WorldWideScience

Sample records for susceptibility remains uncertain

  1. Clinical Isolates of Aspergillus Species Remain Fully Susceptible to Voriconazole in the Post-Voriconazole Era▿

    OpenAIRE

    Guinea, Jesús; Recio, Sandra; Peláez, Teresa; Torres-Narbona, Marta; Bouza, Emilio

    2008-01-01

    We studied the activity of voriconazole against 400 clinical strains of Aspergillus from the pre-voriconazole (1999 to 2002) and post-voriconazole (2003 to 2007) periods. Although the mean MICs of strains from the post-voriconazole period were slightly higher (0.39 versus 0.57 μg/ml; P < 0.001), all strains were susceptible to voriconazole and presented an MIC of ≤2 μg/ml.

  2. Cognitive bias in forensic anthropology: visual assessment of skeletal remains is susceptible to confirmation bias.

    Science.gov (United States)

    Nakhaeizadeh, Sherry; Dror, Itiel E; Morgan, Ruth M

    2014-05-01

    An experimental study was designed to examine cognitive biases within forensic anthropological non-metric methods in assessing sex, ancestry and age at death. To investigate examiner interpretation, forty-one non-novice participants were semi randomly divided into three groups. Prior to conducting the assessment of the skeletal remains, two of the groups were given different extraneous contextual information regarding the sex, ancestry and age at death of the individual. The third group acted as a control group with no extraneous contextual information. The experiment was designed to investigate if the interpretation and conclusions of the skeletal remains would differ amongst participants within the three groups, and to assess whether the examiners would confirm or disagree with the given extraneous context when establishing a biological profile. The results revealed a significant biasing effect within the three groups, demonstrating a strong confirmation bias in the assessment of sex, ancestry and age at death. In assessment of sex, 31% of the participants in the control group concluded that the skeleton remains were male. In contrast, in the group that received contextual information that the remains were male, 72% concluded that the remains were male, and in the participant group where the context was that the remains were of a female, 0% of the participants concluded that the remains were male. Comparable results showing bias were found in assessing ancestry and age at death. These data demonstrate that cognitive bias can impact forensic anthropological non-metric methods on skeletal remains and affects the interpretation and conclusions of the forensic scientists. This empirical study is a step in establishing an evidence base approach for dealing with cognitive issues in forensic anthropological assessments, so as to enhance this valuable forensic science discipline. Copyright © 2013 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights

  3. Uncertain Science… Uncertain World

    Science.gov (United States)

    Lempert, Robert

    Why doesn't society act in the face of overwhelming evidence that human influences are changing the Earth's climate? Henry Pollack devotes his book, Uncertain Science… Uncertain World, to addressing one important reason. Much about climate science is highly uncertain, he argues; and as a general rule, most well-educated citizens don't understand the nature of scientific uncertainty. Thus, they have difficulty understanding competing claims made by advocates in the policy debate and in internalizing the extent of the problem.A distinguished professor of geophysics at the University of Michigan, as well as a participant in many public debates involving science, Pollack aims to help lay readers understand the role of uncertainty in science. “In making comparisons and analogies with uncertainties that exist in science and everyday life,” he writes, “my goal is to help readers to understand and accommodate scientific uncertainties in much the same way that they deal with other uncertainties in life.”

  4. Structural Basis of Why Nelfinavir-Resistant D30N Mutant of HIV-1 Protease Remains Susceptible to Saquinavir.

    Science.gov (United States)

    Prashar, Vishal; Bihani, Subhash C; Ferrer, Jean-Luc; Hosur, Madhusoodan V

    2015-09-01

    Although anti-HIV-1 protease drugs nelfinavir (NFV) and saquinavir (SQV) share common functional groups, D30N is a major resistance mutation against NFV but remains susceptible to SQV. We have determined the crystal structure of D30N mutant-tethered HIV-1 protease in complex with SQV to 1.79 Å resolution. Structural analysis showed that SQV forms two direct hydrogen bonds with the main chain atoms of the residues Asp29 and Asp30 that are not observed in the D30N-NFV complex. Apart from maintaining these two main chain hydrogen bonds, the P2-asparagine of SQV forms an additional hydrogen bond to the mutated side chain of the residue 30. These could be the reasons why D30N is not a drug resistance mutation against SQV. This structure supports the previous studies showing that the interactions between a potential inhibitor and backbone atoms of the enzyme are important to maintain potency against drug-resistant HIV-1 protease. © 2014 John Wiley & Sons A/S.

  5. Uncertain Times.

    Science.gov (United States)

    Powell, Suzanne K

    Our health care environment is more uncertain than ever. Uncertainty may lead to stress, burnout, disengagement, or worse. This Editorial discusses causes and potential attitudes to mitigate those feelings, making for a more satisfied employee and more effective patient care.

  6. A Large Proportion of the Mexican Population Remained Susceptible to A(H1N1pdm09 Infection One Year after the Emergence of 2009 Influenza Pandemic.

    Directory of Open Access Journals (Sweden)

    Vic Veguilla

    Full Text Available The 2009 H1N1 influenza pandemic initially affected Mexico from April 2009 to July 2010. By August 2010, a fourth of the population had received the monovalent vaccine against the pandemic virus (A(H1N1pdm09. To assess the proportion of the Mexican population who remained potentially susceptible to infection throughout the summer of 2010, we estimated the population seroprevalence to A(H1N1pdm09 in a serosurvey of blood donors.We evaluated baseline cross-reactivity to the pandemic strain and set the threshold for seropositivity using pre-pandemic (2005-2008 stored serum samples and sera from confirmed A(H1N1pdm09 infected individuals. Between June and September 2010, a convenience sample serosurvey of adult blood donors, children, and adolescents was conducted in six states of Mexico. Sera were tested by the microneutralization (MN and hemagglutination inhibition (HI assays, and regarded seropositive if antibody titers were equal or exceeded 1:40 for MN and 1:20 for HI. Age-standardized seroprevalence were calculated using the 2010 National Census population.Sera from 1,484 individuals were analyzed; 1,363 (92% were blood donors, and 121 (8% children or adolescents aged ≤19 years. Mean age (standard deviation was 31.4 (11.5 years, and 276 (19% were women. A total of 516 (35% participants declared history of influenza vaccination after April 2009. The age-standardized seroprevalence to A(H1N1pdm09 was 48% by the MN and 41% by the HI assays, respectively. The youngest quintile, aged 1 to 22 years, had the highest the seroprevalence; 61% (95% confidence interval [CI]: 56, 66% for MN, and 56% (95% CI: 51, 62% for HI.Despite high transmission of A(H1N1pdm09 observed immediately after its emergence and extensive vaccination, over a half of the Mexican population remained potentially susceptible to A(H1N1pdm09 infection. Subsequent influenza seasons with high transmission of A(H1N1pdm09, as 2011-2012 and 2013-2014, are compatible with these findings.

  7. A Large Proportion of the Mexican Population Remained Susceptible to A(H1N1)pdm09 Infection One Year after the Emergence of 2009 Influenza Pandemic

    Science.gov (United States)

    Veguilla, Vic; López-Gatell, Hugo; López-Martínez, Irma; Aparicio-Antonio, Rodrigo; Barrera-Badillo, Gisela; Rojo-Medina, Julieta; Gross, Felicia Liaini; Jefferson, Stacie N.; Katz, Jacqueline M.; Hernández-Ávila, Mauricio; Alpuche-Aranda, Celia M.

    2016-01-01

    Background The 2009 H1N1 influenza pandemic initially affected Mexico from April 2009 to July 2010. By August 2010, a fourth of the population had received the monovalent vaccine against the pandemic virus (A(H1N1)pdm09). To assess the proportion of the Mexican population who remained potentially susceptible to infection throughout the summer of 2010, we estimated the population seroprevalence to A(H1N1)pdm09 in a serosurvey of blood donors. Methods We evaluated baseline cross-reactivity to the pandemic strain and set the threshold for seropositivity using pre-pandemic (2005–2008) stored serum samples and sera from confirmed A(H1N1)pdm09 infected individuals. Between June and September 2010, a convenience sample serosurvey of adult blood donors, children, and adolescents was conducted in six states of Mexico. Sera were tested by the microneutralization (MN) and hemagglutination inhibition (HI) assays, and regarded seropositive if antibody titers were equal or exceeded 1:40 for MN and 1:20 for HI. Age-standardized seroprevalence were calculated using the 2010 National Census population. Results Sera from 1,484 individuals were analyzed; 1,363 (92%) were blood donors, and 121 (8%) children or adolescents aged ≤19 years. Mean age (standard deviation) was 31.4 (11.5) years, and 276 (19%) were women. A total of 516 (35%) participants declared history of influenza vaccination after April 2009. The age-standardized seroprevalence to A(H1N1)pdm09 was 48% by the MN and 41% by the HI assays, respectively. The youngest quintile, aged 1 to 22 years, had the highest the seroprevalence; 61% (95% confidence interval [CI]: 56, 66%) for MN, and 56% (95% CI: 51, 62%) for HI. Conclusions Despite high transmission of A(H1N1)pdm09 observed immediately after its emergence and extensive vaccination, over a half of the Mexican population remained potentially susceptible to A(H1N1)pdm09 infection. Subsequent influenza seasons with high transmission of A(H1N1)pdm09, as 2011–2012 and

  8. Uncertain differential equations

    CERN Document Server

    Yao, Kai

    2016-01-01

    This book introduces readers to the basic concepts of and latest findings in the area of differential equations with uncertain factors. It covers the analytic method and numerical method for solving uncertain differential equations, as well as their applications in the field of finance. Furthermore, the book provides a number of new potential research directions for uncertain differential equation. It will be of interest to researchers, engineers and students in the fields of mathematics, information science, operations research, industrial engineering, computer science, artificial intelligence, automation, economics, and management science.

  9. Uncertain data envelopment analysis

    CERN Document Server

    Wen, Meilin

    2014-01-01

    This book is intended to present the milestones in the progression of uncertain Data envelopment analysis (DEA). Chapter 1 gives some basic introduction to uncertain theories, including probability theory, credibility theory, uncertainty theory and chance theory. Chapter 2 presents a comprehensive review and discussion of basic DEA models. The stochastic DEA is introduced in Chapter 3, in which the inputs and outputs are assumed to be random variables. To obtain the probability distribution of a random variable, a lot of samples are needed to apply the statistics inference approach. Chapter 4

  10. (Approximate) Uncertain Skylines

    DEFF Research Database (Denmark)

    Afshani, Peyman; Agarwal, Pankaj K.; Arge, Lars Allan

    2011-01-01

    Given a set of points with uncertain locations, we consider the problem of computing the probability of each point lying on the skyline, that is, the probability that it is not dominated by any other input point. If each point’s uncertainty is described as a probability distribution over a discre...... be adapted to construct data structures that can eciently determine the probability of a query point lying on the skyline....

  11. How Uncertain is Uncertainty?

    Science.gov (United States)

    Vámos, Tibor

    The gist of the paper is the fundamental uncertain nature of all kinds of uncertainties and consequently a critical epistemic review of historical and recent approaches, computational methods, algorithms. The review follows the development of the notion from the beginnings of thinking, via the Aristotelian and Skeptic view, the medieval nominalism and the influential pioneering metaphors of ancient India and Persia to the birth of modern mathematical disciplinary reasoning. Discussing the models of uncertainty, e.g. the statistical, other physical and psychological background we reach a pragmatic model related estimation perspective, a balanced application orientation for different problem areas. Data mining, game theories and recent advances in approximation algorithms are discussed in this spirit of modest reasoning.

  12. Visualization of Uncertain Contour Trees

    DEFF Research Database (Denmark)

    Kraus, Martin

    2010-01-01

    Contour trees can represent the topology of large volume data sets in a relatively compact, discrete data structure. However, the resulting trees often contain many thousands of nodes; thus, many graph drawing techniques fail to produce satisfactory results. Therefore, several visualization methods...... were proposed recently for the visualization of contour trees. Unfortunately, none of these techniques is able to handle uncertain contour trees although any uncertainty of the volume data inevitably results in partially uncertain contour trees. In this work, we visualize uncertain contour trees...... by combining the contour trees of two morphologically filtered versions of a volume data set, which represent the range of uncertainty. These two contour trees are combined and visualized within a single image such that a range of potential contour trees is represented by the resulting visualization. Thus...

  13. Entity resolution for uncertain data

    NARCIS (Netherlands)

    Ayat, N.; Akbarinia, R.; Afsarmanesh, H.; Valduriez, P.

    2012-01-01

    Entity resolution (ER), also known as duplicate detection or record matching, is the problem of identifying the tuples that represent the same real world entity. In this paper, we address the problem of ER for uncertain data, which we call ERUD. We propose two different approaches for the ERUD

  14. Preparing for an Uncertain Forecast

    Science.gov (United States)

    Karolak, Eric

    2011-01-01

    Navigating the world of government relations and public policy can be a little like predicting the weather. One can't always be sure what's in store or how it will affect him/her down the road. But there are common patterns and a few basic steps that can help one best prepare for a change in the forecast. Though the forecast is uncertain, early…

  15. Emergence of Ceftazidime-Avibactam Resistance and Restoration of Carbapenem Susceptibility inKlebsiella pneumoniaeCarbapenemase-ProducingK pneumoniae: A Case Report and Review of Literature.

    Science.gov (United States)

    Shields, Ryan K; Nguyen, M Hong; Press, Ellen G; Chen, Liang; Kreiswirth, Barry N; Clancy, Cornelius J

    2017-01-01

    We used meropenem to successfully treat a patient with bacteremia due to ceftazidime-avibactam-resistant, meropenem- susceptible Klebsiella pneumoniae that carried mutant bla KPC-3 . Meropenem was bactericidal against ceftazidime-avibactam- resistant K pneumoniae isolates in vitro. Nevertheless, the role of carbapenems in treating such infections remains uncertain, because meropenem resistance is selected readily during passage experiments.

  16. Gondwanamyia, a new empidoid (Diptera genus of uncertain placement

    Directory of Open Access Journals (Sweden)

    Bradley J. Sinclair

    2016-10-01

    Full Text Available A new minute-size empidoid fly genus, Gondwanamyia gen. n. and two new species (G. chilensis Cumming & Saigusa, sp. n., G. zealandica Sinclair & Brooks, sp. n. are described, illustrated, and their distributions mapped. The family and subfamily assignments remain uncertain, but features of the female terminalia potentially suggest Trichopezinae (Brachystomatidae.

  17. Investment under Uncertain Climate Policy

    DEFF Research Database (Denmark)

    Barradale, Merrill Jones

    2014-01-01

    This paper introduces the concept of payment probability as an important component of carbon risk (the financial risk associated with CO2 emissions under uncertain climate policy). In modeling power plant investment decisions, most existing literature uses the expected carbon price (e.g., the price...... actually be faced in the case of a particular investment. This concept helps explain both the surge of activity in 2005–2006 and the subsequent decline in interest in coal-fired power plant development in the U.S. The data for this case study comes from an extensive online survey of 700 U.S. energy...... design better incentives for investing in low-carbon technologies...

  18. Susceptibility and reactivity in polysensitized individuals following controlled induction

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Carlsen, Berit C; Johansen, Jeanne Duus

    2010-01-01

    It is uncertain whether polysensitized patients acquire multiple allergies only because of a high degree of exposure to environmental allergens, or because of being highly susceptible to developing contact allergy.......It is uncertain whether polysensitized patients acquire multiple allergies only because of a high degree of exposure to environmental allergens, or because of being highly susceptible to developing contact allergy....

  19. Lawn Care Pesticides. Risks Remain Uncertain While Prohibited Safety Claims Continue

    Science.gov (United States)

    1990-03-23

    Endothall Herbicide NO Glyphosate Herbicide YES Isoxaben Herbicide a MCPA (2-methyl-4-chlorophenoxyacetic acid) Herbicide YES MCPP (potassium salt...concerns Special Review status 2,4-0 Carcinogenicity Preliminary notificationa DDVP (dichlorvos) Oncogenicity Special Review in processb Maneb (EBDOC...of two epidemiological studies bEPA will reassess carcinogenic potential when additional oncogenicity data are received. CEPA announced a preliminary

  20. Decision Making Under Uncertain Categorization

    Directory of Open Access Journals (Sweden)

    Stephanie Ying-Fen Chen

    2014-09-01

    Full Text Available Two experiments investigated how category information is used in decision making under uncertainty and whether the framing of category information influences how it is used. Subjects were presented with vignettes in which the categorization of a critical item was ambiguous and were asked to choose among a set of actions with the goal of attaining the desired outcome for the main character in the story. The normative decision making strategy was to base the decision on all possible categories; however, research on a related topic, category-based induction, has found that people often only consider a single category when making predictions when categorization is uncertain. These experiments found that subjects tend to consider multiple categories when making decisions, but do so both when it is and is not appropriate, suggesting that use of multiple categories is not driven by an understanding of what categories are and are not relevant to the decision. Similarly, although a framing manipulation increased the rate of multiple-category use, it did so in situations in which multiple-category use was and was not appropriate.

  1. Rational suicide: uncertain moral ground.

    Science.gov (United States)

    Rich, Karen L; Butts, Janie B

    2004-05-01

    The ambiguities involving end-of-life issues, such as physician-assisted suicide and voluntary stopping of eating and drinking, have caused a blurring of the definition of rational suicide and have prompted rich dialogue with moral deliberations that seem to be on disparate paths among bioethicists and other health care professionals. With the evolution of advanced medical technology extending life expectancy in older, disabled, and terminally ill people, rational suicide has become a critical issue of debate. The purpose of this article is to address the ethical positions supporting and opposing rational suicide and to consider whether coherence can be achieved through an ethic of care. Attitudes towards suicide have been controversial, varying from acceptance to non-acceptance depending on social, political and religious influences. Nursing attitudes are no different from general societal attitudes and, consequently, nurses are treading on uncertain moral ground. Nurses who have not reflected on the moral issues involved with rational suicide may be unprepared psychologically and professionally when working with patients who may be contemplating such actions.

  2. Fish remains and humankind

    Directory of Open Access Journals (Sweden)

    Andrew K G Jones

    1997-08-01

    Full Text Available The four papers in this issue represent a trawl of the reports presented to the Fourth meeting of the International Council for Archaeozoology (ICAZ Fish Remains Working Group, which met at the University of York in 1987. The conference discussed material from many parts of the world - from Australasia to the north-west coast of America - and many eras, ranging in date from the early Pleistocene to the 1980s. It demonstrated both the variety of work being carried out and the growing interest in ancient fish remains. Internet Archaeology plans to publish other batches of papers from this conference. These reports will demonstrate the effort being made to distinguish between assemblages of fish remains which have been deposited by people and those which occur in ancient deposits as a result of the action of other agents. To investigate this area, experiments with modern material and observations of naturally occurring fish bone assemblages are supplemented with detailed analysis of ancient and modern fish remains. The papers published here illustrate the breadth of research into osteology, biogeography, documentary research, and the practicalities of recovering fish remains. Read, digest and enjoy them! Using the Internet for publishing research papers is not only ecologically sound (saving paper, etc. it disseminates scholarship to anyone anywhere on the planet with access to what is gradually becoming necessary technology in the late 20th century. Hopefully, future groups of papers will include video and audio material recorded at the conference, and so enable those who could not attend to gain further insights into the meeting and the scholarship underpinning this area of research.

  3. Uncertain dynamical systems stability and motion control

    CERN Document Server

    Martynyuk, AA

    2011-01-01

    This self-contained book provides systematic instructive analysis of uncertain systems of the following types: ordinary differential equations, impulsive equations, equations on time scales, singularly perturbed differential equations, and set differential equations. Each chapter contains new conditions of stability of unperturbed motion of the above-mentioned type of equations, along with some applications. Without assuming specific knowledge of uncertain dynamical systems, the book includes many fundamental facts about dynamical behaviour of its solutions.Giving a concise review of current r

  4. Fuzzy controller for an uncertain dynamical system

    DEFF Research Database (Denmark)

    Kulczycki, P.; Wisniewski, Rafal

    2002-01-01

    The present paper deals with the time-optimal control for mechanical systems with uncertain load. A fuzzy approach is used in the design of suboptimal feedback controllers, robust with respect to the load. Statistical kernel estimators are used for the specification of crucial parameters. The met......The present paper deals with the time-optimal control for mechanical systems with uncertain load. A fuzzy approach is used in the design of suboptimal feedback controllers, robust with respect to the load. Statistical kernel estimators are used for the specification of crucial parameters...

  5. Learning to Learn about Uncertain Feedback

    Science.gov (United States)

    Faraut, Mailys C. M.; Procyk, Emmanuel; Wilson, Charles R. E.

    2016-01-01

    Unexpected outcomes can reflect noise in the environment or a change in the current rules. We should ignore noise but shift strategy after rule changes. How we learn to do this is unclear, but one possibility is that it relies on learning to learn in uncertain environments. We propose that acquisition of latent task structure during learning to…

  6. Quality Measures in Uncertain Data Management

    NARCIS (Netherlands)

    de Keijzer, Ander; van Keulen, Maurice; Prade, H.; Subrahmanian, V.S.

    2007-01-01

    Many applications deal with data that is uncertain. Some examples are applications dealing with sensor information, data integration applications and healthcare applications. Instead of these applications having to deal with the uncertainty, it should be the responsibility of the DBMS to manage all

  7. Globalized robust optimization for nonlinear uncertain inequalities

    NARCIS (Netherlands)

    Ben-Tal, A.; Brekelmans, Ruud; den Hertog, Dick; Vial, J.P.

    Robust optimization is a methodology that can be applied to problems that are affected by uncertainty in their parameters. The classical robust counterpart of a problem requires the solution to be feasible for all uncertain parameter values in a so-called uncertainty set and offers no guarantees for

  8. Uncertain climate policy and the green paradox

    NARCIS (Netherlands)

    Smulders, Sjak A.; Tsur, Y.; Zemel, A.; Moser, E.; Semmler, W.; Tragler, G.; Veliov, V.

    2014-01-01

    Unintended consequences of announcing a climate policy well in advance of its implementation have been studied in a variety of situations. We show that a phenomenon akin to the so-called “Green-Paradox” holds also when the policy implementation date is uncertain. Governments are compelled, by

  9. Robust scheduling in an uncertain environment

    NARCIS (Netherlands)

    Wilson, M.

    2016-01-01

    This thesis presents research on scheduling in an uncertain environment, which forms a part of the rolling stock life cycle logistics applied research and development program funded by Dutch railway industry companies. The focus therefore lies on scheduling of maintenance operations on rolling stock

  10. Counselling framework for moderate-penetrance cancer-susceptibility mutations

    OpenAIRE

    Tung, Nadine; Domchek, Susan M.; Stadler, Zsofia; Nathanson, Katherine L.; Couch, Fergus; Garber, Judy E.; Offit, Kenneth; Robson, Mark E.

    2016-01-01

    The use of multigene panels for the assessment of cancer susceptibility is expanding rapidly in clinical practice, particularly in the USA, despite concerns regarding the uncertain clinical validity for some gene variants and the uncertain clinical utility of most multigene panels. So-called ?moderate-penetrance? gene mutations associated with cancer susceptibility are identified in approximately 2?5% of individuals referred for clinical testing; some of these mutations are potentially action...

  11. An Improved Memory State Feedback RMPC for Uncertain Constrained Linear Systems with Multiple Uncertain Delays

    OpenAIRE

    Qin, Weiwei; He, Bing; Zhao, Pengtao; Liu, Gang

    2015-01-01

    The problem of robust asymptotic stabilization is considered for a class of discrete-time uncertain linear systems with multiple uncertain time-delayed states and input constraints. Compared with other works in the literature, the proposed approach takes the information of the delayed states with the estimated time-delays indices into full consideration. Based on the predictive control principle of receding horizon optimization and Lyapunov stability theory combined with linear matrix inequal...

  12. Communicating Uncertain News in Cancer Consultations.

    Science.gov (United States)

    Alby, Francesca; Zucchermaglio, Cristina; Fatigante, Marilena

    2017-12-01

    In cancer communication, most of the literature is in the realm of delivering bad news while much less attention has been given to the communication of uncertain news around the diagnosis and the possible outcomes of the illness. Drawing on video-recorded cancer consultations collected in two Italian hospitals, this article analyzes three communication practices used by oncologists to interactionally manage the uncertainty during the visit: alternating between uncertain bad news and certain good news, anticipating scenarios, and guessing test results. Both diagnostic and personal uncertainties are not hidden to the patient, yet they are reduced through these practices. Such communication practices are present in 32 % of the visits in the data set, indicating that the interactional management of uncertainty is a relevant phenomenon in oncological encounters. Further studies are needed to improve both its understanding and its teaching.

  13. Modelling decision making in an uncertain environment

    OpenAIRE

    Bullen, Guy; Ouafae, Bennis; Kratz, Frédéric

    2010-01-01

    International audience; This article proposes a generative approach to decision making in a complex and uncertain environment, as n alternative to normative or descriptive approaches. A simple and intuitive graphical model provides management teams with a non-restrictive framework for thinking through their decisions. The second half of the article proposes a mathematical model to estimate the multiple influences between decisions in a complex project, whether they are direct or indirect. Thi...

  14. Restructuring Electricity Markets when Demand is Uncertain

    DEFF Research Database (Denmark)

    Boom, Anette; Buehler, Stefan

    2006-01-01

    We examine the effects of reorganizing electricity markets on capacity investments, retail prices and welfare when demand is uncertain. We study the following market configurations: (i) integrated monopoly, (ii) integrated duopoly with wholesale trade, and (iii) separated duopoly with wholesale...... are such that the separated (integrated) duopoly with wholesale trade performs best (worst) in terms of welfare.Keywords: Electricity, Investments, Generating Capacities, Vertical Integration, Monopoly and Competition.JEL-Classification: D42, D43, D44, L11, L12, L13...

  15. Constructor:synthesizing information about uncertain variables.

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, W. Troy (Applied Biomathematics, Setauket, NY); Ferson, Scott (Applied Biomathematics, Setauket, NY); Hajagos, Janos (Applied Biomathematics, Setauket, NY); Myers, David S. (Applied Biomathematics, Setauket, NY)

    2005-09-01

    Constructor is software for the Microsoft Windows microcomputer environment that facilitates the collation of empirical information and expert judgment for the specification of probability distributions, probability boxes, random sets or Dempster-Shafer structures from data, qualitative shape information, constraints on moments, order statistics, densities, and coverage probabilities about uncertain unidimensional quantities. These quantities may be real-valued, integer-valued or logical values.

  16. Crowd-sourcing with Uncertain Quality

    DEFF Research Database (Denmark)

    Papakonstantinou, Athanasios; Bogetoft, Peter

    This article addresses two important issues in crowd-sourcing: ex ante uncertainty about the quality and cost of different workers and strategic behaviour. We present a novel multi-dimensional auction that incentivises the workers to make partial enquiry into the task and to honestly report quality-cost...... estimates based on which the crowd-sourcer can choose the worker that offers the best value for money. The mechanism extends second score auction design to settings where the quality is uncertain and it provides incentives to both collect information and deliver desired qualities....

  17. Vessels Route Planning Problem with Uncertain Data

    Directory of Open Access Journals (Sweden)

    Tomasz Neumann

    2016-09-01

    Full Text Available The purpose of this paper is to find a solution for route planning in a transport networks, where the costs of tracks, factor of safety and travel time are ambiguous. This approach is based on the Dempster-Shafer theory and well known Dijkstra's algorithm. In this approach important are the influencing factors of the mentioned coefficients using uncertain possibilities presented by probability intervals. Based on these intervals the quality intervals of each route can be determined. Applied decision rules can be described by the end user.

  18. The Fourth International VLDB Workshop on Management of Uncertain Data

    NARCIS (Netherlands)

    Unknown, [Unknown; de Keijzer, Ander; van Keijzer, A.; van Keulen, M.; van Keulen, Maurice

    2010-01-01

    This is the fourth edition of the international VLDB workshop on Management of Uncertain Data. Previous editions of this workshop took place in New Zealand, Austria and France. Research on uncertain data has grown over the past few years. Besides workshops on the topic of uncertain data, also

  19. Generalization from uncertain and imprecise data

    Energy Technology Data Exchange (ETDEWEB)

    Bouchon-Meunier, B.; Marsala, C.; Rifqi, M. [Universite P. et M. Curie, Paris (France); Ramdani, M. [Universite P. et M. Curie, Paris (France)]|[Faculte des Sciences et Techniques, Mohammadia (Morocco)

    1996-12-31

    Most of the knowledge available about a given system is imperfect, which means imprecise, uncertain, qualitative, expressed in natural language with words which are generally vague. Some pieces of knowledge are numerical, obtained by means of measurements with more or less precise devices. They can also be incomplete, with unknown values for some elements of the system. Classification of objects, decision-making according to the description of the system, are well known problems which can be approached by various ways. Methods based on a generalization process appear very efficient when a list of already solved cases is available and sufficiently representative of all the possible cases. In this paper, we focus on the case where fuzzy sets are used to represent imperfect knowledge because of the capability of fuzzy sets to help managing imprecise data, possibly submitted to some non probabilistic uncertainty such as a subjective doubt. Fuzzy sets also present the interesting property to establish an interface between numerical and symbolic data and are interesting to use when both types of data are present. We suppose that the objects of the system are described by means of attributes, the value of which can be imprecise, uncertain or undetermined. Our purpose is to find rules enabling us to attach a class to any object of the system. We focus this study on two generalization methods based on the knowledge of a training set of objects associated with their descriptions and their classes.

  20. Sensitivity in risk analyses with uncertain numbers.

    Energy Technology Data Exchange (ETDEWEB)

    Tucker, W. Troy; Ferson, Scott

    2006-06-01

    Sensitivity analysis is a study of how changes in the inputs to a model influence the results of the model. Many techniques have recently been proposed for use when the model is probabilistic. This report considers the related problem of sensitivity analysis when the model includes uncertain numbers that can involve both aleatory and epistemic uncertainty and the method of calculation is Dempster-Shafer evidence theory or probability bounds analysis. Some traditional methods for sensitivity analysis generalize directly for use with uncertain numbers, but, in some respects, sensitivity analysis for these analyses differs from traditional deterministic or probabilistic sensitivity analyses. A case study of a dike reliability assessment illustrates several methods of sensitivity analysis, including traditional probabilistic assessment, local derivatives, and a ''pinching'' strategy that hypothetically reduces the epistemic uncertainty or aleatory uncertainty, or both, in an input variable to estimate the reduction of uncertainty in the outputs. The prospects for applying the methods to black box models are also considered.

  1. Parasite remains in archaeological sites

    Directory of Open Access Journals (Sweden)

    Françoise Bouchet

    2003-01-01

    Full Text Available Organic remains can be found in many different environments. They are the most significant source for paleoparasitological studies as well as for other paleoecological reconstruction. Preserved paleoparasitological remains are found from the driest to the moistest conditions. They help us to understand past and present diseases and therefore contribute to understanding the evolution of present human sociality, biology, and behavior. In this paper, the scope of the surviving evidence will be briefly surveyed, and the great variety of ways it has been preserved in different environments will be discussed. This is done to develop to the most appropriated techniques to recover remaining parasites. Different techniques applied to the study of paleoparasitological remains, preserved in different environments, are presented. The most common materials used to analyze prehistoric human groups are reviewed, and their potential for reconstructing ancient environment and disease are emphasized. This paper also urges increased cooperation among archaeologists, paleontologists, and paleoparasitologists.

  2. Minimum Redundancy Coding for Uncertain Sources

    CERN Document Server

    Baer, Michael B; Charalambous, Charalambos D

    2011-01-01

    Consider the set of source distributions within a fixed maximum relative entropy with respect to a given nominal distribution. Lossless source coding over this relative entropy ball can be approached in more than one way. A problem previously considered is finding a minimax average length source code. The minimizing players are the codeword lengths --- real numbers for arithmetic codes, integers for prefix codes --- while the maximizing players are the uncertain source distributions. Another traditional minimizing objective is the first one considered here, maximum (average) redundancy. This problem reduces to an extension of an exponential Huffman objective treated in the literature but heretofore without direct practical application. In addition to these, this paper examines the related problem of maximal minimax pointwise redundancy and the problem considered by Gawrychowski and Gagie, which, for a sufficiently small relative entropy ball, is equivalent to minimax redundancy. One can consider both Shannon-...

  3. Robust lyapunov controller for uncertain systems

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-02-23

    Various examples of systems and methods are provided for Lyapunov control for uncertain systems. In one example, a system includes a process plant and a robust Lyapunov controller configured to control an input of the process plant. The robust Lyapunov controller includes an inner closed loop Lyapunov controller and an outer closed loop error stabilizer. In another example, a method includes monitoring a system output of a process plant; generating an estimated system control input based upon a defined output reference; generating a system control input using the estimated system control input and a compensation term; and adjusting the process plant based upon the system control input to force the system output to track the defined output reference. An inner closed loop Lyapunov controller can generate the estimated system control input and an outer closed loop error stabilizer can generate the system control input.

  4. Probabilistic Graph Layout for Uncertain Network Visualization.

    Science.gov (United States)

    Schulz, Christoph; Nocaj, Arlind; Goertler, Jochen; Deussen, Oliver; Brandes, Ulrik; Weiskopf, Daniel

    2017-01-01

    We present a novel uncertain network visualization technique based on node-link diagrams. Nodes expand spatially in our probabilistic graph layout, depending on the underlying probability distributions of edges. The visualization is created by computing a two-dimensional graph embedding that combines samples from the probabilistic graph. A Monte Carlo process is used to decompose a probabilistic graph into its possible instances and to continue with our graph layout technique. Splatting and edge bundling are used to visualize point clouds and network topology. The results provide insights into probability distributions for the entire network-not only for individual nodes and edges. We validate our approach using three data sets that represent a wide range of network types: synthetic data, protein-protein interactions from the STRING database, and travel times extracted from Google Maps. Our approach reveals general limitations of the force-directed layout and allows the user to recognize that some nodes of the graph are at a specific position just by chance.

  5. Conservation planning with uncertain climate change projections.

    Directory of Open Access Journals (Sweden)

    Heini Kujala

    Full Text Available Climate change is affecting biodiversity worldwide, but conservation responses are constrained by considerable uncertainty regarding the magnitude, rate and ecological consequences of expected climate change. Here we propose a framework to account for several sources of uncertainty in conservation prioritization. Within this framework we account for uncertainties arising from (i species distributions that shift following climate change, (ii basic connectivity requirements of species, (iii alternative climate change scenarios and their impacts, (iv in the modelling of species distributions, and (v different levels of confidence about present and future. When future impacts of climate change are uncertain, robustness of decision-making can be improved by quantifying the risks and trade-offs associated with climate scenarios. Sensible prioritization that accounts simultaneously for the present and potential future distributions of species is achievable without overly jeopardising present-day conservation values. Doing so requires systematic treatment of uncertainties and testing of the sensitivity of results to assumptions about climate. We illustrate the proposed framework by identifying priority areas for amphibians and reptiles in Europe.

  6. Free Vibration of Uncertain Unsymmetrically Laminated Beams

    Science.gov (United States)

    Kapania, Rakesh K.; Goyal, Vijay K.

    2001-01-01

    Monte Carlo Simulation and Stochastic FEA are used to predict randomness in the free vibration response of thin unsymmetrically laminated beams. For the present study, it is assumed that randomness in the response is only caused by uncertainties in the ply orientations. The ply orientations may become random or uncertain during the manufacturing process. A new 16-dof beam element, based on the first-order shear deformation beam theory, is used to study the stochastic nature of the natural frequencies. Using variational principles, the element stiffness matrix and mass matrix are obtained through analytical integration. Using a random sequence a large data set is generated, containing possible random ply-orientations. This data is assumed to be symmetric. The stochastic-based finite element model for free vibrations predicts the relation between the randomness in fundamental natural frequencies and the randomness in ply-orientation. The sensitivity derivatives are calculated numerically through an exact formulation. The squared fundamental natural frequencies are expressed in terms of deterministic and probabilistic quantities, allowing to determine how sensitive they are to variations in ply angles. The predicted mean-valued fundamental natural frequency squared and the variance of the present model are in good agreement with Monte Carlo Simulation. Results, also, show that variations between plus or minus 5 degrees in ply-angles can affect free vibration response of unsymmetrically and symmetrically laminated beams.

  7. uncertain dynamic systems on time scales

    Directory of Open Access Journals (Sweden)

    V. Lakshmikantham

    1995-01-01

    Full Text Available A basic feedback control problem is that of obtaining some desired stability property from a system which contains uncertainties due to unknown inputs into the system. Despite such imperfect knowledge in the selected mathematical model, we often seek to devise controllers that will steer the system in a certain required fashion. Various classes of controllers whose design is based on the method of Lyapunov are known for both discrete [4], [10], [15], and continuous [3–9], [11] models described by difference and differential equations, respectively. Recently, a theory for what is known as dynamic systems on time scales has been built which incorporates both continuous and discrete times, namely, time as an arbitrary closed sets of reals, and allows us to handle both systems simultaneously [1], [2], [12], [13]. This theory permits one to get some insight into and better understanding of the subtle differences between discrete and continuous systems. We shall, in this paper, utilize the framework of the theory of dynamic systems on time scales to investigate the stability properties of conditionally invariant sets which are then applied to discuss controlled systems with uncertain elements. For the notion of conditionally invariant set and its stability properties, see [14]. Our results offer a new approach to the problem in question.

  8. Probabilistic logic networks a comprehensive framework for uncertain inference

    CERN Document Server

    Goertzel, Ben; Goertzel, Izabela Freire; Heljakka, Ari

    2008-01-01

    This comprehensive book describes Probabilistic Logic Networks (PLN), a novel conceptual, mathematical and computational approach to uncertain inference. A broad scope of reasoning types are considered.

  9. New hominin remains from Uzbekistan.

    Science.gov (United States)

    Glantz, Michelle; Viola, Bence; Wrinn, Patrick; Chikisheva, Tatiana; Derevianko, Anatoly; Krivoshapkin, Andrei; Islamov, Uktur; Suleimanov, Rustam; Ritzman, Terrence

    2008-08-01

    Although the Paleolithic occupations of Uzbekistan and the neighboring foothill regions of Tajikistan and Kazakhstan are well-documented, almost no hominin fossil material has been discovered in the area since Teshik-Tash 1 in 1938. Here we describe and offer a preliminary comparative framework for hominin remains that were recovered in 2003 from two Middle Paleolithic sites in Uzbekistan, Obi-Rakhmat Grotto and Anghilak Cave. The description of Teshik-Tash as a Neandertal and the preponderance of lithic assemblages identified as Mousterian in character has supported the interpretation of the region as the eastern-most extent of the Neandertal range. The material from Obi-Rakhmat (OR-1), a subadult represented by part of a permanent maxillary dentition and a fragmentary cranium, expresses a relatively Neandertal-like dentition coupled with more ambiguous cranial anatomy. The remains from Anghilak Cave include a non-diagnostic, diminutive right fifth metatarsal (AH-1). These findings are important additions to the Central Asia hominin fossil record.

  10. Population, resources, environment: an uncertain future.

    Science.gov (United States)

    Repetto, R

    1987-07-01

    This issue analyzes the economic and environmental consequences of rapid population growth in developing countries (LDC), the population decline in developed countries, the limits that life on a finite planet impose on economic and demographic expansion and progress, and the proper governmental response to promote the welfare of its current and future citizens. The links between population growth, resource use, and environmental quality are too complex to permit straightforward generalizations about direct causal relationships. However, rapid population growth has increased the number of poor people in LDC, thus contributing to degradation of the environment and the renewable resources of land, water, and nonhuman species on which humans depend. Demands of the rich industrial countries have also generated environmental pressures and have been foremost in consumption of the nonrenewable resources of fossil fuels, metals, and nonmetallic minerals. On the other hand, population and economic growth have also stimulated technological and management changes that help supply and use resources more effectively. Wide variations in the possible ultimate size of world population and accelerating technological change make future interrelationships of population, resources, and the environment uncertain as well as complex. Those interrelationships are mediated largely by government policies. Responsible governments can bring about a sustainable balance in the population/resource/environment equation by adopting population and development policies that experience has shown could reduce future population numbers in LDC below the additional 5 billion indicated in current UN medium projections. This coupled with proven management programs in both LDC and developed countries could brake and reverse the depletion and degradation of natural resources.

  11. How safely can post-term pregnancies with uncertain gestational ...

    African Journals Online (AJOL)

    Objective. To review whether 2 weeks' follow-up is safe for women at 42 weeks with an uncertain gestational age (GA) and amniotic fluid index (AFI) of ≥10 cm, as well as reassuring cardiotocography (CTG). Methods. A retrospective descriptive study of women with an uncertain GA of 42 weeks was done at Tygerberg ...

  12. Millennial Teachers and Multiculturalism: Considerations for Teaching in Uncertain Times

    Science.gov (United States)

    Hallman, Heidi L.

    2017-01-01

    Purpose: This paper aims to explore the intersection of generational traits of millennial teachers, multiculturalism and teaching in an era of Uncertain Times. Uncertain Times, as a framework for the paper, characterizes changing aspects of the current era in which we live, such as the rise of the internet and interconnectivity, globalization and…

  13. Convective Weather Avoidance with Uncertain Weather Forecasts

    Science.gov (United States)

    Karahan, Sinan; Windhorst, Robert D.

    2009-01-01

    Convective weather events have a disruptive impact on air traffic both in terminal area and in en-route airspaces. In order to make sure that the national air transportation system is safe and efficient, it is essential to respond to convective weather events effectively. Traffic flow control initiatives in response to convective weather include ground delay, airborne delay, miles-in-trail restrictions as well as tactical and strategic rerouting. The rerouting initiatives can potentially increase traffic density and complexity in regions neighboring the convective weather activity. There is a need to perform rerouting in an intelligent and efficient way such that the disruptive effects of rerouting are minimized. An important area of research is to study the interaction of in-flight rerouting with traffic congestion or complexity and developing methods that quantitatively measure this interaction. Furthermore, it is necessary to find rerouting solutions that account for uncertainties in weather forecasts. These are important steps toward managing complexity during rerouting operations, and the paper is motivated by these research questions. An automated system is developed for rerouting air traffic in order to avoid convective weather regions during the 20- minute - 2-hour time horizon. Such a system is envisioned to work in concert with separation assurance (0 - 20-minute time horizon), and longer term air traffic management (2-hours and beyond) to provide a more comprehensive solution to complexity and safety management. In this study, weather is dynamic and uncertain; it is represented as regions of airspace that pilots are likely to avoid. Algorithms are implemented in an air traffic simulation environment to support the research study. The algorithms used are deterministic but periodically revise reroutes to account for weather forecast updates. In contrast to previous studies, in this study convective weather is represented as regions of airspace that pilots

  14. Robust Control with Enlaeged Interval of Uncertain Parameters

    Directory of Open Access Journals (Sweden)

    Marek Keresturi

    2002-01-01

    Full Text Available Robust control is advantageous for systems with defined interval of uncertain parameters. This can be substantially enlarged dividing it into a few sub-intervals. Corresponding controllers for each of them may be set after approximate identification of some uncertain plant parameters. The paper deals with application of the pole region assignment method for position control of the crane crab. The same track form is required for uncertain burden mass and approximate value of rope length. Measurement of crab position and speed is supposed, burden deviation angle is observed. Simulation results have verified feasibility of this design procedure.

  15. Stability Analysis of Train Movement with Uncertain Factors

    Directory of Open Access Journals (Sweden)

    JingJing Ye

    2015-01-01

    Full Text Available We propose a new traffic model which is based on the traditional OV (optimal velocity car-following model. Here, some realistic factors are regarded as uncertain quantity, such as the headway distance. Our aim is to analyze and discuss the stability of car-following model under the constraint of uncertain factors. Then, according to the principle of expected value in fuzzy theory, an improved OV traffic model is constructed. Simulation results show that our proposed model can avoid collisions effectively under uncertain environment, and its stability can also be improved. Moreover, we discuss its stability as some parameters change, such as the relaxation time.

  16. Food security measures during uncertain climatic conditions in Nigeria

    African Journals Online (AJOL)

    Food security measures during uncertain climatic conditions in Nigeria. ... Journal Home > Vol 9, No 2 (2009) >. Log in or Register to get access to full text downloads. ... Keywords: Climate-variability, confidence limits, productivity, drought

  17. Uncertain R&D, backstop technology and GHGs stabilization

    OpenAIRE

    Bosetti, Valentina; Tavoni, Massimo

    2009-01-01

    This paper analyses optimal investments in innovation when dealing with a stringent climate target and with the uncertain effectiveness of R&D. The innovation needed to achieve the deep cut in emissions is modelled by a backstop carbon-free technology whose cost depends on R&D investments. To better represent the process of technological progress, we assume that R&D effectiveness is uncertain. By means of a simple analytical model, we show how accounting for the uncertainty that characterizes...

  18. A Transportation Problem with Uncertain Costs and Random Supplies

    Directory of Open Access Journals (Sweden)

    Haiying Guo

    2015-06-01

    Full Text Available Transportation problem is an optimization problem. In general, it was studied under random or uncertain condition. Considering the recent complexity, it is not enough to make should be a perfect transportation plan only based on. Usually, there is not only uncertainty but also randomness in many systems. In this paper, the aim is to investigate a transportation problem under uncertain and random environment. As a result, a conceptual uncertain random model is proposed for the problem, where the supplies are considered as random variables, and the costs and the demands are uncertain variables. By minimizing the expected value of uncertain objective function and taking confidence levels on constraints, transforming the model into a crisp mathematical form is the main conclusion. By minimizing the expected value of uncertain objective function and taking confidence levels on constraints, the above model can be turned to a mathematical form. Then transforming the model into a typical mathematical programming model is the main conclusion by using uncertainty theory and probability theory. At the end, a numerical example is given to show the feasibility of the model.

  19. Omega-3 and dyslexia: Uncertain connection.

    Science.gov (United States)

    Zelcer, Michal; Goldman, Ran D

    2015-09-01

    In light of the increase in the number of school-aged children diagnosed with dyslexia, what is the role of omega-3 supplements in the management of this condition? Dyslexia is the most common learning disability and is known to have multifactorial causes. Recent evidence suggests that there is a connection between defects in highly unsaturated fatty acid metabolism and neurodevelopmental disorders such as dyslexia. While the benefit of omega-3 supplementation for children with dyslexia has been studied, evidence remains limited. Unified diagnostic criteria for dyslexia, objective measures of fatty acid deficiency, and close monitoring of dietary intake are some of the factors that would improve the quality of research in the field. Copyright© the College of Family Physicians of Canada.

  20. Breast cancer screening and cost-effectiveness; policy alternatives, quality of life considerations and the possible impact of uncertain factors

    NARCIS (Netherlands)

    de Koning, H. J.; van Ineveld, B. M.; van Oortmarssen, G. J.; de Haes, J. C.; Collette, H. J.; Hendriks, J. H.; van der Maas, P. J.

    1991-01-01

    Mammographic screening for women aged 50-70 is effective in reducing breast cancer mortality, but the impact on quality of life and the attainable mortality reduction remain to be discussed. The consequences of expanding screening programmes to include women in other age groups are uncertain. We

  1. Reducing New Orleans Residential Flood Risk in an Uncertain Future Using Non-Structural Risk Mitigation

    Science.gov (United States)

    Fischbach, J. R.; Groves, D.; Johnson, D.

    2010-12-01

    Five years after Hurricane Katrina devastated the Gulf Coast, the long-term future of the City of New Orleans remains uncertain. This paper addresses one of New Orleans' most critical challenges: how to make the city more resilient and less vulnerable to future flood damages. Despite recent upgrades to the protection system surrounding the city designed to protect against floods with a 1-in-100 (1%) annual chance of occurrence, New Orleans remains vulnerable to lower-frequency, high-damage events. In addition, uncertain factors that influence flood risk, including coastal land loss and subsidence, rising sea levels, and population recovery and growth, may lead to increasing risk over time. Current proposals for risk reduction in New Orleans and South Louisiana, however, have not fully accounted for these key uncertain drivers. Rather than focus on additional large-scale structural infrastructure investments, this paper considers proposals to augment the existing protection system with ``non-structural" risk mitigation programs. Non-structural risk mitigation includes incentives for elevating existing or new structures, revised building codes, incentives for relocation to lower risk areas, and land use restrictions designed to curtail future growth in the floodplain. This research estimates the risk reduction benefits and implementation costs of non-structural risk mitigation strategies focused on single-family or small multi-family homes in New Orleans. We draw from existing risk models to develop a low-resolution scenario generator, NOLArisk, designed to produce first-order estimates of property risk from 2011-2060 across a range of uncertain future scenarios. We then apply exploratory modeling and Robust Decision Making (RDM) methods to a) suggest strategies that balance risk reduction and implementation costs across many or most plausible futures, and b) identify scenarios in which current alternatives yield negative net economic benefits or excessive levels of

  2. Bayesian source localization with uncertain Green's function in an uncertain shallow water ocean.

    Science.gov (United States)

    Le Gall, Yann; Dosso, Stan E; Socheleau, François-Xavier; Bonnel, Julien

    2016-03-01

    Matched-field acoustic source localization is a challenging task when environmental properties of the oceanic waveguide are not precisely known. Errors in the assumed environment (mismatch) can cause severe degradations in localization performance. This paper develops a Bayesian approach to improve robustness to environmental mismatch by considering the waveguide Green's function to be an uncertain random vector whose probability density accounts for environmental uncertainty. The posterior probability density is integrated over the Green's function probability density to obtain a joint marginal probability distribution for source range and depth, accounting for environmental uncertainty and quantifying localization uncertainty. Because brute-force integration in high dimensions can be costly, an efficient method is developed in which the multi-dimensional Green's function integration is approximated by one-dimensional integration over a suitably defined correlation measure. An approach to approximate the Green's function covariance matrix, which represents the environmental mismatch, is developed based on modal analysis. Examples are presented to illustrate the method and Monte-Carlo simulations are carried out to evaluate its performance relative to other methods. The proposed method gives efficient, reliable source localization and uncertainties with improved robustness toward environmental mismatch.

  3. MAGDM linear-programming models with distinct uncertain preference structures.

    Science.gov (United States)

    Xu, Zeshui S; Chen, Jian

    2008-10-01

    Group decision making with preference information on alternatives is an interesting and important research topic which has been receiving more and more attention in recent years. The purpose of this paper is to investigate multiple-attribute group decision-making (MAGDM) problems with distinct uncertain preference structures. We develop some linear-programming models for dealing with the MAGDM problems, where the information about attribute weights is incomplete, and the decision makers have their preferences on alternatives. The provided preference information can be represented in the following three distinct uncertain preference structures: 1) interval utility values; 2) interval fuzzy preference relations; and 3) interval multiplicative preference relations. We first establish some linear-programming models based on decision matrix and each of the distinct uncertain preference structures and, then, develop some linear-programming models to integrate all three structures of subjective uncertain preference information provided by the decision makers and the objective information depicted in the decision matrix. Furthermore, we propose a simple and straightforward approach in ranking and selecting the given alternatives. It is worth pointing out that the developed models can also be used to deal with the situations where the three distinct uncertain preference structures are reduced to the traditional ones, i.e., utility values, fuzzy preference relations, and multiplicative preference relations. Finally, we use a practical example to illustrate in detail the calculation process of the developed approach.

  4. Uncertain behaviours of integrated circuits improve computational performance.

    Science.gov (United States)

    Yoshimura, Chihiro; Yamaoka, Masanao; Hayashi, Masato; Okuyama, Takuya; Aoki, Hidetaka; Kawarabayashi, Ken-ichi; Mizuno, Hiroyuki

    2015-11-20

    Improvements to the performance of conventional computers have mainly been achieved through semiconductor scaling; however, scaling is reaching its limitations. Natural phenomena, such as quantum superposition and stochastic resonance, have been introduced into new computing paradigms to improve performance beyond these limitations. Here, we explain that the uncertain behaviours of devices due to semiconductor scaling can improve the performance of computers. We prototyped an integrated circuit by performing a ground-state search of the Ising model. The bit errors of memory cell devices holding the current state of search occur probabilistically by inserting fluctuations into dynamic device characteristics, which will be actualised in the future to the chip. As a result, we observed more improvements in solution accuracy than that without fluctuations. Although the uncertain behaviours of devices had been intended to be eliminated in conventional devices, we demonstrate that uncertain behaviours has become the key to improving computational performance.

  5. Fuzzy arithmetical stability analysis of uncertain machining systems

    Science.gov (United States)

    Hamann, Dominik; Walz, Nico-Philipp; Fischer, Achim; Hanss, Michael; Eberhard, Peter

    2018-01-01

    The dynamical behavior of machining processes with parameter uncertainties is analyzed using the possibilistic approach of fuzzy arithmetic. The concept is used to simulate and analyze uncertain models of different complexity. Emphasis is put on the analysis of dynamic stability and the inclusion of the uncertain parameters therein. The stability limits, which are defined by an implicit equation, yield two-dimensional fuzzy-valued results, so that standard solution methods are not directly applicable. Therefore, a general method for the solution of implicit equations is presented that may be applied to the stability analysis of arbitrary time-delayed systems. The presented method as well as a fuzzy sensitivity analysis are then applied to the stability analysis of exemplary systems. The propagation characteristic as well as the fuzzy sensitivity analysis allow to see the effect of uncertainties on the system output and quantify the effect of given uncertain parameters.

  6. The uncertain response in the bottlenosed dolphin (Tursiops truncatus).

    Science.gov (United States)

    Smith, J D; Schull, J; Strote, J; McGee, K; Egnor, R; Erb, L

    1995-12-01

    Humans respond adaptively to uncertainty by escaping or seeking additional information. To foster a comparative study of uncertainty processes, we asked whether humans and a bottlenosed dolphin (Tursiops truncatus) would use similarly a psychophysical uncertain response. Human observers and the dolphin were given 2 primary discrimination responses and a way to escape chosen trials into easier ones. Humans escaped sparingly from the most difficult trials near threshold that left them demonstrably uncertain of the stimulus. The dolphin performed nearly identically. The behavior of both species is considered from the perspectives of signal detection theory and optimality theory, and its appropriate interpretation is discussed. Human and dolphin uncertain responses seem to be interesting cognitive analogs and may depend on cognitive or controlled decisional mechanisms. The capacity to monitor ongoing cognition, and use uncertainty appropriately, would be a valuable adaptation for animal minds. This recommends uncertainty processes as an important but neglected area for future comparative research.

  7. Gearbox design for uncertain load requirements using active robust optimization

    Science.gov (United States)

    Salomon, Shaul; Avigad, Gideon; Purshouse, Robin C.; Fleming, Peter J.

    2016-04-01

    Design and optimization of gear transmissions have been intensively studied, but surprisingly the robustness of the resulting optimal design to uncertain loads has never been considered. Active Robust (AR) optimization is a methodology to design products that attain robustness to uncertain or changing environmental conditions through adaptation. In this study the AR methodology is utilized to optimize the number of transmissions, as well as their gearing ratios, for an uncertain load demand. The problem is formulated as a bi-objective optimization problem where the objectives are to satisfy the load demand in the most energy efficient manner and to minimize production cost. The results show that this approach can find a set of robust designs, revealing a trade-off between energy efficiency and production cost. This can serve as a useful decision-making tool for the gearbox design process, as well as for other applications.

  8. Nonlinear robust hierarchical control for nonlinear uncertain systems

    Directory of Open Access Journals (Sweden)

    Leonessa Alexander

    1999-01-01

    Full Text Available A nonlinear robust control-system design framework predicated on a hierarchical switching controller architecture parameterized over a set of moving nominal system equilibria is developed. Specifically, using equilibria-dependent Lyapunov functions, a hierarchical nonlinear robust control strategy is developed that robustly stabilizes a given nonlinear system over a prescribed range of system uncertainty by robustly stabilizing a collection of nonlinear controlled uncertain subsystems. The robust switching nonlinear controller architecture is designed based on a generalized (lower semicontinuous Lyapunov function obtained by minimizing a potential function over a given switching set induced by the parameterized nominal system equilibria. The proposed framework robustly stabilizes a compact positively invariant set of a given nonlinear uncertain dynamical system with structured parametric uncertainty. Finally, the efficacy of the proposed approach is demonstrated on a jet engine propulsion control problem with uncertain pressure-flow map data.

  9. Polymorphic Uncertain Linear Programming for Generalized Production Planning Problems

    Directory of Open Access Journals (Sweden)

    Xinbo Zhang

    2014-01-01

    Full Text Available A polymorphic uncertain linear programming (PULP model is constructed to formulate a class of generalized production planning problems. In accordance with the practical environment, some factors such as the consumption of raw material, the limitation of resource and the demand of product are incorporated into the model as parameters of interval and fuzzy subsets, respectively. Based on the theory of fuzzy interval program and the modified possibility degree for the order of interval numbers, a deterministic equivalent formulation for this model is derived such that a robust solution for the uncertain optimization problem is obtained. Case study indicates that the constructed model and the proposed solution are useful to search for an optimal production plan for the polymorphic uncertain generalized production planning problems.

  10. NATO’s Uncertain Future is Demography Destiny

    Science.gov (United States)

    2009-01-01

    ndupress .ndu.edu issue 53, 2 d quarter 2009 / JFQ 51 NATO’s UNcerTAiN FUTUre is Demography Destiny? By J e f f r e y S i m o n T he North...Uncertain Future Is Demography Destiny? 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK... Demography Destiny? As the French philosopher August Comte suggested in his now-famous formula, a society’s demographic inheritance can indeed be a

  11. Robust Stabilization of Nonlinear Systems with Uncertain Varying Control Coefficient

    Directory of Open Access Journals (Sweden)

    Zaiyue Yang

    2014-01-01

    Full Text Available This paper investigates the stabilization problem for a class of nonlinear systems, whose control coefficient is uncertain and varies continuously in value and sign. The study emphasizes the development of a robust control that consists of a modified Nussbaum function to tackle the uncertain varying control coefficient. By such a method, the finite-time escape phenomenon has been prevented when the control coefficient is crossing zero and varying its sign. The proposed control guarantees the asymptotic stabilization of the system and boundedness of all closed-loop signals. The control performance is illustrated by a numerical simulation.

  12. Uncertain Portfolio Selection with Background Risk and Liquidity Constraint

    Directory of Open Access Journals (Sweden)

    Jia Zhai

    2017-01-01

    Full Text Available This paper discusses an uncertain portfolio selection problem with consideration of background risk and asset liquidity. In addition, the transaction costs are also considered. The security returns, background asset return, and asset liquidity are estimated by experienced experts instead of historical data. Regarding them as uncertain variables, a mean-risk model with background risk, liquidity, and transaction costs is proposed for portfolio selection and the crisp forms of the model are provided when security returns obey different uncertainty distributions. Moreover, for better understanding of the impact of background risk and liquidity on portfolio selection, some important theorems are proved. Finally, numerical experiments are presented to illustrate the modeling idea.

  13. Search for new breast cancer susceptibility genes

    NARCIS (Netherlands)

    Oldenburg, Rogier Abel

    2008-01-01

    This thesis describes the search for new high-risk breast cancer susceptibility genes by linkage analysis. To date 20-25% of familial breast cancer is explained by mutations in the high-risk BRCA1 and BRCA2 breast cancer susceptibility genes. For the remaining families the genetic etiology is

  14. Uncertain soil moisture feedbacks in model projections of Sahel precipitation

    Science.gov (United States)

    Berg, Alexis; Lintner, Benjamin R.; Findell, Kirsten; Giannini, Alessandra

    2017-06-01

    Given the uncertainties in climate model projections of Sahel precipitation, at the northern edge of the West African Monsoon, understanding the factors governing projected precipitation changes in this semiarid region is crucial. This study investigates how long-term soil moisture changes projected under climate change may feedback on projected changes of Sahel rainfall, using simulations with and without soil moisture change from five climate models participating in the Global Land Atmosphere Coupling Experiment-Coupled Model Intercomparison Project phase 5 experiment. In four out of five models analyzed, soil moisture feedbacks significantly influence the projected West African precipitation response to warming; however, the sign of these feedbacks differs across the models. These results demonstrate that reducing uncertainties across model projections of the West African Monsoon requires, among other factors, improved mechanistic understanding and constraint of simulated land-atmosphere feedbacks, even at the large spatial scales considered here.Plain Language SummaryClimate model projections of Sahel rainfall remain notoriously uncertain; understanding the physical processes responsible for this uncertainty is thus crucial. Our study focuses on analyzing the feedbacks of soil moisture changes on model projections of the West African Monsoon under global warming. Soil moisture-atmosphere interactions have been shown in prior studies to play an important role in this region, but the potential feedbacks of long-term soil moisture changes on projected precipitation changes have not been investigated specifically. To isolate these feedbacks, we use targeted simulations from five climate models, with and without soil moisture change. Importantly, we find that climate models exhibit soil moisture-precipitation feedbacks of different sign in this region: in some models soil moisture changes amplify precipitation changes (positive feedback), in others they dampen them

  15. ON A NUMERICAL ALGORITHM FOR UNCERTAIN SYSTEM ∫ Φ ...

    African Journals Online (AJOL)

    Administrator

    computing control variables in linear and non-linear optimization problems. This method is ... PD denotes the set of positive symmetric members of. NN. R × ..... ISSN 1597-6343. On a Numerical Algorithm for Uncertain System. We can now propose the following algorithm: Define )(. uJ by equation (16),. )( uH. ∇ by (39), then.

  16. Path Integration Applied to Structural Systems with Uncertain Properties

    DEFF Research Database (Denmark)

    Nielsen, Søren R.K.; Köylüoglu, H. Ugur

    Path integration (cell-to-cell mapping) method is applied to evaluate the joint probability density function (jpdf) of the response of the structural systems, with uncertain properties, subject to white noise excitation. A general methodology to deal with uncertainties is outlined and applied...

  17. R&D Collaboration with Uncertain Intellectual Property Rights

    DEFF Research Database (Denmark)

    Czarnitzki, Dirk; Hussinger, Katrin; Schneider, Cédric

    - uncertain intellectual property rights (IPR) lead to reduced collaboration between firms and may hinder the production of knowledge. This has implications for technology policy as R&D collaborations are exempt from anti-trust legislation in order to increase R&D in the economy. We argue that a functional...

  18. Robust decentralized output regulation for uncertain heterogeneous systems

    NARCIS (Netherlands)

    Persis, Claudio De; Liu, Hui; Cao, Ming

    2012-01-01

    We consider the problem in which N heterogeneous uncertain linear systems aim at tracking a reference signal generated by a given exosystem under the restriction that not all the systems are directly connected to the exosystem. To tackle this problem, the reference signal is reconstructed via local

  19. Distributed Robustness Analysis of Interconnected Uncertain Systems Using Chordal Decomposition

    DEFF Research Database (Denmark)

    Pakazad, Sina Khoshfetrat; Hansson, Anders; Andersen, Martin Skovgaard

    2014-01-01

    Large-scale interconnected uncertain systems commonly have large state and uncertainty dimensions. Aside from the heavy computational cost of performing robust stability analysis in a centralized manner, privacy requirements in the network can also introduce further issues. In this paper, we util...

  20. Identification of novel intronic BRCA1 variants of uncertain ...

    Indian Academy of Sciences (India)

    Identification of novel intronic BRCA1 variants of uncertain significance in a Thai hereditary breast cancer family ... Faculty of Pharmaceutical Sciences, Department of Pharmaceutical Chemistry, Laboratory of Pharmaceutical Biotechnology, Prince of Songkla University, Hat-Yai, Songkhla 90112, Thailand; Faculty of ...

  1. Internationalization for an Uncertain Future: Tensions, Paradoxes, and Possibilities

    Science.gov (United States)

    Stein, Sharon

    2017-01-01

    As higher education is increasingly called upon to play a central role in addressing the challenges and crises of today's complex, uncertain, and volatile world, internationalization efforts are intensifying. Emphasizing higher education as a space for critically-informed, socially accountable, and open-ended conversations about alternative…

  2. Multi-dimensional procurement auction under uncertain and asymmetric information

    DEFF Research Database (Denmark)

    Papakonstantinou, Athanasios; Bogetoft, Peter

    2017-01-01

    and to honestly report quality-cost probabilistic estimates based on which the principal can choose the agent that offers the best value for money. The mechanism extends second score auction design to settings where the quality is uncertain and it provides incentives to both collect information and deliver...

  3. Active fault diagnosis in closed-loop uncertain systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik

    2006-01-01

    Fault diagnosis of parametric faults in closed-loop uncertain systems by using an auxiliary input vector is considered in this paper, i.e. active fault diagnosis (AFD). The active fault diagnosis is based directly on the socalled fault signature matrix, related to the YJBK (Youla, Jabr, Bongiorno...

  4. Robust solutions of optimization problems affected by uncertain probabilities

    NARCIS (Netherlands)

    Ben-Tal, A.; den Hertog, D.; De Waegenaere, A.M.B.; Melenberg, B.; Rennen, G.

    2013-01-01

    In this paper we focus on robust linear optimization problems with uncertainty regions defined by φ-divergences (for example, chi-squared, Hellinger, Kullback–Leibler). We show how uncertainty regions based on Φ-divergences arise in a natural way as confidence sets if the uncertain parameters

  5. R&D Collaboration with Uncertain Intellectual Property Rights

    DEFF Research Database (Denmark)

    Czarnitzki, Dirk; Hussinger, Katrin; Schneider, Cédric

    2015-01-01

    uncertain intellectual property rights (IPRs) lead to reduced collaboration between firms and can, hence, hinder knowledge production. This has implications for technology policy as R&D collaborations are exempt from antitrust legislation in order to increase R&D in the economy. We argue that a functional IPR system...

  6. Airfoil Analysis with Uncertain Geometry using the Probabilistic Collocation method

    NARCIS (Netherlands)

    Loeven, G.J.A.; Bijl, H.

    2008-01-01

    Due to manufacturing tolerances, the airfoil of a wing after production is never exactly the same as the designed airfoil. Also during operation the geometry may change due to aerodynamic loading, icing or wear of the construction. The geometry can, therefore, be treated as uncertain. Uncertainties

  7. Fault tolerant control for uncertain systems with parametric faults

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2006-01-01

    A fault tolerant control (FTC) architecture based on active fault diagnosis (AFD) and the YJBK (Youla, Jarb, Bongiorno and Kucera)parameterization is applied in this paper. Based on the FTC architecture, fault tolerant control of uncertain systems with slowly varying parametric faults...

  8. How safely can post-term pregnancies with uncertain gestational ...

    African Journals Online (AJOL)

    To review whether 2 weeks' follow-up is safe for women at 42 weeks with an uncertain gestational age (GA) and amniotic fluid index (AFI) of ≥10 cm, as well as ... 5 - 10% of all pregnancies reach a gestational age. (GA) that could be considered as .... Syphilis was diagnosed in three patients, all of whom were fully treated.

  9. Numerical solution of uncertain neutron diffusion equation for ...

    Indian Academy of Sciences (India)

    Fuzzy values are handled through limit method which was defined for interval computations. The concept of fuzziness is hybridised with traditional finite element method to propose fuzzy finite element method. The proposed fuzzy finite element method has been used to obtain the uncertain eigenvalues of the said problem.

  10. Scott's Lake Excavation Letters on Human Remains

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is two letters written about the repatriation of Santee Indian human remains and funerary objects to Santee Sioux Tribe. Includes an inventory of human remains...

  11. ENU Mutagenic Screen for Susceptibility and Resistance to Streptococcus Pneumoniae

    National Research Council Canada - National Science Library

    Kindy, Mark S

    2005-01-01

    .... The genetic pathways that control susceptibility and resistance to bacterial infection have remained poorly understood, because of the lack of expertise in the development of techniques capable...

  12. Synchronization and parameter estimations of an uncertain Rikitake system

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Ibanez, Carlos, E-mail: caguilar@cic.ipn.m [CIC-IPN, Av. Juan de Dios Batiz s/n, Esq. Manuel Othon de M., Unidad Profesional Adolfo Lopez Mateos, Col. Nueva Industrial Vallejo, Del. Gustavo A. Madero, C.P. 07738, Mexico D.F. (Mexico); Martinez-Guerra, Rafael, E-mail: rguerra@ctrl.cinvestav.m [CINVESTAV-IPN, Departamento de Control Automatico, Av. Instituto Politecnico Nacional 2508, Col. San Pedro Zacatenco, Mexico, D. F., 07360 (Mexico); Aguilar-Lopez, Ricardo [CINVESTAV-IPN, Departamento de Biotecnologia y Bioingenieria (Mexico); Mata-Machuca, Juan L. [CINVESTAV-IPN, Departamento de Control Automatico, Av. Instituto Politecnico Nacional 2508, Col. San Pedro Zacatenco, Mexico, D. F., 07360 (Mexico)

    2010-08-02

    In this Letter we address the synchronization and parameter estimation of the uncertain Rikitake system, under the assumption the state is partially known. To this end we use the master/slave scheme in conjunction with the adaptive control technique. Our control approach consists of proposing a slave system which has to follow asymptotically the uncertain Rikitake system, refereed as the master system. The gains of the slave system are adjusted continually according to a convenient adaptation control law, until the measurable output errors converge to zero. The convergence analysis is carried out by using the Barbalat's Lemma. Under this context, uncertainty means that although the system structure is known, only a partial knowledge of the corresponding parameter values is available.

  13. Probabilistic Motion Planning of Balloons in Strong, Uncertain Wind Fields

    Science.gov (United States)

    Wolf, Michael T.; Blackmore, Lars; Kuwata, Yoshiaki; Fathpour, Nanaz; Elfes, Alberto; Newman, Claire

    2010-01-01

    This paper introduces a new algorithm for probabilistic motion planning in arbitrary, uncertain vector fields, with emphasis on high-level planning for Montgolfiere balloons in the atmosphere of Titan. The goal of the algorithm is to determine what altitude--and what horizontal actuation, if any is available on the vehicle--to use to reach a goal location in the fastest expected time. The winds can vary greatly at different altitudes and are strong relative to any feasible horizontal actuation, so the incorporation of the winds is critical for guidance plans. This paper focuses on how to integrate the uncertainty of the wind field into the wind model and how to reach a goal location through the uncertain wind field, using a Markov decision process (MDP). The resulting probabilistic solutions enable more robust guidance plans and more thorough analysis of potential paths than existing methods.

  14. Alcohol stress response dampening during imminent versus distal, uncertain threat.

    Science.gov (United States)

    Hefner, Kathryn R; Moberg, Christine A; Hachiya, Laura Y; Curtin, John J

    2013-08-01

    Research indicates that fear and anxiety are distinct processes with separable neurobiological substrates. Predictable versus unpredictable shock administration has been used to elicit fear versus anxiety, respectively. Recent research has demonstrated that alcohol may reduce anxiety but not fear. However, previous manipulations of predictability have varied both probability and temporal uncertainty of shock threat, leaving unresolved questions regarding which stimulus characteristics elicit anxiety and are sensitive to alcohol stress-response dampening (SRD). We developed a novel paradigm to closely parallel basic research in animals that systematically varied temporal uncertainty of threat while holding threat probability constant. Intoxicated (0.08% target blood alcohol concentration), placebo, and no-alcohol control participants viewed a series of visual threat cues. Certain cue duration (5 s) blocks were equivalent to predictable shock blocks eliciting fear in earlier research. Uncertain cue duration (5, 20, 50, or 80 s, intermixed) blocks introduced temporal uncertainty regarding impending shock to elicit anxiety. Startle potentiation relative to matched cue periods in no-shock blocks provided the primary measure of affective response. All threat cues produced robust startle potentiation. Alcohol reduced startle potentiation during the first 5 s of threat cue presentation in uncertain but not certain duration blocks. Alcohol also reduced startle potentiation at later times among longer uncertain duration cues, suggesting that alcohol SRD persisted. Trait negative emotionality and binge drinking status moderated alcohol SRD magnitude during uncertain threat. These translational findings corroborate previous reports regarding distinct substrates of fear versus anxiety and have implications for both alcoholism etiology and comorbidity with anxiety disorders. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  15. Uncertain CERN cash means UK physicists face grant freeze.

    CERN Multimedia

    1996-01-01

    Britain's funding agency Particle Physics and Astronomy Research Council is uncertain about its ability to cover membership costs to the European Laboratory for Particle Physics (CERN). This has resulted in suspension of research grants to university physicists and astronomers. Funding will be available only for genuine hardship, and for major national and international astronomical projects that have already been sanctioned. The new four-year rolling grants to university-based particle physics group is withheld.

  16. Density Estimation in Several Populations With Uncertain Population Membership

    KAUST Repository

    Ma, Yanyuan

    2011-09-01

    We devise methods to estimate probability density functions of several populations using observations with uncertain population membership, meaning from which population an observation comes is unknown. The probability of an observation being sampled from any given population can be calculated. We develop general estimation procedures and bandwidth selection methods for our setting. We establish large-sample properties and study finite-sample performance using simulation studies. We illustrate our methods with data from a nutrition study.

  17. Uncertain Spaces: Virtual Configurations in Contemporary Art and Museums

    OpenAIRE

    Barranha, Helena; Susana S. Martins; Bounia, Alexandra; Myrivili, Eleni; Dekker, Annet; Beiguelman, Giselle; Brooks, Andrew Vaas; Meschede, Sören; Kogler, Stefanie; Reitstätter, Luise; Bettel, Florian; Terracciano, Roberto; Sousa, Catarina Carneiro de; Eustáquio, Luís

    2015-01-01

    Contém artigos apresentados na International Conference “Uncertain Spaces: Virtual Configurations in Contemporary Art and Museums”, na Fundação Calouste Gulbenkian (Lisboa), 31 Outubro - 1 de Novembro de 2014) de: Helena Barranha e Susana S. Martins - Introduction: Art, Museums and Uncertainty (pp.1-12); Alexandra Bounia e Eleni Myrivili - Beyond the ‘Virtual’: Intangible Museographies and Collaborative Museum Experiences (pp.15-32); Annet Dekker - Curating in Progress. Moving Between Obje...

  18. Distributed control systems with incomplete and uncertain information

    Science.gov (United States)

    Tang, Jingpeng

    Scientific and engineering advances in wireless communication, sensors, propulsion, and other areas are rapidly making it possible to develop unmanned air vehicles (UAVs) with sophisticated capabilities. UAVs have come to the forefront as tools for airborne reconnaissance to search for, detect, and destroy enemy targets in relatively complex environments. They potentially reduce risk to human life, are cost effective, and are superior to manned aircraft for certain types of missions. It is desirable for UAVs to have a high level of intelligent autonomy to carry out mission tasks with little external supervision and control. This raises important issues involving tradeoffs between centralized control and the associated potential to optimize mission plans, and decentralized control with great robustness and the potential to adapt to changing conditions. UAV capabilities have been extended several ways through armament (e.g., Hellfire missiles on Predator UAVs), increased endurance and altitude (e.g., Global Hawk), and greater autonomy. Some known barriers to full-scale implementation of UAVs are increased communication and control requirements as well as increased platform and system complexity. One of the key problems is how UAV systems can handle incomplete and uncertain information in dynamic environments. Especially when the system is composed of heterogeneous and distributed UAVs, the overall system complexity is increased under such conditions. Presented through the use of published papers, this dissertation lays the groundwork for the study of methodologies for handling incomplete and uncertain information for distributed control systems. An agent-based simulation framework is built to investigate mathematical approaches (optimization) and emergent intelligence approaches. The first paper provides a mathematical approach for systems of UAVs to handle incomplete and uncertain information. The second paper describes an emergent intelligence approach for UAVs

  19. Airline Overbooking Problem with Uncertain No-Shows

    Directory of Open Access Journals (Sweden)

    Chunxiao Zhang

    2014-01-01

    Full Text Available This paper considers an airline overbooking problem of a new single-leg flight with discount fare. Due to the absence of historical data of no-shows for a new flight, and various uncertain human behaviors or unexpected events which causes that a few passengers cannot board their aircraft on time, we fail to obtain the probability distribution of no-shows. In this case, the airlines have to invite some domain experts to provide belief degree of no-shows to estimate its distribution. However, human beings often overestimate unlikely events, which makes the variance of belief degree much greater than that of the frequency. If we still regard the belief degree as a subjective probability, the derived results will exceed our expectations. In order to deal with this uncertainty, the number of no-shows of new flight is assumed to be an uncertain variable in this paper. Given the chance constraint of social reputation, an overbooking model with discount fares is developed to maximize the profit rate based on uncertain programming theory. Finally, the analytic expression of the optimal booking limit is obtained through a numerical example, and the results of sensitivity analysis indicate that the optimal booking limit is affected by flight capacity, discount, confidence level, and parameters of the uncertainty distribution significantly.

  20. Path planning in uncertain flow fields using ensemble method

    Science.gov (United States)

    Wang, Tong; Le Maître, Olivier P.; Hoteit, Ibrahim; Knio, Omar M.

    2016-10-01

    An ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.

  1. Path planning in uncertain flow fields using ensemble method

    KAUST Repository

    Wang, Tong

    2016-08-20

    An ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.

  2. Fuzzy Adaptive Compensation Control of Uncertain Stochastic Nonlinear Systems With Actuator Failures and Input Hysteresis.

    Science.gov (United States)

    Wang, Jianhui; Liu, Zhi; Chen, C L Philip; Zhang, Yun

    2017-10-12

    Hysteresis exists ubiquitously in physical actuators. Besides, actuator failures/faults may also occur in practice. Both effects would deteriorate the transient tracking performance, and even trigger instability. In this paper, we consider the problem of compensating for actuator failures and input hysteresis by proposing a fuzzy control scheme for stochastic nonlinear systems. Compared with the existing research on stochastic nonlinear uncertain systems, it is found that how to guarantee a prescribed transient tracking performance when taking into account actuator failures and hysteresis simultaneously also remains to be answered. Our proposed control scheme is designed on the basis of the fuzzy logic system and backstepping techniques for this purpose. It is proven that all the signals remain bounded and the tracking error is ensured to be within a preestablished bound with the failures of hysteretic actuator. Finally, simulations are provided to illustrate the effectiveness of the obtained theoretical results.

  3. Mammalian Remains from Indian Sites on Aruba

    NARCIS (Netherlands)

    Hooijer, D.A.

    1960-01-01

    Mr. H. R. VAN HEEKEREN and Mr. C. J. DU RY, of the Rijksmuseum voor Volkenkunde at Leiden, entrusted me with the identification of some animal remains collected from Indian sites on Aruba by Professor J. P. B. DE JOSSELIN DE JONG in 1923. These remains relate for the most part to marine turtles

  4. Luminescence of thermally altered human skeletal remains

    NARCIS (Netherlands)

    Krap, Tristan; Nota, Kevin; Wilk, Leah; van de Goot, Frank; Ruijter, Jan; Duijst, Wilma; Oostra, Roelof Jan

    2017-01-01

    Literature on luminescent properties of thermally altered human remains is scarce and contradictory. Therefore, the luminescence of heated bone was systemically reinvestigated. A heating experiment was conducted on fresh human bone, in two different media, and cremated human remains were recovered

  5. EDITORIAL MALARIA DIAGNOSIS Malaria remains the most ...

    African Journals Online (AJOL)

    hi-tech

    2005-03-02

    Mar 2, 2005 ... Malaria remains the most significant parasitic disease affecting man. Prompt and accurate diagnosis of malaria is the key to cost effective management (1). Since the identification of Plasmodium parasites in human blood in 1880, the diagnosis of malaria has remained a hot bed of scientific discussion.

  6. Remaining Life Expectancy With and Without Polypharmacy

    DEFF Research Database (Denmark)

    Wastesson, Jonas W; Canudas-Romo, Vladimir; Lindahl-Jacobsen, Rune

    2016-01-01

    OBJECTIVES: To investigate the remaining life expectancy with and without polypharmacy for Swedish women and men aged 65 years and older. DESIGN: Age-specific prevalence of polypharmacy from the nationwide Swedish Prescribed Drug Register (SPDR) combined with life tables from Statistics Sweden...... was used to calculate the survival function and remaining life expectancy with and without polypharmacy according to the Sullivan method. SETTING: Nationwide register-based study. PARTICIPANTS: A total of 1,347,564 individuals aged 65 years and older who had been prescribed and dispensed a drug from July 1...... to September 30, 2008. MEASUREMENTS: Polypharmacy was defined as the concurrent use of 5 or more drugs. RESULTS: At age 65 years, approximately 8 years of the 20 remaining years of life (41%) can be expected to be lived with polypharmacy. More than half of the remaining life expectancy will be spent...

  7. Mass Remaining During Evaporation of Sessile Drop

    Science.gov (United States)

    2008-09-01

    oscillations in the mass remaining. • TRANSFORM ED t TRUEt TRUEtCont 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 TIMI (Hr) Figure 13. Effect of 3 min...2.5 2.55 2.8 TIMI (Hr) 2.86 2.1 275 2.8 Figure 14. Mass Remaining vs. Time Expanded Scale The assumed sinusoidal variation of the friction velocity

  8. Effects of Working Memory Load on Uncertain Decision-making: Evidence from the Iowa Gambling Task

    Directory of Open Access Journals (Sweden)

    Ji-fang eCui

    2015-02-01

    Full Text Available The Iowa Gambling Task (IGT simulates uncertain gains and losses in real life situations and thus is a good measure of uncertain decision making. The role of working memory (WM in IGT performance still remains unclear. The present study aimed to examine the effect of WM on IGT performance. Three groups of participants matched on gender ratio were randomly assigned to no WM load, low WM load, and high WM load conditions. Initially the three groups did not show significant difference in WM capacity. They finished a modified version of IGT and then their implicit learning effect and explicit cognition on IGT were assessed. Results indicated a linear increasing trend of IGT performance among high WM load, low WM load and no WM load groups; participants in the no WM load and low WM load groups revealed implicit learning effect, while participants in the high WM load group did not; all participants showed explicit cognition on IGT to the same level. These results suggested that participants in the high WM load group showed good explicit cognition to IGT but showed poor performance. This pattern is similar to frontal patients. Further studies should be conducted to explore this issue.

  9. Effects of working memory load on uncertain decision-making: evidence from the Iowa Gambling Task.

    Science.gov (United States)

    Cui, Ji-Fang; Wang, Ya; Shi, Hai-Song; Liu, Lu-Lu; Chen, Xing-Jie; Chen, Ying-He

    2015-01-01

    The Iowa Gambling Task (IGT) simulates uncertain gains and losses in real life situations and thus is a good measure of uncertain decision-making. The role of working memory (WM) in IGT performance still remains unclear. The present study aimed to examine the effect of WM on IGT performance. Three groups of participants matched on gender ratio were randomly assigned to no WM load, low WM load, and high WM load conditions. Initially the three groups did not show significant difference in WM capacity. They finished a modified version of IGT and then their implicit learning effect and explicit cognition on IGT were assessed. Results indicated a linear increasing trend of IGT performance among high WM load, low WM load and no WM load groups; participants in the no WM load and low WM load groups revealed implicit learning effect, while participants in the high WM load group did not; all participants showed explicit cognition on IGT to the same level. These results suggested that participants in the high WM load group showed good explicit cognition to IGT but showed poor performance. This pattern is similar to frontal patients. Further studies should be conducted to explore this issue.

  10. T-S Fuzzy Control of Uncertain Chaotic Vibration

    Directory of Open Access Journals (Sweden)

    Abdelkrim Boukabou

    2012-01-01

    Full Text Available We present in this paper a novel and unified control approach that combines intelligent fuzzy logic methodology with predictive method for controlling chaotic vibration of a class of uncertain chaotic systems. We first introduce prediction into each subsystem of Takagi Sugeno (T-S fuzzy IF-THEN rules and then present a unified T-S predictive fuzzy model for chaos control. The proposed controller can successfully stabilize the chaos and track the desired targets. The simulation results illustrate its effectiveness.

  11. Uncertain Dynamics, Correlation Effects, and Robust Investment Decisions

    DEFF Research Database (Denmark)

    Flor, Christian Riis; Hesel, Søren

    2015-01-01

    We analyze a firm's investment problem when the dynamics of project value and investment cost are uncertain. We provide an explicit solution using a robust method for an ambiguity averse firm taking this into account. Ambiguity aversion regarding a common risk factor impacts differently than...... ambiguity aversion regarding investment cost residual risk. Correlation between project value and investment cost matters; ambiguity aversion regarding common risk can decrease the investment probability only if correlation is positive. Ambiguity aversion regarding residual risk always increases...... the investment probability. When only project value is risky, volatility can monotonically decrease the investment threshold; this does not hold with the multiple prior method....

  12. When, not if: The inescapability of an uncertain future

    Science.gov (United States)

    Lewandowsky, S.; Ballard, T.

    2014-12-01

    Uncertainty is an inherent feature of most scientific endeavours, and many political decisions must be made in the presence of scientific uncertainty. In the case of climate change, there is evidence that greater scientific uncertainty increases the risk associated with the impact of climate change. Scientific uncertainty thus provides an impetus for cutting emissions rather than delaying action. In contrast to those normative considerations, uncertainty is frequently cited in political and public discourse as a reason to delay mitigation. We examine ways in which this gap between public and scientific understanding of uncertainty can be bridged. In particular, we sought ways to communicate uncertainty in a way that better calibrates people's risk perceptions with the projected impact of climate change. We report two behavioural experiments in which uncertainty about the future was expressed either as outcome uncertainty or temporal uncertainty. The conventional presentation of uncertainty involves uncertainty about an outcome at a given time—for example, the range of possible sea level rise (say 50cm +/- 20cm) by a certain date. An alternative presentation of the same situation presents a certain outcome ("sea levels will rise by 50cm") but places the uncertainty into the time of arrival ("this may occur as early as 2040 or as late as 2080"). We presented participants with a series of statements and graphs indicating projected increases in temperature, sea levels, ocean acidification, and a decrease in artic sea ice. In the uncertain magnitude condition, the statements and graphs reported the upper and lower confidence bounds of the projected magnitude and the mean projected time of arrival. In the uncertain time of arrival condition, they reported the upper and lower confidence bounds of the projected time of arrival and the mean projected magnitude. The results show that when uncertainty was presented as uncertain time of arrival rather than an uncertain

  13. Fuzzy controller for a system with uncertain load

    DEFF Research Database (Denmark)

    Kulczycki, P.; Wisniewski, Rafal

    2002-01-01

    In many applications of motion control, problems associated with imprecisely measured or changing load (a mass or a moment of inertia) can be a serious obstacle in the formation of satisfactory controlling systems. This barrier compels the designer to include various kinds of uncertainties...... in engineering solutions. The present paper deals with the time-optimal control for mechanical systems with uncertain load. A fuzzy approach is used in the design of suboptimal feedback controllers, robust with respect to the load. The methodology proposed in this work may be easily adapted to other modeling...... uncertainties of mechanical systems, e.g. parameters of drive or motion resistance....

  14. 75 FR 54802 - Requirement of a Statement Disclosing Uncertain Tax Positions

    Science.gov (United States)

    2010-09-09

    ... for audit and expend a substantial amount of effort by revenue agents to determine what uncertain tax... Internal Revenue Service 26 CFR Part 1 RIN 1545-BJ54 Requirement of a Statement Disclosing Uncertain Tax... corporations to file a schedule disclosing uncertain tax positions related to the tax return as required by the...

  15. High Frequency of Interactions between Lung Cancer Susceptibility Genes in the Mouse : Mapping of Sluc5 to Sluc14

    NARCIS (Netherlands)

    Fijneman, Remond J.A.; Jansen, Ritsert C.; Valk, Martin A. van der; Demant, Peter

    1998-01-01

    Although several genes that cause monogenic familial cancer syndromes have been identified, susceptibility to sporadic cancer remains unresolved. Animal experiments have demonstrated multigenic control of tumor susceptibility. Recently, we described four mouse lung cancer susceptibility (Sluc) loci,

  16. Fault Diagnosis of Nonlinear Uncertain Systems with Triangular Form

    Directory of Open Access Journals (Sweden)

    Qi Ding

    2017-01-01

    Full Text Available A novel approach to fault diagnosis for a class of nonlinear uncertain systems with triangular form is proposed in this paper. It is based on the extended state observer (ESO of the active disturbance rejection controller and linearization of dynamic compensation. Firstly, an ESO is designed to jointly estimate the states and the combination of uncertainty, faults, and nonlinear function of nonlinear uncertain systems. It can derive the estimation of nonlinear function via the state estimations and system model. Then, linearization of dynamic compensation is employed to linearize the system by offsetting nonlinear function mandatorily using its estimation. An observer-based residual generator is designed on the basis of the prior linearized model for fault diagnosis. Moreover, threshold treatment technique is adopted to improve the robustness of fault diagnosis. This method is utilizable and simple in construction and parameter tuning. And also we show the construction of ESO and give the corresponding convergence proof succinctly. Finally, a numerical example is presented to illustrate the validity of the proposed fault diagnosis scheme.

  17. Global sensitivity analysis in stochastic simulators of uncertain reaction networks

    KAUST Repository

    Navarro, María

    2016-12-26

    Stochastic models of chemical systems are often subjected to uncertainties in kinetic parameters in addition to the inherent random nature of their dynamics. Uncertainty quantification in such systems is generally achieved by means of sensitivity analyses in which one characterizes the variability with the uncertain kinetic parameters of the first statistical moments of model predictions. In this work, we propose an original global sensitivity analysis method where the parametric and inherent variability sources are both treated through Sobol’s decomposition of the variance into contributions from arbitrary subset of uncertain parameters and stochastic reaction channels. The conceptual development only assumes that the inherent and parametric sources are independent, and considers the Poisson processes in the random-time-change representation of the state dynamics as the fundamental objects governing the inherent stochasticity. A sampling algorithm is proposed to perform the global sensitivity analysis, and to estimate the partial variances and sensitivity indices characterizing the importance of the various sources of variability and their interactions. The birth-death and Schlögl models are used to illustrate both the implementation of the algorithm and the richness of the proposed analysis method. The output of the proposed sensitivity analysis is also contrasted with a local derivative-based sensitivity analysis method classically used for this type of systems.

  18. On the robust optimization to the uncertain vaccination strategy problem

    Energy Technology Data Exchange (ETDEWEB)

    Chaerani, D., E-mail: d.chaerani@unpad.ac.id; Anggriani, N., E-mail: d.chaerani@unpad.ac.id; Firdaniza, E-mail: d.chaerani@unpad.ac.id [Department of Mathematics, Faculty of Mathematics and Natural Sciences, University of Padjadjaran Indonesia, Jalan Raya Bandung Sumedang KM 21 Jatinangor Sumedang 45363 (Indonesia)

    2014-02-21

    In order to prevent an epidemic of infectious diseases, the vaccination coverage needs to be minimized and also the basic reproduction number needs to be maintained below 1. This means that as we get the vaccination coverage as minimum as possible, thus we need to prevent the epidemic to a small number of people who already get infected. In this paper, we discuss the case of vaccination strategy in term of minimizing vaccination coverage, when the basic reproduction number is assumed as an uncertain parameter that lies between 0 and 1. We refer to the linear optimization model for vaccination strategy that propose by Becker and Starrzak (see [2]). Assuming that there is parameter uncertainty involved, we can see Tanner et al (see [9]) who propose the optimal solution of the problem using stochastic programming. In this paper we discuss an alternative way of optimizing the uncertain vaccination strategy using Robust Optimization (see [3]). In this approach we assume that the parameter uncertainty lies within an ellipsoidal uncertainty set such that we can claim that the obtained result will be achieved in a polynomial time algorithm (as it is guaranteed by the RO methodology). The robust counterpart model is presented.

  19. Intelligent diagnosis of jaundice with dynamic uncertain causality graph model.

    Science.gov (United States)

    Hao, Shao-Rui; Geng, Shi-Chao; Fan, Lin-Xiao; Chen, Jia-Jia; Zhang, Qin; Li, Lan-Juan

    2017-05-01

    Jaundice is a common and complex clinical symptom potentially occurring in hepatology, general surgery, pediatrics, infectious diseases, gynecology, and obstetrics, and it is fairly difficult to distinguish the cause of jaundice in clinical practice, especially for general practitioners in less developed regions. With collaboration between physicians and artificial intelligence engineers, a comprehensive knowledge base relevant to jaundice was created based on demographic information, symptoms, physical signs, laboratory tests, imaging diagnosis, medical histories, and risk factors. Then a diagnostic modeling and reasoning system using the dynamic uncertain causality graph was proposed. A modularized modeling scheme was presented to reduce the complexity of model construction, providing multiple perspectives and arbitrary granularity for disease causality representations. A "chaining" inference algorithm and weighted logic operation mechanism were employed to guarantee the exactness and efficiency of diagnostic reasoning under situations of incomplete and uncertain information. Moreover, the causal interactions among diseases and symptoms intuitively demonstrated the reasoning process in a graphical manner. Verification was performed using 203 randomly pooled clinical cases, and the accuracy was 99.01% and 84.73%, respectively, with or without laboratory tests in the model. The solutions were more explicable and convincing than common methods such as Bayesian Networks, further increasing the objectivity of clinical decision-making. The promising results indicated that our model could be potentially used in intelligent diagnosis and help decrease public health expenditure.

  20. Fish remains and humankind: part two

    Directory of Open Access Journals (Sweden)

    Andrew K G Jones

    1998-07-01

    Full Text Available The significance of aquatic resources to past human groups is not adequately reflected in the published literature - a deficiency which is gradually being acknowledged by the archaeological community world-wide. The publication of the following three papers goes some way to redress this problem. Originally presented at an International Council of Archaeozoology (ICAZ Fish Remains Working Group meeting in York, U.K. in 1987, these papers offer clear evidence of the range of interest in ancient fish remains across the world. Further papers from the York meeting were published in Internet Archaeology 3 in 1997.

  1. Implementation of the European multicentre database of healthy controls for [(123)I]FP-CIT SPECT increases diagnostic accuracy in patients with clinically uncertain parkinsonian syndromes

    DEFF Research Database (Denmark)

    Albert, Nathalie L; Unterrainer, Marcus; Diemling, Markus

    2016-01-01

    PURPOSE: Even though [(123)I]FP-CIT SPECT provides high accuracy in detecting nigrostriatal cell loss in neurodegenerative parkinsonian syndromes (PS), some patients with an inconclusive diagnosis remain. We investigated whether the diagnostic accuracy in patients with clinically uncertain PS wit...

  2. Adaptive Output-Feedback Neural Control of Switched Uncertain Nonlinear Systems With Average Dwell Time.

    Science.gov (United States)

    Long, Lijun; Zhao, Jun

    2015-07-01

    This paper investigates the problem of adaptive neural tracking control via output-feedback for a class of switched uncertain nonlinear systems without the measurements of the system states. The unknown control signals are approximated directly by neural networks. A novel adaptive neural control technique for the problem studied is set up by exploiting the average dwell time method and backstepping. A switched filter and different update laws are designed to reduce the conservativeness caused by adoption of a common observer and a common update law for all subsystems. The proposed controllers of subsystems guarantee that all closed-loop signals remain bounded under a class of switching signals with average dwell time, while the output tracking error converges to a small neighborhood of the origin. As an application of the proposed design method, adaptive output feedback neural tracking controllers for a mass-spring-damper system are constructed.

  3. The annuity puzzle remains a puzzle

    NARCIS (Netherlands)

    Peijnenburg, Kim; Nijman, Theo; Werker, Bas J. M.

    We examine incomplete annuity menus, background risk, bequest motives, and default risk as possible drivers of divergence from full annuitization. Contrary to what is often suggested in the literature, we find that full annuitization remains optimal if saving is possible after retirement. This holds

  4. Predicting the remaining service life of concrete

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, J.F.

    1991-11-01

    Nuclear power plants are providing, currently, about 17 percent of the U.S. electricity and many of these plants are approaching their licensed life of 40 years. The U.S. Nuclear Regulatory Commission and the Department of Energy`s Oak Ridge National Laboratory are carrying out a program to develop a methodology for assessing the remaining safe-life of the concrete components and structures in nuclear power plants. This program has the overall objective of identifying potential structural safety issues, as well as acceptance criteria, for use in evaluations of nuclear power plants for continued service. The National Institute of Standards and Technology (NIST) is contributing to this program by identifying and analyzing methods for predicting the remaining life of in-service concrete materials. This report examines the basis for predicting the remaining service lives of concrete materials of nuclear power facilities. Methods for predicting the service life of new and in-service concrete materials are analyzed. These methods include (1) estimates based on experience, (2) comparison of performance, (3) accelerated testing, (4) stochastic methods, and (5) mathematical modeling. New approaches for predicting the remaining service lives of concrete materials are proposed and recommendations for their further development given. Degradation processes are discussed based on considerations of their mechanisms, likelihood of occurrence, manifestations, and detection. They include corrosion, sulfate attack, alkali-aggregate reactions, frost attack, leaching, radiation, salt crystallization, and microbiological attack.

  5. The case for fencing remains intact.

    Science.gov (United States)

    Packer, C; Swanson, A; Canney, S; Loveridge, A; Garnett, S; Pfeifer, M; Burton, A C; Bauer, H; MacNulty, D

    2013-11-01

    Creel et al. argue against the conservation effectiveness of fencing based on a population measure that ignores the importance of top predators to ecosystem processes. Their statistical analyses consider, first, only a subset of fenced reserves and, second, an incomplete examination of 'costs per lion.' Our original conclusions remain unaltered. © 2013 John Wiley & Sons Ltd/CNRS.

  6. Kadav Moun PSA (:60) (Human Remains)

    Centers for Disease Control (CDC) Podcasts

    2010-02-18

    This is an important public health announcement about safety precautions for those handling human remains. Language: Haitian Creole.  Created: 2/18/2010 by Centers for Disease Control and Prevention (CDC).   Date Released: 2/18/2010.

  7. Juveniles' Motivations for Remaining in Prostitution

    Science.gov (United States)

    Hwang, Shu-Ling; Bedford, Olwen

    2004-01-01

    Qualitative data from in-depth interviews were collected in 1990-1991, 1992, and 2000 with 49 prostituted juveniles remanded to two rehabilitation centers in Taiwan. These data are analyzed to explore Taiwanese prostituted juveniles' feelings about themselves and their work, their motivations for remaining in prostitution, and their difficulties…

  8. Modeling heat exchangers under consideration of manufacturing tolerances and uncertain flow distribution

    Energy Technology Data Exchange (ETDEWEB)

    Abdelaziz, O.; Radermacher, R. [Center for Environmental Energy Engineering, Department of Mechanical Engineering, University of Maryland, 4164 Martin Hall, College Park, MD 20742 (United States)

    2010-06-15

    Small dimensions found in modern and novel heat exchanger (HX) designs encounter very challenging manufacturing issues. With current manufacturing techniques HXs in small dimensions will exhibit large tolerances relative to design variables. Hence, the anticipated variation in performance is a concern. Furthermore, small flow channel dimensions are very susceptible to severe fouling and even blockage. Therefore, flow distribution would be uncertain. These uncertainties in dimensions and flow distribution should be accounted for during the design and performance evaluation of new HX geometries with focus on ultra-compact designs. This paper outlines an effort to theoretically evaluate the performance of an air-to-water HX, assembled from tubes with non-conventional heat transfer surfaces. Vertical spacing within this HX is subject to a predefined statistical distribution compounded with uncertainty in water flow rate through each flow path (i.e., tube). A new implementation technique for {epsilon}-NTU is proposed in order to accommodate different air conditions on both tube sides. A Monte Carlo simulation approach is used to estimate the HX performance distribution. This approach is applied to three HX designs showing the performance degradation subject to geometrical and flow uncertainties. The simulation results under uncertainty provided useful insights into the reasons for the performance degradation and showed great impact to the uncertainty distribution. Overall, the proposed HX design with the smallest dimensions showed the least performance degradation due to manufacturing and operating conditions uncertainty. (author)

  9. Classification and Clinical Management of Variants of Uncertain Significance in High Penetrance Cancer Predisposition Genes.

    Science.gov (United States)

    Moghadasi, Setareh; Eccles, Diana M; Devilee, Peter; Vreeswijk, Maaike P G; van Asperen, Christi J

    2016-04-01

    In 2008, the International Agency for Research on Cancer (IARC) proposed a system for classifying sequence variants in highly penetrant breast and colon cancer susceptibility genes, linked to clinical actions. This system uses a multifactorial likelihood model to calculate the posterior probability that an altered DNA sequence is pathogenic. Variants between 5%-94.9% (class 3) are categorized as variants of uncertain significance (VUS). This interval is wide and might include variants with a substantial difference in pathogenicity at either end of the spectrum. We think that carriers of class 3 variants would benefit from a fine-tuning of this classification. Classification of VUS to a category with a defined clinical significance is very important because for carriers of a pathogenic mutation full surveillance and risk-reducing surgery can reduce cancer incidence. Counselees who are not carriers of a pathogenic mutation can be discharged from intensive follow-up and avoid unnecessary risk-reducing surgery. By means of examples, we show how, in selected cases, additional data can lead to reclassification of some variants to a different class with different recommendations for surveillance and therapy. To improve the clinical utility of this classification system, we suggest a pragmatic adaptation to clinical practice. © 2016 WILEY PERIODICALS, INC.

  10. Social expectations bias decision-making in uncertain inter-personal situations.

    Directory of Open Access Journals (Sweden)

    María Ruz

    Full Text Available Understanding the role that social cues have on interpersonal choice, and their susceptibility to contextual effects, is of core importance to models of social decision-making. Language, on the other hand, is one of the main means of communication during social interactions in our culture. The present experiments tested whether positive and negative linguistic descriptions of alleged partners in a modified Ultimatum Game biased decisions made to the same set of offers, and whether the contextual uncertainty of the game modulated this biasing effect. The results showed that in an uncertain context, the same offers were accepted with higher probability when they were preceded by positive rather than by negative valenced trait-words. Participants also accepted fair offers with higher probability than unfair offers, but this effect did not interact with the valence of the social descriptive words. In addition, the speed of the decision was affected by valence: acceptance choices were faster when they followed a positive adjective, whereas rejection responses were faster after a negative-valenced word. However, these effects were highly reduced when the uncertainty was eliminated from the game. This suggests that positive and negative relevant social information can bias decisions made to the same pieces of evidence during interpersonal interactions, but that this mainly takes place when the uncertainty associated with the choices is high.

  11. [Remaining solvents in dry cleaned over clothes].

    Science.gov (United States)

    Tashiro, H; Fujishiro, K; Matsuno, K; Kawamoto, T; Okubo, T

    1999-03-01

    We examined remaining solvents in dry cleaned trousers to estimate the magnitude of environmental pollution. A cleaning solvent of petroleum hydrocarbon was analyzed by means of capillary column mass spectrum gas chromatography. Principal ingredients were identified to be nonane, decane and undecane. The same main components were detected in dry cleaned trousers. Total amounts of evaporated vapor from a pair of trousers (480 g) in 5 days after dry cleaning were nonane (0.73 mg), decane (1.53 mg) and undecane (1.09 mg). The levels on the fifth day were 5%(nonane), 18%(decane) and 32%(undecane) of the first day's concentration, respectively. The half times of the remaining solvents were 1.0 day (nonane), 1.7 days (decane) and 2.7 days (undecane), respectively.

  12. SMART POINT CLOUD: DEFINITION AND REMAINING CHALLENGES

    OpenAIRE

    Poux, Florent; Neuville, Romain; Hallot, Pierre; Billen, Roland

    2016-01-01

    Dealing with coloured point cloud acquired from terrestrial laser scanner, this paper identifies remaining challenges for a new data structure: the smart point cloud. This concept arises with the statement that massive and discretized spatial information from active remote sensing technology is often underused due to data mining limitations. The generalisation of point cloud data associated with the heterogeneity and temporality of such datasets is the main issue regarding structure, segmenta...

  13. [Professional confidentiality: speak out or remain silent? ].

    Science.gov (United States)

    Daubigney, Jean-claude

    2014-01-01

    People who work with children, in their daily tasks, must choose whether to disclose information entrusted to them. However, they are subject to the law, which authorises or imposes speaking out or remaining silent. In terms of ethics, they can seek the best possible response while respecting professional secrecy when meeting an individual, in a situation, in a place or at a particular time. They must then take responsibility for that decision.

  14. Structured controllers for uncertain systems a stochastic optimization approach

    CERN Document Server

    Toscano, Rosario

    2013-01-01

    Structured Controllers for Uncertain Systems focuses on the development of easy-to-use design strategies for robust low-order or fixed-structure controllers (particularly the industrially ubiquitous PID controller). These strategies are based on a recently-developed stochastic optimization method termed the "Heuristic Kalman Algorithm" (HKA) the use of which results in a simplified methodology that enables the solution of the structured control problem without a profusion of user-defined parameters. An overview of the main stochastic methods employable in the context of continuous non-convex optimization problems is also provided and various optimization criteria for the design of a structured controller are considered; H∞, H2, and mixed H2/H∞ each merits a chapter to itself. Time-domain-performance specifications can be easily incorporated in the design. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technolo...

  15. Model Predictive Control of Wind Turbines using Uncertain LIDAR Measurements

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood; Soltani, Mohsen; Poulsen, Niels Kjølstad

    2013-01-01

    The problem of Model predictive control (MPC) of wind turbines using uncertain LIDAR (LIght Detection And Ranging) measurements is considered. A nonlinear dynamical model of the wind turbine is obtained. We linearize the obtained nonlinear model for different operating points, which are determined...... by the effective wind speed on the rotor disc. We take the wind speed as a scheduling variable. The wind speed is measurable ahead of the turbine using LIDARs, therefore, the scheduling variable is known for the entire prediction horizon. By taking the advantage of having future values of the scheduling variable...... on wind speed estimation and measurements from the LIDAR is devised to find an estimate of the delay and compensate for it before it is used in the controller. Comparisons between the MPC with error compensation, the MPC without error compensation and an MPC with re-linearization at each sample point...

  16. Wind turbine control and model predictive control for uncertain systems

    DEFF Research Database (Denmark)

    Thomsen, Sven Creutz

    This thesis presents both an applied study and a theoretical study within the field of control theory. Control theory is an interdisciplinary branch between mathematics and engineering dealing with the manipulation of systems to produce a desired output. The applied study deals with wind turbine...... as disturbance models for controller design. The theoretical study deals with Model Predictive Control (MPC). MPC is an optimal control method which is characterized by the use of a receding prediction horizon. MPC has risen in popularity due to its inherent ability to systematically account for time......-domain constraints on signals. During the last decades several theoretical advances have been made, so that it can handle a wide variety of system structures. In this thesis, the focus is on handling uncertain linear system description. To this end the so-called Youla parameterizations have been used. Two methods...

  17. Adaptive Fuzzy Containment Control for Uncertain Nonlinear Multiagent Systems

    Directory of Open Access Journals (Sweden)

    Yang Yu

    2014-01-01

    Full Text Available This paper considers the containment control problem for uncertain nonlinear multiagent systems under directed graphs. The followers are governed by nonlinear systems with unknown dynamics while the multiple leaders are neighbors of a subset of the followers. Fuzzy logic systems (FLSs are used to identify the unknown dynamics and a distributed state feedback containment control protocol is proposed. This result is extended to the output feedback case, where observers are designed to estimate the unmeasurable states. Then, an output feedback containment control scheme is presented. The developed state feedback and output feedback containment controllers guarantee that the states of all followers converge to the convex hull spanned by the dynamic leaders. Based on Lyapunov stability theory, it is proved that the containment control errors are uniformly ultimately bounded (UUB. An example is provided to show the effectiveness of the proposed control method.

  18. Stabilization of fractional-order singular uncertain systems.

    Science.gov (United States)

    Ji, Yude; Qiu, Jiqing

    2015-05-01

    This paper focuses on the state and static output feedback stabilization for fractional-order singular (FOS) uncertain linear systems with the fractional commensurate order 0controllers that guarantee the stability of resulting closed-loop control systems. First, the sufficient conditions for robust asymptotical stability of the closed-loop control systems are presented. Next, based on the matrix׳s singular value decomposition (SVD) and linear matrix inequality (LMI) technics, some new results in the form of LMI are developed to the state and static output feedback controller synthesis for the FOS systems. Finally, three numerical examples are given to illustrate the effectiveness of the proposed design methods. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Model Predictive Control of Wind Turbines using Uncertain LIDAR Measurements

    DEFF Research Database (Denmark)

    Mirzaei, Mahmood; Soltani, Mohsen; Poulsen, Niels Kjølstad

    2013-01-01

    The problem of Model predictive control (MPC) of wind turbines using uncertain LIDAR (LIght Detection And Ranging) measurements is considered. A nonlinear dynamical model of the wind turbine is obtained. We linearize the obtained nonlinear model for different operating points, which are determined...... by the effective wind speed on the rotor disc. We take the wind speed as a scheduling variable. The wind speed is measurable ahead of the turbine using LIDARs, therefore, the scheduling variable is known for the entire prediction horizon. By taking the advantage of having future values of the scheduling variable......, we simplify state prediction for the MPC. Consequently, the control problem of the nonlinear system is simplified into a quadratic programming. We consider uncertainty in the wind propagation time, which is the traveling time of wind from the LIDAR measurement point to the rotor. An algorithm based...

  20. Energy trading and pricing in microgrids with uncertain energy supply

    DEFF Research Database (Denmark)

    Ma, Kai; Hu, Shubing; Yang, Jie

    2017-01-01

    This paper studies an energy trading and pricing problem for microgrids with uncertain energy supply. The energy provider with the renewable energy (RE) generation (wind power) determines the energy purchase from the electricity markets and the pricing strategy for consumers to maximize its profit......, and then the consumers determine their energy demands to maximize their payoffs. The hierarchical game is established between the energy provider and the consumers. The energy provider is the leader and the consumers are the followers in the hierarchical game. We consider two types of consumers according....... In particular, the uncertainty of the energy supply from the energy provider is considered. Simulation results show that the energy provider can obtain more profit using the proposed decision-making scheme....

  1. Design of Distributed Engine Control Systems with Uncertain Delay.

    Science.gov (United States)

    Liu, Xiaofeng; Li, Yanxi; Sun, Xu

    Future gas turbine engine control systems will be based on distributed architecture, in which, the sensors and actuators will be connected to the controllers via a communication network. The performance of the distributed engine control (DEC) is dependent on the network performance. This study introduces a distributed control system architecture based on a networked cascade control system (NCCS). Typical turboshaft engine-distributed controllers are designed based on the NCCS framework with a H∞ output feedback under network-induced time delays and uncertain disturbances. The sufficient conditions for robust stability are derived via the Lyapunov stability theory and linear matrix inequality approach. Both numerical and hardware-in-loop simulations illustrate the effectiveness of the presented method.

  2. Design of Distributed Engine Control Systems with Uncertain Delay.

    Directory of Open Access Journals (Sweden)

    Xiaofeng Liu

    Full Text Available Future gas turbine engine control systems will be based on distributed architecture, in which, the sensors and actuators will be connected to the controllers via a communication network. The performance of the distributed engine control (DEC is dependent on the network performance. This study introduces a distributed control system architecture based on a networked cascade control system (NCCS. Typical turboshaft engine-distributed controllers are designed based on the NCCS framework with a H∞ output feedback under network-induced time delays and uncertain disturbances. The sufficient conditions for robust stability are derived via the Lyapunov stability theory and linear matrix inequality approach. Both numerical and hardware-in-loop simulations illustrate the effectiveness of the presented method.

  3. Multilateral Telecoordinated Control of Multiple Robots With Uncertain Kinematics.

    Science.gov (United States)

    Zhai, Di-Hua; Xia, Yuanqing

    2017-06-06

    This paper addresses the telecoordinated control of multiple robots in the simultaneous presence of asymmetric time-varying delays, nonpassive external forces, and uncertain kinematics/dynamics. To achieve the control objective, a neuroadaptive controller with utilizing prescribed performance control and switching control technique is developed, where the basic idea is to employ the concept of motion synchronization in each pair of master-slave robots and among all slave robots. By using the multiple Lyapunov-Krasovskii functionals method, the state-independent input-to-output practical stability of the closed-loop system is established. Compared with the previous approaches, the new design is straightforward and easier to implement and is applicable to a wider area. Simulation results on three pairs of three degrees-of-freedom robots confirm the theoretical findings.

  4. Switching State-Feedback LPV Control with Uncertain Scheduling Parameters

    Science.gov (United States)

    He, Tianyi; Al-Jiboory, Ali Khudhair; Swei, Sean Shan-Min; Zhu, Guoming G.

    2017-01-01

    This paper presents a new method to design Robust Switching State-Feedback Gain-Scheduling (RSSFGS) controllers for Linear Parameter Varying (LPV) systems with uncertain scheduling parameters. The domain of scheduling parameters are divided into several overlapped subregions to undergo hysteresis switching among a family of simultaneously designed LPV controllers over the corresponding subregion with the guaranteed H-infinity performance. The synthesis conditions are given in terms of Parameterized Linear Matrix Inequalities that guarantee both stability and performance at each subregion and associated switching surfaces. The switching stability is ensured by descent parameter-dependent Lyapunov function on switching surfaces. By solving the optimization problem, RSSFGS controller can be obtained for each subregion. A numerical example is given to illustrate the effectiveness of the proposed approach over the non-switching controllers.

  5. Fuzzy Backstepping Sliding Mode Control for Mismatched Uncertain System

    Directory of Open Access Journals (Sweden)

    H. Q. Hou

    2014-06-01

    Full Text Available Sliding mode controllers have succeeded in many control problems that the conventional control theories have difficulties to deal with; however it is practically impossible to achieve high-speed switching control. Therefore, in this paper an adaptive fuzzy backstepping sliding mode control scheme is derived for mismatched uncertain systems. Firstly fuzzy sliding mode controller is designed using backstepping method based on the Lyapunov function approach, which is capable of handling mismatched problem. Then fuzzy sliding mode controller is designed using T-S fuzzy model method, it can improve the performance of the control systems and their robustness. Finally this method of control is applied to nonlinear system as a case study; simulation results are also provided the performance of the proposed controller.

  6. Roe solver with entropy corrector for uncertain hyperbolic systems

    Energy Technology Data Exchange (ETDEWEB)

    Tryoen, J.; Ern, A. [Univ Paris Est, CERMICS, Ecole Ponts, F-77455 Marne La Vallee 2 (France); Tryoen, J.; Le Maitre, O. [CNRS, LIMSI, F-91403 Orsay (France); Ndjinga, M. [CEA Saclay, DEN, DM2S, SFME, F-91191 Gif Sur Yvette (France)

    2010-07-01

    This paper deals with intrusive Galerkin projection methods with a Roe-type solver for treating uncertain hyperbolic systems using a finite volume discretization in physical space and a piecewise continuous representation at the stochastic level. The aim of this paper is to design a cost-effective adaptation of the deterministic Dubois and Mehlman corrector to avoid entropy-violating shocks in the presence of sonic points. The adaptation relies on an estimate of the eigenvalues and eigenvectors of the Galerkin Jacobian matrix of the deterministic system of the stochastic modes of the solution and on a correspondence between these approximate eigenvalues and eigenvectors for the intermediate states considered at the interface. We derive some indicators that can be used to decide where a correction is needed, thereby reducing the computational costs considerably. The effectiveness of the proposed corrector is assessed on the Burgers and Euler equations including sonic points. (authors)

  7. Cooperative Control for Uncertain Multiagent Systems via Distributed Output Regulation

    Directory of Open Access Journals (Sweden)

    Lu Yu

    2013-01-01

    Full Text Available The distributed robust output regulation problem for multiagent systems is considered. For heterogeneous uncertain linear systems and a linear exosystem, the controlling aim is to stabilize the closed-loop system and meanwhile let the regulated outputs converge to the origin asymptotically, by the help of local interaction. The communication topology considered is directed acyclic graphs, which means directed graphs without loops. With distributed dynamic state feedback controller and output feedback controller, respectively, the solvability of the problem and the algorithm of controller design are both investigated. The solvability conditions are given in terms of linear matrix inequalities (LMIs. It is shown that, for polytopic uncertainties, the distributed controllers constructed by solving LMIs can satisfy the requirements of output regulation property.

  8. Distribution of albatross remains in the Far East regions during the Holocene, based on zooarchaeological remains.

    Science.gov (United States)

    Eda, Masaki; Higuchi, Hiroyoshi

    2004-07-01

    Many albatross remains have been found in the Japanese Islands and the surrounding areas, such as Sakhalin and South Korea. These remains are interesting for two reasons: numerous sites from which albatross remains have been found are located in coastal regions of the Far East where no albatrosses have been distributed recently, and there are some sites in which albatross remains represent a large portion of avian remains, although albatrosses are not easily preyed upon by human beings. We collected data on albatross remains from archaeological sites in the Far East regions during the Holocene and arranged the remains geographically, temporally and in terms of quantity. Based on these results, we showed that coastal areas along the Seas of Okhotsk and Japan have rarely been used by albatrosses in Modern times, though formerly there were many albatrosses. We proposed two explanations for the shrinkage of their distributional range: excessive hunting in the breeding areas, and distributional changes of prey for albatrosses.

  9. Shotgun microbial profiling of fossil remains

    DEFF Research Database (Denmark)

    Der Sarkissian, Clio; Ermini, Luca; Jónsson, Hákon

    2014-01-01

    Millions to billions of DNA sequences can now be generated from ancient skeletal remains thanks to the massive throughput of next-generation sequencing platforms. Except in cases of exceptional endogenous DNA preservation, most of the sequences isolated from fossil material do not originate from...... community profiling of the seven specimens revealed site-specific environmental signatures. These microbial communities appear to comprise mainly organisms that colonized the fossils recently. Our approach significantly extends the amount of useful data that can be recovered from ancient specimens using...

  10. Susceptibility to malignant hyperthermia

    NARCIS (Netherlands)

    Snoeck, Marcus Matheus Johannes

    2004-01-01

    In this thesis the author studied the diagnostic procedures for susceptibility to malignant hyperthermia (MH), with special emphasis upon refining the biological diagnostic test and improving protocols and guidelines for investigation of MH susceptibility. MH is a pharmacogenetic disease of skeletal

  11. Implementation on Electronic Circuits and RTR Pragmatical Adaptive Synchronization: Time-Reversed Uncertain Dynamical Systems' Analysis and Applications

    Directory of Open Access Journals (Sweden)

    Shih-Yu Li

    2013-01-01

    Full Text Available We expose the chaotic attractors of time-reversed nonlinear system, further implement its behavior on electronic circuit, and apply the pragmatical asymptotically stability theory to strictly prove that the adaptive synchronization of given master and slave systems with uncertain parameters can be achieved. In this paper, the variety chaotic motions of time-reversed Lorentz system are investigated through Lyapunov exponents, phase portraits, and bifurcation diagrams. For further applying the complex signal in secure communication and file encryption, we construct the circuit to show the similar chaotic signal of time-reversed Lorentz system. In addition, pragmatical asymptotically stability theorem and an assumption of equal probability for ergodic initial conditions (Ge et al., 1999, Ge and Yu, 2000, and Matsushima, 1972 are proposed to strictly prove that adaptive control can be accomplished successfully. The current scheme of adaptive control—by traditional Lyapunov stability theorem and Barbalat lemma, which are used to prove the error vector—approaches zero, as time approaches infinity. However, the core question—why the estimated or given parameters also approach to the uncertain parameters—remains without answer. By the new stability theory, those estimated parameters can be proved approaching the uncertain values strictly, and the simulation results are shown in this paper.

  12. Does hypertension remain after kidney transplantation?

    Directory of Open Access Journals (Sweden)

    Gholamreza Pourmand

    2015-05-01

    Full Text Available Hypertension is a common complication of kidney transplantation with the prevalence of 80%. Studies in adults have shown a high prevalence of hypertension (HTN in the first three months of transplantation while this rate is reduced to 50- 60% at the end of the first year. HTN remains as a major risk factor for cardiovascular diseases, lower graft survival rates and poor function of transplanted kidney in adults and children. In this retrospective study, medical records of 400 kidney transplantation patients of Sina Hospital were evaluated. Patients were followed monthly for the 1st year, every two months in the 2nd year and every three months after that. In this study 244 (61% patients were male. Mean ± SD age of recipients was 39.3 ± 13.8 years. In most patients (40.8% the cause of end-stage renal disease (ESRD was unknown followed by HTN (26.3%. A total of 166 (41.5% patients had been hypertensive before transplantation and 234 (58.5% had normal blood pressure. Among these 234 individuals, 94 (40.2% developed post-transplantation HTN. On the other hand, among 166 pre-transplant hypertensive patients, 86 patients (56.8% remained hypertensive after transplantation. Totally 180 (45% patients had post-transplantation HTN and 220 patients (55% didn't develop HTN. Based on the findings, the incidence of post-transplantation hypertension is high, and kidney transplantation does not lead to remission of hypertension. On the other hand, hypertension is one of the main causes of ESRD. Thus, early screening of hypertension can prevent kidney damage and reduce further problems in renal transplant recipients.

  13. Modeling of uncertain spectra through stochastic autoregressive systems

    Science.gov (United States)

    Wang, Yiwei; Wang, X. Q.; Mignolet, Marc P.; Yang, Shuchi; Chen, P. C.

    2016-03-01

    The focus of this investigation is on the formulation and validation of a modeling strategy of the uncertainty that may exist on the specification of the power spectral density of scalar stationary processes and on the spectral matrices of vector ones. These processes may, for example, be forces on a structure originating from natural phenomena which are coarsely modeled (i.e., with epistemic uncertainty) or are specified by parameters unknown (i.e., with aleatoric uncertainty) in the application considered. The propagation of the uncertainty, e.g., to the response of the structure, may be carried out provided that a stochastic model of the uncertainty in the power spectral density/matrix is available from which admissible samples can be efficiently generated. Such a stochastic model will be developed here through an autoregressive-based parameterization of the specified baseline power spectral density/matrix and of its random samples. Autoregressive (AR) models are particularly well suited for this parametrization since their spectra are known to converge to a broad class of spectra (all non-pathological spectra) as the AR order increases. Note that the characterization of these models is not achieved directly in terms of their coefficients but rather in terms of their reflection coefficients which lie (or their eigenvalues in the vector process case) in the domain [0,1) as a necessary and sufficient condition for stability. Maximum entropy concepts are then employed to formulate the distribution of the reflection coefficients in both scalar and vector process case leading to a small set of hyperparameters of the uncertain model. Depending on the information available, these hyperparameters could either be varied in a parametric study format to assess the effects of uncertainty or could be identified, e.g., in a maximum likelihood format, from observed data. The validation and assessment of these concepts is finally achieved on several examples including the

  14. SMART POINT CLOUD: DEFINITION AND REMAINING CHALLENGES

    Directory of Open Access Journals (Sweden)

    F. Poux

    2016-10-01

    Full Text Available Dealing with coloured point cloud acquired from terrestrial laser scanner, this paper identifies remaining challenges for a new data structure: the smart point cloud. This concept arises with the statement that massive and discretized spatial information from active remote sensing technology is often underused due to data mining limitations. The generalisation of point cloud data associated with the heterogeneity and temporality of such datasets is the main issue regarding structure, segmentation, classification, and interaction for an immediate understanding. We propose to use both point cloud properties and human knowledge through machine learning to rapidly extract pertinent information, using user-centered information (smart data rather than raw data. A review of feature detection, machine learning frameworks and database systems indexed both for mining queries and data visualisation is studied. Based on existing approaches, we propose a new 3-block flexible framework around device expertise, analytic expertise and domain base reflexion. This contribution serves as the first step for the realisation of a comprehensive smart point cloud data structure.

  15. The Human Remains from HMS Pandora

    Directory of Open Access Journals (Sweden)

    D.P. Steptoe

    2002-04-01

    Full Text Available In 1977 the wreck of HMS Pandora (the ship that was sent to re-capture the Bounty mutineers was discovered off the north coast of Queensland. Since 1983, the Queensland Museum Maritime Archaeology section has carried out systematic excavation of the wreck. During the years 1986 and 1995-1998, more than 200 human bone and bone fragments were recovered. Osteological investigation revealed that this material represented three males. Their ages were estimated at approximately 17 +/-2 years, 22 +/-3 years and 28 +/-4 years, with statures of 168 +/-4cm, 167 +/-4cm, and 166cm +/-3cm respectively. All three individuals were probably Caucasian, although precise determination of ethnicity was not possible. In addition to poor dental hygiene, signs of chronic diseases suggestive of rickets and syphilis were observed. Evidence of spina bifida was seen on one of the skeletons, as were other skeletal anomalies. Various taphonomic processes affecting the remains were also observed and described. Compact bone was observed under the scanning electron microscope and found to be structurally coherent. Profiles of the three skeletons were compared with historical information about the 35 men lost with the ship, but no precise identification could be made. The investigation did not reveal the cause of death. Further research, such as DNA analysis, is being carried out at the time of publication.

  16. An application of uncertain numbers in radio frequency power measurement

    Science.gov (United States)

    Hall, B. D.

    2009-06-01

    The uncertain-numbers method (Hall B D 2006 Metrologia 43 L56-61) is an alternative computational procedure to the Law of Propagation of Uncertainty (LPU) described in the Guide to the Expression of Uncertainty in Measurement. One advantage of the method is that data processing can be carried out in an arbitrary series of steps and much of the mathematical analysis normally associated with the LPU can be automated by software. This has applications for measuring systems, which are modular in design and use internal data processing to apply corrections to raw data. Several scenarios involving radio frequency power measurements are used to illustrate the new method in this context. The scenarios show something of the difficulty inherent in calculating uncertainty for modern measurement systems and in particular highlight the occurrence of systematic errors arising from internal instrument correction factors. Such errors introduce correlation to a series of measurements and must be handled with care when functions of results, such as means, differences and ratios, are required.

  17. English and the Brain Drain: an Uncertain Relationship

    Directory of Open Access Journals (Sweden)

    Houtkamp Christopher

    2016-10-01

    Full Text Available In his book Linguistic Justice for Europe and the World, Van Parijs analyses in one of his chapters the brain drain from non-Anglophone to Anglophone countries, which hurts the economic development of the non-Anglophone states. Van Parijs deems it clear that English is a very important factor to explain high-skilled migration. He, therefore, urges the non-Anglophone countries to relax their linguistic territorial constraints and allow English as a communication language in many different sectors, most notably higher education and scientific research. This would remove the incentive for potential expatriate brains to migrate for linguistic reasons. This article takes a closer look at Van Parijs’ reasoning and proposed solutions. It is concluded that the assumed connection between English and high-skilled migration cannot be proven empirically for research on this topic is scarcely available. Furthermore, the solutions presented by Van Parijs will produce uncertain results at best. Van Parijs rightfully puts the brain drain problem on the political and research agenda, but much more additional studies are needed to formulate solid solutions.

  18. The challenges of making decisions using uncertain data

    Science.gov (United States)

    Segall, Matthew D.; Champness, Edmund J.

    2015-09-01

    All of the experimental compound data with which we work have significant uncertainties, due to imperfect correlations between experimental systems and the ultimate in vivo properties of compounds and the inherent variability in experimental conditions. When using these data to make decisions, it is essential that these uncertainties are taken into account to avoid making inappropriate decisions in the selection of compounds, which can lead to wasted effort and missed opportunities. In this paper we will consider approaches to rigorously account for uncertainties when selecting between compounds or assessing compounds against a property criterion; first for an individual measurement of a single property and then for multiple measurements of a property for the same compound. We will then explore how uncertainties in multiple properties can be combined when assessing compounds against a profile of criteria, a process known as multi-parameter optimisation. This guides rigorous decision-making using complex, uncertain data to focus on compounds with the best chance of success, while avoiding missed opportunities by inappropriately rejecting compounds.

  19. The R Package bgmm : Mixture Modeling with Uncertain Knowledge

    Directory of Open Access Journals (Sweden)

    Przemys law Biecek

    2012-04-01

    Full Text Available Classical supervised learning enjoys the luxury of accessing the true known labels for the observations in a modeled dataset. Real life, however, poses an abundance of problems, where the labels are only partially defined, i.e., are uncertain and given only for a subsetof observations. Such partial labels can occur regardless of the knowledge source. For example, an experimental assessment of labels may have limited capacity and is prone to measurement errors. Also expert knowledge is often restricted to a specialized area and is thus unlikely to provide trustworthy labels for all observations in the dataset. Partially supervised mixture modeling is able to process such sparse and imprecise input. Here, we present an R package calledbgmm, which implements two partially supervised mixture modeling methods: soft-label and belief-based modeling. For completeness, we equipped the package also with the functionality of unsupervised, semi- and fully supervised mixture modeling. On real data we present the usage of bgmm for basic model-fitting in all modeling variants. The package can be applied also to selection of the best-fitting from a set of models with different component numbers or constraints on their structures. This functionality is presented on an artificial dataset, which can be simulated in bgmm from a distribution defined by a given model.

  20. Bayesian multiple-source localization in an uncertain ocean environment.

    Science.gov (United States)

    Dosso, Stan E; Wilmut, Michael J

    2011-06-01

    This paper considers simultaneous localization of multiple acoustic sources when properties of the ocean environment (water column and seabed) are poorly known. A Bayesian formulation is developed in which the environmental parameters, noise statistics, and locations and complex strengths (amplitudes and phases) of multiple sources are considered to be unknown random variables constrained by acoustic data and prior information. Two approaches are considered for estimating source parameters. Focalization maximizes the posterior probability density (PPD) over all parameters using adaptive hybrid optimization. Marginalization integrates the PPD using efficient Markov-chain Monte Carlo methods to produce joint marginal probability distributions for source ranges and depths, from which source locations are obtained. This approach also provides quantitative uncertainty analysis for all parameters, which can aid in understanding of the inverse problem and may be of practical interest (e.g., source-strength probability distributions). In both approaches, closed-form maximum-likelihood expressions for source strengths and noise variance at each frequency allow these parameters to be sampled implicitly, substantially reducing the dimensionality and difficulty of the inversion. Examples are presented of both approaches applied to single- and multi-frequency localization of multiple sources in an uncertain shallow-water environment, and a Monte Carlo performance evaluation study is carried out. © 2011 Acoustical Society of America

  1. The Uncertain Bodies and Spaces of Aging in Place

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    Lauren Penney

    2013-09-01

    Full Text Available In the United States, “aging in place” has been established as the preferred method of aging. This article examines the work, processes, and tensions involved in aging in place in the southwest US, focusing on the experiences of chronically ill older adults receiving Medicare-reimbursed home health care. Based on an in depth ethnography, it  examines the resources and work that go into aging in place amid uncertainty, and highlights how processes related to the integration of person and place are negotiated and contested between older adults, family members, and home health nurses. Drawing on definitions of place from geography, I argue that aging in place should be understood using a processual lens to highlight the ways that health regimes aimed at facilitating aging in place can, at times, reinforce and introduce sense of bodily risk, shift embodiment and daily practice, and require negotiations among household members. I also point to the difficulties people face in maintaining aging in place when supports are lacking and futures uncertain.

  2. Dynamics Model Applied to Pricing Options with Uncertain Volatility

    Directory of Open Access Journals (Sweden)

    Lorella Fatone

    2012-01-01

    model is proposed. The data used to test the calibration problem included observations of asset prices over a finite set of (known equispaced discrete time values. Statistical tests were used to estimate the statistical significance of the two parameters of the Black-Scholes model: the volatility and the drift. The effects of these estimates on the option pricing problem were investigated. In particular, the pricing of an option with uncertain volatility in the Black-Scholes framework was revisited, and a statistical significance was associated with the price intervals determined using the Black-Scholes-Barenblatt equations. Numerical experiments involving synthetic and real data were presented. The real data considered were the daily closing values of the S&P500 index and the associated European call and put option prices in the year 2005. The method proposed here for calibrating the Black-Scholes dynamics model could be extended to other science and engineering models that may be expressed in terms of stochastic dynamical systems.

  3. The expectant management of early pregnancies of uncertain site.

    Science.gov (United States)

    Hahlin, M; Thorburn, J; Bryman, I

    1995-05-01

    The role of expectant management was evaluated in 80 women in whom clinical examination, including vaginal ultrasound, had failed to identify the location of an early pregnancy. In 45 cases, spontaneous resolution of the pregnancy products occurred. A normal intra-uterine pregnancy was diagnosed in 12 patients. A total of 23 patients underwent active therapeutic measures due to an ectopic pregnancy (n = 16) or a spontaneous abortion (n = 7). The effectiveness of different diagnostic measures to identify patients suitable for expectant management was analysed. In 33/34 patients (97%) with a relative daily human chorionic gonadotrophin (HCG) change of -5% and/or serum progesterone > 20 nmol/l, active therapeutic measures were carried out in 22 cases (48%), a normal intra-uterine pregnancy was diagnosed in 12 cases (26%) and spontaneous resolution of the pregnancy products occurred in 12 cases (26%). In conclusion, the combination of a single progesterone assay and serial HCG determinations retrospectively identified early pregnancies of uncertain location in whom expectant management was a safe management option.

  4. Sensor trustworthiness in uncertain time varying stochastic environments

    Science.gov (United States)

    Verma, Ajay; Fernandes, Ronald; Vadakkeveedu, Kalyan

    2011-06-01

    Persistent surveillance applications require unattended sensors deployed in remote regions to track and monitor some physical stimulant of interest that can be modeled as output of time varying stochastic process. However, the accuracy or the trustworthiness of the information received through a remote and unattended sensor and sensor network cannot be readily assumed, since sensors may get disabled, corrupted, or even compromised, resulting in unreliable information. The aim of this paper is to develop information theory based metric to determine sensor trustworthiness from the sensor data in an uncertain and time varying stochastic environment. In this paper we show an information theory based determination of sensor data trustworthiness using an adaptive stochastic reference sensor model that tracks the sensor performance for the time varying physical feature, and provides a baseline model that is used to compare and analyze the observed sensor output. We present an approach in which relative entropy is used for reference model adaptation and determination of divergence of the sensor signal from the estimated reference baseline. We show that that KL-divergence is a useful metric that can be successfully used in determination of sensor failures or sensor malice of various types.

  5. Direct computation of stochastic flow in reservoirs with uncertain parameters

    Energy Technology Data Exchange (ETDEWEB)

    Dainton, M.P.; Nichols, N.K. [Univ. of Reading (United Kingdom); Goldwater, M.H. [VIPS Limited, Kingston-upon-Thames (United Kingdom)

    1997-01-15

    A direct method is presented for determining the uncertainty in reservoir pressure, flow, and net present value (NPV) using the time-dependent, one phase, two- or three-dimensional equations of flow through a porous medium. The uncertainty in the solution is modelled as a probability distribution function and is computed from given statistical data for input parameters such as permeability. The method generates an expansion for the mean of the pressure about a deterministic solution to the system equations using a perturbation to the mean of the input parameters. Hierarchical equations that define approximations to the mean solution at each point and to the field convariance of the pressure are developed and solved numerically. The procedure is then used to find the statistics of the flow and the risked value of the field, defined by the NPV, for a given development scenario. This method involves only one (albeit complicated) solution of the equations and contrasts with the more usual Monte-Carlo approach where many such solutions are required. The procedure is applied easily to other physical systems modelled by linear or nonlinear partial differential equations with uncertain data. 14 refs., 14 figs., 3 tabs.

  6. Direct Computation of Stochastic Flow in Reservoirs with Uncertain Parameters

    Science.gov (United States)

    Dainton, M. P.; Goldwater, M. H.; Nichols, N. K.

    1997-01-01

    A direct method is presented for determining the uncertainty in reservoir pressure, flow, and net present value (NPV) using the time-dependent, one phase, two- or three-dimensional equations of flow through a porous medium. The uncertainty in the solution is modelled as a probability distribution function and is computed from given statistical data for input parameters such as permeability. The method generates an expansion for the mean of the pressure about a deterministic solution to the system equations using a perturbation to the mean of the input parameters. Hierarchical equations that define approximations to the mean solution at each point and to the field covariance of the pressure are developed and solved numerically. The procedure is then used to find the statistics of the flow and the risked value of the field, defined by the NPV, for a given development scenario. This method involves only one (albeit complicated) solution of the equations and contrasts with the more usual Monte-Carlo approach where many such solutions are required. The procedure is applied easily to other physical systems modelled by linear or nonlinear partial differential equations with uncertain data.

  7. Artificial bias typically neglected in comparisons of uncertain atmospheric data

    Science.gov (United States)

    Arola, A. T.; Pitkänen, M. R. A.; Mikkonen, S.; Lipponen, A.; Lehtinen, K. E.

    2016-12-01

    Researchers in atmospheric sciences typically neglect biases caused by regression dilution and regression to the mean (RTM) in comparisons of uncertain data. Regression dilution occurs when the ordinary least squares regression method is used on a predictor with random data uncertainty, which causes the slope to become biased towards zero. RTM on the other hand happens when an extreme observation is accompanied by a less extreme follow-up observation. These biases both originate from random uncertainties of the reference data, which is typically not taken into account and discussed in atmospheric sciences. This is crucial, since essentially all typical atmospheric data have some level of uncertainty. We use synthetic observations of aerosol optical thickness and UV index mimicking real atmospheric data to demonstrate how the biases arise from random data uncertainties of measurements, model output, or satellite retrieval products. Further, we provide examples of typical methods of data comparisons that have a tendency to pronounce the biases. The results show, that data uncertainties can significantly bias data comparisons due regression dilution and RTM, a fact that is known in statistics, but disregarded in atmospheric sciences. Thus we argue, that often these biases are widely regarded as measurement or modeling errors, for instance, while they in fact are artificial. It is essential that atmospheric and geoscience communities become aware of and consider features in research.

  8. acetyltransferases: Influence on Lung Cancer Susceptibility

    African Journals Online (AJOL)

    Lung cancer remains a major health challenge in the world. It is the commonest cause of cancer mortality in men, it has been suggested that genetic susceptibility may contribute to the major risk factor, with increasing prevalence of smoking. Lung cancer has reached epidemic proportions in India. Recently indoor air ...

  9. Non-specific effects of vaccines: plausible and potentially important, but implications uncertain.

    Science.gov (United States)

    Pollard, Andrew J; Finn, Adam; Curtis, Nigel

    2017-11-01

    Non-specific effects (NSE) or heterologous effects of vaccines are proposed to explain observations in some studies that certain vaccines have an impact beyond the direct protection against infection with the specific pathogen for which the vaccines were designed. The importance and implications of such effects remain controversial. There are several known immunological mechanisms which could lead to NSE, since it is widely recognised that the generation of specific immunity is initiated by non-specific innate immune mechanisms that may also have wider effects on adaptive immune function. However, there are no published studies that demonstrate a mechanistic link between such immunological phenomena and clinically relevant NSE in humans. While it is highly plausible that some vaccines do have NSE, their magnitude and duration, and thus importance, remain uncertain. Although the WHO recently concluded that current evidence does not justify changes to immunisation policy, further studies of sufficient size and quality are needed to assess the importance of NSE for all-cause mortality. This could provide insights into vaccine immunobiology with important implications for infant health and survival. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. Ghost Remains After Black Hole Eruption

    Science.gov (United States)

    2009-05-01

    NASA's Chandra X-ray Observatory has found a cosmic "ghost" lurking around a distant supermassive black hole. This is the first detection of such a high-energy apparition, and scientists think it is evidence of a huge eruption produced by the black hole. This discovery presents astronomers with a valuable opportunity to observe phenomena that occurred when the Universe was very young. The X-ray ghost, so-called because a diffuse X-ray source has remained after other radiation from the outburst has died away, is in the Chandra Deep Field-North, one of the deepest X-ray images ever taken. The source, a.k.a. HDF 130, is over 10 billion light years away and existed at a time 3 billion years after the Big Bang, when galaxies and black holes were forming at a high rate. "We'd seen this fuzzy object a few years ago, but didn't realize until now that we were seeing a ghost", said Andy Fabian of the Cambridge University in the United Kingdom. "It's not out there to haunt us, rather it's telling us something - in this case what was happening in this galaxy billions of year ago." Fabian and colleagues think the X-ray glow from HDF 130 is evidence for a powerful outburst from its central black hole in the form of jets of energetic particles traveling at almost the speed of light. When the eruption was ongoing, it produced prodigious amounts of radio and X-radiation, but after several million years, the radio signal faded from view as the electrons radiated away their energy. HDF 130 Chandra X-ray Image of HDF 130 However, less energetic electrons can still produce X-rays by interacting with the pervasive sea of photons remaining from the Big Bang - the cosmic background radiation. Collisions between these electrons and the background photons can impart enough energy to the photons to boost them into the X-ray energy band. This process produces an extended X-ray source that lasts for another 30 million years or so. "This ghost tells us about the black hole's eruption long after

  11. Ciguatera: recent advances but the risk remains.

    Science.gov (United States)

    Lehane, L; Lewis, R J

    2000-11-01

    Ciguatera is an important form of human poisoning caused by the consumption of seafood. The disease is characterised by gastrointestinal, neurological and cardiovascular disturbances. In cases of severe toxicity, paralysis, coma and death may occur. There is no immunity, and the toxins are cumulative. Symptoms may persist for months or years, or recur periodically. The epidemiology of ciguatera is complex and of central importance to the management and future use of marine resources. Ciguatera is an important medical entity in tropical and subtropical Pacific and Indian Ocean regions, and in the tropical Caribbean. As reef fish are increasingly exported to other areas, it has become a world health problem. The disease is under-reported and often misdiagnosed. Lipid-soluble, polyether toxins known as ciguatoxins accumulated in the muscles of certain subtropical and tropical marine finfish cause ciguatera. Ciguatoxins arise from biotransformation in the fish of less polar ciguatoxins (gambiertoxins) produced by Gambierdiscus toxicus, a marine dinoflagellate that lives on macroalgae, usually attached to dead coral. The toxins and their metabolites are concentrated in the food chain when carnivorous fish prey on smaller herbivorous fish. Humans are exposed at the end of the food chain. More than 400 species of fish can be vectors of ciguatoxins, but generally only a relatively small number of species are regularly incriminated in ciguatera. Ciguateric fish look, taste and smell normal, and detection of toxins in fish remains a problem. More than 20 precursor gambiertoxins and ciguatoxins have been identified in G. toxicus and in herbivorous and carnivorous fish. The toxins become more polar as they undergo oxidative metabolism and pass up the food chain. The main Pacific ciguatoxin (P-CTX-1) causes ciguatera at levels=0.1 microg/kg in the flesh of carnivorous fish. The main Caribbean ciguatoxin (C-CTX-1) is less polar and 10-fold less toxic than P-CTX-1. Ciguatoxins

  12. Counselling framework for moderate-penetrance cancer-susceptibility mutations.

    Science.gov (United States)

    Tung, Nadine; Domchek, Susan M; Stadler, Zsofia; Nathanson, Katherine L; Couch, Fergus; Garber, Judy E; Offit, Kenneth; Robson, Mark E

    2016-09-01

    The use of multigene panels for the assessment of cancer susceptibility is expanding rapidly in clinical practice, particularly in the USA, despite concerns regarding the uncertain clinical validity for some gene variants and the uncertain clinical utility of most multigene panels. So-called 'moderate-penetrance' gene mutations associated with cancer susceptibility are identified in approximately 2-5% of individuals referred for clinical testing; some of these mutations are potentially actionable. Nevertheless, the appropriate management of individuals harbouring such moderate-penetrance genetic variants is unclear. The cancer risks associated with mutations in moderate-penetrance genes are lower and different than those reported for high-penetrance gene mutations (such as mutations in BRCA1 and BRCA2, and those associated with Lynch syndrome). The extrapolation of guidelines for the management of individuals with high-penetrance variants of cancer-susceptibility genes to the clinical care of patients with moderate-penetrance gene mutations could result in substantial harm. Thus, we provide a framework for clinical decision-making pending the development of a sufficient evidence base to document the clinical utility of the interventions for individuals with inherited moderate-penetrance gene mutations associated with an increased risk of cancer.

  13. Breast lesions of uncertain malignant nature and limited metastatic potential: Proposals to improve their recognition and clinical management

    Science.gov (United States)

    Rakha, Emad A.; Badve, Sunil; Eusebi, Vincenzo; Reis-Filho, Jorge S.; Fox, Stephen B.; Dabbs, David J.; Decker, Thomas; Hodi, Zsolt; Ichihara, Shu; Lee, Andrew HS.; Palacios, José; Richardson, Andrea L.; Vincent-Salomon, Anne; Schmitt, Fernando C.; Tan, Puay-Hoon; Tse, Gary M.; Ellis, Ian O.

    2016-01-01

    Breast lesions comprise a family of heterogeneous entities with variable patterns of presentation, morphology and clinical behaviour. The majority of breast lesions are traditionally classified into benign and malignant conditions and their behaviour can, in the vast majority of cases, be predicted with a reasonable degree of accuracy. However, there remain lesions which show borderline features and lie in a grey-zone between benign and malignant as their behaviour cannot be predicted reliably. Defined pathological categorisation of such lesions is challenging and for some entities is recognised to be subjective and include a range of diagnoses, and forms of terminology, which may trigger over-treatment or under-treatment. The rarity of these lesions makes acquisition of clinical evidence problematic and limits the development of a sufficient evidence base to support informed decision making by clinicians and patients. Emerging molecular evidence is providing a greater understanding of the biology of these lesions, but this may or may not be reflected in their clinical behaviour. Herein we discuss some breast lesions that are associated with uncertainty regarding classification, behaviour and hence management. These include biologically invasive malignant lesions associated with uncertain metastatic potential such as low-grade adenosquamous carcinoma, low-grade fibromatosis-like spindle cell carcinoma and encapsulated papillary carcinoma. Other lesions remain of uncertain malignant nature such as mammary cylindroma, atypical microglandular adenosis, mammary pleomorphic adenoma and infiltrating epitheliosis. The concept of categories of 1) breast lesions of uncertain malignant nature and 2) breast lesions of limited metastatic potential, are proposed with details of which histological entities could be included in each category, and their management implications are discussed. PMID:26348644

  14. The remaining challenges of pneumococcal disease in adults

    Directory of Open Access Journals (Sweden)

    E. Ludwig

    2012-03-01

    Full Text Available Pneumococcal disease can be divided into invasive disease, i.e. when bacteria are detected in normally sterile body fluids, and noninvasive disease. Pneumococcal disease occurs more frequently in younger children and older adults. It is estimated that, in 2050, 30.3% of the European population will be ≥65 yrs old, compared with 15.7% in 2000. Preventive medicine, including vaccination, is essential for the promotion of healthy ageing. Uptake rates for influenza vaccination in the elderly are generally low, despite recommendations in many countries. In addition, it has been reported that influenza infections can make people more susceptible to pneumococcal infections. Despite pneumococcal vaccination, case fatality rates for patients hospitalised with invasive pneumococcal disease have remained at around 12% since the 1950s. Even when effective antibiotic therapy is administered, mortality can be high amongst immunocompetent patients in intensive care. Timely and accurate diagnosis of pneumococcal disease and identification of patients at high risk of poor outcome is essential to ensure that adequate treatment, including hospitalisation when necessary, is implemented as early as possible. Improved diagnostic techniques and more efficacious treatments may help to reduce the burden of pneumococcal disease, but preventive measures, such as influenza and pneumococcal vaccination, should be promoted in order to avoid preventable disease, particularly in the elderly.

  15. An uncertain journey around the tails of multivariate hydrological distributions

    Science.gov (United States)

    Serinaldi, Francesco

    2013-10-01

    Moving from univariate to multivariate frequency analysis, this study extends the Klemeš' critique of the widespread belief that the increasingly refined mathematical structures of probability functions increase the accuracy and credibility of the extrapolated upper tails of the fitted distribution models. In particular, we discuss key aspects of multivariate frequency analysis applied to hydrological data such as the selection of multivariate design events (i.e., appropriate subsets or scenarios of multiplets that exhibit the same joint probability to be used in design applications) and the assessment of the corresponding uncertainty. Since these problems are often overlooked or treated separately, and sometimes confused, we attempt to clarify properties, advantages, shortcomings, and reliability of results of frequency analysis. We suggest a selection method of multivariate design events with prescribed joint probability based on simple Monte Carlo simulations that accounts for the uncertainty affecting the inference results and the multivariate extreme quantiles. It is also shown that the exploration of the p-level probability regions of a joint distribution returns a set of events that is a subset of the p-level scenarios resulting from an appropriate assessment of the sampling uncertainty, thus tending to overlook more extreme and potentially dangerous events with the same (uncertain) joint probability. Moreover, a quantitative assessment of the uncertainty of multivariate quantiles is provided by introducing the concept of joint confidence intervals. From an operational point of view, the simulated event sets describing the distribution of the multivariate p-level quantiles can be used to perform multivariate risk analysis under sampling uncertainty. As an example of the practical implications of this study, we analyze two case studies already presented in the literature.

  16. A novel medical information management and decision model for uncertain demand optimization.

    Science.gov (United States)

    Bi, Ya

    2015-01-01

    Accurately planning the procurement volume is an effective measure for controlling the medicine inventory cost. Due to uncertain demand it is difficult to make accurate decision on procurement volume. As to the biomedicine sensitive to time and season demand, the uncertain demand fitted by the fuzzy mathematics method is obviously better than general random distribution functions. To establish a novel medical information management and decision model for uncertain demand optimization. A novel optimal management and decision model under uncertain demand has been presented based on fuzzy mathematics and a new comprehensive improved particle swarm algorithm. The optimal management and decision model can effectively reduce the medicine inventory cost. The proposed improved particle swarm optimization is a simple and effective algorithm to improve the Fuzzy interference and hence effectively reduce the calculation complexity of the optimal management and decision model. Therefore the new model can be used for accurate decision on procurement volume under uncertain demand.

  17. BSAC standardized disc susceptibility testing method (version 11).

    Science.gov (United States)

    Howe, R A; Andrews, J M

    2012-12-01

    This article highlights key amendments incorporated into version 11 of the BSAC standardized disc susceptibility testing method, available as Supplementary data at JAC Online (http://jac.oxfordjournals.org/) and on the BSAC web site (http://bsac.org.uk/susceptibility/guidelines-standardized-disc-susceptibility-testing-method/). The basic disc susceptibility testing method remains unchanged, but there have been a number of alterations to the interpretive criteria for certain organism/drug combinations due to continuing harmonization with the EUCAST MIC breakpoints and constant efforts to improve the reliability and clinical applicability of the guidance.

  18. Reproducing an extreme flood with uncertain post-event information

    Directory of Open Access Journals (Sweden)

    D. Fuentes-Andino

    2017-07-01

    Full Text Available Studies for the prevention and mitigation of floods require information on discharge and extent of inundation, commonly unavailable or uncertain, especially during extreme events. This study was initiated by the devastating flood in Tegucigalpa, the capital of Honduras, when Hurricane Mitch struck the city. In this study we hypothesized that it is possible to estimate, in a trustworthy way considering large data uncertainties, this extreme 1998 flood discharge and the extent of the inundations that followed from a combination of models and post-event measured data. Post-event data collected in 2000 and 2001 were used to estimate discharge peaks, times of peak, and high-water marks. These data were used in combination with rain data from two gauges to drive and constrain a combination of well-known modelling tools: TOPMODEL, Muskingum–Cunge–Todini routing, and the LISFLOOD-FP hydraulic model. Simulations were performed within the generalized likelihood uncertainty estimation (GLUE uncertainty-analysis framework. The model combination predicted peak discharge, times of peaks, and more than 90 % of the observed high-water marks within the uncertainty bounds of the evaluation data. This allowed an inundation likelihood map to be produced. Observed high-water marks could not be reproduced at a few locations on the floodplain. Identifications of these locations are useful to improve model set-up, model structure, or post-event data-estimation methods. Rainfall data were of central importance in simulating the times of peak and results would be improved by a better spatial assessment of rainfall, e.g. from radar data or a denser rain-gauge network. Our study demonstrated that it was possible, considering the uncertainty in the post-event data, to reasonably reproduce the extreme Mitch flood in Tegucigalpa in spite of no hydrometric gauging during the event. The method proposed here can be part of a Bayesian framework in which more events

  19. Assessing landslide susceptibility by applying fuzzy sets, possibility evidence-based theories

    Directory of Open Access Journals (Sweden)

    Ibsen Chivatá Cárdenas

    2010-04-01

    Full Text Available A landslide susceptibility model was developed for the city of Manizales, Colombia; landslides have been the city’s main environmental problem. Fuzzy sets and possibility and evidence-based theories were used to construct the mo-del due to the set of circumstances and uncertainty involved in the modelling; uncertainty particularly concerned the lack of representative data and the need for systematically coordinating subjective information. Susceptibility and the uncertainty were estimated via data processing; the model contained data concerning mass vulnerability and uncer-tainty. Output data was expressed on a map defined by linguistic categories or uncertain labels as having low, me-dium, high and very high susceptibility; this was considered appropriate for representing susceptibility. A fuzzy spec-trum was developed for classifying susceptibility levels according to perception and expert opinion. The model sho-wed levels of susceptibility in the study area, ranging from low to high susceptibility (medium susceptibility being mo-re frequent. This article shows the details concerning systematic data processing by presenting theories and tools regarding uncertainty. The concept of fuzzy parameters is introduced; this is useful in modelling phenomena regar-ding uncertainty, complexity and nonlinear performance, showing that susceptibility modelling can be feasible. The paper also shows the great convenience of incorporating uncertainty into modelling and decision-making. However, quantifying susceptibility is not suitable when modelling identified uncertainty because incorporating model output information cannot be reduced into exact or real numerical quantities when the nature of the variables is particularly uncertain. The latter concept is applicable to risk assessment.

  20. Boundary Control of Linear Uncertain 1-D Parabolic PDE Using Approximate Dynamic Programming.

    Science.gov (United States)

    Talaei, Behzad; Jagannathan, Sarangapani; Singler, John

    2017-03-02

    This paper develops a near optimal boundary control method for distributed parameter systems governed by uncertain linear 1-D parabolic partial differential equations (PDE) by using approximate dynamic programming. A quadratic surface integral is proposed to express the optimal cost functional for the infinite-dimensional state space. Accordingly, the Hamilton-Jacobi-Bellman (HJB) equation is formulated in the infinite-dimensional domain without using any model reduction. Subsequently, a neural network identifier is developed to estimate the unknown spatially varying coefficient in PDE dynamics. Novel tuning law is proposed to guarantee the boundedness of identifier approximation error in the PDE domain. A radial basis network (RBN) is subsequently proposed to generate an approximate solution for the optimal surface kernel function online. The tuning law for near optimal RBN weights is created, such that the HJB equation error is minimized while the dynamics are identified and closed-loop system remains stable. Ultimate boundedness (UB) of the closed-loop system is verified by using the Lyapunov theory. The performance of the proposed controller is successfully confirmed by simulation on an unstable diffusion-reaction process.

  1. Reserve design for uncertain responses of coral reefs to climate change.

    Science.gov (United States)

    Mumby, Peter J; Elliott, Ian A; Eakin, C Mark; Skirving, William; Paris, Claire B; Edwards, Helen J; Enríquez, Susana; Iglesias-Prieto, Roberto; Cherubin, Laurent M; Stevens, Jamie R

    2011-02-01

    Rising sea temperatures cause mass coral bleaching and threaten reefs worldwide. We show how maps of variations in thermal stress can be used to help manage reefs for climate change. We map proxies of chronic and acute thermal stress and develop evidence-based hypotheses for the future response of corals to each stress regime. We then incorporate spatially realistic predictions of larval connectivity among reefs of the Bahamas and apply novel reserve design algorithms to create reserve networks for a changing climate. We show that scales of larval dispersal are large enough to connect reefs from desirable thermal stress regimes into a reserve network. Critically, we find that reserve designs differ according to the anticipated scope for phenotypic and genetic adaptation in corals, which remains uncertain. Attempts to provide a complete reserve design that hedged against different evolutionary outcomes achieved limited success, which emphasises the importance of considering the scope for adaptation explicitly. Nonetheless, 15% of reserve locations were selected under all evolutionary scenarios, making them a high priority for early designation. Our approach allows new insights into coral holobiont adaptation to be integrated directly into an adaptive approach to management. © 2010 Blackwell Publishing Ltd/CNRS.

  2. Genetic susceptibility of periodontitis

    NARCIS (Netherlands)

    Laine, M.L.; Crielaard, W.; Loos, B.G.

    2012-01-01

    In this systematic review, we explore and summarize the peer-reviewed literature on putative genetic risk factors for susceptibility to aggressive and chronic periodontitis. A comprehensive literature search on the PubMed database was performed using the keywords ‘periodontitis’ or ‘periodontal

  3. Fourie susceptible.pmd

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    a number of cultivars exhibited field resistance to halo blight and bacterial brown spot, all cultivars were more or less susceptible to .... Cerillos. Alubia. I. 91. 57. Kranskop. Red speckled sugar. II. 97. 63. OPS-RS1. Red speckled sugar. II. 96. 63. OPS-RS2. Red speckled sugar. I. 100. 61. OPS-RS3. Red speckled sugar. II. 97.

  4. Uncertain Governance and Resilient Subjects in the Risk Society

    Directory of Open Access Journals (Sweden)

    Pat O'Malley

    2013-04-01

    Full Text Available Over the past decade or so, a series of new or revitalised strategies have been promoted to govern the highly uncertain threats that risk appears no longer able to prevent. Most owe their ascendancy to the lessons of 9/11, and the ‘bureaucratising of imagination’ that US sources have proposed as a response, by centring the possible, or even merely imaginable, rather than the statistically probable. Precaution, preparedness and speculative pre-emption have been particularly prominent, although new hybrid statistical and speculative techniques have broadened risk techniques to cope with labile conditions of high uncertainty. But while diverse, each establishes a negative and defensive framework of ‘freedom from’ that has been associated with creating a ’neurotic subject’. In the past decade, programs of resilience, and particularly resiliency training, have been developed with the aim of creating subjects able to thrive and prosper under conditions of extreme uncertainty. They constitute a form of governance promoting a positive ‘freedom to’. Reflecting many of the assumptions and goals of neo-liberal politics, resiliency has already emerged as a principal technology for military and business, and may be the answer to the neo-liberal dream of a society of extreme entrepreneurs. Durante la última década, se han promovido varias estrategias nuevas o renovadas destinadas a gestionar amenazas que el riesgo ya no parece capaz de prevenir. La mayoría deben su predominancia a las lecciones aprendidas tras el 11-S, y la “burocratización de la imaginación” que las fuentes estadounidenses han propuesto como respuesta, predominando lo posible, o incluso simplemente lo imaginable, por encima de lo estadísticamente probable. Han predominado la precaución, preparación y especulación preventivas, aunque las nuevas técnicas estadísticas y especulativas híbridas han ampliado las técnicas de riesgo para hacer frente a las

  5. A model for the inverse 1-median problem on trees under uncertain costs

    Directory of Open Access Journals (Sweden)

    Kien Trung Nguyen

    2016-01-01

    Full Text Available We consider the problem of justifying vertex weights of a tree under uncertain costs so that a prespecified vertex become optimal and the total cost should be optimal in the uncertainty scenario. We propose a model which delivers the information about the optimal cost which respect to each confidence level \\(\\alpha \\in [0,1]\\. To obtain this goal, we first define an uncertain variable with respect to the minimum cost in each confidence level. If all costs are independently linear distributed, we present the inverse distribution function of this uncertain variable in \\(O(n^{2}\\log n\\ time, where \\(n\\ is the number of vertices in the tree.

  6. Robust output feedback H-infinity control and filtering for uncertain linear systems

    CERN Document Server

    Chang, Xiao-Heng

    2014-01-01

    "Robust Output Feedback H-infinity Control and Filtering for Uncertain Linear Systems" discusses new and meaningful findings on robust output feedback H-infinity control and filtering for uncertain linear systems, presenting a number of useful and less conservative design results based on the linear matrix inequality (LMI) technique. Though primarily intended for graduate students in control and filtering, the book can also serve as a valuable reference work for researchers wishing to explore the area of robust H-infinity control and filtering of uncertain systems. Dr. Xiao-Heng Chang is a Professor at the College of Engineering, Bohai University, China.

  7. Urban Flood Risk Assessment Under Uncertain Conditions and Scarce Information

    Science.gov (United States)

    Rodríguez-Gaviria, E. M.; Botero-Fernandez, V.

    2015-12-01

    Flood risk management in small urban areas in Colombia has a great degree of uncertainty due to the low availability and quality of data, the non-existent personnel qualified in the collection and processing of data, and the insufficient information to evaluate the risk and vulnerability. It is because of this that two methods are developed: one for the generation of flood threat maps for different return periods combining historical, geomorphological, and hydrological hydraulic methods assisted by remote sensors and SIG through the use of data acquired through field campaigns, official hydrological networks, orthophotos, multitemporal topographic maps, and ASTER, STRM, and LiDAR images. And another method in which categorical variables are established, linking local physical, social, economical, environmental and political-institutional factors that are explored through different media such as reports, news, databases, transects, interviews, community workshops, and surveys conducted at homes. Such variables were included within an analysis of multiple correspondence to conduct a descriptive study of the exposure, susceptibility, and capacity conditions and to create a vulnerability index that was spatially plotted spatially on maps. The uncertainty is reduced in the measure in which local knowledge is used as a source of information acquisition, of validation of what already exists, and of calibration of the proposed methods. This research was applied to the urban centers of Caucasia (Antioquia) and Plato (Magdalena), which have been historically affected by slow flooding of the Magdalena and Cauca river, it being especially useful in the selection of best alternatives for risk management, planning for development, and land use management, with the possibility of replicating it to benefit other municipalities that experience the same reality.

  8. An Extended TOPSIS Method for Multiple Attribute Decision Making based on Interval Neutrosophic Uncertain Linguistic Variables

    Directory of Open Access Journals (Sweden)

    Said Broumi

    2015-03-01

    Full Text Available The interval neutrosophic uncertain linguistic variables can easily express the indeterminate and inconsistent information in real world, and TOPSIS is a very effective decision making method more and more extensive applications. In this paper, we will extend the TOPSIS method to deal with the interval neutrosophic uncertain linguistic information, and propose an extended TOPSIS method to solve the multiple attribute decision making problems in which the attribute value takes the form of the interval neutrosophic uncertain linguistic variables and attribute weight is unknown. Firstly, the operational rules and properties for the interval neutrosophic variables are introduced. Then the distance between two interval neutrosophic uncertain linguistic variables is proposed and the attribute weight is calculated by the maximizing deviation method, and the closeness coefficients to the ideal solution for each alternatives. Finally, an illustrative example is given to illustrate the decision making steps and the effectiveness of the proposed method.

  9. A Precautionary-Principled Approach Towards Uncertain Risks: Review and Decision-Theoretic Elaboration

    NARCIS (Netherlands)

    Ch. Vlek (Charles)

    2009-01-01

    textabstractPrecautionary judgment, decision, and action are needed in situations involving serious uncertain risk. Examples are mountain climbing, nanotechnology, global warming, and international terrorism. The history of the Precautionary Principle (PP) shows that its proponents and opponents

  10. Linear matrix inequality criteria for robust synchronization of uncertain fractional-order chaotic systems

    Science.gov (United States)

    Chen, Liping; Chai, Yi; Wu, Ranchao

    2011-12-01

    This paper is devoted to synchronization of uncertain fractional-order chaotic systems with fractional-order α: 0 fractional-order differential system and the observer-based robust control, two sufficient and necessary conditions for synchronizing uncertain fractional-order chaotic systems with parameter perturbations are presented in terms of linear matrix inequality, which is an efficient method and could be easily solved by the toolbox of MATLAB. Finally, fractional-order uncertain chaotic Lü system with fractional-order α = 0.95 and fractional-order uncertain chaotic Lorenz system with fractional-order α = 1.05 are taken as numerical examples to show the validity and feasibility of the proposed method.

  11. Genetic Susceptibility to Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Sanja Kovacic

    2012-01-01

    Full Text Available Atherosclerosis is a complex multifocal arterial disease involving interactions of multiple genetic and environmental factors. Advances in techniques of molecular genetics have revealed that genetic ground significantly influences susceptibility to atherosclerotic vascular diseases. Besides further investigations of monogenetic diseases, candidate genes, genetic polymorphisms, and susceptibility loci associated with atherosclerotic diseases have been identified in recent years, and their number is rapidly increasing. This paper discusses main genetic investigations fields associated with human atherosclerotic vascular diseases. The paper concludes with a discussion of the directions and implications of future genetic research in arteriosclerosis with an emphasis on prospective prediction from an early age of individuals who are predisposed to develop premature atherosclerosis as well as to facilitate the discovery of novel drug targets.

  12. [Antibiotics susceptibility of Streptococcus and Enterococcus: data of Onerba network].

    Science.gov (United States)

    Vachée, A; Varon, E; Jouy, E; Meunier, D

    2009-05-01

    This work was aimed to analyze trends in susceptibility to antibiotics among the main species of beta-hemolytic streptococci involved in community-acquired infections in human (Streptococcus pyogenes and Streptococcus agalactiae), or in animals (Streptococcus suis and Streptococcus uberis) and also among the main enterocci species, Enterococcus faecalis and Enterococcus faecium. Data were recorded since 1996 through the Onerba networks. S. pyogenes, as the other beta-hemolytic streptococci studied remained fully susceptible to beta-lactam antibiotics. However, susceptibility to macrolides is clearly decreasing in S. pyogenes. In 2002, only 62 to 65% of the strains according to the network considered, were susceptible to erythromycin. A similar trend was observed for S. agalactiae with only 75% of erythromycin susceptibility in 2002, and for both species isolated from animals S. suis and S. uberis, with respectively 35 and 76% of strains susceptible to erythromycin. In enterococci, susceptibility to beta-lactams remained stable between 2000 and 2004. Indeed, the susceptibility to aminopenicillins remained high in E. faecalis (about 98%), whereas the proportion of E. faecium isolates susceptible to these antibiotics were lower than 60%. From 1999 to 2004, various studies conducted in French hospitals showed that the vancomycin resistance among enterococci accounted for less than 2%. However, the recent emergence of glycopeptide resistant enterococci clusters in French hospitals is a matter of concern and emphasizes the need for an ongoing surveillance. Such trend in macrolide resistance among S. pyogenes or S. agalactiae should consequently lead to propose other alternatives in case of beta-lactam allergy, and for pharyngitis, to rethink the place of the culture for susceptibility testing.

  13. Closed-loop simulation of decentralized control using RGA for uncertain binary distillation column

    Science.gov (United States)

    Agustriyanto, R.; Zhang, J.

    2017-11-01

    This paper presents the results of closed-loop simulation for the decentralized control of uncertain distillation column. The RGA (Relative Gain Array) RGA analysis was used as the basis for selecting the configuration of the decentralized control system. PI controller obtained was then tuned with optimization methods. The simulation results show that the RGA analysis requires accurate range for uncertain systems. In addition, closed-loop simulation results confirm the RGA analysis.

  14. Chaos synchronization of uncertain Genesio-Tesi chaotic systems with deadzone nonlinearity

    Science.gov (United States)

    Sun, Yeong-Jeu

    2009-08-01

    In this Letter, the concept of practical synchronization is introduced and the chaos synchronization of uncertain Genesio-Tesi chaotic systems with deadzone nonlinearity is investigated. Based on the time-domain approach, a tracking control is proposed to realize chaos synchronization for the uncertain Genesio-Tesi chaotic systems with deadzone nonlinearity. Moreover, the guaranteed exponential convergence rate and convergence radius can be pre-specified. Finally, a numerical example is provided to illustrate the feasibility and effectiveness of the obtained result.

  15. Chaos synchronization of uncertain Genesio-Tesi chaotic systems with deadzone nonlinearity

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Y.-J., E-mail: yjsun@isu.edu.t [Department of Electrical Engineering, I-Shou University, Kaohsiung, Taiwan 840 (China)

    2009-08-31

    In this Letter, the concept of practical synchronization is introduced and the chaos synchronization of uncertain Genesio-Tesi chaotic systems with deadzone nonlinearity is investigated. Based on the time-domain approach, a tracking control is proposed to realize chaos synchronization for the uncertain Genesio-Tesi chaotic systems with deadzone nonlinearity. Moreover, the guaranteed exponential convergence rate and convergence radius can be pre-specified. Finally, a numerical example is provided to illustrate the feasibility and effectiveness of the obtained result.

  16. Robust Switching Rule Design for Boost Converters with Uncertain Parameters and Disturbances

    Directory of Open Access Journals (Sweden)

    Yang Yang

    2013-01-01

    Full Text Available This paper is concerned with the design problem of robust switching rule for Boost converters with uncertain parameters and disturbances. Firstly, the Boost converter is modeled as a switched affine linear system with uncertain parameters and disturbances. Then, using common Lyapunov function approach and linear matrix inequality (LMI technique, a novel switching rule is proposed such that the model reference tracking performance is satisfied. Finally, a simulation result is provided to show the validity of the proposed method.

  17. Robust Gain-Scheduled PID Controller Design For Uncertain LPV Systems

    Science.gov (United States)

    Veselý, Vojtech; Ilka, Adrian

    2015-01-01

    A novel methodology is proposed for robust gain-scheduled PID controller design for uncertain LPV systems. The proposed design procedure is based on the parameter-dependent quadratic stability approach. A new uncertain LPV system model has been introduced in this paper. To access the performance quality the approach of a parameter varying guaranteed cost is used which allowed to reach for different working points desired performance. Numerical examples show the benefit of the proposed method.

  18. Optimizing Bus Frequencies under Uncertain Demand: Case Study of the Transit Network in a Developing City

    OpenAIRE

    Huang, Zhengfeng; Ren, Gang; Liu, Haixu

    2013-01-01

    Various factors can make predicting bus passenger demand uncertain. In this study, a bilevel programming model for optimizing bus frequencies based on uncertain bus passenger demand is formulated. There are two terms constituting the upper-level objective. The first is transit network cost, consisting of the passengers’ expected travel time and operating costs, and the second is transit network robustness performance, indicated by the variance in passenger travel time. The second term reflect...

  19. Structure identification and adaptive synchronization of uncertain general complex dynamical networks

    Energy Technology Data Exchange (ETDEWEB)

    Xu Yuhua, E-mail: yuhuaxu2004@163.co [College of Information Science and Technology, Donghua University, Shanghai 201620 (China) and Department of Maths, Yunyang Teacher' s College, Hubei 442000 (China); Zhou Wuneng, E-mail: wnzhou@163.co [College of Information Science and Technology, Donghua University, Shanghai 201620 (China); Fang Jian' an [College of Information Science and Technology, Donghua University, Shanghai 201620 (China); Lu Hongqian [Shandong Institute of Light Industry, Shandong Jinan 250353 (China)

    2009-12-28

    This Letter proposes an approach to identify the topological structure and unknown parameters for uncertain general complex networks simultaneously. By designing effective adaptive controllers, we achieve synchronization between two complex networks. The unknown network topological structure and system parameters of uncertain general complex dynamical networks are identified simultaneously in the process of synchronization. Several useful criteria for synchronization are given. Finally, an illustrative example is presented to demonstrate the application of the theoretical results.

  20. Strategic design under uncertain evaluations: Structural analysis of design-build auctions

    OpenAIRE

    Takahashi, Hidenori

    2015-01-01

    I investigate firms' competition over price and product design under uncertain design evaluations in the context of Design-Build (DB) auctions. Reviewers' design evaluations contain uncertainty from a bidder's perspective, leading luck to curtail differences in firms' chances of winning. I model bidders' behavior and derive semiparametric identification of the model primitives. Uncertain evaluations worsen the expected price of design quality, and exacerbate an auctioneer's unc...

  1. Marijuana Usage and Hypnotic Susceptibility

    Science.gov (United States)

    Franzini, Louis R.; McDonald, Roy D.

    1973-01-01

    Anonymous self-reported drug usage data and hypnotic susceptibility scores were obtained from 282 college students. Frequent marijuana users (more than 10 times) showed greater susceptibility to hypnosis than nonusers. (Author)

  2. Retroperitoneal smooth muscle tumor of uncertain malignant potential after hysterectomy: a case report

    Directory of Open Access Journals (Sweden)

    Chun Hoo

    2011-05-01

    Full Text Available Abstract Introduction Smooth muscle tumors of uncertain malignant potential represent a histologically heterogeneous group of uterine smooth muscle tumors that cannot be diagnosed as either benign or malignant. Smooth muscle tumors of uncertain malignant potential are usually clinically benign, but should be considered tumors of low malignant potential because they can occasionally recur or metastasize to distant sites. Case presentation We report the case of a 62-year-old Mongol woman diagnosed with a retroperitoneal smooth muscle tumor of uncertain malignant potential and lung metastasis, with a history of prior hysterectomy. The case was initially misdiagnosed as retroperitoneal sarcoma, and our patient received chemotherapy. However, no interval change in the size of the retroperitoneal mass and metastatic lung nodules was seen over a period of at least five years. She underwent partial resection of the retroperitoneal mass for the purposes of debulking and establishing a histopathological diagnosis. The diagnosis of the retroperitoneal mass was then confirmed as a smooth muscle tumor of uncertain malignant potential. Conclusion Smooth muscle tumors of uncertain malignant potential have an unpredictable clinical course, and relapses generally appear to occur after a long disease-free interval of up to several years. Therefore, patients diagnosed with smooth muscle tumors of uncertain malignant potential should receive long-term follow-up.

  3. Using Uncertain Climate and Development Information in Health Adaptation Planning.

    Science.gov (United States)

    Ebi, Kristie L; Hess, Jeremy J; Isaksen, Tania Busch

    2016-03-01

    To aid health adaptation decision-making, there are increasing efforts to provide climate projections at finer temporal and spatial scales. Relying solely on projected climate changes for longer-term decisions makes the implicit assumption that sources of vulnerability other than climate change will remain the same, which is not very probable. Over longer time horizons, this approach likely over estimates the extent to which climate change could alter the magnitude and pattern of health outcomes, introducing systematic bias into health management decisions. To balance this potential bias, decision-makers also need projections of other drivers of health outcomes that are, like climate change, recognized determinants of some disease burdens. Incorporating projections via an iterative process that allows for regular updates based on new knowledge and experience has the potential to improve the utility of fine-scale climate projections in health system adaptation to climate change.

  4. The Right to Remain Silent in Criminal Trial

    Directory of Open Access Journals (Sweden)

    Gianina Anemona Radu

    2013-05-01

    Full Text Available A person's right not to incriminate oneself or to remain silent and not contribute to their own incrimination is a basic requirement of due process, although the right not to testify against oneself is not expressly guaranteed. This legal right is intended to protect the accused/ the defendant against the authorities’ abusive coercion. The scope of the right not to incriminate oneself is related to criminal matter under the Convention, and thus susceptible or applicable to criminal proceedings concerning all types of crimes as a guarantee to a fair trial. The European Court of Justice ruled that despite the fact that art. 6 paragraph 2 of the Convention does not expressly mention the right not to incriminate oneself and the right not to contribute to their own incrimination (nemo tenetur are ipsum accusare these are generally recognized international rules that are in consistence with the notion of “fair trial” stipulated in art. 6. By virtue of the right to silence, the person charged with a crime is free to answer the questions or not, as he/she believes it is in his/her interest. Therefore, the right to silence involves not only the right not to testify against oneself, but also the right of the accused/ defendant not to incriminate oneself. Thus, the accused/defendant cannot be compelled to assist in the production of evidence and cannot be sanctioned for failing to provide certain documents or other evidence. Obligation to testify against personal will, under the constraint of a fine or any other form of coercion constitutes an interference with the negative aspect of the right to freedom of expression which must be necessary in a democratic society. It is essential to clarify certain issues as far as this right is concerned. First of all, the statutory provision in question is specific to adversarial systems, which are found mainly in Anglo-Saxon countries and are totally different from that underlying the current Romanian Criminal

  5. Neural Correlates of Successful and Unsuccessful Strategical Mechanisms Involved in Uncertain Decision-Making.

    Directory of Open Access Journals (Sweden)

    Julie Giustiniani

    Full Text Available The ability to develop successful long-term strategies in uncertain situations relies on complex neural mechanisms. Although lesion studies have shown some of the mechanisms involved, it is still unknown why some healthy subjects are able to make the right decision whereas others are not. The aim of our study was to investigate neurophysiological differences underlying this ability to develop a successful strategy in a group of healthy subjects playing a monetary card game called the Iowa Gambling Task (IGT. In this task, subjects have to win and earn money by choosing between four decks of cards, two were advantageous in the long term and two disadvantageous. Twenty healthy right-handed subjects performed the IGT while their cerebral activity was recorded by electroencephalography. Based on their behavioral performances, two groups of subjects could clearly be distinguished: one who selected the good decks and thus succeeded in developing a Favorable strategy (9 subjects and one who remained Undecided (11 subjects. No neural difference was found between each group before the selection of a deck, but in both groups a greater negativity was found emerging from the right superior frontal gyrus 600 ms before a disadvantageous selection. During the processing of the feedback, an attenuation of the P200 and P300 waveforms was found for the Undecided group, and a P300 originating from the medial frontal gyrus was found in response to a loss only in the Favorable group. Our results suggest that undecided subjects are hyposensitive to the valence of the cards during gambling, which affects the feedback processing.

  6. Neural Correlates of Successful and Unsuccessful Strategical Mechanisms Involved in Uncertain Decision-Making.

    Science.gov (United States)

    Giustiniani, Julie; Gabriel, Damien; Nicolier, Magali; Monnin, Julie; Haffen, Emmanuel

    2015-01-01

    The ability to develop successful long-term strategies in uncertain situations relies on complex neural mechanisms. Although lesion studies have shown some of the mechanisms involved, it is still unknown why some healthy subjects are able to make the right decision whereas others are not. The aim of our study was to investigate neurophysiological differences underlying this ability to develop a successful strategy in a group of healthy subjects playing a monetary card game called the Iowa Gambling Task (IGT). In this task, subjects have to win and earn money by choosing between four decks of cards, two were advantageous in the long term and two disadvantageous. Twenty healthy right-handed subjects performed the IGT while their cerebral activity was recorded by electroencephalography. Based on their behavioral performances, two groups of subjects could clearly be distinguished: one who selected the good decks and thus succeeded in developing a Favorable strategy (9 subjects) and one who remained Undecided (11 subjects). No neural difference was found between each group before the selection of a deck, but in both groups a greater negativity was found emerging from the right superior frontal gyrus 600 ms before a disadvantageous selection. During the processing of the feedback, an attenuation of the P200 and P300 waveforms was found for the Undecided group, and a P300 originating from the medial frontal gyrus was found in response to a loss only in the Favorable group. Our results suggest that undecided subjects are hyposensitive to the valence of the cards during gambling, which affects the feedback processing.

  7. Dynamic replanning in uncertain environments for a sewer inspection robot

    Directory of Open Access Journals (Sweden)

    Oliver Adria

    2008-11-01

    Full Text Available The sewer inspection robot MAKRO is an autonomous multi-segment robot with worm-like shape driven by wheels. It is currently under development in the project MAKRO-PLUS. The robot has to navigate autonomously within sewer systems. Its first tasks will be to take water probes, analyze it onboard, and measure positions of manholes and pipes to detect polluted-loaded sewage and to improve current maps of sewer systems. One of the challenging problems is the controller software, which should enable the robot to navigate in the sewer system and perform the inspection tasks autonomously, not inflicting any self-damage. This paper focuses on the route planning and replanning aspect of the robot. The robot�s software has four different levels, of which the planning system is the highest level, and the remaining three are controller levels each with a different degree of abstraction. The planner coordinates the sequence of actions that are to be successively executed by the robot.

  8. Dynamic Replanning in Uncertain Environments for a Sewer Inspection Robot

    Directory of Open Access Journals (Sweden)

    Oliver Adria

    2004-03-01

    Full Text Available The sewer inspection robot MAKRO is an autonomous multi-segment robot with worm-like shape driven by wheels. It is currently under development in the project MAKRO-PLUS. The robot has to navigate autonomously within sewer systems. Its first tasks will be to take water probes, analyze it onboard, and measure positions of manholes and pipes to detect polluted-loaded sewage and to improve current maps of sewer systems. One of the challenging problems is the controller software, which should enable the robot to navigate in the sewer system and perform the inspection tasks autonomously, not inflicting any self-damage. This paper focuses on the route planning and replanning aspect of the robot. The robot's software has four different levels, of which the planning system is the highest level, and the remaining three are controller levels each with a different degree of abstraction. The planner coordinates the sequence of actions that are to be successively executed by the robot.

  9. Marine biodiversity–ecosystem functions under uncertain environmental futures

    Science.gov (United States)

    Bulling, Mark T.; Hicks, Natalie; Murray, Leigh; Paterson, David M.; Raffaelli, Dave; White, Piran C. L.; Solan, Martin

    2010-01-01

    Anthropogenic activity is currently leading to dramatic transformations of ecosystems and losses of biodiversity. The recognition that these ecosystems provide services that are essential for human well-being has led to a major interest in the forms of the biodiversity–ecosystem functioning relationship. However, there is a lack of studies examining the impact of climate change on these relationships and it remains unclear how multiple climatic drivers may affect levels of ecosystem functioning. Here, we examine the roles of two important climate change variables, temperature and concentration of atmospheric carbon dioxide, on the relationship between invertebrate species richness and nutrient release in a model benthic estuarine system. We found a positive relationship between invertebrate species richness and the levels of release of NH4-N into the water column, but no effect of species richness on the release of PO4-P. Higher temperatures and greater concentrations of atmospheric carbon dioxide had a negative impact on nutrient release. Importantly, we found significant interactions between the climate variables, indicating that reliably predicting the effects of future climate change will not be straightforward as multiple drivers are unlikely to have purely additive effects, resulting in increased levels of uncertainty. PMID:20513718

  10. Marine biodiversity-ecosystem functions under uncertain environmental futures.

    Science.gov (United States)

    Bulling, Mark T; Hicks, Natalie; Murray, Leigh; Paterson, David M; Raffaelli, Dave; White, Piran C L; Solan, Martin

    2010-07-12

    Anthropogenic activity is currently leading to dramatic transformations of ecosystems and losses of biodiversity. The recognition that these ecosystems provide services that are essential for human well-being has led to a major interest in the forms of the biodiversity-ecosystem functioning relationship. However, there is a lack of studies examining the impact of climate change on these relationships and it remains unclear how multiple climatic drivers may affect levels of ecosystem functioning. Here, we examine the roles of two important climate change variables, temperature and concentration of atmospheric carbon dioxide, on the relationship between invertebrate species richness and nutrient release in a model benthic estuarine system. We found a positive relationship between invertebrate species richness and the levels of release of NH(4)-N into the water column, but no effect of species richness on the release of PO(4)-P. Higher temperatures and greater concentrations of atmospheric carbon dioxide had a negative impact on nutrient release. Importantly, we found significant interactions between the climate variables, indicating that reliably predicting the effects of future climate change will not be straightforward as multiple drivers are unlikely to have purely additive effects, resulting in increased levels of uncertainty.

  11. Uncertain Classification of Variable Stars: Handling Observational GAPS and Noise

    Science.gov (United States)

    Castro, Nicolás; Protopapas, Pavlos; Pichara, Karim

    2018-01-01

    Automatic classification methods applied to sky surveys have revolutionized the astronomical target selection process. Most surveys generate a vast amount of time series, or “lightcurves,” that represent the brightness variability of stellar objects in time. Unfortunately, lightcurves’ observations take several years to be completed, producing truncated time series that generally remain without the application of automatic classifiers until they are finished. This happens because state-of-the-art methods rely on a variety of statistical descriptors or features that present an increasing degree of dispersion when the number of observations decreases, which reduces their precision. In this paper, we propose a novel method that increases the performance of automatic classifiers of variable stars by incorporating the deviations that scarcity of observations produces. Our method uses Gaussian process regression to form a probabilistic model of each lightcurve’s observations. Then, based on this model, bootstrapped samples of the time series features are generated. Finally, a bagging approach is used to improve the overall performance of the classification. We perform tests on the MAssive Compact Halo Object (MACHO) and Optical Gravitational Lensing Experiment (OGLE) catalogs, results show that our method effectively classifies some variability classes using a small fraction of the original observations. For example, we found that RR Lyrae stars can be classified with ~80% accuracy just by observing the first 5% of the whole lightcurves’ observations in the MACHO and OGLE catalogs. We believe these results prove that, when studying lightcurves, it is important to consider the features’ error and how the measurement process impacts it.

  12. Savannahs of Asia: antiquity, biogeography, and an uncertain future.

    Science.gov (United States)

    Ratnam, Jayashree; Tomlinson, Kyle W; Rasquinha, Dina N; Sankaran, Mahesh

    2016-09-19

    The savannahs of Asia remain locally unrecognized as distinctive ecosystems, and continue to be viewed as degraded forests or seasonally dry tropical forests. These colonial-era legacies are problematic, because they fail to recognize the unique diversity of Asian savannahs and the critical roles of fire and herbivory in maintaining ecosystem health and diversity. In this review, we show that: the palaeo-historical evidence suggests that the savannahs of Asia have existed for at least 1 million years, long before widespread landscape modification by humans; savannah regions across Asia have levels of C4 grass endemism and diversity that are consistent with area-based expectations for non-Asian savannahs; there are at least three distinct Asian savannah communities, namely deciduous broadleaf savannahs, deciduous fine-leafed and spiny savannahs and evergreen pine savannahs, with distinct functional ecologies consistent with fire- and herbivory-driven community assembly. Via an analysis of savannah climate domains on other continents, we map the potential extent of savannahs across Asia. We find that the climates of African savannahs provide the closest analogues for those of Asian deciduous savannahs, but that Asian pine savannahs occur in climates different to any of the savannahs in the southern continents. Finally, we review major threats to the persistence of savannahs in Asia, including the mismanagement of fire and herbivory, alien woody encroachment, afforestation policies and future climate uncertainty associated with the changing Asian monsoon. Research agendas that target these issues are urgently needed to manage and conserve these ecosystems.This article is part of the themed issue 'Tropical grassy biomes: linking ecology, human use and conservation'. © 2016 The Author(s).

  13. Susceptibility of pathogenic and nonpathogenic Naegleria ssp

    Energy Technology Data Exchange (ETDEWEB)

    Whiteman, L.Y.

    1988-01-01

    The susceptibility of four species of Naegleria amoebae to complement-mediated lysis was determined. The amoebicidal activity of normal human serum (NHS) and normal guinea pig serum (NGPS) for Naegleria amoebae was measured by an in vitro cytotoxicity assay. Release of radioactivity from amoebae labeled with {sup 3}H-uridine and visual observation with a compound microscope were used as indices of lysis. Susceptibility or resistance to complement-mediated lysis in vitro correlated with the in vivo pathogenic potential. Nonpathogenic Naegleria amoebae were lysed at a faster rate and at higher cell concentrations than were pathogenic amoebae. Electrophoretic analysis of NHS incubated with pathogenic or nonpathogenic Naegleria spp. demonstrated that amoebae activate the complement cascade resulting in the production of C3 and C5 complement cleavage products. Treatment with papain or trypsin for 1 h, but not with sialidase, increase the susceptibility of highly pathogenic, mouse-passaged N. fowleri to lysis. Treatment with actinomycin D, cycloheximide or various protease inhibitors for 4 h did not increase susceptibility to lysis. Neither a repair process involving de novo protein synthesis nor a complement-inactivating protease appear to account for the increase resistance of N. fowleri amoebae to complement-mediated lysis. A binding study with {sup 125}I radiolabeled C9 indicated that the terminal complement component does not remain stably bound to the membrane of pathogenic amoebae.

  14. Maintaining Credibility with the Media and Public in Uncertain Times

    Science.gov (United States)

    Hosansky, D.

    2010-12-01

    The National Center for Atmospheric Research (NCAR) is in a unique position with regard to the complex interface between science, policy makers, the media, and the general public. Because NCAR is sponsored by the National Science Foundation (NSF), it enjoys great credibility. At the same time, it is managed by a non-profit consortium of universities and therefore is free of the constraints that government scientists sometimes face when communicating with reporters and the public. The NCAR Media Office strategically works to protect the credibility of scientists. Its overriding goal is to ensure that the center and the larger scientific community remain a trusted source of information about weather and climate topics, including such controversial topics as climate change. Scientists are freely available to talk with reporters without needing any official clearance. A multi-tier approach is adopted for disseminating science news to the media and public, ranging from news releases for significant, peer-reviewed research results to online, non-technical summaries for research that is more specialized or still in process. The media office directs reporters not only to NCAR scientists, but also to researchers at federal agencies and universities. It works closely with media officers and researchers at other organizations, often helping scientific collaborators connect with reporters. These approaches have helped make NCAR well known in the media industry as an authoritative, credible, and accessible source of information. To further disseminate information about science, the NCAR Media Office is expanding its efforts into multimedia, including video interviews and other footage; animations; and still images. These efforts are often undertaken in collaboration with NSF and other scientific organizations. In addition, the office is putting a greater emphasis on social media, using such tools as Twitter, Facebook, and YouTube to communicate major scientific developments in

  15. Anticipating the uncertain: economic modeling and climate change policy

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Svenn

    2012-11-01

    find that it has a substantial impact, and the size and direction of the effect depend on the specification of the risk and the time preferences. How should temperature stochasticity, deep uncertainty about climate sensitivity and the prospect of learning impact optimal climate policy? Deep uncertainty, or ambiguity, means we lack an agreed upon probability distribution to describe the uncertainty. People are averse to such subjectivity. We find that temperature stochasticity by itself does not alter optimal abatement but increases investment in manmade capital. Secondly, climate sensitivity uncertainty causes higher abatement efforts, while investment rates remain unchanged. Learning by observing temperatures and GHG stocks is too slow to make a relevant contribution to climate policy over the coming decades. Importantly, it is still optimal to increase abatement to insure against the possibility of high damages. Finally, aversion to deep uncertainty has virtually no impact on optimal decisions.(Author)

  16. Magnetic susceptibilities of minerals

    Science.gov (United States)

    Rosenblum, Sam; Brownfield, I.K.

    2000-01-01

    Magnetic separation of minerals is a topic that is seldom reported in the literature for two reasons. First, separation data generally are byproducts of other projects; and second, this study requires a large amount of patience and is unusually tedious. Indeed, we suspect that most minerals probably are never investigated for this property. These data are timesaving for mineralogists who concentrate mono-mineralic fractions for chemical analysis, age dating, and for other purposes. The data can certainly be used in the ore-beneficiation industries. In some instances, magnetic-susceptibility data may help in mineral identification, where other information is insufficient. In past studies of magnetic separation of minerals, (Gaudin and Spedden, 1943; Tille and Kirkpatrick, 1956; Rosenblum, 1958; Rubinstein and others, 1958; Flinter, 1959; Hess, 1959; Baker, 1962; Meric and Peyre, 1963; Rojas and others, 1965; and Duchesne, 1966), the emphasis has been on the ferromagnetic and paramagnetic ranges of extraction. For readers interested in the history of magnetic separation of minerals, Krumbein and Pettijohn (1938, p. 344-346) indicated nine references back to 1848. The primary purpose of this paper is to report the magnetic-susceptibility data on as many minerals as possible, similar to tables of hardness, specific gravity, refractive indices, and other basic physical properties of minerals. A secondary purpose is to demonstrate that the total and best extraction ranges are influenced by the chemistry of the minerals. The following notes are offered to help avoid problems in separating a desired mineral concentrate from mixtures of mineral grains.

  17. Alcohol increases hypnotic susceptibility.

    Science.gov (United States)

    Semmens-Wheeler, Rebecca; Dienes, Zoltán; Duka, Theodora

    2013-09-01

    One approach to hypnosis suggests that for hypnotic experience to occur frontal lobe activity must be attenuated. For example, cold control theory posits that a lack of awareness of intentions is responsible for the experience of involuntariness and/or the subjective reality of hypnotic suggestions. The mid-dorso-lateral prefrontal cortex and the ACC are candidate regions for such awareness. Alcohol impairs frontal lobe executive function. This study examined whether alcohol affects hypnotisability. We administered 0.8 mg/kg of alcohol or a placebo to 32 medium susceptible participants. They were subsequently hypnotised and given hypnotic suggestions. All participants believed they had received some alcohol. Participants in the alcohol condition were more susceptible to hypnotic suggestions than participants in the placebo condition. Impaired frontal lobe activity facilitates hypnotic responding, which supports theories postulating that attenuation of executive function facilitates hypnotic response, and contradicts theories postulating that hypnotic response involves enhanced inhibitory, attentional or other executive function. Copyright © 2013. Published by Elsevier Inc.

  18. Care seeking for maternal health: challenges remain for poor women

    African Journals Online (AJOL)

    Bernt Lindtjorn

    and extend labor. Some women acknowledged that a young mother is physically unprepared for childbirth and therefore more susceptible to complications. The majority of all respondents identified breech presentation, prolonged labor, maternal exhaustion retained placenta, prolapsed uterus and excessive bleeding in the ...

  19. Enabling time-dependent uncertain eco-weights for road networks

    DEFF Research Database (Denmark)

    Hu, Jilin; Yang, Bin; Jensen, Christian S.

    2017-01-01

    transportation. The foundation of eco-routing is a weighted-graph representation of a road network in which road segments, or edges, are associated with eco-weights that capture the GHG emissions caused by traversing the edges. Due to the dynamics of traffic, the eco-weights are best modeled as being time......Reduction of greenhouse gas (GHG) emissions from transportation is an essential part of the efforts to prevent global warming and climate change. Eco-routing, which enables drivers to use the most environmentally friendly routes, is able to substantially reduce GHG emissions from vehicular...... dependent and uncertain. We formalize the problem of assigning a time-dependent, uncertain eco-weight to each edge in a road network based on historical GPS records. In particular, a sequence of histograms is employed to describe the uncertain eco-weight of an edge at different time intervals. Compression...

  20. Performance analysis of active disturbance rejection tracking control for a class of uncertain LTI systems.

    Science.gov (United States)

    Xue, Wenchao; Huang, Yi

    2015-09-01

    The paper considers the tracking problem for a class of uncertain linear time invariant (LTI) systems with both uncertain parameters and external disturbances. The active disturbance rejection tracking controller is designed and the resulting closed-loop system's characteristics are comprehensively studied. In the time-domain, it is proven that the output of closed-loop system can approach its ideal trajectory in the transient process against different kinds of uncertainties by tuning the bandwidth of extended state observer (ESO). In the frequency-domain, different kinds of parameters' influences on the phase margin and the crossover frequency of the resulting control system are illuminated. Finally, the effectiveness and robustness of the controller are verified through the actuator position control system with uncertain parameters and load disturbances in the simulations. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Genetic susceptibility to pancreatic cancer.

    Science.gov (United States)

    Klein, Alison P

    2012-01-01

    Pancreatic cancer is the fourth leading cause of cancer death in both men and women in the United States. However, it has the poorest prognosis of any major tumor type, with a 5-yr survival rate of approximately 5%. Cigarette smoking, increased body mass index, heavy alcohol consumption, and a diagnosis of diabetes mellitus have all been demonstrated to increase risk of pancreatic cancer. A family history of pancreatic cancer has also been associated with increased risk suggesting inherited genetic factors also play an important role, with approximately 5-10% of pancreatic cancer patients reporting family history of pancreatic cancer. While the genetic basis for the majority of the familial clustering of pancreatic cancer remains unclear, several important pancreatic cancer genes have been identified. These consist of high penetrance genes including BRCA2 or PALB2, to more common genetic variation associated with a modest increase risk of pancreatic cancer such as genetic variation at the ABO blood group locus. Recent advances in genotyping and genetic sequencing have accelerated the rate at which novel pancreatic cancer susceptibility genes have been identified with several genes identified within the past few years. This review addresses our current understanding of the familial aggregation of pancreatic cancer, established pancreatic cancer susceptablity genes and how this knowledge informs risk assessment and screening for high-risk families. Copyright © 2011 Wiley Periodicals, Inc.

  2. Genetic Susceptibility to Pancreatic Cancer

    Science.gov (United States)

    Klein, Alison P.

    2013-01-01

    Pancreatic cancer is the fourth leading cause of cancer death in both men and women in the United States. However, it has the poorest prognosis of any major tumor type, with a 5-yr survival rate of approximately 5%. Cigarette smoking, increased body mass index, heavy alcohol consumption, and a diagnosis of diabetes mellitus have all been demonstrated to increase risk of pancreatic cancer. A family history of pancreatic cancer has also been associated with increased risk suggesting inherited genetic factors also play an important role, with approximately 5–10% of pancreatic cancer patients reporting family history of pancreatic cancer. While the genetic basis for the majority of the familial clustering of pancreatic cancer remains unclear, several important pancreatic cancer genes have been identified. These consist of high penetrance genes including BRCA2 or PALB2, to more common genetic variation associated with a modest increase risk of pancreatic cancer such as genetic variation at the ABO blood group locus. Recent advances in genotyping and genetic sequencing have accelerated the rate at which novel pancreatic cancer susceptibility genes have been identified with several genes identified within the past few years. This review addresses our current understanding of the familial aggregation of pancreatic cancer, established pancreatic cancer susceptablity genes and how this knowledge informs risk assessment and screening for high-risk families. PMID:22162228

  3. Graphene susceptibility in Holstein model

    Energy Technology Data Exchange (ETDEWEB)

    Mousavi, Hamze, E-mail: hamze.mousavi@gmail.co [Department of Physics, Razi University, Kermanshah (Iran, Islamic Republic of); Nano Science and Nano Technology Research Center, Razi University, Kermanshah (Iran, Islamic Republic of)

    2011-06-15

    We study the effects of the electron-phonon interaction on the temperature dependence of the orbital magnetic susceptibility of monolayer graphene. We use the linear response theory and Green's function formalism within the Holstein Hamiltonian model. The results show that the effects of the electron-phonon interaction on the susceptibility of graphene sheet have different behaviors in two temperature regions. In the low temperature region, susceptibility increases when the electron-phonon coupling strength increases. On the other hand, the susceptibility reduces with increasing the electron-phonon coupling strength in the high temperature region. - Highlights: Effect of electron-phonon interaction on the susceptibility of graphene is studied. Linear response theory and Green's function technique in Holstein model are used. Effect of electron-phonon on susceptibility has different behaviors in two temperature regions.

  4. Topological susceptibility from slabs

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, Wolfgang [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70-543, Distrito Federal, C.P. 04510 (Mexico); Forcrand, Philippe de [Institute for Theoretical Physics, ETH Zürich,CH-8093 Zürich (Switzerland); CERN, Physics Department, TH Unit, CH-1211 Geneva 23 (Switzerland); Gerber, Urs [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, A.P. 70-543, Distrito Federal, C.P. 04510 (Mexico); Instituto de Física y Matemáticas, Universidad Michoacana de San Nicolás de Hidalgo,Edificio C-3, Apdo. Postal 2-82, Morelia, Michoacán, C.P. 58040 (Mexico)

    2015-12-14

    In quantum field theories with topological sectors, a non-perturbative quantity of interest is the topological susceptibility χ{sub t}. In principle it seems straightforward to measure χ{sub t} by means of Monte Carlo simulations. However, for local update algorithms and fine lattice spacings, this tends to be difficult, since the Monte Carlo history rarely changes the topological sector. Here we test a method to measure χ{sub t} even if data from only one sector are available. It is based on the topological charges in sub-volumes, which we denote as slabs. Assuming a Gaussian distribution of these charges, this method enables the evaluation of χ{sub t}, as we demonstrate with numerical results for non-linear σ-models.

  5. Topological Susceptibility from Slabs

    CERN Document Server

    Bietenholz, Wolfgang; Gerber, Urs

    2015-01-01

    In quantum field theories with topological sectors, a non-perturbative quantity of interest is the topological susceptibility chi_t. In principle it seems straightforward to measure chi_t by means of Monte Carlo simulations. However, for local update algorithms and fine lattice spacings, this tends to be difficult, since the Monte Carlo history rarely changes the topological sector. Here we test a method to measure chi_t even if data from only one sector are available. It is based on the topological charges in sub-volumes, which we denote as slabs. Assuming a Gaussian distribution of these charges, this method enables the evaluation of chi_t, as we demonstrate with numerical results for non-linear sigma-models.

  6. Numerical Solution of Uncertain Beam Equations Using Double Parametric Form of Fuzzy Numbers

    Directory of Open Access Journals (Sweden)

    Smita Tapaswini

    2013-01-01

    Full Text Available Present paper proposes a new technique to solve uncertain beam equation using double parametric form of fuzzy numbers. Uncertainties appearing in the initial conditions are taken in terms of triangular fuzzy number. Using the single parametric form, the fuzzy beam equation is converted first to an interval-based fuzzy differential equation. Next, this differential equation is transformed to crisp form by applying double parametric form of fuzzy number. Finally, the same is solved by homotopy perturbation method (HPM to obtain the uncertain responses subject to unit step and impulse loads. Obtained results are depicted in terms of plots to show the efficiency and powerfulness of the methodology.

  7. Adaptive Synchronization for a Class of Uncertain Fractional-Order Neural Networks

    Directory of Open Access Journals (Sweden)

    Heng Liu

    2015-10-01

    Full Text Available In this paper, synchronization for a class of uncertain fractional-order neural networks subject to external disturbances and disturbed system parameters is studied. Based on the fractional-order extension of the Lyapunov stability criterion, an adaptive synchronization controller is designed, and fractional-order adaptation law is proposed to update the controller parameter online. The proposed controller can guarantee that the synchronization errors between two uncertain fractional-order neural networks converge to zero asymptotically. By using some proposed lemmas, the quadratic Lyapunov functions are employed in the stability analysis. Finally, numerical simulations are presented to confirm the effectiveness of the proposed method.

  8. Observer-Based Robust Controller Design for Nonlinear Fractional-Order Uncertain Systems via LMI

    Directory of Open Access Journals (Sweden)

    Jing Qiu

    2017-01-01

    Full Text Available We discuss the observer-based robust controller design problem for a class of nonlinear fractional-order uncertain systems with admissible time-variant uncertainty in the case of the fractional-order satisfying 0<α<1. Based on direct Lyapunov approach, a sufficient condition for the robust asymptotic stability of the observer-based nonlinear fractional-order uncertain systems is presented. Employing Finsler’s Lemma, the systematic robust stabilization design algorithm is then proposed in terms of linear matrix inequalities (LMIs. The efficiency and advantage of the proposed algorithm are finally illustrated by two numerical simulations.

  9. Finite-time synchronization of uncertain coupled switched neural networks under asynchronous switching.

    Science.gov (United States)

    Wu, Yuanyuan; Cao, Jinde; Li, Qingbo; Alsaedi, Ahmed; Alsaadi, Fuad E

    2017-01-01

    This paper deals with the finite-time synchronization problem for a class of uncertain coupled switched neural networks under asynchronous switching. By constructing appropriate Lyapunov-like functionals and using the average dwell time technique, some sufficient criteria are derived to guarantee the finite-time synchronization of considered uncertain coupled switched neural networks. Meanwhile, the asynchronous switching feedback controller is designed to finite-time synchronize the concerned networks. Finally, two numerical examples are introduced to show the validity of the main results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. An Uncertain Wage Contract Model with Adverse Selection and Moral Hazard

    Directory of Open Access Journals (Sweden)

    Xiulan Wang

    2014-01-01

    it can be characterized as an uncertain variable. Moreover, the employee's effort is unobservable to the employer, and the employee can select her effort level to maximize her utility. Thus, an uncertain wage contract model with adverse selection and moral hazard is established to maximize the employer's expected profit. And the model analysis mainly focuses on the equivalent form of the proposed wage contract model and the optimal solution to this form. The optimal solution indicates that both the employee's effort level and the wage increase with the employee's ability. Lastly, a numerical example is given to illustrate the effectiveness of the proposed model.

  11. Robust Fuzzy Control for Fractional-Order Uncertain Hydroturbine Regulating System with Random Disturbances

    Directory of Open Access Journals (Sweden)

    Fengjiao Wu

    2016-01-01

    Full Text Available The robust fuzzy control for fractional-order hydroturbine regulating system is studied in this paper. First, the more practical fractional-order hydroturbine regulating system with uncertain parameters and random disturbances is presented. Then, on the basis of interval matrix theory and fractional-order stability theorem, a fuzzy control method is proposed for fractional-order hydroturbine regulating system, and the stability condition is expressed as a group of linear matrix inequalities. Furthermore, the proposed method has good robustness which can process external random disturbances and uncertain parameters. Finally, the validity and superiority are proved by the numerical simulations.

  12. Constrained regulator problem for linear uncertain systems: control of a pH process

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available The regulator problem for linear uncertain continuous-time systems having control constraints is considered. Necessary and sufficient conditions of positive invariance of polyhedral domains are extended to the case of continuous-time uncertain systems. Robust constrained regulators are then derived. An application to the control of pH in a stirred tank is then presented. First, the uncertainty in the pH process is evaluated from first-principle models, then the design of a robust constrained regulator is presented. Simulation results show that this control law is easy to implement and that robust asymptotic stability and control admissibility are guaranteed.

  13. 7 CFR 160.29 - Containers to remain intact.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Containers to remain intact. 160.29 Section 160.29... STANDARDS FOR NAVAL STORES Analysis, Inspection, and Grading on Request § 160.29 Containers to remain intact... the containers holding such naval stores remain intact as sampled until the analysis, classification...

  14. Uncertain Fragments

    NARCIS (Netherlands)

    Theodoridou, Danae

    2015-01-01

    The article revisits notes, thoughts and texts related to the notion of the “open work”, as these were gathered from its author during the project Syros – a bet on the potentiality of cooperation (Syros, July ’13). It presents a historical review of the way the term has been discussed and practiced

  15. Impact of US Biofuel Policy in the Presence of Uncertain Climate Conditions

    NARCIS (Netherlands)

    Nuñez, H.M.; Trujillo Barrera, A.A.

    2014-01-01

    We analyze the impact of total and partial waivers of the US Renewable Fuel Standard (RFS) under uncertain changes in climate conditions that affects crop yield distributions. Results show that reducing RFS would make world agricultural consumers better off, and increase the US corn share in the

  16. Enhanced Radar Imaging in Uncertain Environment: A Descriptive Experiment Design Regularization Approach

    Directory of Open Access Journals (Sweden)

    Yuriy Shkvarko

    2008-01-01

    Full Text Available A new robust technique for high-resolution reconstructive imaging is developed as required for enhanced remote sensing (RS with imaging array radar or/and synthetic aperture radar (SAR operating in an uncertain RS environment. The operational scenario uncertainties are associated with the unknown statistics of perturbations of the signal formation operator (SFO in turbulent medium, imperfect array calibration, finite dimensionality of measurements, uncontrolled antenna vibrations, and random carrier trajectory deviations in the case of SAR. We propose new descriptive experiment design regularization (DEDR approach to treat the uncertain radar image enhancement/reconstruction problems. The proposed DEDR incorporates into the minimum risk (MR nonparametric estimation strategy the experiment design-motivated operational constraints algorithmically coupled with the worst-case statistical performance (WCSP optimization-based regularization. The MR objective functional is constrained by the WCSP information, and the robust DEDR image reconstruction operator applicable to the scenarios with the low-rank uncertain estimated data correlation matrices is found. We report and discuss some simulation results related to enhancement of the uncertain SAR imagery indicative of the significantly increased performance efficiency gained with the developed approach.

  17. Frequent Symptom Sets Identification from Uncertain Medical Data in Differentially Private Way

    Directory of Open Access Journals (Sweden)

    Zhe Ding

    2017-01-01

    Full Text Available Data mining techniques are applied to identify hidden patterns in large amounts of patient data. These patterns can assist physicians in making more accurate diagnosis. For different physical conditions of patients, the same physiological index corresponds to a different symptom association probability for each patient. Data mining technologies based on certain data cannot be directly applied to these patients’ data. Patient data are sensitive data. An adversary with sufficient background information can make use of the patterns mined from uncertain medical data to obtain the sensitive information of patients. In this paper, a new algorithm is presented to determine the top K most frequent itemsets from uncertain medical data and to protect data privacy. Based on traditional algorithms for mining frequent itemsets from uncertain data, our algorithm applies sparse vector algorithm and the Laplace mechanism to ensure differential privacy for the top K most frequent itemsets for uncertain medical data and the expected supports of these frequent itemsets. We prove that our algorithm can guarantee differential privacy in theory. Moreover, we carry out experiments with four real-world scenario datasets and two synthetic datasets. The experimental results demonstrate the performance of our algorithm.

  18. The Data Uncertainty Engine (DUE): a software tool for assessing and simulating uncertain environmental variables

    NARCIS (Netherlands)

    Brown, J.D.; Heuvelink, G.B.M.

    2007-01-01

    This paper describes a software tool for: (1) assessing uncertainties in environmental data; and (2) generating realisations of uncertain data for use in uncertainty propagation analyses: the ¿Data Uncertainty Engine (DUE)¿. Data may be imported into DUE from file or from a database, and are

  19. Optimal core acquisition and remanufacturing policies under uncertain core quality fractions

    NARCIS (Netherlands)

    Teunter, Ruud H.; Flapper, Simme Douwe P.

    2011-01-01

    Cores acquired by a remanufacturer are typically highly variable in quality. Even if the expected fractions of the various quality levels are known, then the exact fractions when acquiring cores are still uncertain. Our model incorporates this uncertainty in determining optimal acquisition decisions

  20. Robust Optimization-Based Generation Self-Scheduling under Uncertain Price

    Directory of Open Access Journals (Sweden)

    Xiao Luo

    2011-01-01

    Full Text Available This paper considers generation self-scheduling in electricity markets under uncertain price. Based on the robust optimization (denoted as RO methodology, a new self-scheduling model, which has a complicated max-min optimization structure, is set up. By using optimal dual theory, the proposed model is reformulated to an ordinary quadratic and quadratic cone programming problems in the cases of box and ellipsoidal uncertainty, respectively. IEEE 30-bus system is used to test the new model. Some comparisons with other methods are done, and the sensitivity with respect to the uncertain set is analyzed. Comparing with the existed uncertain self-scheduling approaches, the new method has twofold characteristics. First, it does not need a prediction of distribution of random variables and just requires an estimated value and the uncertain set of power price. Second, the counterpart of RO corresponding to the self-scheduling is a simple quadratic or quadratic cone programming. This indicates that the reformulated problem can be solved by many ordinary optimization algorithms.

  1. On existence of control for a class of uncertain dynamical systems ...

    African Journals Online (AJOL)

    In this paper we prove the existence of control for input bounded uncertain dynamical system, modeled on Euclidean spaces of dimensions n and m. We apply the Conjugate Gradient Method (C.G.M) in generating algorithms to compute control signals for the class of problem under consideration. Keywords: Control ...

  2. Ambition gone awry: the long-term socioeconomic consequences of misaligned and uncertain ambitions in adolescence.

    Science.gov (United States)

    Sabates, Ricardo; Harris, Angel L; Staff, Jeremy

    2011-01-01

    The objective of this study was to investigate whether misaligned or uncertain ambitions in adolescence influence the process of socioeconomic attainment. Using 34 years of longitudinal data from the British Cohort Study (BCS70), we considered whether youth with (1) misaligned ambitions (i.e., those who either over- or underestimate the level of education required for their desired occupation), (2) both low occupational aspirations and educational expectations (low-aligned ambitions), and (3) uncertainty with regard to their future occupations (uncertain ambitions) at age 16 experienced more unemployment spells, lower educational attainment, and lower hourly wages in adulthood compared to youth with high occupational aspirations and educational expectations (high-aligned ambitions). Youth who hold misaligned or uncertain aspirations show long-term deficits in employment stability and educational attainment, which in turn leads to lower wage attainments at age 34. Misaligned and uncertain ambitions in adolescence compromise the construction of life paths and the realization of long-term educational and occupational goals.

  3. Urban School Finance: Increased Standards and Accountability in Uncertain Economic Times.

    Science.gov (United States)

    Rice, Jennifer King; Roellke, Christopher

    2003-01-01

    Discusses issues related to the funding of urban schools during uncertain economic periods. Includes the complexity of urban school reform, teacher supply and quality in urban schools, nontraditional support for urban schools, and markets and accountability in urban schools. (Contains 36 references.) (PKP)

  4. Using reference trajectories to predicted uncertain systems: exemplified on a power plant

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Mataji, B.

    2007-01-01

    This paper presents a method for prediction of uncertain closed loop systems, where the uncertainties are depending on operating points. Such model uncertainties are often present when complicated non-linear systems are predicted. The method uses precomputed mean and variances of the prediction e...

  5. Fuzzy Stochastic Petri Nets for Modeling Biological Systems with Uncertain Kinetic Parameters.

    Science.gov (United States)

    Liu, Fei; Heiner, Monika; Yang, Ming

    2016-01-01

    Stochastic Petri nets (SPNs) have been widely used to model randomness which is an inherent feature of biological systems. However, for many biological systems, some kinetic parameters may be uncertain due to incomplete, vague or missing kinetic data (often called fuzzy uncertainty), or naturally vary, e.g., between different individuals, experimental conditions, etc. (often called variability), which has prevented a wider application of SPNs that require accurate parameters. Considering the strength of fuzzy sets to deal with uncertain information, we apply a specific type of stochastic Petri nets, fuzzy stochastic Petri nets (FSPNs), to model and analyze biological systems with uncertain kinetic parameters. FSPNs combine SPNs and fuzzy sets, thereby taking into account both randomness and fuzziness of biological systems. For a biological system, SPNs model the randomness, while fuzzy sets model kinetic parameters with fuzzy uncertainty or variability by associating each parameter with a fuzzy number instead of a crisp real value. We introduce a simulation-based analysis method for FSPNs to explore the uncertainties of outputs resulting from the uncertainties associated with input parameters, which works equally well for bounded and unbounded models. We illustrate our approach using a yeast polarization model having an infinite state space, which shows the appropriateness of FSPNs in combination with simulation-based analysis for modeling and analyzing biological systems with uncertain information.

  6. Response and reliability analysis of nonlinear uncertain dynamical structures by the probability density evolution method

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.; Peng, Yongbo; Sichani, Mahdi Teimouri

    2016-01-01

    The paper deals with the response and reliability analysis of hysteretic or geometric nonlinear uncertain dynamical systems of arbitrary dimensionality driven by stochastic processes. The approach is based on the probability density evolution method proposed by Li and Chen (Stochastic dynamics...

  7. Adaptive memory in multi-model switching control of uncertain plants

    NARCIS (Netherlands)

    Battistelli, Giorgio; Mosca, Edoardo; Tesi, Pietro

    This paper describes some recent results in multi-model switching control. The scheme here considered embeds a finite family of pre-designed controllers and a high-level unit which selects, at each instant of time, the candidate controller to be placed in feedback to the uncertain plant. The study

  8. Robust decentralized output regulation with single or multiple reference signals for uncertain heterogeneous systems

    NARCIS (Netherlands)

    Liu, Hui; De Persis, Claudio; Cao, Ming

    We consider the problem in which N coupled heterogeneous uncertain linear systems aim at tracking one or more reference signals generated by given exosystems under the restriction that not all the systems are directly connected to the exosystems. To tackle this problem, the reference signals are

  9. Controllable uncertain opinion diffusion under confidence bound and unpredicted diffusion probability

    Science.gov (United States)

    Yan, Fuhan; Li, Zhaofeng; Jiang, Yichuan

    2016-05-01

    The issues of modeling and analyzing diffusion in social networks have been extensively studied in the last few decades. Recently, many studies focus on uncertain diffusion process. The uncertainty of diffusion process means that the diffusion probability is unpredicted because of some complex factors. For instance, the variety of individuals' opinions is an important factor that can cause uncertainty of diffusion probability. In detail, the difference between opinions can influence the diffusion probability, and then the evolution of opinions will cause the uncertainty of diffusion probability. It is known that controlling the diffusion process is important in the context of viral marketing and political propaganda. However, previous methods are hardly feasible to control the uncertain diffusion process of individual opinion. In this paper, we present suitable strategy to control this diffusion process based on the approximate estimation of the uncertain factors. We formulate a model in which the diffusion probability is influenced by the distance between opinions, and briefly discuss the properties of the diffusion model. Then, we present an optimization problem at the background of voting to show how to control this uncertain diffusion process. In detail, it is assumed that each individual can choose one of the two candidates or abstention based on his/her opinion. Then, we present strategy to set suitable initiators and their opinions so that the advantage of one candidate will be maximized at the end of diffusion. The results show that traditional influence maximization algorithms are not applicable to this problem, and our algorithm can achieve expected performance.

  10. Path Planning for First Responders in the Presence of Moving Obstacles With Uncertain Boundaries

    NARCIS (Netherlands)

    Wang, Z.; Zlatanova, S.; van Oosterom, P.J.M.

    2017-01-01

    In this paper, we study path planning for first responders in the presence of uncertain moving obstacles. To support the path planning, in our research we use hazard simulation to provide the predicted information of moving obstacles. A major problem in using hazard simulation is that the

  11. Microwave susceptibility experiments

    Energy Technology Data Exchange (ETDEWEB)

    McConaghy, C.

    1984-05-29

    In certain experimental environments, systems can be affected or damaged by microwave pulses. I have conducted tests at LLNL to understand the phenomenology of microwave susceptibility of system components and subsystem components. To date, my experiments have concentrated on bipolar transistors, similar to what might be used in discrete analog circuits, and on CMOS RAM chips, which might be used in a computer memory system. I observed a decrease in failure energies for both the transistor and the integrated curcuit as I shortened the microwave pulse width. An S band (2.86 GHz) transmit/receive (T/R) tube has also been tested both at S band and at X band (8.16 GHz). The S band pulse had limitations in rise-time from zero power, which had an effect on the amount of power that could be transmitted through the T/R tube, as much as 0.7% of the incident power passed through the tube. All tests were conducted in closed-waveguide or coax test-fixtures, in contrast to the anechoic chambers utilized by other experimenters. I have used both S band and X band Klystron generators. For very high power (greater than 1 MW), I used an additional pulse-compression cavity at S band. Other subsystem components such as an X band mixer and an X band T/R tube will be tested in the future. 8 references.

  12. [Antimicrobial susceptibility cumulative reports].

    Science.gov (United States)

    Canut-Blasco, Andrés; Calvo, Jorge; Rodríguez-Díaz, Juan Carlos; Martínez-Martínez, Luis

    2016-10-01

    Cumulative reports on antimicrobial susceptibility tests data are important for selecting empirical treatments, as an educational tool in programs on antimicrobial use, and for establishing breakpoints defining clinical categories. These reports should be based on data validated by clinical microbiologists using diagnostic samples (not surveillance samples). In order to avoid a bias derived from including several isolates obtained from the same patient, it is recommended that, for a defined period, only the first isolate is counted. A minimal number of isolates per species should be presented: a figure of >=30 isolates is statistically acceptable. The report is usually presented in a table format where, for each cell, information on clinically relevant microorganisms-antimicrobial agents is presented. Depending on particular needs, multiple tables showing data related to patients, samples, services or special pathogens can be prepared. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  13. Comparison of three standardized disc susceptibility testing methods for colistin.

    Science.gov (United States)

    Tan, Thean Yen; Ng, Lily Siew Yong

    2006-10-01

    With increasing antibiotic resistance in Gram-negative bacteria, the use of the polymyxins has increased in recent years. Antibiotic disc susceptibility testing remains the most widely used method in clinical laboratories, but there is very little data on the accuracy of disc testing methods for colistin. In this study, the accuracy of three standardized methods of disc susceptibility testing for colistin was compared with agar dilution. A total of 228 clinical isolates of Acinetobacter spp., Pseudomonas aeruginosa and Enterobacteriaceae were included in the study. Isolates were tested by agar dilution for susceptibility to colistin, and results were compared with those obtained by three disc susceptibility testing methods (product insert based on CLSI methodology, British BSAC and French SFM). Colistin displayed good activity against Acinetobacter spp., Klebsiella spp. and Escherichia coli (MIC(90) 2 mg/L) but was less active against P. aeruginosa (MIC(90) 4 mg/L) and Enterobacter spp. (MIC(90) >or= 128 mg/L). Totally, 81%, 79% and 89% of colistin-resistant isolates were falsely reported as susceptible when tested by the product insert, BSAC and SFM testing methods, respectively. There were no false-resistant results. Disc susceptibility testing methods are unreliable at detecting colistin resistance. Dilution methods should be the method of choice for susceptibility testing of colistin.

  14. Prediction of autism susceptibility genes based on association rules.

    Science.gov (United States)

    Gong, Lejun; Yan, Yunyang; Xie, Jianming; Liu, Hongde; Sun, Xiao

    2012-06-01

    Autism is a complex neuropsychiatric disorder with high heritability and an unclear etiology. The identification of key genes related to autism may elucidate its etiology. The current study provides an approach to predicting autism susceptibility genes. Genes are first extracted from the biomedical literature, and some autism susceptibility genes are then recognized as seeds by the prior knowledge. As candidates, the remaining genes are predicted by creating association rules between the seeds and candidates. In an evaluated data set, 27 autism susceptibility genes (type "Y") are extracted and 43 possible autism susceptibility genes (type "P") are predicted. The sum of "Y" and "P" genes accounts for 93.3% of the data set that are not contained in the typical database of autism susceptibility genes. Our approach can effectively extract and predict autism susceptibility genes from the biomedical literature. These predicted results complement the typical database of autism susceptibility genes. The web portal for the predicted results, which is freely available at http://biolab.hyit.edu.cn/ar, can be a valuable resource in studies of diseases related to genes. Copyright © 2012 Wiley Periodicals, Inc.

  15. Quantitative susceptibility mapping of small objects using volume constraints.

    Science.gov (United States)

    Liu, Saifeng; Neelavalli, Jaladhar; Cheng, Yu-Chung N; Tang, Jin; Mark Haacke, E

    2013-03-01

    Microbleeds have been implicated to play a role in many neurovascular and neurodegenerative diseases. The diameter of each microbleed has been used previously as a possible quantitative measure for grading microbleeds. We propose that magnetic susceptibility provides a new quantitative measure of extravasated blood. Recently, a Fourier-based method has been used that allows susceptibility quantification from phase images for any arbitrarily shaped structures. However, when very small objects, such as microbleeds, are considered, the accuracy of this susceptibility mapping method still remains to be evaluated. In this article, air bubbles and glass beads are taken as microbleed surrogates to evaluate the quantitative accuracy of the susceptibility mapping method. We show that when an object occupies only a few voxels, an estimate of the true volume of the object is necessary for accurate susceptibility quantification. Remnant errors in the quantified susceptibilities and their sources are evaluated. We show that quantifying magnetic moment, rather than the susceptibility of these small structures, may be a better and more robust alternative. Copyright © 2012 Wiley Periodicals, Inc.

  16. Novel density-based and hierarchical density-based clustering algorithms for uncertain data.

    Science.gov (United States)

    Zhang, Xianchao; Liu, Han; Zhang, Xiaotong

    2017-09-01

    Uncertain data has posed a great challenge to traditional clustering algorithms. Recently, several algorithms have been proposed for clustering uncertain data, and among them density-based techniques seem promising for handling data uncertainty. However, some issues like losing uncertain information, high time complexity and nonadaptive threshold have not been addressed well in the previous density-based algorithm FDBSCAN and hierarchical density-based algorithm FOPTICS. In this paper, we firstly propose a novel density-based algorithm PDBSCAN, which improves the previous FDBSCAN from the following aspects: (1) it employs a more accurate method to compute the probability that the distance between two uncertain objects is less than or equal to a boundary value, instead of the sampling-based method in FDBSCAN; (2) it introduces new definitions of probability neighborhood, support degree, core object probability, direct reachability probability, thus reducing the complexity and solving the issue of nonadaptive threshold (for core object judgement) in FDBSCAN. Then, we modify the algorithm PDBSCAN to an improved version (PDBSCANi), by using a better cluster assignment strategy to ensure that every object will be assigned to the most appropriate cluster, thus solving the issue of nonadaptive threshold (for direct density reachability judgement) in FDBSCAN. Furthermore, as PDBSCAN and PDBSCANi have difficulties for clustering uncertain data with non-uniform cluster density, we propose a novel hierarchical density-based algorithm POPTICS by extending the definitions of PDBSCAN, adding new definitions of fuzzy core distance and fuzzy reachability distance, and employing a new clustering framework. POPTICS can reveal the cluster structures of the datasets with different local densities in different regions better than PDBSCAN and PDBSCANi, and it addresses the issues in FOPTICS. Experimental results demonstrate the superiority of our proposed algorithms over the existing

  17. Bird remains from the Maastrichtian type area (Late Cretaceous)

    NARCIS (Netherlands)

    Dyke, Gareth J.; Schulp, A. S.; Jagt, J. W M

    2008-01-01

    Remains of Late Cretaceous birds are rare, which is especially true for Europe and the type area of the Maastrichtian Stage (southeast Netherlands, northeast Belgium) in particular. In the present paper, we record new remains (isolated tarsometatarsus and radius) that document the presence of both

  18. [Antimicrobial susceptibility in Chile 2012].

    Science.gov (United States)

    Cifuentes-D, Marcela; Silva, Francisco; García, Patricia; Bello, Helia; Briceño, Isabel; Calvo-A, Mario; Labarca, Jaime

    2014-04-01

    Bacteria antimicrobial resistance is an uncontrolled public health problem that progressively increases its magnitude and complexity. The Grupo Colaborativo de Resistencia, formed by a join of experts that represent 39 Chilean health institutions has been concerned with bacteria antimicrobial susceptibility in our country since 2008. In this document we present in vitro bacterial susceptibility accumulated during year 2012 belonging to 28 national health institutions that represent about 36% of hospital discharges in Chile. We consider of major importance to report periodically bacteria susceptibility so to keep the medical community updated to achieve target the empirical antimicrobial therapies and the control measures and prevention of the dissemination of multiresistant strains.

  19. Antibiotic susceptibility of Listeria monocytogenes in Argentina.

    Science.gov (United States)

    Prieto, Mónica; Martínez, Claudia; Aguerre, Lorena; Rocca, María Florencia; Cipolla, Lucía; Callejo, Raquel

    2016-02-01

    Listeria monocytogenes is the causative agent of listeriosis, a food-borne disease that mainly affects pregnant women, the elderly, and immunocompromised patients. The primary treatment of choice of listeriosis is the combination of ampicillin or penicillin G, with an aminoglycoside, classically gentamicin. The second-choice therapy for patients allergic to β-lactams is the combination of trimethoprim with a sulfonamide (such as co-trimoxazole). The aim of this study was to analyze the antimicrobial susceptibility profile of strains isolated from human infections and food during the last two decades in Argentina. The minimal inhibitory concentration (MIC) of 8 antimicrobial agents was determined for a set of 250 strains of L. monocytogenes isolated in Argentina during the period 1992-2012. Food-borne and human isolates were included in this study. The antibiotics tested were ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, erythromycin, gentamicin, penicillin G, tetracycline and rifampicin. Breakpoints for penicillin G, ampicillin and trimethoprim-sulfamethoxazole were those given in the CLSI for L. monocytogenes. CLSI criteria for staphylococci were applied to the other antimicrobial agents tested. Strains were serotyped by PCR, and confirmed by an agglutination method. Strains recovered from human listeriosis patients showed a prevalence of serotype 4b (71%), with the remaining 29% corresponding to serotype 1/2b. Serotypes among food isolates were distributed as 62% serotype 1/2b and 38% serotype 4b. All antimicrobial agents showed good activity. The strains of L. monocytogenes isolated in Argentina over a period of 20 years remain susceptible to antimicrobial agents, and that susceptibility pattern has not changed during this period. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  20. suitability of vitek 2 system in identification and susceptibility testing

    African Journals Online (AJOL)

    2014-04-01

    Apr 1, 2014 ... Infection of the bloodstream remains a life-threatening occurrence. Blood cultures and their microbiological analysis are essential for the diagnosis of this infection. (1,2). Rapid detection, identification, and antimicrobial susceptibility testing (AST) of bacteria from blood are crucial in patient management.

  1. pso.ATION AND ANTIMICROBIAL SUSCEPTIBILITY

    African Journals Online (AJOL)

    isolates vere made using standard methods, Antibiotic susceptibility tests against commonly prescribed ... Acute otitis media is rapid with short .... sensitivity tests. Antimicrobial susceptibility tests: The antimicrobial susceptibility patterns of major Gram positive and negative bacterial isolates obtained from clinical specimens.

  2. Impacts of global warming on phenology of spring leaf unfolding remain stable in the long run.

    Science.gov (United States)

    Wang, Huanjiong; Rutishauser, This; Tao, Zexing; Zhong, Shuying; Ge, Quansheng; Dai, Junhu

    2017-02-01

    The impact of spring temperature forcing on the timing of leaf unfolding of plants (temperature sensitivity, S T ) is one important indicator of how and to what degree plant species track climate change. Fu et al. (Nature 526:104-107, 2015) found that S T has significantly decreased from the 1980-1994 to the 1999-2013 period for seven mid-latitude tree species in Europe. However, long-term changes in S T over the past 60 years are still not clear. Here, using in situ observations of leaf unfolding for seven dominant European tree species, we analyze the temporal change in S T over decadal time scales extending the data series back to 1951. Our results demonstrate that S T shows no statistically significant change within shifting 30-year windows from 1951 to 2013 and remains stable between 1951-1980 and 1984-2013 (3.6 versus 3.7 days °C -1 ). This result suggests that the significant decrease in S T over the past 33 years could not be sustained when examining the trends of phenological responses in the long run. Therefore, we could not conclude that tree spring phenology advances will slow down in the future, and the S T changes in warming scenarios are still uncertain.

  3. Hypnotic susceptibility and dream characteristics.

    Science.gov (United States)

    Zamore, N; Barrett, D

    1989-11-01

    This study examined the relationship of hypnotic susceptibility to a variety of dream characteristics and types of dream content. A Dream Questionnaire was constructed synthesizing Gibson's dream inventory and Hilgard's theoretical conceptions of hypnosis. Employing the Harvard Group Scale of Hypnotic Susceptibility and the Field Inventory for evaluating hypnotic response, several dream dimensions correlated significantly with hypnotizability. For subjects as a whole, the strongest correlates were the frequency of dreams which they believed to be precognitive and out-of-body dreams. Ability to dream on a chosen topic also correlated significantly with hypnotic susceptibility for both genders. For females only, there was a negative correlation of hypnotic susceptibility to flying dreams. Absorption correlated positively with dream recall, ability to dream on a chosen topic, reports of conflict resolution in dreams, creative ideas occurring in dreams, amount of color in dreams, pleasantness of dreams, bizarreness of dreams, flying dreams and precognitive dreams.

  4. Ancestral susceptibility to colorectal cancer

    Czech Academy of Sciences Publication Activity Database

    Huhn, S.; Pardini, Barbara; Naccarati, Alessio; Vodička, Pavel (ed.); Hemminki, K.; Försti, A.

    2012-01-01

    Roč. 27, č. 2 (2012), s. 197-204 ISSN 0267-8357 R&D Projects: GA ČR GA310/07/1430; GA ČR GAP304/10/1286 Grant - others:EU FP7(XE) HEALTH-F4-2007-200767 Institutional research plan: CEZ:AV0Z50390512 Keywords : cancer susceptibility * molecular epidemiology * genetic susceptibility Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.500, year: 2012

  5. An Integrated Multiechelon Logistics Model with Uncertain Delivery Lead Time and Quality Unreliability

    Directory of Open Access Journals (Sweden)

    Ming-Feng Yang

    2016-01-01

    Full Text Available Nowadays, in order to achieve advantages in supply chain management, how to keep inventory in adequate level and how to enhance customer service level are two critical practices for decision makers. Generally, uncertain lead time and defective products have much to do with inventory and service level. Therefore, this study mainly aims at developing a multiechelon integrated just-in-time inventory model with uncertain lead time and imperfect quality to enhance the benefits of the logistics model. In addition, the Ant Colony Algorithm (ACA is established to determine the optimal solutions. Moreover, based on our proposed model and analysis, the ACA is more efficient than Particle Swarm Optimization (PSO and Lingo in SMEIJI model. An example is provided in this study to illustrate how production run and defective rate have an effect on system costs. Finally, the results of our research could provide some managerial insights which support decision makers in real-world operations.

  6. Stabilization of a Quadrotor With Uncertain Suspended Load Using Sliding Mode Control

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xu; Liu, Rui; Zhang, Jiucai; Zhang, Xiaoli

    2016-08-21

    The stability and trajectory control of a quadrotor carrying a suspended load with a fixed known mass has been extensively studied in recent years. However, the load mass is not always known beforehand in practical applications. This mass uncertainty brings uncertain disturbances to the quadrotor system, causing existing controllers to have a worse performance or to be collapsed. To improve the quadrotor's stability in this situation, we investigate the impacts of the uncertain load mass on the quadrotor. By comparing the simulation results of two controllers -- the proportional-derivative (PD) controller and the sliding mode controller (SMC) driven by a sliding mode disturbance of observer (SMDO), the quadrotor's performance is verified to be worse as the uncertainty increases. The simulation results also show a controller with stronger robustness against disturbances is better for practical applications.

  7. Location Model for Distribution Centers for Fulfilling Electronic Orders of Fresh Foods under Uncertain Demand

    Directory of Open Access Journals (Sweden)

    Hao Zhang

    2017-01-01

    Full Text Available The problem of locating distribution centers for delivering fresh food as a part of electronic commerce is a strategic decision problem for enterprises. This paper establishes a model for locating distribution centers that considers the uncertainty of customer demands for fresh goods in terms of time-sensitiveness and freshness. Based on the methodology of robust optimization in dealing with uncertain problems, this paper optimizes the location model in discrete demand probabilistic scenarios. In this paper, an improved fruit fly optimization algorithm is proposed to solve the distribution center location problem. An example is given to show that the proposed model and algorithm are robust and can effectively handle the complications caused by uncertain demand. The model proposed in this paper proves valuable both theoretically and practically in the selection of locations of distribution centers.

  8. Solutions to Uncertain Volterra Integral Equations by Fitted Reproducing Kernel Hilbert Space Method

    Directory of Open Access Journals (Sweden)

    Ghaleb Gumah

    2016-01-01

    Full Text Available We present an efficient modern strategy for solving some well-known classes of uncertain integral equations arising in engineering and physics fields. The solution methodology is based on generating an orthogonal basis upon the obtained kernel function in the Hilbert space W21a,b in order to formulate the analytical solutions in a rapidly convergent series form in terms of their α-cut representation. The approximation solution is expressed by n-term summation of reproducing kernel functions and it is convergent to the analytical solution. Our investigations indicate that there is excellent agreement between the numerical results and the RKHS method, which is applied to some computational experiments to demonstrate the validity, performance, and superiority of the method. The present work shows the potential of the RKHS technique in solving such uncertain integral equations.

  9. A Real Option Model with Uncertain, Sequential Investment and with Time to Build

    Directory of Open Access Journals (Sweden)

    Marcos Eugênio da Silva

    2005-12-01

    Full Text Available This article develops a real option model with uncertain and sequential investment and with time to build. The model includes options to entry and to exit the activity and addresses the maximization problem of a company in view of the investment opportunity. The differential equation of the asset is obtained by using dynamic programming and risk neutral evaluation. Particularly, for the construction period, the differential equation is partial and elliptical, which demands the use of numeric methods. The main results of the article are that (i with uncertain and sequential investment and with time to build, the waiting value, which creates a gap between the investment decision rule based on NPV and that based on a real option model, may not very significant and (ii the increase in uncertainty may anticipate the decision to investment.

  10. An Uncertain QFD Approach for the Strategic Management of Logistics Services

    Directory of Open Access Journals (Sweden)

    Shengpeng Yang

    2016-01-01

    Full Text Available Due to customers’ growing concern about logistics performances related to products, logistics service increasingly contributes to the core competence of an enterprise or product, which calls an appropriate tool to develop effective strategic actions to improve logistics performances and gain customer satisfaction. Therefore, an uncertain quality function deployment (QFD approach for selecting the most effective strategic actions in terms of efficiency to meet the customer requirements is developed in this paper, which integrates uncertainty theory into the traditional QFD methodology in order to rationally deal with imprecise information inherently involved in the QFD process. The framework and systematic procedures of the approach are presented in the context of logistics services. Specifically, the calculations for the prioritization of strategic actions are discussed in detail, in which uncertain variables are used to capture the linguistic judgements given by customers and experts. Applications of the proposed approach are presented as well for illustration.

  11. Non-probabilistic solution of uncertain vibration equation of large membranes using Adomian decomposition method.

    Science.gov (United States)

    Tapaswini, Smita; Chakraverty, S

    2014-01-01

    This paper proposes a new technique based on double parametric form of fuzzy numbers to handle the uncertain vibration equation for very large membrane for different particular cases. Uncertainties present in the initial condition and the wave velocity of free vibration are modelled through Gaussian convex normalised fuzzy set. Using the single parametric form of fuzzy number, the original fuzzy vibration equation is converted first to an interval fuzzy vibration equation. Next this equation is transformed to crisp form by applying double parametric form of fuzzy numbers. Finally the same governing equation is solved by Adomian decomposition method (ADM) symbolically to obtain the uncertain bounds. The present methods are very simple and effective. Obtained results are depicted in terms of plots to show the efficiency and powerfulness of the present analysis. Results obtained by the methods with new techniques are compared with existing results in special cases.

  12. Design of Robust AMB Controllers for Rotors Subjected to Varying and Uncertain Seal Forces

    DEFF Research Database (Denmark)

    Lauridsen, Jonas Skjødt; Santos, Ilmar

    2017-01-01

    This paper demonstrates the design and simulation results of model based controllers for AMB systems, subjectedto uncertain and changing dynamic seal forces. Specifically, a turbocharger with a hole-pattern seal mounted acrossthe balance piston is considered. The dynamic forces of the seal, which...... are dependent on the operational conditions,have a significant effect on the overall system dynamics. Furthermore, these forces are considered uncertain.The nominal and the uncertainty representation of the seal model are established using results from conventionalmodelling approaches, i.e. CFD and Bulkflow......, and experimental results. Three controllers are synthesized: I) AnH∞ controller based on nominal plant representation, II) A µ controller, designed to be robust against uncertaintiesin the dynamic seal model and III) a Linear Parameter Varying (LPV) controller, designed to provide a unifiedperformance over a large...

  13. A new smooth robust control design for uncertain nonlinear systems with non-vanishing disturbances

    Science.gov (United States)

    Xian, Bin; Zhang, Yao

    2016-06-01

    In this paper, we consider the control problem for a general class of nonlinear system subjected to uncertain dynamics and non-varnishing disturbances. A smooth nonlinear control algorithm is presented to tackle these uncertainties and disturbances. The proposed control design employs the integral of a nonlinear sigmoid function to compensate the uncertain dynamics, and achieve a uniformly semi-global practical asymptotic stable tracking control of the system outputs. A novel Lyapunov-based stability analysis is employed to prove the convergence of the tracking errors and the stability of the closed-loop system. Numerical simulation results on a two-link robot manipulator are presented to illustrate the performance of the proposed control algorithm comparing with the layer-boundary sliding mode controller and the robust of integration of sign of error control design. Furthermore, real-time experiment results for the attitude control of a quadrotor helicopter are also included to confirm the effectiveness of the proposed algorithm.

  14. Structure Identification of Uncertain Complex Networks Based on Anticipatory Projective Synchronization.

    Directory of Open Access Journals (Sweden)

    Liu Heng

    Full Text Available This paper investigates a method to identify uncertain system parameters and unknown topological structure in general complex networks with or without time delay. A complex network, which has uncertain topology and unknown parameters, is designed as a drive network, and a known response complex network with an input controller is designed to identify the drive network. Under the proposed input controller, the drive network and the response network can achieve anticipatory projective synchronization when the system is steady. Lyapunov theorem and Barbǎlat's lemma guarantee the stability of synchronization manifold between two networks. When the synchronization is achieved, the system parameters and topology in response network can be changed to equal with the parameters and topology in drive network. A numerical example is given to show the effectiveness of the proposed method.

  15. Uncertain multiobjective redundancy allocation problem of repairable systems based on artificial bee colony algorithm

    Directory of Open Access Journals (Sweden)

    Guo Jiansheng

    2014-12-01

    Full Text Available Based on the uncertainty theory, this paper is devoted to the redundancy allocation problem in repairable parallel-series systems with uncertain factors, where the failure rate, repair rate and other relative coefficients involved are considered as uncertain variables. The availability of the system and the corresponding designing cost are considered as two optimization objectives. A crisp multiobjective optimization formulation is presented on the basis of uncertainty theory to solve this resultant problem. For solving this problem efficiently, a new multiobjective artificial bee colony algorithm is proposed to search the Pareto efficient set, which introduces rank value and crowding distance in the greedy selection strategy, applies fast non-dominated sort procedure in the exploitation search and inserts tournament selection in the onlooker bee phase. It shows that the proposed algorithm outperforms NSGA-II greatly and can solve multiobjective redundancy allocation problem efficiently. Finally, a numerical example is provided to illustrate this approach.

  16. Multiobjective optimization in structural design with uncertain parameters and stochastic processes

    Science.gov (United States)

    Rao, S. S.

    1984-01-01

    The application of multiobjective optimization techniques to structural design problems involving uncertain parameters and random processes is studied. The design of a cantilever beam with a tip mass subjected to a stochastic base excitation is considered for illustration. Several of the problem parameters are assumed to be random variables and the structural mass, fatigue damage, and negative of natural frequency of vibration are considered for minimization. The solution of this three-criteria design problem is found by using global criterion, utility function, game theory, goal programming, goal attainment, bounded objective function, and lexicographic methods. It is observed that the game theory approach is superior in finding a better optimum solution, assuming the proper balance of the various objective functions. The procedures used in the present investigation are expected to be useful in the design of general dynamic systems involving uncertain parameters, stochastic process, and multiple objectives.

  17. Interpreting null results from measurements with uncertain correlations: an info-gap approach.

    Science.gov (United States)

    Ben-Haim, Yakov

    2011-01-01

    Null events—not detecting a pernicious agent—are the basis for declaring the agent is absent. Repeated nulls strengthen confidence in the declaration. However, correlations between observations are difficult to assess in many situations and introduce uncertainty in interpreting repeated nulls. We quantify uncertain correlations using an info-gap model, which is an unbounded family of nested sets of possible probabilities. An info-gap model is nonprobabilistic and entails no assumption about a worst case. We then evaluate the robustness, to uncertain correlations, of estimates of the probability of a null event. This is then the basis for evaluating a nonprobabilistic robustness-based confidence interval for the probability of a null. © 2010 Society for Risk Analysis.

  18. An efficient sampling algorithm for uncertain abnormal data detection in biomedical image processing and disease prediction.

    Science.gov (United States)

    Liu, Fei; Zhang, Xi; Jia, Yan

    2015-01-01

    In this paper, we propose a computer information processing algorithm that can be used for biomedical image processing and disease prediction. A biomedical image is considered a data object in a multi-dimensional space. Each dimension is a feature that can be used for disease diagnosis. We introduce a new concept of the top (k1,k2) outlier. It can be used to detect abnormal data objects in the multi-dimensional space. This technique focuses on uncertain space, where each data object has several possible instances with distinct probabilities. We design an efficient sampling algorithm for the top (k1,k2) outlier in uncertain space. Some improvement techniques are used for acceleration. Experiments show our methods' high accuracy and high efficiency.

  19. A Robust Service Selection Method Based on Uncertain QoS

    Directory of Open Access Journals (Sweden)

    Yanping Chen

    2016-01-01

    Full Text Available Nowadays, the number of Web services on the Internet is quickly increasing. Meanwhile, different service providers offer numerous services with the similar functions. Quality of Service (QoS has become an important factor used to select the most appropriate service for users. The most prominent QoS-based service selection models only take the certain attributes into account, which is an ideal assumption. In the real world, there are a large number of uncertain factors. In particular, at the runtime, QoS may become very poor or unacceptable. In order to solve the problem, a global service selection model based on uncertain QoS was proposed, including the corresponding normalization and aggregation functions, and then a robust optimization model adopted to transform the model. Experiment results show that the proposed method can effectively select services with high robustness and optimality.

  20. Multi-input robust saturation controller for uncertain linear time-invariant systems

    Science.gov (United States)

    Lim, Chae-Wook

    2007-03-01

    A robust saturation controller for the linear time-invariant (LTI) system involving both a control input's saturation and structured real parameter uncertainties was proposed in [C.W. Lim, Y. J. Park, S.J. Moon, Robust saturation controller for linear time-invariant system with structured real parameter uncertainties, Journal of Sound and Vibration 294 (1-2) (2006) 1-14]. This controller can also be applicable to the multi-input case. In this paper, the robust saturation controller is extended to the uncertain LTI system with multi-input and designed by introducing additional subsidiary setting parameters for each control input. An example is presented to show its application to multi-input uncertain LTI systems.

  1. Parameter Identification and Synchronization of Uncertain Chaotic Systems Based on Sliding Mode Observer

    Directory of Open Access Journals (Sweden)

    Li-lian Huang

    2013-01-01

    Full Text Available The synchronization of nonlinear uncertain chaotic systems is investigated. We propose a sliding mode state observer scheme which combines the sliding mode control with observer theory and apply it into the uncertain chaotic system with unknown parameters and bounded interference. Based on Lyapunov stability theory, the constraints of synchronization and proof are given. This method not only can realize the synchronization of chaotic systems, but also identify the unknown parameters and obtain the correct parameter estimation. Otherwise, the synchronization of chaotic systems with unknown parameters and bounded external disturbances is robust by the design of the sliding surface. Finally, numerical simulations on Liu chaotic system with unknown parameters and disturbances are carried out. Simulation results show that this synchronization and parameter identification has been totally achieved and the effectiveness is verified very well.

  2. Adaptive fuzzy sliding mode control for synchronization of uncertain fractional order chaotic systems

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Tsung-Chih, E-mail: tclin@fcu.edu.tw [Department of Electronic Engineering, Feng-Chia University, Taichung, Taiwan (China); Lee, Tun-Yuan [Department of Electronic Engineering, Feng-Chia University, Taichung, Taiwan (China); Balas, Valentina E. [Aurel Vlaicu University of Arad, B-dul Revolutiei 77, 310130 Arad (Romania)

    2011-10-15

    Highlights: > We study uncertain fractional order chaotic systems synchronization. > Lyapunov synthesis is used to derive control law and adaptive laws. > Based on sliding mode control, chattering phenomena in the control effort can be reduced. - Abstract: This paper deals with chaos synchronization between two different uncertain fractional order chaotic systems based on adaptive fuzzy sliding mode control (AFSMC). With the definition of fractional derivatives and integrals, a fuzzy Lyapunov synthesis approach is proposed to tune free parameters of the adaptive fuzzy controller on line by output feedback control law and adaptive law. Moreover, chattering phenomena in the control efforts can be reduced. The sliding mode design procedure not only guarantees the stability and robustness of the proposed AFSMC, but also the external disturbance on the synchronization error can be attenuated. The simulation example is included to confirm validity and synchronization performance of the advocated design methodology.

  3. Robust digital controllers for uncertain chaotic systems: A digital redesign approach

    Energy Technology Data Exchange (ETDEWEB)

    Ababneh, Mohammad [Department of Controls, FMC Kongsberg Subsea, FMC Energy Systems, Houston, TX 77067 (United States); Barajas-Ramirez, Juan-Gonzalo [CICESE, Depto. De Electronica y Telecomunicaciones, Ensenada, BC, 22860 (Mexico); Chen Guanrong [Centre for Chaos Control and Synchronization, Department of Electronic Engineering, City University of Hong Kong (China); Shieh, Leang S. [Department of Electrical and Computer Engineering, University of Houston, Houston, TX 77204-4005 (United States)

    2007-03-15

    In this paper, a new and systematic method for designing robust digital controllers for uncertain nonlinear systems with structured uncertainties is presented. In the proposed method, a controller is designed in terms of the optimal linear model representation of the nominal system around each operating point of the trajectory, while the uncertainties are decomposed such that the uncertain nonlinear system can be rewritten as a set of local linear models with disturbed inputs. Applying conventional robust control techniques, continuous-time robust controllers are first designed to eliminate the effects of the uncertainties on the underlying system. Then, a robust digital controller is obtained as the result of a digital redesign of the designed continuous-time robust controller using the state-matching technique. The effectiveness of the proposed controller design method is illustrated through some numerical examples on complex nonlinear systems--chaotic systems.

  4. Extreme-Scale Stochastic Particle Tracing for Uncertain Unsteady Flow Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hanqi; He, Wenbin; Seo, Sangmin; Shen, Han-Wei; Peterka, Tom

    2016-11-13

    We present an efficient and scalable solution to estimate uncertain transport behaviors using stochastic flow maps (SFM,) for visualizing and analyzing uncertain unsteady flows. SFM computation is extremely expensive because it requires many Monte Carlo runs to trace densely seeded particles in the flow. We alleviate the computational cost by decoupling the time dependencies in SFMs so that we can process adjacent time steps independently and then compose them together for longer time periods. Adaptive refinement is also used to reduce the number of runs for each location. We then parallelize over tasks—packets of particles in our design—to achieve high efficiency in MPI/thread hybrid programming. Such a task model also enables CPU/GPU coprocessing. We show the scalability on two supercomputers, Mira (up to 1M Blue Gene/Q cores) and Titan (up to 128K Opteron cores and 8K GPUs), that can trace billions of particles in seconds.

  5. Secure estimation, control and optimization of uncertain cyber-physical systems with applications to power networks

    Science.gov (United States)

    Taha, Ahmad Fayez

    Transportation networks, wearable devices, energy systems, and the book you are reading now are all ubiquitous cyber-physical systems (CPS). These inherently uncertain systems combine physical phenomena with communication, data processing, control and optimization. Many CPSs are controlled and monitored by real-time control systems that use communication networks to transmit and receive data from systems modeled by physical processes. Existing studies have addressed a breadth of challenges related to the design of CPSs. However, there is a lack of studies on uncertain CPSs subject to dynamic unknown inputs and cyber-attacks---an artifact of the insertion of communication networks and the growing complexity of CPSs. The objective of this dissertation is to create secure, computational foundations for uncertain CPSs by establishing a framework to control, estimate and optimize the operation of these systems. With major emphasis on power networks, the dissertation deals with the design of secure computational methods for uncertain CPSs, focusing on three crucial issues---(1) cyber-security and risk-mitigation, (2) network-induced time-delays and perturbations and (3) the encompassed extreme time-scales. The dissertation consists of four parts. In the first part, we investigate dynamic state estimation (DSE) methods and rigorously examine the strengths and weaknesses of the proposed routines under dynamic attack-vectors and unknown inputs. In the second part, and utilizing high-frequency measurements in smart grids and the developed DSE methods in the first part, we present a risk mitigation strategy that minimizes the encountered threat levels, while ensuring the continual observability of the system through available, safe measurements. The developed methods in the first two parts rely on the assumption that the uncertain CPS is not experiencing time-delays, an assumption that might fail under certain conditions. To overcome this challenge, networked unknown input

  6. Large-scale association analysis identifies new lung cancer susceptibility loci and heterogeneity in genetic susceptibility across histological subtypes

    DEFF Research Database (Denmark)

    McKay, James D; Hung, Rayjean J; Han, Younghun

    2017-01-01

    Although several lung cancer susceptibility loci have been identified, much of the heritability for lung cancer remains unexplained. Here 14,803 cases and 12,262 controls of European descent were genotyped on the OncoArray and combined with existing data for an aggregated genome-wide association ...

  7. Large-scale association analysis identifies new lung cancer susceptibility loci and heterogeneity in genetic susceptibility across histological subtypes

    NARCIS (Netherlands)

    Mckay, James D.; Hung, Rayjean J; Han, Younghun; Zong, Xuchen; Carreras-Torres, Robert; Christiani, David C.; Caporaso, Neil E.; Johansson, Mattias; Xiao, Xiangjun; Li, Yafang; Byun, Jinyoung; Dunning, Alison; Pooley, Karen A.; Qian, David C.; Ji, Xuemei; Liu, Geoffrey; Timofeeva, Maria N.; Bojesen, Stig E.; Wu, Xifeng; Le Marchand, Loic; Albanes, Demetrios; Bickeboeller, Heike; Aldrich, Melinda C.; Bush, William S.; Tardon, Adonina; Rennert, Gad; Teare, M. Dawn; Field, John K.; Kiemeney, Lambertus A.; Lazarus, Philip; Haugen, Aage; Lam, Stephen; Schabath, Matthew B.; Andrew, Angeline S.; Shen, Hongbing; Hong, Yun-Chul; Yuan, Jian-Min; Bertazzi, Pier Alberto; Pesatori, Angela C.; Ye, Yuanqing; Diao, Nancy; Su, Li; Zhang, Ruyang; Brhane, Yonathan; Leighl, Natasha; Johansen, Jakob S.; Mellemgaard, Anders; Saliba, Walid; Haiman, Christopher A.; Wilkens, Lynne R.; Fernandez-Somoano, Ana; Fernandez-Tardon, Guillermo; van der Heijden, Henricus F. M.; Kim, Jin Hee; Dai, Juncheng; Hu, Zhibin; Davies, Michael P. A.; Marcus, Michael W.; Brunnstrom, Hans; Manjer, Jonas; Melander, Olle; Muller, David C.; Overvad, Kim; Trichopoulou, Antonia; Tumino, Rosario; Doherty, Jennifer A.; Barnett, Matt P.; Chen, Chu; Goodman, Gary E.; Cox, Angela; Taylor, Fiona; Woll, Penella J.; Brueske, Irene; Wichmann, H. -Erich; Manz, Judith; Muley, Thomas R.; Risch, Angela; Rosenberger, Albert; Grankvist, Kjell; Johansson, Mikael; Shepherd, Frances A.; Tsao, Ming Sound; Arnold, Susanne M.; Haura, Eric B.; Bolca, Ciprian; Holcatova, Ivana; Janout, Vladimir; Kontic, Milica; Lissowska, Jolanta; Mukeria, Anush; Ognjanovic, Simona; Orlowski, Tadeusz M.; Scelo, Ghislaine; Swiatkowska, Beata; Zaridze, David; Bakke, Per; Skaug, Vidar; Zienolddiny, Shanbeh; Duell, Eric J.; Butler, Lesley M.; Koh, Woon-Puay; Gao, Yu-Tang; Houlston, Richard S.; McLaughlin, John; Stevens, Victoria L.; Joubert, Philippe; Lamontagne, Maxime; Nickle, David C.; Obeidat, Ma'en; Timens, Wim; Zhu, BL; Song, Lei; Kachuri, Linda; Artigas, Maria Soler; Tobin, Martin D.; Wain, Louise V.; Rafnar, Thorunn; Thorgeirsson, Thorgeir E.; Reginsson, Gunnar W.; Stefansson, Kari; Hancock, Dana B.; Bierut, Laura J.; Spitz, Margaret R.; Gaddis, Nathan C.; Lutz, Sharon M.; Gu, Fangyi; Johnson, Eric O.; Kamal, Ahsan; Pikielny, Claudio; Zhu, Dakai; Lindstroem, Sara; Jiang, Xia; Tyndale, Rachel F.; Chenevix-Trench, Georgia; Beesley, Jonathan; Bosse, Yohan; Chanock, Stephen; Brennan, Paul; Landi, Maria Teresa; Amos, Christopher I.

    Although several lung cancer susceptibility loci have been identified, much of the heritability for lung cancer remains unexplained. Here 14,803 cases and 12,262 controls of European descent were genotyped on the OncoArray and combined with existing data for an aggregated genomewide association

  8. Descriptions of the dental remains of Homo floresiensis

    National Research Council Canada - National Science Library

    KAIFU, YOUSUKE; KONO, REIKO T; SUTIKNA, THOMAS; SAPTOMO, E. WAHYU; JATMIKO; AWE, ROKUS DUE; BABA, HISAO

    2015-01-01

    Dental remains of Homo floresiensis excavated during 2002–2004 at Liang Bua, Flores, Indonesia, consist of one partial maxillary dentition, two nearly complete mandibular dentitions, and four isolated teeth...

  9. A Bayesian Framework for Remaining Useful Life Estimation

    Data.gov (United States)

    National Aeronautics and Space Administration — The estimation of remaining useful life (RUL) of a faulty component is at the center of system prognostics and health management. It gives operators a potent tool in...

  10. Phase processing for quantitative susceptibility mapping of regions with large susceptibility and lack of signal.

    Science.gov (United States)

    Fortier, Véronique; Levesque, Ives R

    2017-11-11

    Phase processing impacts the accuracy of quantitative susceptibility mapping (QSM). Techniques for phase unwrapping and background removal have been proposed and demonstrated mostly in brain. In this work, phase processing was evaluated in the context of large susceptibility variations (Δχ) and negligible signal, in particular for susceptibility estimation using the iterative phase replacement (IPR) algorithm. Continuous Laplacian, region-growing, and quality-guided unwrapping were evaluated. For background removal, Laplacian boundary value (LBV), projection onto dipole fields (PDF), sophisticated harmonic artifact reduction for phase data (SHARP), variable-kernel sophisticated harmonic artifact reduction for phase data (V-SHARP), regularization enabled sophisticated harmonic artifact reduction for phase data (RESHARP), and 3D quadratic polynomial field removal were studied. Each algorithm was quantitatively evaluated in simulation and qualitatively in vivo. Additionally, IPR-QSM maps were produced to evaluate the impact of phase processing on the susceptibility in the context of large Δχ with negligible signal. Quality-guided unwrapping was the most accurate technique, whereas continuous Laplacian performed poorly in this context. All background removal algorithms tested resulted in important phase inaccuracies, suggesting that techniques used for brain do not translate well to situations where large Δχ and no or low signal are expected. LBV produced the smallest errors, followed closely by PDF. Results suggest that quality-guided unwrapping should be preferred, with PDF or LBV for background removal, for QSM in regions with large Δχ and negligible signal. This reduces the susceptibility inaccuracy introduced by phase processing. Accurate background removal remains an open question. Magn Reson Med, 2017. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  11. On the Inefficiency of the Merit Order in Forward Electricity Markets with Uncertain Supply

    OpenAIRE

    Morales, Juan M.; Pineda, Salvador

    2015-01-01

    This paper provides insight on the economic inefficiency of the classical merit-order dispatch in electricity markets with uncertain supply. For this, we consider a power system whose operation is driven by a two-stage electricity market, with a forward and a real-time market. We analyze two different clearing mechanisms: a conventional one, whereby the forward and the balancing markets are independently cleared following a merit order, and a stochastic one, whereby both market stages are co-...

  12. Compete, coordinate, and cooperate: How to exploit uncertain environments with social interaction.

    Science.gov (United States)

    Schulze, Christin; Newell, Ben R

    2015-10-01

    Countless decisions, from the trivial to the crucial, are made in complex social contexts while facing uncertain consequences. Yet a large portion of decision making research focuses on either the effects of social interaction or the effects of environmental uncertainty by examining strategic games against others or individual games against nature. Drawing a connection between these approaches, the authors extend a standard individual choice paradigm to include social interaction with 1 other person. In this paradigm, 2 competing decision makers repeatedly select among 2 options, each offering a particular probability of a fixed payoff. When both players choose the same, correct option, the payoff is evenly split; when they choose different options, the player choosing the correct option receives the full payoff. The addition of this social dimension gives players an opportunity to fully exploit an uncertain environment via cooperation: By consistently choosing opposite options, two players can exploit the uncertain environment more effectively than a single player could. We present 2 experiments that manipulate environmental (Experiment 1) and social (Experiment 2) aspects of the paradigm. In Experiment 1, the outcome probabilities were either known or unknown to participants; in Experiment 2, participants' attention was drawn to individual or group gains by introducing either within- or between-group competition. Efficient cooperation did not emerge spontaneously in Experiment 1. Instead, most people probability maximized, mirroring the behavior observed in individual choice. By contrast, between--group competition in Experiment 2 facilitated efficient-but not always equitable--exploitation of uncertain environments. This work links the concepts of individual risky choice and strategic decision making under both environmental and social uncertainty. (c) 2015 APA, all rights reserved).

  13. Modelling resource contention in multi-robot task allocation problems with uncertain timing

    OpenAIRE

    Palmer, Andrew W.; Hill, Andrew J.; Scheding, Steven J.

    2016-01-01

    This paper proposes an analytical framework for modelling resource contention in multi-robot systems, where the travel times and task durations are uncertain. It uses several approximation methods to quickly and accurately calculate the probability distributions describing the times at which the tasks start and finish. Specific contributions include a method for calculating the probability of a set of independent normally distributed random events occurring in a given order, an upper bound on...

  14. Managing large-scale scientific hypotheses as uncertain and probabilistic data with support for predictive analytics

    OpenAIRE

    Gonçalves, Bernardo; Porto, Fabio

    2014-01-01

    The sheer scale of high-resolution raw data generated by simulation has motivated non-conventional approaches for data exploration referred as `immersive' and `in situ' query processing of the raw simulation data. Another step towards supporting scientific progress is to enable data-driven hypothesis management and predictive analytics out of simulation results. We present a synthesis method and tool for encoding and managing competing hypotheses as uncertain data in a probabilistic database ...

  15. Fuzzy model based adaptive synchronization of uncertain chaotic systems: Robust tracking control approach

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Eun-Ju; Hyun, Chang-Ho; Kim, Euntai [ICS Laboratory (B723), Department of Electrical and Electronic Engineering, Yonsei University, 134, Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of); Park, Mignon [ICS Laboratory (B723), Department of Electrical and Electronic Engineering, Yonsei University, 134, Shinchon-Dong, Seodaemun-Gu, Seoul 120-749 (Korea, Republic of)], E-mail: mignpark@yonsei.ac.kr

    2009-05-11

    This Letter presents fuzzy model-based robust tracking control for the adaptive synchronization of uncertain chaotic systems. Fuzzy model and adaptive algorithm are employed to present the unknown chaotic systems. H{sup {infinity}} and sliding mode control are combined to construct a robust tracking controller. The incorporated H{sup {infinity}} controller can attenuate the external disturbance and approximation error to any prescribed level. The proposed scheme guarantees that all the variables are bounded and the tracking error is compensated.

  16. Uncertain Risk Assessment of Knowledge Management: Based on Set Pair Analysis

    OpenAIRE

    Guibin Yang; Hongyu Gao

    2016-01-01

    Since the knowledge resource becomes an important part of enterprise resources, the knowledge management risks could significantly affect the enterprise operation efficiency. Controlling knowledge management risks is one of the enterprise management tasks; the managers and researchers focus on how to effectively evaluate the risks. This paper aims to solve this problem and puts forward an evaluation model of the uncertain risks of knowledge management. Based on set pair theory, a model is est...

  17. Skeletal sexing standards of human remains in Turkey

    OpenAIRE

    Gulhan, O

    2017-01-01

    The identification of victims involved in mass fatality incidents, as well as the identification of unknown individuals in criminal cases has become an increasingly important issue nowadays. Sex assessment represents a key point in forensic evaluations due to its significance in providing biological identity. Even though the availability of documented skeletal remains to forensic practitioners is a common practice in many countries, in Turkey, contemporary documented skeletal remains are not ...

  18. Method for recovering elemental silicon from cutting remains.

    OpenAIRE

    Ulset, Torgeir; Julrud, Stein; Cassayre, Laurent; Chamelot, Pierre; Massot, Laurent; Taxil, Pierre

    2008-01-01

    This invention relates to a method for recovering elemental silicon cutting remains containing silicon particles, wherein the method comprises manufacturing solid anodes from the cutting remains, arranging one or more manufactured anode (s) in an electrolytic cell with a molten salt electrolyte and one or more cathode (s), and applying a potential difference between the one or more anode (s) and cathode (s) to obtain an oxidation of metallic silicon in the one or more anode (s), tran...

  19. Stochastic finite element method for random harmonic analysis of composite plates with uncertain modal damping parameters

    Science.gov (United States)

    Sepahvand, K.

    2017-07-01

    Damping parameters of fiber-reinforced composite possess significant uncertainty due to the structural complexity of such materials. Considering the parameters as random variables, this paper uses the generalized polynomial chaos (gPC) expansion to capture the uncertainty in the damping and frequency response function of composite plate structures. A spectral stochastic finite element formulation for damped vibration analysis of laminate plates is employed. Experimental modal data for samples of plates is used to identify and realize the range and probability distributions of uncertain damping parameters. The constructed gPC expansions for the uncertain parameters are used as inputs to a deterministic finite element model to realize random frequency responses on a few numbers of collocation points generated in random space. The realizations then are employed to estimate the unknown deterministic functions of the gPC expansion approximating the responses. Employing modal superposition method to solve harmonic analysis problem yields an efficient sparse gPC expansion representing the responses. The results show while the responses are influenced by the damping uncertainties at the mid and high frequency ranges, the impact in low frequency modes can be safely ignored. Utilizing a few random collocation points, the method indicates also a very good agreement compared to the sampling-based Monte Carlo simulations with large number of realizations. As the deterministic finite element model serves as black-box solver, the procedure can be efficiently adopted to complex structural systems with uncertain parameters in terms of computational time.

  20. The Emergency Vehicle Routing Problem with Uncertain Demand under Sustainability Environments

    Directory of Open Access Journals (Sweden)

    Jin Qin

    2017-02-01

    Full Text Available The reasonable utilization of limited resources is critical to realize the sustainable developments. In the initial 72-h crucial rescue period after the disaster, emergency supplies have always been insufficient and the demands in the affected area have always been uncertain. In order to improve timeliness, utilization and sustainability of emergency service, the allocation of the emergency supplies and the emergency vehicle routes should be determined simultaneously. Assuming the uncertain demands follow normal distribution, an optimization model for the emergency vehicle routing, by considering the insufficient supplies and the uncertain demands, is developed. The objective function is applied to minimize the total costs, including the penalty costs induced by more or less supplies than the actual demands at all demand points, as well as the constraints of the time windows and vehicle load capacity taken into account. In more details, a solution method for the model, based on the genetic algorithm, is proposed, which solves the problem in two stages. A numerical example is presented to demonstrate the efficiency and validity of the proposed model and algorithm.

  1. Exploring the concept of uncertain fertility, reproduction and motherhood after cancer in young adult women.

    Science.gov (United States)

    Halliday, Lesley E; Boughton, Maureen A

    2011-06-01

    Exploring the concept of uncertain fertility, reproduction and motherhood after cancer in young adult women The topics of uncertainty in illness and infertility--as separate entities--are well covered and critiqued in the literature. Conversely, no research has been identified that specifically relates to the uncertain fertility, reproduction and motherhood challenges faced by young women after cancer. Therefore, there has been no opportunity to extend understanding, adequately acknowledge or effectively manage the needs of young women who may face unique reproductive uncertainties after cancer. The objective of this article is to provide a descriptive review of the literature and present what is currently known about uncertainty in the context of cancer and in relation to fertility, reproduction and motherhood. This article sets out the need for an increased research focus into this aspect of cancer survivorship to minimise the unique psychosocial challenges these women often face. Raising awareness and acknowledging the significance and impact of uncertain reproductive capacity on younger women's psychosocial health will aid cancer co-ordinators, nurses and other health professionals to formulate and deliver timely and appropriate education, management and support. © 2011 Blackwell Publishing Ltd.

  2. Multiple Attribute Decision Making Based on Cross-Evaluation with Uncertain Decision Parameters

    Directory of Open Access Journals (Sweden)

    Tao Ding

    2016-01-01

    Full Text Available Multiple attribute decision making (MADM problem is one of the most common and popular research fields in the theory of decision science. A variety of methods have been proposed to deal with such problems. Nevertheless, many of them assumed that attribute weights are determined by different types of additional preference information which will result in subjective decision making. In order to solve such problems, in this paper, we propose a novel MADM approach based on cross-evaluation with uncertain parameters. Specifically, the proposed approach assumes that all attribute weights are uncertain. It can overcome the drawback in prior research that the alternatives’ ranking may be determined by a single attribute with an overestimated weight. In addition, the proposed method can also balance the mean and deviation of each alternative’s cross-evaluation score to guarantee the stability of evaluation. Then, this method is extended to a more generalized situation where the attribute values are also uncertain. Finally, we illustrate the applicability of the proposed method by revisiting two reported studies and by a case study on the selection of community service companies in the city of Hefei in China.

  3. Optimizing Bus Frequencies under Uncertain Demand: Case Study of the Transit Network in a Developing City

    Directory of Open Access Journals (Sweden)

    Zhengfeng Huang

    2013-01-01

    Full Text Available Various factors can make predicting bus passenger demand uncertain. In this study, a bilevel programming model for optimizing bus frequencies based on uncertain bus passenger demand is formulated. There are two terms constituting the upper-level objective. The first is transit network cost, consisting of the passengers’ expected travel time and operating costs, and the second is transit network robustness performance, indicated by the variance in passenger travel time. The second term reflects the risk aversion of decision maker, and it can make the most uncertain demand be met by the bus operation with the optimal transit frequency. With transit link’s proportional flow eigenvalues (mean and covariance obtained from the lower-level model, the upper-level objective is formulated by the analytical method. In the lower-level model, the above two eigenvalues are calculated by analyzing the propagation of mean transit trips and their variation in the optimal strategy transit assignment process. The genetic algorithm (GA used to solve the model is tested in an example network. Finally, the model is applied to determining optimal bus frequencies in the city of Liupanshui, China. The total cost of the transit system in Liupanshui can be reduced by about 6% via this method.

  4. Adaptive Fault-Tolerant Control of Uncertain Nonlinear Large-Scale Systems With Unknown Dead Zone.

    Science.gov (United States)

    Chen, Mou; Tao, Gang

    2016-08-01

    In this paper, an adaptive neural fault-tolerant control scheme is proposed and analyzed for a class of uncertain nonlinear large-scale systems with unknown dead zone and external disturbances. To tackle the unknown nonlinear interaction functions in the large-scale system, the radial basis function neural network (RBFNN) is employed to approximate them. To further handle the unknown approximation errors and the effects of the unknown dead zone and external disturbances, integrated as the compounded disturbances, the corresponding disturbance observers are developed for their estimations. Based on the outputs of the RBFNN and the disturbance observer, the adaptive neural fault-tolerant control scheme is designed for uncertain nonlinear large-scale systems by using a decentralized backstepping technique. The closed-loop stability of the adaptive control system is rigorously proved via Lyapunov analysis and the satisfactory tracking performance is achieved under the integrated effects of unknown dead zone, actuator fault, and unknown external disturbances. Simulation results of a mass-spring-damper system are given to illustrate the effectiveness of the proposed adaptive neural fault-tolerant control scheme for uncertain nonlinear large-scale systems.

  5. Formation Learning Control of Multiple Autonomous Underwater Vehicles With Heterogeneous Nonlinear Uncertain Dynamics.

    Science.gov (United States)

    Yuan, Chengzhi; Licht, Stephen; He, Haibo

    2017-09-26

    In this paper, a new concept of formation learning control is introduced to the field of formation control of multiple autonomous underwater vehicles (AUVs), which specifies a joint objective of distributed formation tracking control and learning/identification of nonlinear uncertain AUV dynamics. A novel two-layer distributed formation learning control scheme is proposed, which consists of an upper-layer distributed adaptive observer and a lower-layer decentralized deterministic learning controller. This new formation learning control scheme advances existing techniques in three important ways: 1) the multi-AUV system under consideration has heterogeneous nonlinear uncertain dynamics; 2) the formation learning control protocol can be designed and implemented by each local AUV agent in a fully distributed fashion without using any global information; and 3) in addition to the formation control performance, the distributed control protocol is also capable of accurately identifying the AUVs' heterogeneous nonlinear uncertain dynamics and utilizing experiences to improve formation control performance. Extensive simulations have been conducted to demonstrate the effectiveness of the proposed results.

  6. In vitro susceptibilities of Brucella melitensis isolates to eleven antibiotics

    Directory of Open Access Journals (Sweden)

    Loukaides Feidias

    2006-10-01

    Full Text Available Abstract Background Brucellosis is an endemic disease present in many countries worldwide, but it is rare in Europe and North America. Nevertheless brucella is included in the bacteria potentially used for bioterrorism. The aim of this study was the investigation of the antibiotic susceptibility profile of brucella isolates from areas of the eastern Mediterranean where it has been endemic. Methods The susceptibilities of 74 Brucella melitensis isolates derived from clinical samples (57 and animal products (17 were tested in vitro. The strains originate from Crete (59, Cyprus (10, and Syria (5. MICs of tetracycline, rifampicin, streptomycin, gentamicin, norfloxacin, ciprofloxacin, levofloxacin, trimethoprim/sulfamethoxazole, ampicillin, amoxicillin/clavulanic acid, and erythromycin were detected by E-test method. The NCCLS criteria for slow growing bacteria were considered to interpret the results. Results All the isolates were susceptible to tetracycline, streptomycin, gentamicin, ciprofloxacin, norfloxacin, and levofloxacin. Two isolates presented reduced susceptibility to rifampicin (MIC value: 1.5 mg/l and eight to SXT (MIC values: 0.75–1.5 mg/l. Erythromycin had the highest (4 mg/l MIC90value and both norfloxacin and erythromycin the highest (1.5 mg/l MIC50 value. Conclusion Brucella isolates remain susceptible in vitro to most antibiotics used for treatment of brucellosis. The establishment of a standardized antibiotic susceptibility method for Brucella spp would be useful for resistance determination in these bacteria and possible evaluation of bioterorism risks.

  7. Event-Sampled Direct Adaptive NN Output- and State-Feedback Control of Uncertain Strict-Feedback System.

    Science.gov (United States)

    Szanto, Nathan; Narayanan, Vignesh; Jagannathan, Sarangapani

    2017-04-12

    In this paper, a novel event-triggered implementation of a tracking controller for an uncertain strict-feedback system is presented. Neural networks (NNs) are utilized in the backstepping approach to design a control input by approximating unknown dynamics of the strict-feedback nonlinear system with event-sampled inputs. The system state vector is assumed to be unknown and an NN observer is used to estimate the state vector. By using the estimated state vector and backstepping design approach, an event-sampled controller is introduced. As part of the controller design, first, input-to-state-like stability for a continuously sampled controller that has been injected with bounded measurement errors is demonstrated, and subsequently, an event-execution control law is derived, such that the measurement errors are guaranteed to remain bounded. Lyapunov theory is used to demonstrate that the tracking errors, the observer estimation errors, and the NN weight estimation errors for each NN are locally uniformly ultimately bounded in the presence bounded disturbances, NN reconstruction errors, as well as errors introduced by event sampling. Simulation results are provided to illustrate the effectiveness of the proposed controllers.

  8. An Optimal Decision Model of Production-Inventory with MTS and ATO Hybrid Model Considering Uncertain Demand

    Directory of Open Access Journals (Sweden)

    Dezhi Zhang

    2015-01-01

    Full Text Available This paper presents an optimization decision model for a production system that comprises the hybrid make-to-stock/assemble-to-order (MTS/ATO organization mode with demand uncertainty, which can be described as a two-stage decision model. In the first decision stage (i.e., before acquiring the actual demand information of the customer, we have studied the optimal quantities of the finished products and components, while in the second stage (i.e., after acquiring the actual demand information of the customer, we have made the optimal decision on the assignment of components to satisfy the remaining demand. The optimal conditions on production and inventory decision are deduced, as well as the bounds of the total procurement quantity of the components in the ATO phase and final products generated in the MTS phase. Finally, an example is given to illustrate the above optimal model. The findings are shown as follows: the hybrid MTS and ATO production system reduces uncertain demand risk by arranging MTS phase and ATO phase reasonably and improves the expected profit of manufacturer; applying the strategy of component commonality can reduce the total inventory level, as well as the risk induced by the lower accurate demand forecasting.

  9. Forensic considerations when dealing with incinerated human dental remains.

    Science.gov (United States)

    Reesu, Gowri Vijay; Augustine, Jeyaseelan; Urs, Aadithya B

    2015-01-01

    Establishing the human dental identification process relies upon sufficient post-mortem data being recovered to allow for a meaningful comparison with ante-mortem records of the deceased person. Teeth are the most indestructible components of the human body and are structurally unique in their composition. They possess the highest resistance to most environmental effects like fire, desiccation, decomposition and prolonged immersion. In most natural as well as man-made disasters, teeth may provide the only means of positive identification of an otherwise unrecognizable body. It is imperative that dental evidence should not be destroyed through erroneous handling until appropriate radiographs, photographs, or impressions can be fabricated. Proper methods of physical stabilization of incinerated human dental remains should be followed. The maintenance of integrity of extremely fragile structures is crucial to the successful confirmation of identity. In such situations, the forensic dentist must stabilise these teeth before the fragile remains are transported to the mortuary to ensure preservation of possibly vital identification evidence. Thus, while dealing with any incinerated dental remains, a systematic approach must be followed through each stage of evaluation of incinerated dental remains to prevent the loss of potential dental evidence. This paper presents a composite review of various studies on incinerated human dental remains and discusses their impact on the process of human identification and suggests a step by step approach. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  10. Comparative susceptibility of bemisia tabaci to imidacloprid in field- and laboratory-based bioassays

    Science.gov (United States)

    Bemisia tabaci biotype B is a resistance-prone pest of protected and open agriculture. Systemic uptake bioassays used in resistance monitoring programs have provided important information on susceptibility to neonicotinoid insecticides, but have remained decoupled from field performance. Simultaneou...

  11. Combination of statistical and physically based methods to assess shallow slide susceptibility at the basin scale

    Science.gov (United States)

    Oliveira, Sérgio C.; Zêzere, José L.; Lajas, Sara; Melo, Raquel

    2017-07-01

    Approaches used to assess shallow slide susceptibility at the basin scale are conceptually different depending on the use of statistical or physically based methods. The former are based on the assumption that the same causes are more likely to produce the same effects, whereas the latter are based on the comparison between forces which tend to promote movement along the slope and the counteracting forces that are resistant to motion. Within this general framework, this work tests two hypotheses: (i) although conceptually and methodologically distinct, the statistical and deterministic methods generate similar shallow slide susceptibility results regarding the model's predictive capacity and spatial agreement; and (ii) the combination of shallow slide susceptibility maps obtained with statistical and physically based methods, for the same study area, generate a more reliable susceptibility model for shallow slide occurrence. These hypotheses were tested at a small test site (13.9 km2) located north of Lisbon (Portugal), using a statistical method (the information value method, IV) and a physically based method (the infinite slope method, IS). The landslide susceptibility maps produced with the statistical and deterministic methods were combined into a new landslide susceptibility map. The latter was based on a set of integration rules defined by the cross tabulation of the susceptibility classes of both maps and analysis of the corresponding contingency tables. The results demonstrate a higher predictive capacity of the new shallow slide susceptibility map, which combines the independent results obtained with statistical and physically based models. Moreover, the combination of the two models allowed the identification of areas where the results of the information value and the infinite slope methods are contradictory. Thus, these areas were classified as uncertain and deserve additional investigation at a more detailed scale.

  12. Combination of statistical and physically based methods to assess shallow slide susceptibility at the basin scale

    Directory of Open Access Journals (Sweden)

    S. C. Oliveira

    2017-07-01

    Full Text Available Approaches used to assess shallow slide susceptibility at the basin scale are conceptually different depending on the use of statistical or physically based methods. The former are based on the assumption that the same causes are more likely to produce the same effects, whereas the latter are based on the comparison between forces which tend to promote movement along the slope and the counteracting forces that are resistant to motion. Within this general framework, this work tests two hypotheses: (i although conceptually and methodologically distinct, the statistical and deterministic methods generate similar shallow slide susceptibility results regarding the model's predictive capacity and spatial agreement; and (ii the combination of shallow slide susceptibility maps obtained with statistical and physically based methods, for the same study area, generate a more reliable susceptibility model for shallow slide occurrence. These hypotheses were tested at a small test site (13.9 km2 located north of Lisbon (Portugal, using a statistical method (the information value method, IV and a physically based method (the infinite slope method, IS. The landslide susceptibility maps produced with the statistical and deterministic methods were combined into a new landslide susceptibility map. The latter was based on a set of integration rules defined by the cross tabulation of the susceptibility classes of both maps and analysis of the corresponding contingency tables. The results demonstrate a higher predictive capacity of the new shallow slide susceptibility map, which combines the independent results obtained with statistical and physically based models. Moreover, the combination of the two models allowed the identification of areas where the results of the information value and the infinite slope methods are contradictory. Thus, these areas were classified as uncertain and deserve additional investigation at a more detailed scale.

  13. Susceptibility Genes in Thyroid Autoimmunity

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Ban

    2005-01-01

    Full Text Available The autoimmune thyroid diseases (AITD are complex diseases which are caused by an interaction between susceptibility genes and environmental triggers. Genetic susceptibility in combination with external factors (e.g. dietary iodine is believed to initiate the autoimmune response to thyroid antigens. Abundant epidemiological data, including family and twin studies, point to a strong genetic influence on the development of AITD. Various techniques have been employed to identify the genes contributing to the etiology of AITD, including candidate gene analysis and whole genome screening. These studies have enabled the identification of several loci (genetic regions that are linked with AITD, and in some of these loci, putative AITD susceptibility genes have been identified. Some of these genes/loci are unique to Graves' disease (GD and Hashimoto's thyroiditis (HT and some are common to both the diseases, indicating that there is a shared genetic susceptibility to GD and HT. The putative GD and HT susceptibility genes include both immune modifying genes (e.g. HLA, CTLA-4 and thyroid specific genes (e.g. TSHR, Tg. Most likely, these loci interact and their interactions may influence disease phenotype and severity.

  14. On random age and remaining lifetime for populations of items

    DEFF Research Database (Denmark)

    Finkelstein, M.; Vaupel, J.

    2015-01-01

    We consider items that are incepted into operation having already a random (initial) age and define the corresponding remaining lifetime. We show that these lifetimes are identically distributed when the age distribution is equal to the equilibrium distribution of the renewal theory. Then we...

  15. Holocene insect remains from south-western Greenland

    DEFF Research Database (Denmark)

    Bøcher, Jens Jensenius; Bennike, Ole; Wagner, Bernd

    2012-01-01

    Remains of plants and invertebrates from Holocene deposits in south-western Greenland include a number of insect fragments from Heteroptera and Coleoptera. Some of the finds extend the known temporal range of the species considerably back in time, and one of the taxa has not previously been found...... of terrestrial insects complement the scarce fossil Greenland record of the species concerned....

  16. Remaining childless : Causes and consequences from a life course perspective

    NARCIS (Netherlands)

    Keizer, R.

    2010-01-01

    Little is know about childless individuals in the Netherlands, although currently one out of every five Dutch individuals remains childless. Who are they? How did they end up being childless? How and to what extent are their life outcomes influenced by their childlessness? By focusing on individual

  17. Predicting the Remaining Useful Life of Rolling Element Bearings

    DEFF Research Database (Denmark)

    Hooghoudt, Jan Otto; Jantunen, E; Yi, Yang

    2017-01-01

    Condition monitoring of rolling element bearings is of vital importance in order to keep the industrial wheels running. In wind industry this is especially important due to the challenges in practical maintenance. The paper presents an attempt to improve the capability of prediction of remaining...

  18. Remaining a Nonparticipant in a Cooperative Group Setting.

    Science.gov (United States)

    Deardoff, Richard

    1996-01-01

    A high school history teacher of gifted students examined difficulties in establishing cooperative groups when members changed frequently. Student interviews and surveys indicated that some students were happy to remain nonparticipants in any group. Participation was less a factor of group makeup than a factor of student opinion about grades.…

  19. Dinosaur remains from the type Maastrichtian: An update

    NARCIS (Netherlands)

    Weishampel, David B.; Mulder, Eric W A; Dortangs, Rudi W.; Jagt, John W M; Jianu, Coralia Maria; Kuypers, Marcel M M; Peeters, Hans H G; Schulp, Anne S.

    1999-01-01

    Isolated cranial and post-cranial remains of hadrosaurid dinosaurs have been collected from various outcrops in the type area of the Maastrichtian stage during the last few years. In the present contribution, dentary and maxillary teeth are recorded from the area for the first time. Post-cranial

  20. Ancient DNA in human bone remains from Pompeii archaeological site.

    Science.gov (United States)

    Cipollaro, M; Di Bernardo, G; Galano, G; Galderisi, U; Guarino, F; Angelini, F; Cascino, A

    1998-06-29

    aDNA extraction and amplification procedures have been optimized for Pompeian human bone remains whose diagenesis has been determined by histological analysis. Single copy genes amplification (X and Y amelogenin loci and Y specific alphoid repeat sequences) have been performed and compared with anthropometric data on sexing.

  1. The Workers' Value of the Remaining Employment Contract Duration

    NARCIS (Netherlands)

    Ommeren, van Jos; Hazans, Mihails

    2005-01-01

    This paper introduces and applies a method for estimating workers' marginal willingness to pay for job attributes employing data on job search activity. Worker's willingness to pay for the remaining duration of the employment contract is derived. We provide evidence that workers attach substantial

  2. Robotics to Enable Older Adults to Remain Living at Home

    Directory of Open Access Journals (Sweden)

    Alan J. Pearce

    2012-01-01

    Full Text Available Given the rapidly ageing population, interest is growing in robots to enable older people to remain living at home. We conducted a systematic review and critical evaluation of the scientific literature, from 1990 to the present, on the use of robots in aged care. The key research questions were as follows: (1 what is the range of robotic devices available to enable older people to remain mobile, independent, and safe? and, (2 what is the evidence demonstrating that robotic devices are effective in enabling independent living in community dwelling older people? Following database searches for relevant literature an initial yield of 161 articles was obtained. Titles and abstracts of articles were then reviewed by 2 independent people to determine suitability for inclusion. Forty-two articles met the criteria for question 1. Of these, 4 articles met the criteria for question 2. Results showed that robotics is currently available to assist older healthy people and people with disabilities to remain independent and to monitor their safety and social connectedness. Most studies were conducted in laboratories and hospital clinics. Currently limited evidence demonstrates that robots can be used to enable people to remain living at home, although this is an emerging smart technology that is rapidly evolving.

  3. Five reasons why South African librarianship remains untransformed ...

    African Journals Online (AJOL)

    ... librarianship remains untransformed. These reasons are the result of misunderstandings by librarians about the historical process, social change, political change, professional change and the intellectual roles of librarians. Suggestions for dealing with these misunderstandings are provided. (Innovation: 2002 25: 27-36) ...

  4. Molecular genetic identification of skeletal remains of apartheid ...

    African Journals Online (AJOL)

    The Truth and Reconciliation Commission made significant progress in examining abuses committed during the apartheid era in South Africa. Despite information revealed by the commission, a large number of individuals remained missing when the commission closed its proceedings. This provided the impetus for the ...

  5. The experiences of remaining nurse tutors during the transformation ...

    African Journals Online (AJOL)

    The transformation of public services and education in South Africa is part of the political and socioeconomic transition to democracy. Changes are occurring in every fi eld, including that of the health services. A qualitative study was undertaken to investigate the experiences of the remaining nurse tutors at a school of ...

  6. The treatment of human remains | Satyapal | South African Journal ...

    African Journals Online (AJOL)

    Concerns regarding treatment of the dead in scientific and public arenas, issues related to consent, respect for human dignity, scientific integrity, societal expectations, and why treatment of cadavers are ethically significant are highlighted. The display of human remains claimed as 'edutainment' or 'anatomy art' in Body ...

  7. Collegial Climate and Novice Teachers' Intent to Remain Teaching

    Science.gov (United States)

    Pogodzinski, Ben; Youngs, Peter; Frank, Kenneth A.

    2013-01-01

    Using survey data from novice teachers across 99 schools, we estimated multilevel regressions to identify the association between novices' intent to remain teaching within their schools and their perceptions of the collegial climate. The results suggest that novice teachers who perceive a more positive collegial climate marked by higher degrees…

  8. Magnetic susceptibility as a biosignature in stromatolites

    Science.gov (United States)

    Petryshyn, Victoria A.; Corsetti, Frank A.; Frantz, Carie M.; Lund, Steve P.; Berelson, William M.

    2016-03-01

    Microbialites have long been a focus of study in geobiology because they are macroscopic sedimentary records of the activities of microscopic organisms. However, abiotic processes can result in microbialite-like morphologies. Developing robust tools for substantiating the biogenicity of putative microbialites remains an important challenge. Here, we report a new potential biosignature based on the detrital magnetic mineral component present in nearly all sedimentary rocks. Detrital grains falling onto a hard, abiogenic, chemically precipitated structure would be expected to roll off surfaces at high incline angles. Thus, the distribution of grains in an abiogenic microbialite should exhibit a dependence on the dip angle along laminae. In contrast, a microbialite formed by the active trapping and binding of detrital grains by microorganisms could exhibit a distribution of detrital grains significantly less dependent on the dip angle of the laminae. However, given that most ancient stromatolites are micritic (composed of carbonate mud), tracking detrital grains vs. precipitated carbonate is not straightforward. Recent advances in our ability to measure miniscule magnetic fields open up the possibility to map magnetic susceptibility as a tracer of detrital grains in stromatolites. In abiogenic carbonate precipitation experiments, magnetic susceptibility fell to zero when the growth surface was inclined above 30° (the angle at which grains rolled off). In cyanobacterial mat experiments, even vertically inclined mats held magnetic material. The results indicate that cyanobacterial mats trap and bind small grains more readily than abiogenic carbonate precipitates alone. A variety of stromatolites of known and unknown biogenicity were then analyzed. Tested stromatolites span many different ages (Eocene to Holocene) and depositional environments (hot springs, lakes), and compositional forms (micritic, sparry crusts, etc.). The results were consistent with the laboratory

  9. Inherited susceptibility and radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Little, J.B. [Harvard School of Public Health, Boston, MA (United States)

    1997-03-01

    There is continuing concern that some people in the general population may have genetic makeups that place them at particularly high risk for radiation-induced cancer. The existence of such a susceptible subpopulation would have obvious implications for the estimation of risks of radiation exposure. Although it has been long known that familial aggregations of cancer do sometimes occur, recent evidence suggests that a general genetic predisposition to cancer does not exist; most cancers occur sporadically. On the other hand, nearly 10% of the known Mendelian genetic disorders are associated with cancer. A number of these involve a familial predisposition to cancer, and some are characterized by an enhanced susceptibility to the induction of cancer by various physical and chemical carcinogens, including ionizing radiation. Such increased susceptibility will depend on several factors including the frequency of the susceptibility gene in the population and its penetrance, the strength of the predisposition, and the degree to which the cancer incidence in susceptible individuals may be increased by the carcinogen. It is now known that these cancer-predisposing genes may be responsible not only for rare familial cancer syndromes, but also for a proportion of the common cancers. Although the currently known disorders can account for only a small fraction of all cancers, they serve as models for genetic predisposition to carcinogen-induced cancer in the general population. In the present report, the author describes current knowledge of those specific disorders that are associated with an enhanced predisposition to radiation-induced cancer, and discusses how this knowledge may bear on the susceptibility to radiation-induced cancer in the general population and estimates of the risk of radiation exposure.

  10. pitting corrosion susceptibility pitting corrosion susceptibility of aisi ...

    African Journals Online (AJOL)

    eobe

    Abstract. The susceptibility of austenitic (AISI 301) stainless steel to pitting corrosion was evaluated in sodium chloride. (NaCl) solutions ... AISI 301 steel suffers from pitting corrosion in all the investigated solutions. AISI 301 steel suffers from ..... [1] Ijeomah, M.N.C. Elements of Corrosion and Protection. Theory, Auto Century ...

  11. Magnetic Susceptability Measurements in Superconductors

    Science.gov (United States)

    Kim, Jason; Mallory, Kendall; Seim, Ryan

    2000-04-01

    A new undergraduate research facility in magnetic susceptability measurements on superconductors is being developed at the University of Northern Colorado. Initial data measurements of the magnetic susceptability of various superconductors will be presented. These measurements were obtained with a liquid helium/nitrogen dewar that was reassembled for use in this project. The cryostat consists of two separate dewars, the first of which contains liquid nitrogen, the second, liquid helium. The liquid nitrogen dewar is used to keep the helium bath from evaporating off too quickly. Data on the evaporation rates of the two liquids will also be presented.

  12. Time-optimal path planning in uncertain flow fields using ensemble method

    KAUST Repository

    Wang, Tong

    2016-01-06

    An ensemble-based approach is developed to conduct time-optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where a set deterministic predictions is used to model and quantify uncertainty in the predictions. In the operational setting, much about dynamics, topography and forcing of the ocean environment is uncertain, and as a result a single path produced by a model simulation has limited utility. To overcome this limitation, we rely on a finitesize ensemble of deterministic forecasts to quantify the impact of variability in the dynamics. The uncertainty of flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each the resulting realizations of the uncertain current field, we predict the optimal path by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of sampling strategy, and develop insight into extensions dealing with regional or general circulation models. In particular, the ensemble method enables us to perform a statistical analysis of travel times, and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.

  13. Neural correlates of uncertain decision making: ERP evidence from the Iowa Gambling Task

    Directory of Open Access Journals (Sweden)

    Ji-fang eCui

    2013-11-01

    Full Text Available In our daily life, it is very common to make decisions in uncertain situations. The Iowa Gambling Task (IGT has been widely used in laboratory studies because of its good simulation of uncertainty in real life activities. The present study aimed to examine the neural correlates of uncertain decision making with the IGT. Twenty-six university students completed this study. An adapted IGT was administered to them, and the EEG data were recorded. The adapted IGT we used allowed us to analyze the choice evaluation, response selection, and feedback evaluation stages of uncertain decision making within the same paradigm. In the choice evaluation stage, the advantageous decks evoked larger P3 amplitude in the left hemisphere, while the disadvantageous decks evoked larger P3 in the right hemisphere. In the response selection stage, the response of pass (the card was not turned over; the participants neither won nor lost money evoked larger negativity preceding the response compared to that of play (the card was turned over; the participant either won or lost money. In the feedback evaluation stage, feedback-related negativity was only sensitive to the valence (win/loss but not the magnitude (large/small of the outcome, and P3 was sensitive to both the valence and the magnitude of the outcome. These results were consistent with the notion that a positive somatic state was represented in the left hemisphere and a negative somatic state was represented in the right hemisphere. There were also anticipatory ERP effects that guided the participants’ responses and provided evidence for the somatic marker hypothesis with more precise timing.

  14. Neural correlates of uncertain decision making: ERP evidence from the Iowa Gambling Task.

    Science.gov (United States)

    Cui, Ji-Fang; Chen, Ying-He; Wang, Ya; Shum, David H K; Chan, Raymond C K

    2013-01-01

    In our daily life, it is very common to make decisions in uncertain situations. The Iowa Gambling Task (IGT) has been widely used in laboratory studies because of its good simulation of uncertainty in real life activities. The present study aimed to examine the neural correlates of uncertain decision making with the IGT. Twenty-six university students completed this study. An adapted IGT was administered to them, and the EEG data were recorded. The adapted IGT we used allowed us to analyze the choice evaluation, response selection, and feedback evaluation stages of uncertain decision making within the same paradigm. In the choice evaluation stage, the advantageous decks evoked larger P3 amplitude in the left hemisphere, while the disadvantageous decks evoked larger P3 in the right hemisphere. In the response selection stage, the response of "pass" (the card was not turned over; the participants neither won nor lost money) evoked larger negativity preceding the response compared to that of "play" (the card was turned over; the participant either won or lost money). In the feedback evaluation stage, feedback-related negativity (FRN) was only sensitive to the valence (win/loss) but not the magnitude (large/small) of the outcome, and P3 was sensitive to both the valence and the magnitude of the outcome. These results were consistent with the notion that a positive somatic state was represented in the left hemisphere and a negative somatic state was represented in the right hemisphere. There were also anticipatory ERP effects that guided the participants' responses and provided evidence for the somatic marker hypothesis with more precise timing.

  15. Performance-Driven Robust Identification and Control of Uncertain Dynamical Systems

    Energy Technology Data Exchange (ETDEWEB)

    Basar, Tamer

    2001-10-29

    The grant DEFG02-97ER13939 from the Department of Energy has supported our research program on robust identification and control of uncertain dynamical systems, initially for the three-year period June 15, 1997-June 14, 2000, which was then extended on a no-cost basis for another year until June 14, 2001. This final report provides an overview of our research conducted during this period, along with a complete list of publications supported by the Grant. Within the scope of this project, we have studied fundamental issues that arise in modeling, identification, filtering, control, stabilization, control-based model reduction, decomposition and aggregation, and optimization of uncertain systems. The mathematical framework we have worked in has allowed the system dynamics to be only partially known (with the uncertainties being of both parametric or structural nature), and further the dynamics to be perturbed by unknown dynamic disturbances. Our research over these four years has generated a substantial body of new knowledge, and has led to new major developments in theory, applications, and computational algorithms. These have all been documented in various journal articles and book chapters, and have been presented at leading conferences, as to be described. A brief description of the results we have obtained within the scope of this project can be found in Section 3. To set the stage for the material of that section, we first provide in the next section (Section 2) a brief description of the issues that arise in the control of uncertain systems, and introduce several criteria under which optimality will lead to robustness and stability. Section 4 contains a list of references cited in these two sections. A list of our publications supported by the DOE Grant (covering the period June 15, 1997-June 14, 2001) comprises Section 5 of the report.

  16. Using the threat probability task to assess anxiety and fear during uncertain and certain threat.

    Science.gov (United States)

    Bradford, Daniel E; Magruder, Katherine P; Korhumel, Rachel A; Curtin, John J

    2014-09-12

    Fear of certain threat and anxiety about uncertain threat are distinct emotions with unique behavioral, cognitive-attentional, and neuroanatomical components. Both anxiety and fear can be studied in the laboratory by measuring the potentiation of the startle reflex. The startle reflex is a defensive reflex that is potentiated when an organism is threatened and the need for defense is high. The startle reflex is assessed via electromyography (EMG) in the orbicularis oculi muscle elicited by brief, intense, bursts of acoustic white noise (i.e., "startle probes"). Startle potentiation is calculated as the increase in startle response magnitude during presentation of sets of visual threat cues that signal delivery of mild electric shock relative to sets of matched cues that signal the absence of shock (no-threat cues). In the Threat Probability Task, fear is measured via startle potentiation to high probability (100% cue-contingent shock; certain) threat cues whereas anxiety is measured via startle potentiation to low probability (20% cue-contingent shock; uncertain) threat cues. Measurement of startle potentiation during the Threat Probability Task provides an objective and easily implemented alternative to assessment of negative affect via self-report or other methods (e.g., neuroimaging) that may be inappropriate or impractical for some researchers. Startle potentiation has been studied rigorously in both animals (e.g., rodents, non-human primates) and humans which facilitates animal-to-human translational research. Startle potentiation during certain and uncertain threat provides an objective measure of negative affective and distinct emotional states (fear, anxiety) to use in research on psychopathology, substance use/abuse and broadly in affective science. As such, it has been used extensively by clinical scientists interested in psychopathology etiology and by affective scientists interested in individual differences in emotion.

  17. Remaining teeth, cardiovascular morbidity and death among adult Danes

    DEFF Research Database (Denmark)

    Heitmann, B L; Gamborg, M

    2008-01-01

    OBJECTIVE: To examine if number of remaining teeth was associated with development of cardiovascular morbidity and mortality over 5-12 years. METHODS: Prospective observational study among 1474 men and 1458 women born 1922, 1932, 1942 or 1952 from The Danish MONICA follow up study (MONItoring......, incidence of cardiovascular disease and coronary heart disease, during averagely 7.5 years of follow-up. Compared to those with most teeth remaining, the edentulous suffered >3-fold increased Hazard (HR) of developing stroke (HR=3.25; 95% CI: 1.48-7.14), whereas the risk of developing any cardiovascular...... disease was increased by 50% (HR=1.50; 95% CI: 1.02-2.19). Risk for coronary heart disease was increased by 31%, but was not significant, after the adjustment for education, age, smoking, diabetes, alcohol intake, systolic blood pressure and body mass index (HR= 1.31; 95% CI: 0.74-2.31). Associations were...

  18. Mandibular remains support taxonomic validity of Australopithecus sediba.

    Science.gov (United States)

    de Ruiter, Darryl J; DeWitt, Thomas J; Carlson, Keely B; Brophy, Juliet K; Schroeder, Lauren; Ackermann, Rebecca R; Churchill, Steven E; Berger, Lee R

    2013-04-12

    Since the announcement of the species Australopithecus sediba, questions have been raised over whether the Malapa fossils represent a valid taxon or whether inadequate allowance was made for intraspecific variation, in particular with reference to the temporally and geographically proximate species Au. africanus. The morphology of mandibular remains of Au. sediba, including newly recovered material discussed here, shows that it is not merely a late-surviving morph of Au. africanus. Rather-as is seen elsewhere in the cranium, dentition, and postcranial skeleton-these mandibular remains share similarities with other australopiths but can be differentiated from the hypodigm of Au. africanus in both size and shape as well as in their ontogenetic growth trajectory.

  19. Suicidal terrorist bombings in Israel--identification of human remains.

    Science.gov (United States)

    Kahana, T; Freund, M; Hiss, J

    1997-03-01

    Positive identification of human remains is one of the most important tasks in mass disaster investigations. Religious and jurisdictional demands in Israel, require the identification process to be completed in the shortest possible time. In the 18 suicidal terrorist bombings that took place in Israel between the years 1993-1996, 127 victims and 19 perpetrators were killed, and their severely fragmented bodies were identified within 24 h. The efficient completion of the identification endeavor was enabled by the implementation of a variety of techniques and the close collaboration in the investigation between the different emergency and forensic agencies. This paper presents the mass disaster identification policy and techniques currently used in Israel. The importance of an interdisciplinary approach for the identification of extremely fragmented human remains from mass disasters and the creation of a central data bank of fingerprints and genetic markers is emphasized.

  20. The impact of downsizing on remaining workers' sickness absence.

    Science.gov (United States)

    Østhus, Ståle; Mastekaasa, Arne

    2010-10-01

    It is generally assumed that organizational downsizing has considerable negative consequences, not only for workers that are laid off, but also for those who remain employed. The empirical evidence with regard to effects on sickness absence is, however, inconsistent. This study employs register data covering a major part of the total workforce in Norway over the period 2000-2003. The number of sickness absence episodes and the number of sickness absence days are analysed by means of Poisson regression. To control for both observed and unobserved stable individual characteristics, we use conditional (fixed effects) estimation. The analyses provide some weak indications that downsizing may lead to slightly less sickness absence, but the overall impression is that downsizing has few if any effects on the sickness absence of the remaining employees. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Mineral remains of early life on Earth? On Mars?

    Science.gov (United States)

    Iberall, Robbins E.; Iberall, A.S.

    1991-01-01

    The oldest sedimentary rocks on Earth, the 3.8-Ga Isua Iron-Formation in southwestern Greenland, are metamorphosed past the point where organic-walled fossils would remain. Acid residues and thin sections of these rocks reveal ferric microstructures that have filamentous, hollow rod, and spherical shapes not characteristic of crystalline minerals. Instead, they resemble ferric-coated remains of bacteria. Because there are no earlier sedimentary rocks to study on Earth, it may be necessary to expand the search elsewhere in the solar system for clues to any biotic precursors or other types of early life. A study of morphologies of iron oxide minerals collected in the southern highlands during a Mars sample return mission may therefore help to fill in important gaps in the history of Earth's earliest biosphere. -from Authors

  2. Control uncertain Genesio-Tesi chaotic system: Adaptive sliding mode approach

    Energy Technology Data Exchange (ETDEWEB)

    Dadras, Sara [Automation and Instruments Lab, Electrical Engineering Department, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)], E-mail: s_dadras@modares.ac.ir; Momeni, Hamid Reza [Automation and Instruments Lab, Electrical Engineering Department, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)], E-mail: momeni_h@modares.ac.ir

    2009-12-15

    An adaptive sliding mode control (ASMC) technique is introduced in this paper for a chaotic dynamical system (Genesio-Tesi system). Using the sliding mode control technique, a sliding surface is determined and the control law is established. An adaptive sliding mode control law is derived to make the states of the Genesio-Tesi system asymptotically track and regulate the desired state. The designed control scheme can control the uncertain chaotic behaviors to a desired state without oscillating very fast and guarantee the property of asymptotical stability. An illustrative simulation result is given to demonstrate the effectiveness of the proposed adaptive sliding mode control design.

  3. Adaptive Fuzzy Control for Uncertain Fractional-Order Financial Chaotic Systems Subjected to Input Saturation.

    Science.gov (United States)

    Wang, Chenhui

    2016-01-01

    In this paper, control of uncertain fractional-order financial chaotic system with input saturation and external disturbance is investigated. The unknown part of the input saturation as well as the system's unknown nonlinear function is approximated by a fuzzy logic system. To handle the fuzzy approximation error and the estimation error of the unknown upper bound of the external disturbance, fractional-order adaptation laws are constructed. Based on fractional Lyapunov stability theorem, an adaptive fuzzy controller is designed, and the asymptotical stability can be guaranteed. Finally, simulation studies are given to indicate the effectiveness of the proposed method.

  4. Adaptive Fuzzy Control for Uncertain Fractional-Order Financial Chaotic Systems Subjected to Input Saturation.

    Directory of Open Access Journals (Sweden)

    Chenhui Wang

    Full Text Available In this paper, control of uncertain fractional-order financial chaotic system with input saturation and external disturbance is investigated. The unknown part of the input saturation as well as the system's unknown nonlinear function is approximated by a fuzzy logic system. To handle the fuzzy approximation error and the estimation error of the unknown upper bound of the external disturbance, fractional-order adaptation laws are constructed. Based on fractional Lyapunov stability theorem, an adaptive fuzzy controller is designed, and the asymptotical stability can be guaranteed. Finally, simulation studies are given to indicate the effectiveness of the proposed method.

  5. Robust Synchronization Controller Design for a Class of Uncertain Fractional Order Chaotic Systems

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2016-01-01

    Full Text Available Synchronization problem for a class of uncertain fractional order chaotic systems is studied. Some fundamental lemmas are given to show the boundedness of a complicated infinite series which is produced by differentiating a quadratic Lyapunov function with fractional order. By using the fractional order extension of the Lyapunov stability criterion and the proposed lemma, stability of the closed-loop system is analyzed, and two sufficient conditions, which can enable the synchronization error to converge to zero asymptotically, are driven. Finally, an illustrative example is presented to confirm the proposed theoretical results.

  6. The sensorimotor system minimizes prediction error for object lifting when the object's weight is uncertain.

    Science.gov (United States)

    Brooks, Jack; Thaler, Anne

    2017-08-01

    A reliable mechanism to predict the heaviness of an object is important for manipulating an object under environmental uncertainty. Recently, Cashaback et al. (Cashaback JGA, McGregor HR, Pun HCH, Buckingham G, Gribble PL. J Neurophysiol 117: 260-274, 2017) showed that for object lifting the sensorimotor system uses a strategy that minimizes prediction error when the object's weight is uncertain. Previous research demonstrates that visually guided reaching is similarly optimized. Although this suggests a unified strategy of the sensorimotor system for object manipulation, the selected strategy appears to be task dependent and subject to change in response to the degree of environmental uncertainty. Copyright © 2017 the American Physiological Society.

  7. Dynamics of Uncertain Discrete-Time Neural Network with Delay and Impulses

    Directory of Open Access Journals (Sweden)

    Xuehui Mei

    2015-01-01

    Full Text Available The stability of discrete-time impulsive delay neural networks with and without uncertainty is investigated. First, by using Razumikhin-type theorem, a new less conservative condition for the exponential stability of discrete-time neural network with delay and impulse is proposed. Moreover, some new sufficient conditions are derived to guarantee the stability of uncertain discrete-time neural network with delay and impulse by using Lyapunov function and linear matrix inequality (LMI. Finally, several examples with numerical simulation are presented to demonstrate the effectiveness of the obtained results.

  8. State-feedback stabilisation for stochastic non-holonomic mobile robots with uncertain visual servoing parameters

    Science.gov (United States)

    Zhang, Dongkai; Wang, Chaoli; Wei, Guoliang; Zhang, Hengjun; Chen, Hua

    2014-07-01

    The stabilising problem of stochastic non-holonomic mobile robots with uncertain parameters based on visual servoing is addressed in this paper. The model of non-holonomic mobile robots based on visual servoing is extended to the stochastic case, where their forward velocity and angular velocity are both subject to some stochastic disturbances. Based on backstepping technique, state-feedback stabilising controllers are designed for stochastic non-holonomic mobile robots. A switching control strategy for the original system is presented. The proposed controllers guarantee that the closed-loop system is asymptotically stabilised at the zero equilibrium point in probability.

  9. Terminal Sliding Mode Control with Adaptive Law for Uncertain Nonlinear System

    Directory of Open Access Journals (Sweden)

    Zhanshan Zhao

    2015-01-01

    Full Text Available A novel nonsingular terminal sliding mode controller is proposed for a second-order system with unmodeled dynamics uncertainties and external disturbances. We need not achieve the knowledge for boundaries of uncertainties and external disturbances in advance. The adaptive control gains are obtained to estimate the uncertain parameters and external disturbances which are unknown but bounded. The closed loop system stability is ensured with robustness and adaptation by the Lyapunov stability theorem in finite time. An illustrative example of second-order nonlinear system with unmodeled dynamics and external disturbances is given to demonstrate the effectiveness of the presented scheme.

  10. Finite time control of uncertain networked switched linear systems with quantizations

    Science.gov (United States)

    Chen, Xiaoling; Zhou, Guopeng; Tian, Fengxia; Liu, Hao

    2017-01-01

    This paper is concerned with the finite-time control problem for uncertain networked switched linear systems with both state and control input quantizations. By employing average well dwell time (ADT) and Lyapunov-like function method, a feedback controller is designed to guarantee that the dynamic augment closed-loop system is finite-time boundedness. Then based on this, some sufficient conditions which ensure the finite-time boundedness of networked switched systems are derived in terms of linear matrix inequalities. Finally, a numerical example is given to illustrate the effectiveness of the proposed design approach.

  11. A Sense of Security: Carpentry Apprentices Handling Uncertain and Dangerous Work Tasks

    DEFF Research Database (Denmark)

    Grytnes, Regine

    2018-01-01

    This article explores how carpentry apprentices learn to handle uncertain and potentially dangerous situations in the working environment at construction sites. The analysis focuses on how these situations are negotiated at the workplaces in relation to bodily sensations of pain, relations...... with their co-workers and the importance placed on ‘getting the work done’. It shows that instead of working to eliminate potentially dangerous situations through the use of precautionary measures such as lifting equipment or personal protection gear, the apprentices learn to understand risk and uncertainties...

  12. A Copositive Approach for Two-Stage Adjustable Robust Optimization with Uncertain Right-Hand Sides

    OpenAIRE

    Xu, Guanglin; Burer, Samuel

    2016-01-01

    We study two-stage adjustable robust linear programming in which the right-hand sides are uncertain and belong to a convex, compact uncertainty set. This problem is NP-hard, and the affine policy is a popular, tractable approximation. We prove that under standard and simple conditions, the two-stage problem can be reformulated as a copositive optimization problem, which in turn leads to a class of tractable, semidefinite-based approximations that are at least as strong as the affine policy. W...

  13. Synchronization of fractional-order uncertain chaotic systems with input nonlinearity

    Science.gov (United States)

    Noghredani, Naeimadeen; Balochian, Saeed

    2015-05-01

    In this paper, sliding mode control has been designed for synchronization of fractional order uncertain chaotic systems with input nonlinearity. First, sliding mode control law has been taken from chaotic state error system which is asymptotically stable. Second, the shown sliding mode control ensures that fractional-order error system is asymptotically stable in the presence of uncertainty and nonlinear input. Simulation results using MATLAB software show that the designed controller is able to synchronize fractional-order chaotic systems in the presence of the mentioned factors.

  14. Adaptive synchronization of drive-response fractional-order complex dynamical networks with uncertain parameters

    Science.gov (United States)

    Yang, Li-xin; Jiang, Jun

    2014-05-01

    This paper investigates the adaptive synchronization in the drive-response fractional-order dynamical networks with uncertain parameters. By means of both the stability theory of fractional-order differential system and the adaptive control technique, a novel adaptive synchronization controller is developed with a more general and simpler analytical expression, which does not contain the parameters of the complex network, and effective adaptive laws of parameters. Furthermore, the very strong and conservative uniformly Lipschitz condition on the node dynamics of complex network is released. To demonstrate the validity of the proposed method, the examples for the synchronization of systems with the chaotic and hyper-chaotic node dynamics are presented.

  15. Robust H∞ Filtering for Uncertain Neutral Stochastic Systems with Markovian Jumping Parameters and Time Delay

    Directory of Open Access Journals (Sweden)

    Yajun Li

    2015-01-01

    Full Text Available This paper deals with the robust H∞ filter design problem for a class of uncertain neutral stochastic systems with Markovian jumping parameters and time delay. Based on the Lyapunov-Krasovskii theory and generalized Finsler Lemma, a delay-dependent stability condition is proposed to ensure not only that the filter error system is robustly stochastically stable but also that a prescribed H∞ performance level is satisfied for all admissible uncertainties. All obtained results are expressed in terms of linear matrix inequalities which can be easily solved by MATLAB LMI toolbox. Numerical examples are given to show that the results obtained are both less conservative and less complicated in computation.

  16. Decentralized H∞ Control for Uncertain Interconnected Systems of Neutral Type via Dynamic Output Feedback

    Directory of Open Access Journals (Sweden)

    Heli Hu

    2014-01-01

    Full Text Available The design of the dynamic output feedback H∞ control for uncertain interconnected systems of neutral type is investigated. In the framework of Lyapunov stability theory, a mathematical technique dealing with the nonlinearity on certain matrix variables is developed to obtain the solvability conditions for the anticipated controller. Based on the corresponding LMIs, the anticipated gains for dynamic output feedback can be achieved by solving some algebraic equations. Also, the norm of the transfer function from the disturbance input to the controlled output is less than the given index. A numerical example and the simulation results are given to show the effectiveness of the proposed method.

  17. Planning the Minimum Time and Optimal Survey Trajectory for Autonomous Underwater Vehicles in Uncertain Current

    Directory of Open Access Journals (Sweden)

    Michael A. Hurni

    2015-12-01

    Full Text Available The authors develop an approach to a “best” time path for Autonomous Underwater Vehicles conducting oceanographic measurements under uncertain current flows. The numerical optimization tool DIDO is used to compute hybrid minimum time and optimal survey paths for a sample of currents between ebb and flow. A simulated meta-experiment is performed where the vehicle traverses the resulting paths under different current strengths per run. The fastest elapsed time emerges from a payoff table. A multi-objective function is then used to weigh the time to complete a mission versus measurement inaccuracy due to deviation from the desired survey path.

  18. Passivity of memristor-based BAM neural networks with different memductance and uncertain delays.

    Science.gov (United States)

    Anbuvithya, R; Mathiyalagan, K; Sakthivel, R; Prakash, P

    2016-08-01

    This paper addresses the passivity problem for a class of memristor-based bidirectional associate memory (BAM) neural networks with uncertain time-varying delays. In particular, the proposed memristive BAM neural networks is formulated with two different types of memductance functions. By constructing proper Lyapunov-Krasovskii functional and using differential inclusions theory, a new set of sufficient condition is obtained in terms of linear matrix inequalities which guarantee the passivity criteria for the considered neural networks. Finally, two numerical examples are given to illustrate the effectiveness of the proposed theoretical results.

  19. Quantification of uncertain outcomes from site characterization: Insights from the ESF-AS

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, W.J.; Parrish, D.K. [RE/SPEC, Inc., Rapid City, SD (United States); Beccue, P.C. [Applied Decision Analysis, Inc., Menlo Park, CA (United States)

    1992-01-01

    As part of the Exploratory Studies Facility Alternatives Study (ESF-AS) the uncertain outcomes from site characterization were quantified using a probabilistic tree known as ``Nature`s Tree.`` Nature`s Tree distinguished the true characteristics of the Yucca Mountain site from the perceived characteristics deduced from testing. Bayesian probabilistic calculations converted probabilities in Nature`s Tree to the probabilistic estimates required for the comparative analysis of Exploratory Studies Facility-repository options. Experts on characterization testing explicitly addressed several site characterization issues that are considered implicitly in many site characterization programs.

  20. Neanderthal infant and adult infracranial remains from Marillac (Charente, France).

    Science.gov (United States)

    Dolores Garralda, María; Maureille, Bruno; Vandermeersch, Bernard

    2014-09-01

    At the site of Marillac, near the Ligonne River in Marillac-le-Franc (Charente, France), a remarkable stratigraphic sequence has yielded a wealth of archaeological information, palaeoenvironmental data, as well as faunal and human remains. Marillac must have been a sinkhole used by Neanderthal groups as a hunting camp during MIS 4 (TL date 57,600 ± 4,600BP), where Quina Mousterian lithics and fragmented bones of reindeer predominate. This article describes three infracranial skeleton fragments. Two of them are from adults and consist of the incomplete shafts of a right radius (Marillac 24) and a left fibula (Marillac 26). The third fragment is the diaphysis of the right femur of an immature individual (Marillac 25), the size and shape of which resembles those from Teshik-Tash and could be assigned to a child of a similar age. The three fossils have been compared with the remains of other Neanderthals or anatomically Modern Humans (AMH). Furthermore, the comparison of the infantile femora, Marillac 25 and Teshik-Tash, with the remains of several European children from the early Middle Ages clearly demonstrates the robustness and rounded shape of both Neanderthal diaphyses. Evidence of peri-mortem manipulations have been identified on all three bones, with spiral fractures, percussion pits and, in the case of the radius and femur, unquestionable cutmarks made with flint implements, probably during defleshing. Traces of periostosis appear on the fibula fragment and on the immature femoral diaphysis, although their aetiology remains unknown. Copyright © 2014 Wiley Periodicals, Inc.

  1. Are there stress resistant and susceptible myocardia?

    Science.gov (United States)

    Knight, V A

    1988-11-01

    The satisfactory analysis of the Na/K ATPase, its pumping component and the mechanism of action of the inhibitor digitalis remains elusive; yet the controversial inotropic effect of digitalis in the clinical setting has been known for over a century. There are also conflicting reports of the effect of urea and uremia on the cardiovascular system, and the evidence as it exists, suggests that urea may have two effects on the intact heart, by virtue of its extent of action on hydrogen bonding of water molecules, determined by which type of muscle constitutes the myocardium. If different types of myocardium do exist, they could well respond differently to inotropic agents. Evidence suggests that two types of myocardia, relatively stress resistant or susceptible may exist, analagous to known skeletal muscle differences.

  2. Osteometric sex determination of burned human skeletal remains.

    Science.gov (United States)

    Gonçalves, D; Thompson, T J U; Cunha, E

    2013-10-01

    Sex determination of human burned skeletal remains is extremely hard to achieve because of heat-related fragmentation, warping and dimensional changes. In particular, the latter is impeditive of osteometric analyses that are based on references developed on unburned bones. New osteometric references were thus obtained which allow for more reliable sex determinations. The calcined remains of cremated Portuguese individuals were examined and specific standard measurements of the humerus, femur, talus and calcaneus were recorded. This allowed for the compilation of new sex discriminating osteometric references which were then tested on independent samples with good results. Both the use of simple section points and of logistic regression equations provided successful sex classification scores. These references may now be used for the sex determination of burned skeletons. Its reliability is highest for contemporary Portuguese remains but nonetheless these results have important repercussion for forensic research. More conservative use of these references may also prove valuable for other populations as well as for archaeological research. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  3. Field contamination of skeletonized human remains with exogenous DNA.

    Science.gov (United States)

    Edson, Suni M; Christensen, Alexander F

    2013-01-01

    The Armed Forces DNA Identification Laboratory reports the mitochondrial DNA (mtDNA) sequences of over 800 skeletal samples a year for the Joint POW/MIA Accounting Command-Central Identification Laboratory. These sequences are generated from degraded skeletal remains that are presumed to belong to U.S. service members missing from past military conflicts. In the laboratory, it is possible to control for contamination of remains; however, in the field, it can be difficult to prevent modern DNA from being transferred to skeletal elements and being carried forward through the analysis process. Four such cases are described here along with the controls in place in the laboratory to eliminate the possibility of the exogenous DNA being reported as authentic. In each case, the controls implemented by the laboratories prevented the false reporting of contaminant exogenous DNA from remains that were either faunal or human, but lacked endogenous DNA. © 2012 American Academy of Forensic Sciences Published 2012. This article is a U.S. Government work and is in the public domain in the U.S.A.

  4. Postmortem Scavenging of Human Remains by Domestic Cats

    Directory of Open Access Journals (Sweden)

    Ananya Suntirukpong, M.D.

    2017-11-01

    Full Text Available Objective: Crime scene investigators, forensic medicine doctors and pathologists, and forensic anthropologists frequently encounter postmortem scavenging of human remains by household pets. Case presentation: The authors present a case report of a partially skeletonized adult male found dead after more than three months in his apartment in Thailand. The body was in an advanced stage of decomposition with nearly complete skeletonization of the head, neck, hands, and feet. The presence of maggots and necrophagous (flesh eating beetles on the body confirmed that insects had consumed much of the soft tissues. Examination of the hand and foot bones revealed canine tooth puncture marks. Evidence of chewing indicated that one or more of the decedent’s three house cats had fed on the body after death. Recognizing and identifying carnivore and rodent activity on the soft flesh and bones of human remains is important in interpreting and reconstructing postmortem damage. Thorough analysis may help explain why skeletal elements are missing, damaged, or out of anatomical position. Conclusion: This report presents a multi-disciplinary approach combining forensic anthropology and forensic medicine in examining and interpreting human remains.

  5. Choosing and remaining in nursing: Iranian male nurses' perspectives.

    Science.gov (United States)

    Zamanzadeh, Vahid; Azadi, Arman; Valizadeh, Leila; Keogh, Brian; Monadi, Morteza; Negarandeh, Reza

    2013-10-01

    Iranian male nurses' career-choosing practices have not been well investigated. The aim of this study was to explore the reasons why Iranian male nurses choose nursing as a career. In addition it sought to understand the reasons why they remain in nursing. An exploratory descriptive design, employing a qualitative approach was used. Eighteen semi-structured interviews were conducted and analyzed using content analysis. The analysis culminated in the development of three themes which described the participants' motivations for choosing nursing as a career as well as the factors that influenced their decisions to remain in nursing following qualification. Practical motivations such as job security were important factors in choosing nursing. The most common reason for remaining in nursing was desire to care for others, for God's sake. Factors that influenced their decision to leave mainly centered on the public view to nursing as a feminine discipline. However, the nurses in this study believed that nursing was a profession appropriate for both men and women because of gendered nursing care and preferences of patient in Iran.

  6. A landslide susceptibility map of Africa

    Science.gov (United States)

    Broeckx, Jente; Vanmaercke, Matthias; Duchateau, Rica; Poesen, Jean

    2017-04-01

    Studies on landslide risks and fatalities indicate that landslides are a global threat to humans, infrastructure and the environment, certainly in Africa. Nonetheless our understanding of the spatial patterns of landslides and rockfalls on this continent is very limited. Also in global landslide susceptibility maps, Africa is mostly underrepresented in the inventories used to construct these maps. As a result, predicted landslide susceptibilities remain subject to very large uncertainties. This research aims to produce a first continent-wide landslide susceptibility map for Africa, calibrated with a well-distributed landslide dataset. As a first step, we compiled all available landslide inventories for Africa. This data was supplemented by additional landslide mapping with Google Earth in underrepresented regions. This way, we compiled 60 landslide inventories from the literature (ca. 11000 landslides) and an additional 6500 landslides through mapping in Google Earth (including 1500 rockfalls). Various environmental variables such as slope, lithology, soil characteristics, land use, precipitation and seismic activity, were investigated for their significance in explaining the observed spatial patterns of landslides. To account for potential mapping biases in our dataset, we used Monte Carlo simulations that selected different subsets of mapped landslides, tested the significance of the considered environmental variables and evaluated the performance of the fitted multiple logistic regression model against another subset of mapped landslides. Based on these analyses, we constructed two landslide susceptibility maps for Africa: one for all landslide types and one excluding rockfalls. In both maps, topography, lithology and seismic activity were the most significant variables. The latter factor may be surprising, given the overall limited degree of seismicity in Africa. However, its significance indicates that frequent seismic events may serve as in important

  7. Robust Nonfragile Controllers Design for Fractional Order Large-Scale Uncertain Systems with a Commensurate Order 1<α<2

    Directory of Open Access Journals (Sweden)

    Jianyu Lin

    2015-01-01

    uncertain systems with a commensurate order 1<α<2 under controller gain uncertainties. The uncertainties are of norm-bounded type. Based on the stability criterion of fractional order system, sufficient conditions on the decentralized stabilization of fractional order large-scale uncertain systems in both cases of additive and multiplicative gain perturbations are established by using the complex Lyapunov inequality. Moreover, the decentralized nonfragile controllers are designed. Finally, some numerical examples are given to validate the proposed method.

  8. Energy planning under uncertain decision-making environment: An evidential reasoning approach to prioritize renewable energy sources

    OpenAIRE

    Hamza Sellak; Brahim Ouhbi; Bouchra Frikh

    2017-01-01

    Nowadays, making strategic decisions in a sensitive sector such as energy planning that usually requires allocating huge funds, time, and resources is a difficult task. For instance, prioritizing a set of Renewable Energy Sources (RES) is a complex multi-dimensional task that typically involves a range of conflicting criteria featuring different forms of evaluation data in an uncertain decision-making environment. This process is aligned with several sources that can be uncertain,...

  9. Delay-Dependent Stability Criteria of Uncertain Periodic Switched Recurrent Neural Networks with Time-Varying Delays

    Directory of Open Access Journals (Sweden)

    Xing Yin

    2011-01-01

    uncertain periodic switched recurrent neural networks with time-varying delays. When uncertain discrete-time recurrent neural network is a periodic system, it is expressed as switched neural network for the finite switching state. Based on the switched quadratic Lyapunov functional approach (SQLF and free-weighting matrix approach (FWM, some linear matrix inequality criteria are found to guarantee the delay-dependent asymptotical stability of these systems. Two examples illustrate the exactness of the proposed criteria.

  10. Topological susceptibility from the overlap

    DEFF Research Database (Denmark)

    Del Debbio, Luigi; Pica, Claudio

    2003-01-01

    The chiral symmetry at finite lattice spacing of Ginsparg-Wilson fermionic actions constrains the renormalization of the lattice operators; in particular, the topological susceptibility does not require any renormalization, when using a fermionic estimator to define the topological charge. Theref...

  11. Clinical significance of coryneform Gram-positive rods from blood identified by MALDI-TOF mass spectrometry and their susceptibility profiles - a retrospective chart review.

    Science.gov (United States)

    Mushtaq, Ammara; Chen, Derrick J; Strand, Gregory J; Dylla, Brenda L; Cole, Nicolynn C; Mandrekar, Jayawant; Patel, Robin

    2016-07-01

    With the advent of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), most Gram-positive rods (GPRs) are readily identified; however, their clinical relevance in blood cultures remains unclear. Herein, we assessed the clinical significance of GPRs isolated from blood and identified in the era of MALDI-TOF MS. A retrospective chart review of patients presenting to the Mayo Clinic, Rochester, MN, from January 1, 2013, to October 13, 2015, was performed. Any episode of a positive blood culture for a GPR was included. We assessed the number of bottles positive for a given isolate, time to positivity of blood cultures, patient age, medical history, interpretation of culture results by the healthcare team and whether infectious diseases consultation was obtained. We also evaluated the susceptibility profiles of a larger collection of GPRs tested in the clinical microbiology laboratory of the Mayo Clinic, Rochester, MN from January 1, 2013, to October 31, 2015. There were a total of 246 GPRs isolated from the blood of 181 patients during the study period. 56% (n = 101) were deemed contaminants by the healthcare team and were not treated; 33% (n = 59) were clinically determined to represent true bacteremia and were treated; and 8% (n = 14) were considered of uncertain significance, with patients prescribed treatment regardless. Patient characteristics associated with an isolate being treated on univariate analysis included younger age (P = 0.02), identification to the species level (P = 0.02), higher number of positive blood culture sets (P blood culture sets (P = 0.0005) and lower time to positivity (P = 0.03) were associated with an isolate being treated. 100, 83, 48 and 34% of GPRs were susceptible to vancomycin, meropenem, penicillin and ceftriaxone, respectively. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Iron mapping using the temperature dependency of the magnetic susceptibility.

    Science.gov (United States)

    Birkl, Christoph; Langkammer, Christian; Krenn, Heinz; Goessler, Walter; Ernst, Christina; Haybaeck, Johannes; Stollberger, Rudolf; Fazekas, Franz; Ropele, Stefan

    2015-03-01

    The assessment of iron content in brain white matter (WM) is of high importance for studying neurodegenerative diseases. While R2 * mapping and quantitative susceptibility mapping is suitable for iron mapping in gray matter, iron mapping in WM still remains an unsolved problem. We propose a new approach for iron mapping, independent of diamagnetic contributions of myelin by assessing the temperature dependency of the paramagnetic susceptibility. We used unfixed human brain slices for relaxometry and calculated R2 ' as a measure for microscopic susceptibility variations at several temperatures (4°C-37°C) at 3 Tesla. The temperature coefficient of R2 ' (TcR2p) was calculated by linear regression and related to the iron concentration found by subsequent superconducting quantum interference device (SQUID) magnetometry and by inductively coupled plasma mass spectrometry. In line with SQUID measurements, R2 ' mapping showed a linear temperature dependency of the bulk susceptibility with the highest slope in gray matter. Even in WM, TcR2p yielded a high linear correlation with the absolute iron concentration. According to Curie's law, only paramagnetic matter exhibits a temperature dependency while the diamagnetism shows no effect. We have demonstrated that the temperature coefficient (TcR2p) can be used as a measure of the paramagnetic susceptibility despite of an unknown diamagnetic background. © 2014 Wiley Periodicals, Inc.

  13. Expert opinion on landslide susceptibility elicted by probabilistic inversion from scenario rankings

    Science.gov (United States)

    Lee, Katy; Dashwood, Claire; Lark, Murray

    2016-04-01

    For many natural hazards the opinion of experts, with experience in assessing susceptibility under different circumstances, is a valuable source of information on which to base risk assessments. This is particularly important where incomplete process understanding, and limited data, limit the scope to predict susceptibility by mechanistic or statistical modelling. The expert has a tacit model of a system, based on their understanding of processes and their field experience. This model may vary in quality, depending on the experience of the expert. There is considerable interest in how one may elicit expert understanding by a process which is transparent and robust, to provide a basis for decision support. One approach is to provide experts with a set of scenarios, and then to ask them to rank small overlapping subsets of these with respect to susceptibility. Methods of probabilistic inversion have been used to compute susceptibility scores for each scenario, implicit in the expert ranking. It is also possible to model these scores as functions of measurable properties of the scenarios. This approach has been used to assess susceptibility of animal populations to invasive diseases, to assess risk to vulnerable marine environments and to assess the risk in hypothetical novel technologies for food production. We will present the results of a study in which a group of geologists with varying degrees of expertise in assessing landslide hazards were asked to rank sets of hypothetical simplified scenarios with respect to land slide susceptibility. We examine the consistency of their rankings and the importance of different properties of the scenarios in the tacit susceptibility model that their rankings implied. Our results suggest that this is a promising approach to the problem of how experts can communicate their tacit model of uncertain systems to those who want to make use of their expertise.

  14. Dynamical Scheduling and Robust Control in Uncertain Environments with Petri Nets for DESs

    Directory of Open Access Journals (Sweden)

    Dimitri Lefebvre

    2017-10-01

    Full Text Available This paper is about the incremental computation of control sequences for discrete event systems in uncertain environments where uncontrollable events may occur. Timed Petri nets are used for this purpose. The aim is to drive the marking of the net from an initial value to a reference one, in minimal or near-minimal time, by avoiding forbidden markings, deadlocks, and dead branches. The approach is similar to model predictive control with a finite set of control actions. At each step only a small area of the reachability graph is explored: this leads to a reasonable computational complexity. The robustness of the resulting trajectory is also evaluated according to a risk probability. A sufficient condition is provided to compute robust trajectories. The proposed results are applicable to a large class of discrete event systems, in particular in the domains of flexible manufacturing. However, they are also applicable to other domains as communication, computer science, transportation, and traffic as long as the considered systems admit Petri Nets (PNs models. They are suitable for dynamical deadlock-free scheduling and reconfiguration problems in uncertain environments.

  15. Adaptive Neural Output Feedback Control for Uncertain Robot Manipulators with Input Saturation

    Directory of Open Access Journals (Sweden)

    Rong Mei

    2017-01-01

    Full Text Available This paper presents an adaptive neural output feedback control scheme for uncertain robot manipulators with input saturation using the radial basis function neural network (RBFNN and disturbance observer. First, the RBFNN is used to approximate the system uncertainty, and the unknown approximation error of the RBFNN and the time-varying unknown external disturbance of robot manipulators are integrated as a compounded disturbance. Then, the state observer and the disturbance observer are proposed to estimate the unmeasured system state and the unknown compounded disturbance based on RBFNN. At the same time, the adaptation technique is employed to tackle the control input saturation problem. Utilizing the estimate outputs of the RBFNN, the state observer, and the disturbance observer, the adaptive neural output feedback control scheme is developed for robot manipulators using the backstepping technique. The convergence of all closed-loop signals is rigorously proved via Lyapunov analysis and the asymptotically convergent tracking error is obtained under the integrated effect of the system uncertainty, the unmeasured system state, the unknown external disturbance, and the input saturation. Finally, numerical simulation results are presented to illustrate the effectiveness of the proposed adaptive neural output feedback control scheme for uncertain robot manipulators.

  16. Cooperative Control of Heterogeneous Uncertain Dynamical Networks: An Adaptive Explicit Synchronization Framework.

    Science.gov (United States)

    Wang, Bohui; Wang, Jingcheng; Zhang, Langwen; Zhang, Bin; Li, Xiaocheng

    2017-06-01

    This paper proposes an adaptive explicit synchronization framework to address the cooperative control for heterogeneous uncertain dynamical networks under switching communication topologies. The main contribution is to develop an adaptive explicit synchronization algorithm, in which the synchronization state can be completely tracked by each agent in real time rather than only be measured after the synchronization process of all agents is over. By introducing appropriate assumptions, a class of adaptive explicit synchronization protocols is designed by using a combination of the virtual leader's states, the neighboring agents' relative information, distributed feedback gain, and distributed average weighted parameters. It is proved in the sense of Lyapunov that, if the dwell time is larger than a positive threshold, the cooperative control problem for the closed-loop heterogeneous uncertain dynamical networks under switching of strongly-connected communication topologies can be solved by the proposed adaptive explicit synchronization algorithm. Furthermore, by assuming that the topology is frequently strongly-connected, it shows that intermittent adaptive explicit synchronization can be achieved with well-designed control parameters. Two examples are presented to demonstrate the effectiveness of the proposed theory.

  17. Dynamic IQC-Based Control of Uncertain LFT Systems With Time-Varying State Delay.

    Science.gov (United States)

    Yuan, Chengzhi; Wu, Fen

    2016-12-01

    This paper presents a new exact-memory delay control scheme for a class of uncertain systems with time-varying state delay under the integral quadratic constraint (IQC) framework. The uncertain system is described as a linear fractional transformation model including a state-delayed linear time-invariant (LTI) system and time-varying structured uncertainties. The proposed exact-memory delay controller consists of a linear state-feedback control law and an additional term that captures the delay behavior of the plant. We first explore the delay stability and the L2 -gain performance using dynamic IQCs incorporated with quadratic Lyapunov functions. Then, the design of exact-memory controllers that guarantee desired L2 -gain performance is examined. The resulting delay control synthesis conditions are formulated in terms of linear matrix inequalities, which are convex on all design variables including the scaling matrices associated with the IQC multipliers. The IQC-based exact-memory control scheme provides a novel approach for delay control designs via convex optimization, and advances existing control methods in two important ways: 1) better controlled performance and 2) simplified design procedure with less computational cost. The effectiveness and advantages of the proposed approach have been demonstrated through numerical studies.

  18. A multitask sliding mode control for mismatched uncertain large-scale systems

    Science.gov (United States)

    Tsai, Yao-Wen; Van Huynh, Van

    2015-09-01

    A new sliding mode control (SMC) approach, output variables only, single phase only and chattering phenomenon free, is presented for a class of mismatched uncertain large-scale systems. For a new multitask SMC, it is not required that the system states are available. Moreover, the sliding function in this study just depends on output variables. Using an exponential type sliding surface, the system states are always in the sliding mode at the beginning time t = 0. Using a newly appropriate linear matrix inequality stability conditions by the Lyapunov method are derived such that each subsystem in the new sliding mode is completely invariant to matched uncertainties. As a result, robustness of the mismatched uncertain large-scale systems can be assured throughout an entire response of the system starting from the initial time t = 0. In every subsystem, a scheme of decentralised control using only output states is proposed. In addition, a continuous controller is finally designed for chattering removal. Finally, a numerical example is used to demonstrate the efficacy of the proposed method.

  19. Constrained control of uncertain, time-varying, discrete-time systems an interpolation-based approach

    CERN Document Server

    Nguyen, Hoai-Nam

    2014-01-01

    A comprehensive development of interpolating control, this monograph demonstrates the reduced computational complexity of a ground-breaking technique compared with the established model predictive control. The text deals with the regulation problem for linear, time-invariant, discrete-time uncertain dynamical systems having polyhedral state and control constraints, with and without disturbances, and under state or output feedback. For output feedback a non-minimal state-space representation is used with old inputs and outputs as state variables. Constrained Control of Uncertain, Time-Varying, Discrete-time Systems details interpolating control in both its implicit and explicit forms. In the former at most two linear-programming or one quadratic-programming problem are solved on-line at each sampling instant to yield the value of the control variable. In the latter the control law is shown to be piecewise affine in the state, and so the state space is partitioned into polyhedral cells so that at each sampling ...

  20. Practical Stabilization of Uncertain Nonholonomic Mobile Robots Based on Visual Servoing Model with Uncalibrated Camera Parameters

    Directory of Open Access Journals (Sweden)

    Hua Chen

    2013-01-01

    Full Text Available The practical stabilization problem is addressed for a class of uncertain nonholonomic mobile robots with uncalibrated visual parameters. Based on the visual servoing kinematic model, a new switching controller is presented in the presence of parametric uncertainties associated with the camera system. In comparison with existing methods, the new design method is directly used to control the original system without any state or input transformation, which is effective to avoid singularity. Under the proposed control law, it is rigorously proved that all the states of closed-loop system can be stabilized to a prescribed arbitrarily small neighborhood of the zero equilibrium point. Furthermore, this switching control technique can be applied to solve the practical stabilization problem of a kind of mobile robots with uncertain parameters (and angle measurement disturbance which appeared in some literatures such as Morin et al. (1998, Hespanha et al. (1999, Jiang (2000, and Hong et al. (2005. Finally, the simulation results show the effectiveness of the proposed controller design approach.

  1. Risk assessment of salt contamination of groundwater under uncertain aquifer properties

    KAUST Repository

    Litvinenko, Alexander

    2017-10-01

    One of the central topics in hydrogeology and environmental science is the investigation of salinity-driven groundwater flow in heterogeneous porous media. Our goals are to model and to predict pollution of water resources. We simulate a density driven groundwater flow with uncertain porosity and permeability. This strongly non-linear model describes the unstable transport of salt water with building ‘fingers’-shaped patterns. The computation requires a very fine unstructured mesh and, therefore, high computational resources. We run the highly-parallel multigrid solver, based on ug4, on supercomputer Shaheen II. A MPI-based parallelization is done in the geometrical as well as in the stochastic spaces. Every scenario is computed on 32 cores and requires a mesh with ~8M grid points and 1500 or more time steps. 200 scenarios are computed concurrently. The total number of cores in parallel computation is 200x32=6400. The main goal of this work is to estimate propagation of uncertainties through the model, to investigate sensitivity of the solution to the input uncertain parameters. Additionally, we demonstrate how the multigrid ug4-based solver can be applied as a black-box in the uncertainty quantification framework.

  2. Feature inference with uncertain categorization: Re-assessing Anderson's rational model.

    Science.gov (United States)

    Konovalova, Elizaveta; Le Mens, Gae L

    2017-09-18

    A key function of categories is to help predictions about unobserved features of objects. At the same time, humans are often in situations where the categories of the objects they perceive are uncertain. In an influential paper, Anderson (Psychological Review, 98(3), 409-429, 1991) proposed a rational model for feature inferences with uncertain categorization. A crucial feature of this model is the conditional independence assumption-it assumes that the within category feature correlation is zero. In prior research, this model has been found to provide a poor fit to participants' inferences. This evidence is restricted to task environments inconsistent with the conditional independence assumption. Currently available evidence thus provides little information about how this model would fit participants' inferences in a setting with conditional independence. In four experiments based on a novel paradigm and one experiment based on an existing paradigm, we assess the performance of Anderson's model under conditional independence. We find that this model predicts participants' inferences better than competing models. One model assumes that inferences are based on just the most likely category. The second model is insensitive to categories but sensitive to overall feature correlation. The performance of Anderson's model is evidence that inferences were influenced not only by the more likely category but also by the other candidate category. Our findings suggest that a version of Anderson's model which relaxes the conditional independence assumption will likely perform well in environments characterized by within-category feature correlation.

  3. Pacific salmon extinctions: quantifying lost and remaining diversity.

    Science.gov (United States)

    Gustafson, Richard G; Waples, Robin S; Myers, James M; Weitkamp, Laurie A; Bryant, Gregory J; Johnson, Orlay W; Hard, Jeffrey J

    2007-08-01

    Widespread population extirpations and the consequent loss of ecological, genetic, and life-history diversity can lead to extinction of evolutionarily significant units (ESUs) and species. We attempted to systematically enumerate extinct Pacific salmon populations and characterize lost ecological, life history, and genetic diversity types among six species of Pacific salmon (Chinook [Oncorhynchus tshawytscha], sockeye [O. nerka], coho [O. kisutch], chum [O. keta], and pink salmon [O. gorbuscha] and steelhead trout [O. mykiss]) from the western contiguous United States. We estimated that, collectively, 29% of nearly 1400 historical populations of these six species have been lost from the Pacific Northwest and California since Euro-American contact. Across all species there was a highly significant difference in the proportion of population extinctions between coastal (0.14 extinct) and interior (0.55 extinct) regions. Sockeye salmon (which typically rely on lacustrine habitats for rearing) and stream-maturing Chinook salmon (which stay in freshwater for many months prior to spawning) had significantly higher proportional population losses than other species and maturation types. Aggregate losses of major ecological, life-history, and genetic biodiversity components across all species were estimated at 33%, 15%, and 27%, respectively. Collectively, we believe these population extirpations represent a loss of between 16% and 30% of all historical ESUs in the study area. On the other hand, over two-thirds of historical Pacific salmon populations in this area persist, and considerable diversity remains at all scales. Because over one-third of the remaining populations belong to threatened or endangered species listed under the U.S. Endangered Species Act, it is apparent that a critical juncture has been reached in efforts to preserve what remains of Pacific salmon diversity. It is also evident that persistence of existing, and evolution of future, diversity will depend

  4. Studies on protozoa in ancient remains - A Review

    Directory of Open Access Journals (Sweden)

    Liesbeth Frías

    2013-02-01

    Full Text Available Paleoparasitological research has made important contributions to the understanding of parasite evolution and ecology. Although parasitic protozoa exhibit a worldwide distribution, recovering these organisms from an archaeological context is still exceptional and relies on the availability and distribution of evidence, the ecology of infectious diseases and adequate detection techniques. Here, we present a review of the findings related to protozoa in ancient remains, with an emphasis on their geographical distribution in the past and the methodologies used for their retrieval. The development of more sensitive detection methods has increased the number of identified parasitic species, promising interesting insights from research in the future.

  5. Tuberculosis remains a challenge despite economic growth in Panama.

    Science.gov (United States)

    Tarajia, M; Goodridge, A

    2014-03-01

    Tuberculosis (TB) is a disease associated with inequality, and wise investment of economic resources is considered critical to its control. Panama has recently secured its status as an upper-middle-income country with robust economic growth. However, the prioritisation of resources for TB control remains a major challenge. In this article, we highlight areas that urgently require action to effectively reduce TB burden to minimal levels. Our conclusions suggest the need for fund allocation and a multidisciplinary approach to ensure prompt laboratory diagnosis, treatment assurance and workforce reinforcement, complemented by applied and operational research, development and innovation.

  6. "Recent" macrofossil remains from the Lomonosov Ridge, central Arctic Ocean

    Science.gov (United States)

    Le Duc, Cynthia; de Vernal, Anne; Archambault, Philippe; Brice, Camille; Roberge, Philippe

    2016-04-01

    The examination of surface sediment samples collected from 17 sites along the Lomonosov Ridge at water depths ranging from 737 to 3339 meters during Polarstern Expedition PS87 in 2014 (Stein, 2015), indicates a rich biogenic content almost exclusively dominated by calcareous remains. Amongst biogenic remains, microfossils (planktic and benthic foraminifers, pteropods, ostracods, etc.) dominate but millimetric to centrimetric macrofossils occurred frequently at the surface of the sediment. The macrofossil remains consist of a large variety of taxa, including gastropods, bivalvia, polychaete tubes, scaphopods, echinoderm plates and spines, and fish otoliths. Among the Bivalvia, the most abundant taxa are Portlandia arctica, Hyalopecten frigidus, Cuspidaria glacilis, Policordia densicostata, Bathyarca spp., and Yoldiella spp. Whereas a few specimens are well preserved and apparently pristine, most mollusk shells displayed extensive alteration features. Moreover, most shells were covered by millimeter scale tubes of the serpulid polychaete Spirorbis sp. suggesting transport from low intertidal or subtidal zone. Both the ecological affinity and known geographic distribution of identified bivalvia as named above support the hypothesis of transportation rather than local development. In addition to mollusk shells, more than a hundred fish otoliths were recovered in surface sediments. The otoliths mostly belong to the Gadidae family. Most of them are well preserved and without serpulid tubes attached to their surface, suggesting a local/regional origin, unlike the shell remains. Although recovered at the surface, the macrofaunal assemblages of the Lomonosov Ridge do not necessarily represent the "modern" environments as they may result from reworking and because their occurrence at the surface of the sediment may also be due to winnowing of finer particles. Although the shells were not dated, we suspect that their actual ages may range from modern to several thousands of

  7. The Artificial Leaf: Recent Progress and Remaining Challenges

    Directory of Open Access Journals (Sweden)

    Mark D Symes

    2016-12-01

    Full Text Available The prospect of a device that uses solar energy to split water into H2 and O2 is highly attractive in terms of producing hydrogen as a carbon-neutral fuel. In this mini review, key research milestones that have been reached in this field over the last two decades will be discussed, with special focus on devices that use earth-abundant materials. Finally, the remaining challenges in the development of such “artificial leaves” will be highlighted.

  8. Yellow Fever Remains a Potential Threat to Public Health.

    Science.gov (United States)

    Vasconcelos, Pedro F C; Monath, Thomas P

    2016-08-01

    Yellow fever (YF) remains a serious public health threat in endemic countries. The recent re-emergence in Africa, initiating in Angola and spreading to Democratic Republic of Congo and Uganda, with imported cases in China and Kenya is of concern. There is such a shortage of YF vaccine in the world that the World Health Organization has proposed the use of reduced doses (1/5) during emergencies. In this short communication, we discuss these and other problems including the risk of spread of YF to areas free of YF for decades or never before affected by this arbovirus disease.

  9. Bayesian Estimation of Remaining Useful Life for Wind Turbine Blades

    DEFF Research Database (Denmark)

    Nielsen, Jannie Sønderkær; Sørensen, John Dalsgaard

    2017-01-01

    To optimally plan maintenance of wind turbine blades, knowledge of the degradation processes and the remaining useful life is essential. In this paper, a method is proposed for calibration of a Markov deterioration model based on past inspection data for a range of blades, and updating of the model...... for a specific wind turbine blade, whenever information is available from inspections and/or condition monitoring. Dynamic Bayesian networks are used to obtain probabilities of inspection outcomes for a maximum likelihood estimation of the transition probabilities in the Markov model, and are used again when...

  10. REMAINED DENTAL PARTICLES IN THE JAWS OF EDENTULOUSPATIENTS (ISFAHAN. 1999

    Directory of Open Access Journals (Sweden)

    R MOSHARRAF

    2002-09-01

    Full Text Available Remained teeth and other lesions such as cysts, abcesses and tumors is one of the important problems in edentulous patients. In a cross-sectional study, 330 edentulous patients were evaluated radiographically. The radiographic evaluation of patients revealed the presence of 86 residual roots in 58 radiographs. 17.58% of patients had residual roots & 5.8% of patients had Impacted teeth. 58.1% of residual roots and 45% of impacted teeth were in the maxilla and others were in mandible. Maximum Percentage of residual roots (58.1% and impacted teeth (70% were found in molar region. In this study revealed 23.3% of examined patients had remaining dental fragments. From these patients, 5.76% had impacted teeth and 17.58% had residual roots, and maximum percentage of rooth fragments (58.1% were found in molar region. In similar study by spyropoulus, maximum percentage of root fragments (45.6% reported in molar region and maximum percentage of impacted teeth were found in molar and canine region (41.2% in molar and 41.2 in canine region. In this study, 58.1% of root fragments and 45% of impacted teeth were found in the maxilla but in spyropoulos" report, 71.9% of root fragments and 94.1% of impacted teeth were found in the maxilla.

  11. Prions and lymphoid organs: solved and remaining mysteries.

    Science.gov (United States)

    O'Connor, Tracy; Aguzzi, Adriano

    2013-01-01

    Prion colonization of secondary lymphoid organs (SLOs) is a critical step preceding neuroinvasion in prion pathogenesis. Follicular dendritic cells (FDCs), which depend on both tumor necrosis factor receptor 1 (TNFR1) and lymphotoxin β receptor (LTβR) signaling for maintenance, are thought to be the primary sites of prion accumulation in SLOs. However, prion titers in RML-infected TNFR1 (-/-) lymph nodes and rates of neuroinvasion in TNFR1 (-/-) mice remain high despite the absence of mature FDCs. Recently, we discovered that TNFR1-independent prion accumulation in lymph nodes relies on LTβR signaling. Loss of LTβR signaling in TNFR1 (-/-) lymph nodes coincided with the de-differentiation of high endothelial venules (HEVs)-the primary sites of lymphocyte entry into lymph nodes. These findings suggest that HEVs are the sites through which prions initially invade lymph nodes from the bloodstream. Identification of HEVs as entry portals for prions clarifies a number of previous observations concerning peripheral prion pathogenesis. However, a number of questions still remain: What is the mechanism by which prions are taken up by HEVs? Which cells are responsible for delivering prions to lymph nodes? Are HEVs the main entry site for prions into lymph nodes or do alternative routes also exist? These questions and others are considered in this article.

  12. Mechanical determinants of bone form: insights from skeletal remains.

    Science.gov (United States)

    Ruff, C B

    2005-01-01

    Analysis of skeletal remains from humans living in the past forms an important complement to observational and experimental studies of living humans and animal models. Including earlier humans in such analyses increases the range of variation in both behavior and body size and shape that are represented, and can provide insights into the adaptive potential of the modern human skeleton. I review here a variety of studies of archaeological and paleontological remains that have investigated differences in skeletal structure from a mechanical perspective, focusing in particular on diaphyseal strength of the limb bones. Several conclusions can be drawn from these studies: 1) there has been a decline in overall skeletal strength relative to body size over the course of human evolution that has become progressively steeper in recent millennia, probably due to increased sedentism and technological advancement; 2) differences in pelvic structure and hip mechanical loadings affect femoral shape; 3) activity patterns affect overall strength and shape of both the lower and upper limb bones; and 4) responsiveness to changes in mechanical loading varies between skeletal features (e.g., articulations versus diaphyses) and by age.

  13. Detection of Buried Human Remains Using Bioreporter Fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Vass, A. Dr.; Singleton, G. B.

    2001-10-01

    The search for buried human remains is a difficult, laborious and time-consuming task for law enforcement agencies. This study was conducted as a proof of principle demonstration to test the concept of using bioreporter microorganisms as a means to cover large areas in such a search. These bioreporter microorganisms are affected by a particular component of decaying organic matter that is distinct from decaying vegetation. The diamino compounds cadaverine and putrescine were selected as target compounds for the proof-of-principle investigation, and a search for microorganisms and genes that are responsive to either of these compounds was conducted. One recombinant clone was singled out for characterization based on its response to putrescine. The study results show that small concentrations of putrescine increased expression from this bioreporter construct. Although the level of increase was small (making it difficult to distinguish the signal from background), the results demonstrate the principle that bioreporters can be used to detect compounds resulting from decaying human remains and suggest that a wider search for target compounds should be conducted.

  14. Determination of Remaining Useful Life of Gas Turbine Blade

    Directory of Open Access Journals (Sweden)

    Meor Said Mior Azman

    2016-01-01

    Full Text Available The aim of this research is to determine the remaining useful life of gas turbine blade, using service-exposed turbine blades. This task is performed using Stress Rupture Test (SRT under accelerated test conditions where the applied stresses to the specimen is between 400 MPa to 600 MPa and the test temperature is 850°C. The study will focus on the creep behaviour of the 52000 hours service-exposed blades, complemented with creep-rupture modelling using JMatPro software and microstructure examination using optical microscope. The test specimens, made up of Ni-based superalloy of the first stage turbine blades, are machined based on International Standard (ISO 24. The results from the SRT will be analyzed using these two main equations – Larson-Miller Parameter and Life Fraction Rule. Based on the results of the remaining useful life analysis, the 52000h service-exposed blade has the condition to operate in the range of another 4751 hr to 18362 hr. The microstructure examinations shows traces of carbide precipitation that deteriorate the grain boundaries that occurs during creep process. Creep-rupture life modelling using JMatPro software has shown good agreement with the accelerated creep rupture test with minimal error.

  15. Duplex Alu Screening for Degraded DNA of Skeletal Human Remains

    Directory of Open Access Journals (Sweden)

    Fabian Haß

    2017-10-01

    Full Text Available The human-specific Alu elements, belonging to the class of Short INterspersed Elements (SINEs, have been shown to be a powerful tool for population genetic studies. An earlier study in this department showed that it was possible to analyze Alu presence/absence in 3000-year-old skeletal human remains from the Bronze Age Lichtenstein cave in Lower Saxony, Germany. We developed duplex Alu screening PCRs with flanking primers for two Alu elements, each combined with a single internal Alu primer. By adding an internal primer, the approximately 400–500 bp presence signals of Alu elements can be detected within a range of less than 200 bp. Thus, our PCR approach is suited for highly fragmented ancient DNA samples, whereas NGS analyses frequently are unable to handle repetitive elements. With this analysis system, we examined remains of 12 individuals from the Lichtenstein cave with different degrees of DNA degradation. The duplex PCRs showed fully informative amplification results for all of the chosen Alu loci in eight of the 12 samples. Our analysis system showed that Alu presence/absence analysis is possible in samples with different degrees of DNA degradation and it reduces the amount of valuable skeletal material needed by a factor of four, as compared with a singleplex approach.

  16. Double-shell tank remaining useful life estimates

    Energy Technology Data Exchange (ETDEWEB)

    Anantatmula, R.P., Westinghouse Hanford

    1996-12-02

    The existing 28 double-shell tanks (DSTS) at Hanford are currently planned to continue operation through the year 2028 when disposal schedules show removal of waste. This schedule will place the DSTs in a service life window of 4O to 60 years depending on tank construction date and actual retirement date. This paper examines corrosion- related life-limiting conditions of DSTs and reports the results of remaining useful life models developed for estimating remaining tank life. Three models based on controllable parameters such as temperature, chemistry, and relative humidity are presented for estimates to the year in which a particular DST may receive a breach in the primary tank due to pitting in the liquid or vapor region. Pitting is believed to be the life-limiting condition for DSTs,however, the region of the most aggressive pitting (vapor space or liquid) requires further investigation. The results of the models presented suggest none of the existing DSTs should fail by through-wall pitting until well beyond scheduled retrieval in 2028. The estimates of tank breach years (the year in which a tank may be expected to breach the primary tank wall) range from 2056 for pitting corrosion in the liquid region of tank 104-AW to beyond the next millennium for several tanks in the vapor region.

  17. Radiocarbon analysis of human remains: a review of forensic applications.

    Science.gov (United States)

    Ubelaker, Douglas H

    2014-11-01

    Radiocarbon analysis of organic materials, with the comparison of values with those of the post-1950 modern bomb curve, has proven useful in forensic science to help evaluate the antiquity of evidence. Applications are particularly helpful in the study of human remains, especially with those displaying advanced decomposition of soft tissues. Radiocarbon analysis can reveal if the remains relate to the modern, post-1950 era and if so, also provide information needed to evaluate the death and birth date. Sample selection and interpretation of results must be guided by knowledge of the formation and remodeling of different human tissues, as well as contextual information and the approximate age at death of the individual represented. Dental enamel does not remodel and thus captures dietary radiocarbon values at the time of juvenile formation. Most other human tissues do remodel but at differing rates and therefore collectively offer key information relative to the estimation of the death date. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  18. Homo naledi pelvic remains from the Dinaledi Chamber, South Africa.

    Science.gov (United States)

    VanSickle, Caroline; Cofran, Zachary; García-Martínez, Daniel; Williams, Scott A; Churchill, Steven E; Berger, Lee R; Hawks, John

    2017-11-20

    In the hominin fossil record, pelvic remains are sparse and are difficult to attribute taxonomically when they are not directly associated with craniodental material. Here we describe the pelvic remains from the Dinaledi Chamber in the Rising Star cave system, Cradle of Humankind, South Africa, which has produced hominin fossils of a new species, Homo naledi. Though this species has been attributed to Homo based on cranial and lower limb morphology, the morphology of some of the fragmentary pelvic remains recovered align more closely with specimens attributed to the species Australopithecus afarensis and Australopithecus africanus than they do with those of most (but not all) known species of the genus Homo. As with A. afarensis and A. africanus, H. naledi appears to have had marked lateral iliac flare and either a weakly developed or non-existent acetabulocristal buttress or a distinct, albeit weakly developed, acetabulospinous buttress. At the same time, H. naledi has robust superior pubic and ischiopubic rami and a short ischium with a narrow tuberoacetabular sulcus, similar to those found in modern humans. The fragmentary nature of the Dinaledi pelvic assemblage makes the attribution of sex and developmental age to individual specimens difficult, which in turn diminishes our ability to identify the number of individuals represented in the assemblage. At present, we can only confidently say that the pelvic fossils from Rising Star represent at least four individuals based on the presence of four overlapping right ischial fossils (whereas a minimum of 15 individuals can be identified from the Dinaledi dental assemblage). A primitive, early Australopithecus-like false pelvis combined with a derived Homo-like true pelvis is morphologically consistent with evidence from the lower ribcage and proximal femur of H. naledi. The overall similarity of H. naledi ilia to those of australopiths supports the inference, drawn from the observation of primitive pelvic

  19. Highly efficient DNA extraction method from skeletal remains

    Directory of Open Access Journals (Sweden)

    Irena Zupanič Pajnič

    2011-03-01

    Full Text Available Background: This paper precisely describes the method of DNA extraction developed to acquire high quality DNA from the Second World War skeletal remains. The same method is also used for molecular genetic identification of unknown decomposed bodies in routine forensic casework where only bones and teeth are suitable for DNA typing. We analysed 109 bones and two teeth from WWII mass graves in Slovenia. Methods: We cleaned the bones and teeth, removed surface contaminants and ground the bones into powder, using liquid nitrogen . Prior to isolating the DNA in parallel using the BioRobot EZ1 (Qiagen, the powder was decalcified for three days. The nuclear DNA of the samples were quantified by real-time PCR method. We acquired autosomal genetic profiles and Y-chromosome haplotypes of the bones and teeth with PCR amplification of microsatellites, and mtDNA haplotypes 99. For the purpose of traceability in the event of contamination, we prepared elimination data bases including genetic profiles of the nuclear and mtDNA of all persons who have been in touch with the skeletal remains in any way. Results: We extracted up to 55 ng DNA/g of the teeth, up to 100 ng DNA/g of the femurs, up to 30 ng DNA/g of the tibias and up to 0.5 ng DNA/g of the humerus. The typing of autosomal and YSTR loci was successful in all of the teeth, in 98 % dekalof the femurs, and in 75 % to 81 % of the tibias and humerus. The typing of mtDNA was successful in all of the teeth, and in 96 % to 98 % of the bones. Conclusions: We managed to obtain nuclear DNA for successful STR typing from skeletal remains that were over 60 years old . The method of DNA extraction described here has proved to be highly efficient. We obtained 0.8 to 100 ng DNA/g of teeth or bones and complete genetic profiles of autosomal DNA, Y-STR haplotypes, and mtDNA haplotypes from only 0.5g bone and teeth samples.

  20. Weight references for burned human skeletal remains from Portuguese samples.

    Science.gov (United States)

    Gonçalves, David; Cunha, Eugénia; Thompson, Tim J U

    2013-09-01

    Weight is often one of the few recoverable data when analyzing human cremains but references are still rare, especially for European populations. Mean weights for skeletal remains were thus documented for Portuguese modern cremations of both recently deceased individuals and dry skeletons, and the effect of age, sex, and the intensity of combustion was investigated using both multivariate and univariate statistics. The cremains from fresh cadavers were significantly heavier than the ones from dry skeletons regardless of sex and age cohort (p skeletal weight. The effect of the intensity of combustion in cremains weight was unclear. These weight references may, in some cases, help estimating the minimum number of individuals, the completeness of the skeletal assemblage, and the sex of an unknown individual. © 2013 American Academy of Forensic Sciences.

  1. Psychotherapy for Borderline Personality Disorder: Progress and Remaining Challenges.

    Science.gov (United States)

    Links, Paul S; Shah, Ravi; Eynan, Rahel

    2017-03-01

    The main purpose of this review was to critically evaluate the literature on psychotherapies for borderline personality disorder (BPD) published over the past 5 years to identify the progress with remaining challenges and to determine priority areas for future research. A systematic review of the literature over the last 5 years was undertaken. The review yielded 184 relevant abstracts, and after applying inclusion criteria, 16 articles were fully reviewed based on the articles' implications for future research and/or clinical practice. Our review indicated that patients with various severities benefited from psychotherapy; more intensive therapies were not significantly superior to less intensive therapies; enhancing emotion regulation processes and fostering more coherent self-identity were important mechanisms of change; therapies had been extended to patients with BPD and posttraumatic stress disorder; and more research was needed to be directed at functional outcomes.

  2. Tactile display on the remaining hand for unilateral hand amputees

    Directory of Open Access Journals (Sweden)

    Li Tao

    2016-09-01

    Full Text Available Human rely profoundly on tactile feedback from fingertips to interact with the environment, whereas most hand prostheses used in clinics provide no tactile feedback. In this study we demonstrate the feasibility to use a tactile display glove that can be worn by a unilateral hand amputee on the remaining healthy hand to display tactile feedback from a hand prosthesis. The main benefit is that users could easily distinguish the feedback for each finger, even without training. The claimed advantage is supported by preliminary tests with healthy subjects. This approach may lead to the development of effective and affordable tactile display devices that provide tactile feedback for individual fingertip of hand prostheses.

  3. Reducing Susceptibility to Courtesy Stigma.

    Science.gov (United States)

    Bachleda, Catherine L; El Menzhi, Leila

    2017-04-19

    In light of the chronic shortage of health professionals willing to care for HIV/AIDS patients, and rising epidemics in many Muslim countries, this qualitative study examined susceptibility and resistance to courtesy stigma as experienced by nurses, doctors, and social workers in Morocco. Forty-nine in-depth interviews provided rich insights into the process of courtesy stigma and how it is managed, within the context of interactions with Islam, interactions within the workplace (patients, other health professionals), and interactions outside the workplace (the general public, friends, and family). Theoretically, the findings extend understanding of courtesy stigma and the dirty work literature. The findings also offer practical suggestions for the development of culturally appropriate strategies to reduce susceptibility to courtesy stigmatization. This study represents the first to explore courtesy stigma as a process experienced by health professionals providing HIV/AIDS care in an Islamic country.

  4. Reidentification of avian embryonic remains from the cretaceous of mongolia.

    Science.gov (United States)

    Varricchio, David J; Balanoff, Amy M; Norell, Mark A

    2015-01-01

    Embryonic remains within a small (4.75 by 2.23 cm) egg from the Late Cretaceous, Mongolia are here re-described. High-resolution X-ray computed tomography (HRCT) was used to digitally prepare and describe the enclosed embryonic bones. The egg, IGM (Mongolian Institute for Geology, Ulaanbaatar) 100/2010, with a three-part shell microstructure, was originally assigned to Neoceratopsia implying extensive homoplasy among eggshell characters across Dinosauria. Re-examination finds the forelimb significantly longer than the hindlimbs, proportions suggesting an avian identification. Additional, postcranial apomorphies (strut-like coracoid, cranially located humeral condyles, olecranon fossa, slender radius relative to the ulna, trochanteric crest on the femur, and ulna longer than the humerus) identify the embryo as avian. Presence of a dorsal coracoid fossa and a craniocaudally compressed distal humerus with a strongly angled distal margin support a diagnosis of IGM 100/2010 as an enantiornithine. Re-identification eliminates the implied homoplasy of this tri-laminate eggshell structure, and instead associates enantiornithine birds with eggshell microstructure composed of a mammillary, squamatic, and external zones. Posture of the embryo follows that of other theropods with fore- and hindlimbs folded parallel to the vertebral column and the elbow pointing caudally just dorsal to the knees. The size of the egg and embryo of IGM 100/2010 is similar to the two other Mongolian enantiornithine eggs. Well-ossified skeletons, as in this specimen, characterize all known enantiornithine embryos suggesting precocial hatchlings, comparing closely to late stage embryos of modern precocial birds that are both flight- and run-capable upon hatching. Extensive ossification in enantiornithine embryos may contribute to their relatively abundant representation in the fossil record. Neoceratopsian eggs remain unrecognized in the fossil record.

  5. Reidentification of avian embryonic remains from the cretaceous of mongolia.

    Directory of Open Access Journals (Sweden)

    David J Varricchio

    Full Text Available Embryonic remains within a small (4.75 by 2.23 cm egg from the Late Cretaceous, Mongolia are here re-described. High-resolution X-ray computed tomography (HRCT was used to digitally prepare and describe the enclosed embryonic bones. The egg, IGM (Mongolian Institute for Geology, Ulaanbaatar 100/2010, with a three-part shell microstructure, was originally assigned to Neoceratopsia implying extensive homoplasy among eggshell characters across Dinosauria. Re-examination finds the forelimb significantly longer than the hindlimbs, proportions suggesting an avian identification. Additional, postcranial apomorphies (strut-like coracoid, cranially located humeral condyles, olecranon fossa, slender radius relative to the ulna, trochanteric crest on the femur, and ulna longer than the humerus identify the embryo as avian. Presence of a dorsal coracoid fossa and a craniocaudally compressed distal humerus with a strongly angled distal margin support a diagnosis of IGM 100/2010 as an enantiornithine. Re-identification eliminates the implied homoplasy of this tri-laminate eggshell structure, and instead associates enantiornithine birds with eggshell microstructure composed of a mammillary, squamatic, and external zones. Posture of the embryo follows that of other theropods with fore- and hindlimbs folded parallel to the vertebral column and the elbow pointing caudally just dorsal to the knees. The size of the egg and embryo of IGM 100/2010 is similar to the two other Mongolian enantiornithine eggs. Well-ossified skeletons, as in this specimen, characterize all known enantiornithine embryos suggesting precocial hatchlings, comparing closely to late stage embryos of modern precocial birds that are both flight- and run-capable upon hatching. Extensive ossification in enantiornithine embryos may contribute to their relatively abundant representation in the fossil record. Neoceratopsian eggs remain unrecognized in the fossil record.

  6. Premortal data in the process of skeletal remains identification

    Directory of Open Access Journals (Sweden)

    Marinković Nadica

    2012-01-01

    Full Text Available Background/Aim. The basic task of a forensic examiner during the exhumation of mass graves or in mass accidents is to establish identity of a person. The results obtained through these procedures depend on the level of perceptibility of post mortal changes and they are compared with premortal data obtained from family members of those missing or killed. Experience with exhumations has shown significant differences between the results obtained through exhumation and the premortal data. The aim of the study was to suggest the existance of the difference between premortal data and the results obtained by exhumation regarding the some parameters, as well as to direct premortal data colection to the specific skeletal forms. Methods. We performed comparative analysis of the results of exhumation of skeletal remains in a mass grave and the premortal data concerning the identified persons. The least number of individuals in this mass grave was calculated according to the upper parts of the right femur and it helped in calculating the smallest number of individuals in mass graves to be 48. A total of 27 persons were identified. Sex was determined by metrics and morphology of the pelvis. Personal age in the moment of death was determined by morphology features of groin symphisis and morphology of sternal edge of ribs and other parts of scelets observations. The hight was calculated as average results of length of long bones and Rollet coefficients. Results. There was a complete match in terms of sex and age matched within an interval that could be established based on the skeletal remains. All the other parameters were different, however, which made identification significantly more difficult. Conclusion. The premortal data is an important element of identification process and it should be obtained by the forensic doctor and directed towards more detailed examination of the skeletal system.

  7. Antimycotics susceptibility testing of dermatophytes

    Directory of Open Access Journals (Sweden)

    Arsić-Arsenijević Valentina

    2010-01-01

    Full Text Available Dermatophytes are moulds that produce infections of the skin, hair and nails of humans and animals. The most common forms among these infections are onychomycosis and tinea pedis affecting 20% of world population. These infections are usually chronic. The treatment of dermatophytoses tends to be prolonged partly because available treatments are not very effective. Antifungal drug consumption and public health expenditure are high worldwide, as well as in Serbia. For adequate therapy, it is necessary to prove infection by isolation of dermatophytes and to test the antifungal susceptibility of isolates. Susceptibility testing is important for the resistance monitoring, epidemiological research and to compare in vitro activities of new antifungal agents. The diffusion and dilution methods of susceptibility tests are used, and technical issues of importance for the proper performance and interpretation of test results are published in the document E.DEF 9.1 (EUCAST and M38-A2 (CLSI. The aim of our paper is to promptly inform the public about technical achievements in this area, as well as the new organization of laboratory for medical mycology in our country. The formation of laboratory networks coordinated by the National Reference Laboratory for the cause of mycosis need to enable interlaboratory studies and further standardization of methods for antifungal susceptibility testing of dermatophytes, reproducibility of tests and clinical correlation monitoring (MIK values and clinical outcome of dermatophytosis. The importance of the new organization is expected efficient improvement in the dermatophytosis therapy at home, better quality of patient's life and the reduction of the cost of treatment.

  8. Antibiotic susceptibility of Atopobium vaginae

    Directory of Open Access Journals (Sweden)

    Verschraegen Gerda

    2006-03-01

    Full Text Available Abstract Background Previous studies have indicated that a recently described anaerobic bacterium, Atopobium vaginae is associated with bacterial vaginosis (BV. Thus far the four isolates of this fastidious micro-organism were found to be highly resistant to metronidazole and susceptible for clindamycin, two antibiotics preferred for the treatment of BV. Methods Nine strains of Atopobium vaginae, four strains of Gardnerella vaginalis, two strains of Lactobacillus iners and one strain each of Bifidobacterium breve, B. longum, L. crispatus, L. gasseri and L. jensenii were tested against 15 antimicrobial agents using the Etest. Results All nine strains of A. vaginae were highly resistant to nalidixic acid and colistin while being inhibited by low concentrations of clindamycin (range: G. vaginalis strains were also susceptible for clindamycin ( 256 μg/ml but susceptible to clindamycin (0.023 – 0.125 μg/ml. Conclusion Clindamycin has higher activity against G. vaginalis and A. vaginae than metronidazole, but not all A. vaginae isolates are metronidazole resistant, as seemed to be a straightforward conclusion from previous studies on a more limited number of strains.

  9. A putative Lynch syndrome family carrying MSH2 and MSH6 variants of uncertain significance-functional analysis reveals the pathogenic one

    DEFF Research Database (Denmark)

    Kantelinen, Jukka; Hansen, Thomas V O; Kansikas, Minttu

    2011-01-01

    Inherited pathogenic mutations in the mismatch repair (MMR) genes, MSH2, MLH1, MSH6, and PMS2 predispose to Lynch syndrome (LS). However, the finding of a variant or variants of uncertain significance (VUS) in affected family members complicates the risk assessment. Here, we describe a putative LS...... family carrying VUS in both MSH2 (c.2768T>A, p.Val923Glu) and MSH6 (c.3563G>A, p.Ser1188Asn). Two colorectal cancer (CRC) patients were studied for mutations and identified as carriers of both variants. In spite of a relatively high mean age of cancer onset (59.5 years) in the family, many CRC patients...... and the tumor pathological data suggested that the missense variation in MSH2, the more common susceptibility gene in LS, would be the predisposing alteration. However, MSH2 VUS was surprisingly found to be MMR proficient in an in vitro MMR assay and a tolerant alteration in silico. By supplying evidence...

  10. Calculation note for an underground leak which remains underground

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, H.J.

    1997-05-20

    This calculation note supports the subsurface leak accident scenario which remains subsurface. It is assumed that a single walled pipe carrying waste from tank 106-C ruptures, releasing the liquid waste into the soil. In this scenario, the waste does not form a surface pool, but remains subsurface. However, above the pipe is a berm, 0.762 m (2.5 ft) high and 2.44 m (8 ft) wide, and the liquid released from the leak rises into the berm. The slurry line, which transports a source term of higher activity than the sluice line, leaks into the soil at a rate of 5% of the maximum flow rate of 28.4 L/s (450 gpm) for twelve hours. The dose recipient was placed a perpendicular distance of 100 m from the pipe. Two source terms were considered, mitigated and unmitigated release as described in section 3.4.1 of UANF-SD-WM-BIO-001, Addendum 1. The unmitigated consisted of two parts of AWF liquid and one part AWF solid. The mitigated release consisted of two parts SST liquid, eighteen parts AWF liquid, nine parts SST solid, and one part AWF solid. The isotopic breakdown of the release in these cases is presented. Two geometries were considered in preliminary investigations, disk source, and rectangular source. Since the rectangular source results from the assumption that the contamination is wicked up into the berm, only six inches of shielding from uncontaminated earth is present, while the disk source, which remains six inches below the level of the surface of the land is often shielded by a thick shield due to the slant path to the dose point. For this reason, only the rectangular source was considered in the final analysis. The source model was a rectangle 2.134 m (7 ft) thick, 0.6096 m (2 ft) high, and 130.899 m (131 ft) long. The top and sides of this rectangular source was covered with earth of density 1.6 g/cm{sup 3} to a thickness of 15.24 cm (6 in). This soil is modeled as 40% void space. The source consisted of earth of the same density with the void spaces filled with

  11. Mineralized Remains of Morphotypes of Filamentous Cyanobacteria in Carbonaceous Meteorites

    Science.gov (United States)

    Hoover, Richard B.

    2005-01-01

    ) investigations of freshly fractured interior surfaces of carbonaceous meteorites, terrestrial rocks, and recent microbial extremophiles and filamentous cyanobacteria. These studies have resulted in the detection in a several carbonaceous meteorites of the mineralized remains of a wide variety of complex filamentous trichomic microorganisms. These embedded forms are consistent in size and microstructure with well-preserved morphotypes of mat- forming filamentous trichomic cyanobacteria and the degraded remains of microfibrils of cyanobacterial sheaths. We present the results of comparative imaging studies and EDAX elemental analyses of recent cyanobacteria (e.g. Calothrix, Oscillatoria, and Lyngbya) that are similar in size, morphology and microstructure to morphotypes found embedded in meteorites. EDAX elemental studies reveal that forms found in carbonaceous meteorites often have highly carbonized sheaths in close association with permineralized filaments, trichomes and microbial cells. Ratios of critical bioelements (C:O, C:N, C:P, and C:S) reveal dramatic differences between microfossils in Earth rocks and meteorites and in filaments, trichomes, hormogonia, and cells of recent cyanobacteria.

  12. Future Remains: Industrial Heritage at the Hanford Plutonium Works

    Science.gov (United States)

    Freer, Brian

    This dissertation argues that U.S. environmental and historic preservation regulations, industrial heritage projects, history, and art only provide partial frameworks for successfully transmitting an informed story into the long range future about nuclear technology and its related environmental legacy. This argument is important because plutonium from nuclear weapons production is toxic to humans in very small amounts, threatens environmental health, has a half-life of 24, 110 years and because the industrial heritage project at Hanford is the first time an entire U.S. Department of Energy weapons production site has been designated a U.S. Historic District. This research is situated within anthropological interest in industrial heritage studies, environmental anthropology, applied visual anthropology, as well as wider discourses on nuclear studies. However, none of these disciplines is really designed or intended to be a completely satisfactory frame of reference for addressing this perplexing challenge of documenting and conveying an informed story about nuclear technology and its related environmental legacy into the long range future. Others have thought about this question and have made important contributions toward a potential solution. Examples here include: future generations movements concerning intergenerational equity as evidenced in scholarship, law, and amongst Native American groups; Nez Perce and Confederated Tribes of the Umatilla Indian Reservation responses to the Hanford End State Vision and Hanford's Canyon Disposition Initiative; as well as the findings of organizational scholars on the advantages realized by organizations that have a long term future perspective. While these ideas inform the main line inquiry of this dissertation, the principal approach put forth by the researcher of how to convey an informed story about nuclear technology and waste into the long range future is implementation of the proposed Future Remains clause, as

  13. Measurements of temperature dependence of 'localized susceptibility'

    CERN Document Server

    Shiozawa, H; Ishii, H; Takayama, Y; Obu, K; Muro, T; Saitoh, Y; Matsuda, T D; Sugawara, H; Sato, H

    2003-01-01

    The magnetic susceptibility of some rare-earth compounds is estimated by measuring magnetic circular dichroism (MCD) of rare-earth 3d-4f absorption spectra. The temperature dependence of the magnetic susceptibility obtained by the MCD measurement is remarkably different from the bulk susceptibility in most samples, which is attributed to the strong site selectivity of the core MCD measurement.

  14. Fuzzy Approximation-Based Global Pinning Synchronization Control of Uncertain Complex Dynamical Networks.

    Science.gov (United States)

    Li, Xiao-Jian; Yang, Guang-Hong

    2017-04-01

    This paper is concerned with the global pinning synchronization problem of uncertain complex dynamical networks with communication constraints. First, an adaptive fuzzy controller is designed within a given compact set. In addition, a robust controller is introduced outside the compact set to pull back the system states. Then, a new pinning control scheme is given such that the global synchronization can be ensured. Moreover, via the Lyapunov theory and graph theory, the synchronization errors are proved to be asymptotically convergent. Especially, in an uncertainty-free environment, the proposed control scheme includes two easy-to-implement pinning control strategies as special cases, which improve the existing results from the view point of reducing the number of feedback controllers. Finally, two simulation examples are provided to validate the theoretical results.

  15. PID Based on Attractive Ellipsoid Method for Dynamic Uncertain and External Disturbances Rejection in Mechanical Systems

    Directory of Open Access Journals (Sweden)

    Jesus Patricio Ordaz Oliver

    2015-01-01

    Full Text Available This paper presents a stability analysis for LNDS (Lagrangian nonlinear dynamical systems with dynamic uncertain using a PID controller with external disturbances rejection based on attractive ellipsoid methods, since the PID-CT (proportional integral derivative computed torque compensator has been used for the nonlinear trajectory tracking of an LNDS, when there are external perturbations and system uncertainties. The global system convergence of the trivial solution has not been proved. In this sense, we propose an approach to find the gains of the nonlinear PID-CT controller to guarantee the boundedness of the trivial solution by means of the concept of the UUB (uniform-ultimately bounded stability. In order to show the effectiveness of the methodology proposed, we applied it in a real 2-DoF robot system.

  16. A (Creative) Portrait of the Uncertain Individual: Self-Uncertainty and Individualism Enhance Creative Generation.

    Science.gov (United States)

    Rios, Kimberly; Markman, Keith D; Schroeder, Juliana; Dyczewski, Elizabeth A

    2014-08-01

    Building on findings that self-uncertainty motivates attempts to restore certainty about the self, particularly in ways that highlight one's distinctiveness from others, we show that self-uncertainty, relative to uncertainty in general, increases creative generation among individualists. In Studies 1 to 3, high (but not low) individualists performed better on a creative generation task after being primed with self-uncertainty as opposed to general uncertainty. In Study 4, this effect emerged only among those who were told that the task measured creative as opposed to analytical thinking, suggesting that the positive effects of self-uncertainty on performance are specific to tasks that bolster perceptions of uniqueness. In Study 5, self-uncertain individualists experienced a restoration of self-clarity after being induced to think about themselves as more (vs. less) creative. Implications for compensatory responses to self-uncertainty and factors that influence creativity are discussed. © 2014 by the Society for Personality and Social Psychology, Inc.

  17. Memory State Feedback RMPC for Multiple Time-Delayed Uncertain Linear Systems with Input Constraints

    Directory of Open Access Journals (Sweden)

    Wei-Wei Qin

    2014-01-01

    Full Text Available This paper focuses on the problem of asymptotic stabilization for a class of discrete-time multiple time-delayed uncertain linear systems with input constraints. Then, based on the predictive control principle of receding horizon optimization, a delayed state dependent quadratic function is considered for incorporating MPC problem formulation. By developing a memory state feedback controller, the information of the delayed plant states can be taken into full consideration. The MPC problem is formulated to minimize the upper bound of infinite horizon cost that satisfies the sufficient conditions. Then, based on the Lyapunov-Krasovskii function, a delay-dependent sufficient condition in terms of linear matrix inequality (LMI can be derived to design a robust MPC algorithm. Finally, the digital simulation results prove availability of the proposed method.

  18. Decision Making in Uncertain Rural Scenarios by means of Fuzzy TOPSIS Method

    Directory of Open Access Journals (Sweden)

    Eva Armero

    2011-01-01

    Full Text Available A great deal of uncertain information which is difficult to quantify is taken into account by farmers and experts in the enterprise when making decisions. We are interested in the problems of the implementation of a rabbit-breeding farm. One of the first decisions to be taken refers to the design or type of structure for housing the animals, which is determined by the level of environmental control sought to be maintained in its interior. A farmer was consulted, and his answers were incorporated into the analysis, by means of the fuzzy TOPSIS methodology. The main purpose of this paper is to study the problem by means of the fuzzy TOPSIS method as multicriteria decision making, when the information was given in linguistic terms.

  19. Connectivity-Preserving Approach for Distributed Adaptive Synchronized Tracking of Networked Uncertain Nonholonomic Mobile Robots.

    Science.gov (United States)

    Yoo, Sung Jin; Park, Bong Seok

    2017-09-06

    This paper addresses a distributed connectivity-preserving synchronized tracking problem of multiple uncertain nonholonomic mobile robots with limited communication ranges. The information of the time-varying leader robot is assumed to be accessible to only a small fraction of follower robots. The main contribution of this paper is to introduce a new distributed nonlinear error surface for dealing with both the synchronized tracking and the preservation of the initial connectivity patterns among nonholonomic robots. Based on this nonlinear error surface, the recursive design methodology is presented to construct the approximation-based local adaptive tracking scheme at the robot dynamic level. Furthermore, a technical lemma is established to analyze the stability and the connectivity preservation of the total closed-loop control system in the Lyapunov sense. An example is provided to illustrate the effectiveness of the proposed methodology.

  20. Adaptive fuzzy switched control design for uncertain nonholonomic systems with input nonsmooth constraint

    Science.gov (United States)

    Li, Yongming; Tong, Shaocheng

    2016-10-01

    In this paper, a fuzzy adaptive switched control approach is proposed for a class of uncertain nonholonomic chained systems with input nonsmooth constraint. In the control design, an auxiliary dynamic system is designed to address the input nonsmooth constraint, and an adaptive switched control strategy is constructed to overcome the uncontrollability problem associated with x0(t0) = 0. By using fuzzy logic systems to tackle unknown nonlinear functions, a fuzzy adaptive control approach is explored based on the adaptive backstepping technique. By constructing the combination approximation technique and using Young's inequality scaling technique, the number of the online learning parameters is reduced to n and the 'explosion of complexity' problem is avoid. It is proved that the proposed method can guarantee that all variables of the closed-loop system converge to a small neighbourhood of zero. Two simulation examples are provided to illustrate the effectiveness of the proposed control approach.

  1. Towards a Framework for Self-Adaptive Reliable Network Services in Highly-Uncertain Environments

    DEFF Research Database (Denmark)

    Grønbæk, Lars Jesper; Schwefel, Hans-Peter; Ceccarelli, Andrea

    2010-01-01

    to improve resilience of end-node services. In this paper we present a framework, called ODDR (Observation, Diagnosis, Decision, Remediation), for improving resilience of network based services through integration of self-adaptive monitoring services, network diagnosis, decision actions, and finally......In future inhomogeneous, pervasive and highly dynamic networks, end-nodes may often only rely on unreliable and uncertain observations to diagnose hidden network states and decide upon possible remediation actions. Inherent challenges exists to identify good and timely decision strategies...... execution (and monitoring) of remediation actions. We detail the motivations to the ODDR design, then we present its architecture, and finally we describe our current activities towards the realization and assessment of the framework services and the main results currently achieved....

  2. Dynamical Adaptive Integral Sliding Backstepping Control of Nonlinear Nontriangular Uncertain Systems

    Directory of Open Access Journals (Sweden)

    Mahmood Pervaiz

    2014-01-01

    Full Text Available We present a control strategy for nonlinear nontriangular uncertain systems. The proposed control method is a synergy between the dynamic adaptive backstepping (DAB and integral sliding mode (ISM and is referred to as DAB-ISMC. Our main objective is to find a recursive procedure to transform a nontriangular system into an implementable form that enables designing a control law which almost eliminates the reaching-phase. The proposed method further facilitates minimization of chattering which is believed to be a shortcoming of the sliding mode control. In this methodology, the ISM, as an integrated subsystem of DAB, is introduced at the final stage of backstepping. This strategy works very well to obtain a system that is robust against model imperfections, matching and unmatching uncertainties. The DAB-ISMC method is applied on a continuous stirred tank reactor (CSTR and simulation results obtained on Matlab are found to be very promising.

  3. Sensitivity analysis to compute advanced stochastic problems in uncertain and complex electromagnetic environments

    Directory of Open Access Journals (Sweden)

    S. Lalléchère

    2012-10-01

    Full Text Available This paper deals with the advanced integration of uncertainties in electromagnetic interferences (EMI and electromagnetic compatibility (EMC problems.   In this context,  the Monte Carlo formalism may provide a reliable reference to proceed to statistical assessments.   After all, other  less  expensive  and  efficient  techniques  have  been implemented more recently (the unscented transform and stochastic collocation methods for instance and will be illustrated through uncertain EMC problems. Finally, we will present how the use of sensitivity analysis techniques may offer an efficient complement to rough statistical or stochastic studies.

  4. H∞ synchronization of uncertain fractional order chaotic systems: adaptive fuzzy approach.

    Science.gov (United States)

    Lin, Tsung-Chih; Kuo, Chia-Hao

    2011-10-01

    This paper presents a novel adaptive fuzzy logic controller (FLC) equipped with an adaptive algorithm to achieve H(∞) synchronization performance for uncertain fractional order chaotic systems. In order to handle the high level of uncertainties and noisy training data, a desired synchronization error can be attenuated to a prescribed level by incorporating fuzzy control design and H(∞) tracking approach. Based on a Lyapunov stability criterion, not only the performance of the proposed method is satisfying with an acceptable synchronization error level, but also a rather simple stability analysis is performed. The simulation results signify the effectiveness of the proposed control scheme. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

  5. Robust H∞ control of uncertain systems with two additive time-varying delays

    Science.gov (United States)

    Syed, Ali M.; Saravanakumar, R.

    2015-09-01

    This paper is concerned with the problem of delay-dependent robust H∞ control for a class of uncertain systems with two additive time-varying delays. A new suitable Lyapunov-Krasovskii functional (LKF) with triple integral terms is constructed and a tighter upper bound of the derivative of the LKF is derived. By applying a convex optimization technique, new delay-dependent robust H∞ stability criteria are derived in terms of linear matrix inequalities (LMI). Based on the stability criteria, a state feedback controller is designed such that the closed-loop system is asymptotically stable. Finally, numerical examples are given to illustrate the effectiveness of the proposed method. Comparison results show that our results are less conservative than the existing methods. Project supported by the Fund from the Department of Science and Technology of India (Grant No. SR/FTP/MS-039/2011).

  6. 'A variant of uncertain significance' and the proliferation of human disease gene databases

    Directory of Open Access Journals (Sweden)

    Nelson David R

    2005-03-01

    Full Text Available Abstract The rapid accumulation of mutation data has led to the creation of nearly 300 locus-specific mutation databases. These sites may contain a few dozen to almost 20,000 mutations for a given gene. Many of the mutations are uncharacterised and have no known effects on the gene product, the 'variant of uncertain significance'. Here, the statistics of mutation distribution are examined for six different gene databases: BRCA1 and BRCA2, haemoglobin-beta (HBB, HPRT1, CFTR and TP53. The percentage of all possible point mutations for a protein (the mutation space is calculated for each gene and the question 'How much mutation data is enough?' is raised.

  7. Impulsive people have a compulsion for immediate gratification-certain or uncertain.

    Science.gov (United States)

    Białaszek, Wojciech; Gaik, Maciej; McGoun, Elton; Zielonka, Piotr

    2015-01-01

    Impulsivity has been defined as choosing the smaller more immediate reward over a larger more delayed reward. The purpose of this research was to gain a deeper understanding of the mental processes involved in the decision making. We examined participants' rates of delay discounting and probability discounting to determine their correlation with time-probability trade-offs. To establish the time-probability trade-off rate, participants adjusted a risky, immediate payoff to a delayed, certain payoff. In effect, this yielded a probability equivalent of waiting time. We found a strong, positive correlation between delay discount rates and the time-probability trade-offs. This means that impulsive people have a compulsion for immediate gratification, independent of whether the immediate reward is certain or uncertain. Thus, they seem not to be concerned with risk but rather with time.

  8. Impulsive people have a compulsion for immediate gratification - certain or uncertain.

    Directory of Open Access Journals (Sweden)

    Wojciech eBiałaszek

    2015-05-01

    Full Text Available Impulsivity has been defined as choosing the smaller more immediate reward over a larger more delayed reward. The purpose of this research was to gain a deeper understanding of the mental processes involved in the decision making. We examined participants’ rates of delay discounting and probability discounting to determine their correlation with time-probability trade-offs. To establish the time-probability trade-off rate, participants adjusted a risky, immediate payoff to a delayed, certain payoff. In effect, this yielded a probability equivalent of waiting time. We found a strong, positive correlation between delay discount rates and the time-probability trade-offs. This means that impulsive people have a compulsion for immediate gratification, independent of whether the immediate reward is certain or uncertain. Thus, they seem not to be concerned with risk but rather with time.

  9. Robust H∞ Filtering for a Class of Uncertain Markovian Jump Systems with Time Delays

    Directory of Open Access Journals (Sweden)

    Yi Yang

    2013-01-01

    Full Text Available This paper studies the problem of robust H∞ filtering for a class of uncertain time-delay systems with Markovian jumping parameters. The system under consideration is subject to norm-bounded time-varying parameter uncertainties. The problem to be addressed is the design of a Markovian jump filter such that the filter error dynamics are stochastically stable and a prescribed bound on the ℒ2-induced gain from the noise signals to the filter error is guaranteed for all admissible uncertainties. A sufficient condition for the existence of the desired robust H∞ filter is given in terms of two sets of coupled algebraic Riccati inequalities. When these algebraic Riccati inequalities are feasible, the expression of a desired H∞ filter is also presented. Finally, an illustrative numerical example is provided.

  10. ABC Classification of Risk Factors in Production Supply Chains with Uncertain Data

    Directory of Open Access Journals (Sweden)

    Aleksandar Vujović

    2017-01-01

    Full Text Available The problem of classification of risk factors in an uncertain environment is part of the risk management problem, which has a critical effect on the competitive advantage of production supply chain. The severities of consequences, their relative importance, and the frequency of occurrence of risk factors are defined by risk management team, depending on their experience and the results of good practice. Fuzzy rating of the severities of consequences and the frequency of occurrence of risk factors are described by linguistic expressions, which are modeled by triangular fuzzy numbers. The risk values, obtained by the materialization of the identified risk factors, are given precisely with the usage of fuzzy algebra rules. The classification criterion is defined as the distance between current risk value and extreme risk values. The proposed model enables determination of the priorities of risk factors. It is illustrated by an example with real-life data from a production supply chain in auto industry.

  11. Robust constrained waveform design for MIMO radar with uncertain steering vectors

    Science.gov (United States)

    Yu, Xianxiang; Cui, Guolong; Piezzo, Marco; Iommelli, Salvatore; Kong, Lingjiang

    2017-01-01

    This paper considers the robust waveform design of multiple-input multiple-output (MIMO) radar to enhance targets detection in the presence of signal-dependent interferences assuming the knowledge of steering vectors is imprecise. Specifically, resorting to semidefinite programming (SDP)-related technique, we first maximize the worst-case signal-to-interference-plus-noise ratio (SINR) over uncertain region to optimize waveform covariance matrix forcing a uniform elemental power requirement. Then, based on least square (LS) approach, we devise the waveform accounting for constant modulus and similarity constraints by the obtained waveform covariance matrix using cyclic algorithm (CA). Finally, we assess the effectiveness of the proposed technique through numerical simulations in terms of non-uniform point-like clutter and uniform clutter.

  12. Three-dimensional source tracking in an uncertain environment via Bayesian marginalization.

    Science.gov (United States)

    Tollefsen, Dag; Dosso, Stan E

    2010-09-01

    This paper develops a non-linear Bayesian marginalization approach for three-dimensional source tracking in shallow water with uncertain environmental properties. The algorithm integrates the posterior probability density via a combination of Metropolis-Hastings sampling over environmental and bearing model parameters and Gibbs sampling over source range/depth, with track constraints on source velocity applied. Marginal distributions for source range/depth and source bearing are derived, with source position uncertainties estimated from the distributions. The Viterbi algorithm is applied to obtain the most probable three-dimensional track. The approach is applied to experimental narrowband data recorded on a bottom-moored horizontal line array in the Barents Sea.

  13. Political Regimes in Central Asia: Crisis of Legitimacy, Political Violence and Uncertain Prospects

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Djalili

    2005-10-01

    Full Text Available This article analyses the present-day transition and political context of each of the states that comprise the former Soviet region of Central Asia since their independence: the internal changes they have undergone, the creation of their own institutions and regional and international relations. This evolution, especially with regard to the deficiencies in democracy and legitimacy of the majority of the current governments, based, in many cases, on personalist, authoritarian regimes, points to an uncertain future for a region in which, too frequently, its rulers have used all the means at their disposal (persecution of political opposition, disregard for human rights, constraint of the mass media and NGOs, etc. to guarantee their continuance in power. This article also includes an analysis of the most recent events, such as the Andijan (Uzbekistan massacre, the‘revolution’ without changes in Kyrgyzstan, and the authoritarian drift of Turkmenistan, which leads to conclusions filled with uncertainties for future political scenarios.

  14. Quantifying uncertainty in Gulf of Mexico forecasts stemming from uncertain initial conditions

    KAUST Repository

    Iskandarani, Mohamed

    2016-06-09

    Polynomial Chaos (PC) methods are used to quantify the impacts of initial conditions uncertainties on oceanic forecasts of the Gulf of Mexico circulation. Empirical Orthogonal Functions are used as initial conditions perturbations with their modal amplitudes considered as uniformly distributed uncertain random variables. These perturbations impact primarily the Loop Current system and several frontal eddies located in its vicinity. A small ensemble is used to sample the space of the modal amplitudes and to construct a surrogate for the evolution of the model predictions via a nonintrusive Galerkin projection. The analysis of the surrogate yields verification measures for the surrogate\\'s reliability and statistical information for the model output. A variance analysis indicates that the sea surface height predictability in the vicinity of the Loop Current is limited to about 20 days. © 2016. American Geophysical Union. All Rights Reserved.

  15. Nonsingular Terminal Sliding Mode Control of Uncertain Second-Order Nonlinear Systems

    Directory of Open Access Journals (Sweden)

    Minh-Duc Tran

    2015-01-01

    Full Text Available This paper presents a high-performance nonsingular terminal sliding mode control method for uncertain second-order nonlinear systems. First, a nonsingular terminal sliding mode surface is introduced to eliminate the singularity problem that exists in conventional terminal sliding mode control. By using this method, the system not only can guarantee that the tracking errors reach the reference value in a finite time with high-precision tracking performance but also can overcome the complex-value and the restrictions of the exponent (the exponent should be fractional number with an odd numerator and an odd denominator in traditional terminal sliding mode. Then, in order to eliminate the chattering phenomenon, a super-twisting higher-order nonsingular terminal sliding mode control method is proposed. The stability of the closed-loop system is established using the Lyapunov theory. Finally, simulation results are presented to illustrate the effectiveness of the proposed method.

  16. A guide for functional analysis of BRCA1 variants of uncertain significance

    DEFF Research Database (Denmark)

    Millot, Gaël A; Carvalho, Marcelo A; Caputo, Sandrine M

    2012-01-01

    Germline mutations in the tumor suppressor gene BRCA1 confer an estimated lifetime risk of 56-80% for breast cancer and 15-60% for ovarian cancer. Since the mid 1990s when BRCA1 was identified, genetic testing has revealed over 1,500 unique germline variants. However, for a significant number...... of these variants, the effect on protein function is unknown making it difficult to infer the consequences on risks of breast and ovarian cancers. Thus, many individuals undergoing genetic testing for BRCA1 mutations receive test results reporting a variant of uncertain clinical significance (VUS), leading...... to issues in risk assessment, counseling, and preventive care. Here, we describe functional assays for BRCA1 to directly or indirectly assess the impact of a variant on protein conformation or function and how these results can be used to complement genetic data to classify a VUS as to its clinical...

  17. Robust Fusion Filtering for Multisensor Time-Varying Uncertain Systems: The Finite Horizon Case

    Directory of Open Access Journals (Sweden)

    Xiaoliang Feng

    2016-01-01

    Full Text Available The robust H∞ fusion filtering problem is considered for linear time-varying uncertain systems observed by multiple sensors. A performance index function for this problem is defined as an indefinite quadratic inequality which is solved by the projection method in Krein space. On this basis, a robust centralized finite horizon H∞ fusion filtering algorithm is proposed. However, this centralized fusion method is with poor real time property, as the number of sensors increases. To resolve this difficulty, within the sequential fusion framework, the performance index function is described as a set of quadratic inequalities including an indefinite quadratic inequality. And a sequential robust finite horizon H∞ fusion filtering algorithm is given by solving this quadratic inequality group. Finally, two simulation examples for time-varying/time-invariant multisensor systems are exploited to demonstrate the effectiveness of the proposed methods in the respect of the real time property and filtering accuracy.

  18. Disturbance observer based sliding mode control of nonlinear mismatched uncertain systems

    Science.gov (United States)

    Ginoya, Divyesh; Shendge, P. D.; Phadke, S. B.

    2015-09-01

    This paper presents a new design of multiple-surface sliding mode control for a class of nonlinear uncertain systems with mismatched uncertainties and disturbances. In the method of multiple-surface sliding mode control, it is required to compensate for the derivatives of the virtual inputs which gives rise to the so-called problem of 'explosion of terms'. In this paper a disturbance observer based multiple-surface sliding mode control is proposed to estimate the uncertainties as well as the derivative of the virtual inputs to overcome this problem. The practical stability of the overall system is proved. The effectiveness of the proposed control strategy is illustrated via simulation of a benchmark problem and comparison with other control strategies. The proposed scheme is validated by implementing it on a serial flexible joint manipulator in the laboratory.

  19. Robust output feedback cruise control for high-speed train movement with uncertain parameters

    Science.gov (United States)

    Li, Shu-Kai; Yang, Li-Xing; Li, Ke-Ping

    2015-01-01

    In this paper, the robust output feedback cruise control for high-speed train movement with uncertain parameters is investigated. The dynamic of a high-speed train is modeled by a cascade of cars connected by flexible couplers, which is subject to rolling mechanical resistance, aerodynamic drag and wind gust. Based on Lyapunov’s stability theory, the sufficient condition for the existence of the robust output feedback cruise control law is given in terms of linear matrix inequalities (LMIs), under which the high-speed train tracks the desired speed, the relative spring displacement between the two neighboring cars is stable at the equilibrium state, and meanwhile a small prescribed H∞ disturbance attenuation level is guaranteed. One numerical example is given to illustrate the effectiveness of the proposed methods. Project supported by the Fundamental Research Funds for the Central Universities of Ministry of Education of China (Grant No.2014JBM150).

  20. Robust Distributed Kalman Filter for Wireless Sensor Networks with Uncertain Communication Channels

    Directory of Open Access Journals (Sweden)

    Du Yong Kim

    2012-01-01

    Full Text Available We address a state estimation problem over a large-scale sensor network with uncertain communication channel. Consensus protocol is usually used to adapt a large-scale sensor network. However, when certain parts of communication channels are broken down, the accuracy performance is seriously degraded. Specifically, outliers in the channel or temporal disconnection are avoided via proposed method for the practical implementation of the distributed estimation over large-scale sensor networks. We handle this practical challenge by using adaptive channel status estimator and robust L1-norm Kalman filter in design of the processor of the individual sensor node. Then, they are incorporated into the consensus algorithm in order to achieve the robust distributed state estimation. The robust property of the proposed algorithm enables the sensor network to selectively weight sensors of normal conditions so that the filter can be practically useful.

  1. Randomized Algorithms for Analysis and Control of Uncertain Systems With Applications

    CERN Document Server

    Tempo, Roberto; Dabbene, Fabrizio

    2013-01-01

    The presence of uncertainty in a system description has always been a critical issue in control. The main objective of Randomized Algorithms for Analysis and Control of Uncertain Systems, with Applications (Second Edition) is to introduce the reader to the fundamentals of probabilistic methods in the analysis and design of systems subject to deterministic and stochastic uncertainty. The approach propounded by this text guarantees a reduction in the computational complexity of classical  control algorithms and in the conservativeness of standard robust control techniques. The second edition has been thoroughly updated to reflect recent research and new applications with chapters on statistical learning theory, sequential methods for control and the scenario approach being completely rewritten.   Features: ·         self-contained treatment explaining Monte Carlo and Las Vegas randomized algorithms from their genesis in the principles of probability theory to their use for system analysis; ·    ...

  2. Adaptive robust fault tolerant control design for a class of nonlinear uncertain MIMO systems with quantization.

    Science.gov (United States)

    Ao, Wei; Song, Yongdong; Wen, Changyun

    2017-05-01

    In this paper, we investigate the adaptive control problem for a class of nonlinear uncertain MIMO systems with actuator faults and quantization effects. Under some mild conditions, an adaptive robust fault-tolerant control is developed to compensate the affects of uncertainties, actuator failures and errors caused by quantization, and a range of the parameters for these quantizers is established. Furthermore, a Lyapunov-like approach is adopted to demonstrate that the ultimately uniformly bounded output tracking error is guaranteed by the controller, and the signals of the closed-loop system are ensured to be bounded, even in the presence of at most m-q actuators stuck or outage. Finally, numerical simulations are provided to verify and illustrate the effectiveness of the proposed adaptive schemes. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Querying Uncertain Data in Geospatial Object-relational Databases Using SQL and Fuzzy Sets

    Science.gov (United States)

    Ďuračiová, R.

    2013-12-01

    This paper deals with uncertainty modeling in spatial object-relational databases by the use of Structured Query Language (SQL). The fundamental principles of uncertainty modeling by fuzzy sets are applied in the area of geographic information systems (GIS) and spatial databases. A spatial database system includes types of spatial data and implements the spatial extension of SQL. The implementation of the principles of fuzzy logic to spatial databases brings an opportunity for the efficient processing of uncertain data, which is important, especially when using various data sources (e.g., multi-criteria decision making (MCDM) on the basis of heterogeneous spatial data resources). The modeling and data processing of uncertainties are presented in relation to the applicable International Organization for Standardization (ISO) standards (standards of the series 19100 Geographic information) and the relevant specifications of the Open Geospatial Consortium (OGC). The fuzzy spatial query approach is applied and tested on a case study with a fundamental database for GIS in Slovakia.

  4. Voluminous Incidental Oncocytic Neoplasm of the Adrenal Gland With Uncertain Malignant Potential

    Directory of Open Access Journals (Sweden)

    Marouene Chakroun

    2016-09-01

    Full Text Available A 74-year-old man presented with right flank pain and a palpable mass in the left flank. Blood pressure was normal. Contrastenhanced computed tomography (CT showed a 17 × 16 × 12 cm retroperitoneal mass over the left kidney, solid and heterogeneous. There were also 3 retro aortic lymph nodes and bilateral renal lithiasis. Twenty four-hour urinary metanephrines and normetanephrines were normal. The patient underwent a resection of the mass with left adrenalectomy by a lumbar incision. Histological findings revealed an adrenal oncocytic neoplasm (AON with uncertain malignant potential. Six months after surgery, CT control showed neither local nor distant recurrence.

  5. Finite-Time Control for Robust Tracking Consensus in MASs With an Uncertain Leader.

    Science.gov (United States)

    Lu, Xiaoqing; Wang, Yaonan; Yu, Xinghuo; Lai, Jingang

    2017-05-01

    This paper investigates the finite-time control for robust tracking consensus problems of multiagent systems with an uncertain leader for situations where the state of the considered active leader may not be measured and the directed network topology is time-varying. Based on the neighbor-based state-estimation rule and a new Lyapunov stability analysis method, a continuous and nonlinear distributed tracking protocol using only relative position information is designed, under which each agent can follow the leader in finite time if the input (acceleration) of the leader is known, and the tracking errors can converge to a bounded region in finite time if the input of the leader is unknown. In particular, a special continuous distributed tracking protocol with bounded control inputs is introduced to track the active leader in finite time. Numerical simulations are also given to illustrate the effectiveness of the theoretic results.

  6. Project Delivery System Mode Decision Based on Uncertain AHP and Fuzzy Sets

    Science.gov (United States)

    Kaishan, Liu; Huimin, Li

    2017-12-01

    The project delivery system mode determines the contract pricing type, project management mode and the risk allocation among all participants. Different project delivery system modes have different characteristics and applicable scope. For the owners, the selection of the delivery mode is the key point to decide whether the project can achieve the expected benefits, it relates to the success or failure of project construction. Under the precondition of comprehensively considering the influence factors of the delivery mode, the model of project delivery system mode decision was set up on the basis of uncertain AHP and fuzzy sets, which can well consider the uncertainty and fuzziness when conducting the index evaluation and weight confirmation, so as to rapidly and effectively identify the most suitable delivery mode according to project characteristics. The effectiveness of the model has been verified via the actual case analysis in order to provide reference for the construction project delivery system mode.

  7. Optimized ready mixed concrete truck scheduling for uncertain factors using bee algorithm

    Directory of Open Access Journals (Sweden)

    Nuntana Mayteekrieangkrai

    2015-04-01

    Full Text Available This research proposes a systematic model by using bee algorithm to optimize ready mixed concrete truck scheduling problem from a single plant to multiple sized receivers in a large search space using uncertain factors of bee algorithm compared to genetic algorithm. The objective is to minimize the total waiting durations of RMC trucks. Four benchmark problems with 3, 5, 9 and 12 construction sites are evaluated. Furthermore, eight additional problems are created from the previous four problems by varying demands and traveling durations, in order to prove the algorithm accuracy and efficiency. Hence, a total of 12 problems would be solved using both BA and GA. The simulation results show that the BA approach can get lower total waiting durations and faster than GA for all problems. This research offers a more efficient alternative for solving RMC truck scheduling.

  8. Adaptive control for time-delay teleoperation systems with uncertain dynamics

    Science.gov (United States)

    Liu, Shan; Zhang, Xia; Zheng, Wenfeng; Yang, Bo

    2017-08-01

    In most teleoperation systems, the dynamics are uncertain and the communications exhibit time delays. In order to confront these problems, this paper reports a position error-based bilateral adaptive controller, in which the unknown operator dynamical parameters and environmental dynamical parameters are included in the unknown vector of the system to be evaluated, adaptive estimate laws are compensated by estimate errors and dissipation by time delays are compensated. By using Lyapunov-Krasovskii stability theorem, it is proved that both position errors and velocities of the teleoperation system asymptotically convergent to zero. Simulations are performed to compare the performance of the proposed controller with the traditional adaptive controller and to demonstrate the efficiency of the developed teleoperation control system.

  9. Robust finite-time chaos synchronization of uncertain permanent magnet synchronous motors.

    Science.gov (United States)

    Chen, Qiang; Ren, Xuemei; Na, Jing

    2015-09-01

    In this paper, a robust finite-time chaos synchronization scheme is proposed for two uncertain third-order permanent magnet synchronous motors (PMSMs). The whole synchronization error system is divided into two cascaded subsystems: a first-order subsystem and a second-order subsystem. For the first subsystem, we design a finite-time controller based on the finite-time Lyapunov stability theory. Then, according to the backstepping idea and the adding a power integrator technique, a second finite-time controller is constructed recursively for the second subsystem. No exogenous forces are required in the controllers design but only the direct-axis (d-axis) and the quadrature-axis (q-axis) stator voltages are used as manipulated variables. Comparative simulations are provided to show the effectiveness and superior performance of the proposed method. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

  10. IMC based feedforward controller framework for disturbance attenuation on uncertain systems.

    Science.gov (United States)

    Vilanova, R; Arrieta, O; Ponsa, P

    2009-10-01

    This paper presents a generalization of the Internal Model Control (IMC) approach to feedforward control action generation. As is well known, one of the distinctive features of the IMC formulation is the possibility to distinguish between the nominal and uncertain situations. However the consideration of the presence of uncertainty for the feedforward part of the controller is not as simple as that for the feedback one. In this sense, what is proposed in this paper provides a more systematic way of addressing a robust feedforward design. In addition, being one of the major drawbacks of the Internal Model Control to have to deal with stable systems, the generalization presented here allows for unstable plants as well as unstable disturbance models.

  11. Simultaneous Robust Fault and State Estimation for Linear Discrete-Time Uncertain Systems

    Directory of Open Access Journals (Sweden)

    Feten Gannouni

    2017-01-01

    Full Text Available We consider the problem of robust simultaneous fault and state estimation for linear uncertain discrete-time systems with unknown faults which affect both the state and the observation matrices. Using transformation of the original system, a new robust proportional integral filter (RPIF having an error variance with an optimized guaranteed upper bound for any allowed uncertainty is proposed to improve robust estimation of unknown time-varying faults and to improve robustness against uncertainties. In this study, the minimization problem of the upper bound of the estimation error variance is formulated as a convex optimization problem subject to linear matrix inequalities (LMI for all admissible uncertainties. The proportional and the integral gains are optimally chosen by solving the convex optimization problem. Simulation results are given in order to illustrate the performance of the proposed filter, in particular to solve the problem of joint fault and state estimation.

  12. Aircraft Cockpit Ergonomic Layout Evaluation Based on Uncertain Linguistic Multiattribute Decision Making

    Directory of Open Access Journals (Sweden)

    Junxuan Chen

    2014-03-01

    Full Text Available In the view of the current cockpit information interaction, facilities and other characteristics are increasingly multifarious; the early layout evaluation methods based on single or partial components, often cause comprehensive evaluation unilateral, leading to the problems of long development period and low efficiency. Considering the fuzziness of ergonomic evaluation and diversity of evaluation information attributes, we refine and build an evaluation system based on the characteristics of the current cockpit man-machine layout and introduce the different types of uncertain linguistic multiple attribute combination decision making (DTULDM method in the cockpit layout evaluation process. Meanwhile, we also establish an aircraft cockpit ergonomic layout evaluation model. Finally, an experiment about cockpit layout evaluation is given, and the result demonstrates that the proposed method about cockpit ergonomic layout evaluation is feasible and effective.

  13. Primary intraosseous smooth muscle tumor of uncertain malignant potential: original report and molecular characterization

    Directory of Open Access Journals (Sweden)

    Lauren Kropp

    2016-11-01

    Full Text Available We report the first case of primary intraosseous smooth muscle tumor of uncertain malignant potential (STUMP which is analogous to borderline malignant uterine smooth muscle tumors so designated. The tumor presented in the femur of an otherwise healthy 30-year-old woman. Over a 3-year period, the patient underwent 11 biopsies or resections and 2 cytologic procedures. Multiple pathologists reviewed the histologic material including musculoskeletal pathologists but could not reach a definitive diagnosis. However, metastases eventually developed and were rapidly progressive and responsive to gemcitabine and docetaxel. Molecular characterization and ultrastructural analysis was consistent with smooth muscle origin, and amplification of unmutated chromosome 12p and 12q segments appears to be the major genomic driver of this tumor. Primary intraosseous STUMP is thought to be genetically related to leiomyosarcoma of bone, but likely representing an earlier stage of carcinogenesis. Wide excision and aggressive followup is warranted for this potentially life-threatening neoplasm.

  14. Robust optimization model and algorithm for railway freight center location problem in uncertain environment.

    Science.gov (United States)

    Liu, Xing-Cai; He, Shi-Wei; Song, Rui; Sun, Yang; Li, Hao-Dong

    2014-01-01

    Railway freight center location problem is an important issue in railway freight transport programming. This paper focuses on the railway freight center location problem in uncertain environment. Seeing that the expected value model ignores the negative influence of disadvantageous scenarios, a robust optimization model was proposed. The robust optimization model takes expected cost and deviation value of the scenarios as the objective. A cloud adaptive clonal selection algorithm (C-ACSA) was presented. It combines adaptive clonal selection algorithm with Cloud Model which can improve the convergence rate. Design of the code and progress of the algorithm were proposed. Result of the example demonstrates the model and algorithm are effective. Compared with the expected value cases, the amount of disadvantageous scenarios in robust model reduces from 163 to 21, which prove the result of robust model is more reliable.

  15. Assessing Genetic Variants of Uncertain Significance: The Example of Lynch Syndrome

    DEFF Research Database (Denmark)

    Rasmussen, Lene Juel; Heinen, Christopher D.

    2014-01-01

    A significant fraction of cancer is the result of genetic predisposition. Frequently, in patients with suspected cancer predisposition, subtle variations are found in predisposing genes. Currently, it is often not possible to determine whether such variants are pathogenic, thus they are termed...... variants of uncertain significance (VUS). This leads to anxiety in carriers and noncarrying relatives alike, as well as to an unnecessary burden to preventive healthcare. The establishment of procedures that enable the diagnostic assessment of VUSs in individuals are discussed and hereditary colorectal...... cancer syndrome, Lynch syndrome, is used as an example. This challenge is addressed by illustrating the importance of combining genetic and functional data in future strategies to assess VUS. The proposed strategies combine clinical genetic, analytical, functional and in silico approaches....

  16. An Active Fault-Tolerant Control Method Ofunmanned Underwater Vehicles with Continuous and Uncertain Faults

    Directory of Open Access Journals (Sweden)

    Daqi Zhu

    2008-11-01

    Full Text Available This paper introduces a novel thruster fault diagnosis and accommodation system for open-frame underwater vehicles with abrupt faults. The proposed system consists of two subsystems: a fault diagnosis subsystem and a fault accommodation sub-system. In the fault diagnosis subsystem a ICMAC(Improved Credit Assignment Cerebellar Model Articulation Controllers neural network is used to realize the on-line fault identification and the weighting matrix computation. The fault accommodation subsystem uses a control algorithm based on weighted pseudo-inverse to find the solution of the control allocation problem. To illustrate the proposed method effective, simulation example, under multi-uncertain abrupt faults, is given in the paper.

  17. Adaptive Robust Actuator Fault Accommodation for a Class of Uncertain Nonlinear Systems with Unknown Control Gains

    Directory of Open Access Journals (Sweden)

    Yuefei Wu

    2014-01-01

    Full Text Available An adaptive robust fault tolerant control approach is proposed for a class of uncertain nonlinear systems with unknown signs of high-frequency gain and unmeasured states. In the recursive design, neural networks are employed to approximate the unknown nonlinear functions, K-filters are designed to estimate the unmeasured states, and a dynamical signal and Nussbaum gain functions are introduced to handle the unknown sign of the virtual control direction. By incorporating the switching function σ algorithm, the adaptive backstepping scheme developed in this paper does not require the real value of the actuator failure. It is mathematically proved that the proposed adaptive robust fault tolerant control approach can guarantee that all the signals of the closed-loop system are bounded, and the output converges to a small neighborhood of the origin. The effectiveness of the proposed approach is illustrated by the simulation examples.

  18. Distributed Secondary Voltage and Frequency Control for Islanded Microgrids with Uncertain Communication Links

    DEFF Research Database (Denmark)

    Lu, Xiaoqing; Yu, Xinghuo; Lai, Jingang

    2017-01-01

    This paper presents a robust distributed secondary control (DSC) scheme for inverter-based microgrids (MGs) in a distribution sparse network with uncertain communication links. By using the iterative learning mechanics, two discrete-time DSC controllers are designed, which enable all distributed...... intermittently in a low-bandwidth communication manner. This way, the communication costs are greatly reduced, and some sufficient conditions on the system stability and robustness to the uncertainties are also derived by using the tools of Lyapunov stability theory, algebraic graph theory, and matrix inequality...... theory. The proposed controllers are implemented on local DERs, and thus no central controller is required. Moreover, the desired control objective can also be guaranteed even if all DERs are subject to internal uncertainties and external noises including initial voltage and/or frequency resetting errors...

  19. Guaranteed estimation of solutions to Helmholtz transmission problems with uncertain data from their indirect noisy observations

    Science.gov (United States)

    Podlipenko, Yu. K.; Shestopalov, Yu. V.

    2017-09-01

    We investigate the guaranteed estimation problem of linear functionals from solutions to transmission problems for the Helmholtz equation with inexact data. The right-hand sides of equations entering the statements of transmission problems and the statistical characteristics of observation errors are supposed to be unknown and belonging to certain sets. It is shown that the optimal linear mean square estimates of the above mentioned functionals and estimation errors are expressed via solutions to the systems of transmission problems of the special type. The results and techniques can be applied in the analysis and estimation of solution to forward and inverse electromagnetic and acoustic problems with uncertain data that arise in mathematical models of the wave diffraction on transparent bodies.

  20. A fuzzy pert approach to evaluate plant construction project scheduling risk under uncertain resources capacity

    Directory of Open Access Journals (Sweden)

    Hsian Jong Hsiau

    2009-07-01

    Full Text Available A plant construction project always involves lots of activities. Precise information about the activities duration is unfortunately unavailable due to the uncertain resources capacity. The fuzzy program evaluation and review technique (PERT has been widely applied to solve the fuzzy project scheduling problem. This paper presents an extended fuzzy PERT approach with four major improvement aspects to support the construction project scheduling management: 1 Evaluate operation fuzzy times based on available working volumes, resources quantity and fuzzy capacity of resources, 2 Adopting a maximal alpha_i-level cut method to compare the fuzzy precedent activities times to determine the reasonable earliest starting times of each activity, 3 Using fuzzy algebra method instead of fuzzy subtraction method to compute the fuzzy latest starting times and 4 Developing a project scheduling risk index (PSRI to assist the decision maker to evaluate the project scheduling risk. Simulations experiments are conducted and demonstrated satisfactory results.

  1. Variational Assimilation of Sparse and Uncertain Satellite Data For 1D Saint-Venant River Models

    Science.gov (United States)

    Garambois, P. A.; Brisset, P.; Monnier, J.; Roux, H.

    2016-12-01

    Profusion of satellites are providing increasingly accurate measurements of continental water cyle, and water bodies variations while in situ observability is declining. The future Surface Water and Ocean Topography (SWOT) mission will provide maps of river surface elevations widths and slopes with an almost global coverage and temporal revisits. This will offer the possibility to address a larger variety of inverse problems in surface hydrology. Data assimilation techniques, that are broadly used in several scientific fields, aim to optimally combine models, system observations and prior information. Variational assimilation consists in iterative minimization of a discrepency measure between model outputs and observations, here for retrieving boundary conditions and parameters of a 1D Saint Venant model. Nevertheless, inferring river discharge and hydraulic parameters thanks to the observation of river surface is not straightforward. This is particularly true in the case of sparse and uncertain observations of flow state variables since they are governed by nonlinear physical processes. This paper investigates the identifiability of hydraulic controls given sparse and uncertain satellite observations of a river. The identifiability of river discharge alone and with roughness is tested for several spatio temporal patterns of river observations, including SWOT like observations. A new 1D Shallow water model with variational data assimilation, within the DassFlow chain is presented as well as postprocessing and observation operator dedicated to the future SWOT and SWOT simulator data. In view to decrease inverse problem dimensionality discharge is represented in a reduced basis. Moreover we introduce an original and reduced parametrization of the flow resistance that can account for various flow regimes along with a cross section design dedicated to remote sensing. We show which discharge temporal frequencies can be identified w.r.t observation ones and at which

  2. Minimizing the regrets of long-term urban floodplain management decisions under deeply uncertain climate change

    Science.gov (United States)

    Hecht, J. S.; Kirshen, P. H.; Vogel, R. M.

    2016-12-01

    Making long-term floodplain management decisions under uncertain climate change is a major urban planning challenge of the 21stcentury. To support these efforts, we introduce a screening-level optimization model that identifies adaptation portfolios by minimizing the regrets associated with their flood-control and damage costs under different climate change trajectories that are deeply uncertain, i.e. have probabilities that cannot be specified plausibly. This mixed integer program explicitly considers the coupled damage-reduction impacts of different floodwall designs and property-scale investments (first-floor elevation, wet floodproofing of basements, permanent retreat and insurance), recommends implementation schedules, and assesses impacts to stakeholders residing in three types of homes. An application to a stylized municipality illuminates many nonlinear system dynamics stemming from large fixed capital costs, infrastructure design thresholds, and discharge-depth-damage relationships. If stakeholders tolerate mild damage, floodwalls that fully protect a community from large design events are less cost-effective than portfolios featuring both smaller floodwalls and property-scale measures. Potential losses of property tax revenue from permanent retreat motivate municipal property-tax initiatives for adaptation financing. Yet, insurance incentives for first-floor elevation may discourage locally financed floodwalls, in turn making lower-income residents more vulnerable to severe flooding. A budget constraint analysis underscores the benefits of flexible floodwall designs with low incremental expansion costs while near-optimal solutions demonstrate the scheduling flexibility of many property-scale measures. Finally, an equity analysis shows the importance of evaluating the overpayment and under-design regrets of recommended adaptation portfolios for each stakeholder and contrasts them to single-scenario model results.

  3. Chronic kidney diseases of uncertain etiology (CKDue) in Sri Lanka: geographic distribution and environmental implications.

    Science.gov (United States)

    Chandrajith, Rohana; Nanayakkara, Shanika; Itai, Kozuyoshi; Aturaliya, T N C; Dissanayake, C B; Abeysekera, Thilak; Harada, Kouji; Watanabe, Takao; Koizumi, Akio

    2011-06-01

    The increase in the number of chronic kidney disease (CKD) patients from the north central region of Sri Lanka has become a environmental health issue of national concern. Unlike in other countries where long-standing diabetes and hypertension are the leading causes of renal diseases, the majority of CKD patients from this part of Sri Lanka do not show any identifiable cause. As the disease is restricted to a remarkably specific geographical terrain, particularly in the north central dry zone of the country, multidisciplinary in-depth research studies are required to identify possible etiologies and risk factors. During this study, population screening in the prevalent region and outside the region, analysis of geoenvironmental and biochemical samples were carried out. Population screening that was carried out using a multistage sampling technique indicated that the point prevalence of CKD with uncertain etiology is about 2-3% among those above 18 years of age. Drinking water collected from high-prevalent and non-endemic regions was analyzed for their trace and ultratrace element contents, including the nephrotoxic heavy metals Cd and U using ICP-MS. The results indicate that the affected regions contain moderate to high levels of fluoride. The Cd contents in drinking water, rice from affected regions and urine from symptomatic and non-symptomatic patients were much lower indicating that Cd is not a contributing factor for CKD with uncertain etiology in Sri Lanka. Although no single geochemical parameter could be clearly and directly related to the CKD etiology on the basis of the elements determined during this study, it is very likely that the unique hydrogeochemistry of the drinking water is closely associated with the incidence of the disease. © Springer Science+Business Media B.V. 2010

  4. Incorporating Deeply Uncertain Factors into the Many Objective Search Process: Improving Adaptation to Environmental Change

    Science.gov (United States)

    Kasprzyk, J. R.; Watson, A. A.

    2014-12-01

    Deep uncertainty refers to situations in which decision makers or stakeholders do not know, or cannot fully agree upon, the full suite of risk factors within a planning problem. This phenomenon is especially important when considering scenarios of future environmental change, since there exist multiple trajectories of environmental forcings (e.g., streamflow timing and magnitude) and socioeconomic factors (e.g., population growth). This presentation first briefly reviews robust optimization and scenario approaches that have been proposed to plan for systems under deep uncertainty. One recently introduced framework is Many Objective Robust Decision Making (MORDM). MORDM combines two techniques: evolutionary algorithm search is used to generate planning alternatives, and robust decision making methods are used to sample performance over a large range of plausible factors and, subsequently, choose a robust solution. Within MORDM, Pareto approximate tradeoff sets of solutions are used to balance objectives and examine alternatives. However, MORDM does not currently incorporate the deeply uncertain scenario information into the search process itself. In this presentation, we suggest several avenues for doing so, that are focused on modifying the suite of uncertain data that is selected within the search process. Visualizations that compare tradeoff sets across different sets of assumptions can be used to guide decision makers' learning and, ultimately, their selection of several candidate solutions for further planning. For example, the baseline assumptions about probability distributions can be compared to optimization results under severe events to determine adaptive management strategies. A case study of water planning in the Lower Rio Grande Valley (LRGV) in Texas is used to demonstrate the approach. Our LRGV results compare baseline optimization with new solution sets that examine optimal management strategies under scenarios characterized by lower than average

  5. Continuous neural identifier for uncertain nonlinear systems with time delays in the input signal.

    Science.gov (United States)

    Alfaro-Ponce, M; Argüelles, A; Chairez, I

    2014-12-01

    Time-delay systems have been successfully used to represent the complexity of some dynamic systems. Time-delay is often used for modeling many real systems. Among others, biological and chemical plants have been described using time-delay terms with better results than those models that have not consider them. However, getting those models represented a challenge and sometimes the results were not so satisfactory. Non-parametric modeling offered an alternative to obtain suitable and usable models. Continuous neural networks (CNN) have been considered as a real alternative to provide models over uncertain non-parametric systems. This article introduces the design of a specific class of non-parametric model for uncertain time-delay system based on CNN considering the so-called delayed learning laws analysis. The convergence analysis as well as the learning laws were produced by means of a Lyapunov-Krasovskii functional. Three examples were developed to demonstrate the effectiveness of the modeling process forced by the identifier proposed in this study. The first example was a simple nonlinear model used as benchmark example. The second example regarded the human immunodeficiency virus dynamic behavior is used to show the performance of the suggested non-parametric identifier based on CNN for no fictitious neither academic models. Finally, a third example describing the evolution of hepatitis B virus served to test the identifier presented in this study and was also useful to provide evidence of its superior performance against a non-delayed identifier based on CNN. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Antenatal genetic testing and the right to remain in ignorance.

    Science.gov (United States)

    Bennett, R

    2001-09-01

    As knowledge increases about the human genome, prenatal genetic testing will become cheaper, safer and more comprehensive. It is likely that there will be a great deal of support for making prenatal testing for a wide range of genetic disorders a routine part of antenatal care. Such routine testing is necessarily coercive in nature and does not involve the same standard of consent as is required in other health care settings. This paper asks whether this level of coercion is ethically justifiable in this case, or whether pregnant women have a right to remain in ignorance of the genetic make-up of the fetus they are carrying. While information gained by genetic testing may be useful for pregnant women when making decisions about their pregnancy, it does not prevent harm to future children. It is argued that as this kind of testing provides information in the interests of the pregnant women and not in the interests of any future child, the same standards of consent that are normally required for genetic testing should be required in this instance.

  7. Prions adhere to soil minerals and remain infectious.

    Directory of Open Access Journals (Sweden)

    Christopher J Johnson

    2006-04-01

    Full Text Available An unidentified environmental reservoir of infectivity contributes to the natural transmission of prion diseases (transmissible spongiform encephalopathies [TSEs] in sheep, deer, and elk. Prion infectivity may enter soil environments via shedding from diseased animals and decomposition of infected carcasses. Burial of TSE-infected cattle, sheep, and deer as a means of disposal has resulted in unintentional introduction of prions into subsurface environments. We examined the potential for soil to serve as a TSE reservoir by studying the interaction of the disease-associated prion protein (PrP(Sc with common soil minerals. In this study, we demonstrated substantial PrP(Sc adsorption to two clay minerals, quartz, and four whole soil samples. We quantified the PrP(Sc-binding capacities of each mineral. Furthermore, we observed that PrP(Sc desorbed from montmorillonite clay was cleaved at an N-terminal site and the interaction between PrP(Sc and Mte was strong, making desorption of the protein difficult. Despite cleavage and avid binding, PrP(Sc bound to Mte remained infectious. Results from our study suggest that PrP(Sc released into soil environments may be preserved in a bioavailable form, perpetuating prion disease epizootics and exposing other species to the infectious agent.

  8. Factors influencing home care nurse intention to remain employed.

    Science.gov (United States)

    Tourangeau, Ann; Patterson, Erin; Rowe, Alissa; Saari, Margaret; Thomson, Heather; MacDonald, Geraldine; Cranley, Lisa; Squires, Mae

    2014-11-01

    To identify factors affecting Canadian home care nurse intention to remain employed (ITR). In developed nations, healthcare continues to shift into community settings. Although considerable research exists on examining nurse ITR in hospitals, similar research related to nurses employed in home care is limited. In the face of a global nursing shortage, it is important to understand the factors influencing nurse ITR across healthcare sectors. A qualitative exploratory descriptive design was used. Focus groups were conducted with home care nurses. Data were analysed using qualitative content analysis. Six categories of influencing factors were identified by home care nurses as affecting ITR: job characteristics; work structures; relationships/communication; work environment; nurse responses to work; and employment conditions. Findings suggest the following factors influence home care nurse ITR: having autonomy; flexible scheduling; reasonable and varied workloads; supportive work relationships; and receiving adequate pay and benefits. Home care nurses did not identify job satisfaction as a single concept influencing ITR. Home care nursing management should support nurse autonomy, allow flexible scheduling, promote reasonable workloads and create opportunities for team building that strengthen supportive relationships among home care nurses and other health team members. © 2013 John Wiley & Sons Ltd.

  9. [Bacterial vaginosis in 2011: a lot of questions remain].

    Science.gov (United States)

    Bohbot, J-M; Lepargneur, J-P

    2012-01-01

    Bacterial vaginosis is one of the most frequent vaginal affections. It results from a deep imbalance of the vaginal ecosystem whose mechanisms remain mysterious, even if recent progress were accomplished in their comprehension: if the flora implied in the bacterial vaginosis is recognized like polymorphic, it appears that Gardnerella vaginalis plays a major part with two genomically different forms: a commensal form (slightly adhesive to the epithelial cells), and a pathogenic one (strongly adhesive to the epithelial cells); the changes in lactobacilli are also to take into account: L. iners could be a marker of the vaginal flora imbalance whereas L. crispatus is generally met in the normal vaginal flora. These findings could influence the composition of coming probiotics; it is recognized that bacterial vaginosis is involved in the risk of prematurity but molecular quantification of G. vaginalis (and of Atopobium vaginae) is more sensitive for the diagnosis of BV what could improve the detection of high-risk pregnant women. The isolated antibiotic treatments are not very effective on the prevention of recurrences. The rebalancing of the vaginal flora is essential. In this field, the local estrogens showed some effectiveness. The use of probiotics is promising and can be recommended in complement of the antibiotic treatment even if the results of the clinical studies are still too heterogeneous to lead to precise indications. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  10. Anion exchange membrane fuel cells: Current status and remaining challenges

    Science.gov (United States)

    Gottesfeld, Shimshon; Dekel, Dario R.; Page, Miles; Bae, Chulsung; Yan, Yushan; Zelenay, Piotr; Kim, Yu Seung

    2018-01-01

    The anion exchange membrane fuel cell (AEMFC) is an attractive alternative to acidic proton exchange membrane fuel cells, which to date have required platinum-based catalysts, as well as acid-tolerant stack hardware. The AEMFC could use non-platinum-group metal catalysts and less expensive metal hardware thanks to the high pH of the electrolyte. Over the last decade, substantial progress has been made in improving the performance and durability of the AEMFC through the development of new materials and the optimization of system design and operation conditions. In this perspective article, we describe the current status of AEMFCs as having reached beginning of life performance very close to that of PEMFCs when using ultra-low loadings of Pt, while advancing towards operation on non-platinum-group metal catalysts alone. In the latter sections, we identify the remaining technical challenges, which require further research and development, focusing on the materials and operational factors that critically impact AEMFC performance and/or durability. These perspectives may provide useful insights for the development of next-generation of AEMFCs.

  11. Barrett's esophagus-related diseases remain uncommon in China.

    Science.gov (United States)

    Huang, Qin; Fang, Dian Chun; Yu, Cheng Gong; Zhang, Jun; Chen, Min Hu

    2011-12-01

    Barrett's esophagus (BE)-related esophageal adenocarcinoma (EAC) has shown the fastest rise in incidence in Western countries; however, research data on BE-related diseases from China are inconclusive. We aimed to review and analyze the published results on these diseases in China. We searched PubMed and Chinese medical literature for key words: BE, EAC, Chinese and China. Relevant research papers along with the study results from our own groups were reviewed and analyzed. Using standardized criteria, columnar-lined esophagus (CLE) was found in as many as 29% of resection specimens in Chinese patients with proximal gastric cancer. However, BE with intestinal metaplasia was rare, ranging from 0.06% in the general population to disease and tobacco or alcohol abuse, but not male gender or obesity. At endoscopy, most CLE/BE were diseases, except for CLE, are rare in China. The clinical significance and malignant potential of CLE in the Chinese population remain elusive. Further investigation on these diseases is in progress. © 2011 The Authors. Journal of Digestive Diseases © 2011 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and Blackwell Publishing Asia Pty Ltd.

  12. New Evidence Links Stellar Remains to Oldest Recorded Supernova

    Science.gov (United States)

    2006-09-01

    Recent observations have uncovered evidence that helps to confirm the identification of the remains of one of the earliest stellar explosions recorded by humans. The new study shows that the supernova remnant RCW 86 is much younger than previously thought. As such, the formation of the remnant appears to coincide with a supernova observed by Chinese astronomers in 185 A.D. The study used data from NASA's Chandra X-ray Observatory and the European Space Agency's XMM-Newton Observatory, "There have been previous suggestions that RCW 86 is the remains of the supernova from 185 A.D.," said Jacco Vink of University of Utrecht, the Netherlands, and lead author of the study. "These new X-ray data greatly strengthen the case." When a massive star runs out of fuel, it collapses on itself, creating a supernova that can outshine an entire galaxy. The intense explosion hurls the outer layers of the star into space and produces powerful shock waves. The remains of the star and the material it encounters are heated to millions of degrees and can emit intense X-ray radiation for thousands of years. Animation of a Massive Star Explosion Animation of a Massive Star Explosion In their stellar forensic work, Vink and colleagues studied the debris in RCW 86 to estimate when its progenitor star originally exploded. They calculated how quickly the shocked, or energized, shell is moving in RCW 86, by studying one part of the remnant. They combined this expansion velocity with the size of the remnant and a basic understanding of how supernovas expand to estimate the age of RCW 86. "Our new calculations tell us the remnant is about 2,000 years old," said Aya Bamba, a coauthor from the Institute of Physical and Chemical Research (RIKEN), Japan. "Previously astronomers had estimated an age of 10,000 years." The younger age for RCW 86 may explain an astronomical event observed almost 2000 years ago. In 185 AD, Chinese astronomers (and possibly the Romans) recorded the appearance of a new

  13. Cohesin Can Remain Associated with Chromosomes during DNA Replication

    Directory of Open Access Journals (Sweden)

    James D.P. Rhodes

    2017-09-01

    Full Text Available To ensure disjunction to opposite poles during anaphase, sister chromatids must be held together following DNA replication. This is mediated by cohesin, which is thought to entrap sister DNAs inside a tripartite ring composed of its Smc and kleisin (Scc1 subunits. How such structures are created during S phase is poorly understood, in particular whether they are derived from complexes that had entrapped DNAs prior to replication. To address this, we used selective photobleaching to determine whether cohesin associated with chromatin in G1 persists in situ after replication. We developed a non-fluorescent HaloTag ligand to discriminate the fluorescence recovery signal from labeling of newly synthesized Halo-tagged Scc1 protein (pulse-chase or pcFRAP. In cells where cohesin turnover is inactivated by deletion of WAPL, Scc1 can remain associated with chromatin throughout S phase. These findings suggest that cohesion might be generated by cohesin that is already bound to un-replicated DNA.

  14. Cohesin Can Remain Associated with Chromosomes during DNA Replication.

    Science.gov (United States)

    Rhodes, James D P; Haarhuis, Judith H I; Grimm, Jonathan B; Rowland, Benjamin D; Lavis, Luke D; Nasmyth, Kim A

    2017-09-19

    To ensure disjunction to opposite poles during anaphase, sister chromatids must be held together following DNA replication. This is mediated by cohesin, which is thought to entrap sister DNAs inside a tripartite ring composed of its Smc and kleisin (Scc1) subunits. How such structures are created during S phase is poorly understood, in particular whether they are derived from complexes that had entrapped DNAs prior to replication. To address this, we used selective photobleaching to determine whether cohesin associated with chromatin in G1 persists in situ after replication. We developed a non-fluorescent HaloTag ligand to discriminate the fluorescence recovery signal from labeling of newly synthesized Halo-tagged Scc1 protein (pulse-chase or pcFRAP). In cells where cohesin turnover is inactivated by deletion of WAPL, Scc1 can remain associated with chromatin throughout S phase. These findings suggest that cohesion might be generated by cohesin that is already bound to un-replicated DNA. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  15. Remaining lifetime modeling using State-of-Health estimation

    Science.gov (United States)

    Beganovic, Nejra; Söffker, Dirk

    2017-08-01

    Technical systems and system's components undergo gradual degradation over time. Continuous degradation occurred in system is reflected in decreased system's reliability and unavoidably lead to a system failure. Therefore, continuous evaluation of State-of-Health (SoH) is inevitable to provide at least predefined lifetime of the system defined by manufacturer, or even better, to extend the lifetime given by manufacturer. However, precondition for lifetime extension is accurate estimation of SoH as well as the estimation and prediction of Remaining Useful Lifetime (RUL). For this purpose, lifetime models describing the relation between system/component degradation and consumed lifetime have to be established. In this contribution modeling and selection of suitable lifetime models from database based on current SoH conditions are discussed. Main contribution of this paper is the development of new modeling strategies capable to describe complex relations between measurable system variables, related system degradation, and RUL. Two approaches with accompanying advantages and disadvantages are introduced and compared. Both approaches are capable to model stochastic aging processes of a system by simultaneous adaption of RUL models to current SoH. The first approach requires a priori knowledge about aging processes in the system and accurate estimation of SoH. An estimation of SoH here is conditioned by tracking actual accumulated damage into the system, so that particular model parameters are defined according to a priori known assumptions about system's aging. Prediction accuracy in this case is highly dependent on accurate estimation of SoH but includes high number of degrees of freedom. The second approach in this contribution does not require a priori knowledge about system's aging as particular model parameters are defined in accordance to multi-objective optimization procedure. Prediction accuracy of this model does not highly depend on estimated SoH. This model

  16. Mineralized remains of morphotypes of filamentous cyanobacteria in carbonaceous meteorites

    Science.gov (United States)

    Hoover, Richard B.

    2005-09-01

    rocks, living, cryopreserved and fossilized extremophiles and cyanobacteria. These studies have resulted in the detection of mineralized remains of morphotypes of filamentous cyanobacteria, mats and consortia in many carbonaceous meteorites. These well-preserved and embedded microfossils are consistent with the size, morphology and ultra-microstructure of filamentous trichomic prokaryotes and degraded remains of microfibrils of cyanobacterial sheaths. EDAX elemental studies reveal that the forms in the meteorites often have highly carbonized sheaths in close association with permineralized filaments, trichomes, and microbial cells. The eextensive protocols and methodologies that have been developed to protect the samples from contamination and to distinguish recent contaminants from indigenous microfossils are described recent bio-contaminants. Ratios of critical bioelements (C:O, C:N, C:P, and C:S) reveal dramatic differences between microfossils in Earth rocks and meteorites and in the cells, filaments, trichomes, and hormogonia of recently living cyanobacteria. The results of comparative optical, ESEM and FESEM studies and EDAX elemental analyses of recent cyanobacteria (e.g. Calothrix, Oscillatoria, and Lyngbya) of similar size, morphology and microstructure to microfossils found embedded in the Murchison CM2 and the Orgueil CI1 carbonaceous meteorites are presented

  17. Genetic differences in transcript responses to low-dose ionizing radiation identify tissue functions associated with breast cancer susceptibility.

    Directory of Open Access Journals (Sweden)

    Antoine M Snijders

    Full Text Available High dose ionizing radiation (IR is a well-known risk factor for breast cancer but the health effects after low-dose (LD, <10 cGy exposures remain highly uncertain. We explored a systems approach that compared LD-induced chromosome damage and transcriptional responses in strains of mice with genetic differences in their sensitivity to radiation-induced mammary cancer (BALB/c and C57BL/6 for the purpose of identifying mechanisms of mammary cancer susceptibility. Unirradiated mammary and blood tissues of these strains differed significantly in baseline expressions of DNA repair, tumor suppressor, and stress response genes. LD exposures of 7.5 cGy (weekly for 4 weeks did not induce detectable genomic instability in either strain. However, the mammary glands of the sensitive strain but not the resistant strain showed early transcriptional responses involving: (a diminished immune response, (b increased cellular stress, (c altered TGFβ-signaling, and (d inappropriate expression of developmental genes. One month after LD exposure, the two strains showed opposing responses in transcriptional signatures linked to proliferation, senescence, and microenvironment functions. We also discovered a pre-exposure expression signature in both blood and mammary tissues that is predictive for poor survival among human cancer patients (p = 0.0001, and a post-LD-exposure signature also predictive for poor patient survival (p<0.0001. There is concordant direction of expression in the LD-exposed sensitive mouse strain, in biomarkers of human DCIS and in biomarkers of human breast tumors. Our findings support the hypothesis that genetic mechanisms that determine susceptibility to LD radiation induced mammary cancer in mice are similar to the tissue mechanisms that determine poor-survival in breast cancer patients. We observed non-linearity of the LD responses providing molecular evidence against the LNT risk model and obtained new evidence that LD responses are

  18. Multiple paths towards reduced membrane potential and concomitant reduction in aminoglycoside susceptibility in staphylococcus aureus

    DEFF Research Database (Denmark)

    Vestergaard, Martin; Nøhr-Meldgaard, Katrine; Ingmer, Hanne

    2018-01-01

    the susceptibility towards antibiotics. The aim of this study was to identify genetic determinants that upon inactivation reduce aminoglycoside susceptibility in Staphylococcus aureus. We screened the Nebraska Transposon Mutant Library of 1920 single-gene inactivations in S. aureus strain JE2, for reduced...... susceptibility to gentamicin. 9 mutants were confirmed by E-test to display between 2 and 16-fold reduced susceptibility to this antibiotic. All of the identified genes were associated with the electron transport chain and energy metabolism. Four mutant strains (menD, hemB, aroC and SAUSA300_0355) conferred...... the largest increase in gentamicin susceptibility and exhibited a small colony variant phenotype, whereas the remaining mutants (qoxA, qoxB, qoxC, ndh and hemX) displayed colony morphology similar to the wild type. All of the mutants, except hemX, displayed reduced membrane potential suggesting that reduced...

  19. Sky-view factor visualization for detection of archaeological remains

    Science.gov (United States)

    Kokalj, Žiga; Oštir, Krištof; Zakšek, Klemen

    2013-04-01

    Many archaeological remains are covered by sand or vegetation but it still possible to detect them by remote sensing techniques. One of them is airborne laser scanning that enables production of digital elevation models (DEM) of very high resolution (better than 1 m) with high relative elevation accuracy (centimetre level), even under forest. Thus, it has become well established in archaeological applications. However, effective interpretation of digital elevation models requires appropriate data visualization. Analytical relief shading is used in most cases. Although widely accepted, this method has two major drawbacks: identifying details in deep shades and inability to properly represent linear features lying parallel to the light beam. Several authors have tried to overcome these limitations by changing the position of the light source or by filtering. This contribution addresses the DEM visualization problem by sky-view factor, a visualization technique based on diffuse light that overcomes the directional problems of hill-shading. Sky-view factor is a parameter that describes the portion of visible sky limited by relief. It can be used as a general relief visualization technique to show relief characteristics. In particular, we show that this visualization is a very useful tool in archaeology. Applying the sky-view factor for visualization purposes gives advantages over other techniques because it reveals small (or large, depending on the scale of the observed phenomenon and consequential algorithm settings) relief features while preserving the perception of general topography. In the case study (DEM visualization of a fortified enclosure of Tonovcov grad in Slovenia) we show that for the archaeological purposes the sky-view factor is the optimal DEM visualization method. Its ability to consider the neighborhood context makes it an outstanding tool when compared to other visualization techniques. One can choose a large search radius and the most important

  20. Susceptibility to varicella zoster virus infection in health care workers.

    LENUS (Irish Health Repository)

    Gallagher, J

    2012-02-03

    Varicella zoster virus (VZV) is an occupational hazard for a percentage of health care staff. Nine hundred and seventy staff members attending the Occupational Health Department at Cork University Hospital took part in the survey. A latex agglutination assay was used to determine the health care workers immune status to VZV. Of the 970 workers tested, 928 (95.7%) were immune to VZV. The sensitivity, specificity and predictive value of an enquiry regarding a history of chicken-pox was determined on a sample of 206 health care workers. The positive predictive value was 95% (119\\/125) and the negative predictive value was 11% (4\\/35). The sensitivity of the enquiry was 79% (119\\/150), the specificity was 40% (4\\/10), reducing to 61% (119\\/195) and 36% (4\\/11) respectively when individuals with uncertain histories were included in the calculations. The advantages and disadvantages of selective staff screening are discussed. In the authors\\' opinion all health care workers involved in the clinical care of patients should be screened by serology for past VZV infection before taking up duty and those who are susceptible to VZV should be made aware of the risks and health effects associated with VZV if contracted.

  1. Candida and candidaemia. Susceptibility and epidemiology.

    Science.gov (United States)

    Arendrup, Maiken Cavling

    2013-11-01

    significant proportion of the patients initially received inappropriate antifungal treatment and that the outcome was significantly improved when patients with C. glabrata received caspofungin as their first line agent. This has today been incorporated in the Danish and international treatment guidelines. The prevalence of acquired antifungal resistance remained very low throughout the study period, however, we may only have detected the tip of the resistance iceberg due to the study design, where for epidemiological purposes only the initial isolate was included with the lowest antifungal exposure, and as the susceptibility tests and breakpoints were not optimal for the detection of resistance at all centres. Most Danish laboratories either do not susceptibility test or use commercial tests such as the Etest and later the VITEK system. These are FDA approved with the CLSI breakpoints which, as we have shown, have been far too high to reliably detect resistance and which despite having now been revised and harmonised are not yet in formal CLSI print and hence not incorporated in the product inserts for the commercial tests on the market. Finally, even for laboratories aware of these issues challenges are still ahead as the official breakpoints not always lead to a correct classification for MIC endpoints obtained using the commercial systems or as the commercial tests do not include a relevant concentration range for all drug bug combinations. I thus believe, the studies included in this thesis have contributed significantly to the understanding of the interplay between the Candida virulence, epidemiology and susceptibility and the importance of appropriate diagnostics and treatment choice. It is my hope that we thereby have contributed to the improved options and outcome for patients with candidaemia.

  2. BSAC standardized disc susceptibility testing method (version 10).

    Science.gov (United States)

    Andrews, J M; Howe, R A

    2011-12-01

    The BSAC standardized disc susceptibility testing method remains unchanged, but there are considerable changes to the interpretative criteria due to continuing harmonization with the European Committee on Antimicrobial Susceptibility Testing (EUCAST) MIC breakpoints. There are a number of agents for which interpretative criteria have been removed. These MIC and/or zone diameter breakpoints will be published on the BSAC web site as a 'Legacy' table; they may be used for research or comparative purposes, but are not recommended for clinical management. Notably, testing of staphylococci for susceptibility to glycopeptides by disc diffusion has been removed because this method has been found to be unreliable, particularly for the detection of low-level resistance; low-level vancomycin resistance in staphylococci is increasingly deemed to be of clinical relevance. The tables for anaerobes have been expanded to include MIC breakpoints that have been determined by EUCAST. There are currently no zone diameter breakpoints for these organisms and an MIC method is recommended if susceptibility testing is required.

  3. A Novel Scheme Adaptive Hybrid Dislocated Synchronization for Two Identical and Different Memristor Chaotic Oscillator Systems with Uncertain Parameters

    Directory of Open Access Journals (Sweden)

    Jie Chen

    2014-01-01

    Full Text Available The drive system can synchronize with the response system by the scaling factor in the traditional projective synchronization. This paper proposes a novel adaptive hybrid dislocated synchronization with uncertain parameters scheme for chaos synchronization using the Lyapunov stability theory. The drive system is synchronized by the sum of hybrid dislocated state variables for the response system. By designing effective hybrid dislocated adaptive controller and hybrid dislocated adaptive law of the parameters estimation, we investigate the synchronization of two identical memristor chaotic oscillator systems and two different memristor chaotic oscillator systems with uncertain parameters. Finally, the numerical simulation examples are provided to show the effectiveness of our method.

  4. Could MRI Be Used To Image Kidney Fibrosis? A Review of Recent Advances and Remaining Barriers.

    Science.gov (United States)

    Leung, General; Kirpalani, Anish; Szeto, Stephen G; Deeb, Maya; Foltz, Warren; Simmons, Craig A; Yuen, Darren A

    2017-06-07

    A key contributor to the progression of nearly all forms of CKD is fibrosis, a largely irreversible process that drives further kidney injury. Despite its importance, clinicians currently have no means of noninvasively assessing renal scar, and thus have historically relied on percutaneous renal biopsy to assess fibrotic burden. Although helpful in the initial diagnostic assessment, renal biopsy remains an imperfect test for fibrosis measurement, limited not only by its invasiveness, but also, because of the small amounts of tissue analyzed, its susceptibility to sampling bias. These concerns have limited not only the prognostic utility of biopsy analysis and its ability to guide therapeutic decisions, but also the clinical translation of experimental antifibrotic agents. Recent advances in imaging technology have raised the exciting possibility of magnetic resonance imaging (MRI)-based renal scar analysis, by capitalizing on the differing physical features of fibrotic and nonfibrotic tissue. In this review, we describe two key fibrosis-induced pathologic changes (capillary loss and kidney stiffening) that can be imaged by MRI techniques, and the potential for these new MRI-based technologies to noninvasively image renal scar. Copyright © 2017 by the American Society of Nephrology.

  5. Gene-wide analysis detects two new susceptibility genes for Alzheimer's disease

    OpenAIRE

    Escott-Price, Valentina; Bellenguez, Céline; Wang, Li-San; Choi, Seung-Hoan; Harold, Denise; Jones, Lesley; Holmans, Peter; Gerrish, Amy; Vedernikov, Alexey; Richards, Alexander; DeStefano, Anita L.; Lambert, Jean-Charles; Ibrahim-Verbaas, Carla A.; Naj, Adam C.; Sims, Rebecca

    2014-01-01

    PUBLISHED BACKGROUND: Alzheimer's disease is a common debilitating dementia with known heritability, for which 20 late onset susceptibility loci have been identified, but more remain to be discovered. This study sought to identify new susceptibility genes, using an alternative gene-wide analytical approach which tests for patterns of association within genes, in the powerful genome-wide association dataset of the International Genomics of Alzheimer's Project Consortium, comprising over...

  6. Multidetector CT (MD-CT) in the diagnosis of uncertain open globe injuries

    Energy Technology Data Exchange (ETDEWEB)

    Hoffstetter, P.; Schreyer, A.G.; Jung, E.M.; Heiss, P.; Zorger, N. [Inst. fuer Roentgendiagnostik, Universitaetsklinikum Regensburg (Germany); Schreyer, C.I.; Framme, C. [Klink und Poliklinik fuer Augenheilkunde, Universitaetsklinikum Regensburg (Germany)

    2010-02-15

    Purpose: To evaluate the significance of multislice CT for the diagnosis of uncertain penetrating globe injuries. Materials and Methods: Based on a retrospective chart review between 2002 and 2007, we identified 59 patients presenting with severe ocular trauma with uncertain rupture of the globe due to massive subconjunctival and/or anterior chamber hemorrhage. The IOP (intraocular pressure) was within normal range in all patients. High resolution multidetector CT (MD-CT) scans (16 slice scans) with axial and coronar reconstructions were performed in all patients. The affected eye was examined for signs of penetrating injury such as abnormal eye shape, scleral irregularities, lens dislocation or intravitreal hemorrhages. Four experienced radiologists read the CT scans independently. Beside the diagnosis, the relevant morphological criteria and the optimal plane orientation (axial or coronar) were specified. The sensitivity, specificity, and negative and positive predictive value were calculated. Additionally the interobserver variability was determined by applying the Cohen's kappa test. Surgical sclera inspections were performed in all cases as a standard of reference. The evaluations of the CT examination were compared with the surgery reports. Results: 59 patients were evaluated (42 men, 17 women). The mean age was 29 years (range 7-91). In 17 patients a rupture of the globe was diagnosed during surgery. 12 of these 17 penetrating injuries (70.6%) were classified correctly by MDCT, 5 of the 17 (29.4%) were not detectable. 42 patients did not have an open globe injury. 41 of these patients were diagnosed correctly negative by MDCT, and one patient was classified false positive. This results in a sensitivity of 70% with a specificity of 98%. There was high inter-rater agreement with kappa values between 0.89-0.96. Most discrepancies were caused by wrong negative findings. The most frequent morphologic criteria for open globe injury were the deformation (n

  7. Decision-making under pressure: medical errors in uncertain and dynamic environments.

    Science.gov (United States)

    Zavala, Alicia M; Day, Gary E; Plummer, David; Bamford-Wade, Anita

    2017-06-05

    Objective This paper provides a narrative overview of the literature concerning clinical decision-making processes when staff come under pressure, particularly in uncertain, dynamic and emergency situations.Methods Studies between 1980 and 2015 were analysed using a six-phase thematic analysis framework to achieve an in-depth understanding of the complex origins of medical errors that occur when people and systems are under pressure and how work pressure affects clinical performance and patient outcomes. Literature searches were conducted using a Summons Search Service platform; search criteria included a variety of methodologies, resulting in the identification of 95 papers relevant to the present review.Results Six themes emerged in the present narrative review using thematic analysis: organisational systems, workload, time pressure, teamwork, individual human factors and case complexity. This analysis highlights that clinical outcomes in emergency situations are the result of a variety of interconnecting factors. These factors may affect the ability of clinical staff in emergency situations to provide quality, safe care in a timely manner.Conclusions The challenge for researchers is to build the body of knowledge concerning the safe management of patients, particularly where clinicians are working under pressure. This understanding is important for developing pathways that optimise clinical decision making in uncertain and dynamic environments.What is known about the topic? Emergency departments (EDs) are characterised by high complexity, high throughput and greater uncertainty compared with routine hospital wards or out-patient situations, and the ED is therefore prone to unpredictable workflows and non-replicable conditions when presented with unique and complex cases.What does this paper add? Clinical decision making can be affected by pressures with complex origins, including organisational systems, workload, time constraints, teamwork, human factors and

  8. An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks

    Science.gov (United States)

    2014-01-01

    Background Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. Methods In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. Results The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. Conclusions The algorithm of probability graph isomorphism

  9. An novel frequent probability pattern mining algorithm based on circuit simulation method in uncertain biological networks.

    Science.gov (United States)

    He, Jieyue; Wang, Chunyan; Qiu, Kunpu; Zhong, Wei

    2014-01-01

    Motif mining has always been a hot research topic in bioinformatics. Most of current research on biological networks focuses on exact motif mining. However, due to the inevitable experimental error and noisy data, biological network data represented as the probability model could better reflect the authenticity and biological significance, therefore, it is more biological meaningful to discover probability motif in uncertain biological networks. One of the key steps in probability motif mining is frequent pattern discovery which is usually based on the possible world model having a relatively high computational complexity. In this paper, we present a novel method for detecting frequent probability patterns based on circuit simulation in the uncertain biological networks. First, the partition based efficient search is applied to the non-tree like subgraph mining where the probability of occurrence in random networks is small. Then, an algorithm of probability isomorphic based on circuit simulation is proposed. The probability isomorphic combines the analysis of circuit topology structure with related physical properties of voltage in order to evaluate the probability isomorphism between probability subgraphs. The circuit simulation based probability isomorphic can avoid using traditional possible world model. Finally, based on the algorithm of probability subgraph isomorphism, two-step hierarchical clustering method is used to cluster subgraphs, and discover frequent probability patterns from the clusters. The experiment results on data sets of the Protein-Protein Interaction (PPI) networks and the transcriptional regulatory networks of E. coli and S. cerevisiae show that the proposed method can efficiently discover the frequent probability subgraphs. The discovered subgraphs in our study contain all probability motifs reported in the experiments published in other related papers. The algorithm of probability graph isomorphism evaluation based on circuit simulation

  10. C-reactive protein +1444CT (rs1130864) genetic polymorphism is associated with the susceptibility to systemic lupus erythematosus and C-reactive protein levels.

    Science.gov (United States)

    Delongui, Francieli; Lozovoy, Marcell Allyson Batisti; Iriyoda, Tatiana Mayiumi Veiga; Costa, Neide Tomimura; Stadtlober, Nicole Perugini; Alfieri, Daniela Frizon; Flauzino, Tamires; Dichi, Isaias; Simão, Andréa Name Colado; Reiche, Edna Maria Vissoci

    2017-08-01

    The T rare allele of +1444CT (rs1130864) polymorphism of C-reactive protein (CRP) has been associated with increased CRP levels in some inflammatory conditions, but its role on systemic lupus erythematosus (SLE) susceptibility and on CRP levels in SLE patients remains uncertain. The objective of the study was to evaluate the association between the rs1130864 CRP polymorphism with SLE susceptibility, disease activity, and CRP levels in SLE Brazilian patients. The study enrolled 176 SLE patients and 137 controls. SLE disease activity was assessed using the SLE Disease Activity Index (SLEDAI). The rs1130864 CRP polymorphism was determined using polymerase chain reaction and restriction fragment length polymorphism. SLE patients presented higher body mass index (p = 0.046) and CRP levels (p = 0.017) than controls. The genotype and allele frequencies of patients differed from controls [CC vs. CT = odds ratio (OR) 1.730, 95% confidence interval (CI) 1.068-2.803, p = 0.035; CC vs. TT = OR 3.667, 95% CI 1.410-9.533, p = 0.009; C vs. T = OR 1.883, 95% CI 1.299-2.728, p = 0.001)]. Patients carrying the T allele presented higher CRP levels (p = 0.009), were more frequent Caucasians (p = 0.018), and with no use of immunosuppressive treatment (p = 0.004) than those carrying the C allele. However, the SLEDAI and anti-double-stranded DNA positivity did not differ from those carrying T vs. C allele (p = 0.595 and p = 0.243, respectively). The rs1130864 CRP polymorphism was associated with SLE susceptibility and CRP levels, but not with disease activity, suggesting that this polymorphism may play a role in the pathophysiology of SLE through increasing the CRP that, probably, plays an inflammatory role in SLE pathophysiology.

  11. Quantify uncertain emergency search techniques (QUEST) -- Theory and user`s guide

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, M.M.; Goldsby, M.E.; Plantenga, T.D.; Porter, T.L.; West, T.H.; Wilcox, W.B. [Sandia National Labs., Livermore, CA (United States). Systems Studies Dept.; Hensley, W.K. [Pacific Northwest National Lab., Richland, WA (United States). Nuclear Chemistry Section

    1998-01-01

    As recent world events show, criminal and terrorist access to nuclear materials is a growing national concern. The national laboratories are taking the lead in developing technologies to counter these potential threats to the national security. Sandia National laboratories, with support from Pacific Northwest National Laboratory and the Bechtel Nevada, Remote Sensing Laboratory, has developed QUEST (a model to Quantify Uncertain Emergency Search Techniques), to enhance the performance of organizations in the search for lost or stolen nuclear material. In addition, QUEST supports a wide range of other applications, such as environmental monitoring, nuclear facilities inspections, and searcher training. QUEST simulates the search for nuclear materials and calculates detector response for various source types and locations. The probability of detecting a radioactive source during a search is a function of many different variables, including source type, search location and structure geometry (including shielding), search dynamics (path and speed), and detector type and size. Through calculation of dynamic detector response, QUEST makes possible quantitative comparisons of various sensor technologies and search patterns. The QUEST model can be used as a tool to examine the impact of new detector technologies, explore alternative search concepts, and provide interactive search/inspector training.

  12. Dynamic Learning from Adaptive Neural Control of Uncertain Robots with Guaranteed Full-State Tracking Precision

    Directory of Open Access Journals (Sweden)

    Min Wang

    2017-01-01

    Full Text Available A dynamic learning method is developed for an uncertain n-link robot with unknown system dynamics, achieving predefined performance attributes on the link angular position and velocity tracking errors. For a known nonsingular initial robotic condition, performance functions and unconstrained transformation errors are employed to prevent the violation of the full-state tracking error constraints. By combining two independent Lyapunov functions and radial basis function (RBF neural network (NN approximator, a novel and simple adaptive neural control scheme is proposed for the dynamics of the unconstrained transformation errors, which guarantees uniformly ultimate boundedness of all the signals in the closed-loop system. In the steady-state control process, RBF NNs are verified to satisfy the partial persistent excitation (PE condition. Subsequently, an appropriate state transformation is adopted to achieve the accurate convergence of neural weight estimates. The corresponding experienced knowledge on unknown robotic dynamics is stored in NNs with constant neural weight values. Using the stored knowledge, a static neural learning controller is developed to improve the full-state tracking performance. A comparative simulation study on a 2-link robot illustrates the effectiveness of the proposed scheme.

  13. Adaptive nonlinear model predictive control design of a flexible-link manipulator with uncertain parameters

    Science.gov (United States)

    Schnelle, Fabian; Eberhard, Peter

    2017-06-01

    This paper presents a novel adaptive nonlinear model predictive control design for trajectory tracking of flexible-link manipulators consisting of feedback linearization, linear model predictive control, and unscented Kalman filtering. Reducing the nonlinear system to a linear system by feedback linearization simplifies the optimization problem of the model predictive controller significantly, which, however, is no longer linear in the presence of parameter uncertainties and can potentially lead to an undesired dynamical behaviour. An unscented Kalman filter is used to approximate the dynamics of the prediction model by an online parameter estimation, which leads to an adaptation of the optimization problem in each time step and thus to a better prediction and an improved input action. Finally, a detailed fuzzy-arithmetic analysis is performed in order to quantify the effect of the uncertainties on the control structure and to derive robustness assessments. The control structure is applied to a serial manipulator with two flexible links containing uncertain model parameters and acting in three-dimensional space.

  14. Mining of high utility-probability sequential patterns from uncertain databases.

    Directory of Open Access Journals (Sweden)

    Binbin Zhang

    Full Text Available High-utility sequential pattern mining (HUSPM has become an important issue in the field of data mining. Several HUSPM algorithms have been designed to mine high-utility sequential patterns (HUPSPs. They have been applied in several real-life situations such as for consumer behavior analysis and event detection in sensor networks. Nonetheless, most studies on HUSPM have focused on mining HUPSPs in precise data. But in real-life, uncertainty is an important factor as data is collected using various types of sensors that are more or less accurate. Hence, data collected in a real-life database can be annotated with existing probabilities. This paper presents a novel pattern mining framework called high utility-probability sequential pattern mining (HUPSPM for mining high utility-probability sequential patterns (HUPSPs in uncertain sequence databases. A baseline algorithm with three optional pruning strategies is presented to mine HUPSPs. Moroever, to speed up the mining process, a projection mechanism is designed to create a database projection for each processed sequence, which is smaller than the original database. Thus, the number of unpromising candidates can be greatly reduced, as well as the execution time for mining HUPSPs. Substantial experiments both on real-life and synthetic datasets show that the designed algorithm performs well in terms of runtime, number of candidates, memory usage, and scalability for different minimum utility and minimum probability thresholds.

  15. How Uncertain Information on Service Capacity Influences the Intermodal Routing Decision: A Fuzzy Programming Perspective

    Directory of Open Access Journals (Sweden)

    Yan Sun

    2018-01-01

    Full Text Available Capacity uncertainty is a common issue in the transportation planning field. However, few studies discuss the intermodal routing problem with service capacity uncertainty. Based on our previous study on the intermodal routing under deterministic capacity consideration, we systematically explore how service capacity uncertainty influences the intermodal routing decision. First of all, we adopt trapezoidal fuzzy numbers to describe the uncertain information of the service capacity, and further transform the deterministic capacity constraint into a fuzzy chance constraint based on fuzzy credibility measure. We then integrate such fuzzy chance constraint into the mixed-integer linear programming (MILP model proposed in our previous study to develop a fuzzy chance-constrained programming model. To enable the improved model to be effectively programmed in the standard mathematical programming software and solved by exact solution algorithms, a crisp equivalent linear reformulation of the fuzzy chance constraint is generated. Finally, we modify the empirical case presented in our previous study by replacing the deterministic service capacities with trapezoidal fuzzy ones. Using the modified empirical case, we utilize sensitivity analysis and fuzzy simulation to analyze the influence of service capacity uncertainty on the intermodal routing decision, and summarize some interesting insights that are helpful for decision makers.

  16. Transitions between child and adult mental health services: service design, philosophy and meaning at uncertain times.

    Science.gov (United States)

    Murcott, W J

    2014-09-01

    A young person's transition of care from child and adolescent mental health services to adult mental health services can be an uncertain and distressing event that can have serious ramifications for their recovery. Recognition of this across many countries and recent UK media interest in the dangers of mental health services failing young people has led practitioners to question the existing processes. This paper reviews the current theories and research into potential failings of services and encourages exploration for a deeper understanding of when and how care should be managed in the transition process for young people. Mental health nurses can play a vital role in this process and, by adopting the assumptions of this paradigm, look at transition from this unique perspective. By reviewing the current ideas related to age boundaries, service thresholds, service philosophy and service design, it is argued that the importance of the therapeutic relationship, the understanding of the cultural context of the young person and the placing of the young person in a position of autonomy and control should be central to any decision and process of transfer between two mental health services. © 2014 John Wiley & Sons Ltd.

  17. Robust Optimal Attitude Controller for MIMO Uncertain Hexarotor MAVs: Disturbance Observer-Based

    Directory of Open Access Journals (Sweden)

    Nurul Dayana Salim

    2016-01-01

    Full Text Available This paper proposes a robust optimal attitude control design for multiple-input, multiple-output (MIMO uncertain hexarotor micro aerial vehicles (MAVs in the presence of parametric uncertainties, external time-varying disturbances, nonlinear dynamics, and coupling. The parametric uncertainties, external time-varying disturbances, nonlinear dynamics, and coupling are treated as the total disturbance in the proposed design. The proposed controller is achieved in two simple steps. First, an optimal linear-quadratic regulator (LQR controller is designed to guarantee that the nominal closed-loop system is asymptotically stable without considering the total disturbance. After that, a disturbance observer is integrated into the closed-loop system to estimate the total disturbance acting on the system. The total disturbance is compensated by a compensation input based on the estimated total disturbance. Robust properties analysis is given to prove that the state is ultimately bounded in specified boundaries. Simulation results illustrate the robustness of the disturbance observer-based optimal attitude control design for hovering and aggressive flight missions in the presence of the total disturbance.

  18. Ethics under uncertainty: the morality and appropriateness of utilitarianism when outcomes are uncertain.

    Science.gov (United States)

    Kortenkamp, Katherine V; Moore, Colleen F

    2014-01-01

    Real-life moral dilemmas inevitably involve uncertainty, yet research has not considered how uncertainty affects utilitarian moral judgments. In addition, even though moral dilemma researchers regularly ask respondents, "What is appropriate?" but interpret it to mean, "What is moral?," little research has examined whether a difference exists between asking these 2 types of questions. In this study, 140 college students read moral dilemmas that contained certain or uncertain consequences and then responded as to whether it was appropriate and whether it was moral to kill 1 to save many (a utilitarian choice). Ratings of the appropriateness and morality of the utilitarian choice were lower under uncertainty than certainty. A follow-up experiment found that these results could not be explained entirely by a change in the expected values of the outcomes or a desire to avoid the worst-case scenario. In addition, the utilitarian choice to kill 1 to save many was rated as more appropriate than moral. The results imply that moral decision making may depend critically on whether uncertainties in outcomes are admitted and whether people are asked about appropriateness or morality.

  19. Complementary Variety: When Can Cooperation in Uncertain Environments Outperform Competitive Selection?

    Directory of Open Access Journals (Sweden)

    Martin Hilbert

    2017-01-01

    Full Text Available Evolving biological and socioeconomic populations can sometimes increase their growth rate by cooperatively redistributing resources among their members. In unchanging environments, this simply comes down to reallocating resources to fitter types. In uncertain and fluctuating environments, cooperation cannot always outperform blind competitive selection. When can it? The conditions depend on the particular shape of the fitness landscape. The article derives a single measure that quantifies by how much an intervention in stochastic environments can possibly outperform the blind forces of natural selection. It is a multivariate and multilevel measure that essentially quantifies the amount of complementary variety between different population types and environmental states. The more complementary the fitness of types in different environmental states, the proportionally larger the potential benefit of strategic cooperation over competitive selection. With complementary variety, holding population shares constant will always outperform natural and market selection (including bet-hedging, portfolio management, and stochastic switching. The result can be used both to determine the acceptable cost of learning the details of a fitness landscape and to design multilevel classification systems of population types and environmental states that maximize population growth. Two empirical cases are explored, one from the evolving economy and the other one from migrating birds.

  20. Modeling and Optimization of Stochastic Joint Replenishment and Delivery Scheduling Problem with Uncertain Costs

    Directory of Open Access Journals (Sweden)

    Lin Wang

    2013-01-01

    Full Text Available The stochastic joint replenishment and delivery scheduling (JRD problem is a key issue in supply chain management and is a major concern for companies. So far, all of the work on stochastic JRDs is under explicit environment. However, the decision makers often have to face vague operational conditions. We develop a practical JRD model with stochastic demand under fuzzy backlogging cost, fuzzy minor ordering cost, and fuzzy inventory holding cost. The problem is to determine procedures for inventory management and vehicle routing simultaneously so that the warehouse may satisfy demand at a minimum long-run average cost. Subsequently, the fuzzy total cost is defuzzified by the graded mean integration representation and centroid approaches to rank fuzzy numbers. To find optimal coordinated decisions, a modified adaptive differential evolution algorithm (MADE is utilized to find the minimum long-run average total cost. Results of numerical examples indicate that the proposed JRD model can be used to simulate fuzzy environment efficiently, and the MADE outperforms genetic algorithm with a lower total cost and higher convergence rate. The proposed methods can be applied to many industries and can help obtaining optimal decisions under uncertain environment.