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Sample records for failure assessment diagram

  1. Failure Assessment Diagram for Titanium Brazed Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yury; Jones, Justin S.; Powell, Mollie M.; Puckett, David F.

    2011-01-01

    The interaction equation was used to predict failure in Ti-4V-6Al joints brazed with Al 1100 filler metal. The joints used in this study were geometrically similar to the joints in the brazed beryllium metering structure considered for the ATLAS telescope. This study confirmed that the interaction equation R(sub sigma) + R(sub Tau) = 1, where R(sub sigma) and R(sub Tau)are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in ATLAS brazed joints as well as for construction of the Failure Assessment Diagram (FAD).

  2. Failure Assessment Diagram for Brazed 304 Stainless Steel Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yory

    2011-01-01

    Interaction equations were proposed earlier to predict failure in Albemet 162 brazed joints. Present study demonstrates that the same interaction equations can be used for lower bound estimate of the failure criterion in 304 stainless steel joints brazed with silver-based filler metals as well as for construction of the Failure Assessment Diagrams (FAD).

  3. Evaluation of Brazed Joints Using Failure Assessment Diagram

    NASA Technical Reports Server (NTRS)

    Flom, Yury

    2012-01-01

    Fitness-for service approach was used to perform structural analysis of the brazed joints consisting of several base metal / filler metal combinations. Failure Assessment Diagrams (FADs) based on tensile and shear stress ratios were constructed and experimentally validated. It was shown that such FADs can provide a conservative estimate of safe combinations of stresses in the brazed joints. Based on this approach, Margins of Safety (MS) of the brazed joints subjected to multi-axial loading conditions can be evaluated..

  4. Application of the failure assessment diagram to the evaluation of pressure-temperature limits for a pressurized water reactor

    SciTech Connect

    Yoon, K.K.; Bloom, J.M.; Pavinich, W.A.; Slager, H.W.

    1984-06-01

    The failure assessment diagram approach, an elastic-plastic fracture mechanics procedure based on the J-integral concept, was used in the evaluation of pressure-temperature (P-T) limits for the beltline region of the vessel of a pressurized water reactor. The main objective of this paper is to illustrate the application of an alternate fracture mechanics method for the evaluation of pressure-temperature limits, as allowed by Title 10, Code of Federal Regulation Part 50 (10 CFR 50), Appendix G. The evaluation of P-T limits for the beltline region of a pressurized water reactor vessel was based on the following assumptions: ASME Pressure Vessel and Piping Code, Section III, Appendix G reference flaw End-of-life fluence level in the beltline region Longitudinal flaw in the beltline weld J-resistance material toughness curves obtained from the U.S. Nuclear Regulatory Commission's Heavy Section Steel Technology (HSST) program Other material properties obtained from the Babcock and Wilcox Integrated Reactor Vessel Material Surveillance Program The maximum allowable pressure levels were calculated at 33 time points along the given bulk coolant temperature history representing the normal operation of a pressurized water reactor. The results of the calculations showed that adequate margins of safety on operating pressure for the critical weld in the beltline of the pressurized water reactor vessel are assured.

  5. Application of ISO22000, failure mode, and effect analysis (FMEA) cause and effect diagrams and pareto in conjunction with HACCP and risk assessment for processing of pastry products.

    PubMed

    Varzakas, Theodoros H

    2011-09-01

    The Failure Mode and Effect Analysis (FMEA) model has been applied for the risk assessment of pastry processing. A tentative approach of FMEA application to the pastry industry was attempted in conjunction with ISO22000. Preliminary Hazard Analysis was used to analyze and predict the occurring failure modes in a food chain system (pastry processing plant), based on the functions, characteristics, and/or interactions of the ingredients or the processes, upon which the system depends. Critical Control points have been identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram, and fishbone diagram). In this work a comparison of ISO22000 analysis with HACCP is carried out over pastry processing and packaging. However, the main emphasis was put on the quantification of risk assessment by determining the Risk Priority Number (RPN) per identified processing hazard. Storage of raw materials and storage of final products at -18°C followed by freezing were the processes identified as the ones with the highest RPN (225, 225, and 144 respectively) and corrective actions were undertaken. Following the application of corrective actions, a second calculation of RPN values was carried out leading to considerably lower values (below the upper acceptable limit of 130). It is noteworthy that the application of Ishikawa (Cause and Effect or Tree diagram) led to converging results thus corroborating the validity of conclusions derived from risk assessment and FMEA. Therefore, the incorporation of FMEA analysis within the ISO22000 system of a pastry processing industry is considered imperative.

  6. Failure Diagram for Chemically Assisted Crack Growth

    NASA Astrophysics Data System (ADS)

    Sadananda, K.; Vasudevan, A. K.

    2011-02-01

    A failure diagram that combines the thresholds for failure of a smooth specimen to that of a fracture mechanics specimen, similar to the modified Kitagawa diagram in fatigue, is presented. For a given material/environment system, the diagram defines conditions under which a crack initiated at the threshold stress in a smooth specimen becomes a propagating crack, by satisfying the threshold stress intensity of a long crack. In analogy with fatigue, it is shown that internal stresses or local stress concentrations are required to provide the necessary mechanical crack tip driving forces, on one hand, and reaction/transportation kinetics to provide the chemical potential gradients, on the other. Together, they help in the initiation and propagation of the cracks. The chemical driving forces can be expressed as equivalent mechanical stresses using the failure diagram. Both internal stresses and their gradients, in conjunction with the chemical driving forces, have to meet the minimum magnitude and the minimum gradients to sustain the growth of a microcrack formed. Otherwise, nonpropagating conditions will prevail or a crack formed will remain dormant. It is shown that the processes underlying the crack nucleation in a smooth specimen and the crack growth of a fracture mechanics specimen are essentially the same. Both require building up of internal stresses by local plasticity. The process involves intermittent crack tip blunting and microcrack nucleation until the crack becomes unstable under the applied stress.

  7. Automatically Assessing Graph-Based Diagrams

    ERIC Educational Resources Information Center

    Thomas, Pete; Smith, Neil; Waugh, Kevin

    2008-01-01

    To date there has been very little work on the machine understanding of imprecise diagrams, such as diagrams drawn by students in response to assessment questions. Imprecise diagrams exhibit faults such as missing, extraneous and incorrectly formed elements. The semantics of imprecise diagrams are difficult to determine. While there have been…

  8. A comparative study of wide plate behavior of a range of structural steels using the failure assessment diagram

    SciTech Connect

    Bannister, A.C.; Harrison, P.L.

    1995-12-31

    In the field of structural integrity assessments, attention is currently focused on the ability of such methods to conservatively predict the deformation and fracture behavior of structural steels and their weldments. In the current paper, the results of a series of wide plate tests on a range of structural steels are presented and the results assessed in terms of CTOD-strain relationships, BS PD 6493 Levels 2 and 3, and the crack driving force approach. The behavior of the large scale tests and the results of the various analyses are assessed with regard to the stress-strain characteristics of the individual steels. In a second step, the approach is extended to the assessment of a number of wide plate tests comprising welded joints with mismatched strength levels. Over, under and even-matched welded plates are compared with the behavior of normalized and Quenched and Tempered parent plates. The study demonstrates that the behavior of parent material wide plate tests can vary widely depending on the stress-strain characteristics of the material. The different behavior is a result of the consecutive effects of different steel processing conditions, microstructure, yield to tensile strength ratio and strain hardening exponent. These features are also manifested, to a lesser or greater extent, in the results of wide plate tests on welded plates of mismatched strength. Studies on mismatch effects should therefore include equal attention to the stress-strain characteristics of the parent materials as this may, in some circumstances, dominate any effects of weld strength mismatch.

  9. Using Dynamic Master Logic Diagram for component partial failure analysis

    SciTech Connect

    Ni, T.; Modarres, M.

    1996-12-01

    A methodology using the Dynamic Master Logic Diagram (DMLD) for the evaluation of component partial failure is presented. Since past PRAs have not focused on partial failure effects, the reliability of components are only based on the binary state assumption, i.e. defining a component as fully failed or functioning. This paper is to develop an approach to predict and estimate the component partial failure on the basis of the fuzzy state assumption. One example of the application of this methodology with the reliability function diagram of a centrifugal pump is presented.

  10. The Problem of Labels in E-Assessment of Diagrams

    ERIC Educational Resources Information Center

    Jayal, Ambikesh; Shepperd, Martin

    2009-01-01

    In this article we explore a problematic aspect of automated assessment of diagrams. Diagrams have partial and sometimes inconsistent semantics. Typically much of the meaning of a diagram resides in the labels; however, the choice of labeling is largely unrestricted. This means a correct solution may utilize differing yet semantically equivalent…

  11. Using Tree Diagrams as an Assessment Tool in Statistics Education

    ERIC Educational Resources Information Center

    Yin, Yue

    2012-01-01

    This study examines the potential of the tree diagram, a type of graphic organizer, as an assessment tool to measure students' knowledge structures in statistics education. Students' knowledge structures in statistics have not been sufficiently assessed in statistics, despite their importance. This article first presents the rationale and method…

  12. Application of Failure Mode and Effect Analysis (FMEA), cause and effect analysis, and Pareto diagram in conjunction with HACCP to a corn curl manufacturing plant.

    PubMed

    Varzakas, Theodoros H; Arvanitoyannis, Ioannis S

    2007-01-01

    The Failure Mode and Effect Analysis (FMEA) model has been applied for the risk assessment of corn curl manufacturing. A tentative approach of FMEA application to the snacks industry was attempted in an effort to exclude the presence of GMOs in the final product. This is of crucial importance both from the ethics and the legislation (Regulations EC 1829/2003; EC 1830/2003; Directive EC 18/2001) point of view. The Preliminary Hazard Analysis and the Fault Tree Analysis were used to analyze and predict the occurring failure modes in a food chain system (corn curls processing plant), based on the functions, characteristics, and/or interactions of the ingredients or the processes, upon which the system depends. Critical Control points have been identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram, and the fishbone diagram). Finally, Pareto diagrams were employed towards the optimization of GMOs detection potential of FMEA.

  13. Acute Effects of Vagotomy on Baroreflex Equilibrium Diagram in Rats with Chronic Heart Failure

    PubMed Central

    Kawada, Toru; Li, Meihua; Zheng, Can; Sugimachi, Masaru

    2016-01-01

    The arterial baroreflex system can be divided into the neural arc, from pressure input to efferent sympathetic nerve activity (SNA), and the peripheral arc, from SNA to arterial pressure (AP). Plotting the neural and peripheral arcs on a pressure–SNA plane yields a baroreflex equilibrium diagram. We examined the effects of vagotomy on the open-loop static characteristics of the carotid sinus baroreflex in normal control rats (NC, n = 10) and rats with heart failure after myocardial infarction (MI, n = 10). In the NC group, vagotomy shifted the neural arc toward higher SNA and decreased the slope of the peripheral arc. Consequently, the operating-point SNA increased without a significant change in the operating-point AP on the baroreflex equilibrium diagram. These vagotomy-induced effects were not observed in the MI group, suggesting a loss of vagal modulation of the carotid sinus baroreflex function in heart failure. PMID:27594790

  14. A new model of Ishikawa diagram for quality assessment

    NASA Astrophysics Data System (ADS)

    Liliana, Luca

    2016-11-01

    The paper presents the results of a study concerning the use of the Ishikawa diagram in analyzing the causes that determine errors in the evaluation of theparts precision in the machine construction field. The studied problem was"errors in the evaluation of partsprecision” and this constitutes the head of the Ishikawa diagram skeleton.All the possible, main and secondary causes that could generate the studied problem were identified. The most known Ishikawa models are 4M, 5M, 6M, the initials being in order: materials, methods, man, machines, mother nature, measurement. The paper shows the potential causes of the studied problem, which were firstly grouped in three categories, as follows: causes that lead to errors in assessing the dimensional accuracy, causes that determine errors in the evaluation of shape and position abnormalities and causes for errors in roughness evaluation. We took into account the main components of parts precision in the machine construction field. For each of the three categories of causes there were distributed potential secondary causes on groups of M (man, methods, machines, materials, environment/ medio ambiente-sp.). We opted for a new model of Ishikawa diagram, resulting from the composition of three fish skeletons corresponding to the main categories of parts accuracy.

  15. Students' Understanding of Diagrams for Solving Word Problems: A Framework for Assessing Diagram Proficiency

    ERIC Educational Resources Information Center

    Poch, Apryl L.; van Garderen, Delinda; Scheuermann, Amy M.

    2015-01-01

    A visual representation, such as a diagram, can be a powerful strategy for solving mathematical word problems. However, using a representation to solve mathematical word problems is not as simple as it seems! Many students with learning disabilities struggle to use a diagram effectively and efficiently. This article provides a framework for…

  16. Failure Assessment of Stainless Steel and Titanium Brazed Joints

    NASA Technical Reports Server (NTRS)

    Flom, Yury A.

    2012-01-01

    Following successful application of Coulomb-Mohr and interaction equations for evaluation of safety margins in Albemet 162 brazed joints, two additional base metal/filler metal systems were investigated. Specimens consisting of stainless steel brazed with silver-base filler metal and titanium brazed with 1100 Al alloy were tested to failure under combined action of tensile, shear, bending and torsion loads. Finite Element Analysis (FEA), hand calculations and digital image comparison (DIC) techniques were used to estimate failure stresses and construct Failure Assessment Diagrams (FAD). This study confirms that interaction equation R(sub sigma) + R(sub tau) = 1, where R(sub sigma) and R(sub t u) are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in stainless steel and titanium brazed joints.

  17. A Triaxial Failure Diagram to predict the forming limit of 3D sheet metal parts subjected to multiaxial stresses

    NASA Astrophysics Data System (ADS)

    Rastellini, F.; Socorro, G.; Forgas, A.; Onate, E.

    2016-08-01

    Accurate prediction of failure and forming limits is essential when modelling sheet metal forming processes. Since traditional Forming Limit Curves (FLCs) are not valid for materials subjected to triaxial loading, a new failure criterion is proposed in this paper based on the stress triaxility and the effective plastic strain accumulated during the history of material loading. Formability zones are identified inside the proposed Triaxial Failure Diagram (TFD). FLCs may be mapped into the TFD defining a new Triaxial Failure Curve, or it can be defined by triaxial failure experiments. Several TFD examples are validated and constrasted showing acceptable accuracy in the numerical prediction of forming failure/limit of 3D thick sheet parts.

  18. Assessment of failure of cemented polyethylene acetabular component due to bone remodeling: A finite element study.

    PubMed

    Ghosh, Rajesh

    2016-09-01

    The aim of the study is to determine failure of the cemented polyethylene acetabular component, which might occur due to excessive bone resorption, cement-bone interface debonding and fatigue failure of the cement mantle. Three-dimensional finite element models of intact and implanted pelvic bone were developed and bone remodeling algorithm was implemented for present analysis. Soderberg fatigue failure diagram was used for fatigue assessment of the cement mantle. Hoffman failure criterion was considered for prediction of cement-bone interface debonding. Results indicate fatigue failure of the cement mantle and implant-bone interface debonding might not occur due to bone remodeling.

  19. Failure Assessment of Brazed Structures

    NASA Technical Reports Server (NTRS)

    Flom, Yuri

    2012-01-01

    Despite the great advances in analytical methods available to structural engineers, designers of brazed structures have great difficulties in addressing fundamental questions related to the loadcarrying capabilities of brazed assemblies. In this chapter we will review why such common engineering tools as Finite Element Analysis (FEA) as well as many well-established theories (Tresca, von Mises, Highest Principal Stress, etc) don't work well for the brazed joints. This chapter will show how the classic approach of using interaction equations and the less known Coulomb-Mohr failure criterion can be employed to estimate Margins of Safety (MS) in brazed joints.

  20. Renal function assessment in heart failure.

    PubMed

    Pérez Calvo, J I; Josa Laorden, C; Giménez López, I

    2017-03-01

    Renal function is one of the most consistent prognostic determinants in heart failure. The prognostic information it provides is independent of the ejection fraction and functional status. This article reviews the various renal function assessment measures, with special emphasis on the fact that the patient's clinical situation and response to the heart failure treatment should be considered for the correct interpretation of the results. Finally, we review the literature on the performance of tubular damage biomarkers.

  1. Nanoparticles in the environment: assessment using the causal diagram approach

    PubMed Central

    2012-01-01

    Nanoparticles (NPs) cause concern for health and safety as their impact on the environment and humans is not known. Relatively few studies have investigated the toxicological and environmental effects of exposure to naturally occurring NPs (NNPs) and man-made or engineered NPs (ENPs) that are known to have a wide variety of effects once taken up into an organism. A review of recent knowledge (between 2000-2010) on NP sources, and their behaviour, exposure and effects on the environment and humans was performed. An integrated approach was used to comprise available scientific information within an interdisciplinary logical framework, to identify knowledge gaps and to describe environment and health linkages for NNPs and ENPs. The causal diagram has been developed as a method to handle the complexity of issues on NP safety, from their exposure to the effects on the environment and health. It gives an overview of available scientific information starting with common sources of NPs and their interactions with various environmental processes that may pose threats to both human health and the environment. Effects of NNPs on dust cloud formation and decrease in sunlight intensity were found to be important environmental changes with direct and indirect implication in various human health problems. NNPs and ENPs exposure and their accumulation in biological matrices such as microbiota, plants and humans may result in various adverse effects. The impact of some NPs on human health by ROS generation was found to be one of the major causes to develop various diseases. A proposed cause-effects diagram for NPs is designed considering both NNPs and ENPs. It represents a valuable information package and user-friendly tool for various stakeholders including students, researchers and policy makers, to better understand and communicate on issues related to NPs. PMID:22759495

  2. Assessment of Nonorganic Failure To Thrive.

    ERIC Educational Resources Information Center

    Wooster, Donna M.

    1999-01-01

    This article describes basic assessment considerations for infants and toddlers exhibiting nonorganic failure to thrive. The evaluation process must examine feeding, maternal-child interactions, child temperament, and environmental risks and behaviors. Early identification and intervention are necessary to minimize the long-term developmental…

  3. Insulation failure assessment under random energization overvoltages

    SciTech Connect

    Mahdy, A.M.; Anis, H.I.; El-Morshedy, A.

    1996-03-01

    This paper offers a new simple approach to the evaluation of the risk of failure of external insulation in view of their known probabilistic nature. This is applied to EHV transmission systems subjected to energization overvoltages. The randomness, both in the applied stresses and insulation`s withstand characteristics are numerically simulated and then integrated to assess the risk of failure. Overvoltage control methods are accounted for, such as the use of pre-insertion breaker resistors, series capacitive compensation, and the installation of shunt reactors.

  4. Failure detection system risk reduction assessment

    NASA Technical Reports Server (NTRS)

    Aguilar, Robert B. (Inventor); Huang, Zhaofeng (Inventor)

    2012-01-01

    A process includes determining a probability of a failure mode of a system being analyzed reaching a failure limit as a function of time to failure limit, determining a probability of a mitigation of the failure mode as a function of a time to failure limit, and quantifying a risk reduction based on the probability of the failure mode reaching the failure limit and the probability of the mitigation.

  5. Use of Influence Diagrams and Fuzzy Theory to Develop Assessment Method of Organizational Influences on Component Maintenance

    SciTech Connect

    Yoonik Kim; Kwang-Won Ahn; Chang-Hyun Chung; Kil Yoo Kim; Joon-Eon Yang

    2002-07-01

    Organization can make influences on all the systems. Especially in case of nuclear power plants in which safety is established to be one of the most important operating goals, there have been a lot of research efforts for the hardware advancement. However in recent years, it has been widely recognized that organizational factors in nuclear power plants have an important influence on the safety attitudes and the safe behavior of individuals. Until now, any means to include assessments of organizational structure in probabilistic risk assessments have not been universally accepted. The objective of this work is to develop a method to assess organizational influences on component maintenance. Influence diagrams are introduced in this method as a decision making tool and fuzzy theory is used to reflect the vagueness in considering relevance of human activities in maintenance tasks. Introducing fuzzy theory to assess the organizational factors is deemed to a somewhat new trial, which makes it possible to convert linguistic vague descriptions into mathematical ones. Fuzzy linguistic descriptions offer an alternative and often complementary language to conventional, i.e., analytic approaches to modeling systems. Among the existing methodologies to assess organizational factors, the concept of the {omega}-factor model is utilized and the mechanism that organizational factors have influences on component maintenance is evaluated through composing influence diagrams. These influences go to failure rates and eventually affect component unavailability. Further study will make it possible that the influences of organizational factors on human error probabilities are incorporated into human reliability analysis and furthermore probabilistic safety assessment. (authors)

  6. Derivation of Failure Rates and Probability of Failures for the International Space Station Probabilistic Risk Assessment Study

    NASA Technical Reports Server (NTRS)

    Vitali, Roberto; Lutomski, Michael G.

    2004-01-01

    National Aeronautics and Space Administration s (NASA) International Space Station (ISS) Program uses Probabilistic Risk Assessment (PRA) as part of its Continuous Risk Management Process. It is used as a decision and management support tool to not only quantify risk for specific conditions, but more importantly comparing different operational and management options to determine the lowest risk option and provide rationale for management decisions. This paper presents the derivation of the probability distributions used to quantify the failure rates and the probability of failures of the basic events employed in the PRA model of the ISS. The paper will show how a Bayesian approach was used with different sources of data including the actual ISS on orbit failures to enhance the confidence in results of the PRA. As time progresses and more meaningful data is gathered from on orbit failures, an increasingly accurate failure rate probability distribution for the basic events of the ISS PRA model can be obtained. The ISS PRA has been developed by mapping the ISS critical systems such as propulsion, thermal control, or power generation into event sequences diagrams and fault trees. The lowest level of indenture of the fault trees was the orbital replacement units (ORU). The ORU level was chosen consistently with the level of statistically meaningful data that could be obtained from the aerospace industry and from the experts in the field. For example, data was gathered for the solenoid valves present in the propulsion system of the ISS. However valves themselves are composed of parts and the individual failure of these parts was not accounted for in the PRA model. In other words the failure of a spring within a valve was considered a failure of the valve itself.

  7. Assessment of hoist failure rate for Payload Transporter III

    SciTech Connect

    Demmie, P.N.

    1994-02-01

    Assessment of the hoist failure rate for the Payload Transporter Type III (PT-III) hoist was completed as one of the ground transportation tasks for the Minuteman II (MMIII) Weapon System Safety Assessment. The failures of concern are failures that lead to dropping a reentry system (RS) during hoist operations in a silo or the assembly, storage, and inspection building for a MMIII wing. After providing a brief description of the PT-III hoist system, the author summarizes his search for historical data from industry and the military services for failures of electric hoist systems. Since such information was not found, the strategy for assessing a failure rate was to consider failure mechanisms which lead to load-drop accidents, estimate their rates, and sum the rates for the PT-III hoist failure rate. The author discusses failure mechanisms and describes his assessment of a chain failure rate that is based on data from destructive testing of a chain of the type used for the PT-III hoist and projected usage rates for hoist operations involving the RS. The main result provides upper bounds for chain failure rates that are based on these data. No test data were found to estimate failure rates due to mechanisms other than chain failure. The author did not attempt to quantify the effects of human factors on the PT-III hoist failure rate.

  8. European Extremely Large Telescope (E-ELT) availability stochastic model: integrating failure mode and effect analysis (FMEA), influence diagram, and Bayesian network together

    NASA Astrophysics Data System (ADS)

    Verzichelli, Gianluca

    2016-08-01

    An Availability Stochastic Model for the E-ELT has been developed in GeNIE. The latter is a Graphical User Interface (GUI) for the Structural Modeling, Inference, and Learning Engine (SMILE), originally distributed by the Decision Systems Laboratory from the University of Pittsburgh, and now being a product of Bayes Fusion, LLC. The E-ELT will be the largest optical/near-infrared telescope in the world. Its design comprises an Alt-Azimuth mount reflecting telescope with a 39-metre-diameter segmented primary mirror, a 4-metre-diameter secondary mirror, a 3.75-metre-diameter tertiary mirror, adaptive optics and multiple instruments. This paper highlights how a Model has been developed for an earlier on assessment of the Telescope Avail- ability. It also describes the modular structure and the underlying assumptions that have been adopted for developing the model and demonstrates the integration of FMEA, Influence Diagram and Bayesian Network elements. These have been considered for a better characterization of the Model inputs and outputs and for taking into account Degraded-based Reliability (DBR). Lastly, it provides an overview of how the information and knowledge captured in the model may be used for an earlier on definition of the Failure, Detection, Isolation and Recovery (FDIR) Control Strategy and the Telescope Minimum Master Equipment List (T-MMEL).

  9. Assessment of Steel Reinforcement Corrosion State by Parameters of Potentiodynamic Diagrams

    NASA Astrophysics Data System (ADS)

    Krajči, Ľudovít; Jerga, Ján

    2015-12-01

    The environment of the steel reinforcement has a significant impact on the durability and service life of a concrete structure. It is not only the presence of aggressive substances from the environment, but also the own composition of concrete mixture. The use of new types of cements, additives and admixtures must be preceded by verification, if they themselves shall not initiate the corrosion. There is a need for closer physical expression of the parameters of the potentiodynamic diagrams allowing reliable assessment of the influence of the surrounding environment on electrochemical behaviour of reinforcement. The analysis of zero retardation limits of potentiodynamic curves is presented.

  10. Improving FMEA risk assessment through reprioritization of failures

    NASA Astrophysics Data System (ADS)

    Ungureanu, A. L.; Stan, G.

    2016-08-01

    Most of the current methods used to assess the failure and to identify the industrial equipment defects are based on the determination of Risk Priority Number (RPN). Although conventional RPN calculation is easy to understand and use, the methodology presents some limitations, such as the large number of duplicates and the difficulty of assessing the RPN indices. In order to eliminate the afore-mentioned shortcomings, this paper puts forward an easy and efficient computing method, called Failure Developing Mode and Criticality Analysis (FDMCA), which takes into account the failures and the defect evolution in time, from failure appearance to a breakdown.

  11. Common-Cause Failure Analysis in Event Assessment

    SciTech Connect

    Dana L. Kelly; Dale M. Rasmuson

    2008-09-01

    This paper describes the approach taken by the U. S. Nuclear Regulatory Commission to the treatment of common-cause failure in probabilistic risk assessment of operational events. The approach is based upon the Basic Parameter Model for common-cause failure, and examples are illustrated using the alpha-factor parameterization, the approach adopted by the NRC in their Standardized Plant Analysis Risk (SPAR) models. The cases of a failed component (with and without shared common-cause failure potential) and a component being unavailable due to preventive maintenance or testing are addressed. The treatment of two related failure modes (e.g., failure to start and failure to run) is a new feature of this paper. These methods are being applied by the NRC in assessing the risk significance of operational events for the Significance Determination Process (SDP) and the Accident Sequence Precursor (ASP) program.

  12. Common-Cause Failure Analysis in Event Assessment

    SciTech Connect

    D. M. Rasmuson; D. L. Kelly

    2008-06-01

    This paper reviews the basic concepts of modelling common-cause failures (CCFs) in reliability and risk studies and then applies these concepts to the treatment of CCF in event assessment. The cases of a failed component (with and without shared CCF potential) and a component being unavailable due to preventive maintenance or testing are addressed. The treatment of two related failure modes (e.g. failure to start and failure to run) is a new feature of this paper, as is the treatment of asymmetry within a common-cause component group.

  13. Public Notification - RTCR Failure To Perform Level 1 Assessment Template

    EPA Pesticide Factsheets

    When a PWS fails to perform a required Level 1 Assessment, it must issue a public notice to inform the consumers of its water of that failure. You can use this template as a guide to prepare that public notice.

  14. Reliability assessment on interfacial failure of thermal barrier coatings

    NASA Astrophysics Data System (ADS)

    Guo, Jin-Wei; Yang, Li; Zhou, Yi-Chun; He, Li-Min; Zhu, Wang; Cai, Can-Ying; Lu, Chun-Sheng

    2016-10-01

    Thermal barrier coatings (TBCs) usually exhibit an uncertain lifetime owing to their scattering mechanical properties and severe service conditions. To consider these uncertainties, a reliability assessment method is proposed based on failure probability analysis. First, a limit state equation is established to demarcate the boundary between failure and safe regions, and then the failure probability is calculated by the integration of a probability density function in the failure area according to the first- or second-order moment. It is shown that the parameters related to interfacial failure follow a Weibull distribution in two types of TBC. The interfacial failure of TBCs is significantly affected by the thermal mismatch of material properties and the temperature drop in service.

  15. Probabilistic failure assessment with application to solid rocket motors

    NASA Technical Reports Server (NTRS)

    Jan, Darrell L.; Davidson, Barry D.; Moore, Nicholas R.

    1990-01-01

    A quantitative methodology is being developed for assessment of risk of failure of solid rocket motors. This probabilistic methodology employs best available engineering models and available information in a stochastic framework. The framework accounts for incomplete knowledge of governing parameters, intrinsic variability, and failure model specification error. Earlier case studies have been conducted on several failure modes of the Space Shuttle Main Engine. Work in progress on application of this probabilistic approach to large solid rocket boosters such as the Advanced Solid Rocket Motor for the Space Shuttle is described. Failure due to debonding has been selected as the first case study for large solid rocket motors (SRMs) since it accounts for a significant number of historical SRM failures. Impact of incomplete knowledge of governing parameters and failure model specification errors is expected to be important.

  16. Development and validation of standard area diagrams to aide assessment of pecan scab symptoms on pecan fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pecan scab (Fusicladium effusum) causes losses of pecan nutmeat yield and quality in the southeastern U.S. Disease assessment relies on visual rating, which can be inaccurate, imprecise with poor inter-rater reliability. A standard area diagram (SAD) set for pecan scab on fruit valves was develope...

  17. Assessing disease severity: accuracy and reliability of rater estimates in relation to number of diagrams in a standard area diagram set

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Error in rater estimates of plant disease severity occur, and standard area diagrams (SADs) help improve accuracy and reliability. The effects of diagram number in a SAD set on accuracy and reliability is unknown. The objective of this study was to compare estimates of pecan scab severity made witho...

  18. Methods for Assessing Honeycomb Sandwich Panel Wrinkling Failures

    NASA Technical Reports Server (NTRS)

    Zalewski, Bart F.; Dial, William B.; Bednarcyk, Brett A.

    2012-01-01

    Efficient closed-form methods for predicting the facesheet wrinkling failure mode in sandwich panels are assessed. Comparisons were made with finite element model predictions for facesheet wrinkling, and a validated closed-form method was implemented in the HyperSizer structure sizing software.

  19. How many standard area diagram sets are needed for accurate disease severity assessment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Standard area diagram sets (SADs) are widely used in plant pathology: a rater estimates disease severity by comparing an unknown sample to actual severities in the SADs and interpolates an estimate as accurately as possible (although some SADs have been developed for categorizing disease too). Most ...

  20. Failure of sewage pumps: statistical modelling and impact assessment.

    PubMed

    Korving, H; Geise, M; Clemens, F

    2006-01-01

    Sewage pumping stations are directly responsible for affecting performance, i.e. failing pumps may result in combined sewer overflows or flooding. However, failures of sewage pumps are not yet incorporated in sewer assessments due to lack of knowledge and data. This paper presents the analysis of pump failure data provided by two sewer management authorities in The Netherlands. Pump failures have been studied accounting for the nature of the failures, the operation and maintenance procedures of the management authority, the ageing of the pumps and the changes in the environment of pumps. The analysis shows that sewage pumps fail relatively often due to the composition of sewage and the discontinuous operation of the pumps. The interarrival time and the duration of failures are highly variable and independent of the pump type and the specific function of the pump. The results also indicate that the serviceability of sewer systems is significantly affected by failing pumps. As a consequence, part of the environmental damage due to CSOs (combined sewer overflows) can be avoided by improving maintenance of pumping stations.

  1. Methods of failure and reliability assessment for mechanical heart pumps.

    PubMed

    Patel, Sonna M; Allaire, Paul E; Wood, Houston G; Throckmorton, Amy L; Tribble, Curt G; Olsen, Don B

    2005-01-01

    Artificial blood pumps are today's most promising bridge-to-recovery (BTR), bridge-to-transplant (BTT), and destination therapy solutions for patients suffering from intractable congestive heart failure (CHF). Due to an increased need for effective, reliable, and safe long-term artificial blood pumps, each new design must undergo failure and reliability testing, an important step prior to approval from the United States Food and Drug Administration (FDA), for clinical testing and commercial use. The FDA has established no specific standards or protocols for these testing procedures and there are only limited recommendations provided by the scientific community when testing an overall blood pump system and individual system components. Product development of any medical device must follow a systematic and logical approach. As the most critical aspects of the design phase, failure and reliability assessments aid in the successful evaluation and preparation of medical devices prior to clinical application. The extent of testing, associated costs, and lengthy time durations to execute these experiments justify the need for an early evaluation of failure and reliability. During the design stages of blood pump development, a failure modes and effects analysis (FMEA) should be completed to provide a concise evaluation of the occurrence and frequency of failures and their effects on the overall support system. Following this analysis, testing of any pump typically involves four sequential processes: performance and reliability testing in simple hydraulic or mock circulatory loops, acute and chronic animal experiments, human error analysis, and ultimately, clinical testing. This article presents recommendations for failure and reliability testing based on the National Institutes of Health (NIH), Society for Thoracic Surgeons (STS) and American Society for Artificial Internal Organs (ASAIO), American National Standards Institute (ANSI), the Association for Advancement of

  2. Quantitative risk assessment for skin sensitization: Success or failure?

    PubMed

    Kimber, Ian; Gerberick, G Frank; Basketter, David A

    2017-02-01

    Skin sensitization is unique in the world of toxicology. There is a combination of reliable, validated predictive test methods for identification of skin sensitizing chemicals, a clearly documented and transparent approach to risk assessment, and effective feedback from dermatology clinics around the world delivering evidence of the success or failure of the hazard identification/risk assessment/management process. Recent epidemics of contact allergy, particularly to preservatives, have raised questions of whether the safety/risk assessment process is working in an optimal manner (or indeed is working at all!). This review has as its focus skin sensitization quantitative risk assessment (QRA). The core toxicological principles of QRA are reviewed, and evidence of use and misuse examined. What becomes clear is that skin sensitization QRA will only function adequately if two essential criteria are met. The first is that QRA is applied rigourously, and the second is that potential exposure to the sensitizing substance is assessed adequately. This conclusion will come as no surprise to any toxicologist who appreciates the basic premise that "risk = hazard x exposure". Accordingly, use of skin sensitization QRA is encouraged, not least because the essential feedback from dermatology clinics can be used as a tool to refine QRA in situations where this risk assessment tool has not been properly used.

  3. Assessment of facial form modifications in orthodontics: proposal of a modified computerized mesh diagram analysis.

    PubMed

    Ferrario, V F; Sforza, C; Dalloca, L L; DeFranco, D J

    1996-03-01

    A modified computerized mesh diagram analysis enables rapid, easy, and independent quantifications of facial size, shape, and head position. A lateral cephalometric radiograph is traced, positioned in natural head position (NHP) according to the NHP registered on a lateral photograph, and superimposed by the standard grid of rectangles determined by the patient's upper face height and face depth. The patient's tracing is compared with a reference tracing of a norm. The two tracings are registered at nasion in NHP, and the size difference of the patient's mesh rectangles from the norm is quantified by a size normalization. The shape discrepancies are evaluated by calculating relevant displacement vectors for each cephalometric landmark, and a global difference factor. This computerized method provides a rapid graphic evaluation of the patient's sagittal and vertical discrepancies and can also be applied to determine the effects of orthodontic therapy and/or growth on the skeletal and dental relationships in a single patient.

  4. [Volume assessment in the acute heart and renal failure].

    PubMed

    Vujicić, Bozidar; Ruzić, Alen; Zaputović, Luka; Racki, Sanjin

    2012-10-01

    Acute kidney injury (AKI) is an important clinical issue, especially in the setting of critical care. It has been shown in multiple studies to be a key independent risk factor for mortality, even after adjustment for demographics and severity of illness. There is wide agreement that a generally applicable classification system is required for AKI which helps to standardize estimation of severity of renal disfunction and to predict outcome associated with this condition. That's how RIFLE (Risk-Injury-Failure-Loss-End-stage renal disease), and AKIN (Acute Kidney Injury Network) classifications for AKI were found in 2004 and 2007, respectively. In the clinical setting of heart failure, a positive fluid balance (often expressed in the literature as weight gain) is used by disease management programs as a marker of heart failure decompensation. Oliguria is defined as urine output less than 0,3 ml/kg/h for at least 24 h. Since any delay in treatment can lead to a dangerous progression of the AKI, early recognition of oliguria appears to be crucial. Critically ill patients with oliguric AKI are at increased risk for fluid imbalance due to widespread systemic inflammation, reduced plasma oncotic pressure and increased capillary leak. These patients are particulary at risk of fluid overload and therefore restrictive strategy of fluid administration should be used. Objective, rapid and accurate volume assessment is important in undiagnosed patients presenting with critical illness, as errors may result in interventions with fatal outcomes. The historical tools such as physical exam, and chest radiography suffer from significant limitations. As gold standard, radioisolopic measurement of volume is impractical in the acute care enviroment. Newer technologies offer the promise of both rapid and accurate bedside estimation of volume status with the potential to improve clinical outcomes. Blood assessment with bioimpendance vector analysis, and bedside ultrasound seem to be

  5. Selected component failure rate values from fusion safety assessment tasks

    SciTech Connect

    Cadwallader, L.C.

    1998-09-01

    This report is a compilation of component failure rate and repair rate values that can be used in magnetic fusion safety assessment tasks. Several safety systems are examined, such as gas cleanup systems and plasma shutdown systems. Vacuum system component reliability values, including large vacuum chambers, have been reviewed. Values for water cooling system components have also been reported here. The report concludes with the examination of some equipment important to personnel safety, atmospheres, combustible gases, and airborne releases of radioactivity. These data should be useful to system designers to calculate scoping values for the availability and repair intervals for their systems, and for probabilistic safety or risk analysts to assess fusion systems for safety of the public and the workers.

  6. Selected Component Failure Rate Values from Fusion Safety Assessment Tasks

    SciTech Connect

    Cadwallader, Lee Charles

    1998-09-01

    This report is a compilation of component failure rate and repair rate values that can be used in magnetic fusion safety assessment tasks. Several safety systems are examined, such as gas cleanup systems and plasma shutdown systems. Vacuum system component reliability values, including large vacuum chambers, have been reviewed. Values for water cooling system components have also been reported here. The report concludes with the examination of some equipment important to personnel safety, atmospheres, combustible gases, and airborne releases of radioactivity. These data should be useful to system designers to calculate scoping values for the availability and repair intervals for their systems, and for probabilistic safety or risk analysts to assess fusion systems for safety of the public and the workers.

  7. Assessing Wind Farm Reliability Using Weather Dependent Failure Rates

    NASA Astrophysics Data System (ADS)

    Wilson, G.; McMillan, D.

    2014-06-01

    Using reliability data comprising of two modern, large scale wind farm sites and wind data from two onsite met masts, a model is developed which calculates wind speed dependant failure rates which are used to populate a Markov Chain. Monte Carlo simulation is then exercised to simulate three wind farms which are subjected to controlled wind speed conditions from three separate potential UK sites. The model then calculates and compares wind farm reliability due to corrective maintenance and component failure rates influenced by the wind speed of each of the sites. Results show that the components affected most by changes in average daily wind speed are the control system and the yaw system. A comparison between this model and a more simple estimation of site yield is undertaken. The model takes into account the effects of the wind speed on the cost of operation and maintenance and also includes the impact of longer periods of downtime in the winter months and shorter periods in the summer. By taking these factors into account a more detailed site assessment can be undertaken. There is significant value to this model for operators and manufacturers.

  8. Comparison of Body Composition Assessment Methods in Pediatric Intestinal Failure

    PubMed Central

    Mehta, Nilesh M.; Raphael, Bram; Guteirrez, Ivan; Quinn, Nicolle; Mitchell, Paul D.; Litman, Heather J.; Jaksic, Tom; Duggan, Christopher P.

    2015-01-01

    Objectives To examine the agreement of multifrequency bioelectric impedance analysis (BIA) and anthropometry with reference methods for body composition assessment in children with intestinal failure (IF). Methods We conducted a prospective pilot study in children 14 years of age or younger with IF resulting from either short bowel syndrome (SBS) or motility disorders. Bland Altman analysis was used to examine the agreement between BIA and deuterium dilution in measuring total body water (TBW) and lean body mass (LBM); and between BIA and dual X-ray absorptiometry (DXA) techniques in measuring LBM and FM. Fat mass (FM) and percent body fat (%BF) measurements by BIA and anthropometry, were also compared in relation to those measured by deuterium dilution. Results Fifteen children with IF, median (IQR) age 7.2 (5.0, 10.0) years, 10 (67%) male, were studied. BIA and deuterium dilution were in good agreement with a mean bias (limits of agreement) of 0.9 (-3.2, 5.0) for TBW (L) and 0.1 (-5.4 to 5.6) for LBM (kg) measurements. The mean bias (limits) for FM (kg) and %BF measurements were 0.4 (-3.8, 4.6) kg and 1.7 (-16.9, 20.3)% respectively. The limits of agreement were within 1 SD of the mean bias in 12/14 (86%) subjects for TBW and LBM, and in 11/14 (79%) for FM and %BF measurements. Mean bias (limits) for LBM (kg) and FM (kg) between BIA and DXA were 1.6 (-3.0 to 6.3) kg and -0.1 (-3.2 to 3.1) kg, respectively. Mean bias (limits) for FM (kg) and %BF between anthropometry and deuterium dilution were 0.2 (-4.2, 4.6) and -0.2 (-19.5 to 19.1), respectively. The limits of agreement were within 1 SD of the mean bias in 10/14 (71%) subjects. Conclusions In children with intestinal failure, TBW and LBM measurements by multifrequency BIA method were in agreement with isotope dilution and DXA methods, with small mean bias. In comparison to deuterium dilution, BIA was comparable to anthropometry for FM and %BF assessments with small mean bias. However, the limits of agreement

  9. Cutting Up Text To Make Moveable, Magnetic Diagrams: A Way of Teaching and Assessing Biological Processes.

    ERIC Educational Resources Information Center

    Britton, Lynda A.; Wandersee, James H.

    1997-01-01

    Describes a method of cutting up pages in texts to make moveable, magnetic cards that can be used for instruction and assessment. Uses the diagrammatic illustrations associated with the complicated biotechnology procedures of the polymerase chain reaction and restriction fragment length polymorphism. (JRH)

  10. A failure diagnosis and impact assessment prototype for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Baker, Carolyn G.; Marsh, Christopher A.

    1991-01-01

    NASA is investigating the use of advanced automation to enhance crew productivity for Space Station Freedom in numerous areas, one being failure management. A prototype is described that diagnoses failure sources and assesses the future impacts of those failures on other Freedom entities.

  11. Hubble Diagram

    NASA Astrophysics Data System (ADS)

    Djorgovski, S.; Murdin, P.

    2000-11-01

    Initially introduced as a way to demonstrate the expansion of the universe, and subsequently to determine the expansion rate (the HUBBLE CONSTANT H0), the Hubble diagram is one of the classical cosmological tests. It is a plot of apparent fluxes (usually expressed as magnitudes) of some types of objects at cosmological distances, against their REDSHIFTS. It is used as a tool to measure the glob...

  12. Reconciling Streamflow Uncertainty Estimation and River Bed Morphology Dynamics. Insights from a Probabilistic Assessment of Streamflow Uncertainties Using a Reliability Diagram

    NASA Astrophysics Data System (ADS)

    Morlot, T.; Mathevet, T.; Perret, C.; Favre Pugin, A. C.

    2014-12-01

    Streamflow uncertainty estimation has recently received a large attention in the literature. A dynamic rating curve assessment method has been introduced (Morlot et al., 2014). This dynamic method allows to compute a rating curve for each gauging and a continuous streamflow time-series, while calculating streamflow uncertainties. Streamflow uncertainty takes into account many sources of uncertainty (water level, rating curve interpolation and extrapolation, gauging aging, etc.) and produces an estimated distribution of streamflow for each days. In order to caracterise streamflow uncertainty, a probabilistic framework has been applied on a large sample of hydrometric stations of the Division Technique Générale (DTG) of Électricité de France (EDF) hydrometric network (>250 stations) in France. A reliability diagram (Wilks, 1995) has been constructed for some stations, based on the streamflow distribution estimated for a given day and compared to a real streamflow observation estimated via a gauging. To build a reliability diagram, we computed the probability of an observed streamflow (gauging), given the streamflow distribution. Then, the reliability diagram allows to check that the distribution of probabilities of non-exceedance of the gaugings follows a uniform law (i.e., quantiles should be equipropables). Given the shape of the reliability diagram, the probabilistic calibration is caracterised (underdispersion, overdispersion, bias) (Thyer et al., 2009). In this paper, we present case studies where reliability diagrams have different statistical properties for different periods. Compared to our knowledge of river bed morphology dynamic of these hydrometric stations, we show how reliability diagram gives us invaluable information on river bed movements, like a continuous digging or backfilling of the hydraulic control due to erosion or sedimentation processes. Hence, the careful analysis of reliability diagrams allows to reconcile statistics and long

  13. 29 CFR 2700.27 - Effect of failure to contest proposed penalty assessment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Effect of failure to contest proposed penalty assessment. 2700.27 Section 2700.27 Labor Regulations Relating to Labor (Continued) FEDERAL MINE SAFETY AND HEALTH REVIEW COMMISSION PROCEDURAL RULES Contests of Proposed Penalties § 2700.27 Effect of failure to contest proposed penalty assessment. If, within...

  14. Consequence assessment of large rock slope failures in Norway

    NASA Astrophysics Data System (ADS)

    Oppikofer, Thierry; Hermanns, Reginald L.; Horton, Pascal; Sandøy, Gro; Roberts, Nicholas J.; Jaboyedoff, Michel; Böhme, Martina; Yugsi Molina, Freddy X.

    2014-05-01

    Steep glacially carved valleys and fjords in Norway are prone to many landslide types, including large rockslides, rockfalls, and debris flows. Large rockslides and their secondary effects (rockslide-triggered displacement waves, inundation behind landslide dams and outburst floods from failure of landslide dams) pose a significant hazard to the population living in the valleys and along the fjords shoreline. The Geological Survey of Norway performs systematic mapping of unstable rock slopes in Norway and has detected more than 230 unstable slopes with significant postglacial deformation. This large number necessitates prioritisation of follow-up activities, such as more detailed investigations, periodic displacement measurements, continuous monitoring and early-warning systems. Prioritisation is achieved through a hazard and risk classification system, which has been developed by a panel of international and Norwegian experts (www.ngu.no/en-gb/hm/Publications/Reports/2012/2012-029). The risk classification system combines a qualitative hazard assessment with a consequences assessment focusing on potential life losses. The hazard assessment is based on a series of nine geomorphological, engineering geological and structural criteria, as well as displacement rates, past events and other signs of activity. We present a method for consequence assessment comprising four main steps: 1. computation of the volume of the unstable rock slope; 2. run-out assessment based on the volume-dependent angle of reach (Fahrböschung) or detailed numerical run-out modelling; 3. assessment of possible displacement wave propagation and run-up based on empirical relations or modelling in 2D or 3D; and 4. estimation of the number of persons exposed to rock avalanches or displacement waves. Volume computation of an unstable rock slope is based on the sloping local base level technique, which uses a digital elevation model to create a second-order curved surface between the mapped extent of

  15. Assessing mechanical vulnerability in water distribution networks under multiple failures

    NASA Astrophysics Data System (ADS)

    Berardi, Luigi; Ugarelli, Rita; Røstum, Jon; Giustolisi, Orazio

    2014-03-01

    Understanding mechanical vulnerability of water distribution networks (WDN) is of direct relevance for water utilities since it entails two different purposes. On the one hand, it might support the identification of severe failure scenarios due to external causes (e.g., natural or intentional events) which result into the most critical consequences on WDN supply capacity. On the other hand, it aims at figure out the WDN portions which are more prone to be affected by asset disruptions. The complexity of such analysis stems from the number of possible scenarios with single and multiple simultaneous shutdowns of asset elements leading to modifications of network topology and insufficient water supply to customers. In this work, the search for the most disruptive combinations of multiple asset failure events is formulated and solved as a multiobjective optimization problem. The higher vulnerability failure scenarios are detected as those causing the lower supplied demand due to the lower number of simultaneous failures. The automatic detection of WDN topology, subsequent to the detachments of failed elements, is combined with pressure-driven analysis. The methodology is demonstrated on a real water distribution network. Results show that, besides the failures causing the detachment of reservoirs, tanks, or pumps, there are other different topological modifications which may cause severe WDN service disruptions. Such information is of direct relevance to support planning asset enhancement works and improve the preparedness to extreme events.

  16. Proof test diagrams for Zerodur glass-ceramic

    NASA Technical Reports Server (NTRS)

    Tucker, D. S.

    1991-01-01

    Proof test diagrams for Zerodur glass-ceramics are calculated from available fracture mechanics data. It is shown that the environment has a large effect on minimum time-to-failure as predicted by proof test diagrams.

  17. Using Bayesian influence diagrams to assess organizational performance in 4 California county health departments, April-July 2009.

    PubMed

    Comfort, Louise K; Scheinert, Steve; Yeo, Jungwon; Schuh, Russell; Duran, Luis; Potter, Margaret A

    2013-01-01

    A Bayesian influence diagram is used to analyze interactions among operational units of county health departments. This diagram, developed using Bayesian network analysis, represents a novel method of analyzing the internal performance of county health departments that were operating under the simultaneous constraints of budget cuts and increased demand for services during the H1N1 threat in California, April-July 2009. This analysis reveals the interactions among internal organizational units that degrade performance under stress or, conversely, enable a county health department to manage heavy demands effectively.

  18. Common-Cause Failure Treatment in Event Assessment: Basis for a Proposed New Model

    SciTech Connect

    Dana Kelly; Song-Hua Shen; Gary DeMoss; Kevin Coyne; Don Marksberry

    2010-06-01

    Event assessment is an application of probabilistic risk assessment in which observed equipment failures and outages are mapped into the risk model to obtain a numerical estimate of the event’s risk significance. In this paper, we focus on retrospective assessments to estimate the risk significance of degraded conditions such as equipment failure accompanied by a deficiency in a process such as maintenance practices. In modeling such events, the basic events in the risk model that are associated with observed failures and other off-normal situations are typically configured to be failed, while those associated with observed successes and unchallenged components are assumed capable of failing, typically with their baseline probabilities. This is referred to as the failure memory approach to event assessment. The conditioning of common-cause failure probabilities for the common cause component group associated with the observed component failure is particularly important, as it is insufficient to simply leave these probabilities at their baseline values, and doing so may result in a significant underestimate of risk significance for the event. Past work in this area has focused on the mathematics of the adjustment. In this paper, we review the Basic Parameter Model for common-cause failure, which underlies most current risk modelling, discuss the limitations of this model with respect to event assessment, and introduce a proposed new framework for common-cause failure, which uses a Bayesian network to model underlying causes of failure, and which has the potential to overcome the limitations of the Basic Parameter Model with respect to event assessment.

  19. Patient-centered needs assessment: rationale for a psychometric measure for assessing needs in heart failure.

    PubMed

    Davidson, Patricia; Cockburn, Jill; Daly, John; Sanson Fisher, Rob

    2004-01-01

    Determining an individual's unique perspective of an illness experience remains a challenge for clinicians, administrators, and researchers. A range of concepts and psychometric measures have been developed and evaluated to capture this information. These include patient satisfaction, quality of life, and utility measures. Needs assessment as a tool for evaluating perceptions of health status and determining patient satisfaction and treatment plans has been explored in oncology. Studies have demonstrated that a high proportion of patients have unmet needs in relation to activities of daily living, information sources, and comfort. Heart failure (HF), a condition with significant individual and societal burden, mirrors the illness of experience of cancer, as individuals process issues related to prognosis, treatment regimens, and decreased functional status. A needs-based assessment of health status, expectations, and perceptions is patient-centered and has the capacity to not only evaluate current health status but also plan and project care plans. Needs assessment is a dynamic construct rather than a point in time consistent with other assessment modalities, such as quality of life. Multidimensional needs assessment allows for planning and projection of needs, not only on an individual but also a population basis. Implicit in the exploration of needs is an expectation of level of care to be provided, from both the provider and recipient of care. In many instances a misalignment may exist between services and resources available to the individual. This article seeks to provide a theoretical justification for the development of a needs assessment instrument for patients with HF and to discuss the rationale of this method of assessment to create better alignment and resources with patients needs and expectations.

  20. Failure assessment techniques to ensure shipping container integrity

    SciTech Connect

    McConnell, P.

    1986-02-01

    This report discusses several methodologies which may be used to ensure the structural integrity of containment systems to be used for the transport and storage of high-level radioactive substances. For economic reasons, shipping containers constructed of ferritic materials are being considered for manufacture by vendors in the US and Europe. Ferritic show an inherent transition from a ductile, high energy failure mode to a brittle, low energy fracture mode with decreasing temperature. Therefore, formal consideration of means by which to avoid unstable brittle fracture is necessary prior to the licensing of ferritic casks. It is suggested that failure of a shipping container wall be defined as occurring when a flaw extends through the outer wall of the containment system. Crack initiation which may lead to unstable brittle crack growth should therefore be prevented. It is suggested that a fundamental linear elastic fracture mechanics (lefm) approach be adopted on a case-by-case basis, applied perhaps by means of appropriate modifications to ASMA Section III or Section XI. A lefm analysis requires information concerning service temperatures, loading rates, flaw sizes, and applied stresses. Tentative judgments regarding these parameters for typical shipping containers have been made.

  1. Acute Heart Failure Registry: Risk Assessment Model in Decompensated Heart Failure

    PubMed Central

    Delgado, Anne; Rodrigues, Bruno; Nunes, Sara; Baptista, Rui; Marmelo, Bruno; Moreira, Davide; Gama, Pedro; Nunes, Luís; Santos, Oliveira; Cabral, Costa

    2016-01-01

    Background Heart failure (HF) is a highly prevalent syndrome. Although the long-term prognostic factors have been identified in chronic HF, this information is scarcer with respect to patients with acute HF. despite available data in the literature on long-term prognostic factors in chronic HF, data on acute HF patients are more scarce. Objectives To develop a predictor of unfavorable prognostic events in patients hospitalized for acute HF syndromes, and to characterize a group at higher risk regarding their clinical characteristics, treatment and outcomes. Methods cohort study of 600 patients admitted for acute HF, defined according to the European Society of Cardiology criteria. Primary endpoint for score derivation was defined as all-cause mortality and / or rehospitalization for HF at 12 months. For score validation, the following endpoints were used: all-cause mortality and / or readmission for HF at 6, 12 and 24 months. The exclusion criteria were: high output HF; patients with acute myocardial infraction, acute myocarditis, infectious endocarditis, pulmonary infection, pulmonary artery hypertension and severe mitral stenosis. Results 505 patients were included, and prognostic predicting factors at 12 months were identified. One or two points were assigned according to the odds ratio (OR) obtained (p < 0.05). After the total score value was determined, a 4-point cut-off was determined for each ROC curve at 12 months. Two groups were formed according to the number of points, group A < 4 points, and group B = 4 points. Group B was composed of older patients, with higher number of comorbidities and predictors of the combined endpoint at 6, 12 and 24 months, as linearly represented in the survival curves (Log rank). Conclusions This risk score enabled the identification of a group with worse prognosis at 12 months.

  2. A Critical Assessment of Ages Derived Using Pre-Main-Sequence Isochrones in Colour-Magnitude Diagrams

    NASA Astrophysics Data System (ADS)

    Bell, Cameron P. M.

    2012-11-01

    In this thesis a critical assessment of the ages derived using theoretical pre-main-sequence (pre-MS) stellar evolutionary models is presented by comparing the predictions to the low-mass pre-MS population of 14 young star-forming regions (SFRs) in colour-magnitude diagrams (CMDs). Deriving pre-MS ages requires precise distances and estimates of the reddening. Therefore, the main-sequence (MS) members of the SFRs have been used to derive a self-consistent set of statistically robust ages, distances and reddenings with associated uncertainties using a maximum-likelihood fitting statistic and MS evolutionary models. A photometric method for de-reddening individual stars - known as the Q-method - in regions where the extinction is spatially variable has been updated and is presented. The effects of both the model dependency and the SFR composition on these derived parameters are also discussed. The problem of calibrating photometric observations of red pre-MS stars is examined and it is shown that using observations of MS stars to transform the data into a standard photometric system can introduce significant errors in the position of the pre-MS locus in CMD space. Hence, it is crucial that precise photometric studies - especially of pre-MS objects - be carried out in the natural photometric system of the observations. This therefore requires a robust model of the system responses for the instrument used, and thus the calculated responses for the Wide-Field Camera on the Isaac Newton Telescope are presented. These system responses have been tested using standard star observations and have been shown to be a good representation of the photometric system. A benchmark test for the pre-MS evolutionary models is performed by comparing them to a set of well-calibrated CMDs of the Pleiades in the wavelength regime 0.4-2.5 μm. The masses predicted by these models are also tested against dynamical masses using a sample of MS binaries by calculating the system magnitude in a

  3. A novel risk assessment method for landfill slope failure: Case study application for Bhalswa Dumpsite, India.

    PubMed

    Jahanfar, Ali; Amirmojahedi, Mohsen; Gharabaghi, Bahram; Dubey, Brajesh; McBean, Edward; Kumar, Dinesh

    2017-03-01

    Rapid population growth of major urban centres in many developing countries has created massive landfills with extraordinary heights and steep side-slopes, which are frequently surrounded by illegal low-income residential settlements developed too close to landfills. These extraordinary landfills are facing high risks of catastrophic failure with potentially large numbers of fatalities. This study presents a novel method for risk assessment of landfill slope failure, using probabilistic analysis of potential failure scenarios and associated fatalities. The conceptual framework of the method includes selecting appropriate statistical distributions for the municipal solid waste (MSW) material shear strength and rheological properties for potential failure scenario analysis. The MSW material properties for a given scenario is then used to analyse the probability of slope failure and the resulting run-out length to calculate the potential risk of fatalities. In comparison with existing methods, which are solely based on the probability of slope failure, this method provides a more accurate estimate of the risk of fatalities associated with a given landfill slope failure. The application of the new risk assessment method is demonstrated with a case study for a landfill located within a heavily populated area of New Delhi, India.

  4. Development and validation of a questionnaire to assess fear of kidney failure following living donation.

    PubMed

    Rodrigue, James R; Fleishman, Aaron; Vishnevsky, Tanya; Whiting, James; Vella, John P; Garrison, Krista; Moore, Deonna; Kayler, Liise; Baliga, Prabhakar; Chavin, Kenneth D; Karp, Seth; Mandelbrot, Didier A

    2014-06-01

    Living kidney donors (LKDs) may feel more anxious about kidney failure now that they have only one kidney and the security of a second kidney is gone. The aim of this cross-sectional study was to develop and empirically validate a self-report scale for assessing fear of kidney failure in former LKDs. Participants were 364 former LKDs within the past 10 years at five US transplant centers and 219 healthy nondonor controls recruited through Mechanical Turk who completed several questionnaires. Analyses revealed a unidimensional factor structure, excellent internal consistency (α = 0.88), and good convergent validity for the Fear of Kidney Failure questionnaire. Only 13% of former donors reported moderate to high fear of kidney failure. Nonwhite race (OR = 2.9, P = 0.01), genetic relationship with the recipient (OR = 2.46, P = 0.04), and low satisfaction with the donation experience (OR = 0.49, P = 0.002) were significant predictors of higher fear of kidney failure. We conclude that while mild anxiety about kidney failure is common, high anxiety about future renal failure among former LKDs is uncommon. The Fear of Kidney Failure questionnaire is reliable, valid, and easy to use in the clinical setting.

  5. A Probabilistic Assessment of Failure for Air Force Building Systems

    DTIC Science & Technology

    2015-03-26

    desired end state for the community is an enterprise-wide asset management framework which can objectively assess an asset’s condition state and lead to...Department of Systems and Engineering Management Graduate School of Engineering and Management Air Force Institute of Technology Air University Air...Education and Training Command In Partial Fulfillment of the Requirements for the Degree of Master of Science in Engineering Management

  6. Lumbar Transpedicular Implant Failure: A Clinical and Surgical Challenge and Its Radiological Assessment

    PubMed Central

    Ali, Abdel Mohsen Arafa

    2014-01-01

    Study Design It is a multicenter, controlled case study review of a big scale of pedicle-screw procedures from January 2000 to June 2010. The outcomes were compared to those with no implant failure. Purpose The purpose of this study was to review retrospectively the outcome of 100 patients with implant failure in comparison to 100 control-patients, and to study the causes of failure and its prevention. Overview of Literature Transpedicular fixation is associated with risks of hardware failure, such as screw/rod breakage and/or loosening at the screw-rod interface and difficulties in the system assembly, which remain a significant clinical problem. Removal or revision of the spinal hardware is often required. Methods Two hundred patients (88 women, 112 men) were divided into 2 major groups, with 100 patients in group I (implant failure group G1) and 100 patients in group II (successful fusion, control group G2). We subdivided the study groups into two subgroups: subgroup a (single-level instrumented group) and subgroup b (multilevel instrumented group). The implant status was assessed based on intraoperative and follow-up radiographs. Results Implant failure in general was present in 36% in G1a, and in 64% in G1b, and types of implant failure included screw fracture (34%), rod fracture (24%), rod loosening (22%), screw loosening (16%), and failure of both rod and screw (4%). Most of the failures (90%) occurred within 6 months after surgery, with no reported cases 1 year postoperatively. Conclusions We tried to address the problem and study the causes of failure, and proposed solutions for its prevention. PMID:24967042

  7. System Reliability Assessment for a Rock Tunnel with Multiple Failure Modes

    NASA Astrophysics Data System (ADS)

    Lü, Qing; Chan, Chin Loong; Low, Bak Kong

    2013-07-01

    This paper presents a practical procedure for assessing the system reliability of a rock tunnel. Three failure modes, namely, inadequate support capacity, excessive tunnel convergence, and insufficient rockbolt length, are considered and investigated using a deterministic model of ground-support interaction analysis based on the convergence-confinement method (CCM). The failure probability of each failure mode is evaluated from the first-order reliability method (FORM) and the response surface method (RSM) via an iterative procedure. The system failure probability bounds are estimated using the bimodal bounds approach suggested by Ditlevsen (1979), based on the reliability index and design point inferred from the FORM. The proposed approach is illustrated with an example of a circular rock tunnel. The computed system failure probability bounds compare favorably with those generated from Monte Carlo simulations. The results show that the relative importance of different failure modes to the system reliability of the tunnel mainly depends on the timing of support installation relative to the advancing tunnel face. It is also shown that reliability indices based on the second-order reliability method (SORM) can be used to achieve more accurate bounds on the system failure probability for nonlinear limit state surfaces. The system reliability-based design for shotcrete thickness is also demonstrated.

  8. Application of ISO22000 and Failure Mode and Effect Analysis (fmea) for Industrial Processing of Poultry Products

    NASA Astrophysics Data System (ADS)

    Varzakas, Theodoros H.; Arvanitoyannis, Ioannis S.

    Failure Mode and Effect Analysis (FMEA) model has been applied for the risk assessment of poultry slaughtering and manufacturing. In this work comparison of ISO22000 analysis with HACCP is carried out over poultry slaughtering, processing and packaging. Critical Control points and Prerequisite programs (PrPs) have been identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram and fishbone diagram).

  9. When Summative Computer-Aided Assessments Go Wrong: Disaster Recovery after a Major Failure

    ERIC Educational Resources Information Center

    Harwood, Ian

    2005-01-01

    This case study outlines the events of a recent summative computer-aided assessment (CAA) failure involving 280 first-year undergraduate students. Post-test analysis found that the central server had become unexpectedly overloaded, thereby causing the CAA to be abandoned. Practical advice on just what to do in the event of a summative CAA failure…

  10. 30 CFR 1218.40 - Assessments for incorrect or late reports and failure to report.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Indian oil and gas leases. (c) For purpose of assessments discussed in this section, a report is defined... failure to report. 1218.40 Section 1218.40 Mineral Resources OFFICE OF NATURAL RESOURCES REVENUE, DEPARTMENT OF THE INTERIOR NATURAL RESOURCES REVENUE COLLECTION OF ROYALTIES, RENTALS, BONUSES, AND...

  11. ANALYSIS OF SEQUENTIAL FAILURES FOR ASSESSMENT OF RELIABILITY AND SAFETY OF MANUFACTURING SYSTEMS. (R828541)

    EPA Science Inventory

    Assessment of reliability and safety of a manufacturing system with sequential failures is an important issue in industry, since the reliability and safety of the system depend not only on all failed states of system components, but also on the sequence of occurrences of those...

  12. Assessing performance and validating finite element simulations using probabilistic knowledge

    SciTech Connect

    Dolin, Ronald M.; Rodriguez, E. A.

    2002-01-01

    Two probabilistic approaches for assessing performance are presented. The first approach assesses probability of failure by simultaneously modeling all likely events. The probability each event causes failure along with the event's likelihood of occurrence contribute to the overall probability of failure. The second assessment method is based on stochastic sampling using an influence diagram. Latin-hypercube sampling is used to stochastically assess events. The overall probability of failure is taken as the maximum probability of failure of all the events. The Likelihood of Occurrence simulation suggests failure does not occur while the Stochastic Sampling approach predicts failure. The Likelihood of Occurrence results are used to validate finite element predictions.

  13. Caution: Venn Diagrams Ahead!

    ERIC Educational Resources Information Center

    Kimmins, Dovie L.; Winters, J. Jeremy

    2015-01-01

    Two perspectives of the term "Venn diagram" reflect the typical differences in the uses of Venn diagrams in the subject areas of mathematics and language arts. These differences are subtle; nevertheless, they can potentially be confusing. In language arts, the circles in a Venn diagram typically represent things that can be compared and…

  14. An improved approach for flight readiness certification: Methodology for failure risk assessment and application examples, volume 1

    NASA Technical Reports Server (NTRS)

    Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

    1992-01-01

    An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with engineering analysis to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which engineering analysis models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. Conventional engineering analysis models currently employed for design of failure prediction are used in this methodology. The PFA methodology is described and examples of its application are presented. Conventional approaches to failure risk evaluation for spaceflight systems are discussed, and the rationale for the approach taken in the PFA methodology is presented. The statistical methods, engineering models, and computer software used in fatigue failure mode applications are thoroughly documented.

  15. An improved approach for flight readiness certification: Methodology for failure risk assessment and application examples. Volume 2: Software documentation

    NASA Technical Reports Server (NTRS)

    Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

    1992-01-01

    An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with engineering analysis to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which engineering analysis models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes, These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. Conventional engineering analysis models currently employed for design of failure prediction are used in this methodology. The PFA methodology is described and examples of its application are presented. Conventional approaches to failure risk evaluation for spaceflight systems are discussed, and the rationale for the approach taken in the PFA methodology is presented. The statistical methods, engineering models, and computer software used in fatigue failure mode applications are thoroughly documented.

  16. Performance improvement through proactive risk assessment: Using failure modes and effects analysis

    PubMed Central

    Yarmohammadian, Mohammad Hossein; Abadi, Tahereh Naseri Boori; Tofighi, Shahram; Esfahani, Sekine Saghaeiannejad

    2014-01-01

    Introduction: Cognizance of any error-prone professional activities has a great impact on the continuity of professional organizations in the competitive atmosphere, particularly in health care industry where every second has critical value in patients’ life saving. Considering invaluable functions of medical record department — as legal document and continuity of health care — “failure mode and effects analysis (FMEA)” utilized to identify the ways a process can fail, and how it can be made safer. Materials and Methods: The structured approach involved assembling a team of experts, employing a trained facilitator, introducing the rating scales and process during team orientation and collectively scoring failure modes. The probability of the failure-effect combination was related to the frequency of occurrence, potential severity, and likelihood of detection before causing any harm to the staff or patients. Frequency, severity and detectability were each given a score from 1 to 10. Risk priority numbers were calculated. Results: In total 56 failure modes were identified and in subsets of Medical Record Department including admission unit dividing emergency, outpatient and inpatient classes, statististic, health data organizing and data processing and Medical Coding units. Although most failure modes were classified as a high risk group, limited resources were, as an impediment to implement recommended actions at the same time. Conclusion: Proactive risk assessment methods, such as FMEA enable health care administrators to identify where and what safeguards are needed to protect against a bad outcome even when an error does occur. PMID:25013821

  17. Assessment of current structural design methodology for high-temperature reactors based on failure tests

    SciTech Connect

    Corum, J.M.; Sartory, W.K.

    1985-01-01

    A mature design methodology, consisting of inelastic analysis methods, provided in Department of Energy guidelines, and failure criteria, contained in ASME Code Case N-47, exists in the United States for high-temperature reactor components. The objective of this paper is to assess the adequacy of this overall methodology by comparing predicted inelastic deformations and lifetimes with observed results from structural failure tests and from an actual service failure. Comparisons are presented for three types of structural situations: (1) nozzle-to-spherical shell specimens, where stresses at structural discontinuities lead to cracking, (2) welded structures, where metallurgical discontinuities play a key role in failures, and (3) thermal shock loadings of cylinders and pipes, where thermal discontinuities can lead to failure. The comparison between predicted and measured inelastic responses are generally reasonalbly good; quantities are sometimes overpredicted somewhat, and, sometimes underpredicted. However, even seemingly small discrepancies can have a significant effect on structural life, and lifetimes are not always as closely predicted. For a few cases, the lifetimes are substantially overpredicted, which raises questions regarding the adequacy of existing design margins.

  18. Phase Equilibria Diagrams Database

    National Institute of Standards and Technology Data Gateway

    SRD 31 NIST/ACerS Phase Equilibria Diagrams Database (PC database for purchase)   The Phase Equilibria Diagrams Database contains commentaries and more than 21,000 diagrams for non-organic systems, including those published in all 21 hard-copy volumes produced as part of the ACerS-NIST Phase Equilibria Diagrams Program (formerly titled Phase Diagrams for Ceramists): Volumes I through XIV (blue books); Annuals 91, 92, 93; High Tc Superconductors I & II; Zirconium & Zirconia Systems; and Electronic Ceramics I. Materials covered include oxides as well as non-oxide systems such as chalcogenides and pnictides, phosphates, salt systems, and mixed systems of these classes.

  19. New medicinal products for chronic heart failure: advances in clinical trial design and efficacy assessment.

    PubMed

    Cowie, Martin R; Filippatos, Gerasimos S; Alonso Garcia, Maria de Los Angeles; Anker, Stefan D; Baczynska, Anna; Bloomfield, Daniel M; Borentain, Maria; Bruins Slot, Karsten; Cronin, Maureen; Doevendans, Pieter A; El-Gazayerly, Amany; Gimpelewicz, Claudio; Honarpour, Narimon; Janmohamed, Salim; Janssen, Heidi; Kim, Albert M; Lautsch, Dominik; Laws, Ian; Lefkowitz, Martin; Lopez-Sendon, Jose; Lyon, Alexander R; Malik, Fady I; McMurray, John J V; Metra, Marco; Figueroa Perez, Santiago; Pfeffer, Marc A; Pocock, Stuart J; Ponikowski, Piotr; Prasad, Krishna; Richard-Lordereau, Isabelle; Roessig, Lothar; Rosano, Giuseppe M C; Sherman, Warren; Stough, Wendy Gattis; Swedberg, Karl; Tyl, Benoit; Zannad, Faiez; Boulton, Caroline; De Graeff, Pieter

    2017-03-27

    Despite the availability of a number of different classes of therapeutic agents with proven efficacy in heart failure, the clinical course of heart failure patients is characterized by a reduction in life expectancy, a progressive decline in health-related quality of life and functional status, as well as a high risk of hospitalization. New approaches are needed to address the unmet medical needs of this patient population. The European Medicines Agency (EMA) is undertaking a revision of its Guideline on Clinical Investigation of Medicinal Products for the Treatment of Chronic Heart Failure. The draft version of the Guideline was released for public consultation in January 2016. The Cardiovascular Round Table of the European Society of Cardiology (ESC), in partnership with the Heart Failure Association of the ESC, convened a dedicated two-day workshop to discuss three main topic areas of major interest in the field and addressed in this draft EMA guideline: (i) assessment of efficacy (i.e. endpoint selection and statistical analysis); (ii) clinical trial design (i.e. issues pertaining to patient population, optimal medical therapy, run-in period); and (iii) research approaches for testing novel therapeutic principles (i.e. cell therapy). This paper summarizes the key outputs from the workshop, reviews areas of expert consensus, and identifies gaps that require further research or discussion. Collaboration between regulators, industry, clinical trialists, cardiologists, health technology assessment bodies, payers, and patient organizations is critical to address the ongoing challenge of heart failure and to ensure the development and market access of new therapeutics in a scientifically robust, practical and safe way.

  20. The importance of assessing nutritional status in elderly patients with heart failure.

    PubMed

    Sargento, Luis; Longo, Susana; Lousada, Nuno; dos Reis, Roberto Palma

    2014-06-01

    Heart failure (HF) is a syndrome characterized by high morbidity and mortality, despite advances in medical and device therapy that have significantly improved survival. The outcome of HF in elderly patients results from a combination of biological, functional, psychological, and environmental factors, one of which is nutritional status. Malnutrition, as well as HF, is frequently present with aging. Early detection might lead to earlier intervention. It is our goal to review the importance of nutritional status in elderly patients with HF, as well as tools for assessing it. We also propose a simple decision algorithm for the nutritional assessment of elderly patients with HF.

  1. Assessment of compressive failure process of cortical bone materials using damage-based model.

    PubMed

    Ng, Theng Pin; R Koloor, S S; Djuansjah, J R P; Abdul Kadir, M R

    2017-02-01

    The main failure factors of cortical bone are aging or osteoporosis, accident and high energy trauma or physiological activities. However, the mechanism of damage evolution coupled with yield criterion is considered as one of the unclear subjects in failure analysis of cortical bone materials. Therefore, this study attempts to assess the structural response and progressive failure process of cortical bone using a brittle damaged plasticity model. For this reason, several compressive tests are performed on cortical bone specimens made of bovine femur, in order to obtain the structural response and mechanical properties of the material. Complementary finite element (FE) model of the sample and test is prepared to simulate the elastic-to-damage behavior of the cortical bone using the brittle damaged plasticity model. The FE model is validated in a comparative method using the predicted and measured structural response as load-compressive displacement through simulation and experiment. FE results indicated that the compressive damage initiated and propagated at central region where maximum equivalent plastic strain is computed, which coincided with the degradation of structural compressive stiffness followed by a vast amount of strain energy dissipation. The parameter of compressive damage rate, which is a function dependent on damage parameter and the plastic strain is examined for different rates. Results show that considering a similar rate to the initial slope of the damage parameter in the experiment would give a better sense for prediction of compressive failure.

  2. Assessment of dune failure along the Dutch coast using a fully probabilistic approach

    NASA Astrophysics Data System (ADS)

    den Heijer, C.(Kees); Baart, Fedor; van Koningsveld, Mark

    2012-03-01

    This paper describes an investigation into the added value of a fully probabilistic approach to dune resilience assessment over the currently applied deterministic and semi-probabilistic approaches. The method is applied to the Dutch coast but is generically applicable, provided of course the sufficient availability of data. The DUROS+ model in its most basic form was used to quantitatively assess dune resilience. The Monte Carlo method was used for the probabilistic investigation. Important research questions were (1) where can the DUROS+ model in combination with the fully probabilistic approach be applied along the Dutch coast? and (2) what is the alongshore variability of failure probability using this probabilistic approach? The main conclusion of the work presented in this paper is that the fully probabilistic approach provides valuable added insight with respect to the actual failure probability of transects. At the same time it is noted that the current dune erosion model in its most basic form is not able to cover all of the Dutch coast. Reasons lie in the availability of sufficient quality boundary conditions, applicability limits associated with model assumptions and insufficient quality coastal profile information. To extend the coverage of the analysis of failure probabilities along the Dutch coast it is recommended (1) to involve more process-based model concepts that can cope with the situations DUROS+ cannot, and (2) to expand currently available data on boundary conditions.

  3. Use of Minimal Residual Disease Assessment to Redefine Induction Failure in Pediatric Acute Lymphoblastic Leukemia.

    PubMed

    O'Connor, David; Moorman, Anthony V; Wade, Rachel; Hancock, Jeremy; Tan, Ronald M R; Bartram, Jack; Moppett, John; Schwab, Claire; Patrick, Katharine; Harrison, Christine J; Hough, Rachael; Goulden, Nick; Vora, Ajay; Samarasinghe, Sujith

    2017-02-20

    Purpose Our aim was to determine the role of end-of-induction (EOI) minimal residual disease (MRD) assessment in the identification and stratification of induction failure in patients with pediatric acute lymphoblastic leukemia (ALL) and to identify genetic abnormalities that drive disease in these patients. Patients and Methods Analysis included 3,113 patients who were treated in the Medical Research Council UKALL2003 multicenter randomized trial (NCT00222612) between 2003 and 2011. MRD was measured by using standardized real-time quantitative PCR. Median follow-up was 5 years 9 months. Results Fifty-nine patients (1.9%) had morphologic induction failure with 5-year event-free survival (EFS) of 50.7% (95% CI, 37.4 to 64.0) and 5-year overall survival of 57.7% (95% CI, 44.2 to 71.2). Of these, a small proportion of patients with M2 marrow (6 of 44) and a low EOI MRD level (< 0.01%) had 5-year EFS of 100%. Conversely, among patients with morphologic remission 2.3% (61 of 2,633) had high MRD (≥ 5%) and 5-year EFS of 47.0% (95% CI, 32.9 to 61.1), which was similar to those with morphologic induction failure. Redefining induction failure to include morphologic induction failure and/or MRD ≥ 5% identified 3.9% (120 of 3,133 patients) of the trial cohort with 5-year EFS of 48.0% (95% CI, 39.3 to 58.6). Induction failure (morphologic or MRD ≥ 5%) occurred most frequently in T-ALL (10.1%; 39 of 386 T-ALL cases) and B-other ALL, that is, lacking established chromosomal abnormalities (5.6%; 43 of 772 B-other cases). Genetic testing within the B-other group revealed the presence of PDGFRB gene fusions, particularly EBF1-PDGFRB, in almost one third of B-other ALL cases. Conclusion Integration of EOI MRD level with morphology identifies induction failure more precisely than morphology alone. Prevalence of EBF1-PDGFRB fusions in this group highlights the importance of genetic screening to identify abnormalities that may be targets for novel agents.

  4. Sleep disturbances in caregivers of patients with end-stage congestive heart failure: Part II--assess and intervene.

    PubMed

    Rausch, Sarah M; Baker, Kathy; Boonmee, Junyanee

    2007-01-01

    Sleep disturbances in caregivers of patients with congestive heart failure is common. The consequences of sleep disturbances are dire and have potential to seriously impact caregiver health and patient outcomes. Therefore, it is imperative that the health care team, especially nurses, assess and intervene. Basic assessment of caregiver sleep disturbance can be quick and simple and can be performed while assessing the congestive heart failure patient's health. If a more complex sleep disorder is suspected, other assessments can be conducted if time and money permit. The benefits to properly assessing sleep disturbance and subsequent treatment far outweigh the minimal time spent by the health care team or caregiver.

  5. 76 FR 70768 - Common-Cause Failure Analysis in Event and Condition Assessment: Guidance and Research, Draft...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... From the Federal Register Online via the Government Publishing Office NUCLEAR REGULATORY COMMISSION Common-Cause Failure Analysis in Event and Condition Assessment: Guidance and Research, Draft Report for Comment; Correction AGENCY: Nuclear Regulatory Commission. ACTION: Draft NUREG; request...

  6. Hertzsprung-Russell Diagram

    NASA Astrophysics Data System (ADS)

    Chiosi, C.; Murdin, P.

    2000-11-01

    The Hertzsprung-Russell diagram (HR-diagram), pioneered independently by EJNAR HERTZSPRUNG and HENRY NORRIS RUSSELL, is a plot of the star luminosity versus the surface temperature. It stems from the basic relation for an object emitting thermal radiation as a black body: ...

  7. Assessment of Three Finite Element Approaches for Modeling the Ballistic Impact Failure of Metal Plates

    NASA Astrophysics Data System (ADS)

    Mansur, Ali; Nganbe, Michel

    2015-03-01

    The ballistic impact was numerically modeled for AISI 450 steel struck by a 17.3 g ogive nose WC-Co projectile using Abaqus/Explicit. The model was validated using experimental results and data for different projectiles and metal targets. The Abaqus ductile-shear, local principal strain to fracture, and absorbed strain energy at failure criteria were investigated. Due to the highly dynamic nature of ballistic impacts, the absorbed strain energy approach posed serious challenges in estimating the effective deformation volume and yielded the largest critical plate thicknesses for through-thickness penetration (failure). In contrast, the principal strain criterion yielded the lowest critical thicknesses and provided the best agreement with experimental ballistic test data with errors between 0 and 30%. This better accuracy was due to early failure definition when the very first mesh at the target back side reached the strain to fracture, which compensated for the overall model overestimation. The ductile-shear criterion yielded intermediate results between those of the two comparative approaches. In contrast to the ductile-shear criterion, the principal strain criterion requires only basic data readily available for practically all materials. Therefore, it is a viable alternative for an initial assessment of the ballistic performance and pre-screening of a large number of new candidate materials as well as for supporting the development of novel armor systems.

  8. Risk assessment for Industrial Control Systems quantifying availability using mean failure cost (MFC)

    DOE PAGES

    Chen, Qian; Abercrombie, Robert K; Sheldon, Frederick T.

    2015-09-23

    Industrial Control Systems (ICS) are commonly used in industries such as oil and natural gas, transportation, electric, water and wastewater, chemical, pharmaceutical, pulp and paper, food and beverage, as well as discrete manufacturing (e.g., automotive, aerospace, and durable goods.) SCADA systems are generally used to control dispersed assets using centralized data acquisition and supervisory control. Originally, ICS implementations were susceptible primarily to local threats because most of their components were located in physically secure areas (i.e., ICS components were not connected to IT networks or systems). The trend toward integrating ICS systems with IT networks (e.g., efficiency and the Internetmore » of Things) provides significantly less isolation for ICS from the outside world thus creating greater risk due to external threats. Albeit, the availability of ICS/SCADA systems is critical to assuring safety, security and profitability. Such systems form the backbone of our national cyber-physical infrastructure. We extend the concept of mean failure cost (MFC) to address quantifying availability to harmonize well with ICS security risk assessment. This new measure is based on the classic formulation of Availability combined with Mean Failure Cost (MFC). The metric offers a computational basis to estimate the availability of a system in terms of the loss that each stakeholder stands to sustain as a result of security violations or breakdowns (e.g., deliberate malicious failures).« less

  9. Risk assessment for Industrial Control Systems quantifying availability using mean failure cost (MFC)

    SciTech Connect

    Chen, Qian; Abercrombie, Robert K; Sheldon, Frederick T.

    2015-09-23

    Industrial Control Systems (ICS) are commonly used in industries such as oil and natural gas, transportation, electric, water and wastewater, chemical, pharmaceutical, pulp and paper, food and beverage, as well as discrete manufacturing (e.g., automotive, aerospace, and durable goods.) SCADA systems are generally used to control dispersed assets using centralized data acquisition and supervisory control. Originally, ICS implementations were susceptible primarily to local threats because most of their components were located in physically secure areas (i.e., ICS components were not connected to IT networks or systems). The trend toward integrating ICS systems with IT networks (e.g., efficiency and the Internet of Things) provides significantly less isolation for ICS from the outside world thus creating greater risk due to external threats. Albeit, the availability of ICS/SCADA systems is critical to assuring safety, security and profitability. Such systems form the backbone of our national cyber-physical infrastructure. We extend the concept of mean failure cost (MFC) to address quantifying availability to harmonize well with ICS security risk assessment. This new measure is based on the classic formulation of Availability combined with Mean Failure Cost (MFC). The metric offers a computational basis to estimate the availability of a system in terms of the loss that each stakeholder stands to sustain as a result of security violations or breakdowns (e.g., deliberate malicious failures).

  10. A theoretical approach to assess microbial risks due to failures in drinking water systems.

    PubMed

    Westrell, T; Bergstedt, O; Stenström, T A; Ashbolt, N J

    2003-06-01

    A failure in treatment or in the distribution network of a surface water-works could have serious consequences due to the variable raw water quality in combination with an extended distribution. The aim of this study was to examine the theoretical impact of incidents in the drinking water system on the annual risk of infection in a population served by a large water treatment plant in Sweden. Reported incidents in the system were examined and a microbial risk assessment that included three pathogens, Cryptosporidium parvum, rotavirus and Campylobacter jejuni, was performed. The main risk incidents in water treatment were associated with sub-optimal particle removal or disinfection malfunction. Incidents in the distribution network included cross-connections and microbial pollution of reservoirs and local networks. The majority of the annual infections were likely to be due to pathogens passing treatment during normal operation and not due to failures, thus adding to the endemic rate. Among the model organisms, rotavirus caused the largest number of infections. Decentralised water treatment with membranes was also considered in which failures upstream fine-pored membranes would have little impact as long as the membranes were kept intact.

  11. The assessment of low probability containment failure modes using dynamic PRA

    NASA Astrophysics Data System (ADS)

    Brunett, Acacia Joann

    Although low probability containment failure modes in nuclear power plants may lead to large releases of radioactive material, these modes are typically crudely modeled in system level codes and have large associated uncertainties. Conventional risk assessment techniques (i.e. the fault-tree/event-tree methodology) are capable of accounting for these failure modes to some degree, however, they require the analyst to pre-specify the ordering of events, which can vary within the range of uncertainty of the phenomena. More recently, dynamic probabilistic risk assessment (DPRA) techniques have been developed which remove the dependency on the analyst. Through DPRA, it is now possible to perform a mechanistic and consistent analysis of low probability phenomena, with the timing of the possible events determined by the computational model simulating the reactor behavior. The purpose of this work is to utilize DPRA tools to assess low probability containment failure modes and the driving mechanisms. Particular focus is given to the risk-dominant containment failure modes considered in NUREG-1150, which has long been the standard for PRA techniques. More specifically, this work focuses on the low probability phenomena occurring during a station blackout (SBO) with late power recovery in the Zion Nuclear Power Plant, a Westinghouse pressurized water reactor (PWR). Subsequent to the major risk study performed in NUREG-1150, significant experimentation and modeling regarding the mechanisms driving containment failure modes have been performed. In light of this improved understanding, NUREG-1150 containment failure modes are reviewed in this work using the current state of knowledge. For some unresolved mechanisms, such as containment loading from high pressure melt ejection and combustion events, additional analyses are performed using the accident simulation tool MELCOR to explore the bounding containment loads for realistic scenarios. A dynamic treatment in the

  12. Inductively generating Euler diagrams.

    PubMed

    Stapleton, Gem; Rodgers, Peter; Howse, John; Zhang, Leishi

    2011-01-01

    Euler diagrams have a wide variety of uses, from information visualization to logical reasoning. In all of their application areas, the ability to automatically layout Euler diagrams brings considerable benefits. In this paper, we present a novel approach to Euler diagram generation. We develop certain graphs associated with Euler diagrams in order to allow curves to be added by finding cycles in these graphs. This permits us to build Euler diagrams inductively, adding one curve at a time. Our technique is adaptable, allowing the easy specification, and enforcement, of sets of well-formedness conditions; we present a series of results that identify properties of cycles that correspond to the well-formedness conditions. This improves upon other contributions toward the automated generation of Euler diagrams which implicitly assume some fixed set of well-formedness conditions must hold. In addition, unlike most of these other generation methods, our technique allows any abstract description to be drawn as an Euler diagram. To establish the utility of the approach, a prototype implementation has been developed.

  13. Assessing elderly patients with congestive heart failure via in-home interactive telecommunication.

    PubMed

    Jenkins, R L; McSweeney, M

    2001-01-01

    The efficacy of telemedicine technology was tested for equivalence of nursing assessment with chronic congestive heart failure (CHF) home care patients (N = 28). The equivalence of nurses' physical assessment findings was estimated using an innovative two-way, telemedicine audiovisual system. Nurses were randomly assigned to a method of client assessment: on-site (real time) or telemedicine (monitor time). Each assessment was performed within 10 minutes of each other. Assessment variables compared were auscultation of lung sounds, heart sounds, rate and rhythm, blood pressure, weight, edema, respiratory effort, and client's face, lip, and nail color. Eighteen physiological parameters were analyzed, using either the Wilcoxon signed ranks test or the McNemar test. Results indicate few significant differences between the assessments of the real time and monitor time nurses. The monitor nurse was more likely to claim abnormality than the real nurse was when assessing the color of nails (p = .048). The real nurse picked up ankle edema (p = .024), pedal edema (p = .099), and inspiratory wheeze (p = .01) more frequently than did the monitor nurse. Kappa coefficients to determine the extent of agreement between nurse's assessments were significant. Nurses' comments were favorable, but they recommended altering the interview to elicit symptoms not easily observed by the monitor nurse such as diaphoresis. Exit interviews of the elderly patients revealed a favorable reaction to using the telemedicine monitor, citing a quick connection to a nurse and response to their concerns and questions. Both nurses and patients reported the need to have real nurse home visits along with telemedicine visits.

  14. Square Source Type Diagram

    NASA Astrophysics Data System (ADS)

    Aso, N.; Ohta, K.; Ide, S.

    2014-12-01

    Deformation in a small volume of earth interior is expressed by a symmetric moment tensor located on a point source. The tensor contains information of characteristic directions, source amplitude, and source types such as isotropic, double-couple, or compensated-linear-vector-dipole (CLVD). Although we often assume a double couple as the source type of an earthquake, significant non-double-couple component including isotropic component is often reported for induced earthquakes and volcanic earthquakes. For discussions on source types including double-couple and non-double-couple components, it is helpful to display them using some visual diagrams. Since the information of source type has two degrees of freedom, it can be displayed onto a two-dimensional flat plane. Although the diagram developed by Hudson et al. [1989] is popular, the trace corresponding to the mechanism combined by two mechanisms is not always a smooth line. To overcome this problem, Chapman and Leaney [2012] developed a new diagram. This diagram has an advantage that a straight line passing through the center corresponds to the mechanism obtained by a combination of an arbitrary mechanism and a double-couple [Tape and Tape, 2012], but this diagram has some difficulties in use. First, it is slightly difficult to produce the diagram because of its curved shape. Second, it is also difficult to read out the ratios among isotropic, double-couple, and CLVD components, which we want to obtain from the estimated moment tensors, because they do not appear directly on the horizontal or vertical axes. In the present study, we developed another new square diagram that overcomes the difficulties of previous diagrams. This diagram is an orthogonal system of isotropic and deviatoric axes, so it is easy to get the ratios among isotropic, double-couple, and CLVD components. Our diagram has another advantage that the probability density is obtained simply from the area within the diagram if the probability density

  15. Multinational assessment of accuracy of equations for predicting risk of kidney failure: a meta-analysis

    PubMed Central

    Tangri, Navdeep; Grams, Morgan E.; Levey, Andrew S.; Coresh, Josef; Appel, Lawrence; Astor, Brad C.; Chodick, Gabriel; Collins, Allan J.; Djurdjev, Ognjenka; Elley, C. Raina; Evans, Marie; Garg, Amit X.; Hallan, Stein I.; Inker, Lesley; Ito, Sadayoshi; Jee, Sun Ha; Kovesdy, Csaba P.; Kronenberg, Florian; Lambers Heerspink, Hiddo J.; Marks, Angharad; Nadkarni, Girish N.; Navaneethan, Sankar D.; Nelson, Robert G.; Titze, Stephanie; Sarnak, Mark J.; Stengel, Benedicte; Woodward, Mark; Iseki, Kunitoshi

    2016-01-01

    Importance Identifying patients at risk of chronic kidney disease (CKD) progression may facilitate more optimal nephrology care. Kidney failure risk equations (KFREs) were previously developed and validated in two Canadian cohorts. Validation in other regions and in CKD populations not under the care of a nephrologist is needed. Objective To evaluate the accuracy of the KFREs across different geographic regions and patient populations through individual-participant data meta-analysis. Data Sources Thirty-one cohorts, including 721,357 participants with CKD Stages 3–5 in over 30 countries spanning 4 continents, were studied. These cohorts collected data from 1982 through 2014. Study Selection Cohorts participating in the CKD Prognosis Consortium with data on end-stage renal disease. Data Extraction and Synthesis Data were obtained and statistical analyses were performed between July 2012 and June 2015. Using the risk factors from the original KFREs, cohort-specific hazard ratios were estimated, and combined in meta-analysis to form new “pooled” KFREs. Original and pooled equation performance was compared, and the need for regional calibration factors was assessed. Main Outcome and Measure Kidney failure (treatment by dialysis or kidney transplantation). Results During a median follow-up of 4 years, 23,829 cases of kidney failure were observed. The original KFREs achieved excellent discrimination (ability to differentiate those who developed kidney failure from those who did not) across all cohorts (overall C statistic, 0.90 (95% CI 0.89–0.92) at 2 years and 0.88 (95% CI 0.86–0.90) at 5 years); discrimination in subgroups by age, race, and diabetes status was similar. There was no improvement with the pooled equations. Calibration (the difference between observed and predicted risk) was adequate in North American cohorts, but the original KFREs overestimated risk in some non-North American cohorts. Addition of a calibration factor that lowered the baseline

  16. Aerobic exercise training intensity in patients with chronic heart failure: principles of assessment and prescription.

    PubMed

    Carvalho, Vitor Oliveira; Mezzani, Alessandro

    2011-02-01

    Chronic heart failure (CHF) is a significant cause of worldwide mortality and morbidity, whose clinical picture is characterized by exercise intolerance and impaired quality of life. Aerobic exercise training is a well-established nonpharmacological tool improving the CHF’s pathophysiological, clinical, and prognostic picture, and prescription of an adequate training intensity is crucial to obtain both exercise-induced benefits and a reasonable control of exercise-related risk. However, clarity is still lacking regarding the definition of exercise intensity domains and the lower and upper intensity limits of prescriptible aerobic exercise in CHF patients. The purpose of this review is to provide an update of the methods for the exercise intensity assessment and continuous aerobic training intensity prescription in the CHF population, furnishing indications useful for implementation of physical rehabilitation programs in these patients.

  17. Noninvasive assessment of right and left ventricular function in acute and chronic respiratory failure

    SciTech Connect

    Matthay, R.A.; Berger, H.J.

    1983-05-01

    This review evaluates noninvasive techniques for assessing cardiovascular performance in acute and chronic respiratory failure. Radiographic, radionuclide, and echocardiographic methods for determining ventricular volumes, right (RV) and left ventricular (LV) ejection fractions, and pulmonary artery pressure (PAP) are emphasized. These methods include plain chest radiography, radionuclide angiocardiography, thallium-201 myocardial imaging, and M mode and 2-dimensional echocardiography, which have recently been applied in patients to detect pulmonary artery hypertension (PAH), right ventricular enlargement, and occult ventricular performance abnormalities at rest or exercise. Moreover, radionuclide angiocardiography has proven useful in combination with hemodynamic measurements, for evaluating the short-and long-term cardiovascular effects of therapeutic agents, such as oxygen, digitalis, theophylline, beta-adrenergic agents, and vasodilators.

  18. Radionuclide noninvasive evaluation of heart failure beyond left ventricular function assessment.

    PubMed

    Flotats, Albert; Carrió, Ignasi

    2009-01-01

    The management of patients with heart failure (HF) is challenging and requires the integration of clinical skills and accurate ancillary tests for the correct diagnosis and estimation of individual prognosis. Although the basic characterization of patients with HF is supported primarily by echocardiographic assessment of the left ventricular function, other noninvasive imaging procedures are being developed, including those involved in the processes of myocardial perfusion, metabolism, cellular injury, intersticial dysregulation, and neurohormonal receptor function. Nuclear techniques for molecular imaging of the myocardium may provide valuable insights into the pathophysiology, severity, management (medical/mechanical/surgical), response to treatment, and prognosis of HF patients. This will permit individualized management decisions and hopefully facilitate better clinical outcomes for patients with HF.

  19. Risk assessment of turbine rotor failure using probabilistic ultrasonic non-destructive evaluations

    SciTech Connect

    Guan, Xuefei; Zhang, Jingdan; Zhou, S. Kevin; Rasselkorde, El Mahjoub; Abbasi, Waheed A.

    2014-02-18

    The study presents a method and application of risk assessment methodology for turbine rotor fatigue failure using probabilistic ultrasonic nondestructive evaluations. A rigorous probabilistic modeling for ultrasonic flaw sizing is developed by incorporating the model-assisted probability of detection, and the probability density function (PDF) of the actual flaw size is derived. Two general scenarios, namely the ultrasonic inspection with an identified flaw indication and the ultrasonic inspection without flaw indication, are considered in the derivation. To perform estimations for fatigue reliability and remaining useful life, uncertainties from ultrasonic flaw sizing and fatigue model parameters are systematically included and quantified. The model parameter PDF is estimated using Bayesian parameter estimation and actual fatigue testing data. The overall method is demonstrated using a realistic application of steam turbine rotor, and the risk analysis under given safety criteria is provided to support maintenance planning.

  20. Modeling of Electrical Cable Failure in a Dynamic Assessment of Fire Risk

    NASA Astrophysics Data System (ADS)

    Bucknor, Matthew D.

    complexity to existing cable failure techniques and tuned to empirical data can better approximate the temperature response of a cables located in tightly packed cable bundles. The new models also provide a way to determine the conditions insides a cable bundle which allows for separate treatment of cables on the interior of the bundle from cables on the exterior of the bundle. The results from the DET analysis show that the overall assessed probability of cable failure can be significantly reduced by more realistically accounting for the influence that the fire brigade has on a fire progression scenario. The shielding analysis results demonstrate a significant reduction in the temperature response of a shielded versus a non-shielded cable bundle; however the computational cost of using a fire progression model that can capture these effects may be prohibitive for performing DET analyses with currently available computational fluid dynamics models and computational resources.

  1. A Model for Assessment of Failure of LWR Fuel during an RIA

    SciTech Connect

    Liu, Wenfeng; Kazimi, Mujid S.

    2007-07-01

    This paper presents a model for Pellet-Cladding Mechanical Interaction (PCMI) failure of LWR fuel during an RIA. The model uses the J-integral as a driving parameter to characterize the failure potential during PCMI. The model is implemented in the FRAPTRAN code and is validated by CABRI and NSRR simulated RIA test data. Simulation of PWR and BWR conditions are conducted by FRAPTRAN to evaluate the fuel failure potential using this model. Model validation and simulation results are compared with the strain-based failure model of PNNL and the SED/CSED model of EPRI. Our fracture mechanics model has good capability to differentiate failure from non-failure cases. The results reveal significant effects of power pulse width: a wider pulse width generally increases the threshold for fuel failure. However, this effect is less obvious for highly corroded cladding. (authors)

  2. Relationship between Sequential Organ Failure Assessment (SOFA) and intra-abdominal pressure in intensive care unit

    PubMed Central

    de FREITAS, Gustavo Rocha Costa; da FONSECA-NETO, Olival Cirilo Lucena; PINHEIRO, Carla Larissa Fernandes; ARAÚJO, Luiz Clêiner; BARBOSA, Roberto Esmeraldo Nogueira; ALVES, Pedro

    2014-01-01

    Background Patients in the intensive care unit are at risk of developing intra-abdominal hypertension and abdominal compartment syndrome. Aim To describe the relation between Sequential Organ Failure Assessment (SOFA) vs. intra-abdominal pressure and the relation between SOFA and risk factors for intra-abdominal hypertension. Method In accordance with the recommendations of the World Society of the Abdominal Compartment Syndrome, the present study measured the intra-abdominal pressure of patients 24 h and 48 h after admission to the unit and calculated the SOFA after 24 h and 48 h. Data was collected over two-month period. Results No correlation was found between SOFA and intra-abdominal pressure. Seventy percent of the patients were men and the mean age was 44 years, 10% had been referred from general surgery (with a mean intra-abdominal pressure of 11) and 65% from neurosurgery (with a mean intra-abdominal of 6.7). Only three (7.5%) presented with intra-abdominal hypertension. The highest SOFA was 15 and the most frequent kind of organ failure was neurological, with a frequency of 77%. There was a strong correlation between the SOFA after 24 h and 48 h and peak respiratory pressure (ρ=0.43/p=0.01; ρ=0.39/p=0.02). Conclusion No correlation was found between SOFA and intra-abdominal pressure in the patients covered by the present study. However, it is possible in patients undergoing abdominal surgery or those with abdominal sepsis. Não houve correlação entre o SOFA e a pressão intra-abdominal nos pacientes aqui estudados; contudo, sinalizou ser possível em pacientes com operação abdominal ou naqueles com sepse abdominal. PMID:25626934

  3. Impulse-Momentum Diagrams

    ERIC Educational Resources Information Center

    Rosengrant, David

    2011-01-01

    Multiple representations are a valuable tool to help students learn and understand physics concepts. Furthermore, representations help students learn how to think and act like real scientists. These representations include: pictures, free-body diagrams, energy bar charts, electrical circuits, and, more recently, computer simulations and…

  4. Methods for the development and assessment of atrial fibrillation and heart failure dog models

    PubMed Central

    Urban, Jon F; Gerhart, Renee L; Krzeszak, Jason R; Leet, Corey R; Lentz, Linnea R; McClay, Carolyn B

    2011-01-01

    Objective To report Medtronic experiences with the development of animal models for atrial fibrillation (AF) and chronic heart failure (CHF) using high-rate pacing for AF and microemboli for CHF. Methods For the AF model, an atrial lead was attached to a Medtronic Synergy™ neurostimulator, which was programmed to stimulate at 50 Hz in an on-off duty cycle. Atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and N-terminal pro brain natriuretic peptide (NT-proBNP) were assayed at select time points. For CHF model, a serial injection of 90 µm polystyrene microspheres at 62,400 beads/mL (Polybead, Polysciences, Inc.) was performed to induce global ischemia, either with weekly monitoring and embolization schedule (group 1, n = 25) or with biweekly monitoring and emboliation schedule (group 2, n = 36 ). Echocardiograms were used along with ventriculograms and magnetic resonance imaging scans weekly to assess cardiac function and ANP, BNP and NT-proBNP were monitored. Results For the AF model, the days to sustained AF for four animals following surgery were 7, 25, 21 and 19, respectively; For the CHF model, the days to meet CHF endpoints were 116 in group 1 and 89 in group 2. For both AF and CHF models, NT-proBNP correlated well with the development of disease states. Conclusion Our experience for the development and assessment of AF and CHF dog models may help researchers who are in search for animal model for assessing the safety and efficacy of a device-based therapy. PMID:22783299

  5. Assessment and prevalence of pulmonary oedema in contemporary acute heart failure trials: a systematic review

    PubMed Central

    Platz, Elke; Jhund, Pardeep S.; Campbell, Ross T.; McMurray, John J.

    2015-01-01

    Aims Pulmonary oedema is a common and important finding in acute heart failure (AHF). We conducted a systematic review to describe the methods used to assess pulmonary oedema in recent randomized AHF trials and report its prevalence in these trials. Methods and results Of 23 AHF trials published between 2002 and 2013, six were excluded because they were very small or not randomized, or missing full-length publications. Of the remaining 17 (n = 200–7141) trials, six enrolled patients with HF and reduced ejection fraction (HF-REF) and 11, patients with both HF-REF and HF with preserved ejection fraction (HF-PEF). Pulmonary oedema was an essential inclusion criterion, in most trials, based upon findings on physical examination (‘rales’), radiographic criteria (‘signs of congestion’), or both. The prevalence of pulmonary oedema in HF-REF trials ranged from 75% to 83% and in combined HF-REF and HF-PEF trials from 51% to 100%. Five trials did not report the prevalence or extent of pulmonary oedema assessed by either clinical examination or chest x-ray. Improvement of pulmonary congestion with treatment was inconsistently reported and commonly grouped with other signs of congestion into a score. One trial suggested that patients with rales over >2/3 of the lung fields on admission were at higher risk of adverse outcomes than those without. Conclusion Although pulmonary oedema is a common finding in AHF, represents a therapeutic target, and may be of prognostic importance, recent trials used inconsistent criteria to define it, and did not consistently report its severity at baseline or its response to treatment. Consistent and ideally quantitative, methods for the assessment of pulmonary oedema in AHF trials are needed. PMID:26230356

  6. Software Tools for Lifetime Assessment of Thermal Barrier Coatings Part I — Thermal Ageing Failure and Thermal Fatigue Failure

    NASA Astrophysics Data System (ADS)

    Renusch, Daniel; Rudolphi, Mario; Schütze, Michael

    Thermal barrier coatings (TBCs) increase the service lifetime of specific components in, for example, gas turbines or airplane engines and allow higher operating temperatures to increase efficiency. Lifetime prediction models are therefore of both academic and applied interest; either to test new coatings or to determine operational conditions that can ensure a certain lifetime, for example 25,000 hr for gas turbines. Driven by these demands, the equations used in lifetime prediction have become more and more sophisticated and consequently are complicated to apply. A collection of software tools for lifetime assessment was therefore developed to provide an easy to use graphical user interface whilst incorporating the recent improvements in modeling equations. The Windows based software is compatible with other Windows applications, such as, Power Point, Excel, or Origin. Laboratory lifetime data from isothermal, thermal cyclic and/or burner rig testing can be loaded into the software for analysis and the program provides confidence limits and an accuracy assessment of the analysis model. The main purpose of the software tool is to predict TBC spallation for a given bond coat temperature, temperature gradient across the coating, and thermal cycle frequency.

  7. Probabilistic exposure assessment model to estimate aseptic-UHT product failure rate.

    PubMed

    Pujol, Laure; Albert, Isabelle; Magras, Catherine; Johnson, Nicholas Brian; Membré, Jeanne-Marie

    2015-01-02

    Aseptic-Ultra-High-Temperature (UHT) products are manufactured to be free of microorganisms capable of growing in the food at normal non-refrigerated conditions at which the food is likely to be held during manufacture, distribution and storage. Two important phases within the process are widely recognised as critical in controlling microbial contamination: the sterilisation steps and the following aseptic steps. Of the microbial hazards, the pathogen spore formers Clostridium botulinum and Bacillus cereus are deemed the most pertinent to be controlled. In addition, due to a relatively high thermal resistance, Geobacillus stearothermophilus spores are considered a concern for spoilage of low acid aseptic-UHT products. A probabilistic exposure assessment model has been developed in order to assess the aseptic-UHT product failure rate associated with these three bacteria. It was a Modular Process Risk Model, based on nine modules. They described: i) the microbial contamination introduced by the raw materials, either from the product (i.e. milk, cocoa and dextrose powders and water) or the packaging (i.e. bottle and sealing component), ii) the sterilisation processes, of either the product or the packaging material, iii) the possible recontamination during subsequent processing of both product and packaging. The Sterility Failure Rate (SFR) was defined as the sum of bottles contaminated for each batch, divided by the total number of bottles produced per process line run (10(6) batches simulated per process line). The SFR associated with the three bacteria was estimated at the last step of the process (i.e. after Module 9) but also after each module, allowing for the identification of modules, and responsible contamination pathways, with higher or lower intermediate SFR. The model contained 42 controlled settings associated with factory environment, process line or product formulation, and more than 55 probabilistic inputs corresponding to inputs with variability

  8. Assessing the Value-Added by the Environmental Testing Process with the Aide of Physics/Engineering of Failure Evaluations

    NASA Technical Reports Server (NTRS)

    Cornford, S.; Gibbel, M.

    1997-01-01

    NASA's Code QT Test Effectiveness Program is funding a series of applied research activities focused on utilizing the principles of physics and engineering of failure and those of engineering economics to assess and improve the value-added by the various validation and verification activities to organizations.

  9. Materials Degradation & Failure: Assessment of Structure and Properties. Resources in Technology.

    ERIC Educational Resources Information Center

    Technology Teacher, 1991

    1991-01-01

    This module provides information on materials destruction (through corrosion, oxidation, and degradation) and failure. A design brief includes objective, student challenge, resources, student outcomes, and quiz. (SK)

  10. A non-stationary earthquake probability assessment with the Mohr-Coulomb failure criterion

    NASA Astrophysics Data System (ADS)

    Wang, J. P.; Xu, Y.

    2015-10-01

    From theory to experience, earthquake probability associated with an active fault should be gradually increasing with time since the last event. In this paper, a new non-stationary earthquake assessment motivated/derived from the Mohr-Coulomb failure criterion is introduced. Different from other non-stationary earthquake analyses, the new model can more clearly define and calculate the stress states between two characteristic earthquakes. In addition to the model development and the algorithms, this paper also presents an example calculation to help explain and validate the new model. On the condition of best-estimate model parameters, the example calculation shows a 7.6 % probability for the Meishan fault in central Taiwan to induce a major earthquake in years 2015-2025, and if the earthquake does not occur by 2025, the earthquake probability will increase to 8 % in 2025-2035, which validates the new model that can calculate non-stationary earthquake probability as it should vary with time.

  11. Direct and indirect assessment of skeletal muscle blood flow in chronic congestive heart failure

    SciTech Connect

    LeJemtel, T.H.; Scortichini, D.; Katz, S.

    1988-09-09

    In patients with chronic congestive heart failure (CHF), skeletal muscle blood flow can be measured directly by the continuous thermodilution technique and by the xenon-133 clearance method. The continuous thermodilution technique requires retrograde catheterization of the femoral vein and, thus, cannot be repeated conveniently in patients during evaluation of pharmacologic interventions. The xenon-133 clearance, which requires only an intramuscular injection, allows repeated determination of skeletal muscle blood flow. In patients with severe CHF, a fixed capacity of the skeletal muscle vasculature to dilate appears to limit maximal exercise performance. Moreover, the changes in peak skeletal muscle blood flow noted during long-term administration of captopril, an angiotensin-converting enzyme inhibitor, appears to correlate with the changes in aerobic capacity. In patients with CHF, resting supine deep femoral vein oxygen content can be used as an indirect measurement of resting skeletal muscle blood flow. The absence of a steady state complicates the determination of peak skeletal muscle blood flow reached during graded bicycle or treadmill exercise in patients with chronic CHF. Indirect assessments of skeletal muscle blood flow and metabolism during exercise performed at submaximal work loads are currently developed in patients with chronic CHF.

  12. Symptom burden in heart failure: assessment, impact on outcomes, and management.

    PubMed

    Alpert, Craig M; Smith, Michael A; Hummel, Scott L; Hummel, Ellen K

    2017-01-01

    Evidence-based management has improved long-term survival in patients with heart failure (HF). However, an unintended consequence of increased longevity is that patients with HF are exposed to a greater symptom burden over time. In addition to classic symptoms such as dyspnea and edema, patients with HF frequently suffer additional symptoms such as pain, depression, gastrointestinal distress, and fatigue. In addition to obvious effects on quality of life, untreated symptoms increase clinical events including emergency department visits, hospitalizations, and long-term mortality in a dose-dependent fashion. Symptom management in patients with HF consists of two key components: comprehensive symptom assessment and sufficient knowledge of available approaches to alleviate the symptoms. Successful treatment addresses not just the physical but also the emotional, social, and spiritual aspects of suffering. Despite a lack of formal experience during cardiovascular training, symptom management in HF can be learned and implemented effectively by cardiology providers. Co-management with palliative medicine specialists can add significant value across the spectrum and throughout the course of HF.

  13. Assessment of respiratory flow cycle morphology in patients with chronic heart failure.

    PubMed

    Garde, Ainara; Sörnmo, Leif; Laguna, Pablo; Jané, Raimon; Benito, Salvador; Bayés-Genís, Antoni; Giraldo, Beatriz F

    2017-02-01

    Breathing pattern as periodic breathing (PB) in chronic heart failure (CHF) is associated with poor prognosis and high mortality risk. This work investigates the significance of a number of time domain parameters for characterizing respiratory flow cycle morphology in patients with CHF. Thus, our primary goal is to detect PB pattern and identify patients at higher risk. In addition, differences in respiratory flow cycle morphology between CHF patients (with and without PB) and healthy subjects are studied. Differences between these parameters are assessed by investigating the following three classification issues: CHF patients with PB versus with non-periodic breathing (nPB), CHF patients (both PB and nPB) versus healthy subjects, and nPB patients versus healthy subjects. Twenty-six CHF patients (8/18 with PB/nPB) and 35 healthy subjects are studied. The results show that the maximal expiratory flow interval is shorter and with lower dispersion in CHF patients than in healthy subjects. The flow slopes are much steeper in CHF patients, especially for PB. Both inspiration and expiration durations are reduced in CHF patients, mostly for PB. Using the classification and regression tree technique, the most discriminant parameters are selected. For signals shorter than 1 min, the time domain parameters produce better results than the spectral parameters, with accuracies for each classification of 82/78, 89/85, and 91/89 %, respectively. It is concluded that morphologic analysis in the time domain is useful, especially when short signals are analyzed.

  14. Optimal Allocation of Gold Standard Testing under Constrained Availability: Application to Assessment of HIV Treatment Failure

    PubMed Central

    Liu, Tao; Hogan, Joseph W.; Wang, Lisa; Zhang, Shangxuan; Kantor, Rami

    2013-01-01

    The World Health Organization (WHO) guidelines for monitoring the effectiveness of HIV treatment in resource-limited settings (RLS) are mostly based on clinical and immunological markers (e.g., CD4 cell counts). Recent research indicates that the guidelines are inadequate and can result in high error rates. Viral load (VL) is considered the “gold standard”, yet its widespread use is limited by cost and infrastructure. In this paper, we propose a diagnostic algorithm that uses information from routinely-collected clinical and immunological markers to guide a selective use of VL testing for diagnosing HIV treatment failure, under the assumption that VL testing is available only at a certain portion of patient visits. Our algorithm identifies the patient sub-population, such that the use of limited VL testing on them minimizes a pre-defined risk (e.g., misdiagnosis error rate). Diagnostic properties of our proposal algorithm are assessed by simulations. For illustration, data from the Miriam Hospital Immunology Clinic (RI, USA) are analyzed. PMID:24672142

  15. Application of a modified sequential organ failure assessment score to critically ill patients.

    PubMed

    Namendys-Silva, S A; Silva-Medina, M A; Vásquez-Barahona, G M; Baltazar-Torres, J A; Rivero-Sigarroa, E; Fonseca-Lazcano, J A; Domínguez-Cherit, G

    2013-02-01

    The purpose of the present study was to explore the usefulness of the Mexican sequential organ failure assessment (MEXSOFA) score for assessing the risk of mortality for critically ill patients in the ICU. A total of 232 consecutive patients admitted to an ICU were included in the study. The MEXSOFA was calculated using the original SOFA scoring system with two modifications: the PaO2/FiO2 ratio was replaced with the SpO2/FiO2 ratio, and the evaluation of neurologic dysfunction was excluded. The ICU mortality rate was 20.2%. Patients with an initial MEXSOFA score of 9 points or less calculated during the first 24 h after admission to the ICU had a mortality rate of 14.8%, while those with an initial MEXSOFA score of 10 points or more had a mortality rate of 40%. The MEXSOFA score at 48 h was also associated with mortality: patients with a score of 9 points or less had a mortality rate of 14.1%, while those with a score of 10 points or more had a mortality rate of 50%. In a multivariate analysis, only the MEXSOFA score at 48 h was an independent predictor for in-ICU death with an OR = 1.35 (95%CI = 1.14-1.59, P < 0.001). The SOFA and MEXSOFA scores calculated 24 h after admission to the ICU demonstrated a good level of discrimination for predicting the in-ICU mortality risk in critically ill patients. The MEXSOFA score at 48 h was an independent predictor of death; with each 1-point increase, the odds of death increased by 35%.

  16. TEP process flow diagram

    SciTech Connect

    Wilms, R Scott; Carlson, Bryan; Coons, James; Kubic, William

    2008-01-01

    This presentation describes the development of the proposed Process Flow Diagram (PFD) for the Tokamak Exhaust Processing System (TEP) of ITER. A brief review of design efforts leading up to the PFD is followed by a description of the hydrogen-like, air-like, and waterlike processes. Two new design values are described; the mostcommon and most-demanding design values. The proposed PFD is shown to meet specifications under the most-common and mostdemanding design values.

  17. Assessing Strategies for Heart Failure with Preserved Ejection Fraction at the Outpatient Clinic

    PubMed Central

    Jorge, Antonio José Lagoeiro; Rosa, Maria Luiza Garcia; Ribeiro, Mario Luiz; Fernandes, Luiz Claudio Maluhy; Freire, Monica Di Calafiori; Correia, Dayse Silva; Teixeira, Patrick Duarte; Mesquita, Evandro Tinoco

    2014-01-01

    Background: Heart failure with preserved ejection fraction (HFPEF) is the most common form of heart failure (HF), its diagnosis being a challenge to the outpatient clinic practice. Objective: To describe and compare two strategies derived from algorithms of the European Society of Cardiology Diastology Guidelines for the diagnosis of HFPEF. Methods: Cross-sectional study with 166 consecutive ambulatory patients (67.9±11.7 years; 72% of women). The strategies to confirm HFPEF were established according to the European Society of Cardiology Diastology Guidelines criteria. In strategy 1 (S1), tissue Doppler echocardiography (TDE) and electrocardiography (ECG) were used; in strategy 2 (S2), B-type natriuretic peptide (BNP) measurement was included. Results: In S1, patients were divided into groups based on the E/E'ratio as follows: GI, E/E'> 15 (n = 16; 9%); GII, E/E'8 to 15 (n = 79; 48%); and GIII, E/E'< 8 (n = 71; 43%). HFPEF was confirmed in GI and excluded in GIII. In GII, TDE [left atrial volume index (LAVI) ≥ 40 mL/m2; left ventricular mass index LVMI) > 122 for women and > 149 g/m2 for men] and ECG (atrial fibrillation) parameters were assessed, confirming HFPEF in 33 more patients, adding up to 49 (29%). In S2, patients were divided into three groups based on BNP levels. GI (BNP > 200 pg/mL) consisted of 12 patients, HFPEF being confirmed in all of them. GII (BNP ranging from 100 to 200 pg/mL) consisted of 20 patients with LAVI > 29 mL/m2, or LVMI ≥ 96 g/m2 for women or ≥ 116 g/m2 for men, or E/E'≥ 8 or atrial fibrillation on ECG, and the diagnosis of HFPEF was confirmed in 15. GIII (BNP < 100 pg/mL) consisted of 134 patients, 26 of whom had the diagnosis of HFPEF confirmed when GII parameters were used. Measuring BNP levels in S2 identified 4 more patients (8%) with HFPEF as compared with those identified in S1. Conclusion: The association of BNP measurement and TDE data is better than the isolated use of those parameters. BNP can be useful in

  18. An improved approach for flight readiness certification: Methodology for failure risk assessment and application examples. Volume 3: Structure and listing of programs

    NASA Technical Reports Server (NTRS)

    Moore, N. R.; Ebbeler, D. H.; Newlin, L. E.; Sutharshana, S.; Creager, M.

    1992-01-01

    An improved methodology for quantitatively evaluating failure risk of spaceflight systems to assess flight readiness and identify risk control measures is presented. This methodology, called Probabilistic Failure Assessment (PFA), combines operating experience from tests and flights with engineering analysis to estimate failure risk. The PFA methodology is of particular value when information on which to base an assessment of failure risk, including test experience and knowledge of parameters used in engineering analyses of failure phenomena, is expensive or difficult to acquire. The PFA methodology is a prescribed statistical structure in which engineering analysis models that characterize failure phenomena are used conjointly with uncertainties about analysis parameters and/or modeling accuracy to estimate failure probability distributions for specific failure modes. These distributions can then be modified, by means of statistical procedures of the PFA methodology, to reflect any test or flight experience. Conventional engineering analysis models currently employed for design of failure prediction are used in this methodology. The PFA methodology is described and examples of its application are presented. Conventional approaches to failure risk evaluation for spaceflight systems are discussed, and the rationale for the approach taken in the PFA methodology is presented. The statistical methods, engineering models, and computer software used in fatigue failure mode applications are thoroughly documented.

  19. Echocardiographic Assessment of Pulmonary Artery Systolic Pressure and Outcomes in Ambulatory Heart Failure Patients

    PubMed Central

    Kalogeropoulos, Andreas P.; Siwamogsatham, Sarawut; Hayek, Salim; Li, Song; Deka, Anjan; Marti, Catherine N.; Georgiopoulou, Vasiliki V.; Butler, Javed

    2014-01-01

    Background Pulmonary hypertension (PH) in patients with heart failure (HF) is associated with worse outcomes and is rapidly being recognized as a therapeutic target. To facilitate pragmatic research efforts, data regarding the prognostic importance of noninvasively assessed pulmonary artery systolic pressure (PASP) in stable ambulatory patients with HF are needed. Methods and Results We examined the association between echocardiographic PASP and outcomes in 417 outpatients with HF (age, 54±13 years; 60.7% men; 50.4% whites; 24.9% with preserved ejection fraction). Median PASP was 36 mm Hg (interquartile range [IQR]: 29, 46). After a median follow‐up of 2.6 years (IQR: 1.7, 3.9) there were 72 major events (57 deaths; 9 urgent heart transplants; and 6 ventricular assist device implantations) and 431 hospitalizations for HF. In models adjusting for clinical risk factors and therapy, a 10‐mm Hg higher PASP was associated with 37% higher risk (95% CI: 18, 59; P<0.001) for major events, and 11% higher risk (95% CI: 1, 23; P=0.039) for major events or HF hospitalization. The threshold that maximized the likelihood ratio for both endpoints was 48 mm Hg; those with PASP ≥48 mm Hg (N=84; 20.1%) had an adjusted hazard ratio of 3.33 (95% CI: 1.96, 5.65; P<0.001) for major events and 1.47 (95% CI: 1.02, 2.11; P=0.037) for major events or HF hospitalization. Reduced right ventricular systolic function had independent prognostic utility over PASP for adverse outcomes. Right atrial pressure and transtricuspid gradient both contributed to risk. Conclusions Elevated PASP, determined by echocardiography, identifies ambulatory patients with HF at increased risk for adverse events. PMID:24492947

  20. Evaluation of two methods for continuous cardiac output assessment during exercise in chronic heart failure patients.

    PubMed

    Kemps, Hareld M C; Thijssen, Eric J M; Schep, Goof; Sleutjes, Boudewijn T H M; De Vries, Wouter R; Hoogeveen, Adwin R; Wijn, Pieter F F; Doevendans, Pieter A F M

    2008-12-01

    The purpose of this study was to evaluate the accuracy of two techniques for the continuous assessment of cardiac output in patients with chronic heart failure (CHF): a radial artery pulse contour analysis method that uses an indicator dilution method for calibration (LiDCO) and an impedance cardiography technique (Physioflow), using the Fick method as a reference. Ten male CHF patients (New York Heart Association class II-III) were included. At rest, cardiac output values obtained by LiDCO and Physioflow were compared with those of the direct Fick method. During exercise, the continuous Fick method was used as a reference. Exercise, performed on a cycle ergometer in upright position, consisted of two constant-load tests at 30% and 80% of the ventilatory threshold and a symptom-limited maximal test. Both at rest and during exercise LiDCO showed good agreement with reference values [bias +/- limits of agreement (LOA), -1% +/- 28% and 2% +/- 28%, respectively]. In contrast, Physioflow overestimated reference values both at rest and during exercise (bias +/- LOA, 48% +/- 60% and 48% +/- 52%, respectively). Exercise-related within-patient changes of cardiac output, expressed as a percent change, showed for both techniques clinically acceptable agreement with reference values (bias +/- LOA: 2% +/- 26% for LiDCO, and -2% +/- 36% for Physioflow, respectively). In conclusion, although the limits of agreement with the Fick method are pretty broad, LiDCO provides accurate measurements of cardiac output during rest and exercise in CHF patients. Although Physioflow overestimates cardiac output, this method may still be useful to estimate relative changes during exercise.

  1. RIFLE criteria and hepatic function in the assessment of acute renal failure in liver transplantation.

    PubMed

    Tinti, F; Umbro, I; Meçule, A; Rossi, M; Merli, M; Nofroni, I; Corradini, S Ginanni; Poli, L; Pugliese, F; Ruberto, F; Berloco, P B; Mitterhofer, A P

    2010-05-01

    Renal dysfunction in cirrhotic patients is primary related to disturbances of circulatory function, triggered by portal hypertension with chronic intrarenal vasoconstriction and hypoperfusion. Pretransplant renal function is an important factor implicated in the development of acute renal failure (ARF) after liver transplantation (OLT), but other factors mostly related to liver function seem to influence the development of ARF. The Acute Dialysis Quality Initiative workgroup developed the RIFLE classification to define ARF. We sought to evaluate the incidence of ARF among patients undergoing OLT, to evaluate the association of ARF with pre-OLT renal and hepatic functions, and to evaluate the influence of ARF on chronic kidney disease (CKD) at 1 month post-OLT. Clinical, renal, hepatic function, and donor risk index data of 24 patients who underwent deceased donor OLT were collected before transplantation, in the perioperative period and in the first month post-OLT. ARF occurred in 37.5% of patients with 56% developing the R grade and 44% the I grade; no patient showed the F grade. An association was observed between ARF and a higher Model for End-Stage Liver Disease (MELD) score and between ARF and a reduced pre-OLT serum albumin. No association was noted between ARF and other pre-OLT parameters. In cirrhotic patients serum creatinine is a bias for renal function assessment and the Modification of Diet in Renal Disease formula overestimates GFR. Post-OLT CKD was present in 6.7% of patients without ARF and in 44.4% of patients with ARF. The R grade developed more frequently among patients with viral cirrhosis. The association of ARF with MELD and hypoalbuminemia may be the result of a close relationship between renal and hepatic functions among cirrhotic patients. Post-OLT CKD may be the result of unrecognized, preexisting CKD and/or the effects of not fully resolved acute damage to an injured kidney.

  2. Radiographic and echocardiographic assessment of left atrial size in 100 cats with acute left-sided congestive heart failure.

    PubMed

    Schober, Karsten E; Wetli, Ellen; Drost, Wm Tod

    2014-01-01

    The aims of this study were to evaluate left atrial size in cats with acute left-sided congestive heart failure. We hypothesized that left atrial size as determined by thoracic radiography can be normal in cats with acute left-sided congestive heart failure. One hundred cats with acute left-sided congestive heart failure in which thoracic radiography and echocardiography were performed within 12 h were identified. Left atrial size was evaluated using right lateral and ventrodorsal radiographs. Measurements were compared to two-dimensional echocardiographic variables of left atrial size and left ventricular size. On echocardiography, left atrial enlargement was observed in 96% cats (subjective assessment) whereas maximum left atrial dimension was increased (>15.7 mm) in 93% cats. On radiographs left atrial enlargement (subjective assessment) was found in 48% (lateral view), 53% (ventrodorsal view), and 64% (any view) of cats whereas left atrial enlargement was absent in 36% of cats in both views. Agreement between both methods of left atrial size estimation was poor (Cohen's kappa 0.17). Receiver operating characteristic curve analysis identified a maximum echocardiographic left atrial dimension of approximately 20 mm as the best compromise (Youden index) between sensitivity and specificity in the prediction of radiographic left atrial enlargement. Left atrial enlargement as assessed by thoracic radiography may be absent in a clinically relevant number of cats with congestive heart failure. Therefore, normal left atrial size on thoracic radiographs does not rule out presence of left-sided congestive heart failure in cats with clinical signs of respiratory distress.

  3. Wilson Loop Diagrams and Positroids

    NASA Astrophysics Data System (ADS)

    Agarwala, Susama; Marin-Amat, Eloi

    2017-03-01

    In this paper, we study a new application of the positive Grassmannian to Wilson loop diagrams (or MHV diagrams) for scattering amplitudes in N= 4 Super Yang-Mill theory ( N = 4 SYM). There has been much interest in studying this theory via the positive Grassmannians using BCFW recursion. This is the first attempt to study MHV diagrams for planar Wilson loop calculations (or planar amplitudes) in terms of positive Grassmannians. We codify Wilson loop diagrams completely in terms of matroids. This allows us to apply the combinatorial tools in matroid theory used to identify positroids (non-negative Grassmannians) to Wilson loop diagrams. In doing so, we find that certain non-planar Wilson loop diagrams define positive Grassmannians. While non-planar diagrams do not have physical meaning, this finding suggests that they may have value as an algebraic tool, and deserve further investigation.

  4. What can we learn by comparing students' diagram-construction processes with the mathematical conceptions inferred from their explanations with completed diagrams?

    NASA Astrophysics Data System (ADS)

    Lobato, Joanne; Hohensee, Charles; Diamond, Jaime Marie

    2014-09-01

    Despite recent research interest in student-created diagrams, little research has systematically investigated students' diagram- construction processes, meaning the order and manner in which students create markings as they physically generate diagrams. In this study, we characterize the various processes students use to create diagrams that represent a quadratic motion situation involving increasing speed, and we explore how these diagram-construction processes are related to students' conceptions of speed as inferred from their explanations with their completed diagrams. Previous literature suggests contrasting predictions regarding whether or not students' diagram-construction processes are closely related (from our perspective as researchers) to students' inferred conceptions. We see the study as having value for research and practice by raising new questions related to diagram-construction processes, pointing to the potential formative assessment value of attending to diagram-construction processes, and demonstrating the need for the development of theory to explain the relationships identified by this study.

  5. Porcine model characterizing various parameters assessing the outcome after acetaminophen intoxication induced acute liver failure

    PubMed Central

    Thiel, Karolin; Klingert, Wilfried; Klingert, Kathrin; Morgalla, Matthias H; Schuhmann, Martin U; Leckie, Pamela; Sharifi, Yalda; Davies, Nathan A; Jalan, Rajiv; Peter, Andreas; Grasshoff, Christian; Königsrainer, Alfred; Schenk, Martin; Thiel, Christian

    2017-01-01

    AIM To investigate the changes of hemodynamic and laboratory parameters during the course of acute liver failure following acetaminophen overdose. METHODS Eight pigs underwent a midline laparotomy following jejunal catheter placement for further acetaminophen intoxication and positioning of a portal vein Doppler flow-probe. Acute liver failure was realized by intrajejunal acetaminophen administration in six animals, two animals were sham operated. All animals were invasively monitored and received standardized intensive care support throughout the study. Portal blood flow, hemodynamic and ventilation parameters were continuously recorded. Laboratory parameters were analysed every eight hours. Liver biopsies were sampled every 24 h following intoxication and upon autopsy. RESULTS Acute liver failure (ALF) occurred after 28 ± 5 h resulted in multiple organ failure and death despite maximal support after further 21 ± 1 h (study end). Portal blood flow (baseline 1100 ± 156 mL/min) increased to a maximum flow of 1873 ± 175 mL/min at manifestation of ALF, which was significantly elevated (P < 0.01). Immediately after peaking, portal flow declined rapidly to 283 ± 135 mL/min at study end. Thrombocyte values (baseline 307 × 103/µL ± 34 × 103/µL) of intoxicated animals declined slowly to values of 145 × 103/µL ± 46 × 103/µL when liver failure occurred. Subsequent appearance of severe thrombocytopenia in liver failure resulted in values of 11 × 103/µL ± 3 × 103/µL preceding fatality within few hours which was significant (P > 0.01). CONCLUSION Declining portal blood flow and subsequent severe thrombocytopenia after acetaminophen intoxication precede fatality in a porcine acute liver failure model. PMID:28321158

  6. Warped penguin diagrams

    SciTech Connect

    Csaki, Csaba; Grossman, Yuval; Tanedo, Philip; Tsai, Yuhsin

    2011-04-01

    We present an analysis of the loop-induced magnetic dipole operator in the Randall-Sundrum model of a warped extra dimension with anarchic bulk fermions and an IR brane-localized Higgs. These operators are finite at one-loop order and we explicitly calculate the branching ratio for {mu}{yields}e{gamma} using the mixed position/momentum space formalism. The particular bound on the anarchic Yukawa and Kaluza-Klein (KK) scales can depend on the flavor structure of the anarchic matrices. It is possible for a generic model to either be ruled out or unaffected by these bounds without any fine-tuning. We quantify how these models realize this surprising behavior. We also review tree-level lepton flavor bounds in these models and show that these are on the verge of tension with the {mu}{yields}e{gamma} bounds from typical models with a 3 TeV Kaluza-Klein scale. Further, we illuminate the nature of the one-loop finiteness of these diagrams and show how to accurately determine the degree of divergence of a five-dimensional loop diagram using both the five-dimensional and KK formalism. This power counting can be obfuscated in the four-dimensional Kaluza-Klein formalism and we explicitly point out subtleties that ensure that the two formalisms agree. Finally, we remark on the existence of a perturbative regime in which these one-loop results give the dominant contribution.

  7. Proactive Risk Assessment of Blood Transfusion Process, in Pediatric Emergency, Using the Health Care Failure Mode and Effects Analysis (HFMEA)

    PubMed Central

    Dehnavieh, Reza; Ebrahimipour, Hossein; Molavi-Taleghani, Yasamin; Vafaee-Najar, Ali; Hekmat, Somayeh Noori; Esmailzdeh, Hamid

    2015-01-01

    Introduction: Pediatric emergency has been considered as a high risk area, and blood transfusion is known as a unique clinical measure, therefore this study was conducted with the purpose of assessing the proactive risk assessment of blood transfusion process in Pediatric Emergency of Qaem education- treatment center in Mashhad, by the Healthcare Failure Mode and Effects Analysis (HFMEA) methodology. Methodology: This cross-sectional study analyzed the failure mode and effects of blood transfusion process by a mixture of quantitative-qualitative method. The proactive HFMEA was used to identify and analyze the potential failures of the process. The information of the items in HFMEA forms was collected after obtaining a consensus of experts’ panel views via the interview and focus group discussion sessions. Results: The Number of 77 failure modes were identified for 24 sub-processes enlisted in 8 processes of blood transfusion. Totally 13 failure modes were identified as non-acceptable risk (a hazard score above 8) in the blood transfusion process and were transferred to the decision tree. Root causes of high risk modes were discussed in cause-effect meetings and were classified based on the UK national health system (NHS) approved classifications model. Action types were classified in the form of acceptance (11.6%), control (74.2%) and elimination (14.2%). Recommendations were placed in 7 categories using TRIZ (“Theory of Inventive Problem Solving.”) Conclusion: The re-engineering process for the required changes, standardizing and updating the blood transfusion procedure, root cause analysis of blood transfusion catastrophic events, patient identification bracelet, training classes and educational pamphlets for raising awareness of personnel, and monthly gathering of transfusion medicine committee have all been considered as executive strategies in work agenda in pediatric emergency. PMID:25560332

  8. Using Eye Tracking to Investigate Semantic and Spatial Representations of Scientific Diagrams during Text-Diagram Integration

    ERIC Educational Resources Information Center

    Jian, Yu-Cin; Wu, Chao-Jung

    2015-01-01

    We investigated strategies used by readers when reading a science article with a diagram and assessed whether semantic and spatial representations were constructed while reading the diagram. Seventy-one undergraduate participants read a scientific article while tracking their eye movements and then completed a reading comprehension test. Our…

  9. Pregnancy in women with heart disease: risk assessment and management of heart failure.

    PubMed

    Grewal, Jasmine; Silversides, Candice K; Colman, Jack M

    2014-01-01

    Heart disease, present in 0.5% to 3% of pregnant women, is an important cause of morbidity and the leading cause of death among pregnant women in the developed world. Certain heart conditions are associated with an increased risk of heart failure during pregnancy or the postpartum period; for these conditions, management during pregnancy benefits from multidisciplinary care at a center with expertise in pregnancy and heart disease. This article focuses on cardiac risks and management strategies for women with acquired and congenital heart disease who are at increased risk of heart failure during pregnancy.

  10. Program Synthesizes UML Sequence Diagrams

    NASA Technical Reports Server (NTRS)

    Barry, Matthew R.; Osborne, Richard N.

    2006-01-01

    A computer program called "Rational Sequence" generates Universal Modeling Language (UML) sequence diagrams of a target Java program running on a Java virtual machine (JVM). Rational Sequence thereby performs a reverse engineering function that aids in the design documentation of the target Java program. Whereas previously, the construction of sequence diagrams was a tedious manual process, Rational Sequence generates UML sequence diagrams automatically from the running Java code.

  11. Risk assessment of the emergency processes: Healthcare failure mode and effect analysis

    PubMed Central

    Taleghani, Yasamin Molavi; Rezaei, Fatemeh; Sheikhbardsiri, Hojat

    2016-01-01

    BACKGROUND: Ensuring about the patient’s safety is the first vital step in improving the quality of care and the emergency ward is known as a high-risk area in treatment health care. The present study was conducted to evaluate the selected risk processes of emergency surgery department of a treatment-educational Qaem center in Mashhad by using analysis method of the conditions and failure effects in health care. METHODS: In this study, in combination (qualitative action research and quantitative cross-sectional), failure modes and effects of 5 high-risk procedures of the emergency surgery department were identified and analyzed according to Healthcare Failure Mode and Effects Analysis (HFMEA). To classify the failure modes from the “nursing errors in clinical management model (NECM)”, the classification of the effective causes of error from “Eindhoven model” and determination of the strategies to improve from the “theory of solving problem by an inventive method” were used. To analyze the quantitative data of descriptive statistics (total points) and to analyze the qualitative data, content analysis and agreement of comments of the members were used. RESULTS: In 5 selected processes by “voting method using rating”, 23 steps, 61 sub-processes and 217 potential failure modes were identified by HFMEA. 25 (11.5%) failure modes as the high risk errors were detected and transferred to the decision tree. The most and the least failure modes were placed in the categories of care errors (54.7%) and knowledge and skill (9.5%), respectively. Also, 29.4% of preventive measures were in the category of human resource management strategy. CONCLUSION: “Revision and re-engineering of processes”, “continuous monitoring of the works”, “preparation and revision of operating procedures and policies”, “developing the criteria for evaluating the performance of the personnel”, “designing a suitable educational content for needs of employee”,

  12. Heart Failure

    MedlinePlus

    ... version of this page please turn Javascript on. Heart Failure What is Heart Failure? In heart failure, the heart cannot pump enough ... failure often experience tiredness and shortness of breath. Heart Failure is Serious Heart failure is a serious and ...

  13. Diagonal Slices of 3D Young Diagrams in the Approach of Maya Diagrams

    NASA Astrophysics Data System (ADS)

    Cai, Li-Qiang; Wang, Li-Fang; Wu, Ke; Yang, Jie

    2014-09-01

    According to the correspondence between 2D Young diagrams and Maya diagrams and the relation between 2D and 3D Young diagrams, we construct 3D Young diagrams in the approach of Maya diagrams. Moreover, we formulate the generating function of 3D Young diagrams, which is the MacMahon function in terms of Maya diagrams.

  14. Using Workflow Diagrams to Address Hand Hygiene in Pediatric Long-Term Care Facilities.

    PubMed

    Carter, Eileen J; Cohen, Bevin; Murray, Meghan T; Saiman, Lisa; Larson, Elaine L

    2015-01-01

    Hand hygiene (HH) in pediatric long-term care settings has been found to be sub-optimal. Multidisciplinary teams at three pediatric long-term care facilities developed step-by-step workflow diagrams of commonly performed tasks highlighting HH opportunities. Diagrams were validated through observation of tasks and concurrent diagram assessment. Facility teams developed six workflow diagrams that underwent 22 validation observations. Four main themes emerged: 1) diagram specificity, 2) wording and layout, 3) timing of HH indications, and 4) environmental hygiene. The development of workflow diagrams is an opportunity to identify and address the complexity of HH in pediatric long-term care facilities.

  15. Potential-pH Diagrams.

    ERIC Educational Resources Information Center

    Barnum, Dennis W.

    1982-01-01

    Potential-pH diagrams show the domains of redoxpotential and pH in which major species are most stable. Constructing such diagrams provides students with opportunities to decide what species must be considered, search literature for equilibrium constants and free energies of formation, and practice in using the Nernst equation. (Author/JN)

  16. Micro-compression: a novel technique for the nondestructive assessment of local bone failure.

    PubMed

    Müller, R; Gerber, S C; Hayes, W C

    1998-12-01

    Many bones within the axial and appendicular skeleton are subjected to repetitive, cyclic loading during the course of ordinary daily activities. If this repetitive loading is of sufficient magnitude or duration, fatigue failure of the bone tissue may result. In clinical orthopedics, trabecular fatigue fractures are observed as compressive stress fractures in the proximal femur, vertebrae, calcaneus and tibia, and are often preceded by buckling and bending of microstructural elements. However, the relative importance of bone density and architecture in the etiology of these fractures is poorly understood. The aim of the study was to investigate failure mechanisms of 3D trabecular bone using micro-computed tomography (microCT). Because of its nondestructive nature, microCT represents an ideal approach for performing not only static measurements of bone architecture but also dynamic measurements of failure initiation and propagation as well as damage accumulation. For the purpose of the study, a novel micro-compression device was devised to measure loaded trabecular bone specimens directly in a micro-tomographic system. The measurement window in the device was made of a radiolucent, highly stiff plastic to enable X-rays to penetrate the material. The micro-compressor has an outer diameter of 19 mm and a total length of 65 mm. The internal load chamber fits wet or dry bone specimens with maximal diameters of 9 mm and maximal lengths of 22 mm. For the actual measurement, first, the unloaded bone is measured in the microCT. Second, a load-displacement curve is recorded where the load is measured with an integrated mini-button load cell and the displacement is computed directly from the microCT scout-view. For each load case, a 3D snap-shot of the structure under load is taken providing 34 microm nominal resolution. Initial measurements included specimens from bovine tibiae and whale spine to investigate the influence of the structure type on the failure mechanism. In a

  17. Risk Assessment of Using Entonox for the Relief of Labor Pain: A Healthcare Failure Modes and Effects Analysis Approach

    PubMed Central

    Najafi, Tahereh Fathi; Bahri, Narjes; Ebrahimipour, Hosein; Najar, Ali Vafaee; Taleghani, Yasamin Molavi

    2016-01-01

    Introduction In order to prevent medical errors, it is important to know why they occur and to identify their causes. Healthcare failure modes and effects analysis (HFMEA) is a type of qualitative descriptive that is used to evaluate the risk. The aim of this study was to assess the risks of using Entonox for labor pain by HFMEA. Methods A mixed-methods design (qualitative action research and quantitative cross-sectional research) was used. The modes and effects of failures in the process of using Entonox were detected and analyzed during 2013–2014 at Hefdahe Shahrivar Hospital, Mashhad, Iran. Overall, 52 failure modes were identified, with 25 being recognized as high-risk modes. Results The results revealed that 48.5% of these errors fall into the care process type, 22.05% belong to the communicative type, 19.1% fall into the administrative type, and 10.2% are of the knowledge and skills type. Strategies were presented in the forms of acceptance (3.2%), control (90.3%), and elimination (6.4%). Conclusion The following actions are suggested for improving the process of using Entonox: Close supervision by the midwife, precise recording of all the stages of the process in the woman’s medical record, the necessity of the presence of the anesthesiologist at the woman’s bedside during labor, confirming the indications for use of Entonox, and close monitoring to ensure the safety of the gas cylinder guards. PMID:27123224

  18. Development of Methodology to Assess the Failure Behaviour of Bamboo Single Fibre by Acoustic Emission Technique

    NASA Astrophysics Data System (ADS)

    Alam, Md. Saiful; Gulshan, Fahmida; Ahsan, Qumrul; Wevers, Martine; Pfeiffer, Helge; van Vuure, Aart-Willem; Osorio, Lina; Verpoest, Ignaas

    2017-04-01

    Acoustic emission (AE) was used as a tool for detecting, evaluating and for better understanding of the damage mechanism and failure behavior in composites during mechanical loading. Methodology was developed for tensile test of natural fibres (bamboo single fibre). A series of experiments were performed and load drops (one or two) were observed in the load versus time graphs. From the observed AE parameters such as amplitude, energy, duration etc. significant information corresponding to the load drops were found. These AE signals from the load drop occurred from such failure as debonding between two elementary fibre or from join of elementary fibre at edge. The various sources of load at first load drop was not consistent for the different samples (for a particular sample the value is 8 N, stress: 517.51 MPa). Final breaking of fibre corresponded to saturated level AE amplitude of preamplifier (99.9 dB) for all samples. Therefore, it was not possible to determine the exact AE energy value for final breaking. Same methodology was used for tensile test of three single fibres, which gave clear indication of load drop before the final breaking of first and second fibre.

  19. Failure assessment of aluminum liner based filament-wound hybrid riser subjected to internal hydrostatic pressure

    NASA Astrophysics Data System (ADS)

    Dikshit, Vishwesh; Seng, Ong Lin; Maheshwari, Muneesh; Asundi, A.

    2015-03-01

    The present study describes the burst behavior of aluminum liner based prototype filament-wound hybrid riser under internal hydrostatic pressure. The main objective of present study is to developed an internal pressure test rig set-up for filament-wound hybrid riser and investigate the failure modes of filament-wound hybrid riser under internal hydrostatic burst pressure loading. The prototype filament-wound hybrid riser used for burst test consists of an internal aluminum liner and outer composite layer. The carbon-epoxy composites as part of the filament-wound hybrid risers were manufactured with [±55o] lay-up pattern with total composite layer thickness of 1.6 mm using a CNC filament-winding machine. The burst test was monitored by video camera which helps to analyze the failure mechanism of the fractured filament-wound hybrid riser. The Fiber Bragg Grating (FBG) sensor was used to monitor and record the strain changes during burst test of prototype filament-wound hybrid riser. This study shows good improvements in burst strength of filament-wound hybrid riser compared to the monolithic metallic riser. Since, strain measurement using FBG sensors has been testified as a reliable method, we aim to further understand in detail using this technique.

  20. Development of Methodology to Assess the Failure Behaviour of Bamboo Single Fibre by Acoustic Emission Technique

    NASA Astrophysics Data System (ADS)

    Alam, Md. Saiful; Gulshan, Fahmida; Ahsan, Qumrul; Wevers, Martine; Pfeiffer, Helge; van Vuure, Aart-Willem; Osorio, Lina; Verpoest, Ignaas

    2016-06-01

    Acoustic emission (AE) was used as a tool for detecting, evaluating and for better understanding of the damage mechanism and failure behavior in composites during mechanical loading. Methodology was developed for tensile test of natural fibres (bamboo single fibre). A series of experiments were performed and load drops (one or two) were observed in the load versus time graphs. From the observed AE parameters such as amplitude, energy, duration etc. significant information corresponding to the load drops were found. These AE signals from the load drop occurred from such failure as debonding between two elementary fibre or from join of elementary fibre at edge. The various sources of load at first load drop was not consistent for the different samples (for a particular sample the value is 8 N, stress: 517.51 MPa). Final breaking of fibre corresponded to saturated level AE amplitude of preamplifier (99.9 dB) for all samples. Therefore, it was not possible to determine the exact AE energy value for final breaking. Same methodology was used for tensile test of three single fibres, which gave clear indication of load drop before the final breaking of first and second fibre.

  1. Students' different understandings of class diagrams

    NASA Astrophysics Data System (ADS)

    Boustedt, Jonas

    2012-03-01

    The software industry needs well-trained software designers and one important aspect of software design is the ability to model software designs visually and understand what visual models represent. However, previous research indicates that software design is a difficult task to many students. This article reports empirical findings from a phenomenographic investigation on how students understand class diagrams, Unified Modeling Language (UML) symbols, and relations to object-oriented (OO) concepts. The informants were 20 Computer Science students from four different universities in Sweden. The results show qualitatively different ways to understand and describe UML class diagrams and the "diamond symbols" representing aggregation and composition. The purpose of class diagrams was understood in a varied way, from describing it as a documentation to a more advanced view related to communication. The descriptions of class diagrams varied from seeing them as a specification of classes to a more advanced view, where they were described to show hierarchic structures of classes and relations. The diamond symbols were seen as "relations" and a more advanced way was seeing the white and the black diamonds as different symbols for aggregation and composition. As a consequence of the results, it is recommended that UML should be adopted in courses. It is briefly indicated how the phenomenographic results in combination with variation theory can be used by teachers to enhance students' possibilities to reach advanced understanding of phenomena related to UML class diagrams. Moreover, it is recommended that teachers should put more effort in assessing skills in proper usage of the basic symbols and models and students should be provided with opportunities to practise collaborative design, e.g. using whiteboards.

  2. Doppler assessment of brachial artery flow as a measure of endothelial dysfunction in pediatric chronic renal failure.

    PubMed

    Hussein, Gehan; Bughdady, Yasser; Kandil, Manal E; Bazaraa, Hafez M; Taher, Heba

    2008-11-01

    Cardiovascular morbidity and mortality are highly prevalent among patients with chronic renal failure (CRF). Endothelial dysfunction is regarded as the initial reversible step in the development of atherosclerosis and has been demonstrated in all stages of renal failure. Non-invasive techniques to assess endothelial function have been recently developed and have been proven to predict future mortality in adults. We aimed to assess endothelial function in children with stage 4 chronic kidney disease (CKD 4) on conservative treatment, using a-non invasive, high-resolution, ultrasound Doppler study of the brachial artery flow, correlating it with other clinical and laboratory parameters. This study included 34 children with CKD 4 on conservative treatment who were compared with 30 healthy controls. Flow-mediated dilatation (FMD), nitroglycerin-mediated dilatation (NTG-MD) and FMD/NTG-MD ratio were estimated. FMD was abnormal (< 5%) in 24 patients (71%). FMD and FMD/NTG-MD ratio were significantly lower in patients than in controls (P = 0.001 and P = 0.01, respectively). FMD correlated positively with serum calcium and negatively with alkaline phosphatase. We concluded that endothelial dysfunction is present in children with CKD 4 on conservative treatment and may reflect increased atherogenic and thrombogenic properties of the endothelium, contributing to subsequent adverse cardiovascular outcome.

  3. Assessing validity by comparing transition and static measures of dyspnea in patients with acute decompensated heart failure.

    PubMed

    Smithline, Howard A; Caglar, Selin; Blank, Fidela S J

    2010-01-01

    This study assessed the convergent validity of 2 dyspnea measures, the transition measure and the change measure, by comparing them with each other in patients admitted to the hospital with acute decompensated heart failure. Static measures of dyspnea were obtained at baseline (pre-static measure) and at time 1 hour and 4 hour (post-static measures). The change measure was calculated as the difference between the pre-static and post-static measures. Transition measures were obtained at time 1 hour and 4 hour. Visual analog scales and Likert scales were used. Both physicians and patients measured the dyspnea independently. A total of 112 patients had complete data sets at time 0 and 1 hour and 86 patients had complete data sets at all 3 time points. Correlations were calculated between the transition measures and static measures (pre-static, post-static, and change measure). Bland-Altman plots were generated and the mean difference and limits of agreement between the transition measures and the change measures were calculated. In general, short-term dyspnea assessment using transition measures and serial static measures can not be used to validate each other in this population of patients being admitted with acute decompensated heart failure.

  4. Risk assessment of Giardia from a full scale MBR sewage treatment plant caused by membrane integrity failure.

    PubMed

    Zhang, Yu; Chen, Zhimin; An, Wei; Xiao, Shumin; Yuan, Hongying; Zhang, Dongqing; Yang, Min

    2015-04-01

    Membrane bioreactors (MBR) are highly efficient at intercepting particles and microbes and have become an important technology for wastewater reclamation. However, many pathogens can accumulate in activated sludge due to the long residence time usually adopted in MBR, and thus may pose health risks when membrane integrity problems occur. This study presents data from a survey on the occurrence of water-borne Giardia pathogens in reclaimed water from a full-scale wastewater treatment plant with MBR experiencing membrane integrity failure, and assessed the associated risk for green space irrigation. Due to membrane integrity failure, the MBR effluent turbidity varied between 0.23 and 1.90 NTU over a period of eight months. Though this turbidity level still met reclaimed water quality standards (≤5 NTU), Giardia were detected at concentrations of 0.3 to 95 cysts/10 L, with a close correlation between effluent turbidity and Giardia concentration. All β-giardin gene sequences of Giardia in the WWTP influents were genotyped as Assemblages A and B, both of which are known to infect humans. An exponential dose-response model was applied to assess the risk of infection by Giardia. The risk in the MBR effluent with chlorination was 9.83×10(-3), higher than the acceptable annual risk of 1.0×10(-4). This study suggested that membrane integrity is very important for keeping a low pathogen level, and multiple barriers are needed to ensure the biological safety of MBR effluent.

  5. An assessment of BWR (boiling water reactor) Mark-II containment challenges, failure modes, and potential improvements in performance

    SciTech Connect

    Kelly, D.L.; Jones, K.R.; Dallman, R.J. ); Wagner, K.C. )

    1990-07-01

    This report assesses challenges to BWR Mark II containment integrity that could potentially arise from severe accidents. Also assessed are some potential improvements that could prevent core damage or containment failure, or could mitigate the consequences of such failure by reducing the release of fission products to the environment. These challenges and improvements are analyzed via a limited quantitative risk/benefit analysis of a generic BWR/4 reactor with Mark II containment. Point estimate frequencies of the dominant core damage sequences are obtained and simple containment event trees are constructed to evaluate the response of the containment to these severe accident sequences. The resulting containment release modes are then binned into source term release categories, which provide inputs to the consequence analysis. The output of the consequences analysis is used to construct an overall base case risk profile. Potential improvements and sensitivities are evaluated by modifying the event tree spilt fractions, thus generating a revised risk profile. Several important sensitivity cases are examined to evaluate the impact of phenomenological uncertainties on the final results. 75 refs., 25 figs., 65 tabs.

  6. Assessing Risk and Preventing 30-Day Readmissions in Decompensated Heart Failure: Opportunity to Intervene?

    PubMed

    Dunbar-Yaffe, Richard; Stitt, Audra; Lee, Joseph J; Mohamed, Shanas; Lee, Douglas S

    2015-10-01

    Heart failure (HF) patients are at high risk of hospital readmission, which contributes to substantial health care costs. There is great interest in strategies to reduce rehospitalization for HF. However, many readmissions occur within 30 days of initial hospital discharge, presenting a challenge for interventions to be instituted in a short time frame. Potential strategies to reduce readmissions for HF can be classified into three different forms. First, patients who are at high risk of readmission can be identified even before their initial index hospital discharge. Second, ambulatory remote monitoring strategies may be instituted to identify early warning signs before acute decompensation of HF occurs. Finally, strategies may be employed in the emergency department to identify low-risk patients who may not need hospital readmission. If symptoms improve with initial therapy, low-risk patients could be referred to specialized, rapid outpatient follow-up care where investigations and therapy can occur in an outpatient setting.

  7. [Assessment of natriuretic peptide indices and oxidative stress in patients with chronic heart failure].

    PubMed

    Abezov, D K; Kamilova, U K; Shukurdzhanova, S M; Rakhmonov, R R; Alieva, T A

    2010-01-01

    The authors have studied indices of natriuretic peptide and oxidative stress in patients with chronic heart failure (CHF). 52 male patients with postinfarction cardiosclerosis (PICS) who have developed CHF have been observed. The age of the patients varied from 38 till 60. It was established that CHF patients with progression of the disease had worsening of their clinical condition together with an increase of oxidative stress which was characterized through decrease of NO metabolites, NADPH--diaphorase (eNOS), increase of nitrite reductase (iNOS) and peroxinitrite (ONOO), correlative increase the level of brain natriuretic peptide in blood plazma. Reliable connection between considerable increase of oxidative stress and the level of NT-pro BNP was noted in CHF patients, which demands necessity of correction of observed disorders.

  8. Assessing cell fusion and cytokinesis failure as mechanisms of clone 9 hepatocyte multinucleation in vitro.

    PubMed

    Simic, Damir; Euler, Catherine; Thurby, Christina; Peden, Mike; Tannehill-Gregg, Sarah; Bunch, Todd; Sanderson, Thomas; Van Vleet, Terry

    2012-08-01

    In this in vitro model of hepatocyte multinucleation, separate cultures of rat Clone 9 cells are labeled with either red or green cell tracker dyes (Red Cell Tracker CMPTX or Vybrant CFDA SE Cell Tracer), plated together in mixed-color colonies, and treated with positive or negative control agents for 4 days. The fluorescent dyes become cell-impermeant after entering cells and are not transferred to adjacent cells in a population, but are inherited by daughter cells after fusion. The mixed-color cultures are then evaluated microscopically for multinucleation and analysis of the underlying mechanism (cell fusion/cytokinesis). Multinucleated cells containing only one dye have undergone cytokinesis failure, whereas dual-labeled multinucleated cells have resulted from fusion.

  9. Particles, Feynman Diagrams and All That

    ERIC Educational Resources Information Center

    Daniel, Michael

    2006-01-01

    Quantum fields are introduced in order to give students an accurate qualitative understanding of the origin of Feynman diagrams as representations of particle interactions. Elementary diagrams are combined to produce diagrams representing the main features of the Standard Model.

  10. Atemporal diagrams for quantum circuits

    SciTech Connect

    Griffiths, Robert B.; Wu Shengjun; Yu Li; Cohen, Scott M.

    2006-05-15

    A system of diagrams is introduced that allows the representation of various elements of a quantum circuit, including measurements, in a form which makes no reference to time (hence 'atemporal'). It can be used to relate quantum dynamical properties to those of entangled states (map-state duality), and suggests useful analogies, such as the inverse of an entangled ket. Diagrams clarify the role of channel kets, transition operators, dynamical operators (matrices), and Kraus rank for noisy quantum channels. Positive (semidefinite) operators are represented by diagrams with a symmetry that aids in understanding their connection with completely positive maps. The diagrams are used to analyze standard teleportation and dense coding, and for a careful study of unambiguous (conclusive) teleportation. A simple diagrammatic argument shows that a Kraus rank of 3 is impossible for a one-qubit channel modeled using a one-qubit environment in a mixed state.

  11. The Hertzsprung-Russell Diagram.

    ERIC Educational Resources Information Center

    Woodrow, Janice

    1991-01-01

    Describes a classroom use of the Hertzsprung-Russell diagram to infer not only the properties of a star but also the star's probable stage in evolution, life span, and age of the cluster in which it is located. (ZWH)

  12. Ion mixing and phase diagrams

    NASA Astrophysics Data System (ADS)

    Lau, S. S.; Liu, B. X.; Nicolet, M.-A.

    1983-05-01

    Interactions induced by ion irradiation are generally considered to be non-equilibrium processes, whereas phase diagrams are determined by phase equilibria. These two entities are seemingly unrelated. However, if one assumes that quasi-equilibrium conditions prevail after the prompt events, subsequent reactions are driven toward equilibrium by thermodynamical forces. Under this assumption, ion-induced reactions are related to equilibrium and therefore to phase diagrams. This relationship can be seen in the similarity that exists in thin films between reactions induced by ion irradiation and reactions induced by thermal annealing. In the latter case, phase diagrams have been used to predict the phase sequence of stable compound formation, notably so in cases of silicide formation. Ion-induced mixing not only can lead to stable compound formation, but also to metastable alloy formation. In some metal-metal systems, terminal solubilities can be greatly extended by ion mixing. In other cases, where the two constituents of the system have different crystal structures, extension of terminal solubility from both sides of the phase diagram eventually becomes structurally incompatible and a glassy (amorphous) mixture can form. The composition range where this bifurcation is likely to occur is in the two-phase regions of the phase diagram. These concepts are potentially useful guides in selecting metal pairs that from metallic glasses by ion mixing. In this report, phenomenological correlation between stable (and metastable) phase formation and phase diagram is discussed in terms of recent experimental data.

  13. Assessing the Effects of the "Rocket Math" Program with a Primary Elementary School Student at Risk for School Failure: A Case Study

    ERIC Educational Resources Information Center

    Smith, Christina R.; Marchand-Martella, Nancy E.; Martella, Ronald C.

    2011-01-01

    This study assessed the effects of the "Rocket Math" program on the math fluency skills of a first grade student at risk for school failure. The student received instruction in the "Rocket Math" program over 6 months. He was assessed using a pre- and posttest curriculum-based measurement (CBM) and individualized fluency checkouts within the…

  14. Failure Impact Analysis of Key Management in AMI Using Cybernomic Situational Assessment (CSA)

    SciTech Connect

    Abercrombie, Robert K; Sheldon, Frederick T; Hauser, Katie R; Lantz, Margaret W; Mili, Ali

    2013-01-01

    In earlier work, we presented a computational framework for quantifying the security of a system in terms of the average loss a stakeholder stands to sustain as a result of threats to the system. We named this system, the Cyberspace Security Econometrics System (CSES). In this paper, we refine the framework and apply it to cryptographic key management within the Advanced Metering Infrastructure (AMI) as an example. The stakeholders, requirements, components, and threats are determined. We then populate the matrices with justified values by addressing the AMI at a higher level, rather than trying to consider every piece of hardware and software involved. We accomplish this task by leveraging the recently established NISTR 7628 guideline for smart grid security. This allowed us to choose the stakeholders, requirements, components, and threats realistically. We reviewed the literature and selected an industry technical working group to select three representative threats from a collection of 29 threats. From this subset, we populate the stakes, dependency, and impact matrices, and the threat vector with realistic numbers. Each Stakeholder s Mean Failure Cost is then computed.

  15. Assessment of composite failure and ultimate strength without experiment on composite

    NASA Astrophysics Data System (ADS)

    Huang, Zheng-Ming; Liu, Ling

    2014-08-01

    This paper attempts to estimate the ultimate strength of a laminated composite only based on its constituent properties measured independently. Three important issues involved have been systematically addressed, i.e., stress calculation for the constituent fiber and matrix materials, failure detection for the lamina and laminate upon the internal stresses in their constituents, and input data determination of the constituents from monolithic measurements. There are three important factors to influence the accuracy of the strength prediction. One is the stress concentration factor (SCF) in the matrix. Another is matrix plasticity. The third is thermal residual stresses in the constituents. It is these three factors, however, that have not been sufficiently well realized in the composite community. One can easily find out the elastic and strength parameters of a great many laminae and laminates in the current literature. Unfortunately, necessary information to determine the SCF, the matrix plasticity, and the thermal residual stresses of the composites is rare or incomplete. A useful design methodology is demonstrated in the paper.

  16. Assessment of Cost and Health Resource Utilization for Elderly Patients With Heart Failure and Diabetes Mellitus

    PubMed Central

    BOGNER, HILLARY R.; MILLER, STEVEN D.; DE VRIES, HEATHER F.; CHHATRE, SUMEDHA; JAYADEVAPPA, RAVISHANKAR

    2010-01-01

    Background Our aim was to examine the health resource utilization and cost of care associated with heart failure (HF) and diabetes mellitus (DM) for elderly Medicare enrollees. Methods and Results A retrospective case-control design was used to identify 4 groups of elderly patients with HF and DM (n = 498), HF only (n = 1089), DM only (n = 971), and no-HF and no-DM (n = 5438) using an administrative database of a large urban academic health care system. Demographic, diagnostic, health resource utilization, and cost (reimbursement) data were obtained from the Medicare claims database for the years 2000 and 2001. Disease states were identified by ICD-9 codes. Costs and health resource utilization were compared across the groups. The mean total costs were highest for the group with HF and DM ($32,676), and second highest for the HF only group ($22,230). In multivariable models that adjusted for potentially influential covariates, the group with HF and DM had a 3-fold increase in total cost compared with the group without DM and HF (relative total cost = 4.51, 95% confidence interval 3.82–5.31). Conclusions The presence of DM has a substantial influence on the costs for managing older patients with HF. An integrated approach to management may be needed. PMID:20610226

  17. A harvest failure approach to assess the threat from an invasive species.

    PubMed

    Yemshanov, Denys; McKenney, Daniel W; de Groot, Peter; Haugen, Dennis; Pedlar, John; Sidders, Derek; Joss, Brent

    2011-01-01

    We present the idea of using potential infringements on annual allowable harvest targets as an approach to estimate threats from invasive species to the forest products sector. The approach uses present-day harvest levels as a reference level to estimate when and where the impact of a nonnative forest pest could become economically damaging. We use a generic model that simulates spread and damage by nonnative invasive species, basic harvest and forest growth through time. The concept is illustrated with a case study of a new nonnative invasive pest, Sirex noctilio Fabricius on pine resources in eastern Canada. Impacts of invasion on wood supply, in particular, the point at which present-day harvest levels are not attainable, were identified for 77 non-overlapping geographical regions that delimit the primary wood supply areas around large mills and wood processing facilities in eastern Canada. The results identify the minimum area of a pest outbreak that could trigger harvest shortages (approximately 12.5-14 M ha of pine forests in Ontario and Quebec). Beyond this level, the amount of host resource available for harvesting in any given year declines rapidly. The failure to sustain broad-scale harvest targets may be an attractive and intuitive indicator for policy makers and regulators interested in developing control and "slow-the-spread" programs for non-native forest pests.

  18. Risk assessment of failure modes of gas diffuser liner of V94.2 siemens gas turbine by FMEA method

    NASA Astrophysics Data System (ADS)

    Mirzaei Rafsanjani, H.; Rezaei Nasab, A.

    2012-05-01

    Failure of welding connection of gas diffuser liner and exhaust casing is one of the failure modes of V94.2 gas turbines which are happened in some power plants. This defect is one of the uncertainties of customers when they want to accept the final commissioning of this product. According to this, the risk priority of this failure evaluated by failure modes and effect analysis (FMEA) method to find out whether this failure is catastrophic for turbine performance and is harmful for humans. By using history of 110 gas turbines of this model which are used in some power plants, the severity number, occurrence number and detection number of failure determined and consequently the Risk Priority Number (RPN) of failure determined. Finally, critically matrix of potential failures is created and illustrated that failure modes are located in safe zone.

  19. 30 CFR 218.40 - Assessments for incorrect or late reports and failure to report.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... INTERIOR MINERALS REVENUE MANAGEMENT COLLECTION OF MONIES AND PROVISION FOR GEOTHERMAL CREDITS AND... MMS by the designated due date for geothermal, solid minerals, and Indian oil and gas leases. (b) An... geothermal, solid minerals, and Indian oil and gas leases. (c) For purpose of assessments discussed in...

  20. Using Curriculum-Based Measurement To Prevent Failure and Assess Learning in the Content Areas.

    ERIC Educational Resources Information Center

    Busch, Todd W.; Espin, Christine A.

    2003-01-01

    This article describes a curriculum-based measure, vocabulary matching, that can be used to assess the performance of students with reading difficulties in the content areas. Data showing the validity and reliability of vocabulary matching as a measure of performance in the content areas are included. A case study illustrates the use of vocabulary…

  1. 30 CFR 1218.40 - Assessments for incorrect or late reports and failure to report.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... and gas leases. (c) For purpose of assessments discussed in this section, a report is defined as... ENFORCEMENT, DEPARTMENT OF THE INTERIOR Natural Resources Revenue COLLECTION OF MONIES AND PROVISION FOR... not received by Office of Natural Resources Revenue (ONRR) by the designated due date for...

  2. Root-cause analysis and health failure mode and effect analysis: two leading techniques in health care quality assessment.

    PubMed

    Shaqdan, Khalid; Aran, Shima; Daftari Besheli, Laleh; Abujudeh, Hani

    2014-06-01

    In this review article, the authors provide a detailed series of guidelines for effectively performing root-cause analysis (RCA) and health failure mode and effect analysis (HFMEA). RCA is a retrospective approach used to ascertain the "root cause" of a problem that has already occurred, whereas HFMEA is a prospective risk assessment tool whose aim is to recognize risks to patient safety. RCA and HFMEA are used for the prevention of errors or recurring errors to create a safer workplace, maintain high standards in health care quality, and incorporate time-saving and cost-saving modifications to favorably affect the patient care environment. The principles and techniques provided here should allow reviewers to better understand the features of RCA and HFMEA and how to apply these processes appropriately. These principles include how to organize a team, identify root causes, seed out proximate causes, graphically describe the process, conduct a hazard analysis, and develop and implement potential action plans.

  3. Wall shear stress assessment in the common carotid artery of end-stage renal failure patients.

    PubMed

    Samijo, S K; Barkhuysen, R; Willigers, J M; Leunissen, K M L; Ledoux, L A F; Kitslaar, P J E H M; Hoeks, A P G

    2002-01-01

    Under physiological circumstances in the common carotid artery (CCA), mean wall shear stress (WSS), defined as mean wall shear rate (WSR) times local whole blood viscosity (WBV), is maintained at approximately 1.5 Pa. In patients with end-stage renal failure (ESRF) whole blood viscosity is low and it is not unlikely that mean WSS is lower in these patients than in control subjects. Moreover, hemodialysis causes an acute increase in blood viscosity with possible effects on WSS. In this study WSS in the CCA was determined with the Shear Rate Estimating System, an apparatus based on ultrasound, in ESRF patients (n = 13) and in presumed healthy age- and sex-matched control subjects (n = 13). Prior to hemodialysis, mean WSS (0.67 +/- 0.23 Pa) was significantly lower (p < 0.05) in patients with ESRF, due to both a lower WBV (2.80 +/- 0.52 mPa.s) and mean WSR (271 +/- 109 s(-1)), than in the control subjects (mean WSS: 1.24 +/- 0.20 Pa; WBV: 3.20 +/- 0.29 mPa.s; WSR: 387 +/- 51 s(-1)). Hemodialysis induced an increase in WBV (up to 3.71 +/- 1.54 mPa.s, p < 0.01), but mean WSS did not change significantly due to a reciprocal decrease in mean wall shear rate. These findings demonstrate that WSS is lower in hemodialysis patients than in control subjects, and that mean WSS is maintained at this low level despite an acute change in blood viscosity.

  4. Risk assessment for incident heart failure in individuals with atrial fibrillation

    PubMed Central

    Schnabel, Renate B.; Rienstra, Michiel; Sullivan, Lisa M.; Sun, Jenny X.; Moser, Carlee B.; Levy, Daniel; Pencina, Michael J.; Fontes, João D.; Magnani, Jared W.; McManus, David D.; Lubitz, Steven A.; Tadros, Thomas M.; Wang, Thomas J.; Ellinor, Patrick T.; Vasan, Ramachandran S.; Benjamin, Emelia J.

    2013-01-01

    Background Atrial fibrillation (AF) is a strong risk factor for heart failure (HF); HF onset in patients with AF is associated with increased morbidity and mortality. Risk factors that predict HF in individuals with AF in the community are not well established. Methods and results We examined clinical variables related to the 10-year incidence of HF in 725 individuals (mean 73.3 years, 45% women) with documented AF in the Framingham Heart Study. Event rates for incident HF (n = 161, 48% in women) were comparable in women (4.30 per 100 person-years) and men (3.34 per 100 person-years). Age, body mass index, ECG LV hypertrophy, diabetes, significant murmur, and history of myocardial infarction were positively associated with incident HF in multivariable models (C-statistic 0.71; 95% confidence interval 0.67–0.75). We developed a risk algorithm for estimating absolute risk of HF in AF patients with good model fit and calibration (adjusted calibration χ2 statistic 7.29; Pχ2 = 0.61). Applying the algorithm, 47.6% of HF events occurred in the top tertile in men compared with 13.1% in the bottom tertile, and 58.4% in women in the upper tertile compared with 18.2% in the lowest category. For HF type, women had a non-significantly higher incidence of HF with preserved EF compared with men. Conclusions We describe advancing age, LV hypertrophy, body mass index, diabetes, significant heart murmur, and history of myocardial infarction as clinical predictors of incident HF in individuals with AF. A risk algorithm may help identify individuals with AF at high risk of developing HF. PMID:23594831

  5. A micromechanical model for the failure and damage assessment of woven composites

    NASA Astrophysics Data System (ADS)

    Abdelrahman, Wael Gamal Eldin

    A micromechanical model is advanced in order to study the stress transfer and associated damage and failure in classes of conventional and textile type fibrous composites. Unidirectionally reinforced matrix with straight and undulated fibers define the repeating constructing cell for conventional and textile composites, respectively. Starting with the case of straight reinforcement, we approximate and model the actual discrete composite as a concentric cylindrical system. For axisymmetric loading, and upon adopting some appropriate restrictions on the radial behavior of some field quantities, an elasticity-based procedure reduces the two-dimensional field equations, which hold in both fiber and matrix components together with the appropriate interface, symmetry and boundary conditions, to a quasi-one-dimensional system. This analysis is further extended to cases involving undulated fibers. Based upon local directions (slopes) of the undulated fibers, the linear transformation is used to obtain local stress distributions along the undulated fibers. The total stress field is found to be combinations of these local stresses and the inherent contributions obtained from the transformations of the normal loads along the undulated directions in the absence of reinforcement. This simple system retains total account of the system's physics and presents itself in the form of coupled partial differential equations in the longitudinal displacements and stresses of both the fiber and matrix components. According to this model, damage is simulated in the form of stress free boundary conditions. Perpetuation of damage is based upon the maximum normal stress criterion. The adverse effect of such damage on the stiffness properties of the composite is predicted. Results show the favorable effect of undulation in decreasing the rate of property degradation with increasing damage. The model is quite general and has been applied to several situations. These include response to static

  6. Application of the Sequential Organ Failure Assessment Score to predict outcome in critically ill dogs: preliminary results.

    PubMed

    Ripanti, D; Dino, G; Piovano, G; Farca, A

    2012-08-01

    In human medicine the Sequential Organ Failure Assessment (SOFA) score is one of the most commonly organ dysfunction scoring systems used to assess critically ill patients and to predict the outcome in Intensive Care Units (ICUs). It is composed of scores from six organ systems (respiratory, cardiovascular, hepatic, coagulation, renal, and neurological) graded according to the degree of the dysfunction. The aim of the current study was to describe the applicability of the SOFA score in assessing the outcome of critically ill dogs. A total of 45 dogs admitted to the ICU was enrolled. Among these, 40 dogs completed the study: 50 % survived and left the veterinary clinic. The SOFA score was computed for each dog every 24 hours for the first 3 days of ICU stay, starting on the day of admission. A statistically significant correlation between SOFA score and death or survival was found. Most of the dogs showing an increase of the SOFA score in the first 3 days of hospitalization died, whereas the dogs with a decrease of the score survived. These results suggest that the SOFA score system could be considered a useful indicator of prognosis in ICUs hospitalized dogs.

  7. Australia's pesticide environmental risk assessment failure: the case of diuron and sugarcane.

    PubMed

    Holmes, Glen

    2014-11-15

    In November 2012, the Australian Pesticide and Veterinary Medicines Authority (APVMA) concluded a 12 year review of the PSII herbicide diuron. One of the primary concerns raised during the review was the potential impact on aquatic ecosystems, particularly in the catchments draining to the Great Barrier Reef. The environmental risk assessment process used by the APVMA utilised a runoff risk model developed and validated under European farming conditions. However, the farming conditions in the sugarcane regions of the Great Barrier Reef catchments have environmental parameters beyond the currently validated bounds of the model. The use of the model to assess environmental risk in these regions is therefore highly inappropriate, demonstrating the pitfalls of a one size fits all approach.

  8. Incorporating cumulative effects into environmental assessments of mariculture: Limitations and failures of current siting methods

    SciTech Connect

    King, Sarah C. Pushchak, Ronald

    2008-11-15

    Assessing and evaluating the cumulative impacts of multiple marine aquaculture facilities has proved difficult in environmental assessment. A retrospective review of 23 existing mariculture farms in southwestern New Brunswick was conducted to determine whether cumulative interactions would have justified site approvals. Based on current scientific evidence of cumulative effects, six new criteria were added to a set of far-field impacts and other existing criteria were expanded to include regional and cumulative environmental impacts in Hargrave's [Hargrave BT. A traffic light decision system for marine finfish aquaculture siting. Ocean Coast Manag 2002; 45:215-35.] Traffic Light Decision Support System (DSS) presently used in Canadian aquaculture environmental assessments. Before mitigation, 19 of the 23 sites failed the amended set of criteria and after considering mitigation, 8 sites failed. Site and ecosystem indices yielded varying site acceptability scores; however, many sites would not have been approved if siting decisions had been made within a regional management framework and cumulative impact criteria were considered in the site evaluation process.

  9. Novel in vitro and in vivo neural interfaces: normal and accelerated failure assessment.

    PubMed

    Otto, Kevin; Williams, Justin

    2012-01-01

    Neural implantation of devices and the subsequent tissue response are complex and cascading physical and biological phenomena. Creation of reliable neural interfaces remains a significant challenge. Penetrating central nervous system interfaces persist as the most challenging to realize but continue to be the most attractive because of the information bandwidth advantages they provide. This rich information source is essential for achieving next-generation prosthetic control. Specific challenges of penetrating central nervous system interfaces arise because of the reactive tissue response to the initial injury due to device insertion as well as the continued response due to device indwelling. These responses consist of biochemical signaling events, microglial activation, and astrogliotic cell reorganization that result in biophysical changes of the tissue near the implanted device and finally, electrophysiological neural cell/signal loss (Figure 1). The ultimate realization of reliable penetrating neural interfaces will require careful science and engineering approaches incorporating knowledge of relevant and critical biological, physical, and chemical factors, especially their interrelationship. In this article, we describe a comprehensive strategy to assess the reliability of penetrating central neural interfaces based on the biology and pathology of the injury and indwelling tissue responses. Our strategy involves a parallel, self-informing approach by simultaneous development of new in vitro and in vivo assessment techniques as well as using these state-of-the-art techniques to conduct accelerated lifetime assessments of neural interface degradation.

  10. Acute renal failure requiring renal replacement therapy in the intensive care unit: impact on prognostic assessment for shared decision making.

    PubMed

    Johnson, Robert F; Gustin, Jillian

    2011-07-01

    A 69-year-old female was receiving renal replacement therapy (RRT) for acute renal failure (ARF) in an intensive care unit (ICU). Consultation was requested from the palliative medicine service to facilitate a shared decision-making process regarding goals of care. Clinician responsibility in shared decision making includes the formulation and expression of a prognostic assessment providing the necessary perspective for a spokesperson to match patient values with treatment options. For this patient, ARF requiring RRT in the ICU was used as a focal point for preparing a prognostic assessment. A prognostic assessment should include the outcomes of most importance to a discussion of goals of care: mortality risk and survivor functional status, in this case including renal recovery. A systematic review of the literature was conducted to document published data regarding these outcomes for adult patients receiving RRT for ARF in the ICU. Forty-one studies met the inclusion criteria. The combined mean values for short-term mortality, long-term mortality, renal-function recovery of short-term survivors, and renal-function recovery of long-term survivors were 51.7%, 68.6%, 82.0%, and 88.4%, respectively. This case example illustrates a process for formulating and expressing a prognostic assessment for an ICU patient requiring RRT for ARF. Data from the literature review provide baseline information that requires adjustment to reflect specific patient circumstances. The nature of the acute primary process, comorbidities, and severity of illness are key modifiers. Finally, the prognostic assessment is expressed during a family meeting using recommended principles of communication.

  11. Temporal Causal Diagrams for Diagnosing Failures in Cyber Physical Systems

    DTIC Science & Technology

    2014-10-02

    Guo, W., Wen, F., Ledwich, G., Liao, Z., He, X., & Liang, J. (2010). An Analytic Model for Fault Diagnosis in Power Systems Considering Malfunctions...IEEE Transactions on, 19(2), 524–532. Lin, X., Ke, S., Li, Z., Weng, H., & Han, X. (2010). A Fault Diagnosis Method of Power Systems Based on...On Control System Technology, 4(2), 105–124. Sekine, Y., Akimoto, Y., Kunugi, M., Fukui, C., & Fukui, S. (2002). Fault diagnosis of power systems

  12. Risk assessment of component failure modes and human errors using a new FMECA approach: application in the safety analysis of HDR brachytherapy.

    PubMed

    Giardina, M; Castiglia, F; Tomarchio, E

    2014-12-01

    Failure mode, effects and criticality analysis (FMECA) is a safety technique extensively used in many different industrial fields to identify and prevent potential failures. In the application of traditional FMECA, the risk priority number (RPN) is determined to rank the failure modes; however, the method has been criticised for having several weaknesses. Moreover, it is unable to adequately deal with human errors or negligence. In this paper, a new versatile fuzzy rule-based assessment model is proposed to evaluate the RPN index to rank both component failure and human error. The proposed methodology is applied to potential radiological over-exposure of patients during high-dose-rate brachytherapy treatments. The critical analysis of the results can provide recommendations and suggestions regarding safety provisions for the equipment and procedures required to reduce the occurrence of accidental events.

  13. Telomere Length Assessment for Prediction of Organ Transplantation Outcome. Future or Failure: A Review of the Literature

    PubMed Central

    Kłoda, Karolina; Domański, Leszek; Mierzecki, Artur

    2017-01-01

    Telomeres are located at each end of eukaryotic chromosomes. Their functional role is genomic stability maintenance. The protective role of telomeres depends on various factors, including number of nucleotides repeats, telomere-binding proteins, and telomerase activity. Organ transplantation is the preferred replacement therapy in the case of chronic kidney disease and the only possibility of sustaining recipients’ life in the case of advanced liver failure. While the prevalence of acute rejection is constantly decreasing, prevention of transplanted organ long-term function loss is still challenging. It has been demonstrated that post-transplant stressors accelerate aging of the allografts manifested through telomere shortening. The aim of this paper was to evaluate the importance of telomere length assessment for prediction of organ transplantation outcome. Literature review included the 10 most important studies regarding linkage between allograft function and telomere erosion, including 2 of our own reports. Telomere length assessment is useful to predict organ transplantation outcome. The importance of telomere length as a prediction marker depends on the analyzed material. To obtain reliable results, both graft cells (donor material) and lymphocytes (recipient material) should be examined. In the case of kidney transplantation, assessment of telomere length in the early post-transplant period allows prediction of the long-term function of the transplanted organ. To increase the accuracy of transplantation outcome prediction, telomere length assessment should be combined with evaluation of other aging biomarkers, like CDKN2A (p16). Large-scale clinical studies regarding telomere length measurement, including genome wide association analysis introducing relevant genetic factors, are needed for the future. PMID:28076340

  14. An assessment of the state of the art in predicting the failure of ceramics: Final report

    SciTech Connect

    Boulet, J.A.M.

    1988-03-01

    The greatest weakness in existing design strategies for brittle fracture is in the narrow range of conditions for which the strategies are adequate. The primary reason for this weakness is the use of simplistic mechanical models of fracture processes and unverified statistical models of materials. To improve the design methodology, the models must first be improved. Specifically recommended research goals are: to develop models of cracks with realistic geometry under arbitrary stress states; to identify and model the most important relationships between fracture processes and microstructural features; to assess the technology available for acquiring statistical data on microstructure and flaw populations, and to establish the amount of data required for verification of statistical models; and to establish a computer-based fracture simulation that can incorporate a wide variety of mechanical and statistical models and crack geometries, as well as arbitrary stress states. 204 refs., 2 tabs.

  15. Mapping basin-wide subaquatic slope failure susceptibility as a tool to assess regional seismic and tsunami hazards

    NASA Astrophysics Data System (ADS)

    Strasser, Michael; Hilbe, Michael; Anselmetti, Flavio S.

    2010-05-01

    occurred. Comparison of reconstructed critical stability conditions with the known distribution of landslide deposits reveals minimum and maximum threshold conditions for slopes that failed or remained stable, respectively. The resulting correlations reveal good agreements and suggest that the slope stability model generally succeeds in reproducing past events. The basin-wide mapping of subaquatic slope failure susceptibility through time thus can also be considered as a promising paleoseismologic tool that allows quantification of past earthquake ground shaking intensities. Furthermore, it can be used to assess the present-day slope failure susceptibility allowing for identification of location and estimation of size of future, potentially tsunamigenic subaquatic landslides. The new approach presented in our comprehensive lake study and resulting conceptual ideas can be vital to improve our understanding of larger marine slope instabilities and related seismic and oceanic geohazards along formerly glaciated ocean margins and closed basins worldwide.

  16. Prognostic value of pulmonary congestion assessed by lung ultrasound imaging during heart failure hospitalisation: A two-centre cohort study

    PubMed Central

    Coiro, Stefano; Porot, Guillaume; Rossignol, Patrick; Ambrosio, Giuseppe; Carluccio, Erberto; Tritto, Isabella; Huttin, Olivier; Lemoine, Simon; Sadoul, Nicolas; Donal, Erwan; Zannad, Faiez; Girerd, Nicolas

    2016-01-01

    Pulmonary congestion assessed at discharge by lung ultrasonography predicts poor prognosis in heart failure (HF) patients. We investigated the association of B-lines with indices of hemodynamic congestion [BNP, E/e’, pulmonary systolic arterial pressure (PAPs)] in HF patients, and their prognostic value overall and according to concomitant atrial fibrillation (AF), reduced (≤40%) ejection fraction (EF), and timing of quantification during hospitalisation for heart failure (HHF). In 110 HHF patients, B-lines were highly discriminative of BNP >400 pg/ml (AUC ≥ 0.80 for all), and moderately discriminative of PAPs >50 mmHg (AUC = 0.68, 0.56 to 0.80); conversely, B-lines poorly discriminated average E/e’ ≥ 15, except at discharge. B-line count significantly predicted mid-term recurrent HHF or death (overall and in subgroups), regardless of AF status, EF, and timing of quantification during HHF (all p for interaction >0.10). regardless, B-lines ≥30 at discharge were most predictive of outcome (HR = 7.11, 2.06–24.48; p = 0.002) while B-lines ≥45 early during HHF were most predictive of outcome (HR = 9.20, 1.82–46.61; p = 0.007). Lung ultrasound was able to identify patients with high BNP levels, but not with increased E/e’, also showing a prognostic role regardless of AF status, EF or timing of quantification; best B-line cut-off appears to vary according to the timing of quantification during hospitalization. PMID:27995971

  17. A new Doppler method of assessing left ventricular ejection force in chronic congestive heart failure.

    PubMed

    Isaaz, K; Ethevenot, G; Admant, P; Brembilla, B; Pernot, C

    1989-07-01

    A noninvasive method using Doppler echocardiography was developed to determine the force exerted by the left ventricle in accelerating the blood into the aorta. The value of this new Doppler ejection index in the assessment of left ventricular (LV) performance was tested in 36 patients with chronic congestive heart disease undergoing cardiac catheterization and in 11 age-matched normal control subjects. The 36 patients were subgrouped into 3 groups based on angiographic ejection fraction (LV ejection fraction greater than 60, 41 to 60 and less than or equal to 40%). According to Newton's second law of motion (force = mass X acceleration), the LV ejection force was derived from the product of the mass of blood ejected during the acceleration time with the mean acceleration undergone during that time. In patients with LV ejection fraction less than or equal to 40%, LV ejection force, peak aortic velocity and mean acceleration were severely depressed when compared with the other groups (p less than 0.001). In patients with LV ejection fraction of 41 to 60%, LV ejection force was significantly reduced (22 +/- 3 kdynes) when compared with normal subjects (29 +/- 5 kdynes, p = 0.002) and with patients with LV ejection fraction greater than 60% (29 +/- 7 kdynes, p = 0.009); peak velocity and mean acceleration did not differ between these 3 groups. The LV ejection force showed a good linear correlation with LV ejection fraction (r = 0.86) and a better power fit (r = 0.91). Peak aortic blood velocity and mean acceleration showed less good linear correlations with LV ejection fraction (r = 0.73 and r = 0.66, respectively). The mass of blood ejected during the acceleration time also showed a weak linear correlation with LV ejection fraction (r = 0.64). An LV ejection force less than 20 kdynes was associated with a depressed LV performance (LV ejection fraction less than 50%) with 91% sensitivity and 90% specificity. Thus, these findings suggest that LV ejection force is a new

  18. Assessment of formulation robustness for nano-crystalline suspensions using failure mode analysis or derisking approach.

    PubMed

    Nakach, Mostafa; Authelin, Jean-René; Voignier, Cecile; Tadros, Tharwat; Galet, Laurence; Chamayou, Alain

    2016-06-15

    The small particle size of nano-crystalline suspensions can be responsible for their physical instability during drug product preparation (downstream processing), storage and administration. For that purpose, the commercial formulation needs to be sufficiently robust to various triggering conditions, such as ionic strength, shear rate, wetting/dispersing agent desorption by dilution, temperature and pH variation. In our previous work we described a systematic approach to select the suitable wetting/dispersant agent for the stabilization of nano-crystalline suspension. In this paper, we described the assessment of the formulation robustness (stabilized using a mixture of sodium dodecyl sulfate (SDS) and polyvinylpyrrolidone (PVP) and) by measuring the rate of perikinetic (diffusion-controlled) and orthokinetic (shear-induced) aggregation as a function of ionic strength, temperature, pH and dilution. The results showed that, using the SDS/PVP system, the critical coagulation concentration is about five times higher than that observed in the literature for suspension colloidaly stable at high concentration. The nano-suspension was also found to be very stable at ambient temperature and at different pH conditions. Desorption test confirmed the high affinity between API and wetting/dispersing agent. However, the suspension undergoes aggregation at high temperature due to the desorption of the wetting/dispersing agent and disaggregation of SDS micelles. Furthermore, aggregation occurs at very high shear rate (orhokinetic aggregation) by overcoming the energy barrier responsible for colloidal stability of the system.

  19. Voronoi Diagrams and Spring Rain

    ERIC Educational Resources Information Center

    Perham, Arnold E.; Perham, Faustine L.

    2011-01-01

    The goal of this geometry project is to use Voronoi diagrams, a powerful modeling tool across disciplines, and the integration of technology to analyze spring rainfall from rain gauge data over a region. In their investigation, students use familiar equipment from their mathematical toolbox: triangles and other polygons, circumcenters and…

  20. Evaluation of site-site bridge diagrams for molecular fluids

    NASA Astrophysics Data System (ADS)

    Vatamanu, J.; Cann, N. M.

    2004-10-01

    The presence of bridge functions in formally exact integral equation theories is the primary obstacle preventing the extraction of exact fluid structure from these theories. The bridge functions are typically neglected but in many fluids their impact may be significant. Each bridge function can be subdivided into bridge diagrams, which are well defined but difficult to evaluate. The calculation of bridge diagrams for the Chandler-Silbey-Ladanyi (CSL) integral equation theory [D. Chandler, R. Silbey, and B. Ladanyi, Mol. Phys. 46, 1335 (1982)] is the subject of this paper. In particular, we evaluate the diagrams required to yield an exact theory up to the first power in density [O(ρ1)] and provide algorithms that remain feasible for any molecule. Further, the bridge diagrams are evaluated and compared with the f-bond and h-bond formulations. Exact bridge diagrams are numerically evaluated for several chiral molecules, for two polar dimers, and for SPC/E water [W. L. Jorgensen, J. Chandrasekhar, J. D. Madura, R. W. Impey, and M. L. Klein, J. Chem. Phys. 79, 926 (1983)]. The quality of the diagrams is assessed in two ways: First, the predicted interatomic distributions are compared with those obtained from Monte Carlo simulations. Second, the connectivity constraints are evaluated and the errors in satisfying these exact relationships are compared for the f-bond and h-bond formulations. For apolar fluids, a clear improvement in CSL theory is evident with the inclusion of O(ρ0) and O(ρ1) diagrams. In contrast, for polar fluids, the inclusion of bridge diagrams does not lead to improvement in the structural predictions.

  1. Generalized discriminant analysis for congestive heart failure risk assessment based on long-term heart rate variability.

    PubMed

    Shahbazi, Fatemeh; Asl, Babak Mohammadzadeh

    2015-11-01

    The aims of this study are summarized in the following items: first, to investigate the class discrimination power of long-term heart rate variability (HRV) features for risk assessment in patients suffering from congestive heart failure (CHF); second, to introduce the most discriminative features of HRV to discriminate low risk patients (LRPs) and high risk patients (HRPs), and third, to examine the influence of feature dimension reduction in order to achieve desired accuracy of the classification. We analyzed two public Holter databases: 12 data of patients suffering from mild CHF (NYHA class I and II), labeled as LRPs and 32 data of patients suffering from severe CHF (NYHA class III and IV), labeled as HRPs. A K-nearest neighbor classifier was used to evaluate the performance of feature set in the classification. Moreover, to reduce the number of features as well as the overlap of the samples of two classes in feature space, we used generalized discriminant analysis (GDA) as a feature extraction method. By applying GDA to the discriminative nonlinear features, we achieved sensitivity and specificity of 100% having the least number of features. Finally, the results were compared with other similar conducted studies regarding the performance of feature selection procedure and classifier besides the number of features used in training.

  2. Hero's journey in bifurcation diagram

    NASA Astrophysics Data System (ADS)

    Monteiro, L. H. A.; Mustaro, P. N.

    2012-06-01

    The hero's journey is a narrative structure identified by several authors in comparative studies on folklore and mythology. This storytelling template presents the stages of inner metamorphosis undergone by the protagonist after being called to an adventure. In a simplified version, this journey is divided into three acts separated by two crucial moments. Here we propose a discrete-time dynamical system for representing the protagonist's evolution. The suffering along the journey is taken as the control parameter of this system. The bifurcation diagram exhibits stationary, periodic and chaotic behaviors. In this diagram, there are transition from fixed point to chaos and transition from limit cycle to fixed point. We found that the values of the control parameter corresponding to these two transitions are in quantitative agreement with the two critical moments of the three-act hero's journey identified in 10 movies appearing in the list of the 200 worldwide highest-grossing films.

  3. Quantum Dimer Model: Phase Diagrams

    NASA Astrophysics Data System (ADS)

    Goldstein, Garry; Chamon, Claudio; Castelnovo, Claudio

    We present new theoretical analysis of the Quantum Dimer Model. We study dimer models on square, cubic and triangular lattices and we reproduce their phase diagrams (which were previously known only numerically). We show that there are several types of dimer liquids and solids. We present preliminary analysis of several other models including doped dimers and planar spin ice, and some results on the Kagome and hexagonal lattices.

  4. Phase diagram of crushed powders

    NASA Astrophysics Data System (ADS)

    Bodard, Sébastien; Jalbaud, Olivier; Saurel, Richard; Burtschell, Yves; Lapebie, Emmanuel

    2016-12-01

    Compression of monodisperse powder samples in quasistatic conditions is addressed in a pressure range such that particles fragmentation occurs while the solid remains incompressible (typical pressure range of 1-300 MPa for glass powders). For a granular bed made of particles of given size, the existence of three stages is observed during compression and crush up. First, classical compression occurs and the pressure of the granular bed increases along a characteristic curve as the volume decreases. Then, a critical pressure is reached for which fragmentation begins. During the fragmentation process, the granular pressure stays constant in a given volume range. At the end of this second stage, 20%-50% of initial grains are reduced to finer particles, depending on the initial size. Then the compression undergoes the third stage and the pressure increases along another characteristic curve, in the absence of extra fragmentation. The present paper analyses the analogies between the phase transition in liquid-vapour systems and powder compression with crush-up. Fragmentation diagram for a soda lime glass is determined by experimental means. The analogues of the saturation pressure and latent heat of phase change are determined. Two thermodynamic models are then examined to represent the crush-up diagram. The first one uses piecewise functions while the second one is of van der Waals type. Both equations of state relate granular pressure, solid volume fraction, and initial particle diameter. The piecewise functions approach provides reasonable representations of the phase diagram while the van der Waals one fails.

  5. Causal diagrams in systems epidemiology

    PubMed Central

    2012-01-01

    Methods of diagrammatic modelling have been greatly developed in the past two decades. Outside the context of infectious diseases, systematic use of diagrams in epidemiology has been mainly confined to the analysis of a single link: that between a disease outcome and its proximal determinant(s). Transmitted causes ("causes of causes") tend not to be systematically analysed. The infectious disease epidemiology modelling tradition models the human population in its environment, typically with the exposure-health relationship and the determinants of exposure being considered at individual and group/ecological levels, respectively. Some properties of the resulting systems are quite general, and are seen in unrelated contexts such as biochemical pathways. Confining analysis to a single link misses the opportunity to discover such properties. The structure of a causal diagram is derived from knowledge about how the world works, as well as from statistical evidence. A single diagram can be used to characterise a whole research area, not just a single analysis - although this depends on the degree of consistency of the causal relationships between different populations - and can therefore be used to integrate multiple datasets. Additional advantages of system-wide models include: the use of instrumental variables - now emerging as an important technique in epidemiology in the context of mendelian randomisation, but under-used in the exploitation of "natural experiments"; the explicit use of change models, which have advantages with respect to inferring causation; and in the detection and elucidation of feedback. PMID:22429606

  6. Scheil-Gulliver Constituent Diagrams

    NASA Astrophysics Data System (ADS)

    Pelton, Arthur D.; Eriksson, Gunnar; Bale, Christopher W.

    2017-03-01

    During solidification of alloys, conditions often approach those of Scheil-Gulliver cooling in which it is assumed that solid phases, once precipitated, remain unchanged. That is, they no longer react with the liquid or with each other. In the case of equilibrium solidification, equilibrium phase diagrams provide a valuable means of visualizing the effects of composition changes upon the final microstructure. In the present study, we propose for the first time the concept of Scheil-Gulliver constituent diagrams which play the same role as that in the case of Scheil-Gulliver cooling. It is shown how these diagrams can be calculated and plotted by the currently available thermodynamic database computing systems that combine Gibbs energy minimization software with large databases of optimized thermodynamic properties of solutions and compounds. Examples calculated using the FactSage system are presented for the Al-Li and Al-Mg-Zn systems, and for the Au-Bi-Sb-Pb system and its binary and ternary subsystems.

  7. Assessment of the risk of failure of high voltage substations due to environmental conditions and pollution on insulators.

    PubMed

    Castillo Sierra, Rafael; Oviedo-Trespalacios, Oscar; Candelo, John E; Soto, Jose D

    2015-07-01

    Pollution on electrical insulators is one of the greatest causes of failure of substations subjected to high levels of salinity and environmental pollution. Considering leakage current as the main indicator of pollution on insulators, this paper focuses on establishing the effect of the environmental conditions on the risk of failure due to pollution on insulators and determining the significant change in the magnitude of the pollution on the insulators during dry and humid periods. Hierarchical segmentation analysis was used to establish the effect of environmental conditions on the risk of failure due to pollution on insulators. The Kruskal-Wallis test was utilized to determine the significant changes in the magnitude of the pollution due to climate periods. An important result was the discovery that leakage current was more common on insulators during dry periods than humid ones. There was also a higher risk of failure due to pollution during dry periods. During the humid period, various temperatures and wind directions produced a small change in the risk of failure. As a technical result, operators of electrical substations can now identify the cause of an increase in risk of failure due to pollution in the area. The research provides a contribution towards the behaviour of the leakage current under conditions similar to those of the Colombian Caribbean coast and how they affect the risk of failure of the substation due to pollution.

  8. Longitudinal load and cascading failure risk assessment (CASE): Bonneville Power Administration`s 230/500-kV Longview-Olympia transmission line. Final report

    SciTech Connect

    Ostendorp, M.

    1998-12-01

    The Electric Power Research Institute`s (EPRI) Cascading Failure Risk Assessment (CASE) methodology was used to determine extreme event, unbalanced loads on Bonneville Power Administration`s (BPA) 230/500-kV, single circuit, Longview-Olympia transmission line and to identify the cascading potential of the line under five different loading conditions. More specifically, BPA wanted to evaluate the cascading potential of the Type 2L, Type 2A1, and Type 238M tangent structures which comprise a significant portion of the line. While other cascading assessment methods primarily focus on the magnitude of the unbalanced loads acting on the first structure from the initiating event, EPRI`s CASE method incorporates the dynamic response and damping characteristics of the transmission line to determine the unbalanced longitudinal loads at any structure away from the initiating failure event. The CASE application constituted an investigation into the nature of the extreme loads that are expected to occur on the 230/500-kV Longview-Olympia transmission line during a cascading failure and the corresponding dynamic response. The goals of the investigation were: to quantify unbalanced longitudinal loads acting on structures adjacent to the broken insulator, shield wire, or conductor failure as well as down-line structures; and to assess the cascading potential of the Longview-Olympia transmission line by considering the energy dissipation at successive spans and supports. The results of the CASE method showed that BPA`s longitudinal loading criteria for the Type 2L, 2A1, and 238 M lattice towers satisfy BPA`s containment failure design philosophy with the addition of fiber optic cable. BPA`s longitudinal loading criteria applied simultaneously with extreme ice or wind does not provide adequate strength to prevent a cascade of less than ten towers.

  9. Longitudinal load and cascading failure risk assessment (CASE): Tennessee Valley Authority`s 161-kV Lowndes-West Point transmission line. Final report

    SciTech Connect

    Ostendorp, M.

    1998-03-01

    The Electric Power Research Institute`s (EPRI) Cascading Failure Risk Assessment (CASE) methodology was used to determine extreme event, unbalanced loads on Tennessee Valley Authority`s (TVA) 161-kV, single circuit, Lowndes-West Point transmission line and to identify the cascading potential of the line under five different loading conditions. More specifically, TVA wanted to evaluate the cascading potential of the Type HS-1G and BHS-1G tangent structures which comprise the majority of the line. While other cascading assessment methods primarily focus on the magnitude of the unbalanced loads acting on the first structure from the initiating event, EPRI`s CASE method incorporates the dynamic response and damping characteristics of the transmission line to determine the unbalanced longitudinal loads at any structure away from the initiating failure event. The CASE application constituted an investigation into the nature of the extreme loads that are expected to occur on the 161-kV Lowndes-West Point transmission line during a cascading failure and the corresponding dynamic response. The goals of the investigation were: to quantify unbalanced longitudinal loads acting on structures adjacent to the broken insulator, shield wire, or conductor failure as well as down-line structures; to assess the cascading potential of the Lowndes-West Point transmission line by considering the energy dissipation at successive spans and supports. The results of the CASE method indicate that the lack of longitudinal strength of the Type HS-1G and BHS-1G steel pole H-frame coupled with the dynamic characteristics of the Lowndes-West Point line was likely to result in a cascading failure for the more severe initiating event and load case combinations.

  10. Diagram, a Learning Environment for Initiation to Object-Oriented Modeling with UML Class Diagrams

    ERIC Educational Resources Information Center

    Py, Dominique; Auxepaules, Ludovic; Alonso, Mathilde

    2013-01-01

    This paper presents Diagram, a learning environment for object-oriented modelling (OOM) with UML class diagrams. Diagram an open environment, in which the teacher can add new exercises without constraints on the vocabulary or the size of the diagram. The interface includes methodological help, encourages self-correcting and self-monitoring, and…

  11. Phase diagrams of polyelectrolyte solutions

    NASA Astrophysics Data System (ADS)

    Mahdi, Khaled A.

    We study the phase diagram of polyelectrolyte solutions in salt and salt-free environments. We examine the phase behavior of polyelectrolyte solutions, in the semidilute regime, using different physical models, namely the Random Phase Approximation (RPA) and the cross-linked model. In the RPA, we calculate the electrostatic free energy by summing all the fluctuations of the chains and all present ionic species. Within this approximation, the phase diagrams of salt-free polyelectrolyte solutions show phase separation even without including short-range attractions or ion condensation. We find that the phase behavior of large chains resembles the phase diagram of polymer network solutions. That is, the equilibrium is established between a network phase and a chain-free phase. Upon the addition of salt, the dissociated ions increase the entropy of the system and overcome the energy from the electrostatic fluctuations. When the short-range attraction between monomers is included in the model, the free energy predicts phase segregation for all salt valences at high salt concentrations (1 mol/l and higher). The phenomenon is called salting-out and occurs simply because the addition of salt reduces the quality of the solvent and induces precipitation. However, phase segregation in the presence of multivalent ions in polyelectrolyte solutions occurs at low salt concentrations (less than 1 mol/l). We propose that this phase separation is due to polyions cross-linked by multivalent ions. We constructed a phenomenological two-state model to examine this phenomenon. The two phases coexisting in the solution are a network-like phase and a polymer-free phase. The polymer-free phase is modeled using Debye-Huckel theory. In the cross-linked phase, each condensed multivalent ion attracts an equal number of monomers creating a neutral cluster. The energy of the cluster is evaluated by a simple Coulombic energy. The bare monomer charges between the linkages are treated as line of

  12. A Comprehensive Structural Analysis Process for Failure Assessment in Aircraft Lap-Joint Mimics Using Multi-Modal Fusion of NDE Data (Preprint)

    DTIC Science & Technology

    2012-07-01

    modality . In order to address the limitations of FEM-based methods in their ability to predict fatigue, more specialized numerical modeling...AFRL-RX-WP-TP-2012-0350 A COMPREHENSIVE STRUCTURAL ANALYSIS PROCESS FOR FAILURE ASSESSMENT IN AIRCRAFT LAP-JOINT MIMICS USING MULTI- MODAL ...structural analysis process is presented that includes intra- and inter- modal NDE data fusion. The process includes defect detection, defect

  13. The Importance of Design in Learning from Node-Link Diagrams

    ERIC Educational Resources Information Center

    van Amelsvoort, Marije; van der Meij, Jan; Anjewierden, Anjo; van der Meij, Hans

    2013-01-01

    Diagrams organize by location. They give spatial cues for finding and recognizing information and for making inferences. In education, diagrams are often used to help students understand and recall information. This study assessed the influence of perceptual cues on reading behavior and subsequent retention. Eighty-two participants were assigned…

  14. Phase diagrams for sonoluminescing bubbles

    NASA Astrophysics Data System (ADS)

    Hilgenfeldt, Sascha; Lohse, Detlef; Brenner, Michael P.

    1996-11-01

    Sound driven gas bubbles in water can emit light pulses. This phenomenon is called sonoluminescence (SL). Two different phases of single bubble SL have been proposed: diffusively stable and diffusively unstable SL. We present phase diagrams in the gas concentration versus forcing pressure state space and also in the ambient radius versus gas concentration and versus forcing pressure state spaces. These phase diagrams are based on the thresholds for energy focusing in the bubble and two kinds of instabilities, namely (i) shape instabilities and (ii) diffusive instabilities. Stable SL only occurs in a tiny parameter window of large forcing pressure amplitude Pa˜1.2-1.5 atm and low gas concentration of less than 0.4% of the saturation. The upper concentration threshold becomes smaller with increased forcing. Our results quantitatively agree with experimental results of Putterman's UCLA group on argon, but not on air. However, air bubbles and other gas mixtures can also successfully be treated in this approach if in addition (iii) chemical instabilities are considered. All statements are based on the Rayleigh-Plesset ODE approximation of the bubble dynamics, extended in an adiabatic approximation to include mass diffusion effects. This approximation is the only way to explore considerable portions of parameter space, as solving the full PDEs is numerically too expensive. Therefore, we checked the adiabatic approximation by comparison with the full numerical solution of the advection diffusion PDE and find good agreement.

  15. Asteroseismology Across the HR Diagram

    NASA Astrophysics Data System (ADS)

    Thompson, M. J.; Cunha, M. S.; Monteiro, M. J. P. F. G.

    2003-05-01

    Ground-based observations have detected solar-like oscillations on Sun-like stars, and diagnostics similar to those used in helioseismology are now being used to test and constrain the physics and evolutionary state of these stars. Multi-mode oscillations are being observed in an abundance of other stars, including slowly pulsating B stars (SPB stars), delta-Scuti stars, Ap stars and the pulsating white dwarfs. New classes of pulsators continue to be discovered across the Herzsprung-Russell diagram. Yet the chances still to be faced to make asteroseismology across the HR diagram a reality are formidable. Observation, data analysis and theory all pose hard problems to be overcome. This book, reflecting the goal of the meeting, aims to facilitate a cross-fertilisation of ideas and approaches between fields covering different pulsators and with different areas of expertise. The book successfully covers most known types of pulsators, reflecting a highly productive and far reaching interchange of ideas which we believe is conveyed by the papers and posters published, making it a reference for researchers and postgraduate students working on stellar structure and evolution. Link: http://www.wkap.nl/prod/b/1-4020-1173-3

  16. Phase Diagrams of Nuclear Pasta

    NASA Astrophysics Data System (ADS)

    Caplan, Matthew; Horowitz, Chuck; Berry, Don; da Silva Schneider, Andre

    2016-03-01

    In the inner crust of neutrons stars, where matter is near the saturation density, protons and neutrons arrange themselves into complex structures called nuclear pasta. Early theoretical work predicted a simple graduated hierarchy of pasta phases, consisting of spheres, cylinders, slabs, and uniform matter with voids. Previous work has simulated these phases with a simple classical model and has shown that the formation of these structures is dependent on the temperature, density, and proton fraction. However, previous work only studied a limited range of these parameters due to computational limitations. Thanks to recent advances in computing it is now possible to survey the structure of nuclear pasta for a larger range of parameters. By simulating nuclear pasta with constant temperature and proton fraction in an expanding simulation volume we are able to study the phase transitions in nuclear pasta, and thus produce a set of phase diagrams. We report on these phase diagrams as well as newly identified phases of nuclear pasta and discuss their implications for neutron star observables.

  17. Failure mode and effects analysis based risk profile assessment for stereotactic radiosurgery programs at three cancer centers in Brazil

    SciTech Connect

    Teixeira, Flavia C.

    2016-01-15

    Purpose: The goal of this study was to evaluate the safety and quality management program for stereotactic radiosurgery (SRS) treatment processes at three radiotherapy centers in Brazil by using three industrial engineering tools (1) process mapping, (2) failure modes and effects analysis (FMEA), and (3) fault tree analysis. Methods: The recommendations of Task Group 100 of American Association of Physicists in Medicine were followed to apply the three tools described above to create a process tree for SRS procedure for each radiotherapy center and then FMEA was performed. Failure modes were identified for all process steps and values of risk priority number (RPN) were calculated from O, S, and D (RPN = O × S × D) values assigned by a professional team responsible for patient care. Results: The subprocess treatment planning was presented with the highest number of failure modes for all centers. The total number of failure modes were 135, 104, and 131 for centers I, II, and III, respectively. The highest RPN value for each center is as follows: center I (204), center II (372), and center III (370). Failure modes with RPN ≥ 100: center I (22), center II (115), and center III (110). Failure modes characterized by S ≥ 7, represented 68% of the failure modes for center III, 62% for center II, and 45% for center I. Failure modes with RPNs values ≥100 and S ≥ 7, D ≥ 5, and O ≥ 5 were considered as high priority in this study. Conclusions: The results of the present study show that the safety risk profiles for the same stereotactic radiotherapy process are different at three radiotherapy centers in Brazil. Although this is the same treatment process, this present study showed that the risk priority is different and it will lead to implementation of different safety interventions among the centers. Therefore, the current practice of applying universal device-centric QA is not adequate to address all possible failures in clinical processes at different

  18. Diagnostic accuracy of salivary creatinine, urea, and potassium levels to assess dialysis need in renal failure patients

    PubMed Central

    Bagalad, Bhavana S.; Mohankumar, K. P.; Madhushankari, G. S.; Donoghue, Mandana; Kuberappa, Puneeth Horatti

    2017-01-01

    Background: The prevalence of chronic renal failure is increasing because of increase in chronic debilitating diseases and progressing age of population. These patients experience accumulation of metabolic byproducts and electrolyte imbalance, which has harmful effects on their health. Timely hemodialysis at regular intervals is a life-saving procedure for these patients. Salivary diagnostics is increasingly used as an alternative to the traditional methods. Thus, the aim of the present study was to determine the diagnostic efficacy of saliva in chronic renal failure patients. Materials and Methods: This case–control study included 82 individuals, of which 41 were chronic renal failure patients and 41 were age- and sex-matched controls. Blood and saliva were collected and centrifuged. Serum and supernatant saliva were used for biochemical analysis. Serum and salivary urea, creatinine, sodium, potassium, calcium, and phosphorus were evaluated and correlated in chronic renal failure patients using unpaired t-test, Pearson's correlation coefficient, diagnostic validity tests, and receiver operative curve. Results: When compared to serum; salivary urea, creatinine, sodium, and potassium showed diagnostic accuracy of 93%, 91%, 73%, and 89%, respectively, based on the findings of study. Conclusion: It can be concluded that salivary investigation is a dependable, noninvasive, noninfectious, simple, and quick method for screening the mineral and metabolite values of high-risk patients and monitoring the renal failure patients.

  19. Respiratory Failure

    MedlinePlus

    Respiratory failure happens when not enough oxygen passes from your lungs into your blood. Your body's organs, ... brain, need oxygen-rich blood to work well. Respiratory failure also can happen if your lungs can' ...

  20. An assessment of BWR (boiling water reactor) Mark III containment challenges, failure modes, and potential improvements in performance

    SciTech Connect

    Schroeder, J.A.; Pafford, D.J.; Kelly, D.L.; Jones, K.R.; Dallman, F.J. )

    1991-01-01

    This report describes risk-significant challenges posed to Mark III containment systems by severe accidents as identified for Grand Gulf. Design similarities and differences between the Mark III plants that are important to containment performance are summarized. The accident sequences responsible for the challenges and the postulated containment failure modes associated with each challenge are identified and described. Improvements are discussed that have the potential either to prevent or delay containment failure, or to mitigate the offsite consequences of a fission product release. For each of these potential improvements, a qualitative analysis is provided. A limited quantitative risk analysis is provided for selected potential improvements. 21 refs., 5 figs., 46 tabs.

  1. Heart Failure

    MedlinePlus

    Heart failure is a condition in which the heart can't pump enough blood to meet the body's needs. Heart failure does not mean that your heart has stopped ... Tiredness and shortness of breath Common causes of heart failure are coronary artery disease, high blood pressure and ...

  2. Continuation of point clouds via persistence diagrams

    NASA Astrophysics Data System (ADS)

    Gameiro, Marcio; Hiraoka, Yasuaki; Obayashi, Ippei

    2016-11-01

    In this paper, we present a mathematical and algorithmic framework for the continuation of point clouds by persistence diagrams. A key property used in the method is that the persistence map, which assigns a persistence diagram to a point cloud, is differentiable. This allows us to apply the Newton-Raphson continuation method in this setting. Given an original point cloud P, its persistence diagram D, and a target persistence diagram D‧, we gradually move from D to D‧, by successively computing intermediate point clouds until we finally find a point cloud P‧ having D‧ as its persistence diagram. Our method can be applied to a wide variety of situations in topological data analysis where it is necessary to solve an inverse problem, from persistence diagrams to point cloud data.

  3. Phase diagrams for high Tc superconductors

    SciTech Connect

    Whitler, J.D.; Roth, R.S. NIST, Gaithersburg, MD )

    1991-01-01

    The phase diagrams of ternary and quaternary systems containing superconducting phases are presented, as are the phase diagrams of the associated binary systems. The diagrams are divided into two large groups: (1) alkaline earth-rare earth-copper-oxygen diagrams, and (2) alkaline earth-bismuth/lead-copper-oxygen diagrams. The first group includes BaO-REO-CuO systems followed by SrO-REO-CuO or Nd2O3-CeO-CuO systems. The second group includes systems related to the AE-Bi2O3-CuO and AE-PbO-CuO systems. The phase diagrams are accompanied by notes relating procedures used in the studies, results obtained, and comparisons with the results in the literature for the same system.

  4. Hubble's diagram and cosmic expansion

    PubMed Central

    Kirshner, Robert P.

    2004-01-01

    Edwin Hubble's classic article on the expanding universe appeared in PNAS in 1929 [Hubble, E. P. (1929) Proc. Natl. Acad. Sci. USA 15, 168–173]. The chief result, that a galaxy's distance is proportional to its redshift, is so well known and so deeply embedded into the language of astronomy through the Hubble diagram, the Hubble constant, Hubble's Law, and the Hubble time, that the article itself is rarely referenced. Even though Hubble's distances have a large systematic error, Hubble's velocities come chiefly from Vesto Melvin Slipher, and the interpretation in terms of the de Sitter effect is out of the mainstream of modern cosmology, this article opened the way to investigation of the expanding, evolving, and accelerating universe that engages today's burgeoning field of cosmology. PMID:14695886

  5. Phase diagram of Hertzian spheres

    NASA Astrophysics Data System (ADS)

    Pàmies, Josep C.; Cacciuto, Angelo; Frenkel, Daan

    2009-07-01

    We report the phase diagram of interpenetrating Hertzian spheres. The Hertz potential is purely repulsive, bounded at zero separation, and decreases monotonically as a power law with exponent 5/2, vanishing at the overlapping threshold. This simple functional describes the elastic interaction of weakly deformable bodies and, therefore, it is a reliable physical model of soft macromolecules, like star polymers and globular micelles. Using thermodynamic integration and extensive Monte Carlo simulations, we computed accurate free energies of the fluid phase and a large number of crystal structures. For this, we defined a general primitive unit cell that allows for the simulation of any lattice. We found multiple re-entrant melting and first-order transitions between crystals with cubic, trigonal, tetragonal, and hexagonal symmetries.

  6. Gravity on-shell diagrams

    NASA Astrophysics Data System (ADS)

    Herrmann, Enrico; Trnka, Jaroslav

    2016-11-01

    We study on-shell diagrams for gravity theories with any number of super-symmetries and find a compact Grassmannian formula in terms of edge variables of the graphs. Unlike in gauge theory where the analogous form involves only d log-factors, in gravity there is a non-trivial numerator as well as higher degree poles in the edge variables. Based on the structure of the Grassmannian formula for {N}=8 supergravity we conjecture that gravity loop amplitudes also possess similar properties. In particular, we find that there are only logarithmic singularities on cuts with finite loop momentum and that poles at infinity are present, in complete agreement with the conjecture presented in [1].

  7. Hubble's diagram and cosmic expansion.

    PubMed

    Kirshner, Robert P

    2004-01-06

    Edwin Hubble's classic article on the expanding universe appeared in PNAS in 1929 [Hubble, E. P. (1929) Proc. Natl. Acad. Sci. USA 15, 168-173]. The chief result, that a galaxy's distance is proportional to its redshift, is so well known and so deeply embedded into the language of astronomy through the Hubble diagram, the Hubble constant, Hubble's Law, and the Hubble time, that the article itself is rarely referenced. Even though Hubble's distances have a large systematic error, Hubble's velocities come chiefly from Vesto Melvin Slipher, and the interpretation in terms of the de Sitter effect is out of the mainstream of modern cosmology, this article opened the way to investigation of the expanding, evolving, and accelerating universe that engages today's burgeoning field of cosmology.

  8. Phase diagram of ammonium nitrate

    NASA Astrophysics Data System (ADS)

    Dunuwille, M.; Yoo, C. S.

    2014-05-01

    Ammonium Nitrate (AN) has often subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood -resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 17 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400 °C.

  9. Phase diagram of ammonium nitrate

    NASA Astrophysics Data System (ADS)

    Dunuwille, Mihindra; Yoo, Choong-Shik

    2013-12-01

    Ammonium Nitrate (AN) is a fertilizer, yet becomes an explosive upon a small addition of chemical impurities. The origin of enhanced chemical sensitivity in impure AN (or AN mixtures) is not well understood, posing significant safety issues in using AN even today. To remedy the situation, we have carried out an extensive study to investigate the phase stability of AN and its mixtures with hexane (ANFO-AN mixed with fuel oil) and Aluminum (Ammonal) at high pressures and temperatures, using diamond anvil cells (DAC) and micro-Raman spectroscopy. The results indicate that pure AN decomposes to N2, N2O, and H2O at the onset of the melt, whereas the mixtures, ANFO and Ammonal, decompose at substantially lower temperatures. The present results also confirm the recently proposed phase IV-IV' transition above 17 GPa and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400°C.

  10. Process Flow Diagrams for Training and Operations

    NASA Astrophysics Data System (ADS)

    Venter, Jacobus

    This paper focuses on the use of process flow diagrams for training first responders who execute search and seizure warrants at electronic crime scenes. A generic process flow framework is presented, and the design goals and layout characteristics of process flow diagrams are discussed. An evaluation of the process flow diagrams used in training courses indicates that they are beneficial to first responders performing searches and seizures, and they speed up investigations, including those conducted by experienced personnel.

  11. Influence Diagram Use With Respect to Technology Planning and Investment

    NASA Technical Reports Server (NTRS)

    Levack, Daniel J. H.; DeHoff, Bryan; Rhodes, Russel E.

    2009-01-01

    Influence diagrams are relatively simple, but powerful, tools for assessing the impact of choices or resource allocations on goals or requirements. They are very general and can be used on a wide range of problems. They can be used for any problem that has defined goals, a set of factors that influence the goals or the other factors, and a set of inputs. Influence diagrams show the relationship among a set of results and the attributes that influence them and the inputs that influence the attributes. If the results are goals or requirements of a program, then the influence diagram can be used to examine how the requirements are affected by changes to technology investment. This paper uses an example to show how to construct and interpret influence diagrams, how to assign weights to the inputs and attributes, how to assign weights to the transfer functions (influences), and how to calculate the resulting influences of the inputs on the results. A study is also presented as an example of how using influence diagrams can help in technology planning and investment. The Space Propulsion Synergy Team (SPST) used this technique to examine the impact of R&D spending on the Life Cycle Cost (LCC) of a space transportation system. The question addressed was the effect on the recurring and the non-recurring portions of LCC of the proportion of R&D resources spent to impact technology objectives versus the proportion spent to impact operational dependability objectives. The goals, attributes, and the inputs were established. All of the linkages (influences) were determined. The weighting of each of the attributes and each of the linkages was determined. Finally the inputs were varied and the impacts on the LCC determined and are presented. The paper discusses how each of these was accomplished both for credibility and as an example for future studies using influence diagrams for technology planning and investment planning.

  12. Origin and use of crystallization phase diagrams

    PubMed Central

    Rupp, Bernhard

    2015-01-01

    Crystallization phase diagrams are frequently used to conceptualize the phase relations and also the processes taking place during the crystallization of macromolecules. While a great deal of freedom is given in crystallization phase diagrams owing to a lack of specific knowledge about the actual phase boundaries and phase equilibria, crucial fundamental features of phase diagrams can be derived from thermodynamic first principles. Consequently, there are limits to what can be reasonably displayed in a phase diagram, and imagination may start to conflict with thermodynamic realities. Here, the commonly used ‘crystallization phase diagrams’ are derived from thermodynamic excess properties and their limitations and appropriate use is discussed. PMID:25760697

  13. Application of Failure Mode and Effect Analysis (FMEA) and cause and effect analysis in conjunction with ISO 22000 to a snails (Helix aspersa) processing plant; A case study.

    PubMed

    Arvanitoyannis, Ioannis S; Varzakas, Theodoros H

    2009-08-01

    Failure Mode and Effect Analysis (FMEA) has been applied for the risk assessment of snails manufacturing. A tentative approach of FMEA application to the snails industry was attempted in conjunction with ISO 22000. Preliminary Hazard Analysis was used to analyze and predict the occurring failure modes in a food chain system (snails processing plant), based on the functions, characteristics, and/or interactions of the ingredients or the processes, upon which the system depends. Critical Control points have been identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram, and fishbone diagram). In this work a comparison of ISO22000 analysis with HACCP is carried out over snails processing and packaging. However, the main emphasis was put on the quantification of risk assessment by determining the RPN per identified processing hazard. Sterilization of tins, bioaccumulation of heavy metals, packaging of shells and poisonous mushrooms, were the processes identified as the ones with the highest RPN (280, 240, 147, 144, respectively) and corrective actions were undertaken. Following the application of corrective actions, a second calculation of RPN values was carried out leading to considerably lower values (below the upper acceptable limit of 130). It is noteworthy that the application of Ishikawa (Cause and Effect or Tree diagram) led to converging results thus corroborating the validity of conclusions derived from risk assessment and FMEA. Therefore, the incorporation of FMEA analysis within the ISO22000 system of a snails processing industry is considered imperative.

  14. Non-Invasive Ventilation (NIV) and Homeostatic Model Assessment (HOMA) Index in Stable Chronic Obstructive Pulmonary Disease (COPD) Patients with Chronic Hypercapnic Respiratory Failure: A Pilot Study.

    PubMed

    Dimoulis, Andreas; Pastaka, Chaido; Tsolaki, Vasiliki; Tsilioni, Irini; Pournaras, Spyridon; Liakos, Nikolaos; Georgoulias, Panagiotis; Gourgoulianis, Konstantinos

    2015-08-01

    The effects of Non-invasive Ventilation (NIV) on Insulin Resistance (IR) in stable Chronic Obstructive Pulmonary Disease (COPD) patients have not been fully explored. The aim of this study was to assess the effects of NIV on IR and adiponectin levels during one year application of NIV in stable COPD patients with Chronic Hypercapnic Respiratory Failure. Twenty-five (25) stable COPD patients with Chronic Hypercapnic Respiratory Failure and with no self-reported comorbidities completed the study. NIV was administered in the spontaneous/timed mode via a full face mask using a bi-level positive airway pressure system. Spirometry, blood pressure, arterial blood gases, dyspnea, daytime sleepiness, serum fasting glucose and insulin levels were assessed. IR was assessed with the calculation of the Homeostatic Model Assessment (HOMA) index. Adiponectin was measured with radioimmunoassay. Study participants were re-evaluated on the first, third, sixth, ninth and twelfth month after the initial evaluation. There was a significant improvement in FEV1 values from the first month (34.1 ± 11.6% vs 37 ± 12.3%, p = 0.05). There was a significant decrease in IR by the ninth month of NIV use (3.4 ± 2.3 vs 2.2 ± 1.4, p < 0.0001), while adiponectin levels significantly improved from the first month of NIV use. Stepwise regression analysis revealed that baseline HOMA index was associated with paCO2 (β = 0.07 ± 0.02, p = 0.001), while baseline adiponectin levels were associated with FVC (β = 0.05 ± 0.02, p = 0.035) and the concentration of serum bicarbonate (HCO3-) (-β = 0.18 ± 0.06, p = 0.002). Insulin sensitivity and glucose metabolism as well as adiponectin levels improved along with the improvements in respiratory failure.

  15. Influence Diagrams as Decision-Making Tools for Pesticide Risk Management

    EPA Science Inventory

    The pesticide policy arena is filled with discussion of probabilistic approaches to assess ecological risk, however, similar discussions about implementing formal probabilistic methods in pesticide risk decision making are less common. An influence diagram approach is proposed f...

  16. Diagrams Showing Actions for Reducing Exposures to Polychlorinated Biphenyls (PCBs) in Indoor Building Environments

    EPA Pesticide Factsheets

    This diagram compliments the document, PCBs in Building Materials: Q's & A's, on how exposure to PCBs can be assessed and reduced in school buildings. It describes actions for reducing exposures to PCBs in indoor school building environments.

  17. Vesicle deformation by microtubules: A phase diagram

    NASA Astrophysics Data System (ADS)

    Emsellem, Virginie; Cardoso, Olivier; Tabeling, Patrick

    1998-10-01

    The experimental investigation of vesicles deformed by the growth of encapsulated microtubules shows that the axisymmetric morphologies can be classified into ovals, lemons, φ, cherries, dumbbells, and pearls. A geometrical phase diagram is established. Numerical minimization of the elastic energy of the membrane reproduces satisfactorily well the observed morphologies and the corresponding phase diagram.

  18. The morphological diagram of spinels

    SciTech Connect

    Ziolkowski, J.

    1996-02-01

    Catalytic anisotropy in mild oxidation reactions results from the varying activity of different crystal faces. Here, spinels exposing (100), (110), and (111) faces have been considered and their Curie-Wulff plots have been drawn, admitting that the relative G(hkl) surface free energies may change in a wide range as a function of composition, inversion, and segregation degree. The normalized free surface energies are defined as A = G(100)/G(111), B = G(110)/G(111), and C = G(111)/G(111) = 1 = const. This made it possible to construct bidimensional morphological diagrams (morphology = f(A,B) at C = const) in the exposed-face-type, solid-type, and exposure-percentage versions. Eleven morphological habits of grains have been identified, including (100)-cube, (110)-dodecahedron, (111)-hexagons, 18-hedron, 20-hedron, and up to 26-hedra bordered with (i) 6 (100)-octagons, 12 (110)-rectangles, and 8 (111)-hexagons, (ii) 6 (100)-squares, 12 (110)-rectangles, and 8 (111)-triangles, or (iii) 6 (100)-squares, 12 (110)-octagons, and 8 (100)-triangles. The analysis is valid for all compounds crystallizing in the cubic system and preferentially exposing the three enumerated faces.

  19. Phase diagram of elastic spheres.

    PubMed

    Athanasopoulou, L; Ziherl, P

    2017-02-15

    Experiments show that polymeric nanoparticles often self-assemble into several non-close-packed lattices in addition to the face-centered cubic lattice. Here, we explore theoretically the possibility that the observed phase sequences may be associated with the softness of the particles, which are modeled as elastic spheres interacting upon contact. The spheres are described by two finite-deformation theories of elasticity, the modified Saint-Venant-Kirchhoff model and the neo-Hookean model. We determine the range of indentations where the repulsion between the spheres is pairwise additive and agrees with the Hertz theory. By computing the elastic energies of nine trial crystal lattices at densities far beyond the Hertzian range, we construct the phase diagram and find the face- and body-centered cubic lattices as well as the A15 lattice and the simple hexagonal lattice, with the last two being stable at large densities where the spheres are completely faceted. These results are qualitatively consistent with observations, suggesting that deformability may indeed be viewed as a generic property that determines the phase behavior in nanocolloidal suspensions.

  20. Phase diagram of ammonium nitrate

    SciTech Connect

    Dunuwille, Mihindra; Yoo, Choong-Shik

    2013-12-07

    Ammonium Nitrate (AN) is a fertilizer, yet becomes an explosive upon a small addition of chemical impurities. The origin of enhanced chemical sensitivity in impure AN (or AN mixtures) is not well understood, posing significant safety issues in using AN even today. To remedy the situation, we have carried out an extensive study to investigate the phase stability of AN and its mixtures with hexane (ANFO–AN mixed with fuel oil) and Aluminum (Ammonal) at high pressures and temperatures, using diamond anvil cells (DAC) and micro-Raman spectroscopy. The results indicate that pure AN decomposes to N{sub 2}, N{sub 2}O, and H{sub 2}O at the onset of the melt, whereas the mixtures, ANFO and Ammonal, decompose at substantially lower temperatures. The present results also confirm the recently proposed phase IV-IV{sup ′} transition above 17 GPa and provide new constraints for the melting and phase diagram of AN to 40 GPa and 400°C.

  1. Phase Diagram of Ammonium Nitrate

    NASA Astrophysics Data System (ADS)

    Dunuwille, Mihindra; Yoo, Choong-Shik

    2013-06-01

    Ammonium Nitrate (AN) has often been subjected to uses in improvised explosive devices, due to its wide availability as a fertilizer and its capability of becoming explosive with slight additions of organic and inorganic compounds. Yet, the origin of enhanced energetic properties of impure AN (or AN mixtures) is neither chemically unique nor well understood - resulting in rather catastrophic disasters in the past1 and thereby a significant burden on safety, in using ammonium nitrates even today. To remedy this situation, we have carried out an extensive study to investigate the phase stability of AN, in different chemical environments, at high pressure and temperature, using diamond anvil cells and micro-Raman spectroscopy. The present results confirm the recently proposed phase IV-to-IV' transition above 15 GPa2 and provide new constraints for the melting and phase diagram of AN to 40 GPa and 673 K. The present study has been supported by the U.S. DHS under Award Number 2008-ST-061-ED0001.

  2. Predominance zone diagrams and their application to solvent extraction techniques.

    PubMed

    Páez-Hernández, M E; Ramírez, M T; Rojas-Hernández, A

    2000-01-24

    Predominance zone diagrams have been useful tools in solving problems in analytical chemistry. They can be used to establish the best conditions for separation of mixtures or to optimize recovery procedures for a given species. The few reports on predominance zone diagrams for the participant species in liquid-liquid extraction systems, describe their construction as diagrams of the Pourbaix type (epsilon/pH). With the generalized species and equilibria method (GSEM) it is possible to elaborate Predominance zone diagrams for extraction (PZDE) in proper spaces and with parameters strictly related to these processes such as pH and the volume ratio, r. Therefore, using the GSEM, PZDE that allow us to determine the best conditions for the extraction of a given substance have been elaborated. The stoichiometry of the species been extracted can also be determined from the experimental conditions. It has been demonstrated that with the GSEM, PZDE can be constructed for systems of one and two components. In this work, we intend to demonstrate that the algorithm is valid for the elaboration of PZDE in systems of three and four components. Examples of analytical interest are presented such as lead (II) extraction with diphenyltiocarbazone (dithizone) and that for cadmium (II) with 8-hydroxyquinolein (oxine) in chloroform. The influence of a masking agent, the etilendiaminotetraacetic acid (EDTA) over the extraction of both metals was also assessed.

  3. Economic impact assessment from the use of a mobile app for the self-management of heart diseases by patients with heart failure in a Spanish region.

    PubMed

    Cano Martín, José Antonio; Martínez-Pérez, Borja; de la Torre-Díez, Isabel; López-Coronado, Miguel

    2014-09-01

    Currently, cardiovascular diseases are the deadliest diseases with a total of 17 million deaths worldwide. Hence, they are the focus of many mobile applications for smartphones and tablets. This paper will assess the ex-ante economic impact as well as will determine the cost-effectiveness analysis that the use of one of this app, CardioManager, by patients with heart failure will have in a Spanish community, Castile and Leon. For this, a cost-effectiveness analysis using the hidden Markov model were performed in a hypothetical cohort of patients diagnosed with heart failure, based on the information of epidemiological parameters and the costs derived from the management and care of heart failure patients by the Public Health Care System of Castile and Leon. The costs of patient care were estimated from the perspective of the Ministry of Health of Spain using a discount rate of 3 %. Finally, an estimation of the ex-ante impact that would suppose the introduction of CardioManager in the Health Care System is performed. It is concluded that the introduction of CardioManager may generate a 33 % reduction in the cost of management and treatment of the disease. This means that CardioManager may be able to save more than 9,000 € per patient to the local Health Care System of Castile and Leon, which can be translated in a saving of 0.31 % of the total health expenditure of the region.

  4. No Such Thing as Failure, Only Feedback: Designing Innovative Opportunities for E-Assessment and Technology-Mediated Feedback

    ERIC Educational Resources Information Center

    Miller, Charles; Doering, Aaron; Scharber, Cassandra

    2010-01-01

    In this paper we challenge designers, researchers, teachers, students, and parents to re-assess and re-envision the value of technology-mediated feedback and e-assessment by examining the innovative roles feedback and assessment played in the design of three contemporary web-based learning environments. These environments include 1) an…

  5. Heart failure in pregnancy.

    PubMed

    Rutherford, John D

    2012-12-01

    With increasing maternal age and the presence of comorbid conditions such as hypertension, cardiovascular assessment and monitoring is the responsibility of all clinicians caring for pregnant patients. Furthermore, there are specific conditions, such as mitral stenosis, peripartum cardiomyopathy, and preeclampsia, that can be associated with heart failure and secondary maternal (and fetal) mortality and morbidity. The important causes of heart failure in pregnancy are discussed.

  6. Supervisory Control State Diagrams to Depict Autonomous Activity

    DTIC Science & Technology

    2013-06-01

    such as flowcharts, binary decision trees, goal graphs, finite state machine diagrams, and petri nets were assessed for their potential application...Horizons, 2010 p. 42). For future unmanned aerial vehicle (UAV) systems, the operator’s central responsibility conceivably shifts from teleoperation to...mission management and control for a team comprised of unmanned aerial vehicles (UAVs), unattended ground sensors (UGS), dismounted warfighters with

  7. [Using routine data for quality of care assessments: a critical review, taking quality indicators for the "National Disease Management Guideline for Chronic Heart Failure" as an example].

    PubMed

    Laux, Gunter; Nothacker, Monika; Weinbrenner, Susanne; Störk, Stefan; Blozik, Eva; Peters-Klimm, Frank; Szecsenyi, Jürgen; Scherer, Martin

    2011-01-01

    In December 2009, the first version of the German Disease Management Guideline (DM-CPG) for chronic heart failure was completed, including a set of proposed quality indicators for heart failure. This article explores whether proposed indicators can be derived from data collected routinely in general practices. For this purpose, previous experiences and data from the research project CONTENT (CONTinuous morbidity registration Epidemiologic NeTwork) conducted under guidance of the Department of General Medicine and Health Services Research at the University of Heidelberg, Germany, were applied. The availability of numerators and denominators needed for calculating the four quality indicators for diagnosis and pharmacotherapy proposed in the DM-CPG was checked within so-called "routine data" from the existing dataset of the CONTENT project. Within the given context, routine data are defined as data that are periodically transmitted from health care providers to cost units within the health care system. A thorough assessment has revealed that within the given context only one indicator could be deduced from routine data collection. This was the indicator measuring the proportion of patients receiving beta receptor antagonists, compared to all patients with heart failure NYHA class II to IV. Indeed, this single indicator will only be computable if the NYHA grade of heart failure severity and the presence or absence of contraindications to beta receptor antagonist therapy are routinely collected and the data merged into a central database. Against the background of these results it is obvious that a fully developed, transsectoral concept for data collection and data transfer needs to be implemented.

  8. Assessing the Quality and Comparative Effectiveness of Team-Based Care for Heart Failure: Who, What, Where, When, and How.

    PubMed

    Cooper, Lauren B; Hernandez, Adrian F

    2015-07-01

    Team-based or multidisciplinary care may be a potential way to positively impact outcomes for heart failure (HF) patients by improving clinical outcomes, managing patient symptoms, and reducing costs. The multidisciplinary team includes the HF cardiologist, HF nurses, clinical pharmacists, dieticians, exercise specialists, mental health providers, social workers, primary care providers, and additional subspecialty providers. The timing and setting of multidisciplinary care depends on the needs of the patient and the resources available. Multidisciplinary HF teams should be evaluated based on their ability to achieve goals, as well as their potential for sustainability over time.

  9. Assessment of nutritional status by composite index for anthropometric failure: a study among slum children in Bankura, West Bengal.

    PubMed

    Shit, Subhadeep; Taraphdar, Pranita; Mukhopadhyay, Dipta K; Sinhababu, Apurba; Biswas, Akhil B

    2012-01-01

    A community-based cross-sectional study was conducted to find out the prevalence of composite index of anthropometric failure (CIAF) among 117 slum dwelling under-five children in Bankura town, West Bengal and its relation with some common socio-economic factors. Among study population, the prevalence of underweight was 41.6%, whereas CIAF was 80.3%. CIAF gave a near complete estimation of undernutrition unlike underweight. Children who were unimmunized, with more number of siblings, living in a nuclear family, or with illiterate mothers were more likely to be undernourished.

  10. Phase diagrams of self-organizing maps

    NASA Astrophysics Data System (ADS)

    Bauer, H.-U.; Riesenhuber, M.; Geisel, T.

    1996-09-01

    We present a method which allows the analytic determination of phase diagrams in the self-organizing map, a model for the formation of topographic projection patterns in the brain and in signal processing applications. The method only requires an ansatz for the tesselation of the data space induced by the map, not for the explicit state of the map. We analytically obtain phase diagrams for various examples, including models for the development of orientation and ocular-dominance maps. The latter phase diagram exhibits transitions to broadening ocular-dominance patterns as observed in a recent experiment.

  11. Looking Forward, Looking Back: Assessing Variations in Hospital Resource Use and Outcomes for Elderly Patients with Heart Failure

    PubMed Central

    Ong, Michael K.; Mangione, Carol M.; Romano, Patrick S.; Zhou, Qiong; Auerbach, Andrew D.; Chun, Alein; Davidson, Bruce; Ganiats, Theodore G.; Greenfield, Sheldon; Gropper, Michael A.; Malik, Shaista; Rosenthal, J. Thomas; Escarce, José J.

    2009-01-01

    Background Recent studies have found substantial variation in hospital resource utilization by expired Medicare beneficiaries with chronic illnesses. By analyzing only expired patients, these studies cannot identify differences across hospitals in health outcomes like mortality. This study examines the association between mortality and resource utilization at the hospital level, when all Medicare beneficiaries hospitalized for heart failure are examined. Methods and Results 3,999 individuals hospitalized with a principal diagnosis of heart failure at six California teaching hospitals between January 1, 2001 and June 30, 2005 were analyzed with multivariate risk-adjustment models for total hospital days, total hospital direct costs, and mortality within 180-days after initial admission (“Looking Forward”). A subset of 1,639 individuals who died during the study period were analyzed with multivariate risk-adjustment models for total hospital days and total hospital direct costs within 180-days prior to death (“Looking Back”). “Looking Forward” risk-adjusted hospital means ranged from 17.0% to 26.0% for mortality, 7.8 to 14.9 days for total hospital days, and 0.66 to 1.30 times the mean value for indexed total direct costs. Spearman rank correlation coefficients were −0.68 between mortality and hospital days, and −0.93 between mortality and indexed total direct costs. “Looking Back” risk-adjusted hospital means ranged from 9.1 to 21.7 days for total hospital days and 0.91 to 1.79 times the mean value for indexed total direct costs. Variation in resource utilization site ranks between expired and all individuals were due to insignificant differences. Conclusions California teaching hospitals that used more resources caring for patients hospitalized for heart failure had lower mortality rates. Focusing only on expired individuals may overlook mortality variation as well as associations between greater resource utilization and lower mortality

  12. Assessment of Dyspnea Early in Acute Heart Failure: Patient Characteristics and Response Differences Between Likert and Visual Analog Scales

    PubMed Central

    Pang, Peter S.; Collins, Sean P.; Sauser, Kori; Andrei, Adin-Cristian; Storrow, Alan B.; Hollander, Judd E.; Tavares, Miguel; Spinar, Jindrich; Macarie, Cezar; Raev, Dimitar; Nowak, Richard; Gheorghiade, Mihai; Mebazaa, Alexandre

    2014-01-01

    Background Dyspnea is the most common symptom in acute heart failure (AHF), yet how to best measure it has not been well defined. Prior studies demonstrate differences in dyspnea improvement across various measurement scales, yet these studies typically enroll patients well after the ED phase of management. Objectives The aim of this study was to determine predictors of early dyspnea improvement for three different, commonly used dyspnea scales (i.e. five point absolute Likert scale, 10 cm visual analogue scale [VAS], or seven point relative Likert scale). Methods This was a post-hoc analysis of URGENT Dyspnea, an observational study of 776 patients in 17 countries enrolled within one hour of first physician encounter. Inclusion criteria were broad to reflect real-world clinical practice. Prior literature informed the a priori definition of clinically significant dyspnea improvement. Resampling-based multivariable models were created to determine patient characteristics significantly associated with dyspnea improvement. Results Of the 524 AHF patients, approximately 40% of patients did not report substantial dyspnea improvement within the first 6 hours. Baseline characteristics were similar between those who did or did not improve, though there were differences in history of heart failure, coronary artery disease, and initial systolic blood pressure. For those who did improve, patient characteristics differed across all three scales, with the exception of baseline dyspnea severity for the VAS and five point Likert scale (c-index ranged from 0.708 to 0.831 for each scale). Conclusions Predictors of early dyspnea improvement differ from scale to scale, with the exception of baseline dyspnea. Attempts to use one scale to capture the entirety of the dyspnea symptom may be insufficient. PMID:25039550

  13. [Heart failure and comorbidities].

    PubMed

    Boully, Clémence; Hanon, Olivier

    2015-03-01

    Heart failure is a frequent disease in the elderly. Its clinical presentation is less typical and the prognosis more severe than in younger subjects because heart failure occurs in patients with multiple comorbidities. A comprehensive geriatric assessment should therefore be performed to detect the vulnerabilities and manage the comorbidities. The main diseases associated with heart failure are dementia, depression, malnutrition, atrial fibrillation, coronary artery disease, orthostatic hypotension, renal failure, anemia and iron deficiency. Comorbidities worsen heart failure and makes its treatment more difficult. The identification and treatment of comorbidities improve the prognosis in terms of mortality but especially in terms of quality of life. Caution with drugs is necessary because of pharmacokinetic or pharmacodynamic changes related to aging and the comorbidities. In this context, clinical and laboratory monitoring should be increased, mostly during an acute event (acute heart failure, infection, dehydration, fall, new therapy…). Therefore, the follow-up of elderly patients with heart failure requires a multidisciplinary approach that involves close cooperation between cardiologists, geriatricians, general practitioners, nurses, and pharmacists.

  14. CADDIS Volume 5. Causal Databases: Interactive Conceptual Diagrams (ICDs)

    EPA Pesticide Factsheets

    In Interactive Conceptual Diagram (ICD) section of CADDIS allows users to create conceptual model diagrams, search a literature-based evidence database, and then attach that evidence to their diagrams.

  15. Veitch diagram plotter simplifies Boolean functions

    NASA Technical Reports Server (NTRS)

    Rubin, D. K.

    1964-01-01

    This device for simplifying the plotting of a Veitch diagram consists of several overlays for blocking out the unwanted squares. This method of plotting the various input combinations to a computer is used in conjunction with the Boolean functions.

  16. Some Geometric Aspects of the Ternary Diagram.

    ERIC Educational Resources Information Center

    Philip, G. M.; Watson, D. F.

    1989-01-01

    Uses the process of normalization in the Cartesian coordinate system which entails radial projection onto a transect to compare different compositions of minerals. Warns that the ternary diagram should not be used as a framework for calculations. (MVL)

  17. An Improved Mnemonic Diagram for Thermodynamic Relationships.

    ERIC Educational Resources Information Center

    Rodriguez, Joaquin; Brainard, Alan J.

    1989-01-01

    Considers pressure, volume, entropy, temperature, Helmholtz free energy, Gibbs free energy, enthalpy, and internal energy. Suggests the mnemonic diagram is for use with simple systems that are defined as macroscopically homogeneous, isotropic, uncharged, and chemically inert. (MVL)

  18. Lattice and Phase Diagram in QCD

    SciTech Connect

    Lombardo, Maria Paola

    2008-10-13

    Model calculations have produced a number of very interesting expectations for the QCD Phase Diagram, and the task of a lattice calculations is to put these studies on a quantitative grounds. I will give an overview of the current status of the lattice analysis of the QCD phase diagram, from the quantitative results of mature calculations at zero and small baryochemical potential, to the exploratory studies of the colder, denser phase.

  19. Elementary diagrams in nuclear and neutron matter

    SciTech Connect

    Wiringa, R.B.

    1995-08-01

    Variational calculations of nuclear and neutron matter are currently performed using a diagrammatic cluster expansion with the aid of nonlinear integral equations for evaluating expectation values. These are the Fermi hypernetted chain (FHNC) and single-operator chain (SOC) equations, which are a way of doing partial diagram summations to infinite order. A more complete summation can be made by adding elementary diagrams to the procedure. The simplest elementary diagrams appear at the four-body cluster level; there is one such E{sub 4} diagram in Bose systems, but 35 diagrams in Fermi systems, which gives a level of approximation called FHNC/4. We developed a novel technique for evaluating these diagrams, by computing and storing 6 three-point functions, S{sub xyz}(r{sub 12}, r{sub 13}, r{sub 23}), where xyz (= ccd, cce, ddd, dde, dee, or eee) denotes the exchange character at the vertices 1, 2, and 3. All 35 Fermi E{sub 4} diagrams can be constructed from these 6 functions and other two-point functions that are already calculated. The elementary diagrams are known to be important in some systems like liquid {sup 3}He. We expect them to be small in nuclear matter at normal density, but they might become significant at higher densities appropriate for neutron star calculations. This year we programmed the FHNC/4 contributions to the energy and tested them in a number of simple model cases, including liquid {sup 3}He and Bethe`s homework problem. We get reasonable, but not exact agreement with earlier published work. In nuclear and neutron matter with the Argonne v{sub 14} interaction these contributions are indeed small corrections at normal density and grow to only 5-10 MeV/nucleon at 5 times normal density.

  20. Kidney Failure

    MedlinePlus

    ... Dialysis or Transplant Paying for Kidney Failure Treatment Contact Us Health Information Center Phone: 1-800-860- ... to share this content freely. October 2, 2013 Contact Us Health Information Center Phone: 1-800-860- ...

  1. Heart Failure

    MedlinePlus

    ... for people who can't tolerate ACE inhibitors. Beta blockers. This class of drugs not only slows your ... rhythms and lessen your chance of dying unexpectedly. Beta blockers may reduce signs and symptoms of heart failure, ...

  2. Margins in high temperature leak-before-break assessments

    SciTech Connect

    Budden, P.J.; Hooton, D.G.

    1997-04-01

    Developments in the defect assessment procedure R6 to include high-temperature mechanisms in Leak-before-Break arguments are described. In particular, the effect of creep on the time available to detect a leak and on the crack opening area, and hence leak rate, is discussed. The competing influence of these two effects is emphasized by an example. The application to Leak-before-Break of the time-dependent failure assessment diagram approach for high temperature defect assessment is then outlined. The approach is shown to be of use in assessing the erosion of margins by creep.

  3. A pilot study to assess the feasibility of a submaximal exercise test to measure individual response to cardiac medication in dogs with acquired heart failure.

    PubMed

    Ferasin, L; Marcora, S

    2007-08-01

    Exercise testing is not commonly used in canine medicine because of several limitations. The aim of this study was to investigate the suitability of a treadmill test to measure the exercise capacity of untrained canine cardiac patients and to measure some biological parameters that might reflect the tolerance of dogs with heart failure to submaximal exercise. The exercise capacity of seven dogs with naturally occurring heart failure was evaluated before the institution of cardiac medication and 7 days after the beginning of the study. An additional re-examination was requested after 28 days. The exercise test was performed on a motorized treadmill at three different speeds (0.5 m/s, 1.0 m/s and 1.5 m/s). The following parameters were measured at the end of each stage and after 20 min recovery: heart rate, rectal temperature, glucose, lactate, aspartate aminotransferase, creatine kinase, PvO(2), PvCO(2), pH, haematocrit, bicarbonate, sodium, potassium and chloride. Serum cardiac troponin-I was also measured at the beginning of the test and at the end of the recovery period. Owners' perception reflected the ability of their dogs to exercise on the treadmill. Lactate level increased noticeably with the intensity of the exercise test, and its variation coincided with different exercise tolerance observed by the owners. Heart rate seemed to follow a similar trend in the few dogs presented in sinus rhythm. None of the remaining parameters appeared to be sensitive indicators of activity level in the dogs used in this study. The treadmill exercise test in dogs with acquired heart failure is feasible and might provide useful information for assessing individual response to cardiac medication. Lactate and heart rate seemed to reflect individual levels of exercise tolerance, although further studies are necessary to confirm the reliability and repeatability of this test.

  4. Heart failure

    PubMed Central

    2011-01-01

    Introduction Heart failure occurs in 3% to 4% of adults aged over 65 years, usually as a consequence of coronary artery disease or hypertension, and causes breathlessness, effort intolerance, fluid retention, and increased mortality. The 5-year mortality in people with systolic heart failure ranges from 25% to 75%, often owing to sudden death following ventricular arrhythmia. Risks of cardiovascular events are increased in people with left ventricular systolic dysfunction (LVSD) or heart failure. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of multidisciplinary interventions for heart failure? What are the effects of exercise in people with heart failure? What are the effects of drug treatments for heart failure? What are the effects of devices for treatment of heart failure? What are the effects of coronary revascularisation for treatment of heart failure? What are the effects of drug treatments in people at high risk of heart failure? What are the effects of treatments for diastolic heart failure? We searched: Medline, Embase, The Cochrane Library, and other important databases up to August 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 80 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: aldosterone receptor antagonists, amiodarone, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, anticoagulation, antiplatelet agents, beta-blockers, calcium

  5. Mechanical Design Support System Based on Thinking Process Development Diagram

    NASA Astrophysics Data System (ADS)

    Mase, Hisao; Kinukawa, Hiroshi; Morii, Hiroshi; Nakao, Masayuki; Hatamura, Yotaro

    This paper describes a system that directly supports a design process in a mechanical domain. This system is based on a thinking process development diagram that draws distinctions between requirement, tasks, solutions, and implementation, which enables designers to expand and deepen their thoughts of design. The system provides five main functions that designers require in each phase of the proposed design process: (1) thinking process description support which enables designers to describe their thoughts, (2) creativity support by term association with thesauri, (3) timely display of design knowledge including know-how obtained through earlier failures, general design theories, standard-parts data, and past designs, (4) design problem solving support using 46 kinds of thinking operations, and (5) proper technology transfer support which accumulates not only design conclusions but also the design process. Though this system is applied to mechanical engineering as the first target domain, it can be easily expanded to many other domains such as architecture and electricity.

  6. Learning from Failures.

    ERIC Educational Resources Information Center

    Saffran, Murray

    1991-01-01

    Describes mistakes made in trying to change the Nutrition and Digestion section of a medical biochemistry course. Author tried to make the section student taught and reports nine mistakes including the following: ignoring active opposition of colleagues, failure to assess the receptivity of the class to a new form of teaching, and overestimating…

  7. Application of ISO 22000 and Failure Mode and Effect Analysis (FMEA) for industrial processing of salmon: a case study.

    PubMed

    Arvanitoyannis, Ioannis S; Varzakas, Theodoros H

    2008-05-01

    The Failure Mode and Effect Analysis (FMEA) model was applied for risk assessment of salmon manufacturing. A tentative approach of FMEA application to the salmon industry was attempted in conjunction with ISO 22000. Preliminary Hazard Analysis was used to analyze and predict the occurring failure modes in a food chain system (salmon processing plant), based on the functions, characteristics, and/or interactions of the ingredients or the processes, upon which the system depends. Critical Control points were identified and implemented in the cause and effect diagram (also known as Ishikawa, tree diagram and fishbone diagram). In this work, a comparison of ISO 22000 analysis with HACCP is carried out over salmon processing and packaging. However, the main emphasis was put on the quantification of risk assessment by determining the RPN per identified processing hazard. Fish receiving, casing/marking, blood removal, evisceration, filet-making cooling/freezing, and distribution were the processes identified as the ones with the highest RPN (252, 240, 210, 210, 210, 210, 200 respectively) and corrective actions were undertaken. After the application of corrective actions, a second calculation of RPN values was carried out resulting in substantially lower values (below the upper acceptable limit of 130). It is noteworthy that the application of Ishikawa (Cause and Effect or Tree diagram) led to converging results thus corroborating the validity of conclusions derived from risk assessment and FMEA. Therefore, the incorporation of FMEA analysis within the ISO 22000 system of a salmon processing industry is anticipated to prove advantageous to industrialists, state food inspectors, and consumers.

  8. Premature ovarian failure.

    PubMed

    Kalantaridou, S N; Davis, S R; Nelson, L M

    1998-12-01

    In 1% of women, premature ovarian failure develops by 40 years of age, a condition causing amenorrhea, infertility, sex steroid deficiency, and elevated gonadotropins. Early loss of ovarian function has significant psychosocial sequelae and major health implications. These young women have a nearly two-fold age-specific increase in mortality rate. Among women with spontaneous premature ovarian failure who have a normal karyotype, half have ovarian follicles remaining in the ovary that function intermittently. Indeed, pregnancies have occurred after the diagnosis of premature ovarian failure. Thus, premature ovarian failure should not be considered as a premature menopause. Young women with this disorder have a 5% to 10% chance for spontaneous pregnancy. Attempts at ovulation induction using various regimens fail to induce ovulation rates greater than those seen in untreated patients; however, oocyte donation for women desiring fertility is an option. Young women with premature ovarian failure need a thorough assessment, sex steroid replacement, and long-term surveillance to monitor therapy. Estrogen-progestin replacement therapy should be instituted as soon as the diagnosis is made. Androgen replacement should also be considered for women with low libido, persistent fatigue, and poor well-being despite taking adequate estrogen replacement. Women with premature ovarian failure should be followed up for the presence of associated autoimmune endocrine disorders such as hypothyroidism, adrenal insufficiency, and diabetes mellitus.

  9. TIME-TEMPERATURE-TRANSFORMATION (TTT) DIAGRAMS FOR FUTURE WASTE COMPOSITIONS

    SciTech Connect

    Billings, A.; Edwards, T.

    2010-07-08

    As a part of the Waste Acceptance Product Specifications (WAPS) for Vitrified High-Level Waste Forms defined by the Department of Energy - Office of Environmental Management, the waste form stability must be determined for each of the projected high-level waste (HLW) types at the Savannah River Site (SRS). Specifically, WAPS 1.4.1 requires the glass transition temperature (T{sub g}) to be defined and time-temperature-transformation (TTT) diagrams to be developed. The T{sub g} of a glass is an indicator of the approximate temperature where the supercooled liquid converts to a solid on cooling or conversely, where the solid begins to behave as a viscoelastic solid on heating. A TTT diagram identifies the crystalline phases that can form as a function of time and temperature for a given waste type or more specifically, the borosilicate glass waste form. In order to assess durability, the Product Consistency Test (PCT) was used and the durability results compared to the Environmental Assessment (EA) glass. The measurement of glass transition temperature and the development of TTT diagrams have already been performed for the seven Defense Waste Processing Facility (DWPF) projected compositions as defined in the Waste Form Compliance Plan (WCP) and in SRNL-STI-2009-00025. Additional phase transformation information exists for other projected compositions, but overall these compositions did not cover composition regions estimated for future waste processing. To develop TTT diagrams for future waste types, the Savannah River National Laboratory (SRNL) fabricated two caches of glass from reagent grade oxides to simulate glass compositions which would be likely processed with and without Al dissolution. These were used for glass transition temperature measurement and TTT diagram development. The glass transition temperatures of both glasses were measured using differential scanning calorimetry (DSC) and were recorded to be 448 C and 452 C. Using the previous TTT diagrams as

  10. Introduction to causal diagrams for confounder selection.

    PubMed

    Williamson, Elizabeth J; Aitken, Zoe; Lawrie, Jock; Dharmage, Shyamali C; Burgess, John A; Forbes, Andrew B

    2014-04-01

    In respiratory health research, interest often lies in estimating the effect of an exposure on a health outcome. If randomization of the exposure of interest is not possible, estimating its effect is typically complicated by confounding bias. This can often be dealt with by controlling for the variables causing the confounding, if measured, in the statistical analysis. Common statistical methods used to achieve this include multivariable regression models adjusting for selected confounding variables or stratification on those variables. Therefore, a key question is which measured variables need to be controlled for in order to remove confounding. An approach to confounder-selection based on the use of causal diagrams (often called directed acyclic graphs) is discussed. A causal diagram is a visual representation of the causal relationships believed to exist between the variables of interest, including the exposure, outcome and potential confounding variables. After creating a causal diagram for the research question, an intuitive and easy-to-use set of rules can be applied, based on a foundation of rigorous mathematics, to decide which measured variables must be controlled for in the statistical analysis in order to remove confounding, to the extent that is possible using the available data. This approach is illustrated by constructing a causal diagram for the research question: 'Does personal smoking affect the risk of subsequent asthma?'. Using data taken from the Tasmanian Longitudinal Health Study, the statistical analysis suggested by the causal diagram approach was performed.

  11. Dynamic tactile diagram simplification on refreshable displays.

    PubMed

    Rastogi, Ravi; Pawluk, Dianne T V

    2013-01-01

    The increasing use of visual diagrams in educational and work environments, and even our daily lives, has created obstacles for individuals who are blind or visually impaired to independently access the information they represent. Although physical tactile pictures can be created to convey the visual information, it is typically a slow, cumbersome, and costly process. Refreshable haptic displays, which interact with computers, promise to make this access quicker, easier, and cheaper. One important aspect in converting visual to tactile diagrams is to simplify the diagram as otherwise it can be too difficult to interpret with touch. Enabling this to be under user control in an interactive environment, such as with refreshable displays, could allow users to avoid being overwhelmed by the diagrams at any instant in time while still retaining access to all information in "storage". Through this article the authors investigate whether two types of diagram simplification--boundary simplification and contextual simplification--showed potential utility in an interactive environment. Boundary simplification was found to be significantly helpful in answering general questions about borders on a geographic map, and contextual simplification was helpful in answering relational questions, as compared to using the original map unchanged.

  12. Heart failure

    PubMed Central

    2010-01-01

    Introduction Heart failure occurs in 3% to 4% of adults aged over 65 years, usually as a consequence of coronary artery disease or hypertension, and causes breathlessness, effort intolerance, fluid retention, and increased mortality. The 5-year mortality in people with systolic heart failure ranges from 25% to 75%, often owing to sudden death following ventricular arrhythmia. Risks of cardiovascular events are increased in people with left ventricular systolic dysfunction (LVSD) or heart failure. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of non-drug treatments, and of drug and invasive treatments, for heart failure? What are the effects of angiotensin-converting enzyme inhibitors in people at high risk of heart failure? What are the effects of treatments for diastolic heart failure? We searched: Medline, Embase, The Cochrane Library, and other important databases up to May 2009 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 85 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: aldosterone receptor antagonists, amiodarone, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, anticoagulation, antiplatelet agents, beta-blockers, calcium channel blockers, cardiac resynchronisation therapy, digoxin (in people already receiving diuretics and angiotensin-converting enzyme inhibitors), exercise, hydralazine plus isosorbide dinitrate, implantable cardiac

  13. The Semiotic Structure of Geometry Diagrams: How Textbook Diagrams Convey Meaning

    ERIC Educational Resources Information Center

    Dimmel, Justin K.; Herbst, Patricio G.

    2015-01-01

    Geometry diagrams use the visual features of specific drawn objects to convey meaning about generic mathematical entities. We examine the semiotic structure of these visual features in two parts. One, we conduct a semiotic inquiry to conceptualize geometry diagrams as mathematical texts that comprise choices from different semiotic systems. Two,…

  14. 49 CFR 1152.10 - System diagram map.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 8 2013-10-01 2013-10-01 false System diagram map. 1152.10 Section 1152.10... TRANSPORTATION UNDER 49 U.S.C. 10903 System Diagram § 1152.10 System diagram map. (a) Each carrier shall prepare a diagram of its rail system on a map, designating all lines in its system by the...

  15. 49 CFR 1152.10 - System diagram map.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 8 2012-10-01 2012-10-01 false System diagram map. 1152.10 Section 1152.10... TRANSPORTATION UNDER 49 U.S.C. 10903 System Diagram § 1152.10 System diagram map. (a) Each carrier shall prepare a diagram of its rail system on a map, designating all lines in its system by the...

  16. Fishbone Diagrams: Organize Reading Content with a "Bare Bones" Strategy

    ERIC Educational Resources Information Center

    Clary, Renee; Wandersee, James

    2010-01-01

    Fishbone diagrams, also known as Ishikawa diagrams or cause-and-effect diagrams, are one of the many problem-solving tools created by Dr. Kaoru Ishikawa, a University of Tokyo professor. Part of the brilliance of Ishikawa's idea resides in the simplicity and practicality of the diagram's basic model--a fish's skeleton. This article describes how…

  17. Use of Affinity Diagrams as Instructional Tools in Inclusive Classrooms.

    ERIC Educational Resources Information Center

    Haselden, Polly G.

    2003-01-01

    This article describes how the affinity diagram, a tool for gathering information and organizing it into natural groupings, can be used in inclusive classrooms. It discusses how students can be taught to use an affinity diagram, how affinity diagrams can be used to reflect many voices, and how affinity diagrams can be used to plan class projects.…

  18. The Butterfly diagram leopard skin pattern

    NASA Astrophysics Data System (ADS)

    Ternullo, Maurizio

    2011-08-01

    A time-latitude diagram where spotgroups are given proportional relevance to their area is presented. The diagram reveals that the spotted area distribution is higly dishomogeneous, most of it being concentrated in few, small portions (``knots'') of the Butterfly Diagram; because of this structure, the BD may be properly described as a cluster of knots. The description, assuming that spots scatter around the ``spot mean latitude'' steadily drifting equatorward, is challenged. Indeed, spots cluster around at as many latitudes as knots; a knot may appear at either lower or higher latitudes than previous ones, in a seemingly random way; accordingly, the spot mean latitude abruptly drifts equatorward or even poleward at any knot activation, in spite of any smoothing procedure. Preliminary analyses suggest that the activity splits, in any hemisphere, into two or more distinct ``activity waves'', drifting equatorward at a rate higher than the spot zone as a whole.

  19. Kidney (Renal) Failure

    MedlinePlus

    ... News Physician Resources Professions Site Index A-Z Kidney Failure Kidney failure, also known as renal failure, ... evaluated? How is kidney failure treated? What is kidney (renal) failure? The kidneys are designed to maintain ...

  20. Low-Probability High-Consequence (LPHC) Failure Events in Geologic Carbon Sequestration Pipelines and Wells: Framework for LPHC Risk Assessment Incorporating Spatial Variability of Risk

    SciTech Connect

    Oldenburg, Curtis M.; Budnitz, Robert J.

    2016-08-31

    If Carbon dioxide Capture and Storage (CCS) is to be effective in mitigating climate change, it will need to be carried out on a very large scale. This will involve many thousands of miles of dedicated high-pressure pipelines in order to transport many millions of tonnes of CO2 annually, with the CO2 delivered to many thousands of wells that will inject the CO2 underground. The new CCS infrastructure could rival in size the current U.S. upstream natural gas pipeline and well infrastructure. This new infrastructure entails hazards for life, health, animals, the environment, and natural resources. Pipelines are known to rupture due to corrosion, from external forces such as impacts by vehicles or digging equipment, by defects in construction, or from the failure of valves and seals. Similarly, wells are vulnerable to catastrophic failure due to corrosion, cement degradation, or operational mistakes. While most accidents involving pipelines and wells will be minor, there is the inevitable possibility of accidents with very high consequences, especially to public health. The most important consequence of concern is CO2 release to the environment in concentrations sufficient to cause death by asphyxiation to nearby populations. Such accidents are thought to be very unlikely, but of course they cannot be excluded, even if major engineering effort is devoted (as it will be) to keeping their probability low and their consequences minimized. This project has developed a methodology for analyzing the risks of these rare but high-consequence accidents, using a step-by-step probabilistic methodology. A key difference between risks for pipelines and wells is that the former are spatially distributed along the pipe whereas the latter are confined to the vicinity of the well. Otherwise, the methodology we develop for risk assessment of pipeline and well failures is similar and provides an analysis both of the annual probabilities of

  1. Clinical usefulness of blood metal measurements to assess the failure of metal-on-metal hip implants

    PubMed Central

    Sampson, Barry; Hart, Alister

    2012-01-01

    In April 2010, a Medicines and Healthcare Products Regulatory Agency safety alert concerning all metal-on-metal (MOM) hip replacements recommended measuring chromium and cobalt concentrations when managing patients with painful prostheses. The need for this review is illustrated by the recent surge in requests for these blood tests from orthopaedic surgeons following this alert. The aim is to provide guidance to laboratories in assessing these requests and advising clinicians on interpretation. First, we summarize the basic terminology regarding the types of hip replacements, with emphasis on the MOM type. Second, we describe the clinical concerns over implant-derived wear debris in the local tissues and distant sites. Analytical aspects of the measurement of the relevant metal ions and what factors affect the levels measured are discussed. The application of inductively coupled plasma mass spectrometry techniques to the measurement of these metals is considered in detail. The biological effects of metal wear products are summarized with local toxicity and systemic biological effects considered, including carcinogenicity, genotoxicity and systemic toxicity. Clinical cases are used to illustrate pertinent points. PMID:22155921

  2. Common Cause Failure Modeling

    NASA Technical Reports Server (NTRS)

    Hark, Frank; Britton, Paul; Ring, Rob; Novack, Steven D.

    2015-01-01

    Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFS are a set of dependent type of failures that can be caused by: system environments; manufacturing; transportation; storage; maintenance; and assembly, as examples. Since there are many factors that contribute to CCFs, the effects can be reduced, but they are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and CCF (dependent) failure and data is limited, especially for launch vehicles. The Probabilistic Risk Assessment (PRA) of NASA's Safety and Mission Assurance Directorate at Marshall Space Flight Center (MFSC) is using generic data from the Nuclear Regulatory Commission's database of common cause failures at nuclear power plants to estimate CCF due to the lack of a more appropriate data source. There remains uncertainty in the actual magnitude of the common cause risk estimates for different systems at this stage of the design. Given the limited data about launch vehicle CCF and that launch vehicles are a highly redundant system by design, it is important to make design decisions to account for a range of values for independent and CCFs. When investigating the design of the one-out-of-two component redundant system for launch vehicles, a response surface was constructed to represent the impact of the independent failure rate versus a common cause beta factor effect on a system's failure probability. This presentation will define a CCF and review estimation calculations. It gives a summary of reduction methodologies and a review of examples of historical CCFs. Finally, it presents the response surface and discusses the results of the different CCFs on the reliability of a one-out-of-two system.

  3. Common Cause Failure Modeling

    NASA Technical Reports Server (NTRS)

    Hark, Frank; Britton, Paul; Ring, Rob; Novack, Steven D.

    2016-01-01

    Common Cause Failures (CCFs) are a known and documented phenomenon that defeats system redundancy. CCFS are a set of dependent type of failures that can be caused by: system environments; manufacturing; transportation; storage; maintenance; and assembly, as examples. Since there are many factors that contribute to CCFs, the effects can be reduced, but they are difficult to eliminate entirely. Furthermore, failure databases sometimes fail to differentiate between independent and CCF (dependent) failure and data is limited, especially for launch vehicles. The Probabilistic Risk Assessment (PRA) of NASA's Safety and Mission Assurance Directorate at Marshal Space Flight Center (MFSC) is using generic data from the Nuclear Regulatory Commission's database of common cause failures at nuclear power plants to estimate CCF due to the lack of a more appropriate data source. There remains uncertainty in the actual magnitude of the common cause risk estimates for different systems at this stage of the design. Given the limited data about launch vehicle CCF and that launch vehicles are a highly redundant system by design, it is important to make design decisions to account for a range of values for independent and CCFs. When investigating the design of the one-out-of-two component redundant system for launch vehicles, a response surface was constructed to represent the impact of the independent failure rate versus a common cause beta factor effect on a system's failure probability. This presentation will define a CCF and review estimation calculations. It gives a summary of reduction methodologies and a review of examples of historical CCFs. Finally, it presents the response surface and discusses the results of the different CCFs on the reliability of a one-out-of-two system.

  4. Visualization of geologic stress perturbations using Mohr diagrams.

    PubMed

    Crossno, Patricia; Rogers, David H; Brannon, Rebecca M; Coblentz, David; Fredrich, Joanne T

    2005-01-01

    Huge salt formations, trapping large untapped oil and gas reservoirs, lie in the deepwater region of the Gulf of Mexico. Drilling in this region is high-risk and drilling failures have led to well abandonments, with each costing tens of millions of dollars. Salt tectonics plays a central role in these failures. To explore the geomechanical interactions between salt and the surrounding sand and shale formations, scientists have simulated the stresses in and around salt diapirs in the Gulf of Mexico using nonlinear finite element geomechanical modeling. In this paper, we describe novel techniques developed to visualize the simulated subsurface stress field. We present an adaptation of the Mohr diagram, a traditional paper-and-pencil graphical method long used by the material mechanics community for estimating coordinate transformations for stress tensors, as a new tensor glyph for dynamically exploring tensor variables within three-dimensional finite element models. This interactive glyph can be used as either a probe or a filter through brushing and linking.

  5. Weight diagram construction of Lax operators

    SciTech Connect

    Carbon, S.L.; Piard, E.J.

    1991-10-01

    We review and expand methods introduced in our previous paper. It is proved that cyclic weight diagrams corresponding to representations of affine Lie algebras allow one to construct the associated Lax operator. The resultant Lax operator is in the Miura-like form and generates the modified KdV equations. The algorithm is extended to the super-symmetric case.

  6. Valid Structure Diagrams and Chemical Gibberish

    ERIC Educational Resources Information Center

    Tauber, Stephen J.; Rankin, Kirk

    1972-01-01

    Chemical structure diagrams are considered as utterances in a written language. Two types of grammars are considered for this language: topological grammars and geometric grammars. The hypothesis is presented that compact computer storage may become accessible via grammars. (15 references) (Author/NH)

  7. Image Attributes: A Study of Scientific Diagrams.

    ERIC Educational Resources Information Center

    Brunskill, Jeff; Jorgensen, Corinne

    2002-01-01

    Discusses advancements in imaging technology and increased user access to digital images, as well as efforts to develop adequate indexing and retrieval methods for image databases. Describes preliminary results of a study of undergraduates that explored the attributes naive subjects use to describe scientific diagrams. (Author/LRW)

  8. The Binary Temperature-Composition Phase Diagram

    ERIC Educational Resources Information Center

    Sanders, Philip C.; Reeves, James H.; Messina, Michael

    2006-01-01

    The equations for the liquid and gas lines in the binary temperature-composition phase diagram are derived by approximating that delta(H)[subscript vap] of the two liquids are equal. It is shown that within this approximation, the resulting equations are not too difficult to present in an undergraduate physical chemistry lecture.

  9. The Keynesian Diagram: A Cross to Bear?

    ERIC Educational Resources Information Center

    Fleck, Juergen

    In elementary economics courses students are often introduced to the basic concepts of macroeconomics through very simplified static models, and the concept of a macroeconomic equilibrium is generally explained with the help of an aggregate demand/aggregate supply (AD/AS) model and an income/expenditure model (via the Keynesian cross diagram).…

  10. Computer-Generated Diagrams for the Classroom.

    ERIC Educational Resources Information Center

    Carle, Mark A.; Greenslade, Thomas B., Jr.

    1986-01-01

    Describes 10 computer programs used to draw diagrams usually drawn on chalkboards, such as addition of three vectors, vector components, range of a projectile, lissajous figures, beats, isotherms, Snell's law, waves passing through a lens, magnetic field due to Helmholtz coils, and three curves. Several programming tips are included. (JN)

  11. Data Exploration: Transposition Operations in Dynamic Diagrams.

    ERIC Educational Resources Information Center

    Sivasankaran, Vijay K.; Owen, Charles L.

    1992-01-01

    Defines transposition operations (changing the way the display of the model proceeds) in diagrams within computer graphics. Describes transpositions that are spatial (moving the point of view or the point viewed), procedural (changing the flow of time), or organizational (arranging multiple simultaneous views and interjecting auxiliary measuring…

  12. Drawing conformal diagrams for a fractal landscape

    SciTech Connect

    Winitzki, Sergei

    2005-06-15

    Generic models of cosmological inflation and the recently proposed scenarios of a recycling universe and the string theory landscape predict spacetimes whose global geometry is a stochastic, self-similar fractal. To visualize the complicated causal structure of such a universe, one usually draws a conformal (Carter-Penrose) diagram. I develop a new method for drawing conformal diagrams, applicable to arbitrary 1+1-dimensional spacetimes. This method is based on a qualitative analysis of intersecting lightrays and thus avoids the need for explicit transformations of the spacetime metric. To demonstrate the power and simplicity of this method, I present derivations of diagrams for spacetimes of varying complication. I then apply the lightray method to three different models of an eternally inflating universe (scalar-field inflation, recycling universe, and string theory landscape) involving the nucleation of nested asymptotically flat, de Sitter and/or anti-de Sitter bubbles. I show that the resulting diagrams contain a characteristic fractal arrangement of lines.

  13. Fog Machines, Vapors, and Phase Diagrams

    ERIC Educational Resources Information Center

    Vitz, Ed

    2008-01-01

    A series of demonstrations is described that elucidate the operation of commercial fog machines by using common laboratory equipment and supplies. The formation of fogs, or "mixing clouds", is discussed in terms of the phase diagram for water and other chemical principles. The demonstrations can be adapted for presentation suitable for elementary…

  14. Dynamic Tactile Diagram Simplification on Refreshable Displays

    ERIC Educational Resources Information Center

    Rastogi, Ravi; Pawluk, Dianne T. V.

    2013-01-01

    The increasing use of visual diagrams in educational and work environments, and even our daily lives, has created obstacles for individuals who are blind or visually impaired to "independently" access the information they represent. Although physical tactile pictures can be created to convey the visual information, it is typically a slow,…

  15. Geometrical splitting and reduction of Feynman diagrams

    NASA Astrophysics Data System (ADS)

    Davydychev, Andrei I.

    2016-10-01

    A geometrical approach to the calculation of N-point Feynman diagrams is reviewed. It is shown that the geometrical splitting yields useful connections between Feynman integrals with different momenta and masses. It is demonstrated how these results can be used to reduce the number of variables in the occurring functions.

  16. Complexities of One-Component Phase Diagrams

    ERIC Educational Resources Information Center

    Ciccioli, Andrea; Glasser, Leslie

    2011-01-01

    For most materials, the solid at and near the triple-point temperature is denser than the liquid with which it is in equilibrium. However, for water and certain other materials, the densities of the phases are reversed, with the solid being less dense. The profound consequences for the appearance of the "pVT" diagram of one-component materials…

  17. Phase diagram of spiking neural networks

    PubMed Central

    Seyed-allaei, Hamed

    2015-01-01

    In computer simulations of spiking neural networks, often it is assumed that every two neurons of the network are connected by a probability of 2%, 20% of neurons are inhibitory and 80% are excitatory. These common values are based on experiments, observations, and trials and errors, but here, I take a different perspective, inspired by evolution, I systematically simulate many networks, each with a different set of parameters, and then I try to figure out what makes the common values desirable. I stimulate networks with pulses and then measure their: dynamic range, dominant frequency of population activities, total duration of activities, maximum rate of population and the occurrence time of maximum rate. The results are organized in phase diagram. This phase diagram gives an insight into the space of parameters – excitatory to inhibitory ratio, sparseness of connections and synaptic weights. This phase diagram can be used to decide the parameters of a model. The phase diagrams show that networks which are configured according to the common values, have a good dynamic range in response to an impulse and their dynamic range is robust in respect to synaptic weights, and for some synaptic weights they oscillates in α or β frequencies, independent of external stimuli. PMID:25788885

  18. On phase diagrams of magnetic reconnection

    SciTech Connect

    Cassak, P. A.; Drake, J. F.

    2013-06-15

    Recently, “phase diagrams” of magnetic reconnection were developed to graphically organize the present knowledge of what type, or phase, of reconnection is dominant in systems with given characteristic plasma parameters. Here, a number of considerations that require caution in using the diagrams are pointed out. First, two known properties of reconnection are omitted from the diagrams: the history dependence of reconnection and the absence of reconnection for small Lundquist number. Second, the phase diagrams mask a number of features. For one, the predicted transition to Hall reconnection should be thought of as an upper bound on the Lundquist number, and it may happen for considerably smaller values. Second, reconnection is never “slow,” it is always “fast” in the sense that the normalized reconnection rate is always at least 0.01. This has important implications for reconnection onset models. Finally, the definition of the relevant Lundquist number is nuanced and may differ greatly from the value based on characteristic scales. These considerations are important for applications of the phase diagrams. This is demonstrated by example for solar flares, where it is argued that it is unlikely that collisional reconnection can occur in the corona.

  19. Identifying Conservation Successes, Failures and Future Opportunities; Assessing Recovery Potential of Wild Ungulates and Tigers in Eastern Cambodia

    PubMed Central

    O'Kelly, Hannah J.; Evans, Tom D.; Stokes, Emma J.; Clements, Tom J.; Dara, An; Gately, Mark; Menghor, Nut; Pollard, Edward H. B.; Soriyun, Men; Walston, Joe

    2012-01-01

    Conservation investment, particularly for charismatic and wide-ranging large mammal species, needs to be evidence-based. Despite the prevalence of this theme within the literature, examples of robust data being generated to guide conservation policy and funding decisions are rare. We present the first published case-study of tiger conservation in Indochina, from a site where an evidence-based approach has been implemented for this iconic predator and its prey. Despite the persistence of extensive areas of habitat, Indochina's tiger and ungulate prey populations are widely supposed to have precipitously declined in recent decades. The Seima Protection Forest (SPF), and broader Eastern Plains Landscape, was identified in 2000 as representing Cambodia's best hope for tiger recovery; reflected in its designation as a Global Priority Tiger Conservation Landscape. Since 2005 distance sampling, camera-trapping and detection-dog surveys have been employed to assess the recovery potential of ungulate and tiger populations in SPF. Our results show that while conservation efforts have ensured that small but regionally significant populations of larger ungulates persist, and density trends in smaller ungulates are stable, overall ungulate populations remain well below theoretical carrying capacity. Extensive field surveys failed to yield any evidence of tiger, and we contend that there is no longer a resident population within the SPF. This local extirpation is believed to be primarily attributable to two decades of intensive hunting; but importantly, prey densities are also currently below the level necessary to support a viable tiger population. Based on these results and similar findings from neighbouring sites, Eastern Cambodia does not currently constitute a Tiger Source Site nor meet the criteria of a Global Priority Tiger Landscape. However, SPF retains global importance for many other elements of biodiversity. It retains high regional importance for ungulate

  20. Identifying conservation successes, failures and future opportunities; assessing recovery potential of wild ungulates and tigers in Eastern Cambodia.

    PubMed

    O'Kelly, Hannah J; Evans, Tom D; Stokes, Emma J; Clements, Tom J; Dara, An; Gately, Mark; Menghor, Nut; Pollard, Edward H B; Soriyun, Men; Walston, Joe

    2012-01-01

    Conservation investment, particularly for charismatic and wide-ranging large mammal species, needs to be evidence-based. Despite the prevalence of this theme within the literature, examples of robust data being generated to guide conservation policy and funding decisions are rare. We present the first published case-study of tiger conservation in Indochina, from a site where an evidence-based approach has been implemented for this iconic predator and its prey. Despite the persistence of extensive areas of habitat, Indochina's tiger and ungulate prey populations are widely supposed to have precipitously declined in recent decades. The Seima Protection Forest (SPF), and broader Eastern Plains Landscape, was identified in 2000 as representing Cambodia's best hope for tiger recovery; reflected in its designation as a Global Priority Tiger Conservation Landscape. Since 2005 distance sampling, camera-trapping and detection-dog surveys have been employed to assess the recovery potential of ungulate and tiger populations in SPF. Our results show that while conservation efforts have ensured that small but regionally significant populations of larger ungulates persist, and density trends in smaller ungulates are stable, overall ungulate populations remain well below theoretical carrying capacity. Extensive field surveys failed to yield any evidence of tiger, and we contend that there is no longer a resident population within the SPF. This local extirpation is believed to be primarily attributable to two decades of intensive hunting; but importantly, prey densities are also currently below the level necessary to support a viable tiger population. Based on these results and similar findings from neighbouring sites, Eastern Cambodia does not currently constitute a Tiger Source Site nor meet the criteria of a Global Priority Tiger Landscape. However, SPF retains global importance for many other elements of biodiversity. It retains high regional importance for ungulate

  1. The role of post-failure brittleness of soft rocks in the assessment of stability of intact masses: FDEM technique applications to ideal problems

    NASA Astrophysics Data System (ADS)

    Lollino, Piernicola; Andriani, Gioacchino Francesco; Fazio, Nunzio Luciano; Perrotti, Michele

    2016-04-01

    Strain-softening under low confinement stress, i.e. the drop of strength that occurs in the post-failure stage, represents a key factor of the stress-strain behavior of rocks. However, this feature of the rock behavior is generally underestimated or even neglected in the assessment of boundary value problems of intact soft rock masses. This is typically the case when the stability of intact rock masses is treated by means of limit equilibrium or finite element analyses, for which rigid-plastic or elastic perfectly-plastic constitutive models, generally implementing peak strength conditions of the rock, are respectively used. In fact, the aforementioned numerical techniques are characterized by intrinsic limitations that do not allow to account for material brittleness, either for the method assumptions or due to numerical stability problems, as for the case of the finite element method, unless sophisticated regularization techniques are implemented. However, for those problems that concern the stability of intact soft rock masses at low stress levels, as for example the stability of shallow underground caves or that of rock slopes, the brittle stress-strain response of rock in the post-failure stage cannot be disregarded due to the risk of overestimation of the stability factor. This work is aimed at highlighting the role of post-peak brittleness of soft rocks in the analysis of specific ideal problems by means of the use of a hybrid finite-discrete element technique (FDEM) that allows for the simulation of the rock stress-strain brittle behavior in a proper way. In particular, the stability of two ideal cases, represented by a shallow underground rectangular cave and a vertical cliff, has been analyzed by implementing a post-peak brittle behavior of the rock and the comparison with a non-brittle response of the rock mass is also explored. To this purpose, the mechanical behavior of a soft calcarenite belonging to the Calcarenite di Gravina formation, extensively

  2. Prospective Assessment of Patterns of Failure After High-Precision Definitive (Chemo)Radiation in Head-and-Neck Squamous Cell Carcinoma

    SciTech Connect

    Gupta, Tejpal

    2011-06-01

    Purpose: To prospectively analyze patterns of failure in patients with head-and-neck squamous cell carcinoma treated with definitive high-precision radiotherapy with a focus on location of failure relative to target volume coverage. Methods and Materials: Sixty patients treated with three-dimensional conformal radiotherapy or intensity-modulated radiation therapy were included. Locoregional failure volume was defined on the planning data set at relapse, and dose received was analyzed by use of dose-volume histograms. Results: Thirteen patients were deemed to have had locoregional failures, of which two did not have any viable tumor on salvage neck dissection, leaving eleven patients with proven persistent or recurrent locoregional disease. Of these, 9 patients had in-field failure, 1 marginal failure, and 1 both in-field and marginal failures. Overall, only 2 of 11 patients (18%) with relapse had any marginal failure. Of the 20 sites of locoregional failure, 15 (75%) were in-field and 5 (25%) marginal. Distant metastases were detected in 3 patients, whereas a second new primary developed in 3 others. With a median follow-up of 26 months (interquartile range, 18-31 months) for surviving patients, the 3-year local control, locoregional control, disease-free survival, and overall survival rates were 75.3%, 74%, 67.2%, and 60.5%, respectively. Conclusions: Locoregional relapse remains the predominant pattern of failure in head-and-neck squamous cell carcinoma treated with high-precision definitive radiotherapy with the majority of failures occurring 'in-field' within the high-dose volume. Marginal failures can occur, particularly in the vicinity of the spared parotid gland. The therapeutic index of high-precision conformal radiotherapy is largely dependent on adequate selection and delineation of target volumes and organs at risk.

  3. New web-based applications for mechanistic case diagramming.

    PubMed

    Dee, Fred R; Haugen, Thomas H; Kreiter, Clarence D

    2014-01-01

    The goal of mechanistic case diagraming (MCD) is to provide students with more in-depth understanding of cause and effect relationships and basic mechanistic pathways in medicine. This will enable them to better explain how observed clinical findings develop from preceding pathogenic and pathophysiological events. The pedagogic function of MCD is in relating risk factors, disease entities and morphology, signs and symptoms, and test and procedure findings in a specific case scenario with etiologic pathogenic and pathophysiological sequences within a flow diagram. In this paper, we describe the addition of automation and predetermined lists to further develop the original concept of MCD as described by Engelberg in 1992 and Guerrero in 2001. We demonstrate that with these modifications, MCD is effective and efficient in small group case-based teaching for second-year medical students (ratings of ~3.4 on a 4.0 scale). There was also a significant correlation with other measures of competency, with a 'true' score correlation of 0.54. A traditional calculation of reliability showed promising results (α =0.47) within a low stakes, ungraded environment. Further, we have demonstrated MCD's potential for use in independent learning and TBL. Future studies are needed to evaluate MCD's potential for use in medium stakes assessment or self-paced independent learning and assessment. MCD may be especially relevant in returning students to the application of basic medical science mechanisms in the clinical years.

  4. Heart Failure in South America

    PubMed Central

    Bocchi, Edimar Alcides

    2013-01-01

    Continued assessment of temporal trends in mortality and epidemiology of specific heart failure in South America is needed to provide a scientific basis for rational allocation of the limited health care resources, and strategies to reduce risk and predict the future burden of heart failure. The epidemiology of heart failure in South America was reviewed. Heart failure is the main cause of hospitalization based on available data from approximately 50% of the South American population. The main etiologies of heart failure are ischemic, idiopathic dilated cardiomyopathy, valvular, hypertensive and chagasic etiologies. In endemic areas, Chagas heart disease may be responsible by 41% of the HF cases. Also, heart failure presents high mortality especially in patients with Chagas etiology. Heart failure and etiologies associated with heart failure may be responsible for 6.3% of causes of deaths. Rheumatic fever is the leading cause of valvular heart disease. However, a tendency to reduction of HF mortality due to Chagas heart disease from 1985 to 2006, and reduction in mortality due to HF from 1999 to 2005 were observed in selected states in Brazil. The findings have important public health implications because the allocation of health care resources, and strategies to reduce risk of heart failure should also consider the control of neglected Chagas disease and rheumatic fever in South American countries. PMID:23597301

  5. Identification and assessment of common errors in the admission process of patients in Isfahan Fertility and Infertility Center based on “failure modes and effects analysis”

    PubMed Central

    Dehghan, Ashraf; Abumasoudi, Rouhollah Sheikh; Ehsanpour, Soheila

    2016-01-01

    Background: Infertility and errors in the process of its treatment have a negative impact on infertile couples. The present study was aimed to identify and assess the common errors in the reception process by applying the approach of “failure modes and effects analysis” (FMEA). Materials and Methods: In this descriptive cross-sectional study, the admission process of fertility and infertility center of Isfahan was selected for evaluation of its errors based on the team members’ decision. At first, the admission process was charted through observations and interviewing employees, holding multiple panels, and using FMEA worksheet, which has been used in many researches all over the world and also in Iran. Its validity was evaluated through content and face validity, and its reliability was evaluated through reviewing and confirmation of the obtained information by the FMEA team, and eventually possible errors, causes, and three indicators of severity of effect, probability of occurrence, and probability of detection were determined and corrective actions were proposed. Data analysis was determined by the number of risk priority (RPN) which is calculated by multiplying the severity of effect, probability of occurrence, and probability of detection. Results: Twenty-five errors with RPN ≥ 125 was detected through the admission process, in which six cases of error had high priority in terms of severity and occurrence probability and were identified as high-risk errors. Conclusions: The team-oriented method of FMEA could be useful for assessment of errors and also to reduce the occurrence probability of errors. PMID:28194208

  6. Layout pattern analysis using the Voronoi diagram of line segments

    NASA Astrophysics Data System (ADS)

    Dey, Sandeep Kumar; Cheilaris, Panagiotis; Gabrani, Maria; Papadopoulou, Evanthia

    2016-01-01

    Early identification of problematic patterns in very large scale integration (VLSI) designs is of great value as the lithographic simulation tools face significant timing challenges. To reduce the processing time, such a tool selects only a fraction of possible patterns which have a probable area of failure, with the risk of missing some problematic patterns. We introduce a fast method to automatically extract patterns based on their structure and context, using the Voronoi diagram of line-segments as derived from the edges of VLSI design shapes. Designers put line segments around the problematic locations in patterns called "gauges," along which the critical distance is measured. The gauge center is the midpoint of a gauge. We first use the Voronoi diagram of VLSI shapes to identify possible problematic locations, represented as gauge centers. Then we use the derived locations to extract windows containing the problematic patterns from the design layout. The problematic locations are prioritized by the shape and proximity information of the design polygons. We perform experiments for pattern selection in a portion of a 22-nm random logic design layout. The design layout had 38,584 design polygons (consisting of 199,946 line segments) on layer Mx, and 7079 markers generated by an optical rule checker (ORC) tool. The optical rules specify requirements for printing circuits with minimum dimension. Markers are the locations of some optical rule violations in the layout. We verify our approach by comparing the coverage of our extracted patterns to the ORC-generated markers. We further derive a similarity measure between patterns and between layouts. The similarity measure helps to identify a set of representative gauges that reduces the number of patterns for analysis.

  7. Finding and accessing diagrams in biomedical publications.

    PubMed

    Kuhn, Tobias; Luong, ThaiBinh; Krauthammer, Michael

    2012-01-01

    Complex relationships in biomedical publications are often communicated by diagrams such as bar and line charts, which are a very effective way of summarizing and communicating multi-faceted data sets. Given the ever-increasing amount of published data, we argue that the precise retrieval of such diagrams is of great value for answering specific and otherwise hard-to-meet information needs. To this end, we demonstrate the use of advanced image processing and classification for identifying bar and line charts by the shape and relative location of the different image elements that make up the charts. With recall and precisions of close to 90% for the detection of relevant figures, we discuss the use of this technology in an existing biomedical image search engine, and outline how it enables new forms of literature queries over biomedical relationships that are represented in these charts.

  8. Phase diagram of UCoGe

    NASA Astrophysics Data System (ADS)

    Mineev, V. P.

    2017-03-01

    The temperature-pressure phase diagram of ferromagnetic superconductor UCoGe includes four phase transitions. They are between the paramagnetic and the ferromagnetic states with the subsequent transition in the superconducting ferromagnetic state and between the normal and the superconducting states after which the transition to the superconducting ferromagnetic state has to occur. Here we have developed the Landau theory description of the phase diagram and established the specific ordering arising at each type of transition. The phase transitions to the ferromagnetic superconducting state are inevitably accompanied by the emergence of screening currents. The corresponding magnetostatics considerations allow for establishing the significant difference between the transition from the ferromagnetic to the ferromagnetic superconducting state and the transition from the superconducting to the ferromagnetic superconducting state.

  9. Flamelet Regime Diagram for Turbulent Combustion Simulations

    NASA Astrophysics Data System (ADS)

    Chan, Wai Lee; Ihme, Matthias; Kolla, Hemanth; Chen, Jacqueline

    2016-11-01

    The flamelet model has been widely used in numerical combustion investigations, particularly for the closure of large-eddy simulations (LES) of turbulent reacting flows. In most cases, the simulation results demonstrated good agreements with their experimental counterparts. However, a systematic analysis of the flamelet model's applicability, as well as its potential limitations, is seldom conducted, and the model performance is usually based only on a-posteriori comparisons. The objective of this work is to derive a metric that can formally quantify the suitability of the flamelet model in different flame configurations. For this purpose, a flamelet regime diagram has been developed and studied in the context of direct numerical simulations (DNS) of a turbulent lifted jet flame. The implementation of the regime diagram in LES has been investigated through explicit filtering of the DNS results.

  10. Diagrams of stability of circumbinary planetary systems

    NASA Astrophysics Data System (ADS)

    Popova, Elena

    2014-07-01

    The stability diagrams in the ``pericentric distance - eccentricity'' plane of initial data are built and analyzed for Kepler-38, Kepler-47, and Kepler-64 (PH1). This completes a survey of stability of the known up to now circumbinary planetary systems, initiated by Popova & Shevchenko (2013), where the analysis was performed for Kepler-16, 34, and 35. In the diagrams, the planets appear to be ``embedded'' in the fractal chaos border; however, I make an attempt to measure the ``distance'' to the chaos border in a physically consistent way. The obtained distances are compared to those given by the widely used numerical-experimental criterion by Holman & Wiegert (1999), who employed smooth polynomial approximations to describe the border. I identify the resonance cells, hosting the planets.

  11. Phase diagram of a single lane roundabout

    NASA Astrophysics Data System (ADS)

    Echab, H.; Lakouari, N.; Ez-Zahraouy, H.; Benyoussef, A.

    2016-03-01

    Using the cellular automata model, we numerically study the traffic dynamic in a single lane roundabout system of four entry/exit points. The boundaries are controlled by the injecting rates α1, α2 and the extracting rate β. Both the system with and without Splitter Islands of width Lsp are considered. The phase diagram in the (α1 , β) space and its variation with the roundabout size, Pagg (i.e. the probability of aggressive entry), and Pexit (i.e. the probability of preferential exit) are constructed. The results show that the phase diagram in both cases consists of three phases: free flow, congested and jammed. However, as Lsp increases the free flow phase enlarges while the congested and jammed ones shrink. On the other hand, the short sized roundabout shows better performance in the free flow phase while the large one is more optimal in the congested phase. The density profiles are also investigated.

  12. Modeling the Round Earth through Diagrams

    NASA Astrophysics Data System (ADS)

    Padalkar, Shamin; Ramadas, Jayashree

    Earlier studies have found that students, including adults, have problems understanding the scientifically accepted model of the Sun-Earth-Moon system and explaining day-to-day astronomical phenomena based on it. We have been examining such problems in the context of recent research on visual-spatial reasoning. Working with middle school students in India, we have developed a pedagogical sequence to build the mental model of the Earth and tried it in three schools for socially and educationally disadvantaged students. This pedagogy was developed on the basis of (1) a reading of current research in imagery and visual-spatial reasoning and (2) students' difficulties identified during the course of pretests and interviews. Visual-spatial tools such as concrete (physical) models, gestures, and diagrams are used extensively in the teaching sequence. The building of a mental model is continually integrated with drawing inferences to understand and explain everyday phenomena. The focus of this article is inferences drawn with diagrams.

  13. Prediction of boron carbon nitrogen phase diagram

    NASA Astrophysics Data System (ADS)

    Yao, Sanxi; Zhang, Hantao; Widom, Michael

    We studied the phase diagram of boron, carbon and nitrogen, including the boron-carbon and boron-nitrogen binaries and the boron-carbon-nitrogen ternary. Based on the idea of electron counting and using a technique of mixing similar primitive cells, we constructed many ''electron precise'' structures. First principles calculation is performed on these structures, with either zero or high pressures. For the BN binary, our calculation confirms that a rhmobohedral phase can be stablized at high pressure, consistent with some experimental results. For the BCN ternary, a new ground state structure is discovered and an Ising-like phase transition is suggested. Moreover, we modeled BCN ternary phase diagram and show continuous solubility from boron carbide to the boron subnitride phase.

  14. Penguin diagrams for improved staggered fermions

    SciTech Connect

    Lee, Weonjong

    2005-01-01

    We calculate, at the one-loop level, penguin diagrams for improved staggered fermion operators constructed using various fat links. The main result is that diagonal mixing coefficients with penguin operators are identical between the unimproved operators and the improved operators using such fat links as Fat7, Fat7+Lepage, Fat7, HYP (I) and HYP (II). In addition, it turns out that the off-diagonal mixing vanishes for those constructed using fat links of Fat7, Fat7 and HYP (II). This is a consequence of the fact that the improvement by various fat links changes only the mixing with higher dimension operators and off-diagonal operators. The results of this paper, combined with those for current-current diagrams, provide complete matching at the one-loop level with all corrections of O(g{sup 2}) included.

  15. Phase diagram of silica from computer simulation

    NASA Astrophysics Data System (ADS)

    Saika-Voivod, Ivan; Sciortino, Francesco; Grande, Tor; Poole, Peter H.

    2004-12-01

    We evaluate the phase diagram of the “BKS” potential [van Beest, Kramer, and van Santen, Phys. Rev. Lett. 64, 1955 (1990)], a model of silica widely used in molecular dynamics (MD) simulations. We conduct MD simulations of the liquid, and three crystals ( β -quartz, coesite, and stishovite) over wide ranges of temperature and density, and evaluate the total Gibbs free energy of each phase. The phase boundaries are determined by the intersection of these free energy surfaces. Not unexpectedly for a classical pair potential, our results reveal quantitative discrepancies between the locations of the BKS and real silica phase boundaries. At the same time, we find that the topology of the real phase diagram is reproduced, confirming that the BKS model provides a satisfactory qualitative description of a silicalike material. We also compare the phase boundaries with the locations of liquid-state thermodynamic anomalies identified in previous studies of the BKS model.

  16. Finding and Accessing Diagrams in Biomedical Publications

    PubMed Central

    Kuhn, Tobias; Luong, ThaiBinh; Krauthammer, Michael

    2012-01-01

    Complex relationships in biomedical publications are often communicated by diagrams such as bar and line charts, which are a very effective way of summarizing and communicating multi-faceted data sets. Given the ever-increasing amount of published data, we argue that the precise retrieval of such diagrams is of great value for answering specific and otherwise hard-to-meet information needs. To this end, we demonstrate the use of advanced image processing and classification for identifying bar and line charts by the shape and relative location of the different image elements that make up the charts. With recall and precisions of close to 90% for the detection of relevant figures, we discuss the use of this technology in an existing biomedical image search engine, and outline how it enables new forms of literature queries over biomedical relationships that are represented in these charts. PMID:23304318

  17. Heart failure.

    PubMed

    Braunwald, Eugene

    2013-02-01

    Despite major improvements in the treatment of virtually all cardiac disorders, heart failure (HF) is an exception, in that its prevalence is rising, and only small prolongations in survival are occurring. An increasing fraction, especially older women with diabetes, obesity, and atrial fibrillation exhibit HF with preserved systolic function. Several pathogenetic mechanisms appear to be operative in HF. These include increased hemodynamic overload, ischemia-related dysfunction, ventricular remodeling, excessive neurohumoral stimulation, abnormal myocyte calcium cycling, excessive or inadequate proliferation of the extracellular matrix, accelerated apoptosis, and genetic mutations. Biomarkers released as a consequence of myocardial stretch, imbalance between formation and breakdown of extracellular matrix, inflammation, and renal failure are useful in the identification of the pathogenetic mechanism and, when used in combination, may become helpful in estimating prognosis and selecting appropriate therapy. Promising new therapies that are now undergoing intensive investigation include an angiotensin receptor neprilysin inhibitor, a naturally-occurring vasodilator peptide, a myofilament sensitizer and several drugs that enhance Ca++ uptake by the sarcoplasmic reticulum. Cell therapy, using autologous bone marrow and cardiac progenitor cells, appears to be promising, as does gene therapy. Chronic left ventricular assistance with continuous flow pumps is being applied more frequently and successfully as destination therapy, as a bridge to transplantation, and even as a bridge to recovery and explantation. While many of these therapies will improve the care of patients with HF, significant reductions in prevalence will require vigorous, multifaceted, preventive approaches.

  18. Displaying multimedia environmental partitioning by triangular diagrams

    SciTech Connect

    Lee, S.C.; Mackay, D.

    1995-11-01

    It is suggested that equilateral triangular diagrams are a useful method of depicting the equilibrium partitioning of organic chemicals among the three primary environmental media of the atmosphere, the hydrosphere, and the organosphere (natural organic matter and biotic lipids and waxes). The technique is useful for grouping chemicals into classes according to their partitioning tendencies, for depicting the incremental effects of substituents such as alkyl groups and chlorine, and for showing how partitioning changes in response to changes in temperature.

  19. Phase diagram of a traffic roundabout

    NASA Astrophysics Data System (ADS)

    Huang, Ding-wei

    2007-09-01

    We propose a simple cellular automaton model to study the traffic dynamics in a roundabout. Both numerical and analytical results are presented. We are able to obtain exact solutions in the full parameter space. Exact phase diagrams are derived. When the traffic from two directions mixed, there are only five distinct phases. Some of the combinations from naive intuition are strictly forbidden. We also compare the results to a signaled intersection.

  20. Sketching for Military Courses of Action Diagrams

    DTIC Science & Technology

    2003-01-01

    Course-of- Action Diagrams. Proceedings of the 14th International Workshop on Qualitative Reasoning. Morelia, Mexico . June, 2000. 10. Forbus, K...computational model of sketching. IUI’01, January 14-17, 2001, Santa Fe, New Mexico 15. Forbus, K., Gentner, D. and Law, K. 1995. MAC/FAC: A...Operations 2002. pp. 85- 90. 22. Landay, J. and Myers, B. 1996. Sketching storyboards to illustrate interface behaviors. CHI’96 Conference Companion

  1. Mixed wasted integrated program: Logic diagram

    SciTech Connect

    Mayberry, J.; Stelle, S.; O`Brien, M.; Rudin, M.; Ferguson, J.; McFee, J.

    1994-11-30

    The Mixed Waste Integrated Program Logic Diagram was developed to provide technical alternative for mixed wastes projects for the Office of Technology Development`s Mixed Waste Integrated Program (MWIP). Technical solutions in the areas of characterization, treatment, and disposal were matched to a select number of US Department of Energy (DOE) treatability groups represented by waste streams found in the Mixed Waste Inventory Report (MWIR).

  2. 75 FR 61512 - Outer Continental Shelf Official Protraction Diagrams

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf Official Protraction Diagrams AGENCY: Bureau of Ocean Energy Management, Regulation and Enforcement, Interior. ACTION... Outer Continental Shelf Official Protraction Diagrams (OPDs) located within Atlantic Ocean areas,...

  3. NEW APPROACHES: Using free body diagrams as a diagnostic instrument

    NASA Astrophysics Data System (ADS)

    Whiteley, Peter

    1996-09-01

    A selection of `Free Body Diagrams' were completed by Advanced Level physics students prior to instruction. The diagrams drawn pointed to a range of understandings and conceptions held by the students that might help to guide instructional strategies.

  4. Automated D/3 to Visio Analog Diagrams

    SciTech Connect

    Posey, Stephen B.

    2000-08-10

    ADVAD1 reads an ASCII file containing the D/3 DCS MDL input for analog points for a D/3 continuous database. It uses the information in the files to create a series of Visio files representing the structure of each analog chain, one drawing per Visio file. The actual drawing function is performed by Visio (requires Visio version 4.5+). The user can configure the program to select which fields in the database are shown on the diagram and how the information is to be presented. This gives a visual representation of the structure of the analog chains, showing selected fields in a consistent manner. Updating documentation can be done easily and the automated approach eliminates human error in the cadding process. The program can also create the drawings far faster than a human operator is capable, able to create approximately 270 typical diagrams in about 8 minutes on a Pentium II 400 MHz PC. The program allows for multiple option sets to be saved to provide different settings (i.e., different fields, different field presentations, and /or different diagram layouts) for various scenarios or facilities on one workstation. Option sets may be exported from the Windows registry to allow duplication of settings on another workstation.

  5. Antiferromagnetic phase diagram of the cuprate superconductors

    NASA Astrophysics Data System (ADS)

    Nunes, L. H. C. M.; Teixeira, A. W.; Marino, E. C.

    2017-02-01

    Taking the spin-fermion model as the starting point for describing the cuprate superconductors, we obtain an effective nonlinear sigma-field hamiltonian, which takes into account the effect of doping in the system. We obtain an expression for the spin-wave velocity as a function of the chemical potential. For appropriate values of the parameters we determine the antiferromagnetic phase diagram for the YBa2Cu3O6+x compound as a function of the dopant concentration in good agreement with the experimental data. Furthermore, our approach provides a unified description for the phase diagrams of the hole-doped and the electron doped compounds, which is consistent with the remarkable similarity between the phase diagrams of these compounds, since we have obtained the suppression of the antiferromagnetic phase as the modulus of the chemical potential increases. The aforementioned result then follows by considering positive values of the chemical potential related to the addition of holes to the system, while negative values correspond to the addition of electrons.

  6. Asteroseismic Diagram for Subgiants and Red Giants

    NASA Astrophysics Data System (ADS)

    Gai, Ning; Tang, Yanke; Yu, Peng; Dou, Xianghua

    2017-02-01

    Asteroseismology is a powerful tool for constraining stellar parameters. NASA’s Kepler mission is providing individual eigenfrequencies for a huge number of stars, including thousands of red giants. Besides the frequencies of acoustic modes, an important breakthrough of the Kepler mission is the detection of nonradial gravity-dominated mixed-mode oscillations in red giants. Unlike pure acoustic modes, mixed modes probe deeply into the interior of stars, allowing the stellar core properties and evolution of stars to be derived. In this work, using the gravity-mode period spacing and the large frequency separation, we construct the ΔΠ1–Δν asteroseismic diagram from models of subgiants and red giants with various masses and metallicities. The relationship ΔΠ1–Δν is able to constrain the ages and masses of the subgiants. Meanwhile, for red giants with masses above 1.5 M ⊙, the ΔΠ1–Δν asteroseismic diagram can also work well to constrain the stellar age and mass. Additionally, we calculate the relative “isochrones” τ, which indicate similar evolution states especially for similar mass stars, on the ΔΠ1–Δν diagram.

  7. Nonthermal Radio Emission and the HR Diagram

    NASA Technical Reports Server (NTRS)

    Gibson, D. M.

    1985-01-01

    Perhaps the most reliable indicator of non-radiative heating/momentum in a stellar atmosphere is the presence of nonthermal radio emission. To date, 77 normal stellar objects have been detected and identified as nonthermal sources. These stellar objects are tabulated herein. It is apparent that non-thermal radio emission is not ubiquitous across the HR diagram. This is clearly the case for the single stars; it is not as clear for the binaries unless the radio emission is associated with their late-type components. Choosing to make this association, the single stars and the late-type components are plotted together. The following picture emerges: (1) there are four locations on the HR diagram where non-thermal radio stars are found; (2) the peak incoherent 5 GHz luminosities show a suprisingly small range for stars within each class; (3) the fraction of stellar energy that escapes as radio emission can be estimated by comparing the integrated maximum radio luminosity to the bolometric luminosity; (4) there are no apparent differences in L sub R between binaries with two cool components, binaries with one hot and one cool component, and single stars for classes C and D; and (5) The late-type stars (classes B, C, and D) are located in parts of the HR diagram where there is reason to suspect that the surfaces of the stars are being braked with respect to their interiors.

  8. The Critical Importance of Russell's Diagram

    NASA Astrophysics Data System (ADS)

    Gingerich, O.

    2013-04-01

    The idea of dwarf and giants stars, but not the nomenclature, was first established by Eijnar Hertzsprung in 1905; his first diagrams in support appeared in 1911. In 1913 Henry Norris Russell could demonstrate the effect far more strikingly because he measured the parallaxes of many stars at Cambridge, and could plot absolute magnitude against spectral type for many points. The general concept of dwarf and giant stars was essential in the galactic structure work of Harlow Shapley, Russell's first graduate student. In order to calibrate the period-luminosity relation of Cepheid variables, he was obliged to fall back on statistical parallax using only 11 Cepheids, a very sparse sample. Here the insight provided by the Russell diagram became critical. The presence of yellow K giant stars in globular clusters credentialed his calibration of the period-luminosity relation by showing that the calibrated luminosity of the Cepheids was comparable to the luminosity of the K giants. It is well known that in 1920 Shapley did not believe in the cosmological distances of Heber Curtis' spiral nebulae. It is not so well known that in 1920 Curtis' plot of the period-luminosity relation suggests that he didn't believe it was a physical relation and also he failed to appreciate the significance of the Russell diagram for understanding the large size of the Milky Way.

  9. Massive basketball diagram for a thermal scalar field theory

    NASA Astrophysics Data System (ADS)

    Andersen, Jens O.; Braaten, Eric; Strickland, Michael

    2000-08-01

    The ``basketball diagram'' is a three-loop vacuum diagram for a scalar field theory that cannot be expressed in terms of one-loop diagrams. We calculate this diagram for a massive scalar field at nonzero temperature, reducing it to expressions involving three-dimensional integrals that can be easily evaluated numerically. We use this result to calculate the free energy for a massive scalar field with a φ4 interaction to three-loop order.

  10. Measuring subjective complaints of attention and performance failures - development and psychometric validation in tinnitus of the self-assessment scale APSA

    PubMed Central

    2013-01-01

    Background There is a need for a validated self-assessment questionnaire for cognitive impairment in subjects reporting subjective tinnitus. The objective was to develop a patient-reported outcome measure. Methods This was a prospective, non-interventional, multicultural study. The 30-item “Attention and Performance Self-Assessment Scale” (APSA) was linguistically validated in Germany, Mexico and USA and was analyzed for content and structure. The analysis included descriptive statistics of baseline data, item characteristics, test-retest reliability (intra-class correlation coefficients, ICC), definition of internal consistency (Cronbach’ s alpha), and explorative and confirmatory factor analysis to define the structure of the scale. Correlations with various tinnitus scales and subscales from the Hospital Anxiety and Depression Scale (HADS) were done to estimate convergent validity. Results The data for 211 subjects aged 30 through 60 years, (mean= 48.5 years, SD= 8.3) with mild to moderate tinnitus (mean Tinnitus Handicap Inventory-12 (THI-12) total score 11.2, SD= 5.3) were analyzed. The majority of subjects had sub-clinical scores for anxiety and depression (HADS below 11 points). Sequential principal factor analyses of the APSA resulted in a subscale which included 20 (APS20) of the original 30 items and two correlated subscales (AP-F1, AP-F2) defined by 9 items each. Both factor solutions were confirmed by confirmatory factor analysis. Test retest reliability of the APS20, AP-F1 and AP-F2 (ICC ≥ 0.87) and internal consistency (Cronbach’s alpha ≥ 0.89) are high. APS20 correlated moderately high with HADS (depression: 0.54; anxiety: 0.62) and THI-12 total (0.52). In a few cases, AP-F2 correlated higher than AP-F1 with other scales (e.g. HADS-depression with AP-F1: only 0.46, but AP-F2: 0.59). Conclusions APS20, AP-F1, and AP-F2 have good psychometrical properties. The scales will add value to the assessment of cognitive aspects of quality

  11. Students' Learning Activities While Studying Biological Process Diagrams

    ERIC Educational Resources Information Center

    Kragten, Marco; Admiraal, Wilfried; Rijlaarsdam, Gert

    2015-01-01

    Process diagrams describe how a system functions (e.g. photosynthesis) and are an important type of representation in Biology education. In the present study, we examined students' learning activities while studying process diagrams, related to their resulting comprehension of these diagrams. Each student completed three learning tasks. Verbal…

  12. Oak Ridge National Laboratory Technology Logic Diagram. Executive Summary

    SciTech Connect

    Not Available

    1993-06-30

    This executive summary contains a description of the logic diagram format; some examples from the diagram (Vol. 2) and associated technology evaluation data sheets (Vol. 3); a complete (albeit condensed) listing of the RA, D&D, and WM problems at ORNL; and a complete listing of the technology rankings for all the areas covered by the diagram.

  13. Science Visual Literacy: Learners' Perceptions and Knowledge of Diagrams

    ERIC Educational Resources Information Center

    McTigue, Erin M.; Flowers, Amanda C.

    2011-01-01

    Constructing meaning from science texts relies not only on comprehending the words but also the diagrams and other graphics. The goal of this study was to explore elementary students' perceptions of science diagrams and their skills related to diagram interpretation. 30 students, ranging from second grade through middle school, completed a diagram…

  14. Failure environment analysis tool applications

    NASA Technical Reports Server (NTRS)

    Pack, Ginger L.; Wadsworth, David B.

    1994-01-01

    Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instilled within it, the determination to preserve the integrity of the systems upon which our mission and, our employees lives and well-being depend. One of the ways this is being done is by expanding and improving the tools used to perform risk assessment. The Failure Environment Analysis Tool (FEAT) was developed to help engineers and analysts more thoroughly and reliably conduct risk assessment and failure analysis. FEAT accomplishes this by providing answers to questions regarding what might have caused a particular failure; or, conversely, what effect the occurrence of a failure might have on an entire system. Additionally, FEAT can determine what common causes could have resulted in other combinations of failures. FEAT will even help determine the vulnerability of a system to failures, in light of reduced capability. FEAT also is useful in training personnel who must develop an understanding of particular systems. FEAT facilitates training on system behavior, by providing an automated environment in which to conduct 'what-if' evaluation. These types of analyses make FEAT a valuable tool for engineers and operations personnel in the design, analysis, and operation of NASA space systems.

  15. Failure environment analysis tool applications

    NASA Technical Reports Server (NTRS)

    Pack, Ginger L.; Wadsworth, David B.

    1993-01-01

    Understanding risks and avoiding failure are daily concerns for the women and men of NASA. Although NASA's mission propels us to push the limits of technology, and though the risks are considerable, the NASA community has instilled within, the determination to preserve the integrity of the systems upon which our mission and, our employees lives and well-being depend. One of the ways this is being done is by expanding and improving the tools used to perform risk assessment. The Failure Environment Analysis Tool (FEAT) was developed to help engineers and analysts more thoroughly and reliably conduct risk assessment and failure analysis. FEAT accomplishes this by providing answers to questions regarding what might have caused a particular failure; or, conversely, what effect the occurrence of a failure might have on an entire system. Additionally, FEAT can determine what common causes could have resulted in other combinations of failures. FEAT will even help determine the vulnerability of a system to failures, in light of reduced capability. FEAT also is useful in training personnel who must develop an understanding of particular systems. FEAT facilitates training on system behavior, by providing an automated environment in which to conduct 'what-if' evaluation. These types of analyses make FEAT a valuable tool for engineers and operations personnel in the design, analysis, and operation of NASA space systems.

  16. Failure and recovery in dynamical networks

    PubMed Central

    Böttcher, L.; Luković, M.; Nagler, J.; Havlin, S.; Herrmann, H. J.

    2017-01-01

    Failure, damage spread and recovery crucially underlie many spatially embedded networked systems ranging from transportation structures to the human body. Here we study the interplay between spontaneous damage, induced failure and recovery in both embedded and non-embedded networks. In our model the network’s components follow three realistic processes that capture these features: (i) spontaneous failure of a component independent of the neighborhood (internal failure), (ii) failure induced by failed neighboring nodes (external failure) and (iii) spontaneous recovery of a component. We identify a metastable domain in the global network phase diagram spanned by the model’s control parameters where dramatic hysteresis effects and random switching between two coexisting states are observed. This dynamics depends on the characteristic link length of the embedded system. For the Euclidean lattice in particular, hysteresis and switching only occur in an extremely narrow region of the parameter space compared to random networks. We develop a unifying theory which links the dynamics of our model to contact processes. Our unifying framework may help to better understand controllability in spatially embedded and random networks where spontaneous recovery of components can mitigate spontaneous failure and damage spread in dynamical networks. PMID:28155876

  17. Failure and recovery in dynamical networks

    NASA Astrophysics Data System (ADS)

    Böttcher, L.; Luković, M.; Nagler, J.; Havlin, S.; Herrmann, H. J.

    2017-02-01

    Failure, damage spread and recovery crucially underlie many spatially embedded networked systems ranging from transportation structures to the human body. Here we study the interplay between spontaneous damage, induced failure and recovery in both embedded and non-embedded networks. In our model the network’s components follow three realistic processes that capture these features: (i) spontaneous failure of a component independent of the neighborhood (internal failure), (ii) failure induced by failed neighboring nodes (external failure) and (iii) spontaneous recovery of a component. We identify a metastable domain in the global network phase diagram spanned by the model’s control parameters where dramatic hysteresis effects and random switching between two coexisting states are observed. This dynamics depends on the characteristic link length of the embedded system. For the Euclidean lattice in particular, hysteresis and switching only occur in an extremely narrow region of the parameter space compared to random networks. We develop a unifying theory which links the dynamics of our model to contact processes. Our unifying framework may help to better understand controllability in spatially embedded and random networks where spontaneous recovery of components can mitigate spontaneous failure and damage spread in dynamical networks.

  18. Comparison of Proposed Modified and Original Sequential Organ Failure Assessment Scores in Predicting ICU Mortality: A Prospective, Observational, Follow-Up Study

    PubMed Central

    Gholipour Baradari, Afshin; Daneshiyan, Maryam; Aarabi, Mohsen; Talebiyan Kiakolaye, Yaser; Nouraei, Seyed Mahmood; Zamani Kiasari, Alieh; Habibi, Mohammad Reza; Emami Zeydi, Amir; Sadeghi, Faegheh

    2016-01-01

    Background. The sequential organ failure assessment (SOFA) score has been recommended to triage critically ill patients in the intensive care unit (ICU). This study aimed to compare the performance of our proposed MSOFA and original SOFA scores in predicting ICU mortality. Methods. This prospective observational study was conducted on 250 patients admitted to the ICU. Both tools scores were calculated at the beginning, 24 hours of ICU admission, and 48 hours of ICU admission. Diagnostic odds ratio and receiver operating characteristic (ROC) curve were used to compare the two scores. Results. MSOFA and SOFA predicted mortality similarly with an area under the ROC curve of 0.837, 0.992, and 0.977 for MSOFA 1, MSOFA 2, and MSOFA 3, respectively, and 0.857, 0.988, and 0.988 for SOFA 1, SOFA 2, and SOFA 3, respectively. The sensitivity and specificity of MSOFA 1 in cut-off point 8 were 82.9% and 68.4%, respectively, MSOFA 2 in cut-off point 9.5 were 94.7% and 97.1%, respectively, and MSOFA 3 in cut-off point of 9.3 were 97.4% and 93.1%, respectively. There was a significant positive correlation between the MSOFA 1 and the SOFA 1 (r: 0.942), 24 hours (r: 0.972), and 48 hours (r: 0.960). Conclusion. The proposed MSOFA and the SOFA scores had high diagnostic accuracy, sensitivity, and specificity for predicting mortality. PMID:28116220

  19. Usefulness of Combining Galectin-3 and BIVA Assessments in Predicting Short- and Long-Term Events in Patients Admitted for Acute Heart Failure

    PubMed Central

    De Berardinis, Benedetta; Magrini, Laura; Zampini, Giorgio; Zancla, Benedetta; Salerno, Gerardo; Cardelli, Patrizia; Di Stasio, Enrico; Gaggin, Hanna K.; Belcher, Arianna; Parry, Blair A.; Nagurney, John T.; Januzzi, James L.; Di Somma, Salvatore

    2014-01-01

    Introduction. Acute heart failure (AHF) is associated with a higher risk for the occurrence of rehospitalization and death. Galectin-3 (GAL3) is elevated in AHF patients and is an indicator in predicting short-term mortality. The total body water using bioimpedance vector analysis (BIVA) is able to identify mortality within AHF patients. The aim of this study was to evaluate the short- and long-term predictive value of GAL3, BIVA, and the combination of both in AHF patients in Emergency Department (ED). Methods. 205 ED patients with AHF were evaluated by testing for B type natriuretic peptide (BNP) and GAL3. The primary endpoint was death and rehospitalization at 30, 60, 90, and 180 days and 12 and 18 months. AHF patients were evaluated at the moment of ED arrival with clinical judgment and GAL3 and BIVA measurement. Results. GAL3 level was significantly higher in patients >71 years old, and with eGFR < 30 cc/min. The area under the curve (AUC) of GAL3 + BIVA, GAL3 and BIVA for death and rehospitalization both when considered in total and when considered serially for the follow-up period showed that the combination has a better prognostic value. Kaplan-Meier survival curve for GAL3 values >17.8 ng/mL shows significant survival difference. At multivariate Cox regression analysis GAL3 is an independent variable to predict death + rehospitalization with a value of 32.24 ng/mL at 30 days (P < 0.005). Conclusion. In patients admitted for AHF an early assessment of GAL3 and BIVA seems to be useful in identifying patients at high risk for death and rehospitalization at short and long term. Combining the biomarker and the device could be of great utility since they monitor the severity of two pathophysiological different mechanisms: heart fibrosis and fluid overload. PMID:25101304

  20. Revisiting Stress Corrosion Cracking of Steel in Caustic Solutions for Developing Cracking Susceptibility Diagrams for Improved Applicability

    NASA Astrophysics Data System (ADS)

    Pal, Sarvesh; Raman, R. K. Singh; Ibrahim, R. N.

    2012-06-01

    Stress corrosion cracking tests were conducted using Bayer solutions of different chemistry at different temperatures for extraction of alumina from bauxite ores. The validity of the commonly used caustic cracking susceptibility (CS) diagram for steels exposed to plain caustic solutions was assessed by testing the notched and precracked specimens. This study presents first results toward the development of a model susceptibility diagram for actual Bayer solutions, and for improved applicability of the traditional plain caustic diagram. For mechanistic understanding of caustic cracking, tests were also carried out under imposed electrochemical conditions.

  1. Sinc function representation and three-loop master diagrams

    SciTech Connect

    Easther, Richard; Guralnik, Gerald; Hahn, Stephen

    2001-04-15

    We test the Sinc function representation, a novel method for numerically evaluating Feynman diagrams, by using it to evaluate the three-loop master diagrams. Analytical results have been obtained for all these diagrams, and we find excellent agreement between our calculations and the exact values. The Sinc function representation converges rapidly, and it is straightforward to obtain accuracies of 1 part in 10{sup 6} for these diagrams and with longer runs we found results better than 1 part in 10{sup 12}. Finally, this paper extends the Sinc function representation to diagrams containing massless propagators.

  2. Generic Phase Diagram of Binary Superlattices

    NASA Astrophysics Data System (ADS)

    Tkachenko, Alexei

    Emergence of a large variety of self-assembled superlattices is a dramatic recent trend in the fields of nanoparticle and colloidal sciences. Motivated by this development, we propose a model that combines simplicity with a remarkably rich phase behavior, applicable to a wide range of such self-assembled systems. Those include nanoparticle and colloidal assemblies driven by DNA-mediated interactions, electrostatics, and possibly, by controlled drying. In our model, a binary system of Large and Small hard sphere (L and S)interact via selective short-range (''sticky'') attraction. In its simplest version, this Binary Sticky Sphere model features attraction only between 'S' and 'L' particles, respectively. We demonstrate that in the limit when this attraction is sufficiently strong compared to kT, the problem becomes purely geometrical: the thermodynamically preferred state should maximize the number of S-L contacts. A general procedure for constructing the phase diagram as a function of system composition f, and particle size ratio r, is outlined. In this way, the global phase behavior can be calculated very efficiently, for a given set of plausible candidate phases. Furthermore, the geometric nature of the problem enables us to generate those candidate phases through a well defined and intuitive construction. We calculate the phase diagrams both for 2D and 3D systems, and compare the results with existing experiments. Most of the 3D superlattices observed to date are featured in our phase diagram, while several more are yet to be discovered. The research was carried out at the CFN, DOE Office of Science Facility, at BNL, under Contract No. DE-SC0012704.

  3. State-transition diagrams for biologists.

    PubMed

    Bersini, Hugues; Klatzmann, David; Six, Adrien; Thomas-Vaslin, Véronique

    2012-01-01

    It is clearly in the tradition of biologists to conceptualize the dynamical evolution of biological systems in terms of state-transitions of biological objects. This paper is mainly concerned with (but obviously not limited too) the immunological branch of biology and shows how the adoption of UML (Unified Modeling Language) state-transition diagrams can ease the modeling, the understanding, the coding, the manipulation or the documentation of population-based immune software model generally defined as a set of ordinary differential equations (ODE), describing the evolution in time of populations of various biological objects. Moreover, that same UML adoption naturally entails a far from negligible representational economy since one graphical item of the diagram might have to be repeated in various places of the mathematical model. First, the main graphical elements of the UML state-transition diagram and how they can be mapped onto a corresponding ODE mathematical model are presented. Then, two already published immune models of thymocyte behavior and time evolution in the thymus, the first one originally conceived as an ODE population-based model whereas the second one as an agent-based one, are refactored and expressed in a state-transition form so as to make them much easier to understand and their respective code easier to access, to modify and run. As an illustrative proof, for any immunologist, it should be possible to understand faithfully enough what the two software models are supposed to reproduce and how they execute with no need to plunge into the Java or Fortran lines.

  4. State-Transition Diagrams for Biologists

    PubMed Central

    Bersini, Hugues; Klatzmann, David; Six, Adrien; Thomas-Vaslin, Véronique

    2012-01-01

    It is clearly in the tradition of biologists to conceptualize the dynamical evolution of biological systems in terms of state-transitions of biological objects. This paper is mainly concerned with (but obviously not limited too) the immunological branch of biology and shows how the adoption of UML (Unified Modeling Language) state-transition diagrams can ease the modeling, the understanding, the coding, the manipulation or the documentation of population-based immune software model generally defined as a set of ordinary differential equations (ODE), describing the evolution in time of populations of various biological objects. Moreover, that same UML adoption naturally entails a far from negligible representational economy since one graphical item of the diagram might have to be repeated in various places of the mathematical model. First, the main graphical elements of the UML state-transition diagram and how they can be mapped onto a corresponding ODE mathematical model are presented. Then, two already published immune models of thymocyte behavior and time evolution in the thymus, the first one originally conceived as an ODE population-based model whereas the second one as an agent-based one, are refactored and expressed in a state-transition form so as to make them much easier to understand and their respective code easier to access, to modify and run. As an illustrative proof, for any immunologist, it should be possible to understand faithfully enough what the two software models are supposed to reproduce and how they execute with no need to plunge into the Java or Fortran lines. PMID:22844438

  5. Comprehending 3D Diagrams: Sketching to Support Spatial Reasoning.

    PubMed

    Gagnier, Kristin M; Atit, Kinnari; Ormand, Carol J; Shipley, Thomas F

    2016-11-25

    Science, technology, engineering, and mathematics (STEM) disciplines commonly illustrate 3D relationships in diagrams, yet these are often challenging for students. Failing to understand diagrams can hinder success in STEM because scientific practice requires understanding and creating diagrammatic representations. We explore a new approach to improving student understanding of diagrams that convey 3D relations that is based on students generating their own predictive diagrams. Participants' comprehension of 3D spatial diagrams was measured in a pre- and post-design where students selected the correct 2D slice through 3D geologic block diagrams. Generating sketches that predicated the internal structure of a model led to greater improvement in diagram understanding than visualizing the interior of the model without sketching, or sketching the model without attempting to predict unseen spatial relations. In addition, we found a positive correlation between sketched diagram accuracy and improvement on the diagram comprehension measure. Results suggest that generating a predictive diagram facilitates students' abilities to make inferences about spatial relationships in diagrams. Implications for use of sketching in supporting STEM learning are discussed.

  6. Algorithms for Disconnected Diagrams in Lattice QCD

    SciTech Connect

    Gambhir, Arjun Singh; Stathopoulos, Andreas; Orginos, Konstantinos; Yoon, Boram; Gupta, Rajan; Syritsyn, Sergey

    2016-11-01

    Computing disconnected diagrams in Lattice QCD (operator insertion in a quark loop) entails the computationally demanding problem of taking the trace of the all to all quark propagator. We first outline the basic algorithm used to compute a quark loop as well as improvements to this method. Then, we motivate and introduce an algorithm based on the synergy between hierarchical probing and singular value deflation. We present results for the chiral condensate using a 2+1-flavor clover ensemble and compare estimates of the nucleon charges with the basic algorithm.

  7. On critical exponents without Feynman diagrams

    NASA Astrophysics Data System (ADS)

    Sen, Kallol; Sinha, Aninda

    2016-11-01

    In order to achieve a better analytic handle on the modern conformal bootstrap program, we re-examine and extend the pioneering 1974 work of Polyakov’s, which was based on consistency between the operator product expansion and unitarity. As in the bootstrap approach, this method does not depend on evaluating Feynman diagrams. We show how this approach can be used to compute the anomalous dimensions of certain operators in the O(n) model at the Wilson-Fisher fixed point in 4-ɛ dimensions up to O({ɛ }2). AS dedicates this work to the loving memory of his mother.

  8. The Mental Health Outcomes of Drought: A Systematic Review and Causal Process Diagram.

    PubMed

    Vins, Holly; Bell, Jesse; Saha, Shubhayu; Hess, Jeremy J

    2015-10-22

    Little is understood about the long term, indirect health consequences of drought (a period of abnormally dry weather). In particular, the implications of drought for mental health via pathways such as loss of livelihood, diminished social support, and rupture of place bonds have not been extensively studied, leaving a knowledge gap for practitioners and researchers alike. A systematic review of literature was performed to examine the mental health effects of drought. The systematic review results were synthesized to create a causal process diagram that illustrates the pathways linking drought effects to mental health outcomes. Eighty-two articles using a variety of methods in different contexts were gathered from the systematic review. The pathways in the causal process diagram with greatest support in the literature are those focusing on the economic and migratory effects of drought. The diagram highlights the complexity of the relationships between drought and mental health, including the multiple ways that factors can interact and lead to various outcomes. The systematic review and resulting causal process diagram can be used in both practice and theory, including prevention planning, public health programming, vulnerability and risk assessment, and research question guidance. The use of a causal process diagram provides a much needed avenue for integrating the findings of diverse research to further the understanding of the mental health implications of drought.

  9. The Mental Health Outcomes of Drought: A Systematic Review and Causal Process Diagram

    PubMed Central

    Vins, Holly; Bell, Jesse; Saha, Shubhayu; Hess, Jeremy J.

    2015-01-01

    Little is understood about the long term, indirect health consequences of drought (a period of abnormally dry weather). In particular, the implications of drought for mental health via pathways such as loss of livelihood, diminished social support, and rupture of place bonds have not been extensively studied, leaving a knowledge gap for practitioners and researchers alike. A systematic review of literature was performed to examine the mental health effects of drought. The systematic review results were synthesized to create a causal process diagram that illustrates the pathways linking drought effects to mental health outcomes. Eighty-two articles using a variety of methods in different contexts were gathered from the systematic review. The pathways in the causal process diagram with greatest support in the literature are those focusing on the economic and migratory effects of drought. The diagram highlights the complexity of the relationships between drought and mental health, including the multiple ways that factors can interact and lead to various outcomes. The systematic review and resulting causal process diagram can be used in both practice and theory, including prevention planning, public health programming, vulnerability and risk assessment, and research question guidance. The use of a causal process diagram provides a much needed avenue for integrating the findings of diverse research to further the understanding of the mental health implications of drought. PMID:26506367

  10. Variation in Cognitive Failures: An Individual Differences Investigation of Everyday Attention and Memory Failures

    ERIC Educational Resources Information Center

    Unsworth, Nash; Brewer, Gene A.; Spillers, Gregory J.

    2012-01-01

    The present study examined individual differences in everyday cognitive failures assessed by diaries. A large sample of participants completed various cognitive ability measures in the laboratory. Furthermore, a subset of these participants also recorded everyday cognitive failures (attention, retrospective memory, and prospective memory failures)…

  11. Effects of Student-Generated Diagrams versus Student-Generated Summaries on Conceptual Understanding of Causal and Dynamic Knowledge in Plate Tectonics.

    ERIC Educational Resources Information Center

    Gobert, Janice D.; Clement, John J.

    1999-01-01

    Grade five students' (n=58) conceptual understanding of plate tectonics was measured by analysis of student-generated summaries and diagrams, and by posttest assessment of both the spatial/static and causal/dynamic aspects of the domain. The diagram group outperformed the summary and text-only groups on the posttest measures. Discusses the effects…

  12. Identifying Liquid-Gas System Misconceptions and Addressing Them Using a Laboratory Exercise on Pressure-Temperature Diagrams of a Mixed Gas Involving Liquid-Vapor Equilibrium

    ERIC Educational Resources Information Center

    Yoshikawa, Masahiro; Koga, Nobuyoshi

    2016-01-01

    This study focuses on students' understandings of a liquid-gas system with liquid-vapor equilibrium in a closed system using a pressure-temperature ("P-T") diagram. By administrating three assessment questions concerning the "P-T" diagrams of liquid-gas systems to students at the beginning of undergraduate general chemistry…

  13. Revisiting the phase diagram of hard ellipsoids

    NASA Astrophysics Data System (ADS)

    Odriozola, Gerardo

    2012-04-01

    In this work, the well-known Frenkel-Mulder phase diagram of hard ellipsoids of revolution [D. Frenkel and B. M. Mulder, Mol. Phys. 55, 1171 (1985), 10.1080/00268978500101971] is revisited by means of replica exchange Monte Carlo simulations. The method provides good sampling of dense systems and so, solid phases can be accessed without the need of imposing a given structure. At high densities, we found plastic solids and fcc-like crystals for semi-spherical ellipsoids (prolates and oblates), and SM2 structures [P. Pfleiderer and T. Schilling, Phys. Rev. E 75, 020402 (2007)] for x : 1-prolates and 1 : x-oblates with x ≥ 3. The revised fluid-crystal and isotropic-nematic transitions reasonably agree with those presented in the Frenkel-Mulder diagram. An interesting result is that, for small system sizes (100 particles), we obtained 2:1- and 1.5:1-prolate equations of state without transitions, while some order is developed at large densities. Furthermore, the symmetric oblate cases are also reluctant to form ordered phases.

  14. Critical point analysis of phase envelope diagram

    NASA Astrophysics Data System (ADS)

    Soetikno, Darmadi; Kusdiantara, Rudy; Puspita, Dila; Sidarto, Kuntjoro A.; Siagian, Ucok W. R.; Soewono, Edy; Gunawan, Agus Y.

    2014-03-01

    Phase diagram or phase envelope is a relation between temperature and pressure that shows the condition of equilibria between the different phases of chemical compounds, mixture of compounds, and solutions. Phase diagram is an important issue in chemical thermodynamics and hydrocarbon reservoir. It is very useful for process simulation, hydrocarbon reactor design, and petroleum engineering studies. It is constructed from the bubble line, dew line, and critical point. Bubble line and dew line are composed of bubble points and dew points, respectively. Bubble point is the first point at which the gas is formed when a liquid is heated. Meanwhile, dew point is the first point where the liquid is formed when the gas is cooled. Critical point is the point where all of the properties of gases and liquids are equal, such as temperature, pressure, amount of substance, and others. Critical point is very useful in fuel processing and dissolution of certain chemicals. Here in this paper, we will show the critical point analytically. Then, it will be compared with numerical calculations of Peng-Robinson equation by using Newton-Raphson method. As case studies, several hydrocarbon mixtures are simulated using by Matlab.

  15. Phase diagrams of disordered Weyl semimetals

    NASA Astrophysics Data System (ADS)

    Shapourian, Hassan; Hughes, Taylor L.

    2016-02-01

    Weyl semimetals are gapless quasitopological materials with a set of isolated nodal points forming their Fermi surface. They manifest their quasitopological character in a series of topological electromagnetic responses including the anomalous Hall effect. Here, we study the effect of disorder on Weyl semimetals while monitoring both their nodal/semimetallic and topological properties through computations of the localization length and the Hall conductivity. We examine three different lattice tight-binding models which realize the Weyl semimetal in part of their phase diagram and look for universal features that are common to all of the models, and interesting distinguishing features of each model. We present detailed phase diagrams of these models for large system sizes and we find that weak disorder preserves the nodal points up to the diffusive limit, but does affect the Hall conductivity. We show that the trend of the Hall conductivity is consistent with an effective picture in which disorder causes the Weyl nodes move within the Brillouin zone along a specific direction that depends deterministically on the properties of the model and the neighboring phases to the Weyl semimetal phase. We also uncover an unusual (nonquantized) anomalous Hall insulator phase which can only exist in the presence of disorder.

  16. Ab initio phase diagram of iridium

    NASA Astrophysics Data System (ADS)

    Burakovsky, L.; Burakovsky, N.; Cawkwell, M. J.; Preston, D. L.; Errandonea, D.; Simak, S. I.

    2016-09-01

    The phase diagram of iridium is investigated using the Z methodology. The Z methodology is a technique for phase diagram studies that combines the direct Z method for the computation of melting curves and the inverse Z method for the calculation of solid-solid phase boundaries. In the direct Z method, the solid phases along the melting curve are determined by comparing the solid-liquid equilibrium boundaries of candidate crystal structures. The inverse Z method involves quenching the liquid into the most stable solid phase at various temperatures and pressures to locate a solid-solid boundary. Although excellent agreement with the available experimental data (to ≲65 GPa) is found for the equation of state (EOS) of Ir, it is the third-order Birch-Murnaghan EOS with B0'=5 rather than the more widely accepted B0'=4 that describes our ab initio data to higher pressure (P ) . Our results suggest the existence of a random-stacking hexagonal close-packed structure of iridium at high P . We offer an explanation for the 14-layer hexagonal structure observed in experiments by Cerenius and Dubrovinsky.

  17. Instability Regions in the Upper HR Diagram

    NASA Technical Reports Server (NTRS)

    deJager, Cornelis; Lobel, Alex; Nieuwenhuijzen, Hans; Stothers, Richard; Hansen, James E. (Technical Monitor)

    2001-01-01

    The following instability regions for blueward evolving supergiants are outlined and compared: (1) Areas in the Hertzsprung-Russell(HR) diagram where stars are dynamically unstable. (2) Areas where the effective acceleration in the upper part of the photospheres is negative, hence directed outward. (3) Areas where the sonic points of the stellar wind (Where wind velocity = sound velocity) are situated inside the photospheres, at a level deeper than tau(sub Ross) = 0.01. We compare the results with the positions of actual stars in the HR diagram and we find evidence that the recent strong contraction of the yellow hypergiant HR8752 was initiated in a period during which (g(sub eff)) is less than 0, whereupon the star became dynamically unstable. The instability and extreme shells around IRC+10420 are suggested to be related to three factors: (g(sub eff)) is less than 0; the sonic point is situated inside the photosphere; and the star is dynamically unstable.

  18. Revisiting the phase diagram of hard ellipsoids.

    PubMed

    Odriozola, Gerardo

    2012-04-07

    In this work, the well-known Frenkel-Mulder phase diagram of hard ellipsoids of revolution [D. Frenkel and B. M. Mulder, Mol. Phys. 55, 1171 (1985)] is revisited by means of replica exchange Monte Carlo simulations. The method provides good sampling of dense systems and so, solid phases can be accessed without the need of imposing a given structure. At high densities, we found plastic solids and fcc-like crystals for semi-spherical ellipsoids (prolates and oblates), and SM2 structures [P. Pfleiderer and T. Schilling, Phys. Rev. E 75, 020402 (2007)] for x : 1-prolates and 1 : x-oblates with x ≥ 3. The revised fluid-crystal and isotropic-nematic transitions reasonably agree with those presented in the Frenkel-Mulder diagram. An interesting result is that, for small system sizes (100 particles), we obtained 2:1- and 1.5:1-prolate equations of state without transitions, while some order is developed at large densities. Furthermore, the symmetric oblate cases are also reluctant to form ordered phases.

  19. Critical point analysis of phase envelope diagram

    SciTech Connect

    Soetikno, Darmadi; Siagian, Ucok W. R.; Kusdiantara, Rudy Puspita, Dila Sidarto, Kuntjoro A. Soewono, Edy; Gunawan, Agus Y.

    2014-03-24

    Phase diagram or phase envelope is a relation between temperature and pressure that shows the condition of equilibria between the different phases of chemical compounds, mixture of compounds, and solutions. Phase diagram is an important issue in chemical thermodynamics and hydrocarbon reservoir. It is very useful for process simulation, hydrocarbon reactor design, and petroleum engineering studies. It is constructed from the bubble line, dew line, and critical point. Bubble line and dew line are composed of bubble points and dew points, respectively. Bubble point is the first point at which the gas is formed when a liquid is heated. Meanwhile, dew point is the first point where the liquid is formed when the gas is cooled. Critical point is the point where all of the properties of gases and liquids are equal, such as temperature, pressure, amount of substance, and others. Critical point is very useful in fuel processing and dissolution of certain chemicals. Here in this paper, we will show the critical point analytically. Then, it will be compared with numerical calculations of Peng-Robinson equation by using Newton-Raphson method. As case studies, several hydrocarbon mixtures are simulated using by Matlab.

  20. A Markov Model for Assessing the Reliability of a Digital Feedwater Control System

    SciTech Connect

    Chu,T.L.; Yue, M.; Martinez-Guridi, G.; Lehner, J.

    2009-02-11

    A Markov approach has been selected to represent and quantify the reliability model of a digital feedwater control system (DFWCS). The system state, i.e., whether a system fails or not, is determined by the status of the components that can be characterized by component failure modes. Starting from the system state that has no component failure, possible transitions out of it are all failure modes of all components in the system. Each additional component failure mode will formulate a different system state that may or may not be a system failure state. The Markov transition diagram is developed by strictly following the sequences of component failures (i.e., failure sequences) because the different orders of the same set of failures may affect the system in completely different ways. The formulation and quantification of the Markov model, together with the proposed FMEA (Failure Modes and Effects Analysis) approach, and the development of the supporting automated FMEA tool are considered the three major elements of a generic conceptual framework under which the reliability of digital systems can be assessed.

  1. Diagrams: A Visual Survey of Graphs, Maps, Charts and Diagrams for the Graphic Designer.

    ERIC Educational Resources Information Center

    Lockwood, Arthur

    Since the ultimate success of any diagram rests in its clarity, it is important that the designer select a method of presentation which will achieve this aim. He should be aware of the various ways in which statistics can be shown diagrammatically, how information can be incorporated in maps, and how events can be plotted in chart or graph form.…

  2. Heuristics Diagrams as a Tool to Formatively Assess Teachers' Research

    ERIC Educational Resources Information Center

    Chamizo, J. A.; Garcia-Franco, A.

    2013-01-01

    Many teacher education programs include different forms of teachers doing research. Be it in the form of action research or general inquiries about their practice, it has been argued that when teachers do research on their own practice, they are able to take a more reflective stance towards their work which is necessary to bring about educational…

  3. Multi-rater Agreement in the Assessment of Anterior Cruciate Ligament Reconstruction Failure. A Radiographic and Video Analysis of the MARS Cohort

    PubMed Central

    Matava, Matthew J.; Arciero, Robert A.; Baumgarten, Keith M.; Carey, James L.; DeBerardino, Thomas M.; Hame, Sharon L.; Hannafin, Jo A.; Miller, Bruce S.; Nissen, Carl W.; Taft, Timothy N.; Wolf, Brian R.; Wright, Rick W.

    2015-01-01

    Background ACL reconstruction failure occurs in up to 10% of cases. Technical errors are considered the most common cause of graft failure despite the absence of validated studies. There is limited data regarding the agreement among orthopedic surgeons in terms of the etiology of primary ACL reconstruction failure and accuracy of graft tunnel placement. Purpose The purpose of this study is to test the hypothesis that experienced knee surgeons have a high level of inter-observer reliability in the agreement of the etiology of the primary ACL reconstruction failure, anatomical graft characteristics, tunnel placement. Methods Twenty cases of revision ACL reconstruction were randomly selected from the MARS database. Each case included the patient's history, standardized radiographs, and a concise 30-second arthroscopic video taken at the time of revision demonstrating the graft remnant and location of the tunnel apertures. 10 MARS surgeons not involved with the primary surgery reviewed all 20 cases. Each surgeon completed a two-part questionnaire dealing with each surgeon's training and practice as well as the placement of the femoral and tibial tunnels, condition of the primary graft, and the surgeon's opinion as to the etiology of graft failure. Inter-rater agreement was determined for each question. Inter-rater agreement was determined for each question with the kappa coefficient and prevalence adjusted bias adjusted kappa (PABAK). Results The 10 reviewers were in practice an average of 14 years. All performed at least 25 ACL reconstructions per year and 9 were fellowship-trained in sports medicine. There was wide variability in agreement among knee experts as to the specific etiology of ACL graft failure. When specifically asked about technical error as the cause for failure, inter-observer agreement was only slight (prevalence adjusted bias adjusted kappa [PABAK]: 0.26). There was fair overall agreement on ideal femoral tunnel placement (PABAK: 0.55), but only

  4. Acute kidney failure

    MedlinePlus

    Kidney failure; Renal failure; Renal failure - acute; ARF; Kidney injury - acute ... There are many possible causes of kidney damage. They include: ... cholesterol (cholesterol emboli) Decreased blood flow due to very ...

  5. What Is Heart Failure?

    MedlinePlus

    ... page from the NHLBI on Twitter. What Is Heart Failure? Heart failure is a condition in which the heart can' ... force. Some people have both problems. The term "heart failure" doesn't mean that your heart has stopped ...

  6. Heart failure - medicines

    MedlinePlus

    CHF - medicines; Congestive heart failure - medicines; Cardiomyopathy - medicines; HF - medicines ... You will need to take most of your heart failure medicines every day. Some medicines are taken ...

  7. Phase diagrams of bosonic ABn chains

    NASA Astrophysics Data System (ADS)

    Cruz, G. J.; Franco, R.; Silva-Valencia, J.

    2016-04-01

    The A B N - 1 chain is a system that consists of repeating a unit cell with N sites where between the A and B sites there is an energy difference of λ. We considered bosons in these special lattices and took into account the kinetic energy, the local two-body interaction, and the inhomogenous local energy in the Hamiltonian. We found the charge density wave (CDW) and superfluid and Mott insulator phases, and constructed the phase diagram for N = 2 and 3 at the thermodynamic limit. The system exhibited insulator phases for densities ρ = α/ N, with α being an integer. We obtained that superfluid regions separate the insulator phases for densities larger than one. For any N value, we found that for integer densities ρ, the system exhibits ρ + 1 insulator phases, a Mott insulator phase, and ρ CDW phases. For non-integer densities larger than one, several CDW phases appear.

  8. Reentrant Phase Diagram of Network Fluids

    NASA Astrophysics Data System (ADS)

    Russo, J.; Tavares, J. M.; Teixeira, P. I. C.; Telo da Gama, M. M.; Sciortino, F.

    2011-02-01

    We introduce a microscopic model for particles with dissimilar patches which displays an unconventional “pinched” phase diagram, similar to the one predicted by Tlusty and Safran in the context of dipolar fluids [Science 290, 1328 (2000)SCIEAS0036-807510.1126/science.290.5495.1328]. The model—based on two types of patch interactions, which account, respectively, for chaining and branching of the self-assembled networks—is studied both numerically via Monte Carlo simulations and theoretically via first-order perturbation theory. The dense phase is rich in junctions, while the less-dense phase is rich in chain ends. The model provides a reference system for a deep understanding of the competition between condensation and self-assembly into equilibrium-polymer chains.

  9. Phase diagram of water in carbon nanotubes.

    PubMed

    Takaiwa, Daisuke; Hatano, Itaru; Koga, Kenichiro; Tanaka, Hideki

    2008-01-08

    A phase diagram of water in single-walled carbon nanotubes at atmospheric pressure is proposed, which summarizes ice structures and their melting points as a function of the tube diameter up to 1.7 nm. The investigation is based on extensive molecular dynamics simulations over numerous thermodynamic states on the temperature-diameter plane. Spontaneous freezing of water in the simulations and the analysis of ice structures at 0 K suggest that there exist at least nine ice phases in the cylindrical space, including those reported by x-ray diffraction studies and those unreported by simulation or experiment. Each ice has a structure that maximizes the number of hydrogen bonds under the cylindrical confinement. The results show that the melting curve has many local maxima, each corresponding to the highest melting point for each ice form. The global maximum in the melting curve is located at approximately 11 A, where water freezes in a square ice nanotube.

  10. Specification of Learning Content Using Feature Diagrams

    NASA Astrophysics Data System (ADS)

    Damaševičius, Robertas

    The main idea of a learning object (LO) is to break educational content down into small chunks that can be reused in various learning environments. When reused, such small chunks of educational content are combined in various ways leading to a great variability of the learning content. We propose using feature diagrams (FDs) for the specification of learning content at different layers of abstraction starting from the organization of teaching material in a lecture down to the specification and demonstration of particular software/hardware components. FDs can be used by (1) designers, teachers, and learners for graphical representation of domain knowledge in LOs; (2) programmers to specify and express variability-commonality relationships of LOs at a higher abstraction level to allow the development and implementation of generative LOs; and (3) researchers as a vehicle for analysis and better understanding of the e-Learning domain itself.

  11. Geostrophic Scatter Diagrams and Potential Vorticity Dynamics.

    NASA Astrophysics Data System (ADS)

    Read, P. L.; Rhines, P. B.; White, A. A.

    1986-12-01

    where S is the potential vorticity forcing, K the lateral eddy (or viscous) v the horizontal velocity, and the integrals are taken over and around any region enclosed by a mean streamline. Hence dQ/dis often negative. corresponding to two common properties of quasi-geostrophic circulations: that the eddy motion (or viscosity) transport Q down its mean gradient (K > 0) and that the circulation integral have the same sign as the potential vorticity forcing. Two sets of examples, both involving (Q,) scatter diagrams constructed from numerically simulated data, are presented. One relates to steady baroclinic wave motion in a rotating annulus system, and the other to the time-averaged circulation in an ocean basin.

  12. The wiring diagram for plant G signaling

    SciTech Connect

    Colaneri, Alejandro C.; Jones, Alan M.

    2014-10-01

    Like electronic circuits, the modular arrangement of cell-signaling networks decides how inputs produce outputs. Animal heterotrimeric guanine nucleotide binding proteins (G-proteins) operate as switches in the circuits that signal between extracellular agonists and intracellular effectors. There still is no biochemical evidence for a receptor or its agonist in the plant G-protein pathways. Plant G-proteins deviate in many important ways from the animal paradigm. This paper covers important discoveries from the last two years that enlighten these differences and ends describing alternative wiring diagrams for the plant signaling circuits regulated by G-proteins. Finally, we propose that plant G-proteins are integrated in the signaling circuits as variable resistor rather than switches, controlling the flux of information in response to the cell's metabolic state.

  13. The wiring diagram for plant G signaling

    DOE PAGES

    Colaneri, Alejandro C.; Jones, Alan M.

    2014-10-01

    Like electronic circuits, the modular arrangement of cell-signaling networks decides how inputs produce outputs. Animal heterotrimeric guanine nucleotide binding proteins (G-proteins) operate as switches in the circuits that signal between extracellular agonists and intracellular effectors. There still is no biochemical evidence for a receptor or its agonist in the plant G-protein pathways. Plant G-proteins deviate in many important ways from the animal paradigm. This paper covers important discoveries from the last two years that enlighten these differences and ends describing alternative wiring diagrams for the plant signaling circuits regulated by G-proteins. Finally, we propose that plant G-proteins are integrated inmore » the signaling circuits as variable resistor rather than switches, controlling the flux of information in response to the cell's metabolic state.« less

  14. Phase diagram of chirally imbalanced QCD matter

    SciTech Connect

    Chernodub, M. N.; Nedelin, A. S.

    2011-05-15

    We compute the QCD phase diagram in the plane of the chiral chemical potential and temperature using the linear sigma model coupled to quarks and to the Polyakov loop. The chiral chemical potential accounts for effects of imbalanced chirality due to QCD sphaleron transitions which may emerge in heavy-ion collisions. We found three effects caused by the chiral chemical potential: the imbalanced chirality (i) tightens the link between deconfinement and chiral phase transitions; (ii) lowers the common critical temperature; (iii) strengthens the order of the phase transition by converting the crossover into the strong first order phase transition passing via the second order end point. Since the fermionic determinant with the chiral chemical potential has no sign problem, the chirally imbalanced QCD matter can be studied in numerical lattice simulations.

  15. Understanding starch gelatinization: The phase diagram approach.

    PubMed

    Carlstedt, Jonas; Wojtasz, Joanna; Fyhr, Peter; Kocherbitov, Vitaly

    2015-09-20

    By constructing a detailed phase diagram for the potato starch-water system based on data from optical microscopy, synchrotron X-ray scattering and differential scanning calorimetry, we show that gelatinization can be interpreted in analogy with a eutectic transition. The phase rule explains why the temperature of the gelatinization transition (G) is independent on water content. Furthermore, the melting (M1) endotherm observed in DSC represents a liquidus line; the temperature for this event increases with increasing starch concentration. Both the lamellar spacing and the inter-helix distance were observed to decrease with increasing starch content for starch concentrations between approximately 65 wt% and 75 wt%, while the inter-helix distance continued decreasing upon further dehydration. Understanding starch gelatinization has been a longstanding challenge. The novel approach presented here shows interpretation of this phenomenon from a phase equilibria perspective.

  16. Microfluidic Evaporation for Phase Diagram Screening

    NASA Astrophysics Data System (ADS)

    Moreau, Patrick; Salmon, Jean-Baptiste; Leng, Jacques

    2007-11-01

    We use a pervaporation-based microfluidic device to concentrate solutions in a controlled way. This allows us to develop chips for phase diagram screening,and to study both fundamental and technological issues, such as the impact of kinetic pathway of concentration on a variety of aqueous solutions (colloids, surfactants, polymers and mixtures of thereof). The first part of the presentation will deals with the characterization of the concentration process (including analytical results, numerical simulations, and experimental observations). It will be shown that our device is well suited for a wide range of particle sizes in the colloidal range. In the second part, we will present results obtained on several systems during (along) the concentration process (surfactants and polymers). On-chip FRAP (fluorescence recovery after photobleaching) and microrheology measurements will be presented in addition to optical and fluorescence microscopy.

  17. Expression of Superparamagnetic Particles on FORC Diagrams

    NASA Astrophysics Data System (ADS)

    Hirt, A. M.; Kumari, M.; Crippa, F.; Petri-Fink, A.

    2015-12-01

    Identification of superparamagnetic (SP) particles in natural materials provides information on processes that lead to the new formation or dissolution of iron oxides. SP particles express themselves on first-order reversal curve (FORC) diagrams as a distribution centered near the origin of the diagram. Pike et al. (2001, GJI, 145, 721) demonstrated that thermal relaxation produces an upward shift in the FORC distribution, and attributed this to a pause encountered at each reversal field. In this study we examine the relationship between this upward shift and particles size on two sets of synthetic iron oxide nanoparticles. One set of coated magnetite particles have well-constrained particles size with 9, 16 and 20 nm as their diameter. A second set from the FeraSpin™ Series, consisting of FeraSpinXS, M and XL, were evaluated. Rock magnetic experiments indicate that the first set of samples is exclusively magnetite, whereas the FeraSpin samples contain predominantly magnetite with some degree of oxidation. Samples from both sets show that the upward shift of the FORC distribution at the origin increases with decreasing particle size. The amount of shift in the FeraSpin series is less when compared to the samples from the first set. This is attributed to the effect of interaction that counteracts the effect of thermal relaxation behavior of the SP particles. The FeraSpin series also shows a broader FORC distribution on the vertical axis that appears to be related to non-saturation of the hysteresis curve at maximum applied field. This non-saturation behavior can be due to spins of very fine particles or oxidation to hematite. AC susceptibility at low temperature indicates that particle interaction may affect the effective magnetic particle size. Our results suggest that the FORC distribution in pure SP particle systems provides information on the particle size distribution or oxidation, which can be further evaluated with low temperature techniques.

  18. Time-temperature-transformation diagrams with more than one nose

    NASA Technical Reports Server (NTRS)

    Weinberg, Michael C.

    1992-01-01

    The structures of time-temperature-transformation diagrams of glasses which crystallize the combined homogeneous and heterogeneous crystallization mechanisms are examined. Considerations are given to the factors which might produce more than one extremum in such diagrams. Specific nucleation and growth models are used, and the influence of the parameters which appear in the nucleation and growth rate expressions upon the structure of the diagrams is evaluated.

  19. 55. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT FLOW DIAGRAM, REPRESENTING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    55. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT FLOW DIAGRAM, REPRESENTING ONE COMPLETE CYCLE - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  20. 53. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT FLOW DIAGRAM, REPRESENTING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    53. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT FLOW DIAGRAM, REPRESENTING ONE COMPLETE CYCLE - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  1. 54. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT FLOW DIAGRAM, REPRESENTING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    54. PHOTOCOPY OF DRAWING AMMONIA LEACHING PLANT FLOW DIAGRAM, REPRESENTING ONE COMPLETE CYCLE - Kennecott Copper Corporation, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

  2. Massive basketball diagram for a thermal scalar field theory

    SciTech Connect

    Andersen, Jens O.; Braaten, Eric; Strickland, Michael

    2000-08-15

    The ''basketball diagram'' is a three-loop vacuum diagram for a scalar field theory that cannot be expressed in terms of one-loop diagrams. We calculate this diagram for a massive scalar field at nonzero temperature, reducing it to expressions involving three-dimensional integrals that can be easily evaluated numerically. We use this result to calculate the free energy for a massive scalar field with a {phi}{sup 4} interaction to three-loop order. (c) 2000 The American Physical Society.

  3. A Picture Is Worth a Thousand Connections: The Facilitative Effects of Diagrams on Mental Model Development and Task Performance.

    ERIC Educational Resources Information Center

    Fiore, Stephen M.; Cuevas, Haydee M.; Oser, Randall L.

    2003-01-01

    Describes a study of undergraduates that investigated the influence of training format on knowledge structure development and how differing knowledge structure measurement techniques can be used to best assess training effectiveness. Manipulated the presence of diagrams in a computer-based training tutorial to assess mental model development and…

  4. Component failure data handbook

    SciTech Connect

    Gentillon, C.D.

    1991-04-01

    This report presents generic component failure rates that are used in reliability and risk studies of commercial nuclear power plants. The rates are computed using plant-specific data from published probabilistic risk assessments supplemented by selected other sources. Each data source is described. For rates with four or more separate estimates among the sources, plots show the data that are combined. The method for combining data from different sources is presented. The resulting aggregated rates are listed with upper bounds that reflect the variability observed in each rate across the nuclear power plant industry. Thus, the rates are generic. Both per hour and per demand rates are included. They may be used for screening in risk assessments or for forming distributions to be updated with plant-specific data.

  5. Oak Ridge K-25 Site Technology Logic Diagram. Volume 2, Technology Logic Diagrams

    SciTech Connect

    Fellows, R.L.

    1993-02-26

    The Oak Ridge K-25 Technology Logic Diagram (TLD), a decision support tool for the K-25 Site, was developed to provide a planning document that relates envirorunental restoration and waste management problems at the Oak Ridge K-25 Site to potential technologies that can remediate these problems. The TLD technique identifies the research necessary to develop these technologies to a state that allows for technology transfer and application to waste management, remedial action, and decontamination and decommissioning activities. The TLD consists of four separate volumes-Vol. 1, Vol. 2, Vol. 3A, and Vol. 3B. Volume 1 provides introductory and overview information about the TLD. This volume, Volume 2, contains logic diagrams with an index. Volume 3 has been divided into two separate volumes to facilitate handling and use.

  6. Progressive Failure Analysis Methodology for Laminated Composite Structures

    NASA Technical Reports Server (NTRS)

    Sleight, David W.

    1999-01-01

    A progressive failure analysis method has been developed for predicting the failure of laminated composite structures under geometrically nonlinear deformations. The progressive failure analysis uses C(exp 1) shell elements based on classical lamination theory to calculate the in-plane stresses. Several failure criteria, including the maximum strain criterion, Hashin's criterion, and Christensen's criterion, are used to predict the failure mechanisms and several options are available to degrade the material properties after failures. The progressive failure analysis method is implemented in the COMET finite element analysis code and can predict the damage and response of laminated composite structures from initial loading to final failure. The different failure criteria and material degradation methods are compared and assessed by performing analyses of several laminated composite structures. Results from the progressive failure method indicate good correlation with the existing test data except in structural applications where interlaminar stresses are important which may cause failure mechanisms such as debonding or delaminations.

  7. Enantiomeric 3-chloromandelic acid system: binary melting point phase diagram, ternary solubility phase diagrams and polymorphism.

    PubMed

    Le Minh, Tam; von Langermann, Jan; Lorenz, Heike; Seidel-Morgenstern, Andreas

    2010-09-01

    A systematic study of binary melting point and ternary solubility phase diagrams of the enantiomeric 3-chloromandelic acid (3-ClMA) system was performed under consideration of polymorphism. The melting point phase diagram was measured by means of thermal analysis, that is, using heat-flux differential scanning calorimetry (DSC). The results reveal that 3-ClMA belongs to the racemic compound-forming systems. Polymorphism was found for both the enantiomer and the racemate as confirmed by X-ray powder diffraction analysis. The ternary solubility phase diagram of 3-ClMA in water was determined between 5 and 50 degrees C by the classical isothermal technique. The solubilities of the pure enantiomers are extremely temperature-dependent. The solid-liquid equilibria of racemic 3-ClMA are not trivial due to the existence of polymorphism. The eutectic composition in the chiral system changes as a function of temperature. Further, solubility data in the alternative solvent toluene are also presented.

  8. Advanced Heart Failure

    MedlinePlus

    ... Artery Disease Venous Thromboembolism Aortic Aneurysm More Advanced Heart Failure Updated:Feb 9,2017 When heart failure (HF) ... content was last reviewed on 04/06/2015. Heart Failure • Home • About Heart Failure • Causes and Risks for ...

  9. [Heart failure, a disease of the elderly].

    PubMed

    Hanon, Olivier

    2004-09-25

    INCREASING PREVALENCE OF HOSPITALISATIONS AND MORTALITY: Heart failure represents a major public health problem. Indeed, the ageing of the population and the frequency of cardiovascular risk factors explain the considerable increase in the prevalence of heart failure over the past few years. SYSTOLIC FUNCTION IS USUALLY PRESERVED: The physiopathological features of cardiovascular ageing have resulted in the high prevalence of heart failure with preserved systolic function. Hence, in patients aged over 75 presenting with heart failure, around 50% exhibit preserved ejection fraction. THE NEED FOR GERONTOLOGICAL ASSESSMENT: The prognosis of heart failure remains severe, notably in elderly, fragile patients often exhibiting several diseases. Within this context, a gerontological assessment is crucial in order to screen for concomitant diseases, the degree of the patients' dependence and the presence of "fragility". This work-up must assess the cognitive function, autonomy, somatic status, living conditions and the medico-social management of these patients.

  10. The Failure Analysis in Traction Power System

    NASA Astrophysics Data System (ADS)

    Kim, Hyungchul; Heo, Guk-bum; Lee, Hyungwoo; Kim, Dong Jin; Kim, Jin O.

    2008-10-01

    This paper presents a failure analysis of traction power systems. The electric railway consists of traction power systems, various vehicles, operating equipment, track, overhead line and electric equipment. It is a fundamental function of traction power systems that they supply customers with acceptable reliability and high quality power. Perhaps the most commonly used reliability assessment for railway systems has been the failure analysis of the traction signal system. The reliability assessment of traction power systems has also been an indispensable issue for reliability assessment. This paper deals with the classification of railway accidents caused by electrification problems, the estimation of failure rate in power equipments and failure analysis using fault trees. In study cases, the fault tree method for failure analysis is applied to railway substations in South Korea.

  11. Improving Students' Diagram Comprehension with Classroom Instruction

    ERIC Educational Resources Information Center

    Cromley, Jennifer G.; Perez, Tony C.; Fitzhugh, Shannon L.; Newcombe, Nora S.; Wills, Theodore W.; Tanaka, Jacqueline C.

    2013-01-01

    The authors tested whether students can be taught to better understand conventional representations in diagrams, photographs, and other visual representations in science textbooks. The authors developed a teacher-delivered, workbook-and-discussion-based classroom instructional method called Conventions of Diagrams (COD). The authors trained 1…

  12. Persistence Diagrams of High-Resolution Temporal Rainfall

    NASA Astrophysics Data System (ADS)

    Fernández Méndez, F.; Carsteanu, A. A.

    2015-12-01

    This study applies Topological Data Analysis (TDA), by generating persistence diagrams to uncover patterns in the data of high-resolution temporal rainfall intensities from Iowa City (IIHR, U of Iowa). Persistence diagrams are a way to identify essential cycles in state-space representations of the data.

  13. Heuristic Diagrams as a Tool to Teach History of Science

    ERIC Educational Resources Information Center

    Chamizo, Jose A.

    2012-01-01

    The graphic organizer called here heuristic diagram as an improvement of Gowin's Vee heuristic is proposed as a tool to teach history of science. Heuristic diagrams have the purpose of helping students (or teachers, or researchers) to understand their own research considering that asks and problem-solving are central to scientific activity. The…

  14. Drawing Euler Diagrams with Circles: The Theory of Piercings.

    PubMed

    Stapleton, Gem; Leishi Zhang; Howse, John; Rodgers, Peter

    2011-07-01

    Euler diagrams are effective tools for visualizing set intersections. They have a large number of application areas ranging from statistical data analysis to software engineering. However, the automated generation of Euler diagrams has never been easy: given an abstract description of a required Euler diagram, it is computationally expensive to generate the diagram. Moreover, the generated diagrams represent sets by polygons, sometimes with quite irregular shapes that make the diagrams less comprehensible. In this paper, we address these two issues by developing the theory of piercings, where we define single piercing curves and double piercing curves. We prove that if a diagram can be built inductively by successively adding piercing curves under certain constraints, then it can be drawn with circles, which are more esthetically pleasing than arbitrary polygons. The theory of piercings is developed at the abstract level. In addition, we present a Java implementation that, given an inductively pierced abstract description, generates an Euler diagram consisting only of circles within polynomial time.

  15. Diagram This Headline in One Minute, if You Can

    ERIC Educational Resources Information Center

    Landecker, Heidi

    2009-01-01

    Say "sentence diagramming" to people of a certain age, and one gets different reactions. Say it to most college students, and one gets a blank look. But not from the 24 students in Lucy Ferriss's "Constructing Thought," a half-credit course in the English department at Trinity College. They know how to diagram a sentence--and…

  16. 30 CFR 556.8 - Leasing maps and diagrams.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Leasing maps and diagrams. 556.8 Section 556.8... Management, General § 556.8 Leasing maps and diagrams. (a) Any area of the OCS which has been appropriately... operation under section 12(d) of the Act. (b) BOEM shall prepare leasing maps and official...

  17. 30 CFR 556.8 - Leasing maps and diagrams.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Leasing maps and diagrams. 556.8 Section 556.8... Management, General § 556.8 Leasing maps and diagrams. (a) Any area of the OCS which has been appropriately... operation under section 12(d) of the Act. (b) BOEM shall prepare leasing maps and official...

  18. 30 CFR 556.8 - Leasing maps and diagrams.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false Leasing maps and diagrams. 556.8 Section 556.8... Management, General § 556.8 Leasing maps and diagrams. (a) Any area of the OCS which has been appropriately... operation under section 12(d) of the Act. (b) BOEM shall prepare leasing maps and official...

  19. Diversions: Spatial Thinking Tasks--Cube Diagrams and Drawings

    ERIC Educational Resources Information Center

    Gough, John

    2009-01-01

    This article illustrates spatial thinking tasks through cube diagrams and drawings. The author talks about the pentacube diagram that is based on the principle that a vertical cube-edge is shown "vertically". The author describes how to extend isometric drawing to include triangular wedges that are made by slicing single cubes, bi-cubes,…

  20. Quark diagrams and the. cap omega. /sup -/ nonleptonic decays

    SciTech Connect

    Ponce, W.A.

    1980-09-01

    The quark-diagram model for nonleptonic two-body baryon decays is discussed and applied to the decay of the ..cap omega../sup -/ particle. Current algebra is not employed, but the relation between the quark diagrams and current algebra is explored.

  1. An Introductory Idea for Teaching Two-Component Phase Diagrams

    ERIC Educational Resources Information Center

    Peckham, Gavin D.; McNaught, Ian J.

    2011-01-01

    The teaching of two-component phase diagrams has attracted little attention in this "Journal," and it is hoped that this article will make a useful contribution. Current physical chemistry textbooks describe two-component phase diagrams adequately, but do so in a piecemeal fashion one section at a time; first solid-liquid equilibria, then…

  2. Using a Spreadsheet To Explore Melting, Dissolving and Phase Diagrams.

    ERIC Educational Resources Information Center

    Goodwin, Alan

    2002-01-01

    Compares phase diagrams relating to the solubilities and melting points of various substances in textbooks with those generated by a spreadsheet using data from the literature. Argues that differences between the diagrams give rise to new chemical insights. (Author/MM)

  3. Adding Value to Force Diagrams: Representing Relative Force Magnitudes

    ERIC Educational Resources Information Center

    Wendel, Paul

    2011-01-01

    Nearly all physics instructors recognize the instructional value of force diagrams, and this journal has published several collections of exercises to improve student skill in this area. Yet some instructors worry that too few students perceive the conceptual and problem-solving utility of force diagrams, and over recent years a rich variety of…

  4. Pourbaix ("E"-pH-M) Diagrams in Three Dimensions

    ERIC Educational Resources Information Center

    Pesterfield, Lester L.; Maddox, Jeremy B.; Crocker, Michael S.; Schweitzer, George K.

    2012-01-01

    "E"-pH (Pourbaix) diagrams provide an important graphical link between the thermodynamic calculations of potential, pH, equilibrium constant, concentration, and changes in Gibbs energy and the experimentally observed behavior of species in aqueous solutions. The utility of "E"-pH diagrams is extended with the introduction of an additional…

  5. Water, Water Everywhere: Phase Diagrams of Ordinary Water Substance

    ERIC Educational Resources Information Center

    Glasser, L.

    2004-01-01

    The full phase diagram of water in the form of a graphical representation of the three-dimensional (3D) PVT diagram using authentic data is presented. An interesting controversy regarding the phase behavior of water was the much-touted proposal of a solid phase of water, polywater, supposedly stable under atmospheric conditions.

  6. Application of quaternary phase diagrams to compound semiconductor processing

    SciTech Connect

    Sinclair, R.

    1994-10-01

    Isobaric, isothermal phase diagrams are a molar representation of condensed phases in equilibrium with each other at a fixed temperature, pressure, and composition. Since three or four elements are usually involved at a fabricated interface in a semiconductor device, knowledge of the appropriate ternary or quaternary phase diagram is important for optimizing the processing parameters and designing long term stability of devices. While the use of phase diagrams is well-established in the fields of metallurgy, ceramics and mineralogy, only recently have phase diagrams been employed to provide a framework for understanding thin film reactions on a substrate, encountered in semiconductor processing. Even though there are many examples of applications of ternary phase diagrams in the semiconductor literature (for instance, metallization of GaAs, the use of refractory metal silicides for metallization layers in VLSI devices and oxidation of III-V compounds), the same is not true for quaternary phase diagrams. To date, the only application is oxidation of mercury cadmium telluride. This lack of examples is not warranted, as four elements are often involved at a critical interface in compound semiconductor processing and devices. This paper reports on the progress made to remedy this situation by considering the application of quaternary phase diagrams to understanding and predicting the behavior of II-VI thin film interfaces in photovoltaic devices under annealing conditions. Moreover, for the first time, solid solubility is taken into account for quaternary phase diagrams of semiconductor systems.

  7. Diagram, Gesture, Agency: Theorizing Embodiment in the Mathematics Classroom

    ERIC Educational Resources Information Center

    de Freitas, Elizabeth; Sinclair, Nathalie

    2012-01-01

    In this paper, we use the work of philosopher Gilles Chatelet to rethink the gesture/diagram relationship and to explore the ways mathematical agency is constituted through it. We argue for a fundamental philosophical shift to better conceptualize the relationship between gesture and diagram, and suggest that such an approach might open up new…

  8. The Effect of Causal Diagrams on Text Learning

    ERIC Educational Resources Information Center

    McCrudden, Matthew T.; Schraw, Gregory; Lehman, Stephen; Poliquin, Anne

    2007-01-01

    We examined the effect of studying a causal diagram on comprehension of causal relationships from an expository science text. A causal diagram is a type of visual display that explicitly represents cause-effect relationships. In Experiment 1, readers between conditions did not differ with respect to memory for main ideas, but the readers who…

  9. Phase diagram for inertial granular flows

    NASA Astrophysics Data System (ADS)

    DeGiuli, E.; McElwaine, J. N.; Wyart, M.

    2016-07-01

    Flows of hard granular materials depend strongly on the interparticle friction coefficient μp and on the inertial number I , which characterizes proximity to the jamming transition where flow stops. Guided by numerical simulations, we derive the phase diagram of dense inertial flow of spherical particles, finding three regimes for 10-4≲I ≲10-1 : frictionless, frictional sliding, and rolling. These are distinguished by the dominant means of energy dissipation, changing from collisional to sliding friction, and back to collisional, as μp increases from zero at constant I . The three regimes differ in their kinetics and rheology; in particular, the velocity fluctuations and the stress ratio both display nonmonotonic behavior with μp, corresponding to transitions between the three regimes of flow. We rationalize the phase boundaries between these regimes, show that energy balance yields scaling relations between microscopic properties in each of them, and derive the strain scale at which particles lose memory of their velocity. For the frictional sliding regime most relevant experimentally, we find for I ≥10-2.5 that the growth of the macroscopic friction μ (I ) with I is induced by an increase of collisional dissipation. This implies in that range that μ (I ) -μ (0 ) ˜I1 -2 b , where b ≈0.2 is an exponent that characterizes both the dimensionless velocity fluctuations L ˜I-b and the density of sliding contacts χ ˜Ib .

  10. Diagram of Cell to Cell Communication

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  11. Community detection by graph Voronoi diagrams

    NASA Astrophysics Data System (ADS)

    Deritei, Dávid; Lázár, Zsolt I.; Papp, István; Járai-Szabó, Ferenc; Sumi, Róbert; Varga, Levente; Ravasz Regan, Erzsébet; Ercsey-Ravasz, Mária

    2014-06-01

    Accurate and efficient community detection in networks is a key challenge for complex network theory and its applications. The problem is analogous to cluster analysis in data mining, a field rich in metric space-based methods. Common to these methods is a geometric, distance-based definition of clusters or communities. Here we propose a new geometric approach to graph community detection based on graph Voronoi diagrams. Our method serves as proof of principle that the definition of appropriate distance metrics on graphs can bring a rich set of metric space-based clustering methods to network science. We employ a simple edge metric that reflects the intra- or inter-community character of edges, and a graph density-based rule to identify seed nodes of Voronoi cells. Our algorithm outperforms most network community detection methods applicable to large networks on benchmark as well as real-world networks. In addition to offering a computationally efficient alternative for community detection, our method opens new avenues for adapting a wide range of data mining algorithms to complex networks from the class of centroid- and density-based clustering methods.

  12. Steam generator tube failures

    SciTech Connect

    MacDonald, P.E.; Shah, V.N.; Ward, L.W.; Ellison, P.G.

    1996-04-01

    A review and summary of the available information on steam generator tubing failures and the impact of these failures on plant safety is presented. The following topics are covered: pressurized water reactor (PWR), Canadian deuterium uranium (CANDU) reactor, and Russian water moderated, water cooled energy reactor (VVER) steam generator degradation, PWR steam generator tube ruptures, the thermal-hydraulic response of a PWR plant with a faulted steam generator, the risk significance of steam generator tube rupture accidents, tubing inspection requirements and fitness-for-service criteria in various countries, and defect detection reliability and sizing accuracy. A significant number of steam generator tubes are defective and are removed from service or repaired each year. This wide spread damage has been caused by many diverse degradation mechanisms, some of which are difficult to detect and predict. In addition, spontaneous tube ruptures have occurred at the rate of about one every 2 years over the last 20 years, and incipient tube ruptures (tube failures usually identified with leak detection monitors just before rupture) have been occurring at the rate of about one per year. These ruptures have caused complex plant transients which have not always been easy for the reactor operators to control. Our analysis shows that if more than 15 tubes rupture during a main steam line break, the system response could lead to core melting. Although spontaneous and induced steam generator tube ruptures are small contributors to the total core damage frequency calculated in probabilistic risk assessments, they are risk significant because the radionuclides are likely to bypass the reactor containment building. The frequency of steam generator tube ruptures can be significantly reduced through appropriate and timely inspections and repairs or removal from service.

  13. VennMaster: Area-proportional Euler diagrams for functional GO analysis of microarrays

    PubMed Central

    Kestler, Hans A; Müller, André; Kraus, Johann M; Buchholz, Malte; Gress, Thomas M; Liu, Hongfang; Kane, David W; Zeeberg, Barry R; Weinstein, John N

    2008-01-01

    Background Microarray experiments generate vast amounts of data. The functional context of differentially expressed genes can be assessed by querying the Gene Ontology (GO) database via GoMiner. Directed acyclic graph representations, which are used to depict GO categories enriched with differentially expressed genes, are difficult to interpret and, depending on the particular analysis, may not be well suited for formulating new hypotheses. Additional graphical methods are therefore needed to augment the GO graphical representation. Results We present an alternative visualization approach, area-proportional Euler diagrams, showing set relationships with semi-quantitative size information in a single diagram to support biological hypothesis formulation. The cardinalities of sets and intersection sets are represented by area-proportional Euler diagrams and their corresponding graphical (circular or polygonal) intersection areas. Optimally proportional representations are obtained using swarm and evolutionary optimization algorithms. Conclusion VennMaster's area-proportional Euler diagrams effectively structure and visualize the results of a GO analysis by indicating to what extent flagged genes are shared by different categories. In addition to reducing the complexity of the output, the visualizations facilitate generation of novel hypotheses from the analysis of seemingly unrelated categories that share differentially expressed genes. PMID:18230172

  14. Improving high school physical science students' understanding of the electromagnetic spectrum: A modified diagram approach

    NASA Astrophysics Data System (ADS)

    Quebedeaux, James Edward

    The focus of this study was to identify major conceptual difficulties that selected public high school physical science students encounter in understanding a standard electromagnetic spectrum diagram. A research-driven, modified version of that standard diagram was used in this study to determine the value added to student understanding of electromagnetic waves. A content analysis was performed on electromagnetic spectrum diagrams found in US textbooks from the 1950s through the present. A class of public high school physical science students participated in a study consisting of four activities conducted during a three-week unit. Students were given a pre- and post-achievement test and a pre- and post-survey on the regions of the electromagnetic spectrum. At the conclusion of each activity, selected students were interviewed and each co-constructed a concept map with the researcher. The Electromagnetic Spectrum Literacy Rubric (ESLR) was designed and used to assess students' conceptual understanding periodically as they proceeded through the unit study. A mixed methods analysis was performed, employing both qualitative and quantitative data. A paired t-test determined that there was a statistically significant difference (p = 0.014) between the pre- and post-achievement test scores for the class of students participating in the unit study. Effect sizes also determined that students have difficulties with mathematical calculations and wave properties. These topics present conceptual challenges which must be overcome to understand and use an electromagnetic spectrum diagram effectively.

  15. The coupling of thermochemistry and phase diagrams for group III-V semiconductor systems. Final report

    SciTech Connect

    Anderson, T.J.

    1998-07-21

    The project was directed at linking the thermochemical properties of III-V compound semiconductors systems with the reported phase diagrams. The solid-liquid phase equilibrium problem was formulated and three approaches to calculating the reduced standard state chemical potential were identified and values were calculated. In addition, thermochemical values for critical properties were measured using solid state electrochemical techniques. These values, along with the standard state chemical potentials and other available thermochemical and phase diagram data, were combined with a critical assessment of selected III-V systems. This work was culminated with a comprehensive assessment of all the III-V binary systems. A novel aspect of the experimental part of this project was the demonstration of the use of a liquid encapsulate to measure component activities by a solid state emf technique in liquid III-V systems that exhibit high vapor pressures at the measurement temperature.

  16. Calculation of Gallium-metal-Arsenic phase diagrams

    NASA Technical Reports Server (NTRS)

    Scofield, J. D.; Davison, J. E.; Ray, A. E.; Smith, S. R.

    1991-01-01

    Electrical contacts and metallization to GaAs solar cells must survive at high temperatures for several minutes under specific mission scenarios. The determination of which metallizations or alloy systems that are able to withstand extreme thermal excursions with minimum degradation to solar cell performance can be predicted by properly calculated temperature constitution phase diagrams. A method for calculating a ternary diagram and its three constituent binary phase diagrams is briefly outlined and ternary phase diagrams for three Ga-As-X alloy systems are presented. Free energy functions of the liquid and solid phase are approximated by the regular solution theory. Phase diagrams calculated using this method are presented for the Ga-As-Ge and Ga-As-Ag systems.

  17. Drug user treatment failure blindness?

    PubMed

    Einstein, Stan

    2012-01-01

    An ethnographic case study of a "failed" single goal (abstinence) based individual and group therapy treatment of a New York City, Harlem-based, single, young-adult of color, IDU, mother, which ended in "death by overdose," after a period of abstinence, is presented almost 50 years later, in which complex, multidimensional structural barriers, "normed," consensualized, ideologically-driven preconceptions and an array of contextual, situational and relevant stakeholder factors, which may have resulted in intervention "failure blindness," are reviewed. The need to introduce failure analysis, blindness and management, as well as success analysis, blindness and management, as integral parts of treatment planning, implementation and assessment is raised.

  18. Field failure mechanisms for photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Dumas, L. N.; Shumka, A.

    1981-01-01

    Beginning in 1976, Department of Energy field centers have installed and monitored a number of field tests and application experiments using current state-of-the-art photovoltaic modules. On-site observations of module physical and electrical degradation, together with in-depth laboratory analysis of failed modules, permits an overall assessment of the nature and causes of early field failures. Data on failure rates are presented, and key failure mechanisms are analyzed with respect to origin, effect, and prospects for correction. It is concluded that all failure modes identified to date are avoidable or controllable through sound design and production practices.

  19. The ruthenium-yttrium system: An experimental calorimetric study with a phase diagram optimization

    SciTech Connect

    Selhaoui, N.; Bouirden, L.; Charles, J.; Gachon, J.C.; Kleppa, O.J.

    1998-07-01

    After an experimental determination of the standard enthalpies of formation of Ru{sub 0.67}Y{sub 0.33} and Ru{sub 0.286}Y{sub 0.714}, the Ru-Y system was numerically assessed with help of NANCYUN software to check the consistency between the experimental results and the phase diagram proposed in the literature.

  20. Heart Failure Readmission Reduction.

    PubMed

    Drozda, Joseph P; Smith, Donna A; Freiman, Paul C; Pursley, Janet; VanSlette, Jeffrey A; Smith, Timothy R

    Little is known regarding effectiveness of readmission reduction programs over time. The Heart Failure Management Program (HFMP) of St. John's Physician Group Practice (PGP) Demonstration provided an opportunity to assess outcomes over an extended period. Data from an electronic health record, an inpatient database, a disease registry, and the Social Security Death Master File were analyzed for patients admitted with heart failure (HF) for 5 years before (Period 1) and 5 years after (Period 2) inception of PGP. HF admissions decreased (Period 1, 58.3/month; Period 2, 52.4/month, P = .007). Thirty-day all-cause readmission rate dropped from Period 1 (annual average 18.8% [668/3545]) to year 1 of Period 2 (16.9% [136/804], P = .04) and remained stable thereafter (annual average 16.8% [589/3503]). Thirty-day mortality rate was flat throughout. HFMP was associated with decreased readmissions, primarily related to outpatient case management, while mortality remained stable.

  1. Effects of Three Diagram Instruction Methods on Transfer of Diagram Comprehension Skills: The Critical Role of Inference While Learning

    ERIC Educational Resources Information Center

    Cromley, Jennifer G.; Bergey, Bradley W.; Fitzhugh, Shannon; Newcombe, Nora; Wills, Theodore W.; Shipley, Thomas F.; Tanaka, Jacqueline C.

    2013-01-01

    Can students be taught to better comprehend the diagrams in their textbooks? Can such teaching transfer to uninstructed diagrams in the same domain or even in a new domain? What methods work best for these goals? Building on previous research showing positive results compared to control groups in both laboratory studies and short-term…

  2. Assessment of predictive models for the failure of titanium and ferrous alloys due to hydrogen effects. Report for the period of June 16 to September 15, 1981

    SciTech Connect

    Archbold, T.F.; Bower, R.B.; Polonis, D.H.

    1982-04-01

    The 1977 version of the Simpson-Puls-Dutton model appears to be the most amenable with respect to utilizing known or readily estimated quantities. The Pardee-Paton model requires extensive calculations involving estimated quantities. Recent observations by Koike and Suzuki on vanadium support the general assumption that crack growth in hydride forming metals is determined by the rate of hydride formation, and their hydrogen atmosphere-displacive transformation model is of potential interest in explaining hydrogen embrittlement in ferrous alloys as well as hydride formers. The discontinuous nature of cracking due to hydrogen embrittlement appears to depend very strongly on localized stress intensities, thereby pointing to the role of microstructure in influencing crack initiation, fracture mode and crack path. The initiation of hydrogen induced failures over relatively short periods of time can be characterized with fair reliability using measurements of the threshold stress intensity. The experimental conditions for determining K/sub Th/ and ..delta..K/sub Th/ are designed to ensure plane strain conditions in most cases. Plane strain test conditions may be viewed as a conservative basis for predicting delayed failure. The physical configuration of nuclear waste canisters may involve elastic/plastic conditions rather than a state of plane strain, especially with thin-walled vessels. Under these conditions, alternative predictive tests may be considered, including COD and R-curve methods. The double cantilever beam technique employed by Boyer and Spurr on titanium alloys offers advantages for examining hydrogen induced delayed failure over long periods of time. 88 references. (DLC)

  3. Recognition Failure: Another Case of Retrieval Failure

    ERIC Educational Resources Information Center

    Rabinowitz, Jan; And Others

    1977-01-01

    A theoretical explanation of the phenomenon of recognition failure and a presentation of seven experiments investigating performance. Recognition failure is reduced when a more stringent recognition criterion is used, essentially eliminated when the proper access test is used and significantly reduced when variability in recognition performance is…

  4. Oak Ridge National Laboratory Technology Logic Diagram. Volume 2, Technology Logic Diagram: Part B, Remedial Action

    SciTech Connect

    Not Available

    1993-09-01

    The Oak Ridge National Laboratory Technology Logic Diagram (TLD) was developed to provide a decision support tool that relates environmental restoration (ER) and waste management (WM) problems at Oak Ridge National Laboratory (ORNL) to potential technologies that can remediate these problems. The TLD identifies the research, development, demonstration, testing, and evaluation needed to develop these technologies to a state that allows technology transfer and application to decontamination and decommissioning (D&D), remedial action (RA), and WM activities. The TLD consists of three fundamentally separate volumes: Vol. 1 (Technology Evaluation), Vol. 2 (Technology Logic Diagram), and Vol. 3 (Technology Evaluation Data Sheets). Part A of Vols. 1. and 2 focuses on D&D. Part B of Vols. 1 and 2 focuses on the RA of contaminated facilities. Part C of Vols. 1 and 2 focuses on WM. Each part of Vol. 1 contains an overview of the TLD, an explanation of the program-specific responsibilities, a review of identified technologies, and the rankings of remedial technologies. Volume 2 (Pts. A, B, and C) contains the logic linkages among EM goals, environmental problems, and the various technologies that have the potential to solve these problems. Volume 3 (Pts. A, B, and C) contains the TLD data sheets. Remedial action is the focus of Vol. 2, Pt. B, which has been divided into the three necessary subelements of the RA: characterization, RA, and robotics and automation. Each of these sections address general ORNL problems, which are then broken down by problem area/constituents and linked to potential remedial technologies. The diagrams also contain summary information about a technology`s status, its science and technology needs, and its implementation needs.

  5. Peripheral circulatory failure.

    PubMed

    Lodha, Rakesh; Kapoor, Vishal

    2003-02-01

    Shock is a syndrome arising from any of several initiating causes, resulting in inadequate tissue perfusion. Untreated shock due to any cause can lead to irreversible cellular damage. Early diagnosis and intervention are, therefore, key to improved outcomes. In children, hypotension is not a sensitive marker for diagnosing peripheral circulatory failure. A detailed evaluation to assess perfusion particularly estimating capillary refill time and end organ perfusion is required. Septic shock is a complex condition with varying contribution of hypovolemia, cardiac dysfunction and distributive shock. Aggressive fluid therapy in the early stages is essential to recovery. Understanding the pathophysiology will help in judicious use of vasoactive drugs. Newer modalities of treatment for severe sepsis and septic shock still need evaluation in children.

  6. The high-z quasar Hubble Diagram

    SciTech Connect

    Melia, Fulvio

    2014-01-01

    Two recent discoveries have made it possible for us to begin using high-z quasars as standard candles to construct a Hubble Diagram (HD) at z > 6. These are (1) the recognition from reverberation mapping that a relationship exists between the optical/UV luminosity and the distance of line-emitting gas from the central ionizing source. Thus, together with a measurement of the velocity of the line-emitting gas, e.g., via the width of BLR lines, such as Mg II, a single observation can therefore in principle provide a determination of the black hole's mass; and (2) the identification of quasar ULAS J1120+0641 at z = 7.085, which has significantly extended the redshift range of these sources, providing essential leverage when fitting theoretical luminosity distances to the data. In this paper, we use the observed fluxes and Mg II line-widths of these sources to show that one may reasonably test the predicted high-z distance versus redshift relationship, and we assemble a sample of 20 currently available high-z quasars for this exercise. We find a good match between theory and observations, suggesting that a more complete, high-quality survey may indeed eventually produce an HD to complement the highly-detailed study already underway (e.g., with Type Ia SNe, GRBs, and cosmic chronometers) at lower redshifts. With the modest sample we have here, we show that the R{sub h} = ct Universe and ΛCDM both fit the data quite well, though the smaller number of free parameters in the former produces a more favorable outcome when we calculate likelihoods using the Akaike, Kullback, and Bayes Information Criteria. These three statistical tools result in similar probabilities, indicating that the R{sub h} = ct Universe is more likely than ΛCDM to be correct, by a ratio of about 85% to 15%.

  7. Plasma Glutamine Concentrations in Liver Failure

    PubMed Central

    Helling, Gunnel; Wahlin, Staffan; Smedberg, Marie; Pettersson, Linn; Tjäder, Inga; Norberg, Åke; Rooyackers, Olav; Wernerman, Jan

    2016-01-01

    Background Higher than normal plasma glutamine concentration at admission to an intensive care unit is associated with an unfavorable outcome. Very high plasma glutamine levels are sometimes seen in both acute and chronic liver failure. We aimed to systematically explore the relation between different types of liver failure and plasma glutamine concentrations. Methods Four different groups of patients were studies; chronic liver failure (n = 40), acute on chronic liver failure (n = 20), acute fulminant liver failure (n = 20), and post-hepatectomy liver failure (n = 20). Child-Pugh and Model for End-stage Liver Disease (MELD) scores were assessed as indices of liver function. All groups except the chronic liver failure group were followed longitudinally during hospitalisation. Outcomes were recorded up to 48 months after study inclusion. Results All groups had individuals with very high plasma glutamine concentrations. In the total group of patients (n = 100), severity of liver failure correlated significantly with plasma glutamine concentration, but the correlation was not strong. Conclusion Liver failure, regardless of severity and course of illness, may be associated with a high plasma glutamine concentration. Further studies are needed to understand whether high glutamine levels should be regarded as a biomarker or as a contributor to symptomatology in liver failure. PMID:26938452

  8. Fluid management strategies in heart failure.

    PubMed

    Albert, Nancy M

    2012-04-01

    In patients with chronic heart failure, fluid retention (or hypervolemia) is often the stimulus for acute decompensated heart failure that requires hospitalization. The pathophysiology of fluid retention is complex and involves both hemodynamic and clinical congestion. Signs and symptoms of both hemodynamic and clinical congestion should be assessed serially during hospitalization. Core heart failure drug and cardiac device therapies should be provided, and ultrafiltration may be warranted. Critical care, intermediate care, and telemetry nurses have roles in both assessment and management of patients hospitalized with acute decompensated heart failure and fluid retention. Nurse administrators and managers have heightened their attention to fluid retention because the Medicare performance measure known as the risk-standardized 30-day all-cause readmission rate after heart failure hospitalization can be attenuated by fluid management strategies initiated by nurses during a patient's hospitalization.

  9. Penguin-like diagrams from the standard model

    SciTech Connect

    Ping, Chia Swee

    2015-04-24

    The Standard Model is highly successful in describing the interactions of leptons and quarks. There are, however, rare processes that involve higher order effects in electroweak interactions. One specific class of processes is the penguin-like diagram. Such class of diagrams involves the neutral change of quark flavours accompanied by the emission of a gluon (gluon penguin), a photon (photon penguin), a gluon and a photon (gluon-photon penguin), a Z-boson (Z penguin), or a Higgs-boson (Higgs penguin). Such diagrams do not arise at the tree level in the Standard Model. They are, however, induced by one-loop effects. In this paper, we present an exact calculation of the penguin diagram vertices in the ‘tHooft-Feynman gauge. Renormalization of the vertex is effected by a prescription by Chia and Chong which gives an expression for the counter term identical to that obtained by employing Ward-Takahashi identity. The on-shell vertex functions for the penguin diagram vertices are obtained. The various penguin diagram vertex functions are related to one another via Ward-Takahashi identity. From these, a set of relations is obtained connecting the vertex form factors of various penguin diagrams. Explicit expressions for the gluon-photon penguin vertex form factors are obtained, and their contributions to the flavor changing processes estimated.

  10. Penguin-like diagrams from the standard model

    NASA Astrophysics Data System (ADS)

    Ping, Chia Swee

    2015-04-01

    The Standard Model is highly successful in describing the interactions of leptons and quarks. There are, however, rare processes that involve higher order effects in electroweak interactions. One specific class of processes is the penguin-like diagram. Such class of diagrams involves the neutral change of quark flavours accompanied by the emission of a gluon (gluon penguin), a photon (photon penguin), a gluon and a photon (gluon-photon penguin), a Z-boson (Z penguin), or a Higgs-boson (Higgs penguin). Such diagrams do not arise at the tree level in the Standard Model. They are, however, induced by one-loop effects. In this paper, we present an exact calculation of the penguin diagram vertices in the `tHooft-Feynman gauge. Renormalization of the vertex is effected by a prescription by Chia and Chong which gives an expression for the counter term identical to that obtained by employing Ward-Takahashi identity. The on-shell vertex functions for the penguin diagram vertices are obtained. The various penguin diagram vertex functions are related to one another via Ward-Takahashi identity. From these, a set of relations is obtained connecting the vertex form factors of various penguin diagrams. Explicit expressions for the gluon-photon penguin vertex form factors are obtained, and their contributions to the flavor changing processes estimated.

  11. Localization phase diagram of two-dimensional quantum percolation

    NASA Astrophysics Data System (ADS)

    Dillon, Brianna S.; Nakanishi, Hisao

    2014-12-01

    We examine quantum percolation on a square lattice with random dilution up to q = 38% and energy 0.001 ≤ E ≤ 1.6 (measured in units of the hopping matrix element), using numerical calculations of the transmission coefficient at a much larger scale than previously. Our results confirm the previous finding that the two dimensional quantum percolation model exhibits localization-delocalization transitions, where the localized region splits into an exponentially localized region and a power-law localization region. We determine a fuller phase diagram confirming all three regions for energies as low as E = 0.1, and the delocalized and exponentially localized regions for energies down to E = 0.001. We also examine the scaling behavior of the residual transmission coefficient in the delocalized region, the power law exponent in the power-law localized region, and the localization length in the exponentially localized region. Our results suggest that the residual transmission at the delocalized to power-law localized phase boundary may be discontinuous, and that the localization length is likely not to diverge with a power-law at the exponentially localized to power-law localized phase boundary. However, further work is needed to definitively assess the characters of the two phase transitions as well as the nature of the intermediate power-law regime.

  12. Failure in glass

    NASA Technical Reports Server (NTRS)

    Keeton, S. C.

    1972-01-01

    Review of state of the art concerning glass failure mechanisms and fatigue theories discusses brittle fracture in glass, fatigue mechanisms, fatigue behavior, environmental effects on failure rate, and aging.

  13. [Understanding heart failure].

    PubMed

    Boo, José Fernando Guadalajara

    2006-01-01

    Heart failure is a disease with several definitions. The term "heart failure" is used by has brougth about confusion in the terminology. For this reason, the value of the ejection fraction (< 0.40 or < 0.35) is used in most meganalyses on the treatment of heart failure, avoiding the term "heart failure" that is a confounding concept. In this paper we carefully analyze the meaning of contractility, ventricular function or performance, preload, afterload, heart failure, compensation mechanisms in heart failure, myocardial oxygen consumption, inadequate, adequate and inappropriate hypertrophy, systole, diastole, compliance, problems of relaxation, and diastolic dysfunction. Their definitions are supported by the original scientific descriptions in an attempt to clarify the concepts about ventricular function and heart failure and, in this way, use the same scientific language about the meaning of ventricular function, heart failure, and diastolic dysfunction.

  14. A Three-dimensional Topological Model of Ternary Phase Diagram

    NASA Astrophysics Data System (ADS)

    Mu, Yingxue; Bao, Hong

    2017-01-01

    In order to obtain a visualization of the complex internal structure of ternary phase diagram, the paper realized a three-dimensional topology model of ternary phase diagram with the designed data structure and improved algorithm, under the guidance of relevant theories of computer graphics. The purpose of the model is mainly to analyze the relationship between each phase region of a ternary phase diagram. The model not only obtain isothermal section graph at any temperature, but also extract a particular phase region in which users are interested.

  15. Cu-Zn binary phase diagram and diffusion couples

    NASA Technical Reports Server (NTRS)

    Mccoy, Robert A.

    1992-01-01

    The objectives of this paper are to learn: (1) what information a binary phase diagram can yield; (2) how to construct and heat treat a simple diffusion couple; (3) how to prepare a metallographic sample; (4) how to operate a metallograph; (5) how to correlate phases found in the diffusion couple with phases predicted by the phase diagram; (6) how diffusion couples held at various temperatures could be used to construct a phase diagram; (7) the relation between the thickness of an intermetallic phase layer and the diffusion time; and (8) the effect of one species of atoms diffusing faster than another species in a diffusion couple.

  16. Failures in psychodynamic psychotherapy.

    PubMed

    Gold, Jerry; Stricker, George

    2011-11-01

    This article addresses the issue of failures in psychodynamic psychotherapy. Drawing on the clinical and research literatures, and utilizing our clinical experiences, we first describe and define criteria for success and failure in treatment. We then review five factors that can lead to failure: client factors, therapist factors, technical factors, relationship factors, and environmental factors. We illustrate our presentation with a case example, and conclude by discussing ways in which the likelihood of failures in psychodynamic treatment can be lowered.

  17. To use or not to use diagrams: The effect of drawing a diagram in solving introductory physics problems

    NASA Astrophysics Data System (ADS)

    Maries, Alexandru; Singh, Chandralekha

    2013-01-01

    Drawing appropriate diagrams is a useful problem solving heuristic that can transform a given problem into a representation that is easier to exploit for solving it. A major focus while helping introductory physics students learn problem solving is to help them appreciate that drawing diagrams facilitates problem solution. We conducted an investigation in which 111 students in an algebra-based introductory physics course were subjected to two different interventions during recitation quizzes throughout the semester. They were either (1) asked to solve problems in which the diagrams were drawn for them or (2) explicitly told to draw a diagram. A comparison group was not given any instruction regarding diagrams. We developed a rubric to score the problem-solving performance of students in different intervention groups. We investigated two problems involving electric field and electric force and found that students who draw expert-like diagrams are more successful problem solvers and that a higher level of detail in a student's diagram corresponds to a better score.

  18. Ammonia tank failure

    SciTech Connect

    Sweat, M.E.

    1983-04-01

    An ammonia tank failure at Hawkeye Chemical of Clinton, Iowa is discussed. The tank was a double-wall, 27,000 metric-ton tank built in 1968 and commissioned in December 1969. The paper presented covers the cause of the failure, repair, and procedural changes made to prevent recurrence of the failure. (JMT)

  19. Cosmological test with the QSO Hubble diagram

    NASA Astrophysics Data System (ADS)

    López-Corredoira, M.; Melia, F.; Lusso, E.; Risaliti, G.

    2016-03-01

    A Hubble diagram (HD) has recently been constructed in the redshift range 0 ≲ z ≲ 6.5 using a nonlinear relation between the ultraviolet (UV) and X-ray luminosities of quasi stellar objects (QSOs). The Type Ia Supernovae (SN) HD has already provided a high-precision test of cosmological models, but the fact that the QSO distribution extends well beyond the supernova range (z ≲ 1.8), in principle provides us with an important complementary diagnostic whose significantly greater leverage in z can impose tighter constraints on the distance versus redshift relationship. In this paper, we therefore perform an independent test of nine different cosmological models, among which six are expanding, while three are static. Many of these are disfavored by other kinds of observations (including the aforementioned Type Ia SNe). We wish to examine whether the QSO HD confirms or rejects these earlier conclusions. We find that four of these models (Einstein-de Sitter, the Milne universe, the static universe with simple tired light and the static universe with plasma tired light) are excluded at the > 99% C.L. The quasi-steady state model is excluded at > 95% C.L. The remaining four models (ΛCDM/wCDM, the Rh = ct universe, the Friedmann open universe and a static universe with a linear Hubble law) all pass the test. However, only ΛCDM/wCDM and Rh = ct also pass the Alcock-Paczyński (AP) test. The optimized parameters in ΛCDM/wCDM are Ωm = 0.20-0.20+0.24 and wde = -1.2-∞+1.6 (the dark energy equation-of-state). Combined with the AP test, these values become Ωm = 0.38-0.19+0.20 and wde = -0.28-0.40+0.52. But whereas this optimization of parameters in ΛCDM/wCDM creates some tension with their concordance values, the Rh = ct universe has the advantage of fitting the QSO and AP data without any free parameters.

  20. Assessment of the Relationship between Galectin-3 and Ejection Fraction and Functional Capacity in the Patients with Compensated Systolic Heart Failure

    PubMed Central

    Atabakhshian, Roya; Kazerouni, Faranak; Raygan, Fariba; Amirrasouli, Hushang; Rahimipour, Ali; Shakeri, Nezhat

    2014-01-01

    Background: Galectin-3 is a soluble ß-galactoside–binding lectin released by activated cardiac macrophages. Galectin-3 has been proposed for diagnosis and prognosis of HF patients. Objectives: The present study aimed to investigate the relationship between galectin-3 as a biomarker and ejection fraction and functional capacity in the patients with compensated systolic heart failure. Patients and Methods: In this study, serum levels of Galectin-3 were measured in 76 patients with compensated heart failure with New York Heart Association class I–IV and left ventricular ejection fraction < 45%. Galectin-3 was measured by an ELISA kit. Besides, echocardiography was used to evaluate left ventricular ejection fraction. Additionally, functional capacity was determined based on the patients’ ability to perform a set of activities. After all, the data were analyzed used t-test, Kruskal-Wallis, one–way ANOVA, and chi-square test. P < 0.05 was considered as statistically significant. Results: The patients’ age ranged from 45 to 75 years, with the mean age of 63.85 ± 9 years. In addition 57.9% of the patients were male. The results revealed no significant correlation between Galectin-3 and age, body mass index, and estimated glomerular filtration rate. Also, no significant correlation was observed between Galectin-3 levels and left ventricular ejection fraction (P = 0.166) and functional capacity (P = 0.420). Yet, a significant difference was found between males and females regarding the mean of Galectin-3 (P = 0.039). Conclusions: The study results suggested that Galectin-3 could not be used as a marker of disease progression in the patients under treatment, which could probably be the result of medication use in these patients. PMID:25614856

  1. The Fermion Representation of Quantum Toroidal Algebra on 3D Young Diagrams

    NASA Astrophysics Data System (ADS)

    Cai, Li-Qiang; Wang, Li-Fang; Wu, Ke; Yang, Jie

    2014-07-01

    We develop an equivalence between the diagonal slices and the perpendicular slices of 3D Young diagrams via Maya diagrams. Furthermore, we construct the fermion representation of quantum toroidal algebra on the 3D Young diagrams perpendicularly sliced.

  2. 76 FR 2919 - Outer Continental Shelf Official Protraction Diagram and Supplemental Official Outer Continental...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-18

    ... Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf Official Protraction Diagram and Supplemental Official Outer Continental Shelf Block Diagrams AGENCY: Bureau of Ocean... American Datum of 1983 (NAD 83) Outer Continental Shelf Official Protraction Diagram and...

  3. 76 FR 54787 - Outer Continental Shelf Official Protraction Diagram, Lease Maps, and Supplemental Official Outer...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-02

    ... Bureau of Ocean Energy Management, Regulation and Enforcement Outer Continental Shelf Official Protraction Diagram, Lease Maps, and Supplemental Official Outer Continental Shelf Block Diagrams AGENCY... revised North American Datum of 1927 (NAD 27) Outer Continental Shelf Official Protraction Diagram,...

  4. Flame Deflector Section, Elevation, Water Supply Flow Diagram, Exploded ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Flame Deflector - Section, Elevation, Water Supply Flow Diagram, Exploded Deflector Manifolds, and Interior Perspective - Marshall Space Flight Center, F-1 Engine Static Test Stand, On Route 565 between Huntsville and Decatur, Huntsville, Madison County, AL

  5. Influence diagrams as oil spill decision science tools

    EPA Science Inventory

    Making inferences on risks to ecosystem services (ES) from ecological crises can be more reliably handled using decision science tools. Influence diagrams (IDs) are probabilistic networks that explicitly represent the decisions related to a problem and evidence of their influence...

  6. 21. Power plant engine fuel oil piping diagrams, sheet 83 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. Power plant engine fuel oil piping diagrams, sheet 83 of 130 - Naval Air Station Fallon, Power Plant, 800 Complex, off Carson Road near intersection of Pasture & Berney Roads, Fallon, Churchill County, NV

  7. Phase diagram for assembly of biologically-active peptide amphiphiles.

    PubMed

    Tsonchev, Stefan; Niece, Krista L; Schatz, George C; Ratner, Mark A; Stupp, Samuel I

    2008-01-17

    We construct a phase diagram for self-assembling biologically active peptide amphiphiles. The structure and stability of the assemblies are studied as a function of pH and salinity of the solution. The general features of the phase diagram are predicted based on theoretical modeling of the self-assembly process, as well as experimental data, and further experiments are performed to verify and ascertain the boundary locations of the diagram. Depending on solution conditions, the amphiphiles can form cylindrical or spherical micelles, intermediate structures between these, or may not assemble at all. We also demonstrate that changing conditions may result in phase transitions among these structures. This type of phase diagram could be useful in the design of certain supramolecular nanostructures by providing information on the necessary conditions to form them.

  8. 49 CFR 1152.10 - System diagram map.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) The system diagram map shall be color-coded to show the 5 categories of lines as follows: (1) Red... shall designate those lines described in § 1152.10(b)(4); and (5) Black or dark blue shall...

  9. 129. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LIGHTING DIAGRAM. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    129. PLAN OF IMPROVEMENT, HUNTINGTON BEACH MUNICIPAL PIER: LIGHTING DIAGRAM. Sheet lO of 11 (#3283) - Huntington Beach Municipal Pier, Pacific Coast Highway at Main Street, Huntington Beach, Orange County, CA

  10. Penguin diagram dominance in radiative weak decays of bottom baryons

    SciTech Connect

    Kohara, Yoji

    2005-05-01

    Radiative weak decays of antitriplet bottom baryons are studied under the assumption of penguin diagram dominance and flavor-SU(3) (or SU(2)) symmetry. Relations among decay rates of various decay modes are derived.

  11. 8. Photocopy of top half of an 1855 organizational diagram ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Photocopy of top half of an 1855 organizational diagram of the New York and Erie Railroad. Original in the collections of the Library of Congress. - Erie Railway, New Jersey, New York, Pennsylvania, Deposit, Broome County, NY

  12. 9. Photocopy of bottom half of an 1855 organizational diagram ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Photocopy of bottom half of an 1855 organizational diagram of the New York and Erie Railroad. Original in the collections of the Library of Congress. - Erie Railway, New Jersey, New York, Pennsylvania, Deposit, Broome County, NY

  13. Adding Value to Force Diagrams: Representing Relative Force Magnitudes

    NASA Astrophysics Data System (ADS)

    Wendel, Paul

    2011-05-01

    Nearly all physics instructors recognize the instructional value of force diagrams, and this journal has published several collections of exercises to improve student skill in this area.1-4 Yet some instructors worry that too few students perceive the conceptual and problem-solving utility of force diagrams,4-6 and over recent years a rich variety of approaches has been proposed to add value to force diagrams. Suggestions include strategies for identifying candidate forces,6,7 emphasizing the distinction between "contact" and "noncontact" forces,5,8 and the use of computer-based tutorials.9,10 Instructors have suggested a variety of conventions for constructing force diagrams, including approaches to arrow placement and orientation2,11-13 and proposed notations for locating forces or marking action-reaction force pairs.8,11,14,15

  14. Analysing Vee Diagram Reflections to Explore Pre-Service Science Teachers' Understanding the Nature of Science in Biology

    ERIC Educational Resources Information Center

    Savran-Gencer, Ayse

    2014-01-01

    Vee diagrams have been a metacognitive tool to help in learning the nature and structure of knowledge by reflecting on the scientific process and making knowledge much more explicit to learners during the practical work. This study aimed to assess pre-service science teachers' understanding some aspects of NOS by analyzing their reflections on the…

  15. Heart Failure: A Primer.

    PubMed

    Lee, Christopher S; Auld, Jonathan

    2015-12-01

    Heart failure is a complex and multisystem clinical syndrome that results from impaired ventricular contractility and/or relaxation. Hypertension, diabetes mellitus, and coronary artery disease are common antecedents to heart failure. The main pathogenic mechanisms involved in heart failure include sympathetic nervous and renin-angiotensin-aldosterone system activation, as well as inflammation. A detailed history and physical examination and additional diagnostic tests may be needed to diagnose heart failure. Most treatment strategies target neurohormonal systems. Nonpharmacologic interventions and effective engagement in self-care are also important in overall heart failure management. Therapeutic strategies are geared toward prolonging life and optimizing quality of life.

  16. The failure of earthquake failure models

    USGS Publications Warehouse

    Gomberg, J.

    2001-01-01

    In this study I show that simple heuristic models and numerical calculations suggest that an entire class of commonly invoked models of earthquake failure processes cannot explain triggering of seismicity by transient or "dynamic" stress changes, such as stress changes associated with passing seismic waves. The models of this class have the common feature that the physical property characterizing failure increases at an accelerating rate when a fault is loaded (stressed) at a constant rate. Examples include models that invoke rate state friction or subcritical crack growth, in which the properties characterizing failure are slip or crack length, respectively. Failure occurs when the rate at which these grow accelerates to values exceeding some critical threshold. These accelerating failure models do not predict the finite durations of dynamically triggered earthquake sequences (e.g., at aftershock or remote distances). Some of the failure models belonging to this class have been used to explain static stress triggering of aftershocks. This may imply that the physical processes underlying dynamic triggering differs or that currently applied models of static triggering require modification. If the former is the case, we might appeal to physical mechanisms relying on oscillatory deformations such as compaction of saturated fault gouge leading to pore pressure increase, or cyclic fatigue. However, if dynamic and static triggering mechanisms differ, one still needs to ask why static triggering models that neglect these dynamic mechanisms appear to explain many observations. If the static and dynamic triggering mechanisms are the same, perhaps assumptions about accelerating failure and/or that triggering advances the failure times of a population of inevitable earthquakes are incorrect.

  17. 49 CFR Appendix B to Part 230 - Diagrams and Drawings

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Diagrams and Drawings B Appendix B to Part 230..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Pt. 230, App. B Appendix B to Part 230—Diagrams and Drawings ER17No99.015 ER17No99.016 ER17No99.017 ER17No99.018...

  18. 49 CFR Appendix B to Part 230 - Diagrams and Drawings

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Diagrams and Drawings B Appendix B to Part 230..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Pt. 230, App. B Appendix B to Part 230—Diagrams and Drawings ER17No99.015 ER17No99.016 ER17No99.017 ER17No99.018...

  19. 49 CFR Appendix B to Part 230 - Diagrams and Drawings

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Diagrams and Drawings B Appendix B to Part 230..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Pt. 230, App. B Appendix B to Part 230—Diagrams and Drawings ER17No99.015 ER17No99.016 ER17No99.017 ER17No99.018...

  20. 49 CFR Appendix B to Part 230 - Diagrams and Drawings

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Diagrams and Drawings B Appendix B to Part 230..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Pt. 230, App. B Appendix B to Part 230—Diagrams and Drawings ER17No99.015 ER17No99.016 ER17No99.017 ER17No99.018...

  1. 49 CFR Appendix B to Part 230 - Diagrams and Drawings

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Diagrams and Drawings B Appendix B to Part 230..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Pt. 230, App. B Appendix B to Part 230—Diagrams and Drawings ER17No99.015 ER17No99.016 ER17No99.017 ER17No99.018...

  2. CALCULATING ASTEROSEISMIC DIAGRAMS FOR SOLAR-LIKE OSCILLATIONS

    SciTech Connect

    White, Timothy R.; Bedding, Timothy R.; Stello, Dennis; Huber, Daniel; Christensen-Dalsgaard, Jorgen; Kjeldsen, Hans

    2011-12-20

    With the success of the Kepler and CoRoT missions, the number of stars with detected solar-like oscillations has increased by several orders of magnitude; for the first time we are able to perform large-scale ensemble asteroseismology of these stars. In preparation for this golden age of asteroseismology we have computed expected values of various asteroseismic observables from models of varying mass and metallicity. The relationships between these asteroseismic observables, such as the separations between mode frequencies, are able to significantly constrain estimates of the ages and masses of these stars. We investigate the scaling relation between the large frequency separation, {Delta}{nu}, and mean stellar density. Furthermore we present model evolutionary tracks for several asteroseismic diagrams. We have extended the so-called C-D diagram beyond the main sequence to the subgiants and the red giant branch. We also consider another asteroseismic diagram, the {epsilon} diagram, which is more sensitive to variations in stellar properties at the subgiant stages and can aid in determining the correct mode identification. The recent discovery of gravity-mode period spacings in red giants forms the basis for a third asteroseismic diagram. We compare the evolutionary model tracks in these asteroseismic diagrams with results from pre-Kepler studies of solar-like oscillations and early results from Kepler.

  3. Endorectal MRI assessment of local relapse after surgery for prostate cancer: A model to define treatment field guidelines for adjuvant radiotherapy in patients at high risk for local failure

    SciTech Connect

    Miralbell, Raymond . E-mail: Raymond.Miralbell@hcuge.ch; Vees, Hansjoerg; Lozano, Joan; Khan, Haleem; Molla, Meritxell; Hidalgo, Alberto; Linero, Dolors; Rouzaud, Michel

    2007-02-01

    Purpose: To assess the role of endorectal magnetic resonance imaging (MRI) in defining local relapse after radical prostatectomy for prostate cancer to help to reassess the clinical target volume (CTV) for adjuvant postprostatectomy radiotherapy. Methods and Materials: Sixty patients undergoing an endorectal MRI before salvage radiotherapy were selected. Spatial coordinates of the relapses were assessed using two reference points: the inferior border of the pubic symphysis (point 1) and the urethro-vesical anastomosis (point 2). Every lesion on MRI was delineated on the planning computed tomography and center of mass coordinates were plotted in two separate diagrams (along the x, y, and z axes) with the urethro-vesical anastomosis as the coordinate origin. An 'ideal' CTV was constructed, centered at a point defined by the mathematical means of each of the three coordinates with dimensions defined as twice 2 standard deviations in each of the three axes. The dosimetric impact of the new CTV definition was evaluated in six adjuvantly treated patients. Results: The ideal CTV center of mass was located at coordinates 0 (x), -5 (y), and -3 (z) mm with SDs of 6 (x), 6 (y), and 9 (z) mm, respectively. The CTV size was 24 (x) x 24 (y) x 36 (z) mm. Significant rectal sparing was observed with the new CTV. Conclusions: A CTV with an approximately cylindrical shape ({approx}4 x 3 cm) centered 5 mm posterior and 3 mm inferior to the urethro-vesical anastomosis was defined. Such CTV may reduce the irradiation of normal nontarget tissue in the pelvis potentially improving treatment tolerance.

  4. [Comparison of film-screen combination in a contrast detail diagram and with interactive image analysis. 1: Contrast detail diagram].

    PubMed

    Hagemann, G; Eichbaum, G

    1997-07-01

    The following three film-screen combinations were compared: a) a combination of anticrossover film and UV-light emitting screens, b) a combination of blue-light emitting screens and film, and c) a conventional green fluorescing screen film combination. Radiographs of a specially designed plexiglass phantom (0.2 x 0.2 x 0.12 m3) were obtained that contained bar patterns of lead and plaster (calcium sulfate) to test high and intermediate contrast resolution and bar patterns of air to test low contrast resolution, respectively. An aluminum step wedge was integrated to evaluate dose-density curves of the radiographs. The dose values for the various step thicknesses were measured as percentage of the dose value in air for 60, 81, and 117 kV. Exposure conditions were the following: 12 pulse generator, 0.6 mm focus size, 4.7 mm aluminum prefilter, a grid with 40 lines/cm (12:1), and a focus-detector distance of 1.15 m. The thresholds of visible bars of the various pattern materials were assessed by seven radiologists, one technician, and the authors. The resulting contrast detail diagram could not prove any significant differences between the three tested screen film combinations. The pairwise comparison, however, found 8 of the 18 paired differences to be statistically significant between the conventional and the two new screen-film combinations. The authors concluded that subjective visual assessment of the threshold in a contrast detail study alone is of only limited value to grade image quality if no well-defined criteria are used (BIR report 20 [1989] 137-139). The statistical approach of paired differences of the estimated means appeared to be more appropriate.

  5. Quantitative risk assessment system (QRAS)

    NASA Technical Reports Server (NTRS)

    Weinstock, Robert M (Inventor); Smidts, Carol S (Inventor); Mosleh, Ali (Inventor); Chang, Yung-Hsien (Inventor); Swaminathan, Sankaran (Inventor); Groen, Francisco J (Inventor); Tan, Zhibin (Inventor)

    2001-01-01

    A quantitative risk assessment system (QRAS) builds a risk model of a system for which risk of failure is being assessed, then analyzes the risk of the system corresponding to the risk model. The QRAS performs sensitivity analysis of the risk model by altering fundamental components and quantifications built into the risk model, then re-analyzes the risk of the system using the modifications. More particularly, the risk model is built by building a hierarchy, creating a mission timeline, quantifying failure modes, and building/editing event sequence diagrams. Multiplicities, dependencies, and redundancies of the system are included in the risk model. For analysis runs, a fixed baseline is first constructed and stored. This baseline contains the lowest level scenarios, preserved in event tree structure. The analysis runs, at any level of the hierarchy and below, access this baseline for risk quantitative computation as well as ranking of particular risks. A standalone Tool Box capability exists, allowing the user to store application programs within QRAS.

  6. “Not the ‘Grim Reaper Service’”: An Assessment of Provider Knowledge, Attitudes, and Perceptions Regarding Palliative Care Referral Barriers in Heart Failure

    PubMed Central

    Kavalieratos, Dio; Mitchell, Emma M.; Carey, Timothy S.; Dev, Sandesh; Biddle, Andrea K.; Reeve, Bryce B.; Abernethy, Amy P.; Weinberger, Morris

    2014-01-01

    Background Although similar to cancer patients regarding symptom burden and prognosis, patients with heart failure (HF) tend to receive palliative care far less frequently. We sought to explore factors perceived by cardiology, primary care, and palliative care providers to impede palliative care referral for HF patients. Methods and Results We conducted semistructured interviews regarding (1) perceived needs of patients with advanced HF; (2) knowledge, attitudes, and experiences with specialist palliative care; (3) perceived indications for and optimal timing of palliative care referral in HF; and (4) perceived barriers to palliative care referral. Two investigators analyzed data using template analysis, a qualitative technique. We interviewed 18 physician, nurse practitioner, and physician assistant providers from 3 specialties: cardiology, primary care, and palliative care. Providers had limited knowledge regarding what palliative care is, and how it can complement traditional HF therapy to decrease HF‐related suffering. Interviews identified several potential barriers: the unpredictable course of HF; lack of clear referral triggers across the HF trajectory; and ambiguity regarding what differentiates standard HF therapy from palliative care. Nevertheless, providers expressed interest for integrating palliative care into traditional HF care, but were unsure of how to initiate collaboration. Conclusions Palliative care referral for HF patients may be suboptimal due to limited provider knowledge and misperceptions of palliative care as a service reserved for those near death. These factors represent potentially modifiable targets for provider education, which may help to improve palliative care referral for HF patients with unresolved disease‐related burden. PMID:24385453

  7. Kidney Failure: What to Expect

    MedlinePlus

    ... Kidneys & How They Work Kidney Disease A-Z Kidney Failure What is kidney failure and how is it treated? Kidney failure ... Methods for Kidney Failure: Peritoneal Dialysis . Peritoneal dialysis Kidney Transplant A kidney transplant places a healthy kidney ...

  8. The participatory vulnerability scoping diagram - deliberative risk ranking for community water systems

    USGS Publications Warehouse

    Howe, Peter D.; Yarnal, Brent; Coletti, Alex; Wood, Nathan J.

    2013-01-01

    Natural hazards and climate change present growing challenges to community water system (CWS) managers, who are increasingly turning to vulnerability assessments to identify, prioritize, and adapt to risks. Effectively assessing CWS vulnerability requires information and participation from various sources, one of which is stakeholders. In this article, we present a deliberative risk-ranking methodology, the participatory vulnerability scoping diagram (P-VSD), which allows rapid assessment and integration of multiple stakeholder perspectives of vulnerability. This technique is based on methods of deliberative risk evaluation and the vulnerability scoping diagram. The goal of the methodology is to engage CWS managers and stakeholders collectively to provide qualitative contextual risk rankings as a first step in a vulnerability assessment. We conduct an initial assessment using a case study of CWS in two U.S. counties, sites with broadly similar exposures but differences in population, land use, and other social sensitivity factors. Results demonstrate that CWS managers and stakeholders in the two case study communities all share the belief that their CWS are vulnerable to hazards but differ in how this vulnerability manifests itself in terms of the exposure, sensitivity, and adaptive capacity of the system.

  9. Applications of Phase Diagrams in Metallurgy and Ceramics: Proceedings of a Workshop Held at the National Bureau of Standards, Gaithersburg, Maryland, January 10-12, 1977. Volumes 1 [and] 2.

    ERIC Educational Resources Information Center

    Carter, G. C., Ed.

    This document is a special National Bureau of Standards publication on a Workshop on Applications of Phase Diagrams in Metallurgy and Ceramics. The purposes of the Workshop were: (1) to assess the current national and international status of phase diagram determinations and evaluations for alloys, ceramics and semiconductors; (2) to determine the…

  10. Tensile failure criteria for fiber composite materials

    NASA Technical Reports Server (NTRS)

    Rosen, B. W.; Zweben, C. H.

    1972-01-01

    The analysis provides insight into the failure mechanics of these materials and defines criteria which serve as tools for preliminary design material selection and for material reliability assessment. The model incorporates both dispersed and propagation type failures and includes the influence of material heterogeneity. The important effects of localized matrix damage and post-failure matrix shear stress transfer are included in the treatment. The model is used to evaluate the influence of key parameters on the failure of several commonly used fiber-matrix systems. Analyses of three possible failure modes were developed. These modes are the fiber break propagation mode, the cumulative group fracture mode, and the weakest link mode. Application of the new model to composite material systems has indicated several results which require attention in the development of reliable structural composites. Prominent among these are the size effect and the influence of fiber strength variability.

  11. How to Recognize Success and Failure: Practical Assessment of an Evolving, First-Semester Laboratory Program Using Simple, Outcome-Based Tools

    ERIC Educational Resources Information Center

    Gron, Liz U.; Bradley, Shelly B.; McKenzie, Jennifer R.; Shinn, Sara E.; Teague, M. Warfield

    2013-01-01

    This paper presents the use of simple, outcome-based assessment tools to design and evaluate the first semester of a new introductory laboratory program created to teach green analytical chemistry using environmental samples. This general chemistry laboratory program, like many introductory courses, has a wide array of stakeholders within and…

  12. The Free-Body Diagram Revisited

    DTIC Science & Technology

    1980-05-01

    teaching introductory mechanics in the Department of Physics at the United States Military Academy. As Tipler Indicates in his textbook Physics, the...write Newton’s Second Law and solve the resulting equations. In his text, Physics Tipler points out that "many students’ errors can be traced to a...that Tipler is 5 correct in his assessment of student difficulties. The problem. of course, stems from insufficient emphasis by instructors. The

  13. Nitrile/Buna N Material Failure Assessment for an O-Ring used on the Gaseous Hydrogen Flow Control Valve (FCV) of the Space Shuttle Main Engine

    NASA Technical Reports Server (NTRS)

    Wingard, Doug

    2006-01-01

    After the rollout of Space Shuttle Discovery in April 2005 in preparation for return-to-flight, there was a failure of the Orbiter (OV-103) helium signature leak test in the gaseous hydrogen (GH2) system. Leakage was attributed to the Flow Control Valve (FCV) in Main Engine 3. The FCV determined to be the source of the leak for OV-103 is designated as LV-58. The nitrile/Buna N rubber O-ring seal was removed from LV-58, and failure analysis indicated radial cracks providing leak paths in one quadrant. Cracks were eventually found in 6 of 9 FCV O-rings among the three Shuttle Orbiters, though none were as severe as those for LV-58, OV-103. Testing by EM10 at MSFC on all 9 FCV O- rings included: laser dimensional, Shore A hardness and properties from a dynamic mechanical analyzer (DMA) and an Instron tensile machine. The following test data was obtained on the cracked quadrant of the LV-58, OV-103 O-ring: (1) the estimated compression set was only 9.5%, compared to none for the rest of the O-ring; (2) Shore A hardness for the O.D. was higher by almost 4 durometer points than for the rest of the O-ring; and (3) DMA data showed that the storage/elastic modulus E was almost 25% lower than for the rest of the O-ring. Of the 8 FCV O-rings tested on an Instron, 4 yielded tensile strengths that were below the MIL spec requirement of 1350 psi-a likely influence of rubber cracking. Comparisons were made between values of modulus determined by DNA (elastic) and Instron (Young s). Each nitrile/Buna N O-ring used in the FCV conforms to the MIL-P-25732C specification. A number of such O-rings taken from shelf storage at MSFC and Kennedy Space Center (KSC) were used to generate a reference curve of DMA glass transition temperature (Tg) vs. shelf storage time ranging from 8 to 26 years. A similar reference curve of TGA onset temperature (of rubber weight loss) vs. shelf storage time was also generated. The DMA and TGA data for the used FCV O-rings were compared to the reference

  14. Generation of Constant Life Diagram under Elevated Temperature Ratcheting of 316LN Stainless Steel

    NASA Astrophysics Data System (ADS)

    Sarkar, Aritra; Nagesha, A.; Sandhya, R.; Mathew, M. D.

    2016-04-01

    Combined influence of mean stress and stress amplitude on the cyclic life under elevated temperature (823-923 K) ratcheting of 316LN austenitic stainless steel is discussed. Constant life Haigh diagrams have been generated, using different combinations of stress amplitude and mean stress. In the plastic domain, the allowable stress was found to increase or decrease with mean stress depending on the temperature and combination of mean stress - stress amplitude employed. Strong influence of dynamic strain aging (DSA) was found at 823 K which affected the mode of deformation of the material in comparison with 923 K. Failure mode expressed through a fracture mechanism map was found to change from fatigue to necking depending on the test temperature as well as combinations of mean stress and stress amplitude. Occurrence of DSA at 823 K proved to be beneficial by way of extending the safe zone of operation to higher R-ratios in comparison with 923 K.

  15. Relation between strain dyssynchrony index determined by comprehensive assessment using speckle-tracking imaging and long-term outcome after cardiac resynchronization therapy for patients with heart failure.

    PubMed

    Tatsumi, Kazuhiro; Tanaka, Hidekazu; Matsumoto, Kensuke; Kaneko, Akihiro; Tsuji, Takayuki; Ryo, Keiko; Fukuda, Yuko; Norisada, Kazuko; Onishi, Tetsuari; Yoshida, Akihiro; Kawai, Hiroya; Hirata, Ken-Ichi

    2012-04-15

    Strain dyssynchrony index (SDI), which was a marker of dyssynchrony and residual myocardial contractility, can predict left ventricular reverse remodeling short-term after cardiac resynchronization therapy (CRT). We investigated SDI-predicted long-term outcome after CRT in patients with heart failure (HF). We studied 74 patients with HF who underwent CRT. SDI was calculated as the average difference between peak and end-systolic strain from 6 segments for radial and circumferential SDIs and 18 segments for longitudinal SDI using 2-dimensional speckle-tracking strain. Based on our previous findings, the predefined cutoff for significant dyssynchrony and residual myocardial contractility was a radial SDI ≥6.5%, a circumferential SDI ≥3.2%, and a longitudinal SDI ≥3.6%. The predefined principal outcome variable was the combined end point of death or hospitalization owing to deteriorating HF. Long-term follow-up after CRT was tracked over 4 years. The primary end point of prespecified events occurred in 14 patients (19%). An association with a favorable long-term outcome after CRT was observed in patients with significant radial, circumferential, and longitudinal SDIs (p <0.001, <0.005, and 0.010 vs patients without significant SDIs, respectively). Furthermore, cardiovascular event-free rate after CRT in patients with positivity of 3 for the 3 SDIs was 100% better than that in patients with positivity of 1 (52%, p <0.005) or 0 (31%, p <0.001) for the 3 SDIs. In conclusion, SDIs can successfully predict long-term outcome after CRT in patients with HF. Moreover, the approach combining the 3 types of SDI leads to a more accurate prediction than the use of individual parameters. These findings may have clinical implications in patients with CRT.

  16. Diagnostic accuracy of refractometer and Brix refractometer to assess failure of passive transfer in calves: protocol for a systematic review and meta-analysis.

    PubMed

    Buczinski, S; Fecteau, G; Chigerwe, M; Vandeweerd, J M

    2016-06-01

    Calves are highly dependent of colostrum (and antibody) intake because they are born agammaglobulinemic. The transfer of passive immunity in calves can be assessed directly by dosing immunoglobulin G (IgG) or by refractometry or Brix refractometry. The latter are easier to perform routinely in the field. This paper presents a protocol for a systematic review meta-analysis to assess the diagnostic accuracy of refractometry or Brix refractometry versus dosage of IgG as a reference standard test. With this review protocol we aim to be able to report refractometer and Brix refractometer accuracy in terms of sensitivity and specificity as well as to quantify the impact of any study characteristic on test accuracy.

  17. Early complications. Respiratory failure.

    PubMed

    Zwischenberger, J B; Alpard, S K; Bidani, A

    1999-08-01

    Pulmonary complications following thoracic surgery are common and associated with significant morbidity and mortality. Respiratory failure after pneumonectomy occurs in approximately 5% to 15% of cases and significantly increases patient mortality. Strategies for ventilator support are based on the nature of the underlying complication and the pathophysiology of respiratory failure. This article describes the cause and pathophysiology of respiratory failure and pulmonary embolus postpneumonectomy. Diagnosis, management, and innovative therapies are also reviewed.

  18. The Cu-Sn phase diagram, Part I: New experimental results.

    PubMed

    Fürtauer, S; Li, D; Cupid, D; Flandorfer, H

    2013-03-01

    Phase diagram investigation of the Cu-Sn system was carried out on twenty Cu-rich samples by thermal analysis (DTA), metallographic methods (EPMA/SEM-EDX) and crystallographic analysis (powder XRD, high temperature powder XRD). One main issue in this work was to investigate the high temperature phases beta (W-type) and gamma (BiF3-type) and to check the phase relations between them. In the high temperature powder XRD experiments the presence of the two-phase-field between the beta- and the gamma-phase could not be confirmed. Detailed study of primary literature together with our experimental results leads to a new phase diagram version with a higher order transformation between these two high temperature phases. The present work is designated as part I of our joint publication. The new findings described here have been included into a completely new thermodynamic assessment of the Cu-Sn phase diagram which is presented in part II.

  19. Failure to thrive.

    PubMed

    Krugman, Scott D; Dubowitz, Howard

    2003-09-01

    Failure to thrive is a condition commonly seen by primary care physicians. Prompt diagnosis and intervention are important for preventing malnutrition and developmental sequelae. Medical and social factors often contribute to failure to thrive. Either extreme of parental attention (neglect or hypervigilance) can lead to failure to thrive. About 25 percent of normal infants will shift to a lower growth percentile in the first two years of life and then follow that percentile; this should not be diagnosed as failure to thrive. Infants with Down syndrome, intrauterine growth retardation, or premature birth follow different growth patterns than normal infants. Many infants with failure to thrive are not identified unless careful attention is paid to plotting growth parameters at routine checkups. A thorough history is the best guide to establishing the etiology of the failure to thrive and directing further evaluation and management. All children with failure to thrive need additional calories for catch-up growth (typically 150 percent of the caloric requirement for their expected, not actual, weight). Few need laboratory evaluation. Hospitalization is rarely required and is indicated only for severe failure to thrive and for those whose safety is a concern. A multidisciplinary approach is recommended when failure to thrive persists despite intervention or when it is severe.

  20. Assessing Educational Processes Using Total-Quality-Management Measurement Tools.

    ERIC Educational Resources Information Center

    Macchia, Peter, Jr.

    1993-01-01

    Discussion of the use of Total Quality Management (TQM) assessment tools in educational settings highlights and gives examples of fishbone diagrams, or cause and effect charts; Pareto diagrams; control charts; histograms and check sheets; scatter diagrams; and flowcharts. Variation and quality are discussed in terms of continuous process…

  1. Renal failure in burn patients: a review

    PubMed Central

    Emara, S.S.; Alzaylai, A.A.

    2013-01-01

    Summary Burn care providers are usually challenged by multiple complications during the management of acute burns. One of the most common complications worldwide is renal failure. This article reviews the various aspects of renal failure management in burn patients. Two different types of renal failures develop in these patients. The different aetiological factors, incidence, suspected prognosis, ways of diagnosing, as well as prevention methods, and the most accepted treatment modalities are all discussed. A good understanding and an effective assessment of the problem help to reduce both morbidity and mortality in burn management. PMID:23966893

  2. Renal failure in burn patients: a review.

    PubMed

    Emara, S S; Alzaylai, A A

    2013-03-31

    Burn care providers are usually challenged by multiple complications during the management of acute burns. One of the most common complications worldwide is renal failure. This article reviews the various aspects of renal failure management in burn patients. Two different types of renal failures develop in these patients. The different aetiological factors, incidence, suspected prognosis, ways of diagnosing, as well as prevention methods, and the most accepted treatment modalities are all discussed. A good understanding and an effective assessment of the problem help to reduce both morbidity and mortality in burn management.

  3. Validating IC early-failure simulation

    NASA Astrophysics Data System (ADS)

    Moosa, Mohamod S.; Poole, Kelvin F.; Grams, Michael L.

    1995-09-01

    Early failures are the dominant concern as integrated circuit technology matures into consistently producing systems of high reliability. These failures are attributed to the presence of randomly occurring defects in elementary objects (contacts, vias, metal runs, gate oxides, bonds etc.) that result in extrinsic rather than intrinsic (wearout-related) mortality. A model relating system failure to failure at the elementary objective level has been developed. Reliability is modeled as a function of circuit architecture, mask layout, material properties, life-test data, worst-case use-conditions and the processing environment. The effects of competing failure mechanisms and the presence of redundant sub-systems are accounted for. Hierarchy is exploited in the analysis, allowing large scale designs to be simulated. Experimental validation of the modeling of oxide leakage related failure, based on correlation between actual failures reported for a production integrated circuit and Monte Carlo simulations that incorporate wafer-level test results and process defect monitor data, is presented. The state of the art in IC reliability simulation is advanced in that a methodology that provides the capability to design-in reliability while accounting for early failures has been developed; applications include process qualification, design assessment and fabrication monitoring.

  4. Hidden and Nonstandard Bifurcation Diagram of an Alternate Quadratic System

    NASA Astrophysics Data System (ADS)

    Pastor, G.; Romera, M.; Danca, M.-F.; Martin, A.; Orue, A. B.; Montoya, F.; Encinas, L. Hernández

    Alternate quadratic systems A : xn+1 = 1 - axn2,if n is even 1 - a∗xn2,if n is odd andB : xn+1 = 1 - a∗xn2,if n is even 1 - axn2, if n is odd, where a and a∗ are different parameters, seem to be interval maps in a range of the parameter values. However, after a careful graphical analysis of their bifurcation diagrams we conclude that this is true only for system B, but not for system A. In system A we find a hidden and nonstandard bifurcation diagram (“hidden” because it is not visible at normal resolution and “nonstandard” because the bifurcation diagram is empty for some ranges of the parameter values). The different behavior of the underlying critical polynomial in the range of parameter values in both alternate quadratic systems explains why the hidden and nonstandard bifurcation diagram is present in system A and not in system B. The analysis of the Lyapunov exponent also shows both the existence and the different behavior of the hidden bifurcation diagram of system A.

  5. A Community Based Systems Diagram of Obesity Causes

    PubMed Central

    Allender, Steven; Owen, Brynle; Kuhlberg, Jill; Lowe, Janette; Nagorcka-Smith, Phoebe; Whelan, Jill; Bell, Colin

    2015-01-01

    Introduction Application of system thinking to the development, implementation and evaluation of childhood obesity prevention efforts represents the cutting edge of community-based prevention. We report on an approach to developing a system oriented community perspective on the causes of obesity. Methods Group model building sessions were conducted in a rural Australian community to address increasing childhood obesity. Stakeholders (n = 12) built a community model that progressed from connection circles to causal loop diagrams using scripts from the system dynamics literature. Participants began this work in identifying change over time in causes and effects of childhood obesity within their community. The initial causal loop diagram was then reviewed and elaborated by 50 community leaders over a full day session. Results The process created a causal loop diagram representing community perceptions of determinants and causes of obesity. The causal loop diagram can be broken down into four separate domains; social influences; fast food and junk food; participation in sport; and general physical activity. Discussion This causal loop diagram can provide the basis for community led planning of a prevention response that engages with multiple levels of existing settings and systems. PMID:26153893

  6. [Heart failure: role of cardiovascular imaging].

    PubMed

    Díaz Navarro, Rienzi

    2016-10-11

    The usefulness of echocardiography and the new noninvasive cardiac techniques in assessing heart failure is analyzed. The usefulness of non-invasive CT coronary angiography, as well as the growing applications of magnetic resonance imaging (MRI) in the study of ischemic heart disease, cardiomyopathy and arrhythmogenic right ventricular dysplasia is considered. For this puspose, some clinical cases are used. The combined use of these techniques, especially in patients in whom the etiology of heart failure is ischemic heart disease or cardiomyopathy is emphasized.

  7. Impact of epoetin alfa on left ventricular structure, function, and pressure volume relations as assessed by cardiac magnetic resonance: the heart failure preserved ejection fraction (HFPEF) anemia trial.

    PubMed

    Green, Philip; Babu, Benson A; Teruya, Sergio; Helmke, Stephen; Prince, Martin; Maurer, Mathew S

    2013-01-01

    Anemia, a common comorbidity in older adults with heart failure and a preserved ejection fraction (HFPEF), is associated with worse outcomes. The authors quantified the effect of anemia treatment on left ventricular (LV) structure and function as measured by cardiac magnetic resonance (CMR) imaging. A prospective, randomized single-blind clinical trial (NCT NCT00286182) comparing the safety and efficacy of epoetin alfa vs placebo for 24 weeks in which a subgroup (n=22) had cardiac magnetic resonance imaging (MRI) at baseline and after 3 and 6 months to evaluate changes in cardiac structure and function. Pressure volume (PV) indices were derived from MRI measures of ventricular volume coupled with sphygmomanometer-measured pressure and Doppler estimates of filling pressure. The end-systolic and end-diastolic PV relations and the area between them as a function of end-diastolic pressure, the isovolumic PV area (PVAiso), were calculated. Patients (75±10 years, 64% women) with HFPEF (EF=63%±15%) with an average hemoglobin of 10.3±1.1 gm/dL were treated with epoetin alfa using a dose-adjusted algorithm that increased hemoglobin compared with placebo (P<.0001). As compared with baseline, there were no significant changes in end-diastolic (-7±8 mL vs -3±8 mL, P=.81) or end-systolic (-0.4±2 mL vs -0.7±5 mL, P=.96) volumes at 6-month follow-up between epoetin alfa compared with placebo. LV function as measured based on EF (-1.5%±1.6% vs -2.6%±3.3%, P=.91) and pressure volume indices (PVAiso-EDP at 30 mm Hg, -5071±4308 vs -1662±4140, P=.58) did not differ between epoetin alfa and placebo. Administration of epoetin alfa to older adult patients with HFPEF resulted in a significant increase in hemoglobin, without evident change in LV structure, function, or pressure volume relationships as measured quantitatively using CMR imaging.

  8. [Anaemia in chronic heart failure].

    PubMed

    Hradec, J

    2010-08-01

    Anaemia is a relatively frequent co-morbidity of chronic heart as well as chronic renal failure. In both conditions, it represents a strong and independent predictor of increased morbidity and mortality. Aetiology of this anaemia is multi-factorial. A number of various factors play a role in its development, e.g. inadequate erythropoietin production in the kidneys, bone marrow inhibition, iron deficiency as well as haemodilution associated with fluid retention. Treatment strategies aim at two directions. One is the stimulation of erythropoiesis with recombinant human erythropoietin or its analogues such as darbepoetin alpha. The other involves iron substitution, administered preferably intravenously for improved efficacy and tolerability. Clinical studies evaluating treatment of anaemia in chronic heart failure with erythropoiesis-stimulating agents conducted so far were ofa small scale, were not controlled with placebo and usually assessed proxy parameters. Their results suggested that effective treatment of anaemia in patients with chronic heart failure improves exertion tolerance, clinical status (NYHA class) as well as the quality of life and reduces the need for blood transfusions. Recently completed TREAT study was the first large morbidity and mortality study evaluating treatment of anaemia with an erythropoietin analogue compared to placebo. On a sample of more than 4000 patients with diabetes mellitus, chronic renal failure and significant anaemia, this study has shown that effective treatment of anaemia with darbepoetin alpha did not affect at all the incidence of cardiovascular and renal events; on the other hand, it had lead to a nearly two-fold increase in the incidence of cerebrovascular events. Some doubts about the safety of treatment with erythropoiesis-stimulating agents have occurred in the past based on the studies of anaemia treatment in patients with cancer and renal diseases. An answer to the question whether the treatment of anaemia

  9. How to Draw Energy Level Diagrams in Excitonic Solar Cells.

    PubMed

    Zhu, X-Y

    2014-07-03

    Emerging photovoltaic devices based on molecular and nanomaterials are mostly excitonic in nature. The initial absorption of a photon in these materials creates an exciton that can subsequently dissociate in each material or at their interfaces to give charge carriers. Any attempt at mechanistic understanding of excitonic solar cells must start with drawing energy level diagrams. This seemingly elementary exercise, which is described in textbooks for inorganic solar cells, has turned out to be a difficult subject in the literature. The problem stems from conceptual confusion of single-particle energy with quasi-particle energy and the misleading practice of mixing the two on the same energy level diagram. Here, I discuss how to draw physically accurate energy diagrams in excitonic solar cells using only single-particle energies (ionization potentials and electron affinities) of both ground and optically excited states. I will briefly discuss current understanding on the electronic energy landscape responsible for efficient charge separation in excitonic solar cells.

  10. Fast Formal Analysis of Requirements via "Topoi Diagrams"

    NASA Technical Reports Server (NTRS)

    Menzies, Tim; Powell, John; Houle, Michael E.; Kelly, John C. (Technical Monitor)

    2001-01-01

    Early testing of requirements can decrease the cost of removing errors in software projects. However, unless done carefully, that testing process can significantly add to the cost of requirements analysis. We show here that requirements expressed as topoi diagrams can be built and tested cheaply using our SP2 algorithm, the formal temporal properties of a large class of topoi can be proven very quickly, in time nearly linear in the number of nodes and edges in the diagram. There are two limitations to our approach. Firstly, topoi diagrams cannot express certain complex concepts such as iteration and sub-routine calls. Hence, our approach is more useful for requirements engineering than for traditional model checking domains. Secondly, out approach is better for exploring the temporal occurrence of properties than the temporal ordering of properties. Within these restrictions, we can express a useful range of concepts currently seen in requirements engineering, and a wide range of interesting temporal properties.

  11. Project Management Plan for the INEL technology logic diagrams

    SciTech Connect

    Rudin, M.J.

    1992-10-01

    This Project Management Plan (PjMP) describes the elements of project planning and control that apply to activities outlined in Technical Task Plan (TTP) ID-121117, ``Technology Logic Diagrams For The INEL.`` The work on this project will be conducted by personnel in EG&G Idaho, Inc.`s Waste Technology Development Program. Technology logic diagrams represent a formal methodology to identify technology gaps or needs within Environmental Restoration/Waste Management Operations, which will focus on Office of Environmental Restoration and Waste Management (EM-50) research and development, demonstration, test, and evaluation efforts throughout the US Department of Energy complex. This PjMP describes the objectives, organization, roles and responsibilities, workscope and processes for implementing and managing the technology logic diagram for the Idaho National Engineering Laboratory project.

  12. Project Management Plan for the INEL technology logic diagrams

    SciTech Connect

    Rudin, M.J.

    1992-10-01

    This Project Management Plan (PjMP) describes the elements of project planning and control that apply to activities outlined in Technical Task Plan (TTP) ID-121117, Technology Logic Diagrams For The INEL.'' The work on this project will be conducted by personnel in EG G Idaho, Inc.'s Waste Technology Development Program. Technology logic diagrams represent a formal methodology to identify technology gaps or needs within Environmental Restoration/Waste Management Operations, which will focus on Office of Environmental Restoration and Waste Management (EM-50) research and development, demonstration, test, and evaluation efforts throughout the US Department of Energy complex. This PjMP describes the objectives, organization, roles and responsibilities, workscope and processes for implementing and managing the technology logic diagram for the Idaho National Engineering Laboratory project.

  13. Phase diagrams of low-density polyethylene-alkylbenzene systems

    NASA Astrophysics Data System (ADS)

    Ilyasova, A. N.; Kudryavtsev, Y. V.; Lebedeva, T. N.; Levashova, I. V.; Flyagina, Yu. A.; Pochivalov, K. V.

    2017-03-01

    Complete phase diagrams for mixtures of low-density polyethylene with p- and m-xylene are plotted by optical means in developing the concept of which partially crystalline polymers are microstructured liquids. It is shown that in contrast to the ones presented in the literature, both diagrams contain the solubility boundary curve of the low-molecular weight component in the polymer, above which the polyethylene has the structure of a single-phase gel (crosslinks formed by crystallites and amorphous regions saturated with xylene). At the figurative point on the diagrams, a situation is observed in which the dissolution of all the liquid contained in the initial two-phase system in the polymer is accompanied by its simultaneous complete amorphization. The parameters of the figurative point allow us to estimate the thermodynamic affinity of different alkylbenzenes toward polyethylene.

  14. Monte Carlo study of Dirac semimetals phase diagram

    NASA Astrophysics Data System (ADS)

    Braguta, V. V.; Katsnelson, M. I.; Kotov, A. Yu.; Nikolaev, A. A.

    2016-11-01

    In this paper the phase diagram of Dirac semimetals is studied within a lattice Monte Carlo simulation. In particular, we concentrate on the dynamical chiral symmetry breaking which results in a semimetal-insulator transition. Using numerical simulation, we determine the values of the critical coupling constant of the semimetal-insulator transition for different values of the anisotropy of the Fermi velocity. This measurement allows us to draw a tentative phase diagram for Dirac semimetals. It turns out that within the Dirac model with Coulomb interaction both Na3Bi and Cd3As2 , known experimentally to be Dirac semimetals, would lie deep in the insulating region of the phase diagram. This result probably shows a decisive role of screening of the interelectron interaction in real materials, similar to the situation in graphene.

  15. Generation of Finite Life Distributional Goodman Diagrams for Reliability Prediction

    NASA Technical Reports Server (NTRS)

    Kececioglu, D.; Guerrieri, W. N.

    1971-01-01

    The methodology of developing finite life distributional Goodman diagrams and surfaces is described for presenting allowable combinations of alternating stress and mean stress to the design engineer. The combined stress condition is that of an alternating bending stress and a constant shear stress. The finite life Goodman diagrams and surfaces are created from strength distributions developed at various ratios of alternating to mean stress at particular cycle life values. The conclusions indicate that the Von Mises-Hencky ellipse, for cycle life values above 1000 cycles, is an adequate model of the finite life Goodman diagram. In addition, suggestions are made which reduce the number of experimental data points required in a fatigue data acquisition program.

  16. UML activity diagrams in requirements specification of logic controllers

    NASA Astrophysics Data System (ADS)

    Grobelna, Iwona; Grobelny, Michał

    2015-12-01

    Logic controller specification can be prepared using various techniques. One of them is the wide understandable and user-friendly UML language and its activity diagrams. Using formal methods during the design phase increases the assurance that implemented system meets the project requirements. In the approach we use the model checking technique to formally verify a specification against user-defined behavioral requirements. The properties are usually defined as temporal logic formulas. In the paper we propose to use UML activity diagrams in requirements definition and then to formalize them as temporal logic formulas. As a result, UML activity diagrams can be used both for logic controller specification and for requirements definition, what simplifies the specification and verification process.

  17. Phase diagram studies on the Na-Mo-O system

    NASA Astrophysics Data System (ADS)

    Gnanasekaran, T.; Mahendran, K. H.; Kutty, K. V. G.; Mathews, C. K.

    1989-06-01

    The phase diagram of the Na-Mo-O ternary system is of interest in interpreting the behaviour of structural materials in the sodium circuits of fast breeder reactors and sodium-filled heat pipes. Experiments involving heating of sodium oxide with molybdenum metal under vacuum, selective removal of oxygen from polymolybdates by reducing them under hydrogen and confirmation of the coexistence of various phase mixtures were conducted in the temperature range of 673 to 923 K. Phase fields involving molybdenum metal, dioxide of molybdenum and ternary compounds were derived from these results. The ternary phase diagram of the Na-Mo-O system was constructed and isothermal cross sections of the phase diagram are presented.

  18. Pressure-Temperature Phase Diagram of Vanadium Dioxide.

    PubMed

    Chen, Yabin; Zhang, Shuai; Ke, Feng; Ko, Changhyun; Lee, Sangwook; Liu, Kai; Chen, Bin; Ager, Joel W; Jeanloz, Raymond; Eyert, Volker; Wu, Junqiao

    2017-03-08

    The complexity of strongly correlated electron physics in vanadium dioxide is exemplified as its rich phase diagrams of all kinds, which in turn shed light on the mechanisms behind its various phase transitions. In this work, we map out the hydrostatic pressure-temperature phase diagram of vanadium dioxide nanobeams by independently varying pressure and temperature with a diamond anvil cell. In addition to the well-known insulating M1 (monoclinic) and metallic R (tetragonal) phases, the diagram identifies the existence at high pressures of the insulating M1' (monoclinic, more conductive than M1) phase and two metallic phases of X (monoclinic) and O (orthorhombic, at high temperature only). Systematic optical and electrical measurements combined with density functional calculations allow us to delineate their phase boundaries as well as reveal some basic features of the transitions.

  19. On the Disposition of Maunders' Origninal Butterfly Diagram

    NASA Astrophysics Data System (ADS)

    Bogdan, T. J.

    2000-05-01

    On 21 May 1940, Annie S. D. Maunder mailed the original drawing of the celebrated ``Maunder Butterfly Diagram" to Stephen A., and his daughter Margaret L., Ionides. Later that same year Stephen and Margaret gave the diagram ``on indefinite loan" to Walter Orr Roberts, then the Superintendent of Fremont Pass Station of the Harvard College Observatory. The framed diagram remains on display today at the scion of that organization, the High Altitude Observatory of the National Center for Atmospheric Research, in Boulder Colorado. Drawing upon the original correspondences, this contribution recounts the story behind the travels of the ``Maunder Butterfly" during the second World War. The National Center for Atmospheric Research is sponsored by the National Science Foundation.

  20. Living with Respiratory Failure

    MedlinePlus

    ... smoking. Emotional Issues and Support Living with respiratory failure may cause fear, anxiety, depression, and stress. Talk about how you feel with your health care team. Talking to a professional counselor also can ... to living with respiratory failure. You can see how other people who have ...

  1. Ampoule Failure System

    NASA Technical Reports Server (NTRS)

    Watring, Dale A. (Inventor); Johnson, Martin L. (Inventor)

    1996-01-01

    An ampoule failure system for use in material processing furnaces comprising a containment cartridge and an ampoule failure sensor. The containment cartridge contains an ampoule of toxic material therein and is positioned within a furnace for processing. An ampoule failure probe is positioned in the containment cartridge adjacent the ampoule for detecting a potential harmful release of toxic material therefrom during processing. The failure probe is spaced a predetermined distance from the ampoule and is chemically chosen so as to undergo a timely chemical reaction with the toxic material upon the harmful release thereof. The ampoule failure system further comprises a data acquisition system which is positioned externally of the furnace and is electrically connected to the ampoule failure probe so as to form a communicating electrical circuit. The data acquisition system includes an automatic shutdown device for shutting down the furnace upon the harmful release of toxic material. It also includes a resistance measuring device for measuring the resistance of the failure probe during processing. The chemical reaction causes a step increase in resistance of the failure probe whereupon the automatic shutdown device will responsively shut down the furnace.

  2. Asymptotic analysis of Bayesian generalization error with Newton diagram.

    PubMed

    Yamazaki, Keisuke; Aoyagi, Miki; Watanabe, Sumio

    2010-01-01

    Statistical learning machines that have singularities in the parameter space, such as hidden Markov models, Bayesian networks, and neural networks, are widely used in the field of information engineering. Singularities in the parameter space determine the accuracy of estimation in the Bayesian scenario. The Newton diagram in algebraic geometry is recognized as an effective method by which to investigate a singularity. The present paper proposes a new technique to plug the diagram in the Bayesian analysis. The proposed technique allows the generalization error to be clarified and provides a foundation for an efficient model selection. We apply the proposed technique to mixtures of binomial distributions.

  3. Theoretical phase diagrams for solid H{sub 2}

    SciTech Connect

    Surh, M.P.; Runge, K.J.

    1993-07-01

    Possible phase diagrams for solid molecular para-hydrogen in the 0-200 GPa pressure regime are constructed on the basis of ab initio calculations. Structures for the broken symmetry phase (BSP) and H-A phase have recently been proposed under the assumption that the molecules are centered on sites of a hexagonal close-packed lattice with the ideal c/a ratio, i.e., only molecular orientational and electronic changes are allowed. Symmetry considerations then dictate the simplest phase diagrams consistent with experimental observations, although the possibility of additional transitions cannot be ruled out. A simple model is introduced to describe the BSP and H-A transitions.

  4. Strain-Temperature-Transformation (STT) Diagram for Soft Solids

    NASA Astrophysics Data System (ADS)

    Li, Shoubo; Xiong, Wentao; Wang, Xiaorong

    Soft materials comprise a variety of physical states that are easily deformed by shear stains or thermal fluctuations. They include suspensions, colloids, polymers, foams, gels, liquid crystals, and a number of biological materials. In this contribution, a generalized strain-temperature-transformation (STT) diagram for many soft materials is presented in which the physical states encountered are related to the strain and temperature changes. The boundary defined for the solid-to-liquid transformation in the STT diagram displays a surprising Z-shaped curve. We discuss this feature with respect to the physical nature of materials.

  5. GPU based detection of topological changes in Voronoi diagrams

    NASA Astrophysics Data System (ADS)

    Bernaschi, M.; Lulli, M.; Sbragaglia, M.

    2017-04-01

    The Voronoi diagrams are an important tool having theoretical and practical applications in a large number of fields. We present a new procedure, implemented as a set of CUDA kernels, which detects, in a general and efficient way, topological changes in case of dynamic Voronoi diagrams whose generating points move in time. The solution that we provide has been originally developed to identify plastic events during simulations of soft-glassy materials based on a lattice Boltzmann model with frustrated-short range attractive and mid/long-range repulsive-interactions. Along with the description of our approach, we present also some preliminary physics results.

  6. UML activity diagram swimlanes in logic controller design

    NASA Astrophysics Data System (ADS)

    Grobelny, Michał; Grobelna, Iwona

    2015-12-01

    Logic controller behavior can be specified using various techniques, including UML activity diagrams and control Petri nets. Each technique has its advantages and disadvantages. Application of both specification types in one project allows to take benefits from both of them. Additional elements of UML models make it possible to divide a specification into some parts, considered from other point of view (logic controller, user or system). The paper introduces an idea to use UML activity diagrams with swimlanes to increase the understandability of design models.

  7. Resistance of Feynman diagrams and the percolation backbone dimension.

    PubMed

    Janssen, H K; Stenull, O; Oerding, K

    1999-06-01

    We present an alternative view of Feynman diagrams for the field theory of random resistor networks, in which the diagrams are interpreted as being resistor networks themselves. This simplifies the field theory considerably as we demonstrate by calculating the fractal dimension D(B) of the percolation backbone to three loop order. Using renormalization group methods we obtain D(B)=2+epsilon/21-172epsilon(2)/9261+2epsilon(3)[-74 639+22 680zeta(3)]/4 084 101, where epsilon=6-d with d being the spatial dimension and zeta(3)=1.202 057... .

  8. Generalized energy failure criterion.

    PubMed

    Qu, R T; Zhang, Z J; Zhang, P; Liu, Z Q; Zhang, Z F

    2016-03-21

    Discovering a generalized criterion that can predict the mechanical failure of various different structural materials is one of ultimate goals for scientists in both material and mechanics communities. Since the first study on the failure criterion of materials by Galileo, about three centuries have passed. Now we eventually find the "generalized energy criterion", as presented here, which appears to be one universal law for various different kinds of materials. The validity of the energy criterion for quantitatively predicting the failure is experimentally confirmed using a metallic glass. The generalized energy criterion reveals the competition and interaction between shear and cleavage, the two fundamental inherent failure mechanisms, and thus provides new physical insights into the failure prediction of materials and structural components.

  9. Acute Decompensated Heart Failure

    PubMed Central

    Joseph, Susan M.; Cedars, Ari M.; Ewald, Gregory A.; Geltman, Edward M.; Mann, Douglas L.

    2009-01-01

    Hospitalizations for acute decompensated heart failure are increasing in the United States. Moreover, the prevalence of heart failure is increasing consequent to an increased number of older individuals, as well as to improvement in therapies for coronary artery disease and sudden cardiac death that have enabled patients to live longer with cardiovascular disease. The main treatment goals in the hospitalized patient with heart failure are to restore euvolemia and to minimize adverse events. Common in-hospital treatments include intravenous diuretics, vasodilators, and inotropic agents. Novel pharmaceutical agents have shown promise in the treatment of acute decompensated heart failure and may simplify the treatment and reduce the morbidity associated with the disease. This review summarizes the contemporary management of patients with acute decompensated heart failure. PMID:20069075

  10. Generalized energy failure criterion

    PubMed Central

    Qu, R. T.; Zhang, Z. J.; Zhang, P.; Liu, Z. Q.; Zhang, Z. F.

    2016-01-01

    Discovering a generalized criterion that can predict the mechanical failure of various different structural materials is one of ultimate goals for scientists in both material and mechanics communities. Since the first study on the failure criterion of materials by Galileo, about three centuries have passed. Now we eventually find the “generalized energy criterion”, as presented here, which appears to be one universal law for various different kinds of materials. The validity of the energy criterion for quantitatively predicting the failure is experimentally confirmed using a metallic glass. The generalized energy criterion reveals the competition and interaction between shear and cleavage, the two fundamental inherent failure mechanisms, and thus provides new physical insights into the failure prediction of materials and structural components. PMID:26996781

  11. TIME-TEMPERATURE-TRANSFORMATION DIAGRAMS FOR THE SLUDGE BATCH 3 - FRIT 418 GLASS SYSTEM

    SciTech Connect

    Billings, A; Tommy Edwards, T

    2009-03-03

    As a part of the Waste Acceptance Product Specifications (WAPS) for Vitrified High-Level Waste Forms defined by the Department of Energy - Office of Environmental Management, the phase stability must be determined for each of the projected high-level waste (HLW) types at the Savannah River Site (SRS). Specifically, WAPS 1.4.1 requires the glass transition temperature (Tg) to be defined and time-temperature-transformation (TTT) diagrams to be developed. The Tg of a glass is an indicator of the approximate temperature where the supercooled liquid converts to a solid on cooling or conversely, where the solid begins to behave as a viscoelastic solid on heating. A TTT diagram identifies the crystalline phases that can form as a function of time and temperature for a given waste type or more specifically, the borosilicate glass waste form. In order to assess durability, the Product Consistency Test (PCT) was used and the durability results compared to the Environmental Assessment (EA) glass. The measurement of glass transition temperature and the development of TTT diagrams have already been performed for the seven Defense Waste Processing Facility (DWPF) projected compositions as defined in the Waste Form Compliance Plan (WCP). These measurements were performed before DWPF start-up and the results were incorporated in Volume 7 of the Waste Form Qualification Report (WQR). Additional information exists for other projected compositions, but overall these compositions did not consider some of the processing scenarios now envisioned for DWPF to accelerate throughput. Changes in DWPF processing strategy have required this WAPS specification to be revisited to ensure that the resulting phases have been bounded. Frit 418 was primarily used to process HLW Sludge Batch 3 (SB3) at 38% waste loading (WL) through the DWPF. The Savannah River National Laboratory (SRNL) fabricated a cache of glass from reagent grade oxides to simulate the SB3-Frit 418 system at a 38 wt % WL for glass

  12. Assessment.

    ERIC Educational Resources Information Center

    Reising, Bob

    1998-01-01

    Argues (guided by "The Challenge of Change: Assessment in the 21st Century") that in the decades ahead, assessment will play an unprecedented role as the vehicle that will influence and guide scheduling, curriculum, and instruction. (SR)

  13. Handheld Capillary Blood Lactate Analyzer as an Accessible and Cost-Effective Prognostic Tool for the Assessment of Death and Heart Failure Occurrence during Long-Term Follow-Up

    PubMed Central

    Jacheć, Wojciech; Traczewska, Magdalena; Kolaszko, Agnieszka; Kubiak, Leszek; Jojko, Joanna; Nowalany-Kozielska, Ewa

    2016-01-01

    Impact of tissue lactate accumulation on prognosis after acute myocardial infarction (AMI) is biased. The study aimed to assess the prognostic role of lactate concentration (LC) in patients with AMI during one year of follow-up. 145 consecutive patients admitted due to AMI were enrolled. The data on the frequency of endpoint occurrence (defined as I, death; II, heart failure (HF); and III, recurrent myocardial infarction (re-MI)) were collected. The patients were divided into group A (LC below the cut-off value) and group B (LC above the cut-off value) for the endpoints according to receiver operating characteristic (ROC) analysis. The cumulative survival rate was 99% in group I-A and 85% in group I-B (p = 0.0004, log-rank test). The HF-free survival rate was 95% in group II-A and 82% in group II-B (p = 0.0095, log-rank test). The re-MI-free survival rate did not differ between groups. A multivariate Cox analysis showed a statistically significant influence of LC on death [Hazard Ratio (HR): 1.41, 95% Confidence Interval (CI) (1.13–1.76), and p = 0.002] and HF [HR: 1.21, 95% CI (1.05–1.4), and p = 0.007] with no impact on re-MI occurrence. LC in capillary blood may be considered a useful prognostic marker of late-onset heart failure and death after AMI. PMID:28115788

  14. Revision of the geological context of the Port-au-Prince metropolitan area, Haiti: implications for slope failures and seismic hazard assessment

    NASA Astrophysics Data System (ADS)

    Terrier, M.; Bialkowski, A.; Nachbaur, A.; Prépetit, C.; Joseph, Y. F.

    2014-09-01

    Following the earthquake of 12 January 2010 in the Port-au-Prince area, the Haitian government, in close cooperation with BRGM, the French geological Survey, decided to undertake a seismic microzonation study of the metropolitan area of the capital in order to take more fully into account the seismic risk in the urbanization and planning of the city under reconstruction. As the first step of the microzonation project, a geological study has been carried out. Deposits of Miocene and Pliocene formations in a marine environment have been identified. These deposits are affected by the Enriquillo-Plantain Garden N80° E fault system and N110° E faults. Tectonic observations and morphological analysis indicate Quaternary activity of several faults mapped in the area of Port-au-Prince. These faults have a N110° trend and show a reverse-sinistral strike-slip motion. Moreover, on the basis of these geological results and of new topographical data, a hazard assessment of ground movements has been made. Along with the map of active faults, the hazard map of ground movements is an integral component of the seismic microzonation study.

  15. Synergistic failure of BWR internals

    SciTech Connect

    A. G. Ware; T. Y. Chang

    1999-10-25

    Boiling Water Reactor (BWR) core shrouds and other reactor internals important to safety are experiencing intergranular stress corrosion cracking (IGSCC). The United States Nuclear Regulatory Commission has followed the problem, and as part of its investigations, contracted with the Idaho National Engineering and Environmental Laboratory to conduct a risk assessment. The overall project objective is to assess the potential consequences and risks associated with the failure of IGSCC-susceptible BWR vessel internals, with specific consideration given to potential cascading and common mode effects. An initial phase has been completed in which background material was gathered and evaluated, and potential accident sequences were identified. A second phase is underway to perform a simplified, quantitative probabilistic risk assessment on a representative high-power BWR/4. Results of the initial study conducted on the jet pumps show that any cascading failures would not result in a significant increase in the core damage frequency. The methodology is currently being extended to other major reactor internals components.

  16. Synergistic Failure of BWR Internals

    SciTech Connect

    Ware, Arthur Gates; Chang, T-Y

    1999-10-01

    Boiling Water Reactor (BWR) core shrouds and other reactor internals important to safety are experiencing intergranular stress corrosion cracking (IGSCC). The United States Nuclear Regulatory Commission has followed the problem, and as part of its investigations, contracted with the Idaho National Engineering and Environmental Laboratory to conduct a risk assessment. The overall project objective is to assess the potential consequences and risks associated with the failure of IGSCC-susceptible BWR vessel internals, with specific consideration given to potential cascading and common mode effects. An initial phase has been completed in which background material was gathered and evaluated, and potential accident sequences were identified. A second phase is underway to perform a simplified, quantitative probabilistic risk assessment on a representative high-power BWR/4. Results of the initial study conducted on the jet pumps show that any cascading failures would not result in a significant increase in the core damage frequency. The methodology is currently being extended to other major reactor internals components.

  17. Analysing Collisions Using Minkowski Diagrams in Momentum Space

    ERIC Educational Resources Information Center

    Bokor, Nandor

    2011-01-01

    Momentum space and Minkowski diagrams are powerful tools for interpreting and analysing relativistic collisions in one or two spatial dimensions. All relevant quantities that characterize a collision, including the mass, velocity, momentum and energy of the interacting particles, both before and after collision, can be directly seen from a single…

  18. Sun Shading Diagrams for School Buildings. Educational Building Report 2.

    ERIC Educational Resources Information Center

    Mooij, D.

    This publication provides data on the angles governing the design of sunshading devices for educational buildings in the countries of the Asian region and gives examples of the ways in which these data can be used. Different methods of excluding direct sunlight from teaching spaces are illustrated in a series of diagrams that show exclusion by…

  19. Using Nuclear Magnetic Resonance Spectroscopy for Measuring Ternary Phase Diagrams

    ERIC Educational Resources Information Center

    Woodworth, Jennifer K.; Terrance, Jacob C.; Hoffmann, Markus M.

    2006-01-01

    A laboratory experiment is presented for the upper-level undergraduate physical chemistry curriculum in which the ternary phase diagram of water, 1-propanol and n-heptane is measured using proton nuclear magnetic resonance (NMR) spectroscopy. The experiment builds upon basic concepts of NMR spectral analysis, typically taught in the undergraduate…

  20. Dynamical phase diagram of Gaussian wave packets in optical lattices

    NASA Astrophysics Data System (ADS)

    Hennig, H.; Neff, T.; Fleischmann, R.

    2016-03-01

    We study the dynamics of self-trapping in Bose-Einstein condensates (BECs) loaded in deep optical lattices with Gaussian initial conditions, when the dynamics is well described by the discrete nonlinear Schrödinger equation (DNLSE). In the literature an approximate dynamical phase diagram based on a variational approach was introduced to distinguish different dynamical regimes: diffusion, self-trapping, and moving breathers. However, we find that the actual DNLSE dynamics shows a completely different diagram than the variational prediction. We calculate numerically a detailed dynamical phase diagram accurately describing the different dynamical regimes. It exhibits a complex structure that can readily be tested in current experiments in BECs in optical lattices and in optical waveguide arrays. Moreover, we derive an explicit theoretical estimate for the transition to self-trapping in excellent agreement with our numerical findings, which may be a valuable guide as well for future studies on a quantum dynamical phase diagram based on the Bose-Hubbard Hamiltonian.