire the fundamentals needed to advance to more specialized topics, such as sampling, linear models, design of experiments, statistical computing, survival analysis, and bootstrapping.Ideal as a textbook for a two-semester sequence on probability and statistical inference, early chapters provide coverage on probability and include discussions of: discrete models and random variables; discrete distributions including binomial, hypergeometric, geometric, and Poisson; continuous, normal, gamma, and conditional distributions; and limit theory. Since limit theory is usually the most difficult topic for readers to master, the author thoroughly discusses mo...

  13. Probability 1/e

    Science.gov (United States)

    Koo, Reginald; Jones, Martin L.

    2011-01-01

    Quite a number of interesting problems in probability feature an event with probability equal to 1/e. This article discusses three such problems and attempts to explain why this probability occurs with such frequency.

  14. Conditional Melanoma Cancer Survival in the United States

    Directory of Open Access Journals (Sweden)

    Ray M. Merrill

    2016-02-01

    Full Text Available Beyond relative survival, which indicates the likelihood that patients will not die from causes associated with their cancer, conditional relative survival probabilities provide further useful prognostic information to cancer patients, tailored to the time already survived from diagnosis. This study presents conditional relative survival for melanoma patients in the United States, diagnosed during 2000–2008 and followed through 2012. Analyses are based on 62,803 male and 50,261 female cases in population-based cancer registries in the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. Five-year relative survival estimates are presented for melanoma patients who have already survived one, two, three, four, or five years after the initial diagnosis. Five- and ten-year relative survival decreases with age, stage at diagnosis, and is lower among males, Blacks, and Hispanics. Five-year conditional relative survival improves with each year already survived. The potential for improvement in five-year conditional relative survival is greatest for older age, males, Blacks, Hispanics, and in later staged cases. For local disease, five-year conditional relative survival was significantly lower in ages greater than 65 years and in Blacks. It was significantly higher in females, non-Hispanics, and married individuals. Age had a greater inverse relationship with five-year survival in later staged disease. A similar result occurred for females and married individuals. In contrast, non-Hispanics had better five-year survival if diagnosed with local or regional disease, but not distant disease.

  15. Effect of bite-raised condition on the hippocampal cholinergic system of aged SAMP8 mice.

    Science.gov (United States)

    Katayama, Tasuku; Mori, Daisuke; Miyake, Hidekazu; Fujiwara, Shuu; Ono, Yumie; Takahashi, Toru; Onozuka, Minoru; Kubo, Kin-Ya

    2012-06-27

    Occlusal disharmony induces chronic stress, which results in learning deficits in association with the morphologic changes in the hippocampus, e.g., neuronal degeneration and increased hypertrophied glial fibrillary acidic protein-positive cells. To investigate the mechanisms underlying impaired hippocampal function resulting from occlusal disharmony, we examined the effects of the bite-raised condition on the septohippocampal cholinergic system by assessing acetylcholine release in the hippocampus and choline acetyltransferase immunoreactivity in the medial septal nucleus in aged SAMP8 mice that underwent the bite raising procedure. Aged bite-raised mice showed decreased acetylcholine release in the hippocampus and a reduced number of choline acetyltransferase-immunopositive neurons in the medial septal nucleus compared to age-matched control mice. These findings suggest that the bite-raised condition in aged SAMP8 mice enhances the age-related decline in the septohippocampal cholinergic system, leading to impaired learning. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  16. A generalized electron energy probability function for inductively coupled plasmas under conditions of nonlocal electron kinetics

    Science.gov (United States)

    Mouchtouris, S.; Kokkoris, G.

    2018-01-01

    A generalized equation for the electron energy probability function (EEPF) of inductively coupled Ar plasmas is proposed under conditions of nonlocal electron kinetics and diffusive cooling. The proposed equation describes the local EEPF in a discharge and the independent variable is the kinetic energy of electrons. The EEPF consists of a bulk and a depleted tail part and incorporates the effect of the plasma potential, Vp, and pressure. Due to diffusive cooling, the break point of the EEPF is eVp. The pressure alters the shape of the bulk and the slope of the tail part. The parameters of the proposed EEPF are extracted by fitting to measure EEPFs (at one point in the reactor) at different pressures. By coupling the proposed EEPF with a hybrid plasma model, measurements in the gaseous electronics conference reference reactor concerning (a) the electron density and temperature and the plasma potential, either spatially resolved or at different pressure (10-50 mTorr) and power, and (b) the ion current density of the electrode, are well reproduced. The effect of the choice of the EEPF on the results is investigated by a comparison to an EEPF coming from the Boltzmann equation (local electron kinetics approach) and to a Maxwellian EEPF. The accuracy of the results and the fact that the proposed EEPF is predefined renders its use a reliable alternative with a low computational cost compared to stochastic electron kinetic models at low pressure conditions, which can be extended to other gases and/or different electron heating mechanisms.

  17. Measurement of Survival Time in Brachionus Rotifers: Synchronization of Maternal Conditions.

    Science.gov (United States)

    Kaneko, Gen; Yoshinaga, Tatsuki; Gribble, Kristin E; Welch, David M; Ushio, Hideki

    2016-07-22

    Rotifers are microscopic cosmopolitan zooplankton used as models in ecotoxicological and aging studies due to their several advantages such as short lifespan, ease of culture, and parthenogenesis that enables clonal culture. However, caution is required when measuring their survival time as it is affected by maternal age and maternal feeding conditions. Here we provide a protocol for powerful and reproducible measurement of the survival time in Brachionus rotifers following a careful synchronization of culture conditions over several generations. Empirically, poor synchronization results in early mortality and a gradual decrease in survival rate, thus resulting in weak statistical power. Indeed, under such conditions, calorie restriction (CR) failed to significantly extend the lifespan of B. plicatilis although CR-induced longevity has been demonstrated with well-synchronized rotifer samples in past and present studies. This protocol is probably useful for other invertebrate models, including the fruitfly Drosophila melanogaster and the nematode Caenorhabditis elegans, because maternal age effects have also been reported in these species.

  18. Pemodelan Markov Switching Dengan Time-varying Transition Probability

    OpenAIRE

    Savitri, Anggita Puri; Warsito, Budi; Rahmawati, Rita

    2016-01-01

    Exchange rate or currency is an economic variable which reflects country's state of economy. It fluctuates over time because of its ability to switch the condition or regime caused by economic and political factors. The changes in the exchange rate are depreciation and appreciation. Therefore, it could be modeled using Markov Switching with Time-Varying Transition Probability which observe the conditional changes and use information variable. From this model, time-varying transition probabili...

  19. Changes in bone tissue under conditions of hypokinesia and in connection with age

    Science.gov (United States)

    Podrushnyak, E. P.; Suslov, E. I.

    1980-01-01

    X-ray micrography was used to study the optical density of the blackening of X-ray photographs made of five bones in 9 young people (ages 24 to 29) before and after strict bed rest for 16 to 37 days. Photometric studies of the X-ray film determined the relative concentration of bone structure before and after hypokinesia. In addition, the bone tissues of 25 cadavers of practically healthy individuals (aged 18 to 70) who died from injuries were investigated using X-ray structural analysis. Results show that the reaction to the state of hypokinesia is not uniform in different individuals and is quite often directly reversed. It was established that pronounced osteoporosis can be found in a relatively short time after conditions of hypokinesia in healthy young individuals. Results show that the stabilization of the crystalline structure of hydroxyapatite, especially its crystal formation, is finished by the age of 20 to 25. From 25 to 60, the crystal lattice remains in stable condition but X-ray analysis shows a reduction in the hydroxyapatite density.

  20. Non-Archimedean Probability

    NARCIS (Netherlands)

    Benci, Vieri; Horsten, Leon; Wenmackers, Sylvia

    We propose an alternative approach to probability theory closely related to the framework of numerosity theory: non-Archimedean probability (NAP). In our approach, unlike in classical probability theory, all subsets of an infinite sample space are measurable and only the empty set gets assigned

  1. Allelic drop-out probabilities estimated by logistic regression

    DEFF Research Database (Denmark)

    Tvedebrink, Torben; Eriksen, Poul Svante; Asplund, Maria

    2012-01-01

    We discuss the model for estimating drop-out probabilities presented by Tvedebrink et al. [7] and the concerns, that have been raised. The criticism of the model has demonstrated that the model is not perfect. However, the model is very useful for advanced forensic genetic work, where allelic drop-out...... is occurring. With this discussion, we hope to improve the drop-out model, so that it can be used for practical forensic genetics and stimulate further discussions. We discuss how to estimate drop-out probabilities when using a varying number of PCR cycles and other experimental conditions....

  2. Handbook of probability

    CERN Document Server

    Florescu, Ionut

    2013-01-01

    THE COMPLETE COLLECTION NECESSARY FOR A CONCRETE UNDERSTANDING OF PROBABILITY Written in a clear, accessible, and comprehensive manner, the Handbook of Probability presents the fundamentals of probability with an emphasis on the balance of theory, application, and methodology. Utilizing basic examples throughout, the handbook expertly transitions between concepts and practice to allow readers an inclusive introduction to the field of probability. The book provides a useful format with self-contained chapters, allowing the reader easy and quick reference. Each chapter includes an introductio

  3. Probability-1

    CERN Document Server

    Shiryaev, Albert N

    2016-01-01

    This book contains a systematic treatment of probability from the ground up, starting with intuitive ideas and gradually developing more sophisticated subjects, such as random walks, martingales, Markov chains, the measure-theoretic foundations of probability theory, weak convergence of probability measures, and the central limit theorem. Many examples are discussed in detail, and there are a large number of exercises. The book is accessible to advanced undergraduates and can be used as a text for independent study. To accommodate the greatly expanded material in the third edition of Probability, the book is now divided into two volumes. This first volume contains updated references and substantial revisions of the first three chapters of the second edition. In particular, new material has been added on generating functions, the inclusion-exclusion principle, theorems on monotonic classes (relying on a detailed treatment of “π-λ” systems), and the fundamental theorems of mathematical statistics.

  4. Probability Machines: Consistent Probability Estimation Using Nonparametric Learning Machines

    Science.gov (United States)

    Malley, J. D.; Kruppa, J.; Dasgupta, A.; Malley, K. G.; Ziegler, A.

    2011-01-01

    Summary Background Most machine learning approaches only provide a classification for binary responses. However, probabilities are required for risk estimation using individual patient characteristics. It has been shown recently that every statistical learning machine known to be consistent for a nonparametric regression problem is a probability machine that is provably consistent for this estimation problem. Objectives The aim of this paper is to show how random forests and nearest neighbors can be used for consistent estimation of individual probabilities. Methods Two random forest algorithms and two nearest neighbor algorithms are described in detail for estimation of individual probabilities. We discuss the consistency of random forests, nearest neighbors and other learning machines in detail. We conduct a simulation study to illustrate the validity of the methods. We exemplify the algorithms by analyzing two well-known data sets on the diagnosis of appendicitis and the diagnosis of diabetes in Pima Indians. Results Simulations demonstrate the validity of the method. With the real data application, we show the accuracy and practicality of this approach. We provide sample code from R packages in which the probability estimation is already available. This means that all calculations can be performed using existing software. Conclusions Random forest algorithms as well as nearest neighbor approaches are valid machine learning methods for estimating individual probabilities for binary responses. Freely available implementations are available in R and may be used for applications. PMID:21915433

  5. Gravity and count probabilities in an expanding universe

    Science.gov (United States)

    Bouchet, Francois R.; Hernquist, Lars

    1992-01-01

    The time evolution of nonlinear clustering on large scales in cold dark matter, hot dark matter, and white noise models of the universe is investigated using N-body simulations performed with a tree code. Count probabilities in cubic cells are determined as functions of the cell size and the clustering state (redshift), and comparisons are made with various theoretical models. We isolate the features that appear to be the result of gravitational instability, those that depend on the initial conditions, and those that are likely a consequence of numerical limitations. More specifically, we study the development of skewness, kurtosis, and the fifth moment in relation to variance, the dependence of the void probability on time as well as on sparseness of sampling, and the overall shape of the count probability distribution. Implications of our results for theoretical and observational studies are discussed.

  6. Prevalence and potential factors associated with probable sleep or awake bruxism and dentin hypersensitivity in undergraduate students

    Directory of Open Access Journals (Sweden)

    Neusa Barros DANTAS-NETA

    Full Text Available OBJECTIVE: To measure the prevalence of probable sleep or awake bruxism and cervical dentin hypersensitivity of undergraduate students and to determine the symptoms associated with these conditions.METHODOLOGY: This was a cross-sectional study. A diagnosis of probable bruxism was reached when students reported clenching or grinding of the teeth during sleep and/or wakefulness, and when they also presented some of the signs and symptoms of bruxism and masseter muscle pain on palpation. Cervical dentinal hypersensitivity was diagnosed by testing for sensitivity to pain in the cervical region of the teeth. Pain was triggered either by touch (using a #5 probe or by an air jet spray. The sample consisted of 306 university students aged between 19 and 35 years old. The data were stored and analysed using SPSS software, version 15.0 for Windows.RESULT: The prevalence of probable bruxism was 34.3%, with no predominance regarding sex. Probable awake bruxism was more prevalent (61.9%, mostly occurring when the individual reported being in a state of mental concentration (63.1%. There was no association between probable sleep or awake bruxism and dentin hypersensitivity (p = 0.195. Individuals with probable sleep bruxism had increased odds of having muscular pain in the face upon waking (OR = 14.14, 95% CI 5.06-39.55, and those with probable awake bruxism had a increased odds of having facial muscle fatigue when chewing or talking for a long time (OR = 2.88, 95% CI 1.53-5.43 and muscular pain in the face upon waking (OR = 5.31, 95% CI 1.93-14.62.CONCLUSION: The prevalence of probable bruxism was 34.3% and that of HDC was 57.8%, with 22.2% of these subjects also showing probable bruxism. Individuals with probable bruxism tended to have a higher odds of facial pain when they awakened and when chewing or talking for long periods. There were no associations between probable sleep and awake bruxism and cervical dentin hypersensitivity.

  7. Impact probabilities of meteoroid streams with artificial satellites: An assessment

    International Nuclear Information System (INIS)

    Foschini, L.; Cevolani, G.

    1997-01-01

    Impact probabilities of artificial satellites with meteoroid streams were calculated using data collected with the CNR forward scatter (FS) bistatic radar over the Bologna-Lecce baseline (about 700 km). Results show that impact probabilities are 2 times higher than other previously calculated values. Nevertheless, although catastrophic impacts are still rare even in the case of meteor storm conditions, it is expected that high meteoroid fluxes can erode satellites surfaces and weaken their external structures

  8. Probability analysis of WWER-1000 fuel elements behavior under steady-state, transient and accident conditions of reactor operation

    International Nuclear Information System (INIS)

    Tutnov, A.; Alexeev, E.

    2001-01-01

    'PULSAR-2' and 'PULSAR+' codes make it possible to simulate thermo-mechanical and thermo-physical parameters of WWER fuel elements. The probabilistic approach is used instead of traditional deterministic one to carry out a sensitive study of fuel element behavior under steady-state operation mode. Fuel elements initial parameters are given as a density of the probability distributions. Calculations are provided for all possible combinations of initial data as fuel-cladding gap, fuel density and gas pressure. Dividing values of these parameters to intervals final variants for calculations are obtained . Intervals of permissible fuel-cladding gap size have been divided to 10 equal parts, fuel density and gas pressure - to 5 parts. Probability of each variant realization is determined by multiplying the probabilities of separate parameters, because the tolerances of these parameters are distributed independently. Simulation results are turn out in the probabilistic bar charts. The charts present probability distribution of the changes in fuel outer diameter, hoop stress kinetics and fuel temperature versus irradiation time. A normative safety factor is introduced for control of any criterion realization and for determination of a reserve to the criteria failure. A probabilistic analysis of fuel element behavior under Reactivity Initiating Accident (RIA) is also performed and probability fuel element depressurization under hypothetical RIA is presented

  9. Janus-faced probability

    CERN Document Server

    Rocchi, Paolo

    2014-01-01

    The problem of probability interpretation was long overlooked before exploding in the 20th century, when the frequentist and subjectivist schools formalized two conflicting conceptions of probability. Beyond the radical followers of the two schools, a circle of pluralist thinkers tends to reconcile the opposing concepts. The author uses two theorems in order to prove that the various interpretations of probability do not come into opposition and can be used in different contexts. The goal here is to clarify the multifold nature of probability by means of a purely mathematical approach and to show how philosophical arguments can only serve to deepen actual intellectual contrasts. The book can be considered as one of the most important contributions in the analysis of probability interpretation in the last 10-15 years.

  10. Ruin probabilities

    DEFF Research Database (Denmark)

    Asmussen, Søren; Albrecher, Hansjörg

    The book gives a comprehensive treatment of the classical and modern ruin probability theory. Some of the topics are Lundberg's inequality, the Cramér-Lundberg approximation, exact solutions, other approximations (e.g., for heavy-tailed claim size distributions), finite horizon ruin probabilities......, extensions of the classical compound Poisson model to allow for reserve-dependent premiums, Markov-modulation, periodicity, change of measure techniques, phase-type distributions as a computational vehicle and the connection to other applied probability areas, like queueing theory. In this substantially...... updated and extended second version, new topics include stochastic control, fluctuation theory for Levy processes, Gerber–Shiu functions and dependence....

  11. Interpretations of probability

    CERN Document Server

    Khrennikov, Andrei

    2009-01-01

    This is the first fundamental book devoted to non-Kolmogorov probability models. It provides a mathematical theory of negative probabilities, with numerous applications to quantum physics, information theory, complexity, biology and psychology. The book also presents an interesting model of cognitive information reality with flows of information probabilities, describing the process of thinking, social, and psychological phenomena.

  12. The prevalence of probable neuropathic pain in the US: results from a multimodal general-population health survey

    Directory of Open Access Journals (Sweden)

    DiBonaventura MD

    2017-11-01

    Full Text Available Marco D DiBonaventura,1 Alesia Sadosky,2 Kristen Concialdi,1 Markay Hopps,2 Ian Kudel,1 Bruce Parsons,2 Joseph C Cappelleri,3 Patrick Hlavacek,2 Andrea H Alexander,2 Brett R Stacey,4 John D Markman,5 John T Farrar6 1Health Outcomes Practice, Kantar Health, 2Pfizer Inc, New York, NY, 3Pfizer Inc, Groton, CT, 4University of Washington, Seattle, WA, 5University of Rochester School of Medicine and Dentistry, Rochester, NY, 6University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, US Background: The prevalence of neuropathic pain (NeP has been estimated within specific health conditions; however, there are no published data on its broad prevalence in the US. The current exploratory study addresses this gap using the validated PainDetect questionnaire as a screener for probable NeP in a general-population health survey conducted with a multimodal recruitment strategy to maximize demographic representativeness. Materials and methods: Adult respondents were recruited from a combination of Internet panels, telephone lists, address lists, mall-based interviews, and store-receipt invitations using a random stratified-sampling framework, with strata defined by age, sex, and race/ethnicity. Older persons and minorities were oversampled to improve prevalence estimates. Results were weighted to match the total adult US population using US Census data. Demographic information was collected, and respondents who experienced physical pain in the past 12 months completed the PainDetect and provided additional pain history. A cutoff score of 19 or greater on the PainDetect was used to define probable NeP. Results: A total of 24,925 respondents (average response rate 2.5% provided demographic data (52.2% female, mean age 51.5 years; 15,751 respondents reported pain (63.7%, of which 2,548 (15.7%, 95% confidence interval 14.9%–16.5% had probable NeP based on the PainDetect, which was 10% (95% confidence interval 9.5%–10.5% of all respondents. Among

  13. Socio-demographics characteristics and health conditions of older homeless persons of Lima, Peru

    OpenAIRE

    Moquillaza-Risco, Marlene; Programa Nacional Vida Digna (PNVD), Ministerio de la Mujer y Poblaciones Vulnerables. Lima, Perú.; León, Elsa; Programa Nacional Vida Digna (PNVD), Ministerio de la Mujer y Poblaciones Vulnerables. Lima, Perú.; Dongo, Mario; Programa Nacional Vida Digna (PNVD), Ministerio de la Mujer y Poblaciones Vulnerables. Lima, Perú.; Munayco, César V.; Programa Nacional Vida Digna (PNVD), Ministerio de la Mujer y Poblaciones Vulnerables. Lima, Perú.

    2015-01-01

    Objectives. Determine the socio-demographics characteristics and health conditions of older homeless persons at the time of enrollment into the National Program “Vida Digna” and the probability of functional dependency by age, and stratified by gender and cognitive impairment. Materials ande methods. We performed a cross sectional study, reviewing all registration forms of the program in order to identify socio-demographic variables and health conditions of older homeless persons at the time ...

  14. Age of Parental Concern, Diagnosis, and Service Initiation among Children with Autism Spectrum Disorder

    Science.gov (United States)

    Zablotsky, Benjamin; Colpe, Lisa J.; Pringle, Beverly A.; Kogan, Michael D.; Rice, Catherine; Blumberg, Stephen J.

    2017-01-01

    Children with autism spectrum disorder (ASD) require substantial support to address the core symptoms of ASD and co-occurring behavioral/developmental conditions. This study explores the early diagnostic experiences of school-aged children with ASD using survey data from a large probability-based national sample. Multivariate linear regressions…

  15. Review of Physicochemical-Based Diagnostic Techniques for Assessing Insulation Condition in Aged Transformers

    Directory of Open Access Journals (Sweden)

    Janvier Sylvestre N’cho

    2016-05-01

    Full Text Available A power transformer outage has a dramatic financial consequence not only for electric power systems utilities but also for interconnected customers. The service reliability of this important asset largely depends upon the condition of the oil-paper insulation. Therefore, by keeping the qualities of oil-paper insulation system in pristine condition, the maintenance planners can reduce the decline rate of internal faults. Accurate diagnostic methods for analyzing the condition of transformers are therefore essential. Currently, there are various electrical and physicochemical diagnostic techniques available for insulation condition monitoring of power transformers. This paper is aimed at the description, analysis and interpretation of modern physicochemical diagnostics techniques for assessing insulation condition in aged transformers. Since fields and laboratory experiences have shown that transformer oil contains about 70% of diagnostic information, the physicochemical analyses of oil samples can therefore be extremely useful in monitoring the condition of power transformers.

  16. [Age-related features of neuromuscular function in rats with hyperthyroidism].

    Science.gov (United States)

    Nerush, P O; Makiĭ, Ie A; Rodyns'kyĭ, O H

    2001-01-01

    Studied features of functioning of nervous-muscular system at white rats of two age groups: preadolescent (5 weeks) and puberal (24 weeks), in conditions experimental hyperthyroidism (HT). It is established, that in conditions HT at action of the raised concentration thyroxine characteristics of excitation gastrocnemius muscles essentially changed at irritation of a sciatic nerve in groups preadolescent and puberal animals. In all age groups in conditions HT increase of a threshold of excitation gastrocnemius muscles is marked at indirect stimulation and decrease at direct stimulation; also in all age groups in conditions HT reduction of time chronaxy muscles is fixed, both at direct, and at indirect irritation. At preadolescent animals, as against puberal in conditions HT at action of the raised concentration thyroxine on nervous-muscular system it is not revealed authentic change of the latent period and amplitude of potential of action (PA). The conclusion is made, that in conditions HT change of a threshold of excitation and chronaxy gastrocnemius muscles both at direct, and at indirect irritation do not carry age specificity and have an identical orientation, both at preadolescent, and at puberal rats. At preadolescent animals in conditions HT, as against puberal the parameter of amplitude and latent period PA authentically did not change, that can testify to smaller sensitivity of the caused answers gastrocnemius muscles to the raised concentration thyroxine, probably, by virtue of immaturity peripheral neuromotor the device.

  17. Gates to retirement and gender differences: Macroeconomic conditions, job satisfaction, and age.

    Science.gov (United States)

    Axelrad, Hila; Mcnamara, Tay K

    2017-08-04

    The different pathways out of the labor force have been the focus of many recent studies, yet not enough scholarly attention has been paid to the effect of country-level, individual, and job characteristics and their potentially different influence across genders. The current article examines the relationships between retirement decisions and macroeconomic conditions, personal characteristics, and job satisfaction, while focusing on gender differences. Data came from 16,337 respondents in 13 European countries that participated in the Survey of Health, Ageing and Retirement in Europe (SHARE). We find that the relative importance of macroeconomic conditions and job satisfaction differs by gender.

  18. Probability and logical structure of statistical theories

    International Nuclear Information System (INIS)

    Hall, M.J.W.

    1988-01-01

    A characterization of statistical theories is given which incorporates both classical and quantum mechanics. It is shown that each statistical theory induces an associated logic and joint probability structure, and simple conditions are given for the structure to be of a classical or quantum type. This provides an alternative for the quantum logic approach to axiomatic quantum mechanics. The Bell inequalities may be derived for those statistical theories that have a classical structure and satisfy a locality condition weaker than factorizability. The relation of these inequalities to the issue of hidden variable theories for quantum mechanics is discussed and clarified

  19. When does inferring reputation probability countervail temptation in cooperative behaviors for the prisoners’ dilemma game?

    International Nuclear Information System (INIS)

    Dai, Yu; Lu, Peng

    2015-01-01

    In evolutionary games, the temptation mechanism reduces cooperation percentage while the reputation mechanism promotes it. Inferring reputation theory proposes that agent's imitating neighbors with the highest reputation takes place with a probability. Although reputation promotes cooperation, when and how it enhances cooperation is still a question. This paper investigates the condition where the inferring reputation probability promotes cooperation. Hence, the effects of reputation and temptation on cooperation are explored under the spatial prisoners’ dilemma game, utilizing the methods of simulation and statistical analysis. Results show that temptation reduces cooperation unconditionally while reputation promotes it conditionally, i.e. reputation countervails temptation conditionally. When the inferring reputation probability is less than 0.5, reputation promotes cooperation substantially and thus countervails temptation. However, when the inferring reputation probability is larger than 0.5, its contribution to cooperation is relatively weak and cannot prevent temptation from undermining cooperation. Reputation even decreases cooperation together with temptation when the probability is higher than 0.8. It should be noticed that inferring reputation does not always succeed to countervail temptation and there is a specific interval for it to promote cooperation

  20. The Negated Conditional: A Litmus Test for the Suppositional Conditional?

    Science.gov (United States)

    Handley, Simon J.; Evans, Jonathan St. B. T.; Thompson, Valerie A.

    2006-01-01

    Under the suppositional account of conditionals, when people think about a conditional assertion, "if p then q," they engage in a mental simulation in which they imagine p holds and evaluate the probability that q holds under this supposition. One implication of this account is that belief in a conditional equates to conditional probability…

  1. Knock probability estimation through an in-cylinder temperature model with exogenous noise

    Science.gov (United States)

    Bares, P.; Selmanaj, D.; Guardiola, C.; Onder, C.

    2018-01-01

    This paper presents a new knock model which combines a deterministic knock model based on the in-cylinder temperature and an exogenous noise disturbing this temperature. The autoignition of the end-gas is modelled by an Arrhenius-like function and the knock probability is estimated by propagating a virtual error probability distribution. Results show that the random nature of knock can be explained by uncertainties at the in-cylinder temperature estimation. The model only has one parameter for calibration and thus can be easily adapted online. In order to reduce the measurement uncertainties associated with the air mass flow sensor, the trapped mass is derived from the in-cylinder pressure resonance, which improves the knock probability estimation and reduces the number of sensors needed for the model. A four stroke SI engine was used for model validation. By varying the intake temperature, the engine speed, the injected fuel mass, and the spark advance, specific tests were conducted, which furnished data with various knock intensities and probabilities. The new model is able to predict the knock probability within a sufficient range at various operating conditions. The trapped mass obtained by the acoustical model was compared in steady conditions by using a fuel balance and a lambda sensor and differences below 1 % were found.

  2. Quality of life and probable psychological distress among male workers at a construction site, Kolar district, Karnataka, India.

    Science.gov (United States)

    Mathew, Geethu; Ramesh, Naveen; Shanbhag, Deepthi; Goud, Ramakrishna; Subramanian, Sharan; Lobo, Carol; Xavier, Alex; Dasari, Prudhvi

    2016-01-01

    The construction industry, which mainly consists of migrant labouers is one of the largest employers in the unorganized sector in India. These workers work in poor conditions and are often vulnerable to exploitation. These workers also do not have health care benefits and often these factors lead to poor quality of life (QOL) and psychological distress. To assess the QOL, probable psychological distress and associated factors among male construction workers. A cross-sectional study was conducted between September 2013 and November 2013 among 404 male workers. These construction workers were enrolled by consecutive sampling at a construction area in Kolar district, Kaarnataka, India. The study tools used were World Health Organization (WHO) QOL-BREF and 12-Item General Health Questionnaire (GHQ-12) to assess QOL and probable psychological distress, respectively. The transformed scores in WHO QOL-BREF in all four domains ranged 0-100. The four domain scores are scaled in a positive direction with higher scores indicating a higher QOL. Associations were done using statistical tests such as Chi-square, correlation, regression, independent samples t-test, and analysis of variance (ANOVA). A total of 404 male workers with a mean age of 25.6 ± 7.3 years were studied. Mean scores of various domains of QOL were 68.5 ± 13.7 (physical), 59.9 ± 13.5 (psychological), 64.3 ± 16.4 (social), and 44.1 ± 12.8 (environmental). On the self- rating scale, 59 (14.6%) workers were rated as having poor QOL. The prevalence of probable psychological distress was 27.5%. Factors such as increasing age, being currently married, and low educational status were found to be significantly associated (P psychological distress. There was a significant negative correlation (P psychological distress and a positive correlation between income and QOL. The QOL in the environmental domain, which mainly deals with living conditions, health, and recreational facilities was found to be poor and there

  3. SureTrak Probability of Impact Display

    Science.gov (United States)

    Elliott, John

    2012-01-01

    The SureTrak Probability of Impact Display software was developed for use during rocket launch operations. The software displays probability of impact information for each ship near the hazardous area during the time immediately preceding the launch of an unguided vehicle. Wallops range safety officers need to be sure that the risk to humans is below a certain threshold during each use of the Wallops Flight Facility Launch Range. Under the variable conditions that can exist at launch time, the decision to launch must be made in a timely manner to ensure a successful mission while not exceeding those risk criteria. Range safety officers need a tool that can give them the needed probability of impact information quickly, and in a format that is clearly understandable. This application is meant to fill that need. The software is a reuse of part of software developed for an earlier project: Ship Surveillance Software System (S4). The S4 project was written in C++ using Microsoft Visual Studio 6. The data structures and dialog templates from it were copied into a new application that calls the implementation of the algorithms from S4 and displays the results as needed. In the S4 software, the list of ships in the area was received from one local radar interface and from operators who entered the ship information manually. The SureTrak Probability of Impact Display application receives ship data from two local radars as well as the SureTrak system, eliminating the need for manual data entry.

  4. Improving Ranking Using Quantum Probability

    OpenAIRE

    Melucci, Massimo

    2011-01-01

    The paper shows that ranking information units by quantum probability differs from ranking them by classical probability provided the same data used for parameter estimation. As probability of detection (also known as recall or power) and probability of false alarm (also known as fallout or size) measure the quality of ranking, we point out and show that ranking by quantum probability yields higher probability of detection than ranking by classical probability provided a given probability of ...

  5. Setting the light conditions for measuring root transparency for age-at-death estimation methods.

    Science.gov (United States)

    Adserias-Garriga, Joe; Nogué-Navarro, Laia; Zapico, Sara C; Ubelaker, Douglas H

    2018-03-01

    Age-at-death estimation is one of the main goals in forensic identification, being an essential parameter to determine the biological profile, narrowing the possibility of identification in cases involving missing persons and unidentified bodies. The study of dental tissues has been long considered as a proper tool for age estimation with several age estimation methods based on them. Dental age estimation methods can be divided into three categories: tooth formation and development, post-formation changes, and histological changes. While tooth formation and growth changes are important for fetal and infant consideration, when the end of dental and skeletal growth is achieved, post-formation or biochemical changes can be applied. Lamendin et al. in J Forensic Sci 37:1373-1379, (1992) developed an adult age estimation method based on root transparency and periodontal recession. The regression formula demonstrated its accuracy of use for 40 to 70-year-old individuals. Later on, Prince and Ubelaker in J Forensic Sci 47(1):107-116, (2002) evaluated the effects of ancestry and sex and incorporated root height into the equation, developing four new regression formulas for males and females of African and European ancestry. Even though root transparency is a key element in the method, the conditions for measuring this element have not been established. The aim of the present study is to set the light conditions measured in lumens that offer greater accuracy when applying the Lamendin et al. method modified by Prince and Ubelaker. The results must be also taken into account in the application of other age estimation methodologies using root transparency to estimate age-at-death.

  6. Social Support and Coping Styles in Predicting Suicide Probability among Turkish Adolescents

    Science.gov (United States)

    Cenkseven-Önder, Fulya

    2018-01-01

    This study aims to investigate whether the perceived social support and coping styles are predictors of suicide probability by gender. The study was conducted with 445 high schools students, 227 girls, and 218 boys. The participants were aged between 14 and 18, and their average age was 15.90. Data were collected through the "Multidimensional…

  7. Assessment of students’ health condition by indicators of adaptation potential, biological age and bio-energetic reserves of organism

    Directory of Open Access Journals (Sweden)

    O.V. Martyniuk

    2015-06-01

    Full Text Available Purpose: to assess students’ health condition by indicators of adaptation potential, biological age and express-assessment. Material: in the research 47 first and second year girl students participated, who belonged to main health group. Results: we distributed the girl students into three groups: 14.89% of them were included in group with “safe” health condition; 34.04% - in group of “third state”; 51.06% were related to group with “ dangerous” health condition. We established that dangerous level was characterized by energy potential of below middle and low level. It is accompanied by accelerated processes of organism’s age destructions and tension of regulation mechanisms. Conclusions: the received results permit to further develop and generalize the data of students’ health’s assessment by indicators of adaptation potentials, biological age and physical health’s condition.

  8. The Probability of Uranium Deposit Occurrences at Hatapang and Its Surrounding

    International Nuclear Information System (INIS)

    Soepradto-Tjokrokardono; Ngadenin

    2004-01-01

    This study was carried out based on a geological condition of Hatapang and is surroundings areas that are favourable for uranium accumulation, which are indicated by the existence of granite high uranium content, having mobilizations process and uranium trapping rocks. Referring to the plate tectonic and geochemical situation of Hatapang, those condition will give a significant indications for the possible occurrence of deposit of uranium in the area. The goal of this study is to know the probability occurrences of uranium deposit based on the regional tectonic, geology, mineralogy, geochemical, and radioactivity characters. It is concluded that Hatapang granite is potential for U source granite, and U deposit of black shale type is probably accurate in this area. (author)

  9. On the Possibility of Assigning Probabilities to Singular Cases, or: Probability Is Subjective Too!

    Directory of Open Access Journals (Sweden)

    Mark R. Crovelli

    2009-06-01

    Full Text Available Both Ludwig von Mises and Richard von Mises claimed that numerical probability could not be legitimately applied to singular cases. This paper challenges this aspect of the von Mises brothers’ theory of probability. It is argued that their denial that numerical probability could be applied to singular cases was based solely upon Richard von Mises’ exceptionally restrictive definition of probability. This paper challenges Richard von Mises’ definition of probability by arguing that the definition of probability necessarily depends upon whether the world is governed by time-invariant causal laws. It is argued that if the world is governed by time-invariant causal laws, a subjective definition of probability must be adopted. It is further argued that both the nature of human action and the relative frequency method for calculating numerical probabilities both presuppose that the world is indeed governed by time-invariant causal laws. It is finally argued that the subjective definition of probability undercuts the von Mises claim that numerical probability cannot legitimately be applied to singular, non-replicable cases.

  10. Dopaminergic Drug Effects on Probability Weighting during Risky Decision Making.

    Science.gov (United States)

    Ojala, Karita E; Janssen, Lieneke K; Hashemi, Mahur M; Timmer, Monique H M; Geurts, Dirk E M; Ter Huurne, Niels P; Cools, Roshan; Sescousse, Guillaume

    2018-01-01

    Dopamine has been associated with risky decision-making, as well as with pathological gambling, a behavioral addiction characterized by excessive risk-taking behavior. However, the specific mechanisms through which dopamine might act to foster risk-taking and pathological gambling remain elusive. Here we test the hypothesis that this might be achieved, in part, via modulation of subjective probability weighting during decision making. Human healthy controls ( n = 21) and pathological gamblers ( n = 16) played a decision-making task involving choices between sure monetary options and risky gambles both in the gain and loss domains. Each participant played the task twice, either under placebo or the dopamine D 2 /D 3 receptor antagonist sulpiride, in a double-blind counterbalanced design. A prospect theory modelling approach was used to estimate subjective probability weighting and sensitivity to monetary outcomes. Consistent with prospect theory, we found that participants presented a distortion in the subjective weighting of probabilities, i.e., they overweighted low probabilities and underweighted moderate to high probabilities, both in the gain and loss domains. Compared with placebo, sulpiride attenuated this distortion in the gain domain. Across drugs, the groups did not differ in their probability weighting, although gamblers consistently underweighted losing probabilities in the placebo condition. Overall, our results reveal that dopamine D 2 /D 3 receptor antagonism modulates the subjective weighting of probabilities in the gain domain, in the direction of more objective, economically rational decision making.

  11. Dopaminergic Drug Effects on Probability Weighting during Risky Decision Making

    Science.gov (United States)

    Timmer, Monique H. M.; ter Huurne, Niels P.

    2018-01-01

    Abstract Dopamine has been associated with risky decision-making, as well as with pathological gambling, a behavioral addiction characterized by excessive risk-taking behavior. However, the specific mechanisms through which dopamine might act to foster risk-taking and pathological gambling remain elusive. Here we test the hypothesis that this might be achieved, in part, via modulation of subjective probability weighting during decision making. Human healthy controls (n = 21) and pathological gamblers (n = 16) played a decision-making task involving choices between sure monetary options and risky gambles both in the gain and loss domains. Each participant played the task twice, either under placebo or the dopamine D2/D3 receptor antagonist sulpiride, in a double-blind counterbalanced design. A prospect theory modelling approach was used to estimate subjective probability weighting and sensitivity to monetary outcomes. Consistent with prospect theory, we found that participants presented a distortion in the subjective weighting of probabilities, i.e., they overweighted low probabilities and underweighted moderate to high probabilities, both in the gain and loss domains. Compared with placebo, sulpiride attenuated this distortion in the gain domain. Across drugs, the groups did not differ in their probability weighting, although gamblers consistently underweighted losing probabilities in the placebo condition. Overall, our results reveal that dopamine D2/D3 receptor antagonism modulates the subjective weighting of probabilities in the gain domain, in the direction of more objective, economically rational decision making. PMID:29632870

  12. Systematic mapping review about costs and economic evaluations of skin conditions and diseases in the aged.

    Science.gov (United States)

    Lichterfeld-Kottner, Andrea; Hahnel, Elisabeth; Blume-Peytavi, Ulrike; Kottner, Jan

    2017-02-01

    Skin conditions and dermatological diseases associated with advanced age (e.g. fungal infection, dry skin and itch) receive increasingly attention in clinical practice and research. Cost and economic evaluations are important sources to inform priority setting and ressource allocation decisions in healthcare. The economics of skin conditions in aged populations has not been systematically reviewed so far. The aim of this mapping review was to summarize the economic evidence of selected skin conditions in the aged (65 + years). A mapping literature review and evidence summary was conducted. Searches were conducted in data bases Medline and Embase via OVID. Cinahl was searched using EBSCO. References lists of potential eligible studies, reviews, guidelines or other sources were screened for additional literature. For evaluation of methodological quality of full economic analyses the Consensus on Health Economic Criteria (CHEC) checklist was used. Database searches resulted in 1388 records. A total of 270 articles were read in full-text. Thirty-five publications were finally included in the data analysis reporting 38 economic analyses. Ten cost of illness analyses and 26 cost-effectiveness analyses reporting about pressure ulcers, skin tears, pressure ulcers, incontinence associated dermatitis and intertrigo/contact dermatitis/candidiasis treatment and prevention and onychomycosis testing were identified. Limited evidence indicated that low air loss beds were more cost effective than standard beds for prevention of pressure ulcers. Standardized skin care regimens seem to lower the incidence of pressure ulcers, skin tears and IAD but a cost saving effect was not always observed. Findings of this mapping review indicate that there is a paucity of high quality evidence regarding the economic impact of age-associated skin conditions and diseases. Substantial heterogeneity in terms of study design, evaluation perspective, time period, and way of cost estimation was

  13. Probability Distribution of Long-run Indiscriminate Felling of Trees in ...

    African Journals Online (AJOL)

    Bright

    conditionally independent of every prior state given the current state (Obodos, ... of events or experiments in which the probability of occurrence for an event ... represent the exhaustive and mutually exclusive outcomes (states) of a system at.

  14. Demand-specific work ability, poor health and working conditions in middle-aged full-time employees.

    Science.gov (United States)

    Nabe-Nielsen, Kirsten; Thielen, Karsten; Nygaard, Else; Thorsen, Sannie Vester; Diderichsen, Finn

    2014-07-01

    We investigated the prevalence of reduced demand-specific work ability, its association with age, gender, education, poor health, and working conditions, and the interaction between poor health and working conditions regarding reduced demand-specific work ability. We used cross-sectional questionnaire data from 3381 full-time employees responding to questions about vocational education, job demands and social support (working conditions), musculoskeletal pain (MSP) and major depression (MD) (poor health) and seven questions about difficulty managing different job demands (reduced demand-specific work ability). Reduced demand-specific work ability varied from 9% to 19% among the 46-year old and from 11% to 21% among the 56-year old. Age was associated with two, gender with four, and education with all measures of reduced demand-specific work ability. MSP was associated with four and MD was associated with six measures of reduced demand-specific work ability. We found no interaction between working conditions and poor health regarding reduced demand-specific work ability. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  15. Fatigue and Creep Crack Propagation behaviour of Alloy 617 in the Annealed and Aged Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Julian K. Benz; Richard N. Wright

    2013-10-01

    The crack propagation behaviour of Alloy 617 was studied under various conditions. Elevated temperature fatigue and creep-fatigue crack growth experiments were conducted at 650 and 800 degrees C under constant stress intensity (triangle K) conditions and triangular or trapezoidal waveforms at various frequencies on as-received, aged, and carburized material. Environmental conditions included both laboratory air and characteristic VHTR impure helium. As-received Alloy 617 displayed an increase in the crack growth rate (da/dN) as the frequency was decreased in air which indicated a time-dependent contribution component in fatigue crack propagation. Material aged at 650°C did not display any influence on the fatigue crack growth rates nor the increasing trend of crack growth rate with decreasing frequency even though significant microstructural evolution, including y’ (Ni3Al) after short times, occurred during aging. In contrast, carburized Alloy 617 showed an increase in crack growth rates at all frequencies tested compared to the material in the standard annealed condition. Crack growth studies under quasi-constant K (i.e. creep) conditions were also completed at 650 degrees C and a stress intensity of K = 40 MPa9 (square root)m. The results indicate that crack growth is primarily intergranular and increased creep crack growth rates exist in the impure helium environment when compared to the results in laboratory air. Furthermore, the propagation rates (da/dt) continually increased for the duration of the creep crack growth either due to material aging or evolution of a crack tip creep zone. Finally, fatigue crack propagation tests at 800 degrees C on annealed Alloy 617 indicated that crack propagation rates were higher in air than impure helium at the largest frequencies and lowest stress intensities. The rates in helium, however, eventually surpass the rates in air as the frequency is reduced and the stress intensity is decreased which was not observed at 650

  16. Precise Propagation of Upper and Lower Probability Bounds in System P

    OpenAIRE

    Gilio, Angelo

    2000-01-01

    In this paper we consider the inference rules of System P in the framework of coherent imprecise probabilistic assessments. Exploiting our algorithms, we propagate the lower and upper probability bounds associated with the conditional assertions of a given knowledge base, automatically obtaining the precise probability bounds for the derived conclusions of the inference rules. This allows a more flexible and realistic use of System P in default reasoning and provides an exact illustration of ...

  17. The association between chronic conditions and non-agricultural work productivity loss among the middle-aged Chinese population.

    Science.gov (United States)

    Zhang, Wei; Sun, Huiying; Li, Xin

    2018-05-03

    To measure the association between different chronic conditions and non-agricultural work productivity loss among the middle-aged Chinese population. We used 2011, 2013 and 2015 data from the China Health and Retirement Longitudinal Study. The study focused on middle-aged respondents who had the potential to work in the non-agricultural sector. Work productivity loss was measured by non-agricultural work participation and number of absent workdays among those conducting non-agricultural work. Seven different chronic conditions were considered. Heart diseases had the strongest association with lower work participation for men and women. Stomach/digestive disease and arthritis/rheumatism were conditions with the largest incremental absent workdays for men and women, respectively. The associations with non-agricultural work productivity loss varied by chronic conditions, outcomes, and sex. The findings will help motivate chronic condition prevention/management programs and set priorities.

  18. Probability of inadvertent operation of electrical components in harsh environments

    International Nuclear Information System (INIS)

    Knoll, A.

    1989-01-01

    Harsh environment, which means humidity and high temperature, may and will affect unsealed electrical components by causing leakage ground currents in ungrounded direct current systems. The concern in a nuclear power plant is that such harsh environment conditions could cause inadvertent operation of normally deenergized components, which may have a safety-related isolation function. Harsh environment is a common cause failure, and one way to approach the problem is to assume that all the unsealed electrical components will simultaneously and inadvertently energize as a result of the environmental common cause failure. This assumption is unrealistically conservative. Test results indicated that insulating resistences of any terminal block in harsh environments have a random distribution in the range of 1 to 270 kΩ, with a mean value ∼59 kΩ. The objective of this paper is to evaluate a realistic conditional failure probability for inadvertent operation of electrical components in harsh environments. This value will be used thereafter in probabilistic safety evaluations of harsh environment events and will replace both the overconservative common cause probability of 1 and the random failure probability used for mild environments

  19. VOLCANIC RISK ASSESSMENT - PROBABILITY AND CONSEQUENCES

    International Nuclear Information System (INIS)

    G.A. Valentine; F.V. Perry; S. Dartevelle

    2005-01-01

    Risk is the product of the probability and consequences of an event. Both of these must be based upon sound science that integrates field data, experiments, and modeling, but must also be useful to decision makers who likely do not understand all aspects of the underlying science. We review a decision framework used in many fields such as performance assessment for hazardous and/or radioactive waste disposal sites that can serve to guide the volcanological community towards integrated risk assessment. In this framework the underlying scientific understanding of processes that affect probability and consequences drive the decision-level results, but in turn these results can drive focused research in areas that cause the greatest level of uncertainty at the decision level. We review two examples of the determination of volcanic event probability: (1) probability of a new volcano forming at the proposed Yucca Mountain radioactive waste repository, and (2) probability that a subsurface repository in Japan would be affected by the nearby formation of a new stratovolcano. We also provide examples of work on consequences of explosive eruptions, within the framework mentioned above. These include field-based studies aimed at providing data for ''closure'' of wall rock erosion terms in a conduit flow model, predictions of dynamic pressure and other variables related to damage by pyroclastic flow into underground structures, and vulnerability criteria for structures subjected to conditions of explosive eruption. Process models (e.g., multiphase flow) are important for testing the validity or relative importance of possible scenarios in a volcanic risk assessment. We show how time-dependent multiphase modeling of explosive ''eruption'' of basaltic magma into an open tunnel (drift) at the Yucca Mountain repository provides insight into proposed scenarios that include the development of secondary pathways to the Earth's surface. Addressing volcanic risk within a decision

  20. Optical aging observation in suspended core tellurite microstructured fibers under atmospheric conditions

    Science.gov (United States)

    Strutynski, C.; Mouawad, O.; Picot-Clémente, J.; Froidevaux, P.; Désévédavy, F.; Gadret, G.; Jules, J.-C.; Kibler, B.; Smektala, F.

    2017-11-01

    Tellurite glasses are good candidates for the development of broadband supercontinuum (SC) laser sources in the 1-5 μm range. At the moment, beside very few exceptions, SC generation in TeO2-based microstructured optical fibers (MOFs) is limited to 3 μm in the mid-infrared (MIR). We present here an observation of an optical aging occurring in six-hole suspended-core tellurite MOFs. When exposed to atmospheric conditions, such fibers show an alteration of their transmission between 3 and 4 μm. This aging phenomenon leads to the growth of strong additional losses in this wavelengths range over time. Impact of the transmission degradation on spectral broadening is studied through numerical simulations of SC generation.

  1. Learning-based encoding with soft assignment for age estimation under unconstrained imaging conditions

    NARCIS (Netherlands)

    Alnajar, F.; Shan, C.; Gevers, T.; Geusebroek, J.M.

    2012-01-01

    In this paper we propose to adopt a learning-based encoding method for age estimation under unconstrained imaging conditions. A similar approach [Cao et al., 2010] is applied to face recognition in real-life face images. However, the feature vectors are encoded in hard manner i.e. each feature

  2. Influence of aging condition and reversion austenite on fatigue property of the 300 grade 18Ni maraging steel

    International Nuclear Information System (INIS)

    Moriyama, Michihiko; Takaki, Setsuo; Kawagoishi, Norio

    2000-01-01

    The influence of aging condition on fatigue strength of the 300 grade 18Ni maraging steel has been investigated in relation to the behavior of age hardening and the formation of reversion austenite. In this study, rotating bending fatigue tests were performed for three series of specimens with different aging condition; as solution-treated without aging, aged for various time at 753 K which is the temperature applied for the industrial aging treatment, and over-aged to form a small amount of reversion austenite. Effect of reversion austenite on fatigue strength was examined using specimens with the same static strength which had been controlled by varying aging temperature and time, namely under-aging or over-aging. The main results obtained are as follows. (1) In the case of 753 K aging, the fatigue limits of specimens aged for 11 ks to 48 ks were nearly the same value, although an under-aged (2.8 ks) specimen has as much lower value as a solution-treated specimen without aging treatment. (2) A small amount of reversion austenite is effective for increasing fatigue resistance. For instance, 2 vol% of austenite was enough for improving fatigue limit of the maraging steel used, from 580 MPa to 640 MPa at the same hardness level of Hv 610. (author)

  3. Influence of outdoor games on functional condition of the respiratory system at girls of the younger school age

    Directory of Open Access Journals (Sweden)

    Оlena Potapova

    2016-10-01

    Full Text Available Purpose: to study influence of outdoor games on functional condition of the respiratory system of girls of the younger school age in the groups of 6–8 and 9–10 years old. Material & Methods: the problem of functional condition of external breath at girls of the younger school age (in the age groups of 6–8 and 9–10 years old, who were divided into the control group (CG in number of 32persons (CS No. 58 and the experimental (EG in number of 29 persons (OTEC No. 109 of Zaporozhe, is considered. Results: it is defined that the studied girls of both groups at the beginning of the research had mainly below average and average levels of functional condition of the system of external breath. Conclusions: the effective impact of outdoor games on functional condition of the whole organism in general and on the system of external breath, in particular, at girls of the experimental group in comparison with the studied girls of the same age of the control group is proved experimentally. Application of the large number of various outdoor games allowed diversifying the program of training at physical education classes emotionally and physically, than promoted the activation of functions of the whole organism of girls of the younger school age.

  4. Probability of detection of clinical seizures using heart rate changes.

    Science.gov (United States)

    Osorio, Ivan; Manly, B F J

    2015-08-01

    Heart rate-based seizure detection is a viable complement or alternative to ECoG/EEG. This study investigates the role of various biological factors on the probability of clinical seizure detection using heart rate. Regression models were applied to 266 clinical seizures recorded from 72 subjects to investigate if factors such as age, gender, years with epilepsy, etiology, seizure site origin, seizure class, and data collection centers, among others, shape the probability of EKG-based seizure detection. Clinical seizure detection probability based on heart rate changes, is significantly (pprobability of detecting clinical seizures (>0.8 in the majority of subjects) using heart rate is highest for complex partial seizures, increases with a patient's years with epilepsy, is lower for females than for males and is unrelated to the side of hemisphere origin. Clinical seizure detection probability using heart rate is multi-factorially dependent and sufficiently high (>0.8) in most cases to be clinically useful. Knowledge of the role that these factors play in shaping said probability will enhance its applicability and usefulness. Heart rate is a reliable and practical signal for extra-cerebral detection of clinical seizures originating from or spreading to central autonomic network structures. Copyright © 2015 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  5. Characteristics of Adults with Down Syndrome: prevalence of age-related conditions

    Directory of Open Access Journals (Sweden)

    Angelo eCarfì

    2014-12-01

    Full Text Available Introduction. In the last decades, life expectancy of persons with Down syndrome (DS has dramatically increased and it is estimated that they will be living as long as the general population within a generation. Despite being included among the progeroid syndromes, because of the presence of features typically observed in older adults, DS is still regarded as a disease of pediatric interest. Because limited knowledge is available on the clinical characteristics of adults with DS, this study aimed to assess clinical and non-clinical features of this population and to describe similarities to the geriatric population. Methods. In this study, we described 60 adults with DS evaluated at the Day Hospital of the Geriatric Department of the Policlinico A. Gemelli, Università Cattolica del Sacro Cuore in Rome. Individuals were assessed through a standardized protocol. Results. The mean age of study participants was 38 years (range, 18 to 58 years and 42 (70.0% were women. Geriatric conditions were highly prevalent: severe cognitive impairment was diagnosed in 39 (65.0% participants, behavioral symptoms were present in 25 (41.7% and functional impairment in 23 (38.3%. Six (10.0% participants lived in institutions and 11 (18.3% were diagnosed as obese. The mean number of drugs used was 2.4; use of psychotropic drugs was highly prevalent. The most common chronic diseases were thyroid problems (44, 73.3%, followed by mood disorders (19, 31.7%, osteoporosis (18, 30.0% and cardiac problems (10, 16.7%. Geriatric conditions and chronic diseases were more prevalent among participants aged ≥40 years. Conclusions. Several similarities between older adults and adults with DS were observed. Comorbidities, geriatric conditions, cognitive and functional deficits and social problems are highly prevalent in both populations, contributing to the high complexity of these patients’ assessment and treatment.

  6. Age and Sex Variation In Prevalence Of Chronic Medical Conditions In Older Residents of U.S. Nursing Homes

    Science.gov (United States)

    Moore, Kelly L.; Boscardin, W. John; Steinman, Michael A.; Schwartz, Janice B.

    2012-01-01

    OBJECTIVES To investigate patterns in prevalences of chronic medical conditions over the agespan of long-term stay nursing home residents and between the sexes with data from the 2004 National Nursing Home Survey (NNHS). DESIGN Retrospective, cross-sectional study. SETTING U.S. nursing homes. PARTICIPANTS Nationally representative sample comprising 11,788 long-term stay residents (3003 (25%) men and 8785 women) aged 65 years or older. MEASUREMENTS Clinical Classifications Software (CCS) was used to group ICD-9 codes to identify the 20 most prevalent chronic medical conditions. SAS survey procedures were used to account for design effects of stratification and clustering to generate nationally representative estimates of prevalences of medical conditions. RESULTS Average age was 84 y, with women older than men (85 vs. 81, p=0.02) with 67% of women ages 80–95. Women required more ADL assistance. The most frequent chronic medical conditions were hypertension (53, 56%: men, women), dementia (45, 52%), depression (31, 37%), arthritis (26, 35%), diabetes mellitus (26, 23%), gastrointestinal reflux -GERD (23, 23%), atherosclerosis (24, 20%), congestive heart failure -CHF (18, 21%), cerebrovascular disease (24, 19%) and anemia (17, 20%). Sex differences in prevalences existed for all but constipation, GERD, and hypertension. Diabetes, cerebrovascular disease, and lipid disorders decreased with age in men and women. Atrial fibrillation, anemia, arthritis, CHF, and dementia, and thyroid disease increased with age in both men and women. Age-related patterns differed between the sexes for diabetes, hypertension, and Parkinson’s disease. CONCLUSION The profile of chronic medical conditions varies over the agespan of nursing home residents and differs between men and women. This knowledge should guide educational and care efforts in long-term care. PMID:22463062

  7. On estimating the fracture probability of nuclear graphite components

    International Nuclear Information System (INIS)

    Srinivasan, Makuteswara

    2008-01-01

    The properties of nuclear grade graphites exhibit anisotropy and could vary considerably within a manufactured block. Graphite strength is affected by the direction of alignment of the constituent coke particles, which is dictated by the forming method, coke particle size, and the size, shape, and orientation distribution of pores in the structure. In this paper, a Weibull failure probability analysis for components is presented using the American Society of Testing Materials strength specification for nuclear grade graphites for core components in advanced high-temperature gas-cooled reactors. The risk of rupture (probability of fracture) and survival probability (reliability) of large graphite blocks are calculated for varying and discrete values of service tensile stresses. The limitations in these calculations are discussed from considerations of actual reactor environmental conditions that could potentially degrade the specification properties because of damage due to complex interactions between irradiation, temperature, stress, and variability in reactor operation

  8. Philosophical theories of probability

    CERN Document Server

    Gillies, Donald

    2000-01-01

    The Twentieth Century has seen a dramatic rise in the use of probability and statistics in almost all fields of research. This has stimulated many new philosophical ideas on probability. Philosophical Theories of Probability is the first book to present a clear, comprehensive and systematic account of these various theories and to explain how they relate to one another. Gillies also offers a distinctive version of the propensity theory of probability, and the intersubjective interpretation, which develops the subjective theory.

  9. An attempt to model the probability of growth and aflatoxin B1 production of Aspergillus flavus under non-isothermal conditions in pistachio nuts.

    Science.gov (United States)

    Aldars-García, Laila; Ramos, Antonio J; Sanchis, Vicente; Marín, Sonia

    2015-10-01

    Human exposure to aflatoxins in foods is of great concern. The aim of this work was to use predictive mycology as a strategy to mitigate the aflatoxin burden in pistachio nuts postharvest. The probability of growth and aflatoxin B1 (AFB1) production of aflatoxigenic Aspergillus flavus, isolated from pistachio nuts, under static and non-isothermal conditions was studied. Four theoretical temperature scenarios, including temperature levels observed in pistachio nuts during shipping and storage, were used. Two types of inoculum were included: a cocktail of 25 A. flavus isolates and a single isolate inoculum. Initial water activity was adjusted to 0.87. Logistic models, with temperature and time as explanatory variables, were fitted to the probability of growth and AFB1 production under a constant temperature. Subsequently, they were used to predict probabilities under non-isothermal scenarios, with levels of concordance from 90 to 100% in most of the cases. Furthermore, the presence of AFB1 in pistachio nuts could be correctly predicted in 70-81 % of the cases from a growth model developed in pistachio nuts, and in 67-81% of the cases from an AFB1 model developed in pistachio agar. The information obtained in the present work could be used by producers and processors to predict the time for AFB1 production by A. flavus on pistachio nuts during transport and storage. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Toxicity of functional nano-micro zinc oxide tetrapods: impact of cell culture conditions, cellular age and material properties.

    Science.gov (United States)

    Papavlassopoulos, Heike; Mishra, Yogendra K; Kaps, Sören; Paulowicz, Ingo; Abdelaziz, Ramzy; Elbahri, Mady; Maser, Edmund; Adelung, Rainer; Röhl, Claudia

    2014-01-01

    With increasing production and applications of nanostructured zinc oxide, e.g., for biomedical and consumer products, the question of safety is getting more and more important. Different morphologies of zinc oxide structures have been synthesized and accordingly investigated. In this study, we have particularly focused on nano-micro ZnO tetrapods (ZnO-T), because their large scale fabrication has been made possible by a newly introduced flame transport synthesis approach which will probably lead to several new applications. Moreover, ZnO-T provide a completely different morphology then classical spherical ZnO nanoparticles. To get a better understanding of parameters that affect the interactions between ZnO-T and mammalian cells, and thus their biocompatibility, we have examined the impact of cell culture conditions as well as of material properties on cytotoxicity. Our results demonstrate that the cell density of fibroblasts in culture along with their age, i.e., the number of preceding cell divisions, strongly affect the cytotoxic potency of ZnO-T. Concerning the material properties, the toxic potency of ZnO-T is found to be significantly lower than that of spherical ZnO nanoparticles. Furthermore, the morphology of the ZnO-T influenced cellular toxicity in contrast to surface charges modified by UV illumination or O2 treatment and to the material age. Finally, we have observed that direct contact between tetrapods and cells increases their toxicity compared to transwell culture models which allow only an indirect effect via released zinc ions. The results reveal several parameters that can be of importance for the assessment of ZnO-T toxicity in cell cultures and for particle development.

  11. Clinical Features in a Danish Population-Based Cohort of Probable Multiple System Atrophy Patients

    DEFF Research Database (Denmark)

    Starhof, Charlotte; Korbo, Lise; Lassen, Christina Funch

    2016-01-01

    Background: Multiple system atrophy (MSA) is a rare, sporadic and progressive neurodegenerative disorder. We aimed to describe the clinical features of Danish probable MSA patients, evaluate their initial response to dopaminergic therapy and examine mortality. Methods: From the Danish National...... the criteria for probable MSA. We recorded clinical features, examined differences by MSA subtype and used Kaplan-Meier survival analysis to examine mortality. Results: The mean age at onset of patients with probable MSA was 60.2 years (range 36-75 years) and mean time to wheelchair dependency was 4.7 years...

  12. How Life History Can Sway the Fixation Probability of Mutants

    Science.gov (United States)

    Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

    2016-01-01

    In this work, we study the effects of demographic structure on evolutionary dynamics when selection acts on reproduction, survival, or both. In contrast to the previously discovered pattern that the fixation probability of a neutral mutant decreases while the population becomes younger, we show that a mutant with a constant selective advantage may have a maximum or a minimum of the fixation probability in populations with an intermediate fraction of young individuals. This highlights the importance of life history and demographic structure in studying evolutionary dynamics. We also illustrate the fundamental differences between selection on reproduction and selection on survival when age structure is present. In addition, we evaluate the relative importance of size and structure of the population in determining the fixation probability of the mutant. Our work lays the foundation for also studying density- and frequency-dependent effects in populations when demographic structures cannot be neglected. PMID:27129737

  13. Intelligence, Belief in the Paranormal, Knowledge of Probability and Aging

    Science.gov (United States)

    Stuart-Hamilton, Ian; Nayak, Laxman; Priest, Lee

    2006-01-01

    In young adults, preparedness to accept improbable events as planned rather than due to chance is predictive of the level of belief in the paranormal, possibly underpinned by lower intelligence levels (Musch and Ehrenberg, 2002). The present study, using a sample of 73 older participants aged 60-84 years failed to find any relationship between…

  14. Stress corrosion cracking of age-hardenable nickel-base alloys in LWR-conditions

    International Nuclear Information System (INIS)

    Kekkonen, T.; Haenninen, H.

    1985-01-01

    At present it seems that the microstructure most resistant to stress corrosion cracking (SCC) in high temperature water is obtained by a solution annealing treatment at a relatively high temperature (appr. 1100 deg C) followed by water quenching and a single aging treatment (appr. 700 deg C/20 h). This should produce a microstructure with a high M 23 Cc 6 :MC ratio, semi-continous coherent M 23 C 6 precipitation, and an evenly distributed gamma prime in the matrix. However, since the actual mechanism of SCC in age-hardenable Ni-base alloys is unclear, the microstructural features resulting in the good resistance to SCC cannot be specified. Furthermore, the possible microstructural changes caused by prolonged use in LWR-conditions are unknown

  15. Influence of Malnutrition on Adverse Outcome in Children with Confirmed or Probable Viral Encephalitis: A Prospective Observational Study

    Directory of Open Access Journals (Sweden)

    Priyanka Singh

    2015-01-01

    Full Text Available A prospective observational study was conducted in a tertiary care teaching hospital from August 2008 to August 2009 to explore the independent predictors of adverse outcome in the patients with confirmed/probable viral encephalitis. The primary outcome variable was the incidence of adverse outcomes defined as death or severe neurological deficit such as loss of speech, motor deficits, behavioural problems, blindness, and cognitive impairment. Patients with confirmed or probable viral encephalitis were classified into two groups based on their Z-score of weight-for-age as per WHO growth charts. Group I. Patients with confirmed or probable viral encephalitis with weight-for-age (W/A Z-scores below −2SD were classified as undernourished. Group II. Patients with confirmed or probable viral encephalitis were classified as having normal nutritional status (weight-for-age Z-score >−2SD. A total of 114 patients were classified as confirmed or probable viral encephalitis based on detailed investigations. On multivariate logistic regression, undernutrition (adjusted OR: 5.05; 95% CI: 1.92 to 13.44 and requirement of ventilation (adjusted OR: 6.75; 95% CI: 3.63 to 77.34 were independent predictors of adverse outcomes in these patients. Thus, the results from our study highlight that the association between undernutrition and adverse outcome could be extended to the patients with confirmed/probable viral encephalitis.

  16. The conditions of believe and unbelieve in a secular Age

    Directory of Open Access Journals (Sweden)

    Juan Manuel Cincunegui

    2014-05-01

    Full Text Available In A Secular Age the Canadian philosopher Charles Taylor offered an analytical description and a genealogy of the current conditions of belief and unbelief in the North Atlantic contemporary societies. He encouraged as well a set of similar investigations in other cultural settings that are affected by the processes of modernization. He argues about the existence of ‘alternative modernities’ each one of them facing critically the univocal sociological theories of modernity and secularization that interpreted as universal the process of disenchantment occurred in the West and the setbacks with regard to the presence of religion in the public sphere and religious practice in some contemporary Western societies

  17. Finding upper bounds for software failure probabilities - experiments and results

    International Nuclear Information System (INIS)

    Kristiansen, Monica; Winther, Rune

    2005-09-01

    This report looks into some aspects of using Bayesian hypothesis testing to find upper bounds for software failure probabilities. In the first part, the report evaluates the Bayesian hypothesis testing approach for finding upper bounds for failure probabilities of single software components. The report shows how different choices of prior probability distributions for a software component's failure probability influence the number of tests required to obtain adequate confidence in a software component. In the evaluation, both the effect of the shape of the prior distribution as well as one's prior confidence in the software component were investigated. In addition, different choices of prior probability distributions are discussed based on their relevance in a software context. In the second part, ideas on how the Bayesian hypothesis testing approach can be extended to assess systems consisting of multiple software components are given. One of the main challenges when assessing systems consisting of multiple software components is to include dependency aspects in the software reliability models. However, different types of failure dependencies between software components must be modelled differently. Identifying different types of failure dependencies are therefore an important condition for choosing a prior probability distribution, which correctly reflects one's prior belief in the probability for software components failing dependently. In this report, software components include both general in-house software components, as well as pre-developed software components (e.g. COTS, SOUP, etc). (Author)

  18. Probability for statisticians

    CERN Document Server

    Shorack, Galen R

    2017-01-01

    This 2nd edition textbook offers a rigorous introduction to measure theoretic probability with particular attention to topics of interest to mathematical statisticians—a textbook for courses in probability for students in mathematical statistics. It is recommended to anyone interested in the probability underlying modern statistics, providing a solid grounding in the probabilistic tools and techniques necessary to do theoretical research in statistics. For the teaching of probability theory to post graduate statistics students, this is one of the most attractive books available. Of particular interest is a presentation of the major central limit theorems via Stein's method either prior to or alternative to a characteristic function presentation. Additionally, there is considerable emphasis placed on the quantile function as well as the distribution function. The bootstrap and trimming are both presented. Martingale coverage includes coverage of censored data martingales. The text includes measure theoretic...

  19. Concurrent choice for social interaction and amphetamine using conditioned place preference in rats: effects of age and housing condition.

    Science.gov (United States)

    Yates, Justin R; Beckmann, Joshua S; Meyer, Andrew C; Bardo, Michael T

    2013-05-01

    Social interaction can serve as a natural reward that attenuates drug reward in rats; however, it is unknown if age or housing conditions alter the choice between social interaction and drug. Individually- and pair-housed adolescent and adult male rats were tested using conditioned place preference (CPP) in separate experiments in which: (1) social interaction was conditioned against no social interaction; (2) amphetamine (AMPH; 1mg/kg, s.c.) was conditioned against saline; or (3) social interaction was conditioned against AMPH. Social interaction CPP was obtained only in individually-housed adolescents, whereas AMPH CPP was obtained in both individually-housed adolescents and adults; however, the effect of AMPH was not statistically significant in pair-housed adults. When allowed to choose concurrently between compartments paired with either social interaction or AMPH, individually-housed adolescents preferred the compartment paired with social interaction, whereas pair-housed adolescents preferred the compartment paired with AMPH. Regardless of housing condition, adults showed a similar preference for the compartments paired with either social interaction or AMPH. Although some caution is needed in interpreting cross-experiment comparisons, the overall results suggest that individually-housed adolescents were most sensitive to the rewarding effect of social interaction, and this hypersensitivity to social reward effectively competed with AMPH reward. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Brain aging and Aβ₁₋₄₂ neurotoxicity converge via deterioration in autophagy-lysosomal system: a conditional Drosophila model linking Alzheimer's neurodegeneration with aging.

    Science.gov (United States)

    Ling, Daijun; Salvaterra, Paul M

    2011-02-01

    Aging is known to be the most prominent risk factor for Alzheimer's disease (AD); however, the underlying mechanism linking brain aging with AD pathogenesis remains unknown. The expression of human amyloid beta 42 peptide (Aβ₁₋₄₂), but not Aβ₁₋₄₀ in Drosophila brain induces an early onset and progressive autophagy-lysosomal neuropathology. Here we show that the natural process of brain aging also accompanies a chronic and late-onset deterioration of neuronal autophagy-lysosomal system. This process is characterized by accumulation of dysfunctional autophagy-lysosomal vesicles, a compromise of these vesicles leading to damage of intracellular membranes and organelles, necrotic-like intraneuronal destruction and neurodegeneration. In addition, conditional activation of neuronal autophagy in young animals is protective while late activation is deleterious for survival. Intriguingly, conditional Aβ₁₋₄₂ expression limited to young animals exacerbates the aging process to a greater extent than Aβ₁₋₄₂ expression in old animals. These data suggest that the neuronal autophagy-lysosomal system may shift from a functional and protective state to a pathological and deleterious state either during brain aging or via Aβ₁₋₄₂ neurotoxicity. A chronic deterioration of the neuronal autophagy-lysosomal system is likely to be a key event in transitioning from normal brain aging to pathological aging leading to Alzheimer's neurodegeneration.

  1. A brief introduction to probability.

    Science.gov (United States)

    Di Paola, Gioacchino; Bertani, Alessandro; De Monte, Lavinia; Tuzzolino, Fabio

    2018-02-01

    The theory of probability has been debated for centuries: back in 1600, French mathematics used the rules of probability to place and win bets. Subsequently, the knowledge of probability has significantly evolved and is now an essential tool for statistics. In this paper, the basic theoretical principles of probability will be reviewed, with the aim of facilitating the comprehension of statistical inference. After a brief general introduction on probability, we will review the concept of the "probability distribution" that is a function providing the probabilities of occurrence of different possible outcomes of a categorical or continuous variable. Specific attention will be focused on normal distribution that is the most relevant distribution applied to statistical analysis.

  2. Conditional Probabilities of Large Earthquake Sequences in California from the Physics-based Rupture Simulator RSQSim

    Science.gov (United States)

    Gilchrist, J. J.; Jordan, T. H.; Shaw, B. E.; Milner, K. R.; Richards-Dinger, K. B.; Dieterich, J. H.

    2017-12-01

    Within the SCEC Collaboratory for Interseismic Simulation and Modeling (CISM), we are developing physics-based forecasting models for earthquake ruptures in California. We employ the 3D boundary element code RSQSim (Rate-State Earthquake Simulator of Dieterich & Richards-Dinger, 2010) to generate synthetic catalogs with tens of millions of events that span up to a million years each. This code models rupture nucleation by rate- and state-dependent friction and Coulomb stress transfer in complex, fully interacting fault systems. The Uniform California Earthquake Rupture Forecast Version 3 (UCERF3) fault and deformation models are used to specify the fault geometry and long-term slip rates. We have employed the Blue Waters supercomputer to generate long catalogs of simulated California seismicity from which we calculate the forecasting statistics for large events. We have performed probabilistic seismic hazard analysis with RSQSim catalogs that were calibrated with system-wide parameters and found a remarkably good agreement with UCERF3 (Milner et al., this meeting). We build on this analysis, comparing the conditional probabilities of sequences of large events from RSQSim and UCERF3. In making these comparisons, we consider the epistemic uncertainties associated with the RSQSim parameters (e.g., rate- and state-frictional parameters), as well as the effects of model-tuning (e.g., adjusting the RSQSim parameters to match UCERF3 recurrence rates). The comparisons illustrate how physics-based rupture simulators might assist forecasters in understanding the short-term hazards of large aftershocks and multi-event sequences associated with complex, multi-fault ruptures.

  3. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2013-01-01

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications. The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended...

  4. Probability of satellite collision

    Science.gov (United States)

    Mccarter, J. W.

    1972-01-01

    A method is presented for computing the probability of a collision between a particular artificial earth satellite and any one of the total population of earth satellites. The collision hazard incurred by the proposed modular Space Station is assessed using the technique presented. The results of a parametric study to determine what type of satellite orbits produce the greatest contribution to the total collision probability are presented. Collision probability for the Space Station is given as a function of Space Station altitude and inclination. Collision probability was also parameterized over miss distance and mission duration.

  5. Probability and Measure

    CERN Document Server

    Billingsley, Patrick

    2012-01-01

    Praise for the Third Edition "It is, as far as I'm concerned, among the best books in math ever written....if you are a mathematician and want to have the top reference in probability, this is it." (Amazon.com, January 2006) A complete and comprehensive classic in probability and measure theory Probability and Measure, Anniversary Edition by Patrick Billingsley celebrates the achievements and advancements that have made this book a classic in its field for the past 35 years. Now re-issued in a new style and format, but with the reliable content that the third edition was revered for, this

  6. Experimental Probability in Elementary School

    Science.gov (United States)

    Andrew, Lane

    2009-01-01

    Concepts in probability can be more readily understood if students are first exposed to probability via experiment. Performing probability experiments encourages students to develop understandings of probability grounded in real events, as opposed to merely computing answers based on formulae.

  7. Does probability of occurrence relate to population dynamics?

    Science.gov (United States)

    Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H; Georges, Damien; Dullinger, Stefan; Eckhart, Vincent M; Edwards, Thomas C; Gravel, Dominique; Kunstler, Georges; Merow, Cory; Moore, Kara; Piedallu, Christian; Vissault, Steve; Zimmermann, Niklaus E; Zurell, Damaris; Schurr, Frank M

    2014-12-01

    Hutchinson defined species' realized niche as the set of environmental conditions in which populations can persist in the presence of competitors. In terms of demography, the realized niche corresponds to the environments where the intrinsic growth rate ( r ) of populations is positive. Observed species occurrences should reflect the realized niche when additional processes like dispersal and local extinction lags do not have overwhelming effects. Despite the foundational nature of these ideas, quantitative assessments of the relationship between range-wide demographic performance and occurrence probability have not been made. This assessment is needed both to improve our conceptual understanding of species' niches and ranges and to develop reliable mechanistic models of species geographic distributions that incorporate demography and species interactions. The objective of this study is to analyse how demographic parameters (intrinsic growth rate r and carrying capacity K ) and population density ( N ) relate to occurrence probability ( P occ ). We hypothesized that these relationships vary with species' competitive ability. Demographic parameters, density, and occurrence probability were estimated for 108 tree species from four temperate forest inventory surveys (Québec, Western US, France and Switzerland). We used published information of shade tolerance as indicators of light competition strategy, assuming that high tolerance denotes high competitive capacity in stable forest environments. Interestingly, relationships between demographic parameters and occurrence probability did not vary substantially across degrees of shade tolerance and regions. Although they were influenced by the uncertainty in the estimation of the demographic parameters, we found that r was generally negatively correlated with P occ , while N, and for most regions K, was generally positively correlated with P occ . Thus, in temperate forest trees the regions of highest occurrence

  8. Recursive recovery of Markov transition probabilities from boundary value data

    Energy Technology Data Exchange (ETDEWEB)

    Patch, Sarah Kathyrn [Univ. of California, Berkeley, CA (United States)

    1994-04-01

    In an effort to mathematically describe the anisotropic diffusion of infrared radiation in biological tissue Gruenbaum posed an anisotropic diffusion boundary value problem in 1989. In order to accommodate anisotropy, he discretized the temporal as well as the spatial domain. The probabilistic interpretation of the diffusion equation is retained; radiation is assumed to travel according to a random walk (of sorts). In this random walk the probabilities with which photons change direction depend upon their previous as well as present location. The forward problem gives boundary value data as a function of the Markov transition probabilities. The inverse problem requires finding the transition probabilities from boundary value data. Problems in the plane are studied carefully in this thesis. Consistency conditions amongst the data are derived. These conditions have two effects: they prohibit inversion of the forward map but permit smoothing of noisy data. Next, a recursive algorithm which yields a family of solutions to the inverse problem is detailed. This algorithm takes advantage of all independent data and generates a system of highly nonlinear algebraic equations. Pluecker-Grassmann relations are instrumental in simplifying the equations. The algorithm is used to solve the 4 x 4 problem. Finally, the smallest nontrivial problem in three dimensions, the 2 x 2 x 2 problem, is solved.

  9. The Cabin Crew Blues. Middle-aged Cabin Attendants and Their Working Conditions

    Directory of Open Access Journals (Sweden)

    Ann Bergman

    2015-12-01

    Full Text Available This article examines how an airline company uses the labor of a group of middle-aged cabin attendants in an industry increasingly characterized by deregulation and competiveness. The study was based on in-depth interviews with seven women, all with between 24 and 30 years of work experience as cabin attendants. The article focuses on the women’s working conditions and well-being and the analysis reveals three key aspects—intensification of work, vulnerability, and aging—that affect the cabin attendants’ experiences and emotions in relation to the work. It is at the intersection of these three aspects that the cabin attendants’ concerns must be understood. The study’s findings indicated that positive emotions such as job satisfaction and commitment have diminished because of exploitative and otherwise poor working conditions. Taking the cabin attendants’ concerns as its point of departure, the article shows that there is a need to move away from a discussion about emotional labor toward a discussion of working conditions.

  10. Probabilities in physics

    CERN Document Server

    Hartmann, Stephan

    2011-01-01

    Many results of modern physics--those of quantum mechanics, for instance--come in a probabilistic guise. But what do probabilistic statements in physics mean? Are probabilities matters of objective fact and part of the furniture of the world, as objectivists think? Or do they only express ignorance or belief, as Bayesians suggest? And how are probabilistic hypotheses justified and supported by empirical evidence? Finally, what does the probabilistic nature of physics imply for our understanding of the world? This volume is the first to provide a philosophical appraisal of probabilities in all of physics. Its main aim is to make sense of probabilistic statements as they occur in the various physical theories and models and to provide a plausible epistemology and metaphysics of probabilities. The essays collected here consider statistical physics, probabilistic modelling, and quantum mechanics, and critically assess the merits and disadvantages of objectivist and subjectivist views of probabilities in these fie...

  11. Probability an introduction

    CERN Document Server

    Grimmett, Geoffrey

    2014-01-01

    Probability is an area of mathematics of tremendous contemporary importance across all aspects of human endeavour. This book is a compact account of the basic features of probability and random processes at the level of first and second year mathematics undergraduates and Masters' students in cognate fields. It is suitable for a first course in probability, plus a follow-up course in random processes including Markov chains. A special feature is the authors' attention to rigorous mathematics: not everything is rigorous, but the need for rigour is explained at difficult junctures. The text is enriched by simple exercises, together with problems (with very brief hints) many of which are taken from final examinations at Cambridge and Oxford. The first eight chapters form a course in basic probability, being an account of events, random variables, and distributions - discrete and continuous random variables are treated separately - together with simple versions of the law of large numbers and the central limit th...

  12. Evaluation of nuclear power plant component failure probability and core damage probability using simplified PSA model

    International Nuclear Information System (INIS)

    Shimada, Yoshio

    2000-01-01

    It is anticipated that the change of frequency of surveillance tests, preventive maintenance or parts replacement of safety related components may cause the change of component failure probability and result in the change of core damage probability. It is also anticipated that the change is different depending on the initiating event frequency or the component types. This study assessed the change of core damage probability using simplified PSA model capable of calculating core damage probability in a short time period, which is developed by the US NRC to process accident sequence precursors, when various component's failure probability is changed between 0 and 1, or Japanese or American initiating event frequency data are used. As a result of the analysis, (1) It was clarified that frequency of surveillance test, preventive maintenance or parts replacement of motor driven pumps (high pressure injection pumps, residual heat removal pumps, auxiliary feedwater pumps) should be carefully changed, since the core damage probability's change is large, when the base failure probability changes toward increasing direction. (2) Core damage probability change is insensitive to surveillance test frequency change, since the core damage probability change is small, when motor operated valves and turbine driven auxiliary feed water pump failure probability changes around one figure. (3) Core damage probability change is small, when Japanese failure probability data are applied to emergency diesel generator, even if failure probability changes one figure from the base value. On the other hand, when American failure probability data is applied, core damage probability increase is large, even if failure probability changes toward increasing direction. Therefore, when Japanese failure probability data is applied, core damage probability change is insensitive to surveillance tests frequency change etc. (author)

  13. Unbiased multi-fidelity estimate of failure probability of a free plane jet

    Science.gov (United States)

    Marques, Alexandre; Kramer, Boris; Willcox, Karen; Peherstorfer, Benjamin

    2017-11-01

    Estimating failure probability related to fluid flows is a challenge because it requires a large number of evaluations of expensive models. We address this challenge by leveraging multiple low fidelity models of the flow dynamics to create an optimal unbiased estimator. In particular, we investigate the effects of uncertain inlet conditions in the width of a free plane jet. We classify a condition as failure when the corresponding jet width is below a small threshold, such that failure is a rare event (failure probability is smaller than 0.001). We estimate failure probability by combining the frameworks of multi-fidelity importance sampling and optimal fusion of estimators. Multi-fidelity importance sampling uses a low fidelity model to explore the parameter space and create a biasing distribution. An unbiased estimate is then computed with a relatively small number of evaluations of the high fidelity model. In the presence of multiple low fidelity models, this framework offers multiple competing estimators. Optimal fusion combines all competing estimators into a single estimator with minimal variance. We show that this combined framework can significantly reduce the cost of estimating failure probabilities, and thus can have a large impact in fluid flow applications. This work was funded by DARPA.

  14. Dual Diagnosis and Suicide Probability in Poly-Drug Users.

    Science.gov (United States)

    Youssef, Ismail M; Fahmy, Magda T; Haggag, Wafaa L; Mohamed, Khalid A; Baalash, Amany A

    2016-02-01

    To determine the frequency of suicidal thoughts and suicidal probability among poly-substance abusers in Saudi population, and to examine the relation between dual diagnosis and suicidal thoughts. Case control study. Al-Baha Psychiatric Hospital, Saudi Arabia, from May 2011 to June 2012. Participants were 239 subjects, aged 18 - 45 years. We reviewed 122 individuals who fulfilled the DSM-IV-TR criteria of substance abuse for two or more substances, and their data were compared with that collected from 117 control persons. Suicidal cases were highly present among poly-substance abusers 64.75%. Amphetamine and cannabis were the most abused substances, (87.7% and 70.49%, respectively). Astatistically significant association with suicidality was found with longer duration of substance abuse (p Suicidal cases showed significant higher scores (p suicide probability scale and higher scores in Beck depressive inventory (p Abusing certain substances for long duration, in addition to comorbid psychiatric disorders especially with disturbed-mood element, may trigger suicidal thoughts in poly-substance abusers. Depression and suicide probability is common consequences of substance abuse.

  15. Probability analysis of MCO over-pressurization during staging

    International Nuclear Information System (INIS)

    Pajunen, A.L.

    1997-01-01

    The purpose of this calculation is to determine the probability of Multi-Canister Overpacks (MCOs) over-pressurizing during staging at the Canister Storage Building (CSB). Pressurization of an MCO during staging is dependent upon changes to the MCO gas temperature and the build-up of reaction products during the staging period. These effects are predominantly limited by the amount of water that remains in the MCO following cold vacuum drying that is available for reaction during staging conditions. Because of the potential for increased pressure within an MCO, provisions for a filtered pressure relief valve and rupture disk have been incorporated into the MCO design. This calculation provides an estimate of the frequency that an MCO will contain enough water to pressurize beyond the limits of these design features. The results of this calculation will be used in support of further safety analyses and operational planning efforts. Under the bounding steady state CSB condition assumed for this analysis, an MCO must contain less than 1.6 kg (3.7 lbm) of water available for reaction to preclude actuation of the pressure relief valve at 100 psid. To preclude actuation of the MCO rupture disk at 150 psid, an MCO must contain less than 2.5 kg (5.5 lbm) of water available for reaction. These limits are based on the assumption that hydrogen generated by uranium-water reactions is the sole source of gas produced within the MCO and that hydrates in fuel particulate are the primary source of water available for reactions during staging conditions. The results of this analysis conclude that the probability of the hydrate water content of an MCO exceeding 1.6 kg is 0.08 and the probability that it will exceed 2.5 kg is 0.01. This implies that approximately 32 of 400 staged MCOs may experience pressurization to the point where the pressure relief valve actuates. In the event that an MCO pressure relief valve fails to open, the probability is 1 in 100 that the MCO would experience

  16. Childhood conditions and current physical performance among non-institutionalized individuals aged 50+ in Israel.

    Science.gov (United States)

    Weinstein, Galit

    2016-12-01

    Adverse socioeconomic conditions in childhood have been previously linked with high risk of various health conditions. However, the association with future physical function has been less studied. Hand grip strength and chair-rising time are objective measures of physical capability indicating current and future health outcomes. The aim of this study was to test the hypothesis that perceived socio-economic status in childhood is related to current measures of physical function, among Israeli participants of the Survey of Health, Ageing and Retirement in Europe project. The study included 2300 participants aged 50 years or older (mean age 68 ± 10; 56 % women). Generalized linear regression models were used to examine the associations of childhood wealth and number of books in residence with grip strength and time to complete five rises from a chair. Logistic regression models were used to assess the relationships between the early life conditions and the ability to perform the physical tests. Adjustment was made for current income or household wealth, and for demographic, anthropometric, health, and life-style measures. Being wealthy and having a large number of books at home in childhood was associated with a stronger hand grip and a better chair-rise test performance. These associations were more robust in women compared to men, and persisted after adjustment for potential covariates. In addition, childhood wealth and number of books were associated with lower risk of being unable to perform the tests. Thus, early-life programming may contribute to physical function indicators in mid- and late-life.

  17. The estimated lifetime probability of acquiring human papillomavirus in the United States.

    Science.gov (United States)

    Chesson, Harrell W; Dunne, Eileen F; Hariri, Susan; Markowitz, Lauri E

    2014-11-01

    Estimates of the lifetime probability of acquiring human papillomavirus (HPV) can help to quantify HPV incidence, illustrate how common HPV infection is, and highlight the importance of HPV vaccination. We developed a simple model, based primarily on the distribution of lifetime numbers of sex partners across the population and the per-partnership probability of acquiring HPV, to estimate the lifetime probability of acquiring HPV in the United States in the time frame before HPV vaccine availability. We estimated the average lifetime probability of acquiring HPV among those with at least 1 opposite sex partner to be 84.6% (range, 53.6%-95.0%) for women and 91.3% (range, 69.5%-97.7%) for men. Under base case assumptions, more than 80% of women and men acquire HPV by age 45 years. Our results are consistent with estimates in the existing literature suggesting a high lifetime probability of HPV acquisition and are supported by cohort studies showing high cumulative HPV incidence over a relatively short period, such as 3 to 5 years.

  18. Introduction to probability

    CERN Document Server

    Freund, John E

    1993-01-01

    Thorough, lucid coverage of permutations and factorials, probabilities and odds, frequency interpretation, mathematical expectation, decision making, postulates of probability, rule of elimination, binomial distribution, geometric distribution, standard deviation, law of large numbers, and much more. Exercises with some solutions. Summary. Bibliography. Includes 42 black-and-white illustrations. 1973 edition.

  19. The organizing-pedagogical conditions of students‟ training for the leadership of preschool age children‟ manual work

    Directory of Open Access Journals (Sweden)

    Halyna Boryn

    2017-02-01

    Full Text Available The necessity of security the joint organizing-pedagogical conditions in the educationalprocess of higher educational institution, which would contribute to successful forming offuture educators’ readiness to leadership of preschool age children’ manual work through themastering of standard subjects’ content are substantiated in the article.Key words: professional training, preschool age children, organizing-pedagogicalconditions, manual work.

  20. Pipe failure probability - the Thomas paper revisited

    International Nuclear Information System (INIS)

    Lydell, B.O.Y.

    2000-01-01

    Almost twenty years ago, in Volume 2 of Reliability Engineering (the predecessor of Reliability Engineering and System Safety), a paper by H. M. Thomas of Rolls Royce and Associates Ltd. presented a generalized approach to the estimation of piping and vessel failure probability. The 'Thomas-approach' used insights from actual failure statistics to calculate the probability of leakage and conditional probability of rupture given leakage. It was intended for practitioners without access to data on the service experience with piping and piping system components. This article revisits the Thomas paper by drawing on insights from development of a new database on piping failures in commercial nuclear power plants worldwide (SKI-PIPE). Partially sponsored by the Swedish Nuclear Power Inspectorate (SKI), the R and D leading up to this note was performed during 1994-1999. Motivated by data requirements of reliability analysis and probabilistic safety assessment (PSA), the new database supports statistical analysis of piping failure data. Against the background of this database development program, the article reviews the applicability of the 'Thomas approach' in applied risk and reliability analysis. It addresses the question whether a new and expanded database on the service experience with piping systems would alter the original piping reliability correlation as suggested by H. M. Thomas

  1. Demand-specific work ability, poor health and working conditions in middle-aged full-time employees

    DEFF Research Database (Denmark)

    Nabe-Nielsen, Kirsten; Thielen, Karsten; Nygaard, Else

    2014-01-01

    -sectional questionnaire data from 3381 full-time employees responding to questions about vocational education, job demands and social support (working conditions), musculoskeletal pain (MSP) and major depression (MD) (poor health) and seven questions about difficulty managing different job demands (reduced demand......We investigated the prevalence of reduced demand-specific work ability, its association with age, gender, education, poor health, and working conditions, and the interaction between poor health and working conditions regarding reduced demand-specific work ability. We used cross...... was associated with six measures of reduced demand-specific work ability. We found no interaction between working conditions and poor health regarding reduced demand-specific work ability....

  2. Parental Post-traumatic Stress Disorder Symptoms Are Related to Successful Aging in Offspring of Holocaust Survivors

    Science.gov (United States)

    Shrira, Amit; Ayalon, Liat; Bensimon, Moshe; Bodner, Ehud; Rosenbloom, Tova; Yadid, Gal

    2017-01-01

    A fascinating, yet underexplored, question is whether traumatic events experienced by previous generations affect the aging process of subsequent generations. This question is especially relevant for offspring of Holocaust survivors (OHS), who begin to face the aging process. Some preliminary findings point to greater physical dysfunction among middle-aged OHS, yet the mechanisms behind this dysfunction need further clarification. Therefore, the current studies assess aging OHS using the broad-scoped conceptualization of successful aging, while examining whether offspring successful aging relates to parental post-traumatic stress disorder (PTSD) symptoms and offspring’s secondary traumatization symptoms. In Study 1, 101 adult offspring (mean age = 62.31) completed measures of parental PTSD, secondary traumatization, as well as successful aging indices – objective (medical conditions, disability and somatic symptoms) and subjective (perceptions of one’s aging). Relative to comparisons and OHS who reported that none of their parents suffered from probable PTSD, OHS who reported that their parents suffered from probable PTSD had lower scores in objective and subjective measures of successful aging. Mediation analyses showed that higher level of secondary traumatization mediated the relationship between parental PTSD and less successful aging in the offspring. Study 2 included 154 dyads of parents (mean age = 81.86) and their adult offspring (mean age = 54.48). Parents reported PTSD symptoms and offspring reported secondary traumatization and completed measures of objective successful aging. Relative to comparisons, OHS whose parent had probable PTSD have aged less successfully. Once again, offspring secondary traumatization mediated the effect. The findings suggest that parental post-traumatic reactions assessed both by offspring (Study 1) and by parents themselves (Study 2) take part in shaping the aging of the subsequent generation via reactions of secondary

  3. Parental Post-traumatic Stress Disorder Symptoms Are Related to Successful Aging in Offspring of Holocaust Survivors

    Directory of Open Access Journals (Sweden)

    Amit Shrira

    2017-06-01

    Full Text Available A fascinating, yet underexplored, question is whether traumatic events experienced by previous generations affect the aging process of subsequent generations. This question is especially relevant for offspring of Holocaust survivors (OHS, who begin to face the aging process. Some preliminary findings point to greater physical dysfunction among middle-aged OHS, yet the mechanisms behind this dysfunction need further clarification. Therefore, the current studies assess aging OHS using the broad-scoped conceptualization of successful aging, while examining whether offspring successful aging relates to parental post-traumatic stress disorder (PTSD symptoms and offspring’s secondary traumatization symptoms. In Study 1, 101 adult offspring (mean age = 62.31 completed measures of parental PTSD, secondary traumatization, as well as successful aging indices – objective (medical conditions, disability and somatic symptoms and subjective (perceptions of one’s aging. Relative to comparisons and OHS who reported that none of their parents suffered from probable PTSD, OHS who reported that their parents suffered from probable PTSD had lower scores in objective and subjective measures of successful aging. Mediation analyses showed that higher level of secondary traumatization mediated the relationship between parental PTSD and less successful aging in the offspring. Study 2 included 154 dyads of parents (mean age = 81.86 and their adult offspring (mean age = 54.48. Parents reported PTSD symptoms and offspring reported secondary traumatization and completed measures of objective successful aging. Relative to comparisons, OHS whose parent had probable PTSD have aged less successfully. Once again, offspring secondary traumatization mediated the effect. The findings suggest that parental post-traumatic reactions assessed both by offspring (Study 1 and by parents themselves (Study 2 take part in shaping the aging of the subsequent generation via reactions of

  4. Probably not future prediction using probability and statistical inference

    CERN Document Server

    Dworsky, Lawrence N

    2008-01-01

    An engaging, entertaining, and informative introduction to probability and prediction in our everyday lives Although Probably Not deals with probability and statistics, it is not heavily mathematical and is not filled with complex derivations, proofs, and theoretical problem sets. This book unveils the world of statistics through questions such as what is known based upon the information at hand and what can be expected to happen. While learning essential concepts including "the confidence factor" and "random walks," readers will be entertained and intrigued as they move from chapter to chapter. Moreover, the author provides a foundation of basic principles to guide decision making in almost all facets of life including playing games, developing winning business strategies, and managing personal finances. Much of the book is organized around easy-to-follow examples that address common, everyday issues such as: How travel time is affected by congestion, driving speed, and traffic lights Why different gambling ...

  5. Preventive maintenance optimization for a stochastically degrading system with a random initial age

    International Nuclear Information System (INIS)

    Sidibe, I.B.; Khatab, A.; Diallo, C.; Kassambara, A.

    2017-01-01

    This paper investigates the optimal age replacement policy for used systems, such as second-hand products, which start their second life-cycle in a more severe environment with an initial age that is uncertain. This uncertain age is modelled as a random variable following continuous probability distributions. A mathematical model is developed to minimize the total expected cost per unit of time for these systems on an infinite time horizon. Optimality and existence conditions for a unique optimal solution are derived and used in a numerical procedure to solve the problem. Numerical experiments are provided to demonstrate the added value and the impacts of the random initial age on the optimal replacement policy.

  6. Does foraging performance change with age in female little penguins (Eudyptula minor?

    Directory of Open Access Journals (Sweden)

    Ilka Zimmer

    Full Text Available Age-related changes in breeding performance are likely to be mediated through changes in parental foraging performance. We investigated the relationship of foraging performance with age in female little penguins at Phillip Island, Australia, during the guard phase of the 2005 breeding season. Foraging parameters were recorded with accelerometers for birds grouped into three age-classes: (1 young, (2 middle age and (3 old females. We found the diving behaviour of middle-aged birds differed from young and old birds. The dive duration of middle age females was shorter than that of young and old birds while their dive effort (measure for dive and post-dive duration relation was lower than that of young ones, suggesting middle-aged birds were in better physical condition than other ones. There was no difference in prey pursuit frequency or duration between age classes, but in the hunting tactic. Females pursued more prey around and after reaching the maximum depth of dives the more experienced they were (old > middle age > young, an energy saving hunting tactic by probably taking advantage of up-thrust momentum. We suggest middle age penguins forage better than young or old ones because good physical condition and foraging experience could act simultaneously.

  7. Computing exact bundle compliance control charts via probability generating functions.

    Science.gov (United States)

    Chen, Binchao; Matis, Timothy; Benneyan, James

    2016-06-01

    Compliance to evidenced-base practices, individually and in 'bundles', remains an important focus of healthcare quality improvement for many clinical conditions. The exact probability distribution of composite bundle compliance measures used to develop corresponding control charts and other statistical tests is based on a fairly large convolution whose direct calculation can be computationally prohibitive. Various series expansions and other approximation approaches have been proposed, each with computational and accuracy tradeoffs, especially in the tails. This same probability distribution also arises in other important healthcare applications, such as for risk-adjusted outcomes and bed demand prediction, with the same computational difficulties. As an alternative, we use probability generating functions to rapidly obtain exact results and illustrate the improved accuracy and detection over other methods. Numerical testing across a wide range of applications demonstrates the computational efficiency and accuracy of this approach.

  8. Risk Probabilities

    DEFF Research Database (Denmark)

    Rojas-Nandayapa, Leonardo

    Tail probabilities of sums of heavy-tailed random variables are of a major importance in various branches of Applied Probability, such as Risk Theory, Queueing Theory, Financial Management, and are subject to intense research nowadays. To understand their relevance one just needs to think...... analytic expression for the distribution function of a sum of random variables. The presence of heavy-tailed random variables complicates the problem even more. The objective of this dissertation is to provide better approximations by means of sharp asymptotic expressions and Monte Carlo estimators...

  9. Conditional survival in patients with chronic myeloid leukemia in chronic phase in the era of tyrosine kinase inhibitors.

    Science.gov (United States)

    Sasaki, Koji; Kantarjian, Hagop M; Jain, Preetesh; Jabbour, Elias J; Ravandi, Farhad; Konopleva, Marina; Borthakur, Gautam; Takahashi, Koichi; Pemmaraju, Naveen; Daver, Naval; Pierce, Sherry A; O'Brien, Susan M; Cortes, Jorge E

    2016-01-15

    Tyrosine kinase inhibitors (TKIs) significantly improve survival in patients with chronic myeloid leukemia in chronic phase (CML-CP). Conditional probability provides survival information in patients who have already survived for a specific period of time after treatment. Cumulative response and survival data from 6 consecutive frontline TKI clinical trials were analyzed. Conditional probability was calculated for failure-free survival (FFS), transformation-free survival (TFS), event-free survival (EFS), and overall survival (OS) according to depth of response within 1 year of the initiation of TKIs, including complete cytogenetic response, major molecular response, and molecular response with a 4-log or 4.5-log reduction. A total of 483 patients with a median follow-up of 99.4 months from the initiation of treatment with TKIs were analyzed. Conditional probabilities of FFS, TFS, EFS, and OS for 1 additional year for patients alive after 12 months of therapy ranged from 92.0% to 99.1%, 98.5% to 100%, 96.2% to 99.6%, and 96.8% to 99.7%, respectively. Conditional FFS for 1 additional year did not improve with a deeper response each year. Conditional probabilities of TFS, EFS, and OS for 1 additional year were maintained at >95% during the period. In the era of TKIs, patients with chronic myeloid leukemia in chronic phase who survived for a certain number of years maintained excellent clinical outcomes in each age group. Cancer 2016;122:238-248. © 2015 American Cancer Society. © 2015 American Cancer Society.

  10. Modeling the probability distribution of peak discharge for infiltrating hillslopes

    Science.gov (United States)

    Baiamonte, Giorgio; Singh, Vijay P.

    2017-07-01

    Hillslope response plays a fundamental role in the prediction of peak discharge at the basin outlet. The peak discharge for the critical duration of rainfall and its probability distribution are needed for designing urban infrastructure facilities. This study derives the probability distribution, denoted as GABS model, by coupling three models: (1) the Green-Ampt model for computing infiltration, (2) the kinematic wave model for computing discharge hydrograph from the hillslope, and (3) the intensity-duration-frequency (IDF) model for computing design rainfall intensity. The Hortonian mechanism for runoff generation is employed for computing the surface runoff hydrograph. Since the antecedent soil moisture condition (ASMC) significantly affects the rate of infiltration, its effect on the probability distribution of peak discharge is investigated. Application to a watershed in Sicily, Italy, shows that with the increase of probability, the expected effect of ASMC to increase the maximum discharge diminishes. Only for low values of probability, the critical duration of rainfall is influenced by ASMC, whereas its effect on the peak discharge seems to be less for any probability. For a set of parameters, the derived probability distribution of peak discharge seems to be fitted by the gamma distribution well. Finally, an application to a small watershed, with the aim to test the possibility to arrange in advance the rational runoff coefficient tables to be used for the rational method, and a comparison between peak discharges obtained by the GABS model with those measured in an experimental flume for a loamy-sand soil were carried out.

  11. Quantum processes: probability fluxes, transition probabilities in unit time and vacuum vibrations

    International Nuclear Information System (INIS)

    Oleinik, V.P.; Arepjev, Ju D.

    1989-01-01

    Transition probabilities in unit time and probability fluxes are compared in studying the elementary quantum processes -the decay of a bound state under the action of time-varying and constant electric fields. It is shown that the difference between these quantities may be considerable, and so the use of transition probabilities W instead of probability fluxes Π, in calculating the particle fluxes, may lead to serious errors. The quantity W represents the rate of change with time of the population of the energy levels relating partly to the real states and partly to the virtual ones, and it cannot be directly measured in experiment. The vacuum background is shown to be continuously distorted when a perturbation acts on a system. Because of this the viewpoint of an observer on the physical properties of real particles continuously varies with time. This fact is not taken into consideration in the conventional theory of quantum transitions based on using the notion of probability amplitude. As a result, the probability amplitudes lose their physical meaning. All the physical information on quantum dynamics of a system is contained in the mean values of physical quantities. The existence of considerable differences between the quantities W and Π permits one in principle to make a choice of the correct theory of quantum transitions on the basis of experimental data. (author)

  12. Early-life conditions and health at older ages: The mediating role of educational attainment, family and employment trajectories.

    Science.gov (United States)

    Arpino, Bruno; Gumà, Jordi; Julià, Albert

    2018-01-01

    We examine to what extent the effect of early-life conditions (health and socioeconomic status) on health in later life is mediated by educational attainment and life-course trajectories (fertility, partnership, employment). Using data from the Survey of Health, Ageing and Retirement in Europe (N = 12,034), we apply, separately by gender, multichannel sequence analysis and cluster analysis to obtain groups of similar family and employment histories. The KHB method is used to disentangle direct and indirect effects of early-life conditions on health. Early-life-conditions indirectly impact on health in later life as result of their influence on education and family and employment trajectories. For example, between 22% and 42% of the effect of low parental socio-economic status at childhood on the three considered health outcomes at older age is explained by educational attainment for women. Even higher percentages are found for men (35% - 57%). On the contrary, the positive effect of poor health at childhood on poor health at older ages is not significantly mediated by education and life-course trajectories. Education captures most of the mediating effect of parental socio-economic status. More specifically, between 66% and 75% of the indirect effect of low parental socio-economic status at childhood on the three considered health outcomes at older age is explained by educational attainment for women. Again, higher percentages are found for men (86% - 93%). Early-life conditions, especially socioeconomic status, influence family and employment trajectories indirectly through their impact on education. We also find a persistent direct impact of early-life conditions on health at older ages. Our findings demonstrate that early-life experiences influence education and life-course trajectories and health in later life, suggesting that public investments in children are expected to produce long lasting effects on people's lives throughout the different phases of their

  13. Optimum conditions for aging of stainless maraging steels

    International Nuclear Information System (INIS)

    Mironenko, P.A.; Krasnikova, S.I.; Drobot, A.V.

    1980-01-01

    Aging kinetics of two 0Kh11N10M2T type steels in which 3 % Mo (steel 1), and 3 % Mo and 11 % Co (steel 2) had been additionally introduced instead of titanium were investigated. Electron microscopy and X-ray methods were used. It was ascertained that the process of steel aging proceeded in 3 stages. Steel 2 was hardened more intensively during the aging, had a higher degree of hardness and strength after the aging, weakened more slowly if overaged than steel 1. The intermetallide hcp-phase Fe 2 Mo was the hardening phase on steels extended aging. Optimum combination of impact strength and strength was was achieved using two-stage aging: the first stage - maximum strength aging was achieved, the second stage - aging at minimum temperatures of two-phase α+γ region

  14. Betting on conditionals

    OpenAIRE

    Politzer , Guy; Over , David P; Baratgin , Jean

    2010-01-01

    A study is reported testing two hypotheses about a close parallel relation between indicative conditionals, if A then B, and conditional bets, I bet you that if A then B. The first is that both the indicative conditional and the conditional bet are related to the conditional probability, P(B|A). The second is that de Finetti's three-valued truth table has psychological reality for both types of conditional – true, false, or void for indicative conditionals and win, lose or void for conditiona...

  15. The Effects of Framing, Reflection, Probability, and Payoff on Risk Preference in Choice Tasks.

    Science.gov (United States)

    Kühberger; Schulte-Mecklenbeck; Perner

    1999-06-01

    A meta-analysis of Asian-disease-like studies is presented to identify the factors which determine risk preference. First the confoundings between probability levels, payoffs, and framing conditions are clarified in a task analysis. Then the role of framing, reflection, probability, type, and size of payoff is evaluated in a meta-analysis. It is shown that bidirectional framing effects exist for gains and for losses. Presenting outcomes as gains tends to induce risk aversion, while presenting outcomes as losses tends to induce risk seeking. Risk preference is also shown to depend on the size of the payoffs, on the probability levels, and on the type of good at stake (money/property vs human lives). In general, higher payoffs lead to increasing risk aversion. Higher probabilities lead to increasing risk aversion for gains and to increasing risk seeking for losses. These findings are confirmed by a subsequent empirical test. Shortcomings of existing formal theories, such as prospect theory, cumulative prospect theory, venture theory, and Markowitz's utility theory, are identified. It is shown that it is not probabilities or payoffs, but the framing condition, which explains most variance. These findings are interpreted as showing that no linear combination of formally relevant predictors is sufficient to capture the essence of the framing phenomenon. Copyright 1999 Academic Press.

  16. The Context Matters: Outcome Probability and Expectation Mismatch Modulate the Feedback Negativity When Self-Evaluation of Response Correctness Is Possible.

    Science.gov (United States)

    Leue, Anja; Cano Rodilla, Carmen; Beauducel, André

    2015-01-01

    Individuals typically evaluate whether their performance and the obtained feedback match. Previous research has shown that feedback negativity (FN) depends on outcome probability and feedback valence. It is, however, less clear to what extent previous effects of outcome probability on FN depend on self-evaluations of response correctness. Therefore, we investigated the effects of outcome probability on FN amplitude in a simple go/no-go task that allowed for the self-evaluation of response correctness. We also investigated effects of performance incompatibility and feedback valence. In a sample of N = 22 participants, outcome probability was manipulated by means of precues, feedback valence by means of monetary feedback, and performance incompatibility by means of feedback that induced a match versus mismatch with individuals' performance. We found that the 100% outcome probability condition induced a more negative FN following no-loss than the 50% outcome probability condition. The FN following loss was more negative in the 50% compared to the 100% outcome probability condition. Performance-incompatible loss resulted in a more negative FN than performance-compatible loss. Our results indicate that the self-evaluation of the correctness of responses should be taken into account when the effects of outcome probability and expectation mismatch on FN are investigated.

  17. Propensity, Probability, and Quantum Theory

    Science.gov (United States)

    Ballentine, Leslie E.

    2016-08-01

    Quantum mechanics and probability theory share one peculiarity. Both have well established mathematical formalisms, yet both are subject to controversy about the meaning and interpretation of their basic concepts. Since probability plays a fundamental role in QM, the conceptual problems of one theory can affect the other. We first classify the interpretations of probability into three major classes: (a) inferential probability, (b) ensemble probability, and (c) propensity. Class (a) is the basis of inductive logic; (b) deals with the frequencies of events in repeatable experiments; (c) describes a form of causality that is weaker than determinism. An important, but neglected, paper by P. Humphreys demonstrated that propensity must differ mathematically, as well as conceptually, from probability, but he did not develop a theory of propensity. Such a theory is developed in this paper. Propensity theory shares many, but not all, of the axioms of probability theory. As a consequence, propensity supports the Law of Large Numbers from probability theory, but does not support Bayes theorem. Although there are particular problems within QM to which any of the classes of probability may be applied, it is argued that the intrinsic quantum probabilities (calculated from a state vector or density matrix) are most naturally interpreted as quantum propensities. This does not alter the familiar statistical interpretation of QM. But the interpretation of quantum states as representing knowledge is untenable. Examples show that a density matrix fails to represent knowledge.

  18. Recruitment in a Colorado population of big brown bats: Breeding probabilities, litter size, and first-year survival

    Science.gov (United States)

    O'Shea, T.J.; Ellison, L.E.; Neubaum, D.J.; Neubaum, M.A.; Reynolds, C.A.; Bowen, R.A.

    2010-01-01

    We used markrecapture estimation techniques and radiography to test hypotheses about 3 important aspects of recruitment in big brown bats (Eptesicus fuscus) in Fort Collins, Colorado: adult breeding probabilities, litter size, and 1st-year survival of young. We marked 2,968 females with passive integrated transponder (PIT) tags at multiple sites during 2001-2005 and based our assessments on direct recaptures (breeding probabilities) and passive detection with automated PIT tag readers (1st-year survival). We interpreted our data in relation to hypotheses regarding demographic influences of bat age, roost, and effects of years with unusual environmental conditions: extreme drought (2002) and arrival of a West Nile virus epizootic (2003). Conditional breeding probabilities at 6 roosts sampled in 2002-2005 were estimated as 0.64 (95% confidence interval [95% CI] = 0.530.73) in 1-year-old females, but were consistently high (95% CI = 0.940.96) and did not vary by roost, year, or prior year breeding status in older adults. Mean litter size was 1.11 (95% CI = 1.051.17), based on examination of 112 pregnant females by radiography. Litter size was not higher in older or larger females and was similar to results of other studies in western North America despite wide variation in latitude. First-year survival was estimated as 0.67 (95% CI = 0.610.73) for weaned females at 5 maternity roosts over 5 consecutive years, was lower than adult survival (0.79; 95% CI = 0.770.81), and varied by roost. Based on model selection criteria, strong evidence exists for complex roost and year effects on 1st-year survival. First-year survival was lowest in bats born during the drought year. Juvenile females that did not return to roosts as 1-year-olds had lower body condition indices in late summer of their natal year than those known to survive. ?? 2009 American Society of Mammalogists.

  19. Delaying childbearing : Effect of age on fecundity and outcome of pregnancy

    NARCIS (Netherlands)

    Noord-Zaadstra, B.M. van; Looman, C.W.N.; Alsbach, H.; Habbema, J.D.F.; Velde, E.R. te; Karbaat, J.

    1991-01-01

    Objectives - To study the age of the start of the fall (critical age) in fecundity; the probability of a pregnancy leading to a healthy baby taking into account the age of the woman; and, combining these results, to determine the age dependent probability of getting a healthy baby. Design - Cohort

  20. Choice Probability Generating Functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel L; Bierlaire, Michel

    This paper considers discrete choice, with choice probabilities coming from maximization of preferences from a random utility field perturbed by additive location shifters (ARUM). Any ARUM can be characterized by a choice-probability generating function (CPGF) whose gradient gives the choice...... probabilities, and every CPGF is consistent with an ARUM. We relate CPGF to multivariate extreme value distributions, and review and extend methods for constructing CPGF for applications....

  1. Estimation of the probability of success in petroleum exploration

    Science.gov (United States)

    Davis, J.C.

    1977-01-01

    A probabilistic model for oil exploration can be developed by assessing the conditional relationship between perceived geologic variables and the subsequent discovery of petroleum. Such a model includes two probabilistic components, the first reflecting the association between a geologic condition (structural closure, for example) and the occurrence of oil, and the second reflecting the uncertainty associated with the estimation of geologic variables in areas of limited control. Estimates of the conditional relationship between geologic variables and subsequent production can be found by analyzing the exploration history of a "training area" judged to be geologically similar to the exploration area. The geologic variables are assessed over the training area using an historical subset of the available data, whose density corresponds to the present control density in the exploration area. The success or failure of wells drilled in the training area subsequent to the time corresponding to the historical subset provides empirical estimates of the probability of success conditional upon geology. Uncertainty in perception of geological conditions may be estimated from the distribution of errors made in geologic assessment using the historical subset of control wells. These errors may be expressed as a linear function of distance from available control. Alternatively, the uncertainty may be found by calculating the semivariogram of the geologic variables used in the analysis: the two procedures will yield approximately equivalent results. The empirical probability functions may then be transferred to the exploration area and used to estimate the likelihood of success of specific exploration plays. These estimates will reflect both the conditional relationship between the geological variables used to guide exploration and the uncertainty resulting from lack of control. The technique is illustrated with case histories from the mid-Continent area of the U.S.A. ?? 1977 Plenum

  2. Prediction and probability in sciences

    International Nuclear Information System (INIS)

    Klein, E.; Sacquin, Y.

    1998-01-01

    This book reports the 7 presentations made at the third meeting 'physics and fundamental questions' whose theme was probability and prediction. The concept of probability that was invented to apprehend random phenomena has become an important branch of mathematics and its application range spreads from radioactivity to species evolution via cosmology or the management of very weak risks. The notion of probability is the basis of quantum mechanics and then is bound to the very nature of matter. The 7 topics are: - radioactivity and probability, - statistical and quantum fluctuations, - quantum mechanics as a generalized probability theory, - probability and the irrational efficiency of mathematics, - can we foresee the future of the universe?, - chance, eventuality and necessity in biology, - how to manage weak risks? (A.C.)

  3. Informing Environmental Water Management Decisions: Using Conditional Probability Networks to Address the Information Needs of Planning and Implementation Cycles

    Science.gov (United States)

    Horne, Avril C.; Szemis, Joanna M.; Webb, J. Angus; Kaur, Simranjit; Stewardson, Michael J.; Bond, Nick; Nathan, Rory

    2018-03-01

    One important aspect of adaptive management is the clear and transparent documentation of hypotheses, together with the use of predictive models (complete with any assumptions) to test those hypotheses. Documentation of such models can improve the ability to learn from management decisions and supports dialog between stakeholders. A key challenge is how best to represent the existing scientific knowledge to support decision-making. Such challenges are currently emerging in the field of environmental water management in Australia, where managers are required to prioritize the delivery of environmental water on an annual basis, using a transparent and evidence-based decision framework. We argue that the development of models of ecological responses to environmental water use needs to support both the planning and implementation cycles of adaptive management. Here we demonstrate an approach based on the use of Conditional Probability Networks to translate existing ecological knowledge into quantitative models that include temporal dynamics to support adaptive environmental flow management. It equally extends to other applications where knowledge is incomplete, but decisions must still be made.

  4. Informing Environmental Water Management Decisions: Using Conditional Probability Networks to Address the Information Needs of Planning and Implementation Cycles.

    Science.gov (United States)

    Horne, Avril C; Szemis, Joanna M; Webb, J Angus; Kaur, Simranjit; Stewardson, Michael J; Bond, Nick; Nathan, Rory

    2018-03-01

    One important aspect of adaptive management is the clear and transparent documentation of hypotheses, together with the use of predictive models (complete with any assumptions) to test those hypotheses. Documentation of such models can improve the ability to learn from management decisions and supports dialog between stakeholders. A key challenge is how best to represent the existing scientific knowledge to support decision-making. Such challenges are currently emerging in the field of environmental water management in Australia, where managers are required to prioritize the delivery of environmental water on an annual basis, using a transparent and evidence-based decision framework. We argue that the development of models of ecological responses to environmental water use needs to support both the planning and implementation cycles of adaptive management. Here we demonstrate an approach based on the use of Conditional Probability Networks to translate existing ecological knowledge into quantitative models that include temporal dynamics to support adaptive environmental flow management. It equally extends to other applications where knowledge is incomplete, but decisions must still be made.

  5. Predictive probability methods for interim monitoring in clinical trials with longitudinal outcomes.

    Science.gov (United States)

    Zhou, Ming; Tang, Qi; Lang, Lixin; Xing, Jun; Tatsuoka, Kay

    2018-04-17

    In clinical research and development, interim monitoring is critical for better decision-making and minimizing the risk of exposing patients to possible ineffective therapies. For interim futility or efficacy monitoring, predictive probability methods are widely adopted in practice. Those methods have been well studied for univariate variables. However, for longitudinal studies, predictive probability methods using univariate information from only completers may not be most efficient, and data from on-going subjects can be utilized to improve efficiency. On the other hand, leveraging information from on-going subjects could allow an interim analysis to be potentially conducted once a sufficient number of subjects reach an earlier time point. For longitudinal outcomes, we derive closed-form formulas for predictive probabilities, including Bayesian predictive probability, predictive power, and conditional power and also give closed-form solutions for predictive probability of success in a future trial and the predictive probability of success of the best dose. When predictive probabilities are used for interim monitoring, we study their distributions and discuss their analytical cutoff values or stopping boundaries that have desired operating characteristics. We show that predictive probabilities utilizing all longitudinal information are more efficient for interim monitoring than that using information from completers only. To illustrate their practical application for longitudinal data, we analyze 2 real data examples from clinical trials. Copyright © 2018 John Wiley & Sons, Ltd.

  6. Predicting longitudinal trajectories of health probabilities with random-effects multinomial logit regression.

    Science.gov (United States)

    Liu, Xian; Engel, Charles C

    2012-12-20

    Researchers often encounter longitudinal health data characterized with three or more ordinal or nominal categories. Random-effects multinomial logit models are generally applied to account for potential lack of independence inherent in such clustered data. When parameter estimates are used to describe longitudinal processes, however, random effects, both between and within individuals, need to be retransformed for correctly predicting outcome probabilities. This study attempts to go beyond existing work by developing a retransformation method that derives longitudinal growth trajectories of unbiased health probabilities. We estimated variances of the predicted probabilities by using the delta method. Additionally, we transformed the covariates' regression coefficients on the multinomial logit function, not substantively meaningful, to the conditional effects on the predicted probabilities. The empirical illustration uses the longitudinal data from the Asset and Health Dynamics among the Oldest Old. Our analysis compared three sets of the predicted probabilities of three health states at six time points, obtained from, respectively, the retransformation method, the best linear unbiased prediction, and the fixed-effects approach. The results demonstrate that neglect of retransforming random errors in the random-effects multinomial logit model results in severely biased longitudinal trajectories of health probabilities as well as overestimated effects of covariates on the probabilities. Copyright © 2012 John Wiley & Sons, Ltd.

  7. Failure probability assessment of wall-thinned nuclear pipes using probabilistic fracture mechanics

    International Nuclear Information System (INIS)

    Lee, Sang-Min; Chang, Yoon-Suk; Choi, Jae-Boong; Kim, Young-Jin

    2006-01-01

    The integrity of nuclear piping system has to be maintained during operation. In order to maintain the integrity, reliable assessment procedures including fracture mechanics analysis, etc., are required. Up to now, this has been performed using conventional deterministic approaches even though there are many uncertainties to hinder a rational evaluation. In this respect, probabilistic approaches are considered as an appropriate method for piping system evaluation. The objectives of this paper are to estimate the failure probabilities of wall-thinned pipes in nuclear secondary systems and to propose limited operating conditions under different types of loadings. To do this, a probabilistic assessment program using reliability index and simulation techniques was developed and applied to evaluate failure probabilities of wall-thinned pipes subjected to internal pressure, bending moment and combined loading of them. The sensitivity analysis results as well as prototypal integrity assessment results showed a promising applicability of the probabilistic assessment program, necessity of practical evaluation reflecting combined loading condition and operation considering limited condition

  8. Quantum operations, state transformations and probabilities

    International Nuclear Information System (INIS)

    Chefles, Anthony

    2002-01-01

    In quantum operations, probabilities characterize both the degree of the success of a state transformation and, as density operator eigenvalues, the degree of mixedness of the final state. We give a unified treatment of pure→pure state transformations, covering both probabilistic and deterministic cases. We then discuss the role of majorization in describing the dynamics of mixing in quantum operations. The conditions for mixing enhancement for all initial states are derived. We show that mixing is monotonically decreasing for deterministic pure→pure transformations, and discuss the relationship between these transformations and deterministic local operations with classical communication entanglement transformations

  9. Probability theory versus simulation of petroleum potential in play analysis

    Science.gov (United States)

    Crovelli, R.A.

    1987-01-01

    An analytic probabilistic methodology for resource appraisal of undiscovered oil and gas resources in play analysis is presented. This play-analysis methodology is a geostochastic system for petroleum resource appraisal in explored as well as frontier areas. An objective was to replace an existing Monte Carlo simulation method in order to increase the efficiency of the appraisal process. Underlying the two methods is a single geologic model which considers both the uncertainty of the presence of the assessed hydrocarbon and its amount if present. The results of the model are resource estimates of crude oil, nonassociated gas, dissolved gas, and gas for a geologic play in terms of probability distributions. The analytic method is based upon conditional probability theory and a closed form solution of all means and standard deviations, along with the probabilities of occurrence. ?? 1987 J.C. Baltzer A.G., Scientific Publishing Company.

  10. DORIAN, Bayes Method Plant Age Risk Analysis

    International Nuclear Information System (INIS)

    Atwood, C.L.

    2002-01-01

    1 - Description of program or function: DORIAN is an integrated package for performing Bayesian aging analysis of reliability data; e.g. for identifying trends in component failure rates and/or outage durations as a function of time. The user must specify several alternative hypothesized 'aging models' (i.e., possible trends) along prior probabilities indicating the subject probability that each trend is actually the correct one. DORIAN then uses component failure and/or repair data over time to update these prior probabilities and develop a posterior probability for each aging model, representing the probability that each model is the correct one in light of the observed data rather than a priori. Mean, median, and 5. and 95. percentile trends are also compiled from the posterior probabilities. 2 - Method of solution: DORIAN carries out a Bayesian analysis of failure data and a prior distribution on a time-dependent failure rate to obtain a posterior distribution on the failure rate. The form of the time-dependent failure rate is arbitrary, because DORIAN approximates the form by a step-function, constant within specified time intervals. Similarly, the parameters may have any prior distribution, because DORIAN uses a discrete distribution to approximate this. Likewise, the database file produced by DORIAN approximates the entire range of possible failure rates or outage durations developed by means of a discrete probability distribution containing no more than 20 distinct values with their probabilities. 3 - Restrictions on the complexity of the problem: Prior distribution is discrete with up to 25 values. Up to 60 times are accommodated in the discrete time history

  11. The quantum probability calculus

    International Nuclear Information System (INIS)

    Jauch, J.M.

    1976-01-01

    The Wigner anomaly (1932) for the joint distribution of noncompatible observables is an indication that the classical probability calculus is not applicable for quantum probabilities. It should, therefore, be replaced by another, more general calculus, which is specifically adapted to quantal systems. In this article this calculus is exhibited and its mathematical axioms and the definitions of the basic concepts such as probability field, random variable, and expectation values are given. (B.R.H)

  12. Disability Rating, Age at Death, and Cause of Death in U.S. Veterans with Service-Connected Conditions.

    Science.gov (United States)

    Maynard, Charles; Trivedi, Ranak; Nelson, Karin; Fihn, Stephan D

    2018-03-26

    The association between disability and cause of death in Veterans with service-connected disabilities has not been studied. The objective of this study was to compare age at death, military service and disability characteristics, including disability rating, and cause of death by year of birth. We also examined cause of death for specific service-connected conditions. This study used information from the VETSNET file, which is a snapshot of selected items from the Veterans Benefits Administration corporate database. We also used the National Death Index (NDI) for Veterans which is part of the VA Suicide Data Repository. In VETSNET, there were 758,324 Veterans who had a service-connected condition and died between the years 2004 and 2014. Using the scrambled social security number to link the two files resulted in 605,493 (80%) deceased Veterans. Age at death, sex, and underlying cause of death were obtained from the NDI for Veterans and military service characteristics and types of disability were acquired from VETSNET. We constructed age categories corresponding to period of service; birth years 1938 and earlier corresponded to Korea and World War II ("oldest"), birth years 1939-1957 to the Vietnam era ("middle"), and birth years 1958 and later to post Vietnam, Gulf War, and the more recent conflicts in Iraq and Afghanistan ("youngest"). Sixty-two percent were in the oldest age category, 34% in the middle group, and 4% in the youngest one. The overall age at death was 75 ± 13 yr. Only 1.6% of decedents were women; among women 25% were in the youngest age group, while among men only 4% were in the youngest group. Most decedents were enlisted personnel, and 60% served in the U.S. Army. Nearly 61% had a disability rating of >50% and for the middle age group 54% had a disability rating of 100%. The most common service-connected conditions were tinnitus, hearing loss, and post-traumatic stress disorder (PTSD). In the oldest group, nearly half of deaths were due to

  13. Computing under-ice discharge: A proof-of-concept using hydroacoustics and the Probability Concept

    Science.gov (United States)

    Fulton, John W.; Henneberg, Mark F.; Mills, Taylor J.; Kohn, Michael S.; Epstein, Brian; Hittle, Elizabeth A.; Damschen, William C.; Laveau, Christopher D.; Lambrecht, Jason M.; Farmer, William H.

    2018-01-01

    Under-ice discharge is estimated using open-water reference hydrographs; however, the ratings for ice-affected sites are generally qualified as poor. The U.S. Geological Survey (USGS), in collaboration with the Colorado Water Conservation Board, conducted a proof-of-concept to develop an alternative method for computing under-ice discharge using hydroacoustics and the Probability Concept.The study site was located south of Minturn, Colorado (CO), USA, and was selected because of (1) its proximity to the existing USGS streamgage 09064600 Eagle River near Minturn, CO, and (2) its ease-of-access to verify discharge using a variety of conventional methods. From late September 2014 to early March 2015, hydraulic conditions varied from open water to under ice. These temporal changes led to variations in water depth and velocity. Hydroacoustics (tethered and uplooking acoustic Doppler current profilers and acoustic Doppler velocimeters) were deployed to measure the vertical-velocity profile at a singularly important vertical of the channel-cross section. Because the velocity profile was non-standard and cannot be characterized using a Power Law or Log Law, velocity data were analyzed using the Probability Concept, which is a probabilistic formulation of the velocity distribution. The Probability Concept-derived discharge was compared to conventional methods including stage-discharge and index-velocity ratings and concurrent field measurements; each is complicated by the dynamics of ice formation, pressure influences on stage measurements, and variations in cross-sectional area due to ice formation.No particular discharge method was assigned as truth. Rather one statistical metric (Kolmogorov-Smirnov; KS), agreement plots, and concurrent measurements provided a measure of comparability between various methods. Regardless of the method employed, comparisons between each method revealed encouraging results depending on the flow conditions and the absence or presence of ice

  14. Design limits for HT9 cladding using stress-induced aging data

    International Nuclear Information System (INIS)

    Fox, G.L.

    1986-04-01

    Stress-temperature design guidelines are developed for the ferritic/martensitic cladding material HT9. High temperature operation for HT9 may cause microstructural changes/aging which softens the structure and causes increased creep rates. Higher creep strains means cladding breech becomes more probable before the end of the expected pin lifetime. Tertiary creep is considered an indication of microstructural changes and is to be avoided in fuel pin operation. The creep rate correlation, which includes tertiary creep, is examined for information on stress-temperature relationships which promote aging. This approach leads to design limits for HT9 which are compared with expected hot channel conditions for fuel pins in the Core Demonstration Experiment (CDE) planned for FFTF. The results show aging should not be significant for CDE

  15. Correlations between channel probabilities in collisional dissociation of D3+

    International Nuclear Information System (INIS)

    Abraham, S.; Nir, D.; Rosner, B.

    1984-01-01

    Measurements of the dissociation of D 3 + ions at 300--600 keV under single- and multiple-collision conditions in Ar- and H 2 -gas targets have been performed. A complete separation of all dissociation channels was achieved, including the neutral channels, which were resolved using a fine-mesh technique. Data analysis in the multiple-collision regime confirms the validity of the rate equations governing the charge exchange processes. In the single-collision region the analysis yields constant relations between channel probabilities. Data rearrangement shows probability factorization and suggests that collisional dissociation is a two-stage process, a fast electron exchange followed by rearrangement and branching to the exit channels

  16. Stochastic simulations of normal aging and Werner's syndrome.

    KAUST Repository

    Qi, Qi

    2014-04-26

    Human cells typically consist of 23 pairs of chromosomes. Telomeres are repetitive sequences of DNA located at the ends of chromosomes. During cell replication, a number of basepairs are lost from the end of the chromosome and this shortening restricts the number of divisions that a cell can complete before it becomes senescent, or non-replicative. In this paper, we use Monte Carlo simulations to form a stochastic model of telomere shortening to investigate how telomere shortening affects normal aging. Using this model, we study various hypotheses for the way in which shortening occurs by comparing their impact on aging at the chromosome and cell levels. We consider different types of length-dependent loss and replication probabilities to describe these processes. After analyzing a simple model for a population of independent chromosomes, we simulate a population of cells in which each cell has 46 chromosomes and the shortest telomere governs the replicative potential of the cell. We generalize these simulations to Werner\\'s syndrome, a condition in which large sections of DNA are removed during cell division and, amongst other conditions, results in rapid aging. Since the mechanisms governing the loss of additional basepairs are not known, we use our model to simulate a variety of possible forms for the rate at which additional telomeres are lost per replication and several expressions for how the probability of cell division depends on telomere length. As well as the evolution of the mean telomere length, we consider the standard deviation and the shape of the distribution. We compare our results with a variety of data from the literature, covering both experimental data and previous models. We find good agreement for the evolution of telomere length when plotted against population doubling.

  17. Failure probability analysis on mercury target vessel

    International Nuclear Information System (INIS)

    Ishikura, Syuichi; Futakawa, Masatoshi; Kogawa, Hiroyuki; Sato, Hiroshi; Haga, Katsuhiro; Ikeda, Yujiro

    2005-03-01

    Failure probability analysis was carried out to estimate the lifetime of the mercury target which will be installed into the JSNS (Japan spallation neutron source) in J-PARC (Japan Proton Accelerator Research Complex). The lifetime was estimated as taking loading condition and materials degradation into account. Considered loads imposed on the target vessel were the static stresses due to thermal expansion and static pre-pressure on He-gas and mercury and the dynamic stresses due to the thermally shocked pressure waves generated repeatedly at 25 Hz. Materials used in target vessel will be degraded by the fatigue, neutron and proton irradiation, mercury immersion and pitting damages, etc. The imposed stresses were evaluated through static and dynamic structural analyses. The material-degradations were deduced based on published experimental data. As a result, it was quantitatively confirmed that the failure probability for the lifetime expected in the design is very much lower, 10 -11 in the safety hull, meaning that it will be hardly failed during the design lifetime. On the other hand, the beam window of mercury vessel suffered with high-pressure waves exhibits the failure probability of 12%. It was concluded, therefore, that the leaked mercury from the failed area at the beam window is adequately kept in the space between the safety hull and the mercury vessel by using mercury-leakage sensors. (author)

  18. Excluding joint probabilities from quantum theory

    Science.gov (United States)

    Allahverdyan, Armen E.; Danageozian, Arshag

    2018-03-01

    Quantum theory does not provide a unique definition for the joint probability of two noncommuting observables, which is the next important question after the Born's probability for a single observable. Instead, various definitions were suggested, e.g., via quasiprobabilities or via hidden-variable theories. After reviewing open issues of the joint probability, we relate it to quantum imprecise probabilities, which are noncontextual and are consistent with all constraints expected from a quantum probability. We study two noncommuting observables in a two-dimensional Hilbert space and show that there is no precise joint probability that applies for any quantum state and is consistent with imprecise probabilities. This contrasts with theorems by Bell and Kochen-Specker that exclude joint probabilities for more than two noncommuting observables, in Hilbert space with dimension larger than two. If measurement contexts are included into the definition, joint probabilities are not excluded anymore, but they are still constrained by imprecise probabilities.

  19. The pleasures of probability

    CERN Document Server

    Isaac, Richard

    1995-01-01

    The ideas of probability are all around us. Lotteries, casino gambling, the al­ most non-stop polling which seems to mold public policy more and more­ these are a few of the areas where principles of probability impinge in a direct way on the lives and fortunes of the general public. At a more re­ moved level there is modern science which uses probability and its offshoots like statistics and the theory of random processes to build mathematical descriptions of the real world. In fact, twentieth-century physics, in embrac­ ing quantum mechanics, has a world view that is at its core probabilistic in nature, contrary to the deterministic one of classical physics. In addition to all this muscular evidence of the importance of probability ideas it should also be said that probability can be lots of fun. It is a subject where you can start thinking about amusing, interesting, and often difficult problems with very little mathematical background. In this book, I wanted to introduce a reader with at least a fairl...

  20. Probable Inference and Quantum Mechanics

    International Nuclear Information System (INIS)

    Grandy, W. T. Jr.

    2009-01-01

    In its current very successful interpretation the quantum theory is fundamentally statistical in nature. Although commonly viewed as a probability amplitude whose (complex) square is a probability, the wavefunction or state vector continues to defy consensus as to its exact meaning, primarily because it is not a physical observable. Rather than approach this problem directly, it is suggested that it is first necessary to clarify the precise role of probability theory in quantum mechanics, either as applied to, or as an intrinsic part of the quantum theory. When all is said and done the unsurprising conclusion is that quantum mechanics does not constitute a logic and probability unto itself, but adheres to the long-established rules of classical probability theory while providing a means within itself for calculating the relevant probabilities. In addition, the wavefunction is seen to be a description of the quantum state assigned by an observer based on definite information, such that the same state must be assigned by any other observer based on the same information, in much the same way that probabilities are assigned.

  1. Exact calculation of loop formation probability identifies folding motifs in RNA secondary structures

    Science.gov (United States)

    Sloma, Michael F.; Mathews, David H.

    2016-01-01

    RNA secondary structure prediction is widely used to analyze RNA sequences. In an RNA partition function calculation, free energy nearest neighbor parameters are used in a dynamic programming algorithm to estimate statistical properties of the secondary structure ensemble. Previously, partition functions have largely been used to estimate the probability that a given pair of nucleotides form a base pair, the conditional stacking probability, the accessibility to binding of a continuous stretch of nucleotides, or a representative sample of RNA structures. Here it is demonstrated that an RNA partition function can also be used to calculate the exact probability of formation of hairpin loops, internal loops, bulge loops, or multibranch loops at a given position. This calculation can also be used to estimate the probability of formation of specific helices. Benchmarking on a set of RNA sequences with known secondary structures indicated that loops that were calculated to be more probable were more likely to be present in the known structure than less probable loops. Furthermore, highly probable loops are more likely to be in the known structure than the set of loops predicted in the lowest free energy structures. PMID:27852924

  2. Emptiness formation probability of XX-chain in diffusion process

    International Nuclear Information System (INIS)

    Ogata, Yoshiko

    2004-01-01

    We study the distribution of emptiness formation probability of XX-model in the diffusion process. There exits a Gaussian decay as well as an exponential decay. The Gaussian decay is caused by the existence of zero point in the Fermi distribution function. The correlation length for each point of scaling factor varies up to the initial condition, monotonically or non-monotonically

  3. Does probability of occurrence relate to population dynamics?

    Science.gov (United States)

    Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H.; Georges, Damien; Dullinger, Stefan; Eckhart, Vincent M.; Edwards, Thomas C.; Gravel, Dominique; Kunstler, Georges; Merow, Cory; Moore, Kara; Piedallu, Christian; Vissault, Steve; Zimmermann, Niklaus E.; Zurell, Damaris; Schurr, Frank M.

    2014-01-01

    Hutchinson defined species' realized niche as the set of environmental conditions in which populations can persist in the presence of competitors. In terms of demography, the realized niche corresponds to the environments where the intrinsic growth rate (r) of populations is positive. Observed species occurrences should reflect the realized niche when additional processes like dispersal and local extinction lags do not have overwhelming effects. Despite the foundational nature of these ideas, quantitative assessments of the relationship between range-wide demographic performance and occurrence probability have not been made. This assessment is needed both to improve our conceptual understanding of species' niches and ranges and to develop reliable mechanistic models of species geographic distributions that incorporate demography and species interactions.The objective of this study is to analyse how demographic parameters (intrinsic growth rate r and carrying capacity K ) and population density (N ) relate to occurrence probability (Pocc ). We hypothesized that these relationships vary with species' competitive ability. Demographic parameters, density, and occurrence probability were estimated for 108 tree species from four temperate forest inventory surveys (Québec, western USA, France and Switzerland). We used published information of shade tolerance as indicators of light competition strategy, assuming that high tolerance denotes high competitive capacity in stable forest environments.Interestingly, relationships between demographic parameters and occurrence probability did not vary substantially across degrees of shade tolerance and regions. Although they were influenced by the uncertainty in the estimation of the demographic parameters, we found that r was generally negatively correlated with Pocc, while N, and for most regions K, was generally positively correlated with Pocc. Thus, in temperate forest trees the regions of highest occurrence

  4. Ensuring living condition for ageing population by public–private partnership (PPP

    Directory of Open Access Journals (Sweden)

    Konjar Miha

    2018-01-01

    Full Text Available Lack of financial resources has become one of the main issues in fulfilling social and physical needs in urban development. The declining levels of public resources make the collaboration between public and private investors necessary. When facing the challenges of ageing population, shared investment may contribute to the appropriate development of sheltered housing to meet the goals of spatial planning as well as certain standards at the level of urban design. By ensuring appropriate living conditions for all generations such urban PPP projects may contribute to the fulfilment of the public interest. The paper presents practice of PPP implementation in Ljubljana, Slovenia, where local authority with the collaboration of private partners ensured more than 400 sheltered apartments in the last years. Examples show the extension of the idea from the 70s onwards in finding new models of housing for the aging population. The development of new models can be a good example of strengthening the cooperation between public and private partners in the field of urban development practice.

  5. Ensuring living condition for ageing population by public-private partnership (PPP)

    Science.gov (United States)

    Konjar, Miha; Nikšič, Matej; Grom, Janez Peter; Mujkić, Sabina; Fikfak, Alenka

    2018-03-01

    Lack of financial resources has become one of the main issues in fulfilling social and physical needs in urban development. The declining levels of public resources make the collaboration between public and private investors necessary. When facing the challenges of ageing population, shared investment may contribute to the appropriate development of sheltered housing to meet the goals of spatial planning as well as certain standards at the level of urban design. By ensuring appropriate living conditions for all generations such urban PPP projects may contribute to the fulfilment of the public interest. The paper presents practice of PPP implementation in Ljubljana, Slovenia, where local authority with the collaboration of private partners ensured more than 400 sheltered apartments in the last years. Examples show the extension of the idea from the 70s onwards in finding new models of housing for the aging population. The development of new models can be a good example of strengthening the cooperation between public and private partners in the field of urban development practice.

  6. Psychophysics of the probability weighting function

    Science.gov (United States)

    Takahashi, Taiki

    2011-03-01

    A probability weighting function w(p) for an objective probability p in decision under risk plays a pivotal role in Kahneman-Tversky prospect theory. Although recent studies in econophysics and neuroeconomics widely utilized probability weighting functions, psychophysical foundations of the probability weighting functions have been unknown. Notably, a behavioral economist Prelec (1998) [4] axiomatically derived the probability weighting function w(p)=exp(-() (01e)=1e,w(1)=1), which has extensively been studied in behavioral neuroeconomics. The present study utilizes psychophysical theory to derive Prelec's probability weighting function from psychophysical laws of perceived waiting time in probabilistic choices. Also, the relations between the parameters in the probability weighting function and the probability discounting function in behavioral psychology are derived. Future directions in the application of the psychophysical theory of the probability weighting function in econophysics and neuroeconomics are discussed.

  7. Probability concepts in quality risk management.

    Science.gov (United States)

    Claycamp, H Gregg

    2012-01-01

    Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although risk is generally a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management tools are relatively silent on the meaning and uses of "probability." The probability concept is typically applied by risk managers as a combination of frequency-based calculation and a "degree of belief" meaning of probability. Probability as a concept that is crucial for understanding and managing risk is discussed through examples from the most general, scenario-defining and ranking tools that use probability implicitly to more specific probabilistic tools in risk management. A rich history of probability in risk management applied to other fields suggests that high-quality risk management decisions benefit from the implementation of more thoughtful probability concepts in both risk modeling and risk management. Essentially any concept of risk is built on fundamental concepts of chance, likelihood, or probability. Although "risk" generally describes a probability of loss of something of value, given that a risk-generating event will occur or has occurred, it is ironic that the quality risk management literature and guidelines on quality risk management methodologies and respective tools focus on managing severity but are relatively silent on the in-depth meaning and uses of "probability." Pharmaceutical manufacturers are expanding their use of quality risk management to identify and manage risks to the patient that might occur in phases of the pharmaceutical life cycle from drug development to manufacture, marketing to product discontinuation. A probability concept is typically applied by risk managers as a combination of data-based measures of probability and a subjective "degree of belief" meaning of probability. Probability as

  8. The effect of floods on anemia among reproductive age women in Afghanistan.

    Science.gov (United States)

    Oskorouchi, Hamid Reza; Nie, Peng; Sousa-Poza, Alfonso

    2018-01-01

    This study uses biomarker information from the 2013 National Nutrition Survey Afghanistan and satellite precipitation driven modeling results from the Global Flood Monitoring System to analyze how floods affect the probability of anemia in Afghan women of reproductive age (15-49). In addition to establishing a causal relation between the two by exploiting the quasi-random variation of floods in different districts and periods, the analysis demonstrates that floods have a significant positive effect on the probability of anemia through two possible transmission mechanisms. The first is a significant effect on inflammation, probably related to water borne diseases carried by unsafe drinking water, and the second is a significant negative effect on retinol concentrations. Because the effect of floods on anemia remains significant even after we control for anemia's most common causes, we argue that the condition may also be affected by elevated levels of psychological stress.

  9. The perception of probability.

    Science.gov (United States)

    Gallistel, C R; Krishan, Monika; Liu, Ye; Miller, Reilly; Latham, Peter E

    2014-01-01

    We present a computational model to explain the results from experiments in which subjects estimate the hidden probability parameter of a stepwise nonstationary Bernoulli process outcome by outcome. The model captures the following results qualitatively and quantitatively, with only 2 free parameters: (a) Subjects do not update their estimate after each outcome; they step from one estimate to another at irregular intervals. (b) The joint distribution of step widths and heights cannot be explained on the assumption that a threshold amount of change must be exceeded in order for them to indicate a change in their perception. (c) The mapping of observed probability to the median perceived probability is the identity function over the full range of probabilities. (d) Precision (how close estimates are to the best possible estimate) is good and constant over the full range. (e) Subjects quickly detect substantial changes in the hidden probability parameter. (f) The perceived probability sometimes changes dramatically from one observation to the next. (g) Subjects sometimes have second thoughts about a previous change perception, after observing further outcomes. (h) The frequency with which they perceive changes moves in the direction of the true frequency over sessions. (Explaining this finding requires 2 additional parametric assumptions.) The model treats the perception of the current probability as a by-product of the construction of a compact encoding of the experienced sequence in terms of its change points. It illustrates the why and the how of intermittent Bayesian belief updating and retrospective revision in simple perception. It suggests a reinterpretation of findings in the recent literature on the neurobiology of decision making. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  10. Aging in bacteria, immortality or not-a critical review.

    Science.gov (United States)

    Gómez, José M G

    2010-12-01

    Bacteria were traditionally thought to have a symmetrical binary fission without a clear distinction between soma and germ-line, being thus considered as immortal biological entities. Yet it has been recently described that bacteria also undergo replicative aging (RA). That is, they exhibit finite replicative abilities under good conditions to growth. The apparently initial indistinguishability of sibling cells after cytokinesis is broken. After division, the daughter cell that inherits the "old" pole present in the "mother cell" progressively exhibits a decline in its proliferative capacity with increasing cell pole age. This is a clear hallmark and phenotypic manifestation of a bona fide RA phenomenon in toto. While the exact molecular mechanism(s) underlying to this lost of replicative potential are not yet fully understood, the "old pole cell" is considered as an aging parent that in a repeatedly manner is able to produce rejuvenated offspring which inherit a resetting of the biological clock. On the order hand, bacteria exhibit in addition to this "mandatory" RA the dubbed conditional senescence (CS). CS is defined as a decline in cellular viability observed in arrested-growing bacteria populations, a phenomenon apparently not related to RA under growing active conditions. To understand bacterial aging, it is necessary to put it within the sociality-multicellularity framework. This is a new conceptual paradigm that expresses the natural reality of the bacterial world. From this more ecological perspective these bacterial aging phenomena probably should represent an insurance/bethedging anticipative survival strategy. This is underpinned in a self-generation of an appropriate level of populational phenotypic diversity. That is, bacterial aging could be considered a communitarian adaptive response to cope with different environmental stresses and threats. I have highlighted the necessity to construct an integrative conceptual framework to achieve a unified view

  11. An evaluation method for tornado missile strike probability with stochastic correction

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Yuzuru; Murakami, Takahiro; Hirakuchi, Hiromaru; Sugimoto, Soichiro; Hattori, Yasuo [Nuclear Risk Research Center (External Natural Event Research Team), Central Research Institute of Electric Power Industry, Abiko (Japan)

    2017-03-15

    An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, QV(r), of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of QV(r) and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure.

  12. An evaluation method for tornado missile strike probability with stochastic correction

    International Nuclear Information System (INIS)

    Eguchi, Yuzuru; Murakami, Takahiro; Hirakuchi, Hiromaru; Sugimoto, Soichiro; Hattori, Yasuo

    2017-01-01

    An efficient evaluation method for the probability of a tornado missile strike without using the Monte Carlo method is proposed in this paper. A major part of the proposed probability evaluation is based on numerical results computed using an in-house code, Tornado-borne missile analysis code, which enables us to evaluate the liftoff and flight behaviors of unconstrained objects on the ground driven by a tornado. Using the Tornado-borne missile analysis code, we can obtain a stochastic correlation between local wind speed and flight distance of each object, and this stochastic correlation is used to evaluate the conditional strike probability, QV(r), of a missile located at position r, where the local wind speed is V. In contrast, the annual exceedance probability of local wind speed, which can be computed using a tornado hazard analysis code, is used to derive the probability density function, p(V). Then, we finally obtain the annual probability of tornado missile strike on a structure with the convolutional integration of product of QV(r) and p(V) over V. The evaluation method is applied to a simple problem to qualitatively confirm the validity, and to quantitatively verify the results for two extreme cases in which an object is located just in the vicinity of or far away from the structure

  13. Introduction to probability with R

    CERN Document Server

    Baclawski, Kenneth

    2008-01-01

    FOREWORD PREFACE Sets, Events, and Probability The Algebra of Sets The Bernoulli Sample Space The Algebra of Multisets The Concept of Probability Properties of Probability Measures Independent Events The Bernoulli Process The R Language Finite Processes The Basic Models Counting Rules Computing Factorials The Second Rule of Counting Computing Probabilities Discrete Random Variables The Bernoulli Process: Tossing a Coin The Bernoulli Process: Random Walk Independence and Joint Distributions Expectations The Inclusion-Exclusion Principle General Random Variable

  14. Applied probability and stochastic processes

    CERN Document Server

    Sumita, Ushio

    1999-01-01

    Applied Probability and Stochastic Processes is an edited work written in honor of Julien Keilson. This volume has attracted a host of scholars in applied probability, who have made major contributions to the field, and have written survey and state-of-the-art papers on a variety of applied probability topics, including, but not limited to: perturbation method, time reversible Markov chains, Poisson processes, Brownian techniques, Bayesian probability, optimal quality control, Markov decision processes, random matrices, queueing theory and a variety of applications of stochastic processes. The book has a mixture of theoretical, algorithmic, and application chapters providing examples of the cutting-edge work that Professor Keilson has done or influenced over the course of his highly-productive and energetic career in applied probability and stochastic processes. The book will be of interest to academic researchers, students, and industrial practitioners who seek to use the mathematics of applied probability i...

  15. Constructing diagnostic likelihood: clinical decisions using subjective versus statistical probability.

    Science.gov (United States)

    Kinnear, John; Jackson, Ruth

    2017-07-01

    Although physicians are highly trained in the application of evidence-based medicine, and are assumed to make rational decisions, there is evidence that their decision making is prone to biases. One of the biases that has been shown to affect accuracy of judgements is that of representativeness and base-rate neglect, where the saliency of a person's features leads to overestimation of their likelihood of belonging to a group. This results in the substitution of 'subjective' probability for statistical probability. This study examines clinicians' propensity to make estimations of subjective probability when presented with clinical information that is considered typical of a medical condition. The strength of the representativeness bias is tested by presenting choices in textual and graphic form. Understanding of statistical probability is also tested by omitting all clinical information. For the questions that included clinical information, 46.7% and 45.5% of clinicians made judgements of statistical probability, respectively. Where the question omitted clinical information, 79.9% of clinicians made a judgement consistent with statistical probability. There was a statistically significant difference in responses to the questions with and without representativeness information (χ2 (1, n=254)=54.45, pprobability. One of the causes for this representativeness bias may be the way clinical medicine is taught where stereotypic presentations are emphasised in diagnostic decision making. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. Pretest probability of a normal echocardiography: validation of a simple and practical algorithm for routine use.

    Science.gov (United States)

    Hammoudi, Nadjib; Duprey, Matthieu; Régnier, Philippe; Achkar, Marc; Boubrit, Lila; Preud'homme, Gisèle; Healy-Brucker, Aude; Vignalou, Jean-Baptiste; Pousset, Françoise; Komajda, Michel; Isnard, Richard

    2014-02-01

    Management of increased referrals for transthoracic echocardiography (TTE) examinations is a challenge. Patients with normal TTE examinations take less time to explore than those with heart abnormalities. A reliable method for assessing pretest probability of a normal TTE may optimize management of requests. To establish and validate, based on requests for examinations, a simple algorithm for defining pretest probability of a normal TTE. In a retrospective phase, factors associated with normality were investigated and an algorithm was designed. In a prospective phase, patients were classified in accordance with the algorithm as being at high or low probability of having a normal TTE. In the retrospective phase, 42% of 618 examinations were normal. In multivariable analysis, age and absence of cardiac history were associated to normality. Low pretest probability of normal TTE was defined by known cardiac history or, in case of doubt about cardiac history, by age>70 years. In the prospective phase, the prevalences of normality were 72% and 25% in high (n=167) and low (n=241) pretest probability of normality groups, respectively. The mean duration of normal examinations was significantly shorter than abnormal examinations (13.8 ± 9.2 min vs 17.6 ± 11.1 min; P=0.0003). A simple algorithm can classify patients referred for TTE as being at high or low pretest probability of having a normal examination. This algorithm might help to optimize management of requests in routine practice. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  17. Volatile Organic Compounds from Logwood Combustion: Emissions and Transformation under Dark and Photochemical Aging Conditions in a Smog Chamber.

    Science.gov (United States)

    Hartikainen, Anni; Yli-Pirilä, Pasi; Tiitta, Petri; Leskinen, Ari; Kortelainen, Miika; Orasche, Jürgen; Schnelle-Kreis, Jürgen; Lehtinen, Kari E J; Zimmermann, Ralf; Jokiniemi, Jorma; Sippula, Olli

    2018-04-17

    Residential wood combustion (RWC) emits high amounts of volatile organic compounds (VOCs) into ambient air, leading to formation of secondary organic aerosol (SOA), and various health and climate effects. In this study, the emission factors of VOCs from a logwood-fired modern masonry heater were measured using a Proton-Transfer-Reactor Time-of-Flight Mass Spectrometer. Next, the VOCs were aged in a 29 m 3 Teflon chamber equipped with UV black lights, where dark and photochemical atmospheric conditions were simulated. The main constituents of the VOC emissions were carbonyls and aromatic compounds, which accounted for 50%-52% and 30%-46% of the detected VOC emission, respectively. Emissions were highly susceptible to different combustion conditions, which caused a 2.4-fold variation in emission factors. The overall VOC concentrations declined considerably during both dark and photochemical aging, with simultaneous increase in particulate organic aerosol mass. Especially furanoic and phenolic compounds decreased, and they are suggested to be the major precursors of RWC-originated SOA in all aging conditions. On the other hand, dark aging produced relatively high amounts of nitrogen-containing organic compounds in both gas and particulate phase, while photochemical aging increased especially the concentrations of certain gaseous carbonyls, particularly acid anhydrides.

  18. A Semi-Continuous State-Transition Probability HMM-Based Voice Activity Detector

    Directory of Open Access Journals (Sweden)

    H. Othman

    2007-02-01

    Full Text Available We introduce an efficient hidden Markov model-based voice activity detection (VAD algorithm with time-variant state-transition probabilities in the underlying Markov chain. The transition probabilities vary in an exponential charge/discharge scheme and are softly merged with state conditional likelihood into a final VAD decision. Working in the domain of ITU-T G.729 parameters, with no additional cost for feature extraction, the proposed algorithm significantly outperforms G.729 Annex B VAD while providing a balanced tradeoff between clipping and false detection errors. The performance compares very favorably with the adaptive multirate VAD, option 2 (AMR2.

  19. A Semi-Continuous State-Transition Probability HMM-Based Voice Activity Detector

    Directory of Open Access Journals (Sweden)

    Othman H

    2007-01-01

    Full Text Available We introduce an efficient hidden Markov model-based voice activity detection (VAD algorithm with time-variant state-transition probabilities in the underlying Markov chain. The transition probabilities vary in an exponential charge/discharge scheme and are softly merged with state conditional likelihood into a final VAD decision. Working in the domain of ITU-T G.729 parameters, with no additional cost for feature extraction, the proposed algorithm significantly outperforms G.729 Annex B VAD while providing a balanced tradeoff between clipping and false detection errors. The performance compares very favorably with the adaptive multirate VAD, option 2 (AMR2.

  20. Probability of obliteration and management risk following gamma knife surgery for cerebral AVM

    International Nuclear Information System (INIS)

    Karlsson, B.; Lax, I.

    1998-01-01

    In order to define the optimal treatment for an AVM patient, the probability of cure and the management risk following the treatment must be estimated before the treatment. Here, Gamma Knife surgery has an advantage over microsurgery and embolization with it's reproducibility within the variability of the individual radiation sensitivity. Based on more than 2000 treatments, we have developed models to predict the probability for obliteration, the risk for radioinduced complications and the probability for a post treatment hemorrhage within the first two years following a Gamma Knife treatment. The factors determining the overall outcome are the absorbed dose in the target and the brain, the AVM volume and location and the age and clinical history of the patient. The probability for obliteration equals 35,69 * ln(D min )-39,66 and is AVM volume independent. The risk for radioinduced complications relates to the average dose in the 20 cm 3 tissue receiving the most radiation, and it is also related to the clinical history of the patient and the AVM location. Finally, the risk for post treatment hemorrhage increases with the age of the patient, and is higher for larger AVM. It decreases with increasing amount of radiation given, and it is independent of the clinical history of the patient. For retreatments, the model for prediction of obliteration is valid, but the risk for radioinduced complications is higher and the risk for post treatment hemorrhage lower as compared to following the first treatment. (author)

  1. First Passage Probability Estimation of Wind Turbines by Markov Chain Monte Carlo

    DEFF Research Database (Denmark)

    Sichani, Mahdi Teimouri; Nielsen, Søren R.K.

    2013-01-01

    Markov Chain Monte Carlo simulation has received considerable attention within the past decade as reportedly one of the most powerful techniques for the first passage probability estimation of dynamic systems. A very popular method in this direction capable of estimating probability of rare events...... of the method by modifying the conditional sampler. In this paper, applicability of the original SS is compared to the recently introduced modifications of the method on a wind turbine model. The model incorporates a PID pitch controller which aims at keeping the rotational speed of the wind turbine rotor equal...... to its nominal value. Finally Monte Carlo simulations are performed which allow assessment of the accuracy of the first passage probability estimation by the SS methods....

  2. Modeling take-over performance in level 3 conditionally automated vehicles.

    Science.gov (United States)

    Gold, Christian; Happee, Riender; Bengler, Klaus

    2017-11-28

    Taking over vehicle control from a Level 3 conditionally automated vehicle can be a demanding task for a driver. The take-over determines the controllability of automated vehicle functions and thereby also traffic safety. This paper presents models predicting the main take-over performance variables take-over time, minimum time-to-collision, brake application and crash probability. These variables are considered in relation to the situational and driver-related factors time-budget, traffic density, non-driving-related task, repetition, the current lane and driver's age. Regression models were developed using 753 take-over situations recorded in a series of driving simulator experiments. The models were validated with data from five other driving simulator experiments of mostly unrelated authors with another 729 take-over situations. The models accurately captured take-over time, time-to-collision and crash probability, and moderately predicted the brake application. Especially the time-budget, traffic density and the repetition strongly influenced the take-over performance, while the non-driving-related tasks, the lane and drivers' age explained a minor portion of the variance in the take-over performances. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Revisiting the impact of macroeconomic conditions on health behaviours.

    Science.gov (United States)

    Di Pietro, Giorgio

    2018-02-01

    This paper estimates the average population effect of macroeconomic conditions on health behaviours accounting for the heterogeneous impact of the business cycle on individuals. While previous studies use models relying on area-specific unemployment rates to estimate this average effect, this paper employs a model based on area-specific unemployment rates by gender and age group. The rationale for breaking down unemployment rates is that the severity of cyclical upturns and downturns does not only significantly vary across geographical areas, but also across gender and age. The empirical analysis uses microdata from the Italian Multipurpose Household Survey on Everyday Life Issues. The estimates suggest that models employing aggregated and disaggregated unemployment rate measures as a proxy for the business cycle produce similar findings for some health behaviours (such as smoking), whereas different results are obtained for others. While using unemployment rates by gender and age group, fruits and/or vegetables consumption turns out to be procyclical (a 1pp increase in this unemployment rate decreases the probability of consuming at least five daily fruit and/or vegetable servings by 0.0016pp), the opposite effect, though statistically insignificant, is observed once general unemployment rates are used. While both models conclude that physical activity declines during economic downturns, the size of the procyclical effect is much smaller when employing disaggregated rather than aggregated unemployment rates (a 1pp increase in the unemployment rate by gender and age group decreases the probability of doing any physical activity by 0.0017pp). Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Collision Probability Analysis

    DEFF Research Database (Denmark)

    Hansen, Peter Friis; Pedersen, Preben Terndrup

    1998-01-01

    It is the purpose of this report to apply a rational model for prediction of ship-ship collision probabilities as function of the ship and the crew characteristics and the navigational environment for MS Dextra sailing on a route between Cadiz and the Canary Islands.The most important ship and crew...... characteristics are: ship speed, ship manoeuvrability, the layout of the navigational bridge, the radar system, the number and the training of navigators, the presence of a look out etc. The main parameters affecting the navigational environment are ship traffic density, probability distributions of wind speeds...... probability, i.e. a study of the navigator's role in resolving critical situations, a causation factor is derived as a second step.The report documents the first step in a probabilistic collision damage analysis. Future work will inlcude calculation of energy released for crushing of structures giving...

  5. Algorithms for the extension of precise and imprecise conditional probability assessments: an implementation with maple V

    Directory of Open Access Journals (Sweden)

    Veronica Biazzo

    2000-05-01

    Full Text Available In this paper, we illustrate an implementation with Maple V of some procedures which allow to exactly propagate precise and imprecise probability assessments. The extension of imprecise assessments is based on a suitable generalization of the concept of coherence of de Finetti. The procedures described are supported by some examples and relevant cases.

  6. An extended car-following model considering the appearing probability of truck and driver's characteristics

    Science.gov (United States)

    Rong, Ying; Wen, Huiying

    2018-05-01

    In this paper, the appearing probability of truck is introduced and an extended car-following model is presented to analyze the traffic flow based on the consideration of driver's characteristics, under honk environment. The stability condition of this proposed model is obtained through linear stability analysis. In order to study the evolution properties of traffic wave near the critical point, the mKdV equation is derived by the reductive perturbation method. The results show that the traffic flow will become more disorder for the larger appearing probability of truck. Besides, the appearance of leading truck affects not only the stability of traffic flow, but also the effect of other aspects on traffic flow, such as: driver's reaction and honk effect. The effects of them on traffic flow are closely correlated with the appearing probability of truck. Finally, the numerical simulations under the periodic boundary condition are carried out to verify the proposed model. And they are consistent with the theoretical findings.

  7. PREDICTION OF RESERVOIR FLOW RATE OF DEZ DAM BY THE PROBABILITY MATRIX METHOD

    Directory of Open Access Journals (Sweden)

    Mohammad Hashem Kanani

    2012-12-01

    Full Text Available The data collected from the operation of existing storage reservoirs, could offer valuable information for the better allocation and management of fresh water rates for future use to mitigation droughts effect. In this paper the long-term Dez reservoir (IRAN water rate prediction is presented using probability matrix method. Data is analyzed to find the probability matrix of water rates in Dez reservoir based on the previous history of annual water entrance during the past and present years(40 years. The algorithm developed covers both, the overflow and non-overflow conditions in the reservoir. Result of this study shows that in non-overflow conditions the most exigency case is equal to 75%. This means that, if the reservoir is empty (the stored water is less than 100 MCM this year, it would be also empty by 75% next year. The stored water in the reservoir would be less than 300 MCM by 85% next year if the reservoir is empty this year. This percentage decreases to 70% next year if the water of reservoir is less than 300 MCM this year. The percentage also decreases to 5% next year if the reservoir is full this year. In overflow conditions the most exigency case is equal to 75% again. The reservoir volume would be less than 150 MCM by 90% next year, if it is empty this year. This percentage decreases to 70% if its water volume is less than 300 MCM and 55% if the water volume is less than 500 MCM this year. Result shows that too, if the probability matrix of water rates to a reservoir is multiplied by itself repeatedly; it converges to a constant probability matrix, which could be used to predict the long-term water rate of the reservoir. In other words, the probability matrix of series of water rates is changed to a steady probability matrix in the course of time, which could reflect the hydrological behavior of the watershed and could be easily used for the long-term prediction of water storage in the down stream reservoirs.

  8. Failure probability under parameter uncertainty.

    Science.gov (United States)

    Gerrard, R; Tsanakas, A

    2011-05-01

    In many problems of risk analysis, failure is equivalent to the event of a random risk factor exceeding a given threshold. Failure probabilities can be controlled if a decisionmaker is able to set the threshold at an appropriate level. This abstract situation applies, for example, to environmental risks with infrastructure controls; to supply chain risks with inventory controls; and to insurance solvency risks with capital controls. However, uncertainty around the distribution of the risk factor implies that parameter error will be present and the measures taken to control failure probabilities may not be effective. We show that parameter uncertainty increases the probability (understood as expected frequency) of failures. For a large class of loss distributions, arising from increasing transformations of location-scale families (including the log-normal, Weibull, and Pareto distributions), the article shows that failure probabilities can be exactly calculated, as they are independent of the true (but unknown) parameters. Hence it is possible to obtain an explicit measure of the effect of parameter uncertainty on failure probability. Failure probability can be controlled in two different ways: (1) by reducing the nominal required failure probability, depending on the size of the available data set, and (2) by modifying of the distribution itself that is used to calculate the risk control. Approach (1) corresponds to a frequentist/regulatory view of probability, while approach (2) is consistent with a Bayesian/personalistic view. We furthermore show that the two approaches are consistent in achieving the required failure probability. Finally, we briefly discuss the effects of data pooling and its systemic risk implications. © 2010 Society for Risk Analysis.

  9. Estimation of component failure probability from masked binomial system testing data

    International Nuclear Information System (INIS)

    Tan Zhibin

    2005-01-01

    The component failure probability estimates from analysis of binomial system testing data are very useful because they reflect the operational failure probability of components in the field which is similar to the test environment. In practice, this type of analysis is often confounded by the problem of data masking: the status of tested components is unknown. Methods in considering this type of uncertainty are usually computationally intensive and not practical to solve the problem for complex systems. In this paper, we consider masked binomial system testing data and develop a probabilistic model to efficiently estimate component failure probabilities. In the model, all system tests are classified into test categories based on component coverage. Component coverage of test categories is modeled by a bipartite graph. Test category failure probabilities conditional on the status of covered components are defined. An EM algorithm to estimate component failure probabilities is developed based on a simple but powerful concept: equivalent failures and tests. By simulation we not only demonstrate the convergence and accuracy of the algorithm but also show that the probabilistic model is capable of analyzing systems in series, parallel and any other user defined structures. A case study illustrates an application in test case prioritization

  10. Review of probable maximum flood definition at B.C. Hydro

    International Nuclear Information System (INIS)

    Keenhan, P.T.; Kroeker, M.G.; Neudorf, P.A.

    1991-01-01

    Probable maximum floods (PMF) have been derived for British Columbia Hydro structures since design of the W.C. Bennet Dam in 1965. A dam safety program for estimating PMF for structures designed before that time has been ongoing since 1979. The program, which has resulted in rehabilitative measures at dams not meeting current established standards, is now being directed at the more recently constructed larger structures on the Peace and Columbia rivers. Since 1965 detailed studies have produced 23 probable maximum precipitation (PMP) and 24 PMF estimates. What defines a PMF in British Columbia in terms of an appropriate combination of meteorological conditions varies due to basin size and the climatic effect of mountain barriers. PMP is estimated using three methods: storm maximization and transposition, orographic separation method, and modification of non-orographic PMP for orography. Details of, and problems encountered with, these methods are discussed. Tools or methods to assess meterological limits for antecedant conditions and for limits to runoff during extreme events have not been developed and require research effort. 11 refs., 2 figs., 3 tabs

  11. Southern pine beetle infestation probability mapping using weights of evidence analysis

    Science.gov (United States)

    Jason B. Grogan; David L. Kulhavy; James C. Kroll

    2010-01-01

    Weights of Evidence (WofE) spatial analysis was used to predict probability of southern pine beetle (Dendroctonus frontalis) (SPB) infestation in Angelina, Nacogdoches, San Augustine and Shelby Co., TX. Thematic data derived from Landsat imagery (1974–2002 Landsat 1–7) were used. Data layers included: forest covertype, forest age, forest patch size...

  12. Anomalous transport in cellular flows: The role of initial conditions and aging

    Science.gov (United States)

    Pöschke, Patrick; Sokolov, Igor M.; Nepomnyashchy, Alexander A.; Zaks, Michael A.

    2016-09-01

    We consider the diffusion-advection problem in two simple cellular flow models (often invoked as examples of subdiffusive tracer motion) and concentrate on the intermediate time range, in which the tracer motion indeed may show subdiffusion. We perform extensive numerical simulations of the systems under different initial conditions and show that the pure intermediate-time subdiffusion regime is only evident when the particles start at the border between different cells, i.e., at the separatrix, and is less pronounced or absent for other initial conditions. The motion moreover shows quite peculiar aging properties, which are also mirrored in the behavior of the time-averaged mean squared displacement for single trajectories. This kind of behavior is due to the complex motion of tracers trapped inside the cell and is absent in classical models based on continuous-time random walks with no dynamics in the trapped state.

  13. A method for estimating failure rates for low probability events arising in PSA

    International Nuclear Information System (INIS)

    Thorne, M.C.; Williams, M.M.R.

    1995-01-01

    The authors develop a method for predicting failure rates and failure probabilities per event when, over a given test period or number of demands, no failures have occurred. A Bayesian approach is adopted to calculate a posterior probability distribution for the failure rate or failure probability per event subsequent to the test period. This posterior is then used to estimate effective failure rates or probabilities over a subsequent period of time or number of demands. In special circumstances, the authors results reduce to the well-known rules of thumb, viz: 1/N and 1/T, where N is the number of demands during the test period for no failures and T is the test period for no failures. However, the authors are able to give strict conditions on the validity of these rules of thumb and to improve on them when necessary

  14. THE MODEL OF MOTOR ACTIVITY OPTIMIZATION OF YOUNGER SCHOOL AGE CHILDREN LIVING IN THE CONDITIONS OF THE NORTHERN CITY

    Directory of Open Access Journals (Sweden)

    Zhanna Ildarovna Busheva

    2017-10-01

    Full Text Available Extreme conditions of the North, computerization, Internet and a gadget dependence, high physical and intellectual loads of children activities living in the north negatively affect younger generation health state. It is difficult to overestimate a role of motor activity in expansion of functionality of the developing organism as the lack of locomotion can lead to pathological shifts in an organism. Based on the study of the concept of a ‘motor activity’ and features North of the city the article suggests a model of motor activity optimization of younger school age children living in the conditions of the northern city. It consisted of 6 units related to goal-setting, diagnostic-analytical, concept, process-activity, reflexive-evaluative and effective. The research was conducted on the basis of Surgut city schools and the Surgut region of Khanty-Mansi Autonomous Region-Yugra. During the research we revealed the most priority organization forms of motor activity of younger school age children living in conditions of the northern city. The model of motor activity optimization of younger school age children allows to create necessary optimum volume and to control of motor activity of children of younger school age. Purpose. The purpose of our research was to create model of motor activity optimization of younger school age children living in the conditions of the northern city. Methodology. Analysis and synthesis of the materials as well as the method of simulation are used as the main instruments. Results. A model of motor activity optimization of younger school age children has been elaborated in the course of study and its characteristics have been specified. Practical implications. The results can be of use for teachers at professional educational institutions.

  15. Relation between motility, accelerated aging and gene expression in selected Drosophila strains under hypergravity conditions

    NARCIS (Netherlands)

    Serrano, P.; van Loon, J.J.W.A.; Javier Medina, F.; Herranz, R.

    2013-01-01

    Motility and aging in Drosophila have proven to be highly modified under altered gravity conditions (both in space and ground simulation facilities). In order to find out how closely connected they are, five strains with altered geotactic response or survival rates were selected and exposed to an

  16. Some possible causes and probability of leakages in LMFBR steam generators

    International Nuclear Information System (INIS)

    Bolt, P.R.

    1984-01-01

    Relevant operational experience with steam generators for process and conventional plant and thermal and fast reactors is reviewed. Possible causes of water/steam leakages into sodium/gas are identified and data is given on the conditions necessary for failure, leakage probability and type of leakage path. (author)

  17. Hygienic characteristics of working conditions and their influence on biological age of women occupied in modern wallpaper industry

    Directory of Open Access Journals (Sweden)

    Pichugina N.N.

    2011-06-01

    Full Text Available The article presents a complex sanitary characteristic of working conditions of women involved in wallpaper production. The main favorable factors of industrial environment have been determined. It is shown that working conditions in wallpaper production factories cause an increase in indices of biological age

  18. Probability theory for 3-layer remote sensing in ideal gas law environment.

    Science.gov (United States)

    Ben-David, Avishai; Davidson, Charles E

    2013-08-26

    We extend the probability model for 3-layer radiative transfer [Opt. Express 20, 10004 (2012)] to ideal gas conditions where a correlation exists between transmission and temperature of each of the 3 layers. The effect on the probability density function for the at-sensor radiances is surprisingly small, and thus the added complexity of addressing the correlation can be avoided. The small overall effect is due to (a) small perturbations by the correlation on variance population parameters and (b) cancellation of perturbation terms that appear with opposite signs in the model moment expressions.

  19. Operating envelope to minimize probability of fractures in Zircaloy-2 pressure tubes

    International Nuclear Information System (INIS)

    Azer, N.; Wong, H.

    1994-01-01

    The failure mode of primary concern with Candu pressure tubes is fast fracture of a through-wall axial crack, resulting from delayed hydride crack growth. The application of operating envelopes is demonstrated to minimize the probability of fracture in Zircaloy-2 pressure tubes based on Zr-2.5%Nb pressure tube experience. The technical basis for the development of the operating envelopes is also summarized. The operating envelope represents an area on the pressure versus temperature diagram within which the reactor may be operated without undue concern for pressure tube fracture. The envelopes presented address both normal operating conditions and the condition where a pressure tube leak has been detected. The examples in this paper are prepared to illustrate the methodology, and are not intended to be directly applicable to the operation of any specific reactor. The application of operating envelopes to minimized the probability of fracture in 80 mm diameter Zircaloy-2 pressure tubes has been discussed. Both normal operating and leaking pressure tube conditions have been considered. 3 refs., 4 figs

  20. Nuclear power plant ageing and life extension: Safety aspects

    International Nuclear Information System (INIS)

    Novak, S.; Podest, M.

    1987-01-01

    Experience with large fossil-fired electrical generating units, as well as in all process industries, shows that plants begin to deteriorate with age after approximately 10 years of operation. Similar phenomena will prevail for nuclear plants, and it is reasonable to postulate that their availability will be affected, as will their safety, if appropriate measures are not taken. It is evident that the average age of power reactors in the IAEA's Member States is increasing. By 2000, more than 50 nuclear plants will have been providing electricity for 25 years or longer. Most nuclear power plants have operating lifetimes of between 20 and 40 years. Ageing is defined as a continuing time-dependent degradation of material due to service conditions, including normal operation and transient conditions. It is common experience that over long periods of time, there is a gradual change in the properties of materials. These changes can affect the capability of engineered components, systems, or structures to perform their required function. Not all changes are deleterious, but it is commonly observed that ageing processes normally involve a gradual reduction in performance capability. All materials in a nuclear power plant can suffer from ageing and can partially or totally lose their designed function. Ageing is not only of concern for active components (for which the probability of malfunction increases with time) but also for passive ones, since the safety margin is being reduced towards the lowest allowable level

  1. Metallurgical properties of reduced activation martensitic steel Eurofer'97 in the as-received condition and after thermal ageing

    International Nuclear Information System (INIS)

    Fernandez, P.; Lancha, A.M.; Lapena, J.; Serrano, M.; Hernandez-Mayoral, M.

    2002-01-01

    This paper describes the microstructural studies and the mechanical testing (hardness, tensile and charpy tests) performed on the Eurofer'97 steel in the as-received condition and after thermal ageing treatments up to 600 deg. C. In addition, fracture toughness tests on the as-received condition have been carried out in order to determine the Master Curve. During the thermal ageing treatments studied (500 deg. C/5000 h and 600 deg. C/1000 h) the general microstructure of the steel (tempered martensite with M 23 C 6 and MX precipitates) remained stable. Only a slight growth of the particles has been observed. In terms of mechanical properties, the Eurofer'97 steel exhibited similar values of tensile properties (tensile and yield strength) and ductile-brittle transition temperature regardless of the material condition studied.

  2. [Effects of prefrontal ablations on the reaction of the active choice of feeder under different probability and value of the reinforcement on dog].

    Science.gov (United States)

    Preobrazhenskaia, L A; Ioffe, M E; Mats, V N

    2004-01-01

    The role of the prefrontal cortex was investigated on the reaction of the active choice of the two feeders under changes value and probability reinforcement. The experiments were performed on 2 dogs with prefrontal ablation (g. proreus). Before the lesions the dogs were taught to receive food in two different feeders to conditioned stimuli with equally probable alimentary reinforcement. After ablation in the inter-trial intervals the dogs were running from the one feeder to another. In the answer to conditioned stimuli for many times the dogs choose the same feeder. The disturbance of the behavior after some times completely restored. In the experiments with competition of probability events and values of reinforcement the dogs chose the feeder with low-probability but better quality of reinforcement. In the experiments with equal value but different probability the intact dogs chose the feeder with higher probability. In our experiments the dogs with prefrontal lesions chose the each feeder equiprobably. Thus in condition of free behavior one of different functions of the prefrontal cortex is the reactions choose with more probability of reinforcement.

  3. The Dynamic contribution of chronic conditions to temporal trends in disability among U.S. adults.

    Science.gov (United States)

    Lin, Shih-Fan; Beck, Audrey N; Finch, Brian K

    2016-04-01

    Although evidence has shown that U.S. late-life disability has been declining, studies have also suggested that there has been an increase in chronic diseases between 1984 and 2007. To further illuminate these potentially contradictory trends, we explicate how the contribution of chronic conditions changes across four common types of disability (ADL, IADL, mobility disability, and functional limitations) by age (A), period (P), and birth cohorts (C) among adults aged 20 and above. Our data came from seven cross-sectional waves of the National Health and Nutrition Examination Survey (NHANES). We utilize a cross-classified random effect model (CCREM) to simultaneously estimate age, period, and cohort trends for each disability. Each chronic condition was sequentially then simultaneously added to our base models (sociodemographics only). Reductions in predicted probability from the base model were then calculated for each chronic condition by each temporal dimension (A/P/C) to assess the contribution of each chronic condition. There was increasing age-based contribution of chronic conditions to all disabilities. The period-based contribution remained quite stagnant across years while cohort-based contributions showed a continual decline for recent cohorts. Arthritis showed the greatest contribution to disability of all types which was followed by obesity. Cancer was the least important contributor to disabilities. Although chronic conditions are becoming less disabling across recent cohorts, other competing risk factors might suggest prevailing causes of disability. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. A Methodology for Modeling Nuclear Power Plant Passive Component Aging in Probabilistic Risk Assessment under the Impact of Operating Conditions, Surveillance and Maintenance Activities

    Science.gov (United States)

    Guler Yigitoglu, Askin

    multi-state physics based model is selected to represent the aging process. The model is modified via sojourn time approach to reflect the operational and maintenance history dependence of the transition rates. Thermal-hydraulic parameters of the model are calculated via the reactor simulation environment and uncertainties associated with both parameters and the models are assessed via a two-loop Monte Carlo approach (Latin hypercube sampling) to propagate input probability distributions through the physical model. The effort documented in this thesis towards this overall objective consists of : i) defining a process for selecting critical passive components and related aging mechanisms, ii) aging model selection, iii) calculating the probability that aging would cause the component to fail, iv) uncertainty/sensitivity analyses, v) procedure development for modifying an existing PRA to accommodate consideration of passive component failures, and, vi) including the calculated failure probability in the modified PRA. The proposed methodology is applied to pressurizer surge line pipe weld aging and steam generator tube degradation in pressurized water reactors.

  5. On estimating probability of presence from use-availability or presence-background data.

    Science.gov (United States)

    Phillips, Steven J; Elith, Jane

    2013-06-01

    A fundamental ecological modeling task is to estimate the probability that a species is present in (or uses) a site, conditional on environmental variables. For many species, available data consist of "presence" data (locations where the species [or evidence of it] has been observed), together with "background" data, a random sample of available environmental conditions. Recently published papers disagree on whether probability of presence is identifiable from such presence-background data alone. This paper aims to resolve the disagreement, demonstrating that additional information is required. We defined seven simulated species representing various simple shapes of response to environmental variables (constant, linear, convex, unimodal, S-shaped) and ran five logistic model-fitting methods using 1000 presence samples and 10 000 background samples; the simulations were repeated 100 times. The experiment revealed a stark contrast between two groups of methods: those based on a strong assumption that species' true probability of presence exactly matches a given parametric form had highly variable predictions and much larger RMS error than methods that take population prevalence (the fraction of sites in which the species is present) as an additional parameter. For six species, the former group grossly under- or overestimated probability of presence. The cause was not model structure or choice of link function, because all methods were logistic with linear and, where necessary, quadratic terms. Rather, the experiment demonstrates that an estimate of prevalence is not just helpful, but is necessary (except in special cases) for identifying probability of presence. We therefore advise against use of methods that rely on the strong assumption, due to Lele and Keim (recently advocated by Royle et al.) and Lancaster and Imbens. The methods are fragile, and their strong assumption is unlikely to be true in practice. We emphasize, however, that we are not arguing against

  6. β-cell serotonin production is associated with female sex, old age, and diabetes-free condition.

    Science.gov (United States)

    Kim, Yeong Gi; Moon, Joon Ho; Kim, Kyuho; Kim, Hyeongseok; Kim, Juok; Jeong, Ji-Seon; Lee, Junguee; Kang, Shinae; Park, Joon Seong; Kim, Hail

    2017-11-25

    Serotonin is known to be present in pancreatic β-cells and to play several physiological roles, including insulin secretion, β-cell proliferation, and paracrine inhibition of α-cells. However, the serotonin production of different cell lines and islets has not been compared based on age, sex, and diabetes related conditions. Here, we directly compared the serotonin concentrations in βTC and MIN6 cell lines, as well as in islets from mice using ultra-performance liquid chromatography tandem mass spectrometry. The average serotonin concentration was 5-10 ng/mg protein in the islets of male and non-pregnant female mice. The serotonin level was higher in females than males at 8 weeks, although there was no difference at 1 year. Furthermore, we observed serotonin by immunofluorescence staining in the pancreatic tissues of mice and human. Serotonin was detected by immunofluorescence staining in a portion of β-cells from islets of old female mice, but not of male or young female mice. A similar pattern was observed in human pancreas as well. In humans, serotonin production in β-cells was associated with a diabetes-free condition. Thus, serotonin production in β-cells was associated with old age, female sex, and diabetes-free condition. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. A first course in probability

    CERN Document Server

    Ross, Sheldon

    2014-01-01

    A First Course in Probability, Ninth Edition, features clear and intuitive explanations of the mathematics of probability theory, outstanding problem sets, and a variety of diverse examples and applications. This book is ideal for an upper-level undergraduate or graduate level introduction to probability for math, science, engineering and business students. It assumes a background in elementary calculus.

  8. Estimating Subjective Probabilities

    DEFF Research Database (Denmark)

    Andersen, Steffen; Fountain, John; Harrison, Glenn W.

    2014-01-01

    either construct elicitation mechanisms that control for risk aversion, or construct elicitation mechanisms which undertake 'calibrating adjustments' to elicited reports. We illustrate how the joint estimation of risk attitudes and subjective probabilities can provide the calibration adjustments...... that theory calls for. We illustrate this approach using data from a controlled experiment with real monetary consequences to the subjects. This allows the observer to make inferences about the latent subjective probability, under virtually any well-specified model of choice under subjective risk, while still...

  9. USING RASCH ANALYSIS TO EXPLORE WHAT STUDENTS LEARN ABOUT PROBABILITY CONCEPTS

    Directory of Open Access Journals (Sweden)

    Zamalia Mahmud

    2015-01-01

    Full Text Available Students’ understanding of probability concepts have been investigated from various different perspectives. This study was set out to investigate perceived understanding of probability concepts of forty-four students from the STAT131 Understanding Uncertainty and Variation course at the University of Wollongong, NSW. Rasch measurement which is based on a probabilistic model was used to identify concepts that students find easy, moderate and difficult to understand.  Data were captured from the e-learning Moodle platform where students provided their responses through an on-line quiz. As illustrated in the Rasch map, 96% of the students could understand about sample space, simple events, mutually exclusive events and tree diagram while 67% of the students found concepts of conditional and independent events rather easy to understand.Keywords: Perceived Understanding, Probability Concepts, Rasch Measurement Model DOI: dx.doi.org/10.22342/jme.61.1

  10. Filter-adsorber aging assessment

    Energy Technology Data Exchange (ETDEWEB)

    Winegardner, W.K. [Pacific Northwest Laboratory, Richland, WA (United States)

    1995-02-01

    An aging assessment of high-efficiency particulate (HEPA) air filters and activated carbon gas adsorption units was performed by the Pacific Northwest Laboratory as part of the U.S. Nuclear Regulatory Commission`s (USNRC) Nuclear Plant Aging Research (NPAR) Program. This evaluation of the general process in which characteristics of these two components gradually change with time or use included the compilation of information concerning failure experience, stressors, aging mechanisms and effects, and inspection, surveillance, and monitoring methods (ISMM). Stressors, the agents or stimuli that can produce aging degradation, include heat, radiation, volatile contaminants, and even normal concentrations of aerosol particles and gasses. In an experimental evaluation of degradation in terms of the tensile breaking strength of aged filter media specimens, over forty percent of the samples did not meet specifications for new material. Chemical and physical reactions can gradually embrittle sealants and gaskets as well as filter media. Mechanisms that can lead to impaired adsorber performance are associated with the loss of potentially available active sites as a result of the exposure of the carbon to airborne moisture or volatile organic compounds. Inspection, surveillance, and monitoring methods have been established to observe filter pressure drop buildup, check HEPA filters and adsorbers for bypass, and determine the retention effectiveness of aged carbon. These evaluations of installed filters do not reveal degradation in terms of reduced media strength but that under normal conditions aged media can continue to effectively retain particles. However, this degradation may be important when considering the likelihood of moisture, steam, and higher particle loadings during severe accidents and the fact it is probable that the filters have been in use for an extended period.

  11. Probability and Bayesian statistics

    CERN Document Server

    1987-01-01

    This book contains selected and refereed contributions to the "Inter­ national Symposium on Probability and Bayesian Statistics" which was orga­ nized to celebrate the 80th birthday of Professor Bruno de Finetti at his birthplace Innsbruck in Austria. Since Professor de Finetti died in 1985 the symposium was dedicated to the memory of Bruno de Finetti and took place at Igls near Innsbruck from 23 to 26 September 1986. Some of the pa­ pers are published especially by the relationship to Bruno de Finetti's scientific work. The evolution of stochastics shows growing importance of probability as coherent assessment of numerical values as degrees of believe in certain events. This is the basis for Bayesian inference in the sense of modern statistics. The contributions in this volume cover a broad spectrum ranging from foundations of probability across psychological aspects of formulating sub­ jective probability statements, abstract measure theoretical considerations, contributions to theoretical statistics an...

  12. Market-implied risk-neutral probabilities, actual probabilities, credit risk and news

    Directory of Open Access Journals (Sweden)

    Shashidhar Murthy

    2011-09-01

    Full Text Available Motivated by the credit crisis, this paper investigates links between risk-neutral probabilities of default implied by markets (e.g. from yield spreads and their actual counterparts (e.g. from ratings. It discusses differences between the two and clarifies underlying economic intuition using simple representations of credit risk pricing. Observed large differences across bonds in the ratio of the two probabilities are shown to imply that apparently safer securities can be more sensitive to news.

  13. Preimplantation genetic diagnosis: does age of onset matter (anymore)?

    Science.gov (United States)

    Krahn, Timothy

    2009-06-01

    The identification and avoidance of disease susceptibility in embryos is the most common goal of preimplantation genetic diagnosis (PGD). Most jurisdictions that accept but regulate the availability of PGD restrict it to what are characterized as 'serious' conditions. Line-drawing around seriousness is not determined solely by the identification of a genetic mutation. Other factors seen to be relevant include: impact on health or severity of symptoms; degree of penetrance (probability of genotype being expressed as a genetic disorder); potential for therapy; rate of progression; heritability; and age of onset. In the original applications of PGD, most, if not all of these factors were seen as necessary but none was seen as sufficient for determining whether a genetic condition was labelled 'serious'. This, however, is changing as impact on health or severity of symptoms is coming to eclipse the other considerations. This paper investigates how age of onset (primarily in the context of the United Kingdom (UK)) has become considerably less significant as a criterion for determining ethically acceptable applications of PGD. Having moved off the threshold of permitting PGD testing for only fatal (or seriously debilitating), early-onset diseases, I will investigate reasons for why age of onset will not do any work to discriminate between which adult-onset diseases should be considered serious or not. First I will explain the rationale underpinning age of onset as a factor to be weighed in making determinations of seriousness. Next I will challenge the view that later-onset conditions are less serious for being later than earlier-onset conditions. The final section of the paper will discuss some of the broader disability concerns at stake in limiting access to PGD based upon determinations of the 'seriousness' of genetic conditions. Instead of advocating a return to limiting PGD to only early-onset conditions, I conclude that the whole enterprise of trying to draw lines

  14. [Autonomic regulation at emotional stress under hypoxic conditions in the elderly with physiological and accelerated aging: effect of hypoxic training].

    Science.gov (United States)

    Os'mak, E D; Asanov, É O

    2014-01-01

    The effect of hypoxic training on autonomic regulation in psycho-emotional stress conditions in hypoxic conditions in older people with physiological (25 people) and accelerated (28 people) aging respiratory system. It is shown that hypoxic training leads to an increase in vagal activity indicators (HF) and reduced simpatovagal index (LF/HF), have a normalizing effect on the autonomic balance during stress loads in older people with different types of aging respiratory system.

  15. Spatial probability aids visual stimulus discrimination

    Directory of Open Access Journals (Sweden)

    Michael Druker

    2010-08-01

    Full Text Available We investigated whether the statistical predictability of a target's location would influence how quickly and accurately it was classified. Recent results have suggested that spatial probability can be a cue for the allocation of attention in visual search. One explanation for probability cuing is spatial repetition priming. In our two experiments we used probability distributions that were continuous across the display rather than relying on a few arbitrary screen locations. This produced fewer spatial repeats and allowed us to dissociate the effect of a high probability location from that of short-term spatial repetition. The task required participants to quickly judge the color of a single dot presented on a computer screen. In Experiment 1, targets were more probable in an off-center hotspot of high probability that gradually declined to a background rate. Targets garnered faster responses if they were near earlier target locations (priming and if they were near the high probability hotspot (probability cuing. In Experiment 2, target locations were chosen on three concentric circles around fixation. One circle contained 80% of targets. The value of this ring distribution is that it allowed for a spatially restricted high probability zone in which sequentially repeated trials were not likely to be physically close. Participant performance was sensitive to the high-probability circle in addition to the expected effects of eccentricity and the distance to recent targets. These two experiments suggest that inhomogeneities in spatial probability can be learned and used by participants on-line and without prompting as an aid for visual stimulus discrimination and that spatial repetition priming is not a sufficient explanation for this effect. Future models of attention should consider explicitly incorporating the probabilities of targets locations and features.

  16. Main factors for fatigue failure probability of pipes subjected to fluid thermal fluctuation

    International Nuclear Information System (INIS)

    Machida, Hideo; Suzuki, Masaaki; Kasahara, Naoto

    2015-01-01

    It is very important to grasp failure probability and failure mode appropriately to carry out risk reduction measures of nuclear power plants. To clarify the important factors for failure probability and failure mode of pipes subjected to fluid thermal fluctuation, failure probability analyses were performed by changing the values of a stress range, stress ratio, stress components and threshold of stress intensity factor range. The important factors for the failure probability are range, stress ratio (mean stress condition) and threshold of stress intensity factor range. The important factor for the failure mode is a circumferential angle range of fluid thermal fluctuation. When a large fluid thermal fluctuation acts on the entire circumferential surface of the pipe, the probability of pipe breakage increases, calling for measures to prevent such a failure and reduce the risk to the plant. When the circumferential angle subjected to fluid thermal fluctuation is small, the failure mode of piping is leakage and the corrective maintenance might be applicable from the viewpoint of risk to the plant. (author)

  17. Seed storage at elevated partial pressure of oxygen, a fast method for analysing seed ageing under dry conditions

    Science.gov (United States)

    Groot, S. P. C.; Surki, A. A.; de Vos, R. C. H.; Kodde, J.

    2012-01-01

    Background and Aims Despite differences in physiology between dry and relative moist seeds, seed ageing tests most often use a temperature and seed moisture level that are higher than during dry storage used in commercial practice and gene banks. This study aimed to test whether seed ageing under dry conditions can be accelerated by storing under high-pressure oxygen. Methods Dry barley (Hordeum vulgare), cabbage (Brassica oleracea), lettuce (Lactuca sativa) and soybean (Glycine max) seeds were stored between 2 and 7 weeks in steel tanks under 18 MPa partial pressure of oxygen. Storage under high-pressure nitrogen gas or under ambient air pressure served as controls. The method was compared with storage at 45 °C after equilibration at 85 % relative humidity and long-term storage at the laboratory bench. Germination behaviour, seedling morphology and tocopherol levels were assessed. Key Results The ageing of the dry seeds was indeed accelerated by storing under high-pressure oxygen. The morphological ageing symptoms of the stored seeds resembled those observed after ageing under long-term dry storage conditions. Barley appeared more tolerant of this storage treatment compared with lettuce and soybean. Less-mature harvested cabbage seeds were more sensitive, as was the case for primed compared with non-primed lettuce seeds. Under high-pressure oxygen storage the tocopherol levels of dry seeds decreased, in a linear way with the decline in seed germination, but remained unchanged in seeds deteriorated during storage at 45 °C after equilibration at 85 % RH. Conclusions Seed storage under high-pressure oxygen offers a novel and relatively fast method to study the physiology and biochemistry of seed ageing at different seed moisture levels and temperatures, including those that are representative of the dry storage conditions as used in gene banks and commercial practice. PMID:22967856

  18. Seed storage at elevated partial pressure of oxygen, a fast method for analysing seed ageing under dry conditions.

    Science.gov (United States)

    Groot, S P C; Surki, A A; de Vos, R C H; Kodde, J

    2012-11-01

    Despite differences in physiology between dry and relative moist seeds, seed ageing tests most often use a temperature and seed moisture level that are higher than during dry storage used in commercial practice and gene banks. This study aimed to test whether seed ageing under dry conditions can be accelerated by storing under high-pressure oxygen. methods: Dry barley (Hordeum vulgare), cabbage (Brassica oleracea), lettuce (Lactuca sativa) and soybean (Glycine max) seeds were stored between 2 and 7 weeks in steel tanks under 18 MPa partial pressure of oxygen. Storage under high-pressure nitrogen gas or under ambient air pressure served as controls. The method was compared with storage at 45 °C after equilibration at 85 % relative humidity and long-term storage at the laboratory bench. Germination behaviour, seedling morphology and tocopherol levels were assessed. The ageing of the dry seeds was indeed accelerated by storing under high-pressure oxygen. The morphological ageing symptoms of the stored seeds resembled those observed after ageing under long-term dry storage conditions. Barley appeared more tolerant of this storage treatment compared with lettuce and soybean. Less-mature harvested cabbage seeds were more sensitive, as was the case for primed compared with non-primed lettuce seeds. Under high-pressure oxygen storage the tocopherol levels of dry seeds decreased, in a linear way with the decline in seed germination, but remained unchanged in seeds deteriorated during storage at 45 °C after equilibration at 85 % RH. Seed storage under high-pressure oxygen offers a novel and relatively fast method to study the physiology and biochemistry of seed ageing at different seed moisture levels and temperatures, including those that are representative of the dry storage conditions as used in gene banks and commercial practice.

  19. Wire system ageing assessment and condition monitoring (WASCO)

    International Nuclear Information System (INIS)

    Ekelund, M; Gedde, U.W.; Fantoni, P.F.

    2011-05-01

    Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. In this report 3 techniques for cable global ageing assessment were tested and evaluated. The EAB technique is a destructive, local technique that is often used as a reference for other methods. The indenter is a local, in-situ mechanical technique that is currently quite often used in NPPs. LIRA is an electrical method, full line, in-situ. LIRA correlated quite well with EAB and both tend to flatten when the ageing time reaches 40 years. The only cable type that was difficult to assess for all the 3 methods was the medium type in air environment. These tests considered only thermal ageing, up to 50 years and should be completed by considering also gamma irradiation ageing. (Author)

  20. Wire system ageing assessment and condition monitoring (WASCO)

    Energy Technology Data Exchange (ETDEWEB)

    Ekelund, M; Gedde, U.W. (Royal Institute of Technology (KTH). Fibre and Polymer Technology, School of Chemical Science and Engineering, Stockholm (Sweden)); Fantoni, P.F. (Institute for Energy Technology (IFE), Halden (Norway))

    2011-05-15

    Nuclear facilities rely on electrical wire systems to perform a variety of functions for successful operation. Many of these functions directly support the safe operation of the facility; therefore, the continued reliability of wire systems, even as they age, is critical. In this report 3 techniques for cable global ageing assessment were tested and evaluated. The EAB technique is a destructive, local technique that is often used as a reference for other methods. The indenter is a local, in-situ mechanical technique that is currently quite often used in NPPs. LIRA is an electrical method, full line, in-situ. LIRA correlated quite well with EAB and both tend to flatten when the ageing time reaches 40 years. The only cable type that was difficult to assess for all the 3 methods was the medium type in air environment. These tests considered only thermal ageing, up to 50 years and should be completed by considering also gamma irradiation ageing. (Author)

  1. Probability, Nondeterminism and Concurrency

    DEFF Research Database (Denmark)

    Varacca, Daniele

    Nondeterminism is modelled in domain theory by the notion of a powerdomain, while probability is modelled by that of the probabilistic powerdomain. Some problems arise when we want to combine them in order to model computation in which both nondeterminism and probability are present. In particula...

  2. Ignition Probability

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — USFS, State Forestry, BLM, and DOI fire occurrence point locations from 1987 to 2008 were combined and converted into a fire occurrence probability or density grid...

  3. Reliability analysis of reactor systems by applying probability method; Analiza pouzdanosti reaktorskih sistema primenom metoda verovatnoce

    Energy Technology Data Exchange (ETDEWEB)

    Milivojevic, S [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

    1974-12-15

    Probability method was chosen for analysing the reactor system reliability is considered realistic since it is based on verified experimental data. In fact this is a statistical method. The probability method developed takes into account the probability distribution of permitted levels of relevant parameters and their particular influence on the reliability of the system as a whole. The proposed method is rather general, and was used for problem of thermal safety analysis of reactor system. This analysis enables to analyze basic properties of the system under different operation conditions, expressed in form of probability they show the reliability of the system on the whole as well as reliability of each component.

  4. Probability of Failure in Random Vibration

    DEFF Research Database (Denmark)

    Nielsen, Søren R.K.; Sørensen, John Dalsgaard

    1988-01-01

    Close approximations to the first-passage probability of failure in random vibration can be obtained by integral equation methods. A simple relation exists between the first-passage probability density function and the distribution function for the time interval spent below a barrier before out......-crossing. An integral equation for the probability density function of the time interval is formulated, and adequate approximations for the kernel are suggested. The kernel approximation results in approximate solutions for the probability density function of the time interval and thus for the first-passage probability...

  5. Musculoskeletal Health Conditions Represent a Global Threat to Healthy Aging: A Report for the 2015 World Health Organization World Report on Ageing and Health.

    Science.gov (United States)

    Briggs, Andrew M; Cross, Marita J; Hoy, Damian G; Sànchez-Riera, Lídia; Blyth, Fiona M; Woolf, Anthony D; March, Lyn

    2016-04-01

    Persistent pain, impaired mobility and function, and reduced quality of life and mental well-being are the most common experiences associated with musculoskeletal conditions, of which there are more than 150 types. The prevalence and impact of musculoskeletal conditions increase with aging. A profound burden of musculoskeletal disease exists in developed and developing nations. Notably, this burden far exceeds service capacity. Population growth, aging, and sedentary lifestyles, particularly in developing countries, will create a crisis for population health that requires a multisystem response with musculoskeletal health services as a critical component. Globally, there is an emphasis on maintaining an active lifestyle to reduce the impacts of obesity, cardiovascular conditions, cancer, osteoporosis, and diabetes in older people. Painful musculoskeletal conditions, however, profoundly limit the ability of people to make these lifestyle changes. A strong relationship exists between painful musculoskeletal conditions and a reduced capacity to engage in physical activity resulting in functional decline, frailty, reduced well-being, and loss of independence. Multilevel strategies and approaches to care that adopt a whole person approach are needed to address the impact of impaired musculoskeletal health and its sequelae. Effective strategies are available to address the impact of musculoskeletal conditions; some are of low cost (e.g., primary care-based interventions) but others are expensive and, as such, are usually only feasible for developed nations. In developing nations, it is crucial that any reform or development initiatives, including research, must adhere to the principles of development effectiveness to avoid doing harm to the health systems in these settings. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. A closer look at the probabilities of the notorious three prisoners.

    Science.gov (United States)

    Falk, R

    1992-06-01

    The "problem of three prisoners", a counterintuitive teaser, is analyzed. It is representative of a class of probability puzzles where the correct solution depends on explication of underlying assumptions. Spontaneous beliefs concerning the problem and intuitive heuristics are reviewed. The psychological background of these beliefs is explored. Several attempts to find a simple criterion to predict whether and how the probability of the target event will change as a result of obtaining evidence are examined. However, despite the psychological appeal of these attempts, none proves to be valid in general. A necessary and sufficient condition for change in the probability of the target event, following observation of new data, is proposed. That criterion is an extension of the likelihood-ratio principle (which holds in the case of only two complementary alternatives) to any number of alternatives. Some didactic implications concerning the significance of the chance set-up and reliance on analogies are discussed.

  7. The concept of probability

    International Nuclear Information System (INIS)

    Bitsakis, E.I.; Nicolaides, C.A.

    1989-01-01

    The concept of probability is now, and always has been, central to the debate on the interpretation of quantum mechanics. Furthermore, probability permeates all of science, as well as our every day life. The papers included in this volume, written by leading proponents of the ideas expressed, embrace a broad spectrum of thought and results: mathematical, physical epistemological, and experimental, both specific and general. The contributions are arranged in parts under the following headings: Following Schroedinger's thoughts; Probability and quantum mechanics; Aspects of the arguments on nonlocality; Bell's theorem and EPR correlations; Real or Gedanken experiments and their interpretation; Questions about irreversibility and stochasticity; and Epistemology, interpretation and culture. (author). refs.; figs.; tabs

  8. Choice probability generating functions

    DEFF Research Database (Denmark)

    Fosgerau, Mogens; McFadden, Daniel; Bierlaire, Michel

    2010-01-01

    This paper establishes that every random utility discrete choice model (RUM) has a representation that can be characterized by a choice-probability generating function (CPGF) with specific properties, and that every function with these specific properties is consistent with a RUM. The choice...... probabilities from the RUM are obtained from the gradient of the CPGF. Mixtures of RUM are characterized by logarithmic mixtures of their associated CPGF. The paper relates CPGF to multivariate extreme value distributions, and reviews and extends methods for constructing generating functions for applications....... The choice probabilities of any ARUM may be approximated by a cross-nested logit model. The results for ARUM are extended to competing risk survival models....

  9. Constructing inverse probability weights for continuous exposures: a comparison of methods.

    Science.gov (United States)

    Naimi, Ashley I; Moodie, Erica E M; Auger, Nathalie; Kaufman, Jay S

    2014-03-01

    Inverse probability-weighted marginal structural models with binary exposures are common in epidemiology. Constructing inverse probability weights for a continuous exposure can be complicated by the presence of outliers, and the need to identify a parametric form for the exposure and account for nonconstant exposure variance. We explored the performance of various methods to construct inverse probability weights for continuous exposures using Monte Carlo simulation. We generated two continuous exposures and binary outcomes using data sampled from a large empirical cohort. The first exposure followed a normal distribution with homoscedastic variance. The second exposure followed a contaminated Poisson distribution, with heteroscedastic variance equal to the conditional mean. We assessed six methods to construct inverse probability weights using: a normal distribution, a normal distribution with heteroscedastic variance, a truncated normal distribution with heteroscedastic variance, a gamma distribution, a t distribution (1, 3, and 5 degrees of freedom), and a quantile binning approach (based on 10, 15, and 20 exposure categories). We estimated the marginal odds ratio for a single-unit increase in each simulated exposure in a regression model weighted by the inverse probability weights constructed using each approach, and then computed the bias and mean squared error for each method. For the homoscedastic exposure, the standard normal, gamma, and quantile binning approaches performed best. For the heteroscedastic exposure, the quantile binning, gamma, and heteroscedastic normal approaches performed best. Our results suggest that the quantile binning approach is a simple and versatile way to construct inverse probability weights for continuous exposures.

  10. Collective fluctuations in magnetized plasma: Transition probability approach

    International Nuclear Information System (INIS)

    Sosenko, P.P.

    1997-01-01

    Statistical plasma electrodynamics is elaborated with special emphasis on the transition probability approach and quasi-particles, and on modern applications to magnetized plasmas. Fluctuation spectra in the magnetized plasma are calculated in the range of low frequencies (with respect to the cyclotron one), and the conditions for the transition from incoherent to collective fluctuations are established. The role of finite-Larmor-radius effects and particle polarization drift in such a transition is explained. The ion collective features in fluctuation spectra are studied. 63 refs., 30 figs

  11. [Is it possible to "cancel" aging process of cell cultures under optimal conditions for cultivation?].

    Science.gov (United States)

    Bozhkov, A I; Kovaleva, M K; Menzianova, N G

    2011-01-01

    The characteristics of the cells epigenotypes Dunaliella viridis Teod. in the process of chronological and replicative aging were investigated. By 40th day of accumulative cultivation (which coincided with the stationary growth phase) DNA content in the cells of Dunaliella viridis increased 2 times, triacylglycerides 3 times, beta-carotene and carbonyl proteins 2 times, RNA content decreased in comparison with cells in exponential growth phase, i. e., the 40th day of growth of culture forms the age-related epigenotype. 4 received subcultures were being transplanted during 2 years in mid-logarithmic growth phase (subculture-10), early stationary phase of growth (subculture-20), in the mid-stationary growth phase (subculture-30), and late stationary growth phase (subculture-40). It is shown that epigenotype of subculture-10 remained unchanged over 2 years of cultivation, i. e., it does not manifest replicative aging. At the same time, the subculture-20, although long enough (at least 40 passages), maintained epigenotype characteristic of young cultures, and showed age-related changes. Pronounced age-dependent changes of epigenotype in the course of cultivation were identified for subculture-30, and subculture-40 was characterized by unstable epigenotype. Thus, cultivation conditions determine the intensity of replicative aging in Dunaliella viridis.

  12. Ageing evaluation model of nuclear reactors structural elements

    International Nuclear Information System (INIS)

    Ziliukas, A.; Jutas, A.; Leisis, V.

    2002-01-01

    In this article the estimation of non-failure probability by random faults on the structural elements of nuclear reactors is presented. Ageing is certainly a significant factor in determining the limits of nuclear plant lifetime or life extensions. Usually the non failure probability rates failure intensity, which is characteristic for structural elements ageing in nuclear reactors. In practice the reliability is increased incorrectly because not all failures are fixed and cumulated. Therefore, the methodology with using the fine parameter of the failures flow is described. The comparison of non failure probability and failures flow is carried out. The calculation of these parameters in the practical example is shown too. (author)

  13. Relation Between Motility, Accelerated Aging and Gene Expression in Selected Drosophila Strains under Hypergravity Conditions

    Science.gov (United States)

    Serrano, Paloma; van Loon, Jack J. W. A.; Medina, F. Javier; Herranz, Raúl

    2013-02-01

    Motility and aging in Drosophila have proven to be highly modified under altered gravity conditions (both in space and ground simulation facilities). In order to find out how closely connected they are, five strains with altered geotactic response or survival rates were selected and exposed to an altered gravity environment of 2 g. By analysing the different motile and behavioural patterns and the median survival rates, we show that altered gravity leads to changes in motility, which will have a negative impact on the flies' survival. Previous results show a differential gene expression between sessile samples and adults and confirm that environmentally-conditioned behavioural patterns constrain flies' gene expression and life span. Therefore, hypergravity is considered an environmental stress factor and strains that do not respond to this new environment experience an increment in motility, which is the major cause for the observed increased mortality also under microgravity conditions. The neutral-geotaxis selected strain (strain M) showed the most severe phenotype, unable to respond to variations in the gravitational field. Alternatively, the opposite phenotype was observed in positive-geotaxis and long-life selected flies (strains B and L, respectively), suggesting that these populations are less sensitive to alterations in the gravitational load. We conclude that the behavioural response has a greater contribution to aging than the modified energy consumption in altered gravity environments.

  14. The probability estimate of the defects of the asynchronous motors based on the complex method of diagnostics

    Science.gov (United States)

    Zhukovskiy, Yu L.; Korolev, N. A.; Babanova, I. S.; Boikov, A. V.

    2017-10-01

    This article is devoted to the development of a method for probability estimate of failure of an asynchronous motor as a part of electric drive with a frequency converter. The proposed method is based on a comprehensive method of diagnostics of vibration and electrical characteristics that take into account the quality of the supply network and the operating conditions. The developed diagnostic system allows to increase the accuracy and quality of diagnoses by determining the probability of failure-free operation of the electromechanical equipment, when the parameters deviate from the norm. This system uses an artificial neural networks (ANNs). The results of the system for estimator the technical condition are probability diagrams of the technical state and quantitative evaluation of the defects of the asynchronous motor and its components.

  15. Probability via expectation

    CERN Document Server

    Whittle, Peter

    1992-01-01

    This book is a complete revision of the earlier work Probability which ap­ peared in 1970. While revised so radically and incorporating so much new material as to amount to a new text, it preserves both the aim and the approach of the original. That aim was stated as the provision of a 'first text in probability, de­ manding a reasonable but not extensive knowledge of mathematics, and taking the reader to what one might describe as a good intermediate level'. In doing so it attempted to break away from stereotyped applications, and consider applications of a more novel and significant character. The particular novelty of the approach was that expectation was taken as the prime concept, and the concept of expectation axiomatized rather than that of a probability measure. In the preface to the original text of 1970 (reproduced below, together with that to the Russian edition of 1982) I listed what I saw as the advantages of the approach in as unlaboured a fashion as I could. I also took the view that the text...

  16. The probability outcome correpondence principle : a dispositional view of the interpretation of probability statements

    NARCIS (Netherlands)

    Keren, G.; Teigen, K.H.

    2001-01-01

    This article presents a framework for lay people's internal representations of probabilities, which supposedly reflect the strength of underlying dispositions, or propensities, associated with the predicted event. From this framework, we derive the probability-outcome correspondence principle, which

  17. Ethanol-induced conditioned taste aversion in male sprague-dawley rats: impact of age and stress.

    Science.gov (United States)

    Anderson, Rachel I; Varlinskaya, Elena I; Spear, Linda P

    2010-12-01

    Age-specific characteristics may contribute to the elevation in ethanol intake commonly reported among adolescents compared to adults. This study was designed to examine age-related differences in sensitivity to ethanol's aversive properties using a conditioned taste aversion (CTA) procedure with sucrose serving as the conditioned stimulus (CS). Given that ontogenetic differences in responsiveness to stressors have been previously reported, the role of stressor exposure on the development of CTA was also assessed. Experiment 1 examined the influence of 5 days of prior restraint stress exposure on the expression of CTA in a 2-bottle test following 1 pairing of a sucrose solution with ethanol. In Experiment 2, the effects of 7 days of social isolation on the development of CTA were observed using a 1-bottle test following multiple sucrose-ethanol pairings. This study revealed age-related differences in the development of ethanol-induced CTA. In Experiment 1, adolescents required a higher dose of ethanol than adults to demonstrate an aversion. In Experiment 2, adolescents required not only a higher ethanol dose but also more pairings of ethanol with the sucrose CS. No effects of prior stressor exposure were observed in either experiment. Together, these experiments demonstrate an adolescent-specific insensitivity to the aversive properties of ethanol that elicit CTA, a pattern not influenced by repeated restraint stress or housing in social isolation. This age-related insensitivity to the dysphoric effects of ethanol is consistent with other work from our laboratory, adding further to the evidence that adolescent rats are less susceptible to negative consequences of ethanol that may serve as cues to curb consumption. Copyright © 2010 by the Research Society on Alcoholism.

  18. Poisson Processes in Free Probability

    OpenAIRE

    An, Guimei; Gao, Mingchu

    2015-01-01

    We prove a multidimensional Poisson limit theorem in free probability, and define joint free Poisson distributions in a non-commutative probability space. We define (compound) free Poisson process explicitly, similar to the definitions of (compound) Poisson processes in classical probability. We proved that the sum of finitely many freely independent compound free Poisson processes is a compound free Poisson processes. We give a step by step procedure for constructing a (compound) free Poisso...

  19. Relative ages of lava flows at Alba Patera, Mars

    International Nuclear Information System (INIS)

    Schneeberger, D.M.; Pieri, D.C.

    1987-01-01

    Many large lava flows on the flanks of Alba Patera are astonishing in their volume and length. As a suite, these flows suggest tremendously voluminous and sustained eruptions, and provide dimensional boundary conditions typically a factor of 100 larger than terrestrial flows. One of the most striking features associated with Alba Patera is the large, radially oriented lava flows that exhibit a variety of flow morphologies. These include sheet flows, tube fed and tube channel flows, and undifferentiated flows. Three groups of flows were studied; flows on the northwest flank, southeast flank, and the intracaldera region. The lava flows discussed probably were erupted as a group during the same major volcanic episode as suggested by the data presented. Absolute ages are poorly constrained for both the individual flows and shield, due in part to disagreement as to which absolute age curve is representative for Mars. A relative age sequence is implied but lacks precision due to the closeness of the size frequency curves

  20. Bayesian noninferiority test for 2 binomial probabilities as the extension of Fisher exact test.

    Science.gov (United States)

    Doi, Masaaki; Takahashi, Fumihiro; Kawasaki, Yohei

    2017-12-30

    Noninferiority trials have recently gained importance for the clinical trials of drugs and medical devices. In these trials, most statistical methods have been used from a frequentist perspective, and historical data have been used only for the specification of the noninferiority margin Δ>0. In contrast, Bayesian methods, which have been studied recently are advantageous in that they can use historical data to specify prior distributions and are expected to enable more efficient decision making than frequentist methods by borrowing information from historical trials. In the case of noninferiority trials for response probabilities π 1 ,π 2 , Bayesian methods evaluate the posterior probability of H 1 :π 1 >π 2 -Δ being true. To numerically calculate such posterior probability, complicated Appell hypergeometric function or approximation methods are used. Further, the theoretical relationship between Bayesian and frequentist methods is unclear. In this work, we give the exact expression of the posterior probability of the noninferiority under some mild conditions and propose the Bayesian noninferiority test framework which can flexibly incorporate historical data by using the conditional power prior. Further, we show the relationship between Bayesian posterior probability and the P value of the Fisher exact test. From this relationship, our method can be interpreted as the Bayesian noninferior extension of the Fisher exact test, and we can treat superiority and noninferiority in the same framework. Our method is illustrated through Monte Carlo simulations to evaluate the operating characteristics, the application to the real HIV clinical trial data, and the sample size calculation using historical data. Copyright © 2017 John Wiley & Sons, Ltd.

  1. Sensitivity of the probability of failure to probability of detection curve regions

    International Nuclear Information System (INIS)

    Garza, J.; Millwater, H.

    2016-01-01

    Non-destructive inspection (NDI) techniques have been shown to play a vital role in fracture control plans, structural health monitoring, and ensuring availability and reliability of piping, pressure vessels, mechanical and aerospace equipment. Probabilistic fatigue simulations are often used in order to determine the efficacy of an inspection procedure with the NDI method modeled as a probability of detection (POD) curve. These simulations can be used to determine the most advantageous NDI method for a given application. As an aid to this process, a first order sensitivity method of the probability-of-failure (POF) with respect to regions of the POD curve (lower tail, middle region, right tail) is developed and presented here. The sensitivity method computes the partial derivative of the POF with respect to a change in each region of a POD or multiple POD curves. The sensitivities are computed at no cost by reusing the samples from an existing Monte Carlo (MC) analysis. A numerical example is presented considering single and multiple inspections. - Highlights: • Sensitivities of probability-of-failure to a region of probability-of-detection curve. • The sensitivities are computed with negligible cost. • Sensitivities identify the important region of a POD curve. • Sensitivities can be used as a guide to selecting the optimal POD curve.

  2. Probability of primordial black hole pair creation in a modified gravitational theory

    International Nuclear Information System (INIS)

    Paul, B. C.; Paul, Dilip

    2006-01-01

    We compute the probability for quantum creation of an inflationary universe with and without a pair of black holes in a modified gravity. The action of the modified theory of gravity contains αR 2 and δR -1 terms in addition to a cosmological constant (Λ) in the Einstein-Hilbert action. The probabilities for the creation of universe with a pair of black holes have been evaluated considering two different kinds of spatial sections, one which accommodates a pair of black holes and the other without black hole. We adopt a technique prescribed by Bousso and Hawking to calculate the above creation probability in a semiclassical approximation using the Hartle-Hawking boundary condition. We note a class of new and physically interesting instanton solutions characterized by the parameters in the action. These instantons may play an important role in the creation of the early universe. We also note that the probability of creation of a universe with a pair of black holes is strongly suppressed with a positive cosmological constant when δ=(4Λ 2 /3) for α>0 but it is more probable for α<-(1/6Λ). In the modified gravity considered here instanton solutions are permitted even without a cosmological constant when one begins with a negative δ

  3. Truth, possibility and probability new logical foundations of probability and statistical inference

    CERN Document Server

    Chuaqui, R

    1991-01-01

    Anyone involved in the philosophy of science is naturally drawn into the study of the foundations of probability. Different interpretations of probability, based on competing philosophical ideas, lead to different statistical techniques, and frequently to mutually contradictory consequences. This unique book presents a new interpretation of probability, rooted in the traditional interpretation that was current in the 17th and 18th centuries. Mathematical models are constructed based on this interpretation, and statistical inference and decision theory are applied, including some examples in artificial intelligence, solving the main foundational problems. Nonstandard analysis is extensively developed for the construction of the models and in some of the proofs. Many nonstandard theorems are proved, some of them new, in particular, a representation theorem that asserts that any stochastic process can be approximated by a process defined over a space with equiprobable outcomes.

  4. Effect of environmental conditions and lesion age on sporulation of Phytophthora ramorum on California bay laurel, rhododendron, and camellia

    Science.gov (United States)

    Steve Tjosvold; David Chambers; Sylvia Mori

    2013-01-01

    The objective of our research was to determine the environmental conditions and lesion age favorable for Phytophthora ramorum sporulation under field conditions. For 2 years, new camellia, rhododendron, and California bay laurel (Umbellaria californica (Hook. & Arn.) Nutt.) nursery stock were seasonally inoculated (every 3 months) on foliage....

  5. Pre-Aggregation with Probability Distributions

    DEFF Research Database (Denmark)

    Timko, Igor; Dyreson, Curtis E.; Pedersen, Torben Bach

    2006-01-01

    Motivated by the increasing need to analyze complex, uncertain multidimensional data this paper proposes probabilistic OLAP queries that are computed using probability distributions rather than atomic values. The paper describes how to create probability distributions from base data, and how...... the distributions can be subsequently used in pre-aggregation. Since the probability distributions can become large, we show how to achieve good time and space efficiency by approximating the distributions. We present the results of several experiments that demonstrate the effectiveness of our methods. The work...... is motivated with a real-world case study, based on our collaboration with a leading Danish vendor of location-based services. This paper is the first to consider the approximate processing of probabilistic OLAP queries over probability distributions....

  6. Dynamic probability evaluation of safety levels of earth-rockfill dams using Bayesian approach

    Directory of Open Access Journals (Sweden)

    Zi-wu Fan

    2009-06-01

    Full Text Available In order to accurately predict and control the aging process of dams, new information should be collected continuously to renew the quantitative evaluation of dam safety levels. Owing to the complex structural characteristics of dams, it is quite difficult to predict the time-varying factors affecting their safety levels. It is not feasible to employ dynamic reliability indices to evaluate the actual safety levels of dams. Based on the relevant regulations for dam safety classification in China, a dynamic probability description of dam safety levels was developed. Using the Bayesian approach and effective information mining, as well as real-time information, this study achieved more rational evaluation and prediction of dam safety levels. With the Bayesian expression of discrete stochastic variables, the a priori probabilities of the dam safety levels determined by experts were combined with the likelihood probability of the real-time check information, and the probability information for the evaluation of dam safety levels was renewed. The probability index was then applied to dam rehabilitation decision-making. This method helps reduce the difficulty and uncertainty of the evaluation of dam safety levels and complies with the current safe decision-making regulations for dams in China. It also enhances the application of current risk analysis methods for dam safety levels.

  7. Boy with central precocious puberty probably due to a peripheral cause.

    Science.gov (United States)

    Sahana, Pranab Kumar; Gopal Sankar, Krishna Shankar; Sengupta, Nilanjan; Chattopadhyay, Kaustubh

    2016-06-02

    A 6½ years Indian boy was brought by his parents, who were anxious about the excessive increase in the size of the boy's phallus, from the age of 2 years. On physical examination, the child had a penis length greater than the 97th centile for age, a sexual maturity rating of gonads at stage 2 and pubic hair at stage 3, with height in the high normal range (90-97th centile). The bone age was 12 years. Laboratory evaluation showed pubertal levels of testosterone and pubertal gonadotropin response to stimulation, confirming central precocious puberty (CPP). Incidentally, the hormonal profile also suggested congenital adrenal hyperplasia (CAH). This case report depicts a case of CPP probably caused by CAH in boys, which is rare. 2016 BMJ Publishing Group Ltd.

  8. Transitional Probabilities Are Prioritized over Stimulus/Pattern Probabilities in Auditory Deviance Detection: Memory Basis for Predictive Sound Processing.

    Science.gov (United States)

    Mittag, Maria; Takegata, Rika; Winkler, István

    2016-09-14

    Representations encoding the probabilities of auditory events do not directly support predictive processing. In contrast, information about the probability with which a given sound follows another (transitional probability) allows predictions of upcoming sounds. We tested whether behavioral and cortical auditory deviance detection (the latter indexed by the mismatch negativity event-related potential) relies on probabilities of sound patterns or on transitional probabilities. We presented healthy adult volunteers with three types of rare tone-triplets among frequent standard triplets of high-low-high (H-L-H) or L-H-L pitch structure: proximity deviant (H-H-H/L-L-L), reversal deviant (L-H-L/H-L-H), and first-tone deviant (L-L-H/H-H-L). If deviance detection was based on pattern probability, reversal and first-tone deviants should be detected with similar latency because both differ from the standard at the first pattern position. If deviance detection was based on transitional probabilities, then reversal deviants should be the most difficult to detect because, unlike the other two deviants, they contain no low-probability pitch transitions. The data clearly showed that both behavioral and cortical auditory deviance detection uses transitional probabilities. Thus, the memory traces underlying cortical deviance detection may provide a link between stimulus probability-based change/novelty detectors operating at lower levels of the auditory system and higher auditory cognitive functions that involve predictive processing. Our research presents the first definite evidence for the auditory system prioritizing transitional probabilities over probabilities of individual sensory events. Forming representations for transitional probabilities paves the way for predictions of upcoming sounds. Several recent theories suggest that predictive processing provides the general basis of human perception, including important auditory functions, such as auditory scene analysis. Our

  9. Probability tales

    CERN Document Server

    Grinstead, Charles M; Snell, J Laurie

    2011-01-01

    This book explores four real-world topics through the lens of probability theory. It can be used to supplement a standard text in probability or statistics. Most elementary textbooks present the basic theory and then illustrate the ideas with some neatly packaged examples. Here the authors assume that the reader has seen, or is learning, the basic theory from another book and concentrate in some depth on the following topics: streaks, the stock market, lotteries, and fingerprints. This extended format allows the authors to present multiple approaches to problems and to pursue promising side discussions in ways that would not be possible in a book constrained to cover a fixed set of topics. To keep the main narrative accessible, the authors have placed the more technical mathematical details in appendices. The appendices can be understood by someone who has taken one or two semesters of calculus.

  10. Outage Probability Analysis of FSO Links over Foggy Channel

    KAUST Repository

    Esmail, Maged Abdullah

    2017-02-22

    Outdoor Free space optic (FSO) communication systems are sensitive to atmospheric impairments such as turbulence and fog, in addition to being subject to pointing errors. Fog is particularly severe because it induces an attenuation that may vary from few dBs up to few hundreds of dBs per kilometer. Pointing errors also distort the link alignment and cause signal fading. In this paper, we investigate and analyze the FSO systems performance under fog conditions and pointing errors in terms of outage probability. We then study the impact of several effective communication mitigation techniques that can improve the system performance including multi-hop, transmit laser selection (TLS) and hybrid RF/FSO transmission. Closed-form expressions for the outage probability are derived and practical and comprehensive numerical examples are suggested to assess the obtained results. We found that the FSO system has limited performance that prevents applying FSO in wireless microcells that have a 500 m minimum cell radius. The performance degrades more when pointing errors appear. Increasing the transmitted power can improve the performance under light to moderate fog. However, under thick and dense fog the improvement is negligible. Using mitigation techniques can play a major role in improving the range and outage probability.

  11. Outage Probability Analysis of FSO Links over Foggy Channel

    KAUST Repository

    Esmail, Maged Abdullah; Fathallah, Habib; Alouini, Mohamed-Slim

    2017-01-01

    Outdoor Free space optic (FSO) communication systems are sensitive to atmospheric impairments such as turbulence and fog, in addition to being subject to pointing errors. Fog is particularly severe because it induces an attenuation that may vary from few dBs up to few hundreds of dBs per kilometer. Pointing errors also distort the link alignment and cause signal fading. In this paper, we investigate and analyze the FSO systems performance under fog conditions and pointing errors in terms of outage probability. We then study the impact of several effective communication mitigation techniques that can improve the system performance including multi-hop, transmit laser selection (TLS) and hybrid RF/FSO transmission. Closed-form expressions for the outage probability are derived and practical and comprehensive numerical examples are suggested to assess the obtained results. We found that the FSO system has limited performance that prevents applying FSO in wireless microcells that have a 500 m minimum cell radius. The performance degrades more when pointing errors appear. Increasing the transmitted power can improve the performance under light to moderate fog. However, under thick and dense fog the improvement is negligible. Using mitigation techniques can play a major role in improving the range and outage probability.

  12. A Tale of Two Probabilities

    Science.gov (United States)

    Falk, Ruma; Kendig, Keith

    2013-01-01

    Two contestants debate the notorious probability problem of the sex of the second child. The conclusions boil down to explication of the underlying scenarios and assumptions. Basic principles of probability theory are highlighted.

  13. Probabilistic Inference: Task Dependency and Individual Differences of Probability Weighting Revealed by Hierarchical Bayesian Modeling.

    Science.gov (United States)

    Boos, Moritz; Seer, Caroline; Lange, Florian; Kopp, Bruno

    2016-01-01

    Cognitive determinants of probabilistic inference were examined using hierarchical Bayesian modeling techniques. A classic urn-ball paradigm served as experimental strategy, involving a factorial two (prior probabilities) by two (likelihoods) design. Five computational models of cognitive processes were compared with the observed behavior. Parameter-free Bayesian posterior probabilities and parameter-free base rate neglect provided inadequate models of probabilistic inference. The introduction of distorted subjective probabilities yielded more robust and generalizable results. A general class of (inverted) S-shaped probability weighting functions had been proposed; however, the possibility of large differences in probability distortions not only across experimental conditions, but also across individuals, seems critical for the model's success. It also seems advantageous to consider individual differences in parameters of probability weighting as being sampled from weakly informative prior distributions of individual parameter values. Thus, the results from hierarchical Bayesian modeling converge with previous results in revealing that probability weighting parameters show considerable task dependency and individual differences. Methodologically, this work exemplifies the usefulness of hierarchical Bayesian modeling techniques for cognitive psychology. Theoretically, human probabilistic inference might be best described as the application of individualized strategic policies for Bayesian belief revision.

  14. Probabilistic inference: Task dependency and individual differences of probability weighting revealed by hierarchical Bayesian modelling

    Directory of Open Access Journals (Sweden)

    Moritz eBoos

    2016-05-01

    Full Text Available Cognitive determinants of probabilistic inference were examined using hierarchical Bayesian modelling techniques. A classic urn-ball paradigm served as experimental strategy, involving a factorial two (prior probabilities by two (likelihoods design. Five computational models of cognitive processes were compared with the observed behaviour. Parameter-free Bayesian posterior probabilities and parameter-free base rate neglect provided inadequate models of probabilistic inference. The introduction of distorted subjective probabilities yielded more robust and generalizable results. A general class of (inverted S-shaped probability weighting functions had been proposed; however, the possibility of large differences in probability distortions not only across experimental conditions, but also across individuals, seems critical for the model’s success. It also seems advantageous to consider individual differences in parameters of probability weighting as being sampled from weakly informative prior distributions of individual parameter values. Thus, the results from hierarchical Bayesian modelling converge with previous results in revealing that probability weighting parameters show considerable task dependency and individual differences. Methodologically, this work exemplifies the usefulness of hierarchical Bayesian modelling techniques for cognitive psychology. Theoretically, human probabilistic inference might be best described as the application of individualized strategic policies for Bayesian belief revision.

  15. Aged dominant negative p38α MAPK mice are resistant to age-dependent decline in adult-neurogenesis and context discrimination fear conditioning.

    Science.gov (United States)

    Cortez, IbDanelo; Bulavin, Dmitry V; Wu, Ping; McGrath, Erica L; Cunningham, Kathryn A; Wakamiya, Maki; Papaconstantinou, John; Dineley, Kelly T

    2017-03-30

    A major aspect of mammalian aging is the decline in functional competence of many self-renewing cell types, including adult-born neuronal precursors. Since age-related senescence of self-renewal occurs simultaneously with chronic up-regulation of the p38MAPKalpha (p38α) signaling pathway, we used the dominant negative mouse model for attenuated p38α activity (DN-p38α AF/+ ) in which Thr180 and Tyr182 are mutated (T→A/Y→F) to prevent phosphorylation activation (DN-p38α AF/+ ) and kinase activity. As a result, aged DN-p38α AF/+ mice are resistant to age-dependent decline in proliferation and regeneration of several peripheral tissue progenitors when compared to wild-type littermates. Aging is the major risk factor for non-inherited forms of Alzheimer's disease (AD); environmental and genetic risk factors that accelerate the senescence phenotype are thought to contribute to an individual's relative risk. In the present study, we evaluated aged DN-p38α AF/+ and wildtype littermates in a series of behavioral paradigms to test if p38α mutant mice exhibit altered baseline abnormalities in neurological reflexes, locomotion, anxiety-like behavior, and age-dependent cognitive decline. While aged DN-p38α AF/+ and wildtype littermates appear equal in all tested baseline neurological and behavioral parameters, DN-p38α AF/+ exhibit superior context discrimination fear conditioning. Context discrimination is a cognitive task that is supported by proliferation and differentiation of adult-born neurons in the dentate gyrus of the hippocampus. Consistent with enhanced context discrimination in aged DN-p38α AF/+ , we discovered enhanced production of adult-born neurons in the dentate gyrus of DN-p38α AF/+ mice compared to wildtype littermates. Our findings support the notion that p38α inhibition has therapeutic utility in aging diseases that affect cognition, such as AD. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Impact of controlling the sum of error probability in the sequential probability ratio test

    Directory of Open Access Journals (Sweden)

    Bijoy Kumarr Pradhan

    2013-05-01

    Full Text Available A generalized modified method is proposed to control the sum of error probabilities in sequential probability ratio test to minimize the weighted average of the two average sample numbers under a simple null hypothesis and a simple alternative hypothesis with the restriction that the sum of error probabilities is a pre-assigned constant to find the optimal sample size and finally a comparison is done with the optimal sample size found from fixed sample size procedure. The results are applied to the cases when the random variate follows a normal law as well as Bernoullian law.

  17. A Numerical Model for the Thermomechanical Conditions During Hydration of Early-age Concrete

    DEFF Research Database (Denmark)

    Hattel, Jesper; Thorborg, Jesper

    2003-01-01

    In the present study, a macroscopic numerical model for the thermomechanical conditions during hydration of early-age concrete is presented. The formulation is based on a semi-coupled, incremental thermomechanical model where the heat production from the hydration process is expressed in terms...... of the maturity and the thermal activation is expressed by the Arrhenius principle. The material properties are assumed to depend on the hydration process via the maturity. The discretization of the governing equations is accomplished by a control volume formulation involving a time-splitting scheme for the heat...

  18. Upgrading Probability via Fractions of Events

    Directory of Open Access Journals (Sweden)

    Frič Roman

    2016-08-01

    Full Text Available The influence of “Grundbegriffe” by A. N. Kolmogorov (published in 1933 on education in the area of probability and its impact on research in stochastics cannot be overestimated. We would like to point out three aspects of the classical probability theory “calling for” an upgrade: (i classical random events are black-and-white (Boolean; (ii classical random variables do not model quantum phenomena; (iii basic maps (probability measures and observables { dual maps to random variables have very different “mathematical nature”. Accordingly, we propose an upgraded probability theory based on Łukasiewicz operations (multivalued logic on events, elementary category theory, and covering the classical probability theory as a special case. The upgrade can be compared to replacing calculations with integers by calculations with rational (and real numbers. Namely, to avoid the three objections, we embed the classical (Boolean random events (represented by the f0; 1g-valued indicator functions of sets into upgraded random events (represented by measurable {0; 1}-valued functions, the minimal domain of probability containing “fractions” of classical random events, and we upgrade the notions of probability measure and random variable.

  19. Oral health conditions and frailty in Mexican community-dwelling elderly: a cross sectional analysis

    Directory of Open Access Journals (Sweden)

    Castrejón-Pérez Roberto

    2012-09-01

    Full Text Available Abstract Background Oral health is an important component of general well-being for the elderly. Oral health-related problems include loss of teeth, nonfunctional removable dental prostheses, lesions of the oral mucosa, periodontitis, and root caries. They affect food selection, speaking ability, mastication, social relations, and quality of life. Frailty is a geriatric syndrome that confers vulnerability to negative health-related outcomes. The association between oral health and frailty has not been explored thoroughly. This study sought to identify associations between the presence of some oral health conditions, and frailty status among Mexican community-dwelling elderly. Methods Analysis of baseline data of the Mexican Study of Nutritional and Psychosocial Markers of Frailty, a cohort study carried out in a representative sample of people aged 70 and older residing in one district of Mexico City. Frailty was defined as the presence of three or more of the following five components: weight loss, exhaustion, slowness, weakness, and low physical activity. Oral health variables included self-perception of oral health compared with others of the same age; utilization of dental services during the last year, number of teeth, dental condition (edentate, partially edentate, or completely dentate, utilization and functionality of removable partial or complete dentures, severe periodontitis, self-reported chewing problems and xerostomia. Covariates included were gender, age, years of education, cognitive performance, smoking status, recent falls, hospitalization, number of drugs, and comorbidity. The association between frailty and dental variables was determined performing a multivariate logistic regression analysis. Final models were adjusted by socio-demographic and health factors Results Of the 838 participants examined, 699 had the information needed to establish the criteria for diagnosis of frailty. Those who had a higher probability of being

  20. Earthquake Probability Assessment for the Active Faults in Central Taiwan: A Case Study

    Directory of Open Access Journals (Sweden)

    Yi-Rui Lee

    2016-06-01

    Full Text Available Frequent high seismic activities occur in Taiwan due to fast plate motions. According to the historical records the most destructive earthquakes in Taiwan were caused mainly by inland active faults. The Central Geological Survey (CGS of Taiwan has published active fault maps in Taiwan since 1998. There are 33 active faults noted in the 2012 active fault map. After the Chi-Chi earthquake, CGS launched a series of projects to investigate the details to better understand each active fault in Taiwan. This article collected this data to develop active fault parameters and referred to certain experiences from Japan and the United States to establish a methodology for earthquake probability assessment via active faults. We consider the active faults in Central Taiwan as a good example to present the earthquake probability assessment process and results. The appropriate “probability model” was used to estimate the conditional probability where M ≥ 6.5 and M ≥ 7.0 earthquakes. Our result shows that the highest earthquake probability for M ≥ 6.5 earthquake occurring in 30, 50, and 100 years in Central Taiwan is the Tachia-Changhua fault system. Conversely, the lowest earthquake probability is the Chelungpu fault. The goal of our research is to calculate the earthquake probability of the 33 active faults in Taiwan. The active fault parameters are important information that can be applied in the following seismic hazard analysis and seismic simulation.

  1. A Comprehensive Probability Project for the Upper Division One-Semester Probability Course Using Yahtzee

    Science.gov (United States)

    Wilson, Jason; Lawman, Joshua; Murphy, Rachael; Nelson, Marissa

    2011-01-01

    This article describes a probability project used in an upper division, one-semester probability course with third-semester calculus and linear algebra prerequisites. The student learning outcome focused on developing the skills necessary for approaching project-sized math/stat application problems. These skills include appropriately defining…

  2. The probability of reinforcement per trial affects posttrial responding and subsequent extinction but not within-trial responding.

    Science.gov (United States)

    Harris, Justin A; Kwok, Dorothy W S

    2018-01-01

    During magazine approach conditioning, rats do not discriminate between a conditional stimulus (CS) that is consistently reinforced with food and a CS that is occasionally (partially) reinforced, as long as the CSs have the same overall reinforcement rate per second. This implies that rats are indifferent to the probability of reinforcement per trial. However, in the same rats, the per-trial reinforcement rate will affect subsequent extinction-responding extinguishes more rapidly for a CS that was consistently reinforced than for a partially reinforced CS. Here, we trained rats with consistently and partially reinforced CSs that were matched for overall reinforcement rate per second. We measured conditioned responding both during and immediately after the CSs. Differences in the per-trial probability of reinforcement did not affect the acquisition of responding during the CS but did affect subsequent extinction of that responding, and also affected the post-CS response rates during conditioning. Indeed, CSs with the same probability of reinforcement per trial evoked the same amount of post-CS responding even when they differed in overall reinforcement rate and thus evoked different amounts of responding during the CS. We conclude that reinforcement rate per second controls rats' acquisition of responding during the CS, but at the same time, rats also learn specifically about the probability of reinforcement per trial. The latter learning affects the rats' expectation of reinforcement as an outcome of the trial, which influences their ability to detect retrospectively that an opportunity for reinforcement was missed, and, in turn, drives extinction. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  3. Dynamics of atom-field probability amplitudes in a coupled cavity system with Kerr non-linearity

    Energy Technology Data Exchange (ETDEWEB)

    Priyesh, K. V.; Thayyullathil, Ramesh Babu [Department of Physics, Cochin University of Science and Technology, Cochin (India)

    2014-01-28

    We have investigated the dynamics of two cavities coupled together via photon hopping, filled with Kerr non-linear medium and each containing a two level atom in it. The evolution of various atom (field) state probabilities of the coupled cavity system in two excitation sub space are obtained numerically. Detailed analysis has been done by taking different initial conditions of the system, with various coupling strengths and by varying the susceptibility of the medium. The role of susceptibility factor, on the dynamics atom field probability has been examined. In a coupled cavity system with strong photon hopping it is found that the susceptibility factor modifies the behaviour of probability amplitudes.

  4. Passage and survival probabilities of juvenile Chinook salmon at Cougar Dam, Oregon, 2012

    Science.gov (United States)

    Beeman, John W.; Evans, Scott D.; Haner, Philip V.; Hansel, Hal C.; Hansen, Amy C.; Smith, Collin D.; Sprando, Jamie M.

    2014-01-01

    This report describes studies of juvenile-salmon dam passage and apparent survival at Cougar Dam, Oregon, during two operating conditions in 2012. Cougar Dam is a 158-meter tall rock-fill dam used primarily for flood control, and passes water through a temperature control tower to either a powerhouse penstock or to a regulating outlet (RO). The temperature control tower has moveable weir gates to enable water of different elevations and temperatures to be drawn through the dam to control water temperatures downstream. A series of studies of downstream dam passage of juvenile salmonids were begun after the National Oceanic and Atmospheric Administration determined that Cougar Dam was impacting the viability of anadromous fish stocks. The primary objectives of the studies described in this report were to estimate the route-specific fish passage probabilities at the dam and to estimate the survival probabilities of fish passing through the RO. The first set of dam operating conditions, studied in November, consisted of (1) a mean reservoir elevation of 1,589 feet, (2) water entering the temperature control tower through the weir gates, (3) most water routed through the turbines during the day and through the RO during the night, and (4) mean RO gate openings of 1.2 feet during the day and 3.2 feet during the night. The second set of dam operating conditions, studied in December, consisted of (1) a mean reservoir elevation of 1,507 ft, (2) water entering the temperature control tower through the RO bypass, (3) all water passing through the RO, and (4) mean RO gate openings of 7.3 feet during the day and 7.5 feet during the night. The studies were based on juvenile Chinook salmon (Oncorhynchus tshawytscha) surgically implanted with radio transmitters and passive integrated transponder (PIT) tags. Inferences about general dam passage percentage and timing of volitional migrants were based on surface-acclimated fish released in the reservoir. Dam passage and apparent

  5. Description age-3 brood rainbow trout bred in the conditions of the industral fish farm "Sloboda Banyliv"

    Directory of Open Access Journals (Sweden)

    P. Mendryshora

    2017-06-01

    Full Text Available Purpose. To analyze the results of cultivation and give fish-breeding and biological characteristics of age-3 brood rainbow trout grown using industrial technology in the conditions of the trout farm "Sloboda Banyliv." Methodology. Fish cultivation was carried in tank conditions of the trout farm "Sloboda Banyliv". The material for the study were age-3 brood rainbow trout obtained from eggs of the fall-spawning form of rainbow trout. Cultivation was carried out in a 216 m2 tank, stocking density of 255 fish/m2, using standard trout culture methods. Statistical analysis of the material was performed in Microsoft Office Excel (2003. Analysis of the variables was performed in the system of absolute values. The analysis criteria were their mean values mean deviations (M±m, standard error (σ, variability coefficient (Cv. Fish were fed with specialized feed manufactured by “BioMar” (Denmark with a high protein content (more than 40%. Findings. Based on the performed selective-breeding works aimed at creating brood stocks of rainbow trout, it was found that brood fish reared in the industrial conditions of the fish farm “Sloboda Banyliv”, despite instable culture conditions, were characterized by a moderate growth rate and had high values of productive and reproductive features. Mean weight of age-3 rainbow trout females was 1282.5 g, fecundity — 3.48 thousand eggs. Mean weight of produced eggs was 239.17 g, while individual parameters were 70.4 mg for the weight and 4.58 mm for the diameter. Originality. For the first time a study aimed at the formation of brood stocks of rainbow trout with analysis of phenotypic and productive features in the conditions of a fish farm with instable temperature and water regimes has been conducted. Practical value. The results of the performed work will allow selecting and forming a brood stock with high values of productive and reproductive features.

  6. Feedback Valence Affects Auditory Perceptual Learning Independently of Feedback Probability

    Science.gov (United States)

    Amitay, Sygal; Moore, David R.; Molloy, Katharine; Halliday, Lorna F.

    2015-01-01

    Previous studies have suggested that negative feedback is more effective in driving learning than positive feedback. We investigated the effect on learning of providing varying amounts of negative and positive feedback while listeners attempted to discriminate between three identical tones; an impossible task that nevertheless produces robust learning. Four feedback conditions were compared during training: 90% positive feedback or 10% negative feedback informed the participants that they were doing equally well, while 10% positive or 90% negative feedback informed them they were doing equally badly. In all conditions the feedback was random in relation to the listeners’ responses (because the task was to discriminate three identical tones), yet both the valence (negative vs. positive) and the probability of feedback (10% vs. 90%) affected learning. Feedback that informed listeners they were doing badly resulted in better post-training performance than feedback that informed them they were doing well, independent of valence. In addition, positive feedback during training resulted in better post-training performance than negative feedback, but only positive feedback indicating listeners were doing badly on the task resulted in learning. As we have previously speculated, feedback that better reflected the difficulty of the task was more effective in driving learning than feedback that suggested performance was better than it should have been given perceived task difficulty. But contrary to expectations, positive feedback was more effective than negative feedback in driving learning. Feedback thus had two separable effects on learning: feedback valence affected motivation on a subjectively difficult task, and learning occurred only when feedback probability reflected the subjective difficulty. To optimize learning, training programs need to take into consideration both feedback valence and probability. PMID:25946173

  7. Is probability of frequency too narrow?

    International Nuclear Information System (INIS)

    Martz, H.F.

    1993-01-01

    Modern methods of statistical data analysis, such as empirical and hierarchical Bayesian methods, should find increasing use in future Probabilistic Risk Assessment (PRA) applications. In addition, there will be a more formalized use of expert judgment in future PRAs. These methods require an extension of the probabilistic framework of PRA, in particular, the popular notion of probability of frequency, to consideration of frequency of frequency, frequency of probability, and probability of probability. The genesis, interpretation, and examples of these three extended notions are discussed

  8. Effects of the aging temperature and stress relaxation conditions on γ′ precipitation in Inconel X-750

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Jeong Won [Department of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Research and Development Center, KOS Limited, Yangsan 626-230 (Korea, Republic of); Seong, Baek Seok [Neutron Science Division, HANARO Center, Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Jeong, Hi Won [Advanced Metallic Materials Division, Korea Institute of Materials Science, Changwon 642-831 (Korea, Republic of); Choi, Yoon Suk [Department of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of); Kang, Namhyun, E-mail: nhkang@pusan.ac.kr [Department of Materials Science and Engineering, Pusan National University, Busan 609-735 (Korea, Republic of)

    2015-02-15

    Highlights: • Stress relaxation after aging 620 °C increased carbides and maintained γ′ fraction. • Aging temperature increase to 732 °C raised the γ′ increment after stress relaxation. • Small increase of carbides induced the large increase of γ′ after stress relaxation. • Loading for stress relaxation raised γ′ increment due to dislocation multiplication. - Abstract: Inconel X-750 is a Ni-based precipitation-hardened superalloy typically used in springs designed for high-temperature applications such as the hold-down springs in nuclear power plants. γ′ is a major precipitate in X-750 alloys which affects the strength, creep resistance, and stress relaxation properties of the spring. In this study, a solution-treated X-750 wire coiled into a spring was used that was aged at various temperatures and submitted to stress relaxation tests with and without loading. Small angle neutron scattering was employed to quantify the size and volume fraction of γ′ phase in the springs as a function of the aging temperature and the application of a load during stress relaxation. The volume fraction of γ′ precipitates increased in the specimen aged at 732 °C following stress relaxation at 500 °C for 300 h. However, the mean size of the precipitates in the samples was not affected by stress relaxation. The specimen aged at the lower temperature (620 °C) contained a smaller γ′ volume fraction and gained a smaller fraction of γ′ during stress relaxation compared with the sample aged at the higher temperature (732 °C). The smaller increase in the γ′ volume fraction for the sample aged at 620 °C was associated with a larger increase in the M{sub 23}C{sub 6} secondary carbide content during relaxation. The Cr depletion zone around the secondary carbides raises the solubility of γ′ thereby decreasing the volume fraction of γ′ precipitates in Inconel X-750. In terms of stress relaxation, a larger increase in the γ′ volume fraction was

  9. Automatic age and gaze estimation under uncontrolled conditions

    NARCIS (Netherlands)

    Alnajar, F.

    2016-01-01

    Can the computer learn a person’s age just from analyzing facial images obtained by a simple webcam? If so, you can automatically determine if a person has the right age to buy beer (shops), to use a credit card (retail), and can enter bars (entertainment). Can the computer automatically recognize

  10. Particle-bound reactive oxygen species (PB-ROS) emissions and formation pathways in residential wood smoke under different combustion and aging conditions

    Science.gov (United States)

    Zhou, Jun; Zotter, Peter; Bruns, Emily A.; Stefenelli, Giulia; Bhattu, Deepika; Brown, Samuel; Bertrand, Amelie; Marchand, Nicolas; Lamkaddam, Houssni; Slowik, Jay G.; Prévôt, André S. H.; Baltensperger, Urs; Nussbaumer, Thomas; El-Haddad, Imad; Dommen, Josef

    2018-05-01

    Wood combustion emissions can induce oxidative stress in the human respiratory tract by reactive oxygen species (ROS) in the aerosol particles, which are emitted either directly or formed through oxidation in the atmosphere. To improve our understanding of the particle-bound ROS (PB-ROS) generation potential of wood combustion emissions, a suite of smog chamber (SC) and potential aerosol mass (PAM) chamber experiments were conducted under well-determined conditions for different combustion devices and technologies, different fuel types, operation methods, combustion regimes, combustion phases, and aging conditions. The PB-ROS content and the chemical properties of the aerosols were quantified by a novel ROS analyzer using the DCFH (2',7'-dichlorofluorescin) assay and a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS). For all eight combustion devices tested, primary PB-ROS concentrations substantially increased upon aging. The level of primary and aged PB-ROS emission factors (EFROS) were dominated by the combustion device (within different combustion technologies) and to a greater extent by the combustion regimes: the variability within one device was much higher than the variability of EFROS from different devices. Aged EFROS under bad combustion conditions were ˜ 2-80 times higher than under optimum combustion conditions. EFROS from automatically operated combustion devices were on average 1 order of magnitude lower than those from manually operated devices, which indicates that automatic combustion devices operated at optimum conditions to achieve near-complete combustion should be employed to minimize PB-ROS emissions. The use of an electrostatic precipitator decreased the primary and aged ROS emissions by a factor of ˜ 1.5 which is however still within the burn-to-burn variability. The parameters controlling the PB-ROS formation in secondary organic aerosol were investigated by employing a regression model, including the fractions of

  11. Normal probability plots with confidence.

    Science.gov (United States)

    Chantarangsi, Wanpen; Liu, Wei; Bretz, Frank; Kiatsupaibul, Seksan; Hayter, Anthony J; Wan, Fang

    2015-01-01

    Normal probability plots are widely used as a statistical tool for assessing whether an observed simple random sample is drawn from a normally distributed population. The users, however, have to judge subjectively, if no objective rule is provided, whether the plotted points fall close to a straight line. In this paper, we focus on how a normal probability plot can be augmented by intervals for all the points so that, if the population distribution is normal, then all the points should fall into the corresponding intervals simultaneously with probability 1-α. These simultaneous 1-α probability intervals provide therefore an objective mean to judge whether the plotted points fall close to the straight line: the plotted points fall close to the straight line if and only if all the points fall into the corresponding intervals. The powers of several normal probability plot based (graphical) tests and the most popular nongraphical Anderson-Darling and Shapiro-Wilk tests are compared by simulation. Based on this comparison, recommendations are given in Section 3 on which graphical tests should be used in what circumstances. An example is provided to illustrate the methods. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Free probability and random matrices

    CERN Document Server

    Mingo, James A

    2017-01-01

    This volume opens the world of free probability to a wide variety of readers. From its roots in the theory of operator algebras, free probability has intertwined with non-crossing partitions, random matrices, applications in wireless communications, representation theory of large groups, quantum groups, the invariant subspace problem, large deviations, subfactors, and beyond. This book puts a special emphasis on the relation of free probability to random matrices, but also touches upon the operator algebraic, combinatorial, and analytic aspects of the theory. The book serves as a combination textbook/research monograph, with self-contained chapters, exercises scattered throughout the text, and coverage of important ongoing progress of the theory. It will appeal to graduate students and all mathematicians interested in random matrices and free probability from the point of view of operator algebras, combinatorics, analytic functions, or applications in engineering and statistical physics.

  13. Comparision of the different probability distributions for earthquake hazard assessment in the North Anatolian Fault Zone

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Şeyda, E-mail: seydayilmaz@ktu.edu.tr; Bayrak, Erdem, E-mail: erdmbyrk@gmail.com [Karadeniz Technical University, Trabzon (Turkey); Bayrak, Yusuf, E-mail: bayrak@ktu.edu.tr [Ağrı İbrahim Çeçen University, Ağrı (Turkey)

    2016-04-18

    In this study we examined and compared the three different probabilistic distribution methods for determining the best suitable model in probabilistic assessment of earthquake hazards. We analyzed a reliable homogeneous earthquake catalogue between a time period 1900-2015 for magnitude M ≥ 6.0 and estimated the probabilistic seismic hazard in the North Anatolian Fault zone (39°-41° N 30°-40° E) using three distribution methods namely Weibull distribution, Frechet distribution and three-parameter Weibull distribution. The distribution parameters suitability was evaluated Kolmogorov-Smirnov (K-S) goodness-of-fit test. We also compared the estimated cumulative probability and the conditional probabilities of occurrence of earthquakes for different elapsed time using these three distribution methods. We used Easyfit and Matlab software to calculate these distribution parameters and plotted the conditional probability curves. We concluded that the Weibull distribution method was the most suitable than other distribution methods in this region.

  14. Probability with applications and R

    CERN Document Server

    Dobrow, Robert P

    2013-01-01

    An introduction to probability at the undergraduate level Chance and randomness are encountered on a daily basis. Authored by a highly qualified professor in the field, Probability: With Applications and R delves into the theories and applications essential to obtaining a thorough understanding of probability. With real-life examples and thoughtful exercises from fields as diverse as biology, computer science, cryptology, ecology, public health, and sports, the book is accessible for a variety of readers. The book's emphasis on simulation through the use of the popular R software language c

  15. A philosophical essay on probabilities

    CERN Document Server

    Laplace, Marquis de

    1996-01-01

    A classic of science, this famous essay by ""the Newton of France"" introduces lay readers to the concepts and uses of probability theory. It is of especial interest today as an application of mathematical techniques to problems in social and biological sciences.Generally recognized as the founder of the modern phase of probability theory, Laplace here applies the principles and general results of his theory ""to the most important questions of life, which are, in effect, for the most part, problems in probability."" Thus, without the use of higher mathematics, he demonstrates the application

  16. Aging assessment of essential HVAC chillers used in nuclear power plants

    International Nuclear Information System (INIS)

    Blahnik, D.E.; Camp, T.W.

    1996-09-01

    The Pacific Northwest Laboratory conducted a comprehensive aging assessment of chillers used in the essential safety air-conditioning systems in nuclear power plants (NPPs). The chillers used, and air-conditioning systems served, vary in design from plant to plant. The review of operating experience indicated that chillers experience aging degradation and failures. The primary aging factors of concern for chillers include vibration, excessive temperatures and pressures, thermal cycling, chemical attack, and poor quality cooling water. The evaluation of Licensee Event Reports (LERs) indicated that about 38% of the failures were primarily related to aging, 55% were partially aging related, and 7% of the failures were unassignable. About 25% of the failures were primarily caused by human, design, procedure, and other errors. The large number of errors is probably directly related to the complexity of chillers and their interfacing systems. Nearly all of the LERs were the result of entering plant Technical Specification Limiting Condition for Operation (LCO) that initiated remedial actions like plant shutdown procedures. The trend for chiller-related LERs has stabilized at about 0.13 LERs per plant year since 1988. Carefully following the vendor procedures and monitoring the equipment can help to minimize and/or eliminate most of the premature failures. Recording equipment performance can be useful for trending analysis. Periodic operation for a few hours on a weekly or monthly basis is useful to remove moisture and non-condensable gases that gradually build up inside the chiller. Chiller pressurization kits are available that will help minimize the amount of moisture and air ingress to low-pressure chillers during standby periods. The assessment of service life condition monitoring of chillers indicated there are many simple to sophisticated methods available that can help in chiller surveillance and monitoring

  17. Aging assessment of essential HVAC chillers used in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Blahnik, D.E.; Camp, T.W.

    1996-09-01

    The Pacific Northwest Laboratory conducted a comprehensive aging assessment of chillers used in the essential safety air-conditioning systems in nuclear power plants (NPPs). The chillers used, and air-conditioning systems served, vary in design from plant to plant. The review of operating experience indicated that chillers experience aging degradation and failures. The primary aging factors of concern for chillers include vibration, excessive temperatures and pressures, thermal cycling, chemical attack, and poor quality cooling water. The evaluation of Licensee Event Reports (LERs) indicated that about 38% of the failures were primarily related to aging, 55% were partially aging related, and 7% of the failures were unassignable. About 25% of the failures were primarily caused by human, design, procedure, and other errors. The large number of errors is probably directly related to the complexity of chillers and their interfacing systems. Nearly all of the LERs were the result of entering plant Technical Specification Limiting Condition for Operation (LCO) that initiated remedial actions like plant shutdown procedures. The trend for chiller-related LERs has stabilized at about 0.13 LERs per plant year since 1988. Carefully following the vendor procedures and monitoring the equipment can help to minimize and/or eliminate most of the premature failures. Recording equipment performance can be useful for trending analysis. Periodic operation for a few hours on a weekly or monthly basis is useful to remove moisture and non-condensable gases that gradually build up inside the chiller. Chiller pressurization kits are available that will help minimize the amount of moisture and air ingress to low-pressure chillers during standby periods. The assessment of service life condition monitoring of chillers indicated there are many simple to sophisticated methods available that can help in chiller surveillance and monitoring.

  18. A prototype method for diagnosing high ice water content probability using satellite imager data

    Science.gov (United States)

    Yost, Christopher R.; Bedka, Kristopher M.; Minnis, Patrick; Nguyen, Louis; Strapp, J. Walter; Palikonda, Rabindra; Khlopenkov, Konstantin; Spangenberg, Douglas; Smith, William L., Jr.; Protat, Alain; Delanoe, Julien

    2018-03-01

    Recent studies have found that ingestion of high mass concentrations of ice particles in regions of deep convective storms, with radar reflectivity considered safe for aircraft penetration, can adversely impact aircraft engine performance. Previous aviation industry studies have used the term high ice water content (HIWC) to define such conditions. Three airborne field campaigns were conducted in 2014 and 2015 to better understand how HIWC is distributed in deep convection, both as a function of altitude and proximity to convective updraft regions, and to facilitate development of new methods for detecting HIWC conditions, in addition to many other research and regulatory goals. This paper describes a prototype method for detecting HIWC conditions using geostationary (GEO) satellite imager data coupled with in situ total water content (TWC) observations collected during the flight campaigns. Three satellite-derived parameters were determined to be most useful for determining HIWC probability: (1) the horizontal proximity of the aircraft to the nearest overshooting convective updraft or textured anvil cloud, (2) tropopause-relative infrared brightness temperature, and (3) daytime-only cloud optical depth. Statistical fits between collocated TWC and GEO satellite parameters were used to determine the membership functions for the fuzzy logic derivation of HIWC probability. The products were demonstrated using data from several campaign flights and validated using a subset of the satellite-aircraft collocation database. The daytime HIWC probability was found to agree quite well with TWC time trends and identified extreme TWC events with high probability. Discrimination of HIWC was more challenging at night with IR-only information. The products show the greatest capability for discriminating TWC ≥ 0.5 g m-3. Product validation remains challenging due to vertical TWC uncertainties and the typically coarse spatio-temporal resolution of the GEO data.

  19. Monte Carlo simulation of the sequential probability ratio test for radiation monitoring

    International Nuclear Information System (INIS)

    Coop, K.L.

    1984-01-01

    A computer program simulates the Sequential Probability Ratio Test (SPRT) using Monte Carlo techniques. The program, SEQTEST, performs random-number sampling of either a Poisson or normal distribution to simulate radiation monitoring data. The results are in terms of the detection probabilities and the average time required for a trial. The computed SPRT results can be compared with tabulated single interval test (SIT) values to determine the better statistical test for particular monitoring applications. Use of the SPRT in a hand-and-foot alpha monitor shows that the SPRT provides better detection probabilities while generally requiring less counting time. Calculations are also performed for a monitor where the SPRT is not permitted to the take longer than the single interval test. Although the performance of the SPRT is degraded by this restriction, the detection probabilities are still similar to the SIT values, and average counting times are always less than 75% of the SIT time. Some optimal conditions for use of the SPRT are described. The SPRT should be the test of choice in many radiation monitoring situations. 6 references, 8 figures, 1 table

  20. Off-critical local height probabilities on a plane and critical partition functions on a cylinder

    Directory of Open Access Journals (Sweden)

    Omar Foda

    2018-03-01

    Full Text Available We compute off-critical local height probabilities in regime-III restricted solid-on-solid models in a 4N-quadrant spiral geometry, with periodic boundary conditions in the angular direction, and fixed boundary conditions in the radial direction, as a function of N, the winding number of the spiral, and τ, the departure from criticality of the model, and observe that the result depends only on the product Nτ. In the limit N→1, τ→τ0, such that τ0 is finite, we recover the off-critical local height probability on a plane, τ0-away from criticality. In the limit N→∞, τ→0, such that Nτ=τ0 is finite, and following a conformal transformation, we obtain a critical partition function on a cylinder of aspect-ratio τ0. We conclude that the off-critical local height probability on a plane, τ0-away from criticality, is equal to a critical partition function on a cylinder of aspect-ratio τ0, in agreement with a result of Saleur and Bauer.