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Sample records for fatigue evaluation methodology

  1. A methodology to evaluate the fatigue life of flexible pipes

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, Fernando J.M. de; Sousa, Jose Renato M. de; Siqueira, Marcos Q. de; Sagrilo, Luis V.S. [Coordenacao dos Programas de Pos-graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil); Lemos, Carlos Alberto D. de [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2009-07-01

    This paper focus on a methodology to perform the fatigue analysis of flexible pipes. This methodology employs functions that convert forces and moments obtained in global analyses into stresses. The stresses are then processed by well-known cycle counting methods, and S-N curves evaluate the damage at several points in the pipe cross-section. Palmgren-Miner linear damage hypothesis is assumed in order to calculate the accumulated fatigue damage. A parametric study on the fatigue life of a flexible pipe employing this methodology is presented. The main points addressed in the study are the influence of friction between layers in the results, the importance of evaluating the fatigue life in various points of the pipe cross-section and the effect of different mean stress levels. The obtained results suggest that the consideration of friction effects strongly influences the fatigue life of flexible risers and these effects have to be accounted both in the global and local analyses of the riser. Moreover, mean stress effects are also significant and at least 8 equally spaced wires in each analyzed section of the riser must be considered in fatigue analyses. (author)

  2. Fatigue Evaluation Algorithms: Review

    DEFF Research Database (Denmark)

    Passipoularidis, Vaggelis; Brøndsted, Povl

    series can be simulated. The predictions are validated against fatigue life data both from repeated block tests at a single stress ratio as well as against spectral fatigue using the WISPER, WISPERX and NEW WISPER load sequences on a Glass/Epoxy multidirectional laminate typical of a wind turbine rotor...

  3. Fatigue evaluation algorithms: Review

    Energy Technology Data Exchange (ETDEWEB)

    Passipoularidis, V.A.; Broendsted, P.

    2009-11-15

    A progressive damage fatigue simulator for variable amplitude loads named FADAS is discussed in this work. FADAS (Fatigue Damage Simulator) performs ply by ply stress analysis using classical lamination theory and implements adequate stiffness discount tactics based on the failure criterion of Puck, to model the degradation caused by failure events in ply level. Residual strength is incorporated as fatigue damage accumulation metric. Once the typical fatigue and static properties of the constitutive ply are determined,the performance of an arbitrary lay-up under uniaxial and/or multiaxial load time series can be simulated. The predictions are validated against fatigue life data both from repeated block tests at a single stress ratio as well as against spectral fatigue using the WISPER, WISPERX and NEW WISPER load sequences on a Glass/Epoxy multidirectional laminate typical of a wind turbine rotor blade construction. Two versions of the algorithm, the one using single-step and the other using incremental application of each load cycle (in case of ply failure) are implemented and compared. Simulation results confirm the ability of the algorithm to take into account load sequence effects. In general, FADAS performs well in predicting life under both spectral and block loading fatigue. (author)

  4. A methodology for strain-based fatigue reliability analysis

    International Nuclear Information System (INIS)

    Zhao, Y.X.

    2000-01-01

    A significant scatter of the cyclic stress-strain (CSS) responses should be noted for a nuclear reactor material, 1Cr18Ni9Ti pipe-weld metal. Existence of the scatter implies that a random cyclic strain applied history will be introduced under any of the loading modes even a deterministic loading history. A non-conservative evaluation might be given in the practice without considering the scatter. A methodology for strain-based fatigue reliability analysis, which has taken into account the scatter, is developed. The responses are approximately modeled by probability-based CSS curves of Ramberg-Osgood relation. The strain-life data are modeled, similarly, by probability-based strain-life curves of Coffin-Manson law. The reliability assessment is constructed by considering interference of the random fatigue strain applied and capacity histories. Probability density functions of the applied and capacity histories are analytically given. The methodology could be conveniently extrapolated to the case of deterministic CSS relation as the existent methods did. Non-conservative evaluation of the deterministic CSS relation and availability of present methodology have been indicated by an analysis of the material test results

  5. Probabilistic fatigue life prediction methodology for notched components based on simple smooth fatigue tests

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Z. R.; Li, Z. X. [Dept.of Engineering Mechanics, Jiangsu Key Laboratory of Engineering Mechanics, Southeast University, Nanjing (China); Hu, X. T.; Xin, P. P.; Song, Y. D. [State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, Nanjing (China)

    2017-01-15

    The methodology of probabilistic fatigue life prediction for notched components based on smooth specimens is presented. Weakestlink theory incorporating Walker strain model has been utilized in this approach. The effects of stress ratio and stress gradient have been considered. Weibull distribution and median rank estimator are used to describe fatigue statistics. Fatigue tests under different stress ratios were conducted on smooth and notched specimens of titanium alloy TC-1-1. The proposed procedures were checked against the test data of TC-1-1 notched specimens. Prediction results of 50 % survival rate are all within a factor of two scatter band of the test results.

  6. Noncontact fatigue crack evaluation using thermoelastic

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Min; An, Yun Kyu; Sohn, Hoon [KAIST, Daejeon (Korea, Republic of)

    2012-12-15

    This paper proposes a noncontact thermography technique for fatigue crack evaluation under a cyclic tensile loading. The proposed technique identifies and localizes an invisible fatigue crack without scanning, thus making it possible to instantaneously evaluate an incipient fatigue crack. Based on a thermoelastic theory, a new fatigue crack evaluation algorithm is proposed for the fatigue crack tip localization. The performance of the proposed algorithm is experimentally validated. To achieve this, the cyclic tensile loading is applied to a dog bone shape aluminum specimen using a universal testing machine, and the corresponding thermal responses induced by thermoelastic effects are captured by an infrared camera. The test results confirm that the fatigue crack is well identified and localized by comparing with its microscopic images.

  7. Areva fatigue concept. Fast fatigue evaluation, a new method for fatigue analysis

    International Nuclear Information System (INIS)

    Heinz, Benedikt; Bergholz, Steffen; Rudolph, Juergen

    2011-01-01

    Within the discussions on the long term operation (LTO) of nuclear power plants the ageing management is on the focus of that analysis. The knowledge of the operational thermal cyclic load data on components of the power plants and their evaluation in the fatigue analysis is a central concern. The changes in fatigue requirements (e.g. the consideration of environmentally assisted fatigue - EAF) recently discussed and LTO efforts are a strong motivation for the identification of margins in the existing fatigue analysis approaches. These margins should be considered within new approaches in order to obtain realistic (or more accurate) analysis results. Of course, these new analysis approaches have to be manageable and efficient. The Areva Fatigue Concept (AFC) offers the comprehensive conceptual basis for the consideration of fatigue on different levels and depths. The combination of data logging and automated fatigue evaluation are important modules of the AFC. Besides the established simplified stress based fatigue estimation Areva develops a further automated fatigue analysis method called Fast Fatigue Evaluation (FFE). This method comprises highly automated stress analyses at the fatigue relevant locations of the component. Hence, a component specific course of stress as a function of time is determined based on FAMOS or similar temperature measurement systems. The subsequent application of the rain flow cycle counting algorithm allows for the determination of the usage factor following the rules of the design code requirements. The new FFE approach constitutes a cycle counting method based on the real stresses in the component, and determined as result a rule-conformity cumulative usage factor. (orig.)

  8. Fatigue evaluation in reactor vessel components

    International Nuclear Information System (INIS)

    Mattar Neto, Miguel; Miranda, Carlos A. de J.

    1994-01-01

    This paper presents a sequence of increasing complexity forms of evaluating fatigue damage of nuclear pressure vessel components caused by cycling loadings. Examples are included in order to illustrate such procedures. (author)

  9. Fatigue data compilation and evaluation of fatigue on design

    International Nuclear Information System (INIS)

    Nyilas, A.

    1985-05-01

    The aim of this report is a review of the available fatigue data of various materials necessary for the design of large superconducting magnets for fusion. One of the primary objectives of this work is to present a broad outline of the low temperature fatigue data of relevant materials within the scope of available data. Besides the classical fatigue data of materials the fatigue crack propagation measurements are outlined widely. The existing recommendations for the design of cryogenic structures are described. A brief introduction of fracture mechanics as well as a historical background of the development of our present day understanding of fatigue has been done. (orig.) [de

  10. Thermal fatigue evaluation of partially cooled pipes

    International Nuclear Information System (INIS)

    Kawasaki, N.; Kasahara, N.; Takasho, H.

    2004-01-01

    Concerning thermal striping phenomenon with a cold/hot spot, effect of the thermal spot on fatigue strength was investigated. The thermal spot causes membrane stress and enhances bending stress in the structure. Increased stress shortens the fatigue life and accelerates the crack propagation rate. The mechanism to increase stress was found to be the structural constraint of thermal strain by the thermal spot. To consider this mechanism, constraint efficiency factors were introduced to the thermal stress evaluation method based on frequency transfer functions developed by authors. Proposed method with these factors was validated through comparisons with cyclic FEA considering thermal spots. (orig.)

  11. Reduction in alert fatigue in an assisted electronic prescribing system, through the Lean Six Sigma methodology.

    Science.gov (United States)

    Cuéllar Monreal, Mª Jesús; Reig Aguado, Jorge; Font Noguera, Isabel; Poveda Andrés, José Luis

    2017-01-01

    To reduce the alert fatigue in our Assisted Electronic Prescribing System (AEPS), through the Lean Six Sigma (LSS) methodology. An observational (transversal) and retrospective study, in a general hospital with 850 beds and AEPS. The LSS methodology was followed in order to evaluate the alert fatigue situation in the AEPS system, to implement improvements, and to assess outcomes. The alerts generated during two trimesters studied (before and after the intervention) were analyzed. In order to measure the qualitative indicators, the most frequent alert types were analyzed, as well as the molecules responsible for over 50% of each type of alert. The action by the prescriber was analyzed in a sample of 496 prescriptions that generated such alerts. For each type of alert and molecule, there was a prioritization of the improvements to be implemented according to the alert generated and its quality. A second survey evaluated the pharmacist action for the alerts most highly valued by physicians. The problem, the objective, the work team and the project schedule were defined. A survey was designed in order to understand the opinion of the client about the alert system in the program. Based on the surveys collected (n = 136), the critical characteristics and the quanti/qualitative indicators were defined. Sixty (60) fields in the alert system were modified, corresponding to 32 molecules, and this led to a 28% reduction in the total number of alerts. Regarding quality indicators, false po sitive results were reduced by 25% (p < 0.05), 100% of those alerts ignored with justification were sustained, and there were no significant differences in user adherence to the system. The project improvements and outcomes were reviewed by the work team. LSS methodology has demonstrated being a valid tool for the quantitative and qualitative improvement of the alert system in an Assisted Electronic Prescription Program, thus reducing alert fatigue. Copyright AULA MEDICA EDICIONES 2014

  12. Personality and chronic fatigue syndrome: methodological and conceptual issues.

    Science.gov (United States)

    van Geelen, Stefan M; Sinnema, Gerben; Hermans, Hubert J M; Kuis, Wietse

    2007-12-01

    Among clinical psychologists, consulting physicians, scientific researchers and society in general an image has emerged of patients with chronic fatigue syndrome (CFS) as perfectionist, conscientious, hardworking, somewhat neurotic and introverted individuals with high personal standards, a great desire to be socially accepted and with a history of continuously pushing themselves past their limits. The aim of this article is to (a) give a concise review of the main recent studies on personality and CFS, (b) address the major methodological problems in the study of personality in CFS and (c) discuss some of the conceptual assumptions that seem to limit the research on personality and CFS. The results of the reviewed studies range from no evidence of major differences between the personalities of patients with CFS and controls, to evidence of severe psychopathology and personality disorder in patients with CFS. Although personality seems to play a role in CFS, it is difficult to draw general conclusions on the relation between personality and CFS. It is argued that this is partially due to the diversity and heterogeneity in study methods, patient populations, control groups and CFS case definitions. Personality should be regarded as an important factor to be studied in CFS. However, additional studies are needed, not focusing exclusively on personality disorder, or personality considered on a general trait level. In recent developments in personality research, the continually evolving life narrative that makes sense of, and gives direction to, an individual's life is also regarded as an important aspect of personality. New insights into personality and CFS might be gained by systematically studying the self-narratives of patients with the syndrome.

  13. Neuromuscular fatigue during exercise: Methodological considerations, etiology and potential role in chronic fatigue.

    Science.gov (United States)

    Twomey, Rosie; Aboodarda, Saied Jalal; Kruger, Renata; Culos-Reed, Susan Nicole; Temesi, John; Millet, Guillaume Y

    2017-04-01

    The term fatigue is used to describe a distressing and persistent symptom of physical and/or mental tiredness in certain clinical populations, with distinct but ultimately complex, multifactorial and heterogenous pathophysiology. Chronic fatigue impacts on quality of life, reduces the capacity to perform activities of daily living, and is typically measured using subjective self-report tools. Fatigue also refers to an acute reduction in the ability to produce maximal force or power due to exercise. The classical measurement of exercise-induced fatigue involves neuromuscular assessments before and after a fatiguing task. The limitations and alternatives to this approach are reviewed in this paper in relation to the lower limb and whole-body exercise, given the functional relevance to locomotion, rehabilitation and activities of daily living. It is suggested that under some circumstances, alterations in the central and/or peripheral mechanisms of fatigue during exercise may be related to the sensations of chronic fatigue. As such, the neurophysiological correlates of exercise-induced fatigue are briefly examined in two clinical examples where chronic fatigue is common: cancer survivors and people with multiple sclerosis. This review highlights the relationship between objective measures of fatigability with whole-body exercise and perceptions of fatigue as a priority for future research, given the importance of exercise in relieving symptoms of chronic fatigue and/or overall disease management. As chronic fatigue is likely to be specific to the individual and unlikely to be due to a simple biological or psychosocial explanation, tailored exercise programmes are a potential target for therapeutic intervention. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  14. Screening Risk Evaluation methodology

    International Nuclear Information System (INIS)

    Hopper, K.M.

    1994-01-01

    The Screening Risk Evaluation (SRE) Guidance document is a set of guidelines provided for the uniform implementation of SREs performed on D ampersand D facilities. These guidelines are designed specifically for the completion of the second (semi-quantitative screening) phase of the D ampersand D Risk-Based Process. The SRE Guidance produces screening risk scores reflecting levels of risk through the use of risk ranking indices. Five types of possible risk are calculated from the SRE: current releases, worker exposures, future releases, physical hazards, and criticality. The Current Release Index (CRI) calculates the risk to human health and the environment from ongoing or probable releases within a one year time period. The Worker Exposure Index (WEI) calculates the risk to workers, occupants, and visitors in D ampersand D facilities of contaminant exposure. The Future Release Index (FRI) calculates the risk of future releases of contaminants, after one year, to human health and the environment. The Physical Hazards Index (PHI) calculates the risk-to human health due to factors other than that of contaminants. The index of Criticality is approached as a modifying factor to the entire SRE, due to the fact that criticality issues are strictly regulated under DOE. Screening risk results will be tabulated in matrix form and Total Risk will be calculated (weighted equation) to produce a score on which to base early action recommendations. Other recommendations from the screening risk scores will be made based either on individual index scores or from reweighted Total Risk calculations. All recommendations based on the SRE will be made based on a combination of screening risk scores, decision drivers, and other considerations, determined on a project by project basis. The SRE is the first and most important step in the overall D ampersand D project level decision making process

  15. Systematic Review Methodology for the Fatigue in Emergency Medical Services Project.

    Science.gov (United States)

    Patterson, P Daniel; Higgins, J Stephen; Weiss, Patricia M; Lang, Eddy; Martin-Gill, Christian

    2018-02-15

    Guidance for managing fatigue in the Emergency Medical Services (EMS) setting is limited. The Fatigue in EMS Project sought to complete multiple systematic reviews guided by seven explicit research questions, assemble the best available evidence, and rate the quality of that evidence for purposes of producing an Evidence Based Guideline (EBG) for fatigue risk management in EMS operations. We completed seven systematic reviews that involved searches of six databases for literature relevant to seven research questions. These questions were developed a priori by an expert panel and framed in the Population, Intervention, Comparison, and Outcome (PICO) format and pre-registered with PROSPERO. Our target population was defined as persons 18 years of age and older classified as EMS personnel or similar shift worker groups. A panel of experts selected outcomes for each PICO question as prescribed by the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. We pooled findings, stratified by study design (experimental vs. observational) and presented results of each systematic review in narrative and quantitative form. We used meta-analyses of select outcomes to generate pooled effects. We used the GRADE methodology and the GRADEpro software to designate a quality of evidence rating for each outcome. We present the results for each systematic review in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA). More than 38,000 records were screened across seven systematic reviews. The median, minimum, and maximum inter-rater agreements (Kappa) between screeners for our seven systematic reviews were 0.66, 0.49, and 0.88, respectively. The median, minimum, and maximum number of records retained for the seven systematic reviews was 13, 1, and 100, respectively. We present key findings in GRADE Evidence Profile Tables in separate publications for each systematic review. We describe a protocol for

  16. Evaluation of micro fatigue crack growth under equi-biaxial stress by membranous pressure fatigue test

    International Nuclear Information System (INIS)

    Iida, Satoshi; Abe, Shigeki; Nakamura, Takao; Kamaya, Masayuki

    2014-01-01

    For preventing nuclear power plant (NPP) accidents, NPPs are required to ensure system safety in long term safe operation under aging degradation. Now, fatigue accumulation is one of major ageing phenomena and are evaluated to ensure safety by design fatigue curve that are based on the results of uniaxial fatigue tests. On the other hand, thermal stress that occurs in piping of actual components is not uniaxial but equi-biaxial. For accurate evaluation, it is required to conform real circumstance. In this study, membranous pressure fatigue test was conducted to simulated equi-biaxial stress. Crack initiation and crack growth were examined by replica investigation. Calculation result of equivalent stress intensity factor shows crack growth under equi-biaxial stress is faster than under uniaxial stress. It is concluded that equi-biaxial fatigue behavior should be considered in the evaluation of fatigue crack initiation and crack growth. (author)

  17. Inventory differences: An evaluation methodology

    International Nuclear Information System (INIS)

    Heinberg, C.L.; Roberts, N.J.

    1987-01-01

    This paper discusses an evaluation methodology which is used for inventory differences at the Los Alamos National Laboratory. It is recognized that there are various methods which can be, and are being, used to evaluate process inventory differences at DOE facilities. The purpose of this paper is to share our thoughts on the subject and our techniques with those who are responsible for the evaluation of inventory differences at their facility. One of the most dangerous aspects of any evaluation technique, especially one as complex as most inventory difference evaluations tend to be, is to fail to look at the tools being used as indicators. There is a tendency to look at the results of an evaluation by one technique as an absolute. At the Los Alamos National Laboratory, several tools are used and the final evaluation is based on a combination of the observed results of a many-faceted evaluation. The tools used and some examples are presented

  18. Development of fatigue life evaluation technique using miniature specimen

    International Nuclear Information System (INIS)

    Nogami, Shuhei; Nishimura, Arata; Fujiwara, Masaharu; Hisaka, Tomoaki

    2012-01-01

    To develop the fatigue life evaluation technique using miniature specimen, the investigation of the effect of specimen size and specimen shape on the fatigue life and the development of the fatigue testing machine, especially the extensometer, were carried out. The effect of specimen size on the fatigue life was almost negligible for the round-bar specimens. The shorter fatigue life at relatively low strain range conditions for the hourglass specimen that the standard specimen were observed. Therefore the miniature round-bar specimen was considered to be adequate for the fatigue life evaluation using small specimen. Several types of the extensometer system using a strain gauge and a laser has been developed for realizing the fatigue test of the miniature round-bar specimen at high temperature in vacuum. (author)

  19. Random accumulated damage evaluation under multiaxial fatigue loading conditions

    Directory of Open Access Journals (Sweden)

    V. Anes

    2015-07-01

    Full Text Available Multiaxial fatigue is a very important physical phenomenon to take into account in several mechanical components; its study is of utmost importance to avoid unexpected failure of equipment, vehicles or structures. Among several fatigue characterization tools, a correct definition of a damage parameter and a load cycle counting method under multiaxial loading conditions show to be crucial to estimate multiaxial fatigue life. In this paper, the SSF equivalent stress and the virtual cycle counting method are presented and discussed, regarding their physical foundations and their capability to characterize multiaxial fatigue damage under complex loading blocks. Moreover, it is presented their applicability to evaluate random fatigue damage.

  20. 14 CFR 29.571 - Fatigue evaluation of structure.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fatigue evaluation of structure. 29.571... § 29.571 Fatigue evaluation of structure. (a) General. An evaluation of the strength of principal... (including tolerance to flaws). The structure must be shown by analysis supported by test evidence and, if...

  1. An Integrated Health Monitoring Method for Structural Fatigue Life Evaluation Using Limited Sensor Data

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2016-11-01

    Full Text Available A general framework for structural fatigue life evaluation under fatigue cyclic loading using limited sensor data is proposed in this paper. First, limited sensor data are measured from various sensors which are preset on the complex structure. Then the strain data at remote spots are used to obtain the strain responses at critical spots by the strain/stress reconstruction method based on empirical mode decomposition (REMD method. All the computations in this paper are directly performed in the time domain. After the local stress responses at critical spots are determined, fatigue life evaluation can be performed for structural health management and risk assessment. Fatigue life evaluation using the reconstructed stresses from remote strain gauge measurement data is also demonstrated with detailed error analysis. Following this, the proposed methodology is demonstrated using a three-dimensional frame structure and a simplified airfoil structure. Finally, several conclusions and future work are drawn based on the proposed study.

  2. Thermal fatigue evaluation of piping system Tee-connections

    International Nuclear Information System (INIS)

    Metzner, K.J.; Braillard, O.; Faidy, C.; Marcelles, I.; Solin, J.; Stumpfrock, L.

    2004-01-01

    Thermal fatigue is one significant long-term degradation mechanism nuclear power plants (NPP), in particular, as operating plants become older and life time extension activities have been initiated. In general, the common thermal fatigue issues are understood and controlled by plant instrumentation systems. However, incidents in some plants indicate that certain piping system Tees are susceptible to turbulent temperature mixing effects that cannot be adequately monitored by common thermocouple instrumentation. The THERFAT project has been initiated to advance the accuracy and reliability of thermal fatigue load determination in engineering tools and research oriented approaches to outline a science based practical methodology for managing thermal fatigue risks in Tee-connections susceptible to high cyclic thermal fatigue. (orig.)

  3. Fatigue

    Science.gov (United States)

    ... to help you find out what's causing your fatigue and recommend ways to relieve it. Fatigue itself is not a disease. Medical problems, treatments, and personal habits can add to fatigue. These include Taking certain medicines, such as antidepressants, ...

  4. Fatigue Life Methodology for Tapered Hybrid Composite Flexbeams

    Science.gov (United States)

    urri, Gretchen B.; Schaff, Jeffery R.

    2006-01-01

    Nonlinear-tapered flexbeam specimens from a full-size composite helicopter rotor hub flexbeam were tested under combined constant axial tension and cyclic bending loads. Two different graphite/glass hybrid configurations tested under cyclic loading failed by delamination in the tapered region. A 2-D finite element model was developed which closely approximated the flexbeam geometry, boundary conditions, and loading. The analysis results from two geometrically nonlinear finite element codes, ANSYS and ABAQUS, are presented and compared. Strain energy release rates (G) associated with simulated delamination growth in the flexbeams are presented from both codes. These results compare well with each other and suggest that the initial delamination growth from the tip of the ply-drop toward the thick region of the flexbeam is strongly mode II. The peak calculated G values were used with material characterization data to calculate fatigue life curves for comparison with test data. A curve relating maximum surface strain to number of loading cycles at delamination onset compared well with the test results.

  5. Mobile Technology Use by People Experiencing Multiple Sclerosis Fatigue: Survey Methodology.

    Science.gov (United States)

    Van Kessel, Kirsten; Babbage, Duncan R; Reay, Nicholas; Miner-Williams, Warren M; Kersten, Paula

    2017-02-28

    Fatigue is one of the most commonly reported symptoms of multiple sclerosis (MS). It has a profound impact on all spheres of life, for people with MS and their relatives. It is one of the key precipitants of early retirement. Individual, group, and Internet cognitive behavioral therapy-based approaches to supporting people with MS to manage their fatigue have been shown to be effective. The aim of this project was to (1) survey the types of mobile devices and level of Internet access people with MS use or would consider using for a health intervention and (2) characterize the levels of fatigue severity and their impact experienced by the people in our sample to provide an estimate of fatigue severity of people with MS in New Zealand. The ultimate goal of this work was to support the future development of a mobile intervention for the management of fatigue for people with MS. Survey methodology using an online questionnaire was used to assess people with MS. A total of 51 people with MS participated. The average age was 48.5 years, and the large majority of the sample (77%) was female. Participants reported significant levels of fatigue as measured with the summary score of the Neurological Fatigue Index (mean 31.4 [SD 5.3]). Most (84%) respondents scored on average more than 3 on the fatigue severity questions, reflecting significant fatigue. Mobile phone usage was high with 86% of respondents reporting having a mobile phone; apps were used by 75% of respondents. Most participants (92%) accessed the Internet from home. New Zealand respondents with MS experienced high levels of both fatigue severity and fatigue impact. The majority of participants have a mobile device and access to the Internet. These findings, along with limited access to face-to-face cognitive behavioral therapy-based interventions, create an opportunity to develop a mobile technology platform for delivering a cognitive behavioral therapy-based intervention to decrease the severity and impact of

  6. A methodology for on-line fatigue life monitoring of Indian nuclear power plant components

    International Nuclear Information System (INIS)

    Mukhopadhyay, N.K.; Dutta, B.K.; Kushawaha, H.S.

    1992-01-01

    Fatigue is one of the most important aging effects of nuclear power plant components. Information about accumulation of fatigue helps in assessing structural degradation of the components. This assists in-service inspection and maintenance and may also support future life extension program of a plant. In the present report a methodology is being proposed for monitoring on line fatigue life of nuclear power plant components using available plant instrumentations. Major factors affecting fatigue life of a nuclear power plant components are the fluctuations of temperature, pressure and flow rate. Green's function technique is used in on line fatigue monitoring as computation time is much less than finite element method. A code has been developed which computes temperature and stress Green's functions in 2-D and axisymmetric structure by finite element method due to unit change in various fluid parameters. A post processor has also been developed which computes the temperature and stress responses using corresponding Green's functions and actual fluctuation in fluid parameters. In this post processor, the multiple site problem is solved by superimposing single site Green's function technique. It is also shown that Green's function technique is best suited for on line fatigue life monitoring of nuclear power plant components. (author). 6 refs., 43 figs

  7. A critical evaluation on the fatigue problem

    International Nuclear Information System (INIS)

    Rosa, E. da; Costa Machado Leal, L. da

    1978-01-01

    A review of the different aspects of approaches to the fatigue problems since the Woehler curves till the crack propagation is presented. The interrelationship among each one of the aspects is then carried out as well as the relation of the aspects to the different fatigue phases, since the crack nucleation till the final rupture in an attempt to unify the design procedure. (Author)

  8. Methodology for flammable gas evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, J.D., Westinghouse Hanford

    1996-06-12

    There are 177 radioactive waste storage tanks at the Hanford Site. The waste generates flammable gases. The waste releases gas continuously, but in some tanks the waste has shown a tendency to trap these flammable gases. When enough gas is trapped in a tank`s waste matrix, it may be released in a way that renders part or all of the tank atmosphere flammable for a period of time. Tanks must be evaluated against previously defined criteria to determine whether they can present a flammable gas hazard. This document presents the methodology for evaluating tanks in two areas of concern in the tank headspace:steady-state flammable-gas concentration resulting from continuous release, and concentration resulting from an episodic gas release.

  9. A combined wear-fatigue design methodology for fretting in the pressure armour layer of flexible marine risers

    OpenAIRE

    O'Halloran, S.M.; Shipway, P.H.; Connaire, A.D.; Leen, Sean B.; Harte, A.M.

    2017-01-01

    This paper presents a combined experimental and computational methodology for fretting wear-fatigue prediction of pressure armour wire in flexible marine risers. Fretting wear, friction and fatigue parameters of pressure armour material have been characterised experimentally. A combined fretting wear-fatigue finite element model has been developed using an adaptive meshing technique and the effect of bending-induced tangential slip has been characterised. It has been shown that a surface dama...

  10. Nondestructive evaluation of creep-fatigue damage: an interim report

    International Nuclear Information System (INIS)

    Nickell, R.E.

    1977-02-01

    In view of the uncertainties involved in designing against creep-fatigue failure and the consequences of such failures in Class 1 nuclear components that operate at elevated temperature, the possibility of intermittent or even continuous non-destructive examination of these components has been considered. In this interim report some preliminary results on magnetic force and ultrasonic evaluation of creep-fatigue damage in an LMFBR steam generator material are presented. These results indicate that the non-destructive evaluation of pure creep damage will be extremely difficult. A set of biaxial creep-fatigue tests that are designed to discriminate between various failure theories is also described

  11. Comparing Structural Identification Methodologies for Fatigue Life Prediction of a Highway Bridge

    Directory of Open Access Journals (Sweden)

    Sai G. S. Pai

    2018-01-01

    Full Text Available Accurate measurement-data interpretation leads to increased understanding of structural behavior and enhanced asset-management decision making. In this paper, four data-interpretation methodologies, residual minimization, traditional Bayesian model updating, modified Bayesian model updating (with an L∞-norm-based Gaussian likelihood function, and error-domain model falsification (EDMF, a method that rejects models that have unlikely differences between predictions and measurements, are compared. In the modified Bayesian model updating methodology, a correction is used in the likelihood function to account for the effect of a finite number of measurements on posterior probability–density functions. The application of these data-interpretation methodologies for condition assessment and fatigue life prediction is illustrated on a highway steel–concrete composite bridge having four spans with a total length of 219 m. A detailed 3D finite-element plate and beam model of the bridge and weigh-in-motion data are used to obtain the time–stress response at a fatigue critical location along the bridge span. The time–stress response, presented as a histogram, is compared to measured strain responses either to update prior knowledge of model parameters using residual minimization and Bayesian methodologies or to obtain candidate model instances using the EDMF methodology. It is concluded that the EDMF and modified Bayesian model updating methodologies provide robust prediction of fatigue life compared with residual minimization and traditional Bayesian model updating in the presence of correlated non-Gaussian uncertainty. EDMF has additional advantages due to ease of understanding and applicability for practicing engineers, thus enabling incremental asset-management decision making over long service lives. Finally, parallel implementations of EDMF using grid sampling have lower computations times than implementations using adaptive sampling.

  12. Fatigue evaluation of socket welded piping in nuclear power plant

    International Nuclear Information System (INIS)

    Vecchio, R.S.

    1996-01-01

    Fatigue failures in piping systems occur, almost without exception, at the welded connections. In nuclear power plant systems, such failures occur predominantly at the socket welds of small diameter piping ad fillet attachment welds under high-cycle vibratory conditions. Nearly all socket weld fatigue failures are identified by leaks which, though not high in volume, generally are costly due to attendant radiological contamination. Such fatigue cracking was recently identified in the 3/4 in. diameter recirculation and relief piping socket welds from the reactor coolant system (RCS) charging pumps at a nuclear power plant. Consequently, a fatigue evaluation was performed to determine the cause of cracking and provide an acceptable repair. Socket weld fatigue life was evaluated using S-N type fatigue life curves for welded structures developed by AASHTO and the assessment of an effective cyclic stress range adjacent to each socket weld. Based on the calculated effective tress ranges and assignment of the socket weld details to the appropriate AASHTO S-N curves, the socket weld fatigue lives were calculated and found to be in excellent agreement with the accumulated cyclic life to-date

  13. Systematic content evaluation and review of measurement properties of questionnaires for measuring self-reported fatigue among older people.

    Science.gov (United States)

    Egerton, Thorlene; Riphagen, Ingrid I; Nygård, Arnhild J; Thingstad, Pernille; Helbostad, Jorunn L

    2015-09-01

    The assessment of fatigue in older people requires simple and user-friendly questionnaires that capture the phenomenon, yet are free from items indistinguishable from other disorders and experiences. This study aimed to evaluate the content, and systematically review and rate the measurement properties of self-report questionnaires for measuring fatigue, in order to identify the most suitable questionnaires for older people. This study firstly involved identification of questionnaires that purport to measure self-reported fatigue, and evaluation of the content using a rating scale developed for the purpose from contemporary understanding of the construct. Secondly, for the questionnaires that had acceptable content, we identified studies reporting measurement properties and rated the methodological quality of those studies according to the COSMIN system. Finally, we extracted and synthesised the results of the studies to give an overall rating for each questionnaire for each measurement property. The protocol was registered with PROSPERO (CRD42013005589). Of the 77 identified questionnaires, twelve were selected for review after content evaluation. Methodological quality varied, and there was a lack of information on measurement error and responsiveness. The PROMIS-Fatigue item bank and short forms perform the best. The FACIT-Fatigue scale, Parkinsons Fatigue Scale, Perform Questionnaire, and Uni-dimensional Fatigue Impact Scale also perform well and can be recommended. Minor modifications to improve performance are suggested. Further evaluation of unresolved measurement properties, particularly with samples including older people, is needed for all the recommended questionnaires.

  14. Evaluation of upper limb muscle fatigue based on surface electromyography.

    Science.gov (United States)

    Zhou, Qianxiang; Chen, Yuhong; Ma, Chao; Zheng, Xiaohui

    2011-10-01

    Fatigue is believed to be a major contributory factor to occupational injuries in machine operators. The development of accurate and usable techniques to measure operator fatigue is therefore important. In this study, we used a novel method based on surface electromyography (sEMG) of the biceps brachii and the Borg scale to evaluate local muscle fatigue in the upper limb after isometric muscle action. Thirteen young males performed isometric actions with the upper limb at different force levels. sEMG activities of the biceps brachii were recorded during the actions. Borg scales were used to evaluate the subjective sensation of local fatigue of the biceps brachii after the actions. sEMG activities were analyzed using the one-third band octave method, and an equation to determine the degree of fatigue was derived based on the relationship between the variable and the Borg scale. The results showed that the relationship could be expressed by a conic curve, and could be used to evaluate muscle fatigue during machine operation.

  15. Keep fatigue usage low for LTO. Benefits of load monitoring and related fatigue evaluations for long term operation

    International Nuclear Information System (INIS)

    Rothenhoefer, H.; Koenig, G.

    2012-01-01

    Design fatigue calculations normally cover a service life of 40 years. Based on design transients with a specified number of cycles the evaluations have to prove that the fatigue usage after 40 years will stay below 1. In 40+ years of operation real loads can differ much from design loads so that premature ageing can occur. For long term operation, monitoring of real loads and detailed fatigue analysis for selected locations can be used to optimize operational modes in order to reduce the loads causing fatigue. As a result fatigue usage can be kept below 1 even for 60+ years. (author)

  16. Development of thermal fatigue evaluation methods of piping systems

    International Nuclear Information System (INIS)

    Kasahara, Naoto; Itoh, Takamoto; Okazaki, Masakazu; Okuda, Yukihiko; Kamaya, Masayuki; Nakamura, Akira; Nakamura, Hitoshi; Machida, Hideo; Matsumoto, Masaaki

    2013-01-01

    Nuclear piping has various kinds of thermal fatigue failure modes. Main causes of thermal loads are structural responses to fluid temperature changes during plant operation. These phenomena have complex mechanisms and so many patterns, that their problems still occur even though well-known issues. To prevent thermal fatigue due to above thermal loads, the JSME guideline is adopted. Both thermal load and fatigue failure mechanism have been investigated and summarized into the knowledgebase. Based on above knowledge, improved methods for the JSME guideline and Numerical simulation methods for thermal fatigue evaluation were studied. Furthermore, probabilistic failure analysis approach with main influence parameters were investigated to be applied for the plant system safety. (author)

  17. Development of fatigue life evaluation method using small specimen

    International Nuclear Information System (INIS)

    Nogami, Shuhei; Nishimura, Arata; Wakai, Eichi; Tanigawa, Hiroyasu; Itoh, Takamoto; Hasegawa, Akira

    2013-01-01

    For developing the fatigue life evaluation method using small specimen, the effect of specimen size and shape on the fatigue life of the reduced activation ferritic/martensitic steels (F82H-IEA, F82H-BA07 and JLF-1) was investigated by the fatigue test at room temperature in air using round-bar and hourglass specimens with various specimen sizes (test section diameter: 0.85–10 mm). The round-bar specimen showed no specimen size and no specimen shape effects on the fatigue life, whereas the hourglass specimen showed no specimen size effect and obvious specimen shape effect on it. The shorter fatigue life of the hourglass specimen observed under low strain ranges could be attributed to the shorter micro-crack initiation life induced by the stress concentration dependent on the specimen shape. On the basis of this study, the small round-bar specimen was an acceptable candidate for evaluating the fatigue life using small specimen

  18. Fatigue evaluation of piping connections under thermal transients

    International Nuclear Information System (INIS)

    Aquino, C.T.E. de; Maneschy, J.E.

    1993-01-01

    In designing nuclear power plant piping, thermal transients, caused by non-steady operation conditions, should be considered. These events may reduce considerably the lifetime of the pipes, creating the necessity of using structural elements designed in such a way to minimize the acting thermal stresses. Typical examples of the usage of these elements are the connections between pipes of small and large diameters, in which it is usually used a weldolet. Nevertheless, in some situations, the thermal stresses caused by the transients are greater than the allowable limits, being, in this case, an alternative for best results, the introduction of a special fitting replacing the weldolet. Such a fitting is designed in a way to permit a better distribution of the stresses, reducing its maximum value to acceptable levels. This paper intends to present a fatigue evaluation of a connection, using the above mentioned fitting, when subjected to a load expressed in terms of a step thermal gradient, varying from 263 deg to 40 deg C. Two different methodologies are used in this analysis: (a) Determination of the temperature distribution from the heat transfer equations for piping, being the stresses calculated according to ASME III NB-3600. (b) Thermal and stress analyses using axisymmetric elements, according to the rules presented at ASME III NB-3200. In the first case, named simplified analysis, the computer code used is the PIPESTRESS, while in the second case, the ANSYS program was adopted

  19. Detecting fatigue thresholds from electromyographic signals: A systematic review on approaches and methodologies.

    Science.gov (United States)

    Ertl, Peter; Kruse, Annika; Tilp, Markus

    2016-10-01

    The aim of the current paper was to systematically review the relevant existing electromyographic threshold concepts within the literature. The electronic databases MEDLINE and SCOPUS were screened for papers published between January 1980 and April 2015 including the keywords: neuromuscular fatigue threshold, anaerobic threshold, electromyographic threshold, muscular fatigue, aerobic-anaerobictransition, ventilatory threshold, exercise testing, and cycle-ergometer. 32 articles were assessed with regard to their electromyographic methodologies, description of results, statistical analysis and test protocols. Only one article was of very good quality. 21 were of good quality and two articles were of very low quality. The review process revealed that: (i) there is consistent evidence of one or two non-linear increases of EMG that might reflect the additional recruitment of motor units (MU) or different fiber types during fatiguing cycle ergometer exercise, (ii) most studies reported no statistically significant difference between electromyographic and metabolic thresholds, (iii) one minute protocols with increments between 10 and 25W appear most appropriate to detect muscular threshold, (iv) threshold detection from the vastus medialis, vastus lateralis, and rectus femoris is recommended, and (v) there is a great variety in study protocols, measurement techniques, and data processing. Therefore, we recommend further research and standardization in the detection of EMGTs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Methodology of formal software evaluation

    International Nuclear Information System (INIS)

    Tuszynski, J.

    1998-01-01

    Sydkraft AB, the major Swedish utility, owner of ca 6000 MW el installed in nuclear (NPP Barsebaeck and NPP Oskarshamn), fossil fuel and hydro Power Plants is facing modernization of the control systems of the plants. Standards applicable require structured, formal methods for implementation of the control functions in the modem, real time software systems. This presentation introduces implementation methodology as discussed presently at the Sydkraft organisation. The approach suggested is based upon the process of co-operation of three parties taking part in the implementation; owner of the plant, vendor and Quality Assurance (QA) organisation. QA will be based on tools for formal software validation and on systematic gathering by the owner of validated and proved-by-operation control modules for the concern-wide utilisation. (author)

  1. Elastic creep-fatigue evaluation for ASME code

    International Nuclear Information System (INIS)

    Severud, L.K.; Winkel, B.V.

    1987-01-01

    Experience with applying the ASME Code Case N-47 rules for evaluation of creep-fatigue with elastic analysis results has been problematic. The new elastic evaluation methods are intended to bound the stress level and strain range values needed for use in employing the code inelastic analysis creep-fatigue damage counting procedures. To account for elastic followup effects, ad hoc rules for stress classification, shakedown, and ratcheting are employed. Because elastic followup, inelastic strain concentration, and stress-time effects are accounted for, the design fatigue curves in Case N-47 for inelastic analysis are used instead of the more conservative elastic analysis curves. Creep damage assessments are made using an envelope stress-time history that treats multiple load events and repeated cycles during elevated temperature service life. (orig./GL)

  2. Nuclear power plant simulation facility evaluation methodology

    International Nuclear Information System (INIS)

    Haas, P.M.; Carter, R.J.; Laughery, K.R. Jr.

    1985-01-01

    A methodology for evaluation of nuclear power plant simulation facilities with regard to their acceptability for use in the US Nuclear Regulatory Commission (NRC) operator licensing exam is described. The evaluation is based primarily on simulator fidelity, but incorporates some aspects of direct operator/trainee performance measurement. The panel presentation and paper discuss data requirements, data collection, data analysis and criteria for conclusions regarding the fidelity evaluation, and summarize the proposed use of direct performance measurment. While field testing and refinement of the methodology are recommended, this initial effort provides a firm basis for NRC to fully develop the necessary methodology

  3. Fatigue cycles evaluation of 500 MWe PHWR coolant channel sealdisc

    International Nuclear Information System (INIS)

    Chawla, D.S.; Vaze, K.K.; Kushwaha, H.S.; Gupta, K.S.; Bhambra, H.S.

    1998-07-01

    At each end of coolant channel there is one sealing plug assembly. The sealdisc is a part of sealing plug assembly. The sealdisc is used to avoid leakage of heavy water. The importance of sealdisc can be understood by the fact that there are 784 sealdiscs in one 500 MWe PHWR unit. During the life time of reactor the sealdisc will be subjected to cyclic loads due to reactor startup, shutdown, power setback and also due to refuelling operations. Excessive reversal of stresses may lead to fatigue failure. The sealdisc failure may cause loss of coolant accidents. Since sealdisc is safety class 1 component, it has to be qualified according to ASME Section III Division 1 NB. For cyclic loads, the fatigue analysis is essential to assess the allowable number of cycles and also to check the total usage factor due to different cyclic loads. To evaluate the allowable fatigue cycles, the analysis is carried out using finite element method. The present report deals with the fatigue cycles evaluation of 500 MWe PHWR sealdisc. The finite element model having eight noded axisymmetric elements is used for the analysis. The various loads considered in the analysis are mechanical loads arising due to refuelling operations and number of temperature-pressure transients. During refuelling, the sealdisc is removed and reinstalled back by use of fuelling machine ram which applies load at centre as well as at rocker point of sealdisc. The stress analysis is carried out for each stage of loading during refuelling and fatigue cycles are evaluated. For temperature transient, decoupled thermal analysis is carried out. At various instants of time, the stresses are computed using temperatures calculated in thermal analysis. The pressure variation is also considered along with temperature variation. The fatigue cycles are evaluated for each transient using maximum alternating stress intensities. The usage factors are calculated for various temperature/pressure transients and refuelling loads

  4. Fatigue

    Science.gov (United States)

    ... sleep. Fatigue is a lack of energy and motivation. Drowsiness and apathy (a feeling of not caring ... Call your provider right away if you have any of the following: Confusion or dizziness Blurred vision Little or no urine, or recent ...

  5. PWR reload safety evaluation methodology

    International Nuclear Information System (INIS)

    Doshi, P.K.; Chapin, D.L.; Love, D.S.

    1993-01-01

    The current practice for WWER safety analysis is to prepare the plant Safety Analysis Report (SAR) for initial plant operation. However, the existing safety analysis is typically not evaluated for reload cycles to confirm that all safety limits are met. In addition, there is no systematic reanalysis or reevaluation of the safety analyses after there have been changes made to the plant. The Westinghouse process is discussed which is in contrast to this and in which the SAR conclusions are re-validated through evaluation and/or analysis of each reload cycle. (Z.S.)

  6. Incorporating the effects of environment in fatigue evaluations

    International Nuclear Information System (INIS)

    Huettner, C.; Dittmar, S.

    2003-01-01

    There are national and international activities for assessing the influence of the environment on fatigue of austenitic and ferritic components. On the basis of the results obtained, specifications for nuclear and conventional power plants are re-evaluated with a view to their accuracy in taking account of the influence of the environment in German nuclear power stations. In particular, KTA 3201.2 and KTA 3211.2 are gone into. The draft KTA 3211.2 contains qualitative specifications for taking account of the environment. Especially in the USA, methods were developed which take account of the environment in fatigue analyses as a function of several different influencing parameters. These methods are presented, and it is discussed inhowfar they should be taken into consideration in fatigue analyses according to KTA specifications. (orig.) [de

  7. Covariance Evaluation Methodology for Neutron Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.

    2008-09-01

    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  8. Collect Available Creep-Fatigue Data and Study Existing Creep-Fatigue Evaluation Procedures for Grade 91 and Hastelloy XR

    International Nuclear Information System (INIS)

    Asayama, Tai; Tachibana, Yukio

    2007-01-01

    This report describes the results of investigation on Task 5 of DOE/ASME Materials Project based on a contract between ASME Standards Technology, LLC (ASME ST-LLC) and Japan Atomic Energy Agency (JAEA). Task 5 is to collect available creep-fatigue data and study existing creep-fatigue evaluation procedures for Grade 91 steel and Hastelloy XR. Part I of this report is devoted to Grade 91 steel. Existing creep-fatigue data were collected (Appendix A) and analyzed from the viewpoints of establishing a creep-fatigue procedure for VHTR design. A fair amount of creep-fatigue data has been obtained and creep-fatigue phenomena have been clarified to develop design standards mainly for fast breeder reactors. Following this, existing creep-fatigue procedures were studied and it was clarified that the creep-fatigue evaluation procedure of the ASME-NH has a lot of conservatisms and they were analyzed in detail from the viewpoints of the evaluation of creep damage of material. Based on the above studies, suggestions to improve the ASME-NH procedure along with necessary research and development items were presented. Part II of this report is devoted to Hastelloy XR. Existing creep-fatigue data used for development of the high temperature structural design guideline for High Temperature Gas-cooled Reactor (HTGR) were collected. Creep-fatigue evaluation procedure in the design guideline and its application to design of the intermediate heat exchanger (IHX) for High Temperature Engineering Test Reactor (HTTR) was described. Finally, some necessary research and development items in relation to creep-fatigue evaluation for Gen IV and VHTR reactors were presented.

  9. Lifetime evaluation for thermal fatigue: application at the first wall of a tokamak fusion reactor

    International Nuclear Information System (INIS)

    Merola, M.; Biggio, M.

    1989-01-01

    Thermal fatigue seems to be the most lifetime limiting phenomenon for the first wall of the next generation Tokamak fusion reactors. This work deals with the problem of the thermal fatigue in relation to the lifetime prediction of the fusion reactor first wall. The aim is to compare different lifetime methodologies among them and with experimental results. To fulfil this purpose, it has been necessary to develop a new numerical methodology, called reduced-3D, especially suitable for thermal fatigue problems

  10. Evaluating fatigue in lupus-prone mice: preliminary assessments.

    Science.gov (United States)

    Meeks, Allison; Larson, Susan J

    2012-01-01

    Fatigue is a debilitating condition suffered by many as the result of chronic disease, yet relatively little is known about its biological basis or how to effectively manage its effects. This study sought to evaluate chronic fatigue by using lupus-prone mice and testing them at three different time periods. Lupus-prone mice were chosen because fatigue affects over half of patients with Systemic Lupus Erythematosus. Eleven MLR⁺/(+) (genetic controls) and twelve MLR/MpJ-Fas/J (MRL/lpr; lupus-prone) mice were tested three times: once at 12, 16 and 20 weeks of age. All mice were subjected to a variety of behavioral tests including: forced swim, post-swim grooming, running wheel, and sucrose consumption; five of the MLR⁺/(+) and five of the MLR/lpr mice were also tested on a fixed ratio-25 operant conditioning task. MRL/lpr mice showed more peripheral symptoms of lupus than controls, particularly lymphadenopathy and proteinuria. Lupus mice spent more time floating during the forced swim test and traveled less distance in the running wheel at each testing period. There were no differences between groups in post-swim grooming or in number of reinforcers earned in the operant conditioning task indicating the behavioral changes were not likely due simply to muscle weakness or motivation. Correlations between performance in the running wheel, forced swim test and sucrose consumption were conducted and distance traveled in the running wheel was consistently negatively correlated with time spent floating. Based on these data, we conclude that the lupus-prone mice were experiencing chronic fatigue and that running wheel activity and floating during a forced swim test can be used to evaluate fatigue, although these data cannot rule out the possibility that both fatigue and a depressive-like state were mediating these effects. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Comparison of evaluation results of piping thermal fatigue evaluation method based on equivalent stress amplitude

    International Nuclear Information System (INIS)

    Suzuki, Takafumi; Kasahara, Naoto

    2012-01-01

    In recent years, reports have increased about failure cases caused by high cycle thermal fatigue both at light water reactors and fast breeder reactors. One of the reasons of the cases is a turbulent mixing at a Tee-junction, where hot and cold temperature fluids are mixed, in a coolant system. In order to prevent thermal fatigue failures at Tee-junctions. The Japan Society of Mechanical Engineers published the guideline which is an evaluation method of high cycle thermal fatigue damage at nuclear pipes. In order to justify safety margin and make the procedure of the guideline concise, this paper proposes a new evaluation method of thermal fatigue damage with use of the 'equivalent stress amplitude.' Because this new method makes procedure of evaluation clear and concise, it will contribute to improving the guideline for thermal fatigue evaluation. (author)

  12. Health economic evaluation: important principles and methodology.

    Science.gov (United States)

    Rudmik, Luke; Drummond, Michael

    2013-06-01

    To discuss health economic evaluation and improve the understanding of common methodology. This article discusses the methodology for the following types of economic evaluations: cost-minimization, cost-effectiveness, cost-utility, cost-benefit, and economic modeling. Topics include health-state utility measures, the quality-adjusted life year (QALY), uncertainty analysis, discounting, decision tree analysis, and Markov modeling. Economic evaluation is the comparative analysis of alternative courses of action in terms of both their costs and consequences. With increasing health care expenditure and limited resources, it is important for physicians to consider the economic impact of their interventions. Understanding common methodology involved in health economic evaluation will improve critical appraisal of the literature and optimize future economic evaluations. Copyright © 2012 The American Laryngological, Rhinological and Otological Society, Inc.

  13. 77 FR 4890 - Damage Tolerance and Fatigue Evaluation for Composite Rotorcraft Structures, and Damage Tolerance...

    Science.gov (United States)

    2012-02-01

    ...-AJ52, 2120-AJ51 Damage Tolerance and Fatigue Evaluation for Composite Rotorcraft Structures, and Damage Tolerance and Fatigue Evaluation for Metallic Structures; Correction AGENCY: Federal Aviation Administration... Tolerance and Fatigue Evaluation for Composite Rotorcraft Structures'' (76 FR 74655), published December 1...

  14. Framework of Comprehensive Proliferation Resistance Evaluation Methodology

    International Nuclear Information System (INIS)

    Kim, Min Su; Jo, Seong Youn; Kim, Min Soo; Kim, Jae San; Lee, Hyun Kyung

    2007-01-01

    Civilian nuclear programs can be used as a pretext to acquire technologies, materials, equipment for military weapon programs. Consequently, international society has a strong incentive to develop a nuclear system more proliferation resistant to assure that the civilian nuclear energy system is an unattractive and least desirable route for diversion of weapon usable material. The First step developing a more proliferation resistant nuclear energy system is to develop a systematic and standardized evaluation methodology to ensure that any future nuclear energy system satisfies the proliferation resistance goals. Many attempts to develop systematic evaluation methodology have been proposed and many systems for assessing proliferation resistance have been previously studied. However, a comprehensive proliferation resistance evaluation can not be achieved by simply applying one method since complicated proliferation resistance characteristics, including inherent features and extrinsic features, should be completely evaluated. Therefore, it is necessary to develop one incorporated evaluation methodology to make up for weak points of each evaluation method. The objective of this study is to provide a framework of comprehensive proliferation resistance evaluation methodology by incorporating two generally used evaluation methods, attribute and scenario analysis

  15. Methodology for quantitative evaluation of diagnostic performance

    International Nuclear Information System (INIS)

    Metz, C.

    1981-01-01

    Of various approaches that might be taken to the diagnostic performance evaluation problem, Receiver Operating Characteristic (ROC) analysis holds great promise. Further development of the methodology for a unified, objective, and meaningful approach to evaluating the usefulness of medical imaging procedures is done by consideration of statistical significance testing, optimal sequencing of correlated studies, and analysis of observer performance

  16. Methodology for evaluation of industrial CHP production

    International Nuclear Information System (INIS)

    Pavlovic, Nenad V.; Studovic, Milovan

    2000-01-01

    At the end of the century industry switched from exclusive power consumer into power consumer-producer which is one of the players on the deregulated power market. Consequently, goals of industrial plant optimization have to be changed, making new challenges that industrial management has to be faced with. In the paper is reviewed own methodology for evaluation of industrial power production on deregulated power market. The methodology recognizes economic efficiency of industrial CHP facilities as a main criterion for evaluation. Energy and ecological efficiency are used as additional criteria, in which implicit could be found social goals. Also, methodology recognizes key and limit factors for CHP production in industry. It could be successful applied, by use of available commercial software for energy simulation in CHP plants and economic evaluation. (Authors)

  17. Review and evaluation of paleohydrologic methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Foley, M.G.; Zimmerman, D.A.; Doesburg, J.M.; Thorne, P.D.

    1982-12-01

    A literature review was conducted to identify methodologies that could be used to interpret paleohydrologic environments. Paleohydrology is the study of past hydrologic systems or of the past behavior of an existing hydrologic system. The purpose of the review was to evaluate how well these methodologies could be applied to the siting of low-level radioactive waste facilities. The computer literature search queried five bibliographical data bases containing over five million citations of technical journals, books, conference papers, and reports. Two data-base searches (United States Geological Survey - USGS) and a manual search were also conducted. The methodologies were examined for data requirements and sensitivity limits. Paleohydrologic interpretations are uncertain because of the effects of time on hydrologic and geologic systems and because of the complexity of fluvial systems. Paleoflow determinations appear in many cases to be order-of-magnitude estimates. However, the methodologies identified in this report mitigate this uncertainty when used collectively as well as independently. That is, the data from individual methodologies can be compared or combined to corroborate hydrologic predictions. In this manner, paleohydrologic methodologies are viable tools to assist in evaluating the likely future hydrology of low-level radioactive waste sites.

  18. Review and evaluation of paleohydrologic methodologies

    International Nuclear Information System (INIS)

    Foley, M.G.; Zimmerman, D.A.; Doesburg, J.M.; Thorne, P.D.

    1982-12-01

    A literature review was conducted to identify methodologies that could be used to interpret paleohydrologic environments. Paleohydrology is the study of past hydrologic systems or of the past behavior of an existing hydrologic system. The purpose of the review was to evaluate how well these methodologies could be applied to the siting of low-level radioactive waste facilities. The computer literature search queried five bibliographical data bases containing over five million citations of technical journals, books, conference papers, and reports. Two data-base searches (United States Geological Survey - USGS) and a manual search were also conducted. The methodologies were examined for data requirements and sensitivity limits. Paleohydrologic interpretations are uncertain because of the effects of time on hydrologic and geologic systems and because of the complexity of fluvial systems. Paleoflow determinations appear in many cases to be order-of-magnitude estimates. However, the methodologies identified in this report mitigate this uncertainty when used collectively as well as independently. That is, the data from individual methodologies can be compared or combined to corroborate hydrologic predictions. In this manner, paleohydrologic methodologies are viable tools to assist in evaluating the likely future hydrology of low-level radioactive waste sites

  19. Methodology for evaluation of diagnostic performance

    International Nuclear Information System (INIS)

    Metz, C.E.

    1992-01-01

    Effort in this project during the past year has focused on the development, refinement, and distribution of computer software that will allow current Receiver Operating Characteristic (ROC) methodology to be used conveniently and reliably by investigators in a variety of evaluation tasks in diagnostic medicine; and on the development of new ROC methodology that will broaden the spectrum of evaluation tasks and/or experimental settings to which the fundamental approach can be applied. Progress has been limited by the amount of financial support made available to the project

  20. 75 FR 793 - Damage Tolerance and Fatigue Evaluation of Composite Rotorcraft Structures

    Science.gov (United States)

    2010-01-06

    ... metal structures are different. Composites are complex materials that have unique advantages in fatigue... stiffness, dynamic behavior, loads, and functional performance of composite structures. In the existing rule... and Fatigue Evaluation of Composite Rotorcraft Structures AGENCY: Federal Aviation Administration (FAA...

  1. Demonstration of an infiltration evaluation methodology

    International Nuclear Information System (INIS)

    Smyth, J.D.; Gee, G.W.; Kincaid, C.T.; Nichols, W.M.; Bresler, E.

    1990-07-01

    An Infiltration Evaluation Methodology (IEM) was developed for the US Nuclear Regulatory Commission (NRC) by Pacific Northwest Laboratory (PNL) to provide a consistent, well formulated approach for evaluating drainage through engineered covers at low-level radioactive waste (LLW) sites. The methodology is designed to help evaluate the ability of proposed waste site covers to minimize drainage for LLW site license applications and for sites associated with the Uranium Mill Tailings Remedial Action (UMTRA) program. The objective of this methodology is to estimate the drainage through an engineered burial site cover system. The drainage estimate can be used as an input to a broader performance assessment methodology currently under development by the NRC. The methodology is designed to simulate, at the field scale, significant factors and hydrologic conditions which determine or influence estimates of infiltration, long-term moisture content profiles, and drainage from engineered covers and barriers. The IEM developed under this study acknowledges the uncertainty inherent in soil properties and quantifies the influence of such uncertainty on the estimates of drainage in engineered cover systems at waste disposal sites. 6 refs., 1 fig

  2. Systematic Review Methodology for the Fatigue in Emergency Medical Services Project

    Science.gov (United States)

    2018-01-11

    Background: Guidance for managing fatigue in the Emergency Medical Services (EMS) setting is limited. The Fatigue in EMS Project sought to complete multiple systematic reviews guided by seven explicit research questions, assemble the best available e...

  3. Fatigue methodology for life predictions for the wheel-rail contact area in large offshore turret bearings

    Directory of Open Access Journals (Sweden)

    T. Lassen

    2016-10-01

    Full Text Available The present report presents a fatigue life prediction method for large roller bearings applied in the turret turn table for large loading buoy units. The contact points between wheel and rail in these bearings are subjected to a multi-axial fluctuating stress situation and both surface wear and fatigue cracking may occur. A methodology based on the Dang Van fatigue criterion is adopted. The criterion is based on an equivalent stress defined as a combination of the fluctuation of the shear stress from its mean value at a critical plane and the associated hydrostatic stress at the given time. The present work is supporting the theoretical model by extensive laboratory testing. Both full scale testing of wheel on rail and small scale testing for characterizing the steel material are carried out. An experimental program was carried out with the high strength stainless steel S165M. The Dang Van stress concept is applied in combination with the Random Fatigue Limit Method (RFLM for life data analyses. This approach gives the opportunity to include both finite lives and the run-outs in a rational manner without any presumption of the existence of a fatigue limit in advance of the data. This gives a non-linear S-N curve for a log-log scale in the very high cycle regime close to the fatigue limit. It is demonstrated how the scatter in fatigue limit decreases when the Dang Van stress concept is applied and that the fatigue limit is occurring beyond 107 cycles

  4. Evaluation of Work Fatigue in Loading Workers Using Muscle Fatigue Assessment Method (MFA: A Case Study in a Brick Factory

    Directory of Open Access Journals (Sweden)

    Haji Omid Kalte

    2016-09-01

    Full Text Available Introduction and purpose: Work fatigue is one of the main causes of workrelated musculoskeletal disorders and reduced productivity in industry. Therefore, it is vital to evaluate work fatigue, especially muscle fatigue, to determine the permissible workload. This study aimed to evaluate muscle fatigue of brick field workers. Methods: This cross-sectional study was conducted on transportation sector workers in Pey Dezh Brick Production Company, Golestan, Iran in 2015. In this research, the qualitative of Muscle Fatigue Assessment (MFA method was used to assess the level of fatigue. Duration of each task and frequency of efforts were determined using the level of effort to obtain a numerical result for comparison with the standard level. Results: The evaluated task was to remove paired bricks from the conveyor and transfer them to trailer truck by workers. The final results revealed that lower back tolerated the most amount of pressure (score=323, followed by the shoulders and wrist of the right hand (scores=313, which were assigned to the fatigue level. Therefore, the highest total fatigue of workload was imposed on these body parts. Conclusion: According to the results of this study, the upper limbs of workers incurred the highest burden in lifting bricks, and there was a in risk of WMSDS due to high workload. Therefore, it is recommended that working systems be improved through rotating work and reducing the number of transferred bricks to avoid risks caused by accumulation of fatigue.

  5. Fatigue evaluation of piping systems with limited vibration test data

    International Nuclear Information System (INIS)

    Huang, S.N.

    1990-11-01

    The safety-related piping in a nuclear power plant may be subjected to pump- or fluid-induced vibrations that, in general, affect only local areas of the piping systems. Pump- or fluid-induced vibrations typically are characterized by low levels of amplitudes and a high number of cycles over the lifetime of plant operation. Thus, the resulting fatigue damage to the piping systems could be an important safety concern. In general, tests and/or analyses are used to evaluate and qualify the piping systems. Test data, however, may be limited because of lack of instrumentation in critical piping locations and/or because of difficulty in obtaining data in inaccessible areas. This paper describes and summarizes a method to use limited pipe vibration test data, along with analytical harmonic response results from finite-element analyses, to assess the fatigue damage of nuclear power plant safety-related piping systems. 5 refs., 2 figs., 11 tabs

  6. Development and Application of a Clinical Microsystem Simulation Methodology for Human Factors-Based Research of Alarm Fatigue.

    Science.gov (United States)

    Kobayashi, Leo; Gosbee, John W; Merck, Derek L

    2017-07-01

    (1) To develop a clinical microsystem simulation methodology for alarm fatigue research with a human factors engineering (HFE) assessment framework and (2) to explore its application to the comparative examination of different approaches to patient monitoring and provider notification. Problems with the design, implementation, and real-world use of patient monitoring systems result in alarm fatigue. A multidisciplinary team is developing an open-source tool kit to promote bedside informatics research and mitigate alarm fatigue. Simulation, HFE, and computer science experts created a novel simulation methodology to study alarm fatigue. Featuring multiple interconnected simulated patient scenarios with scripted timeline, "distractor" patient care tasks, and triggered true and false alarms, the methodology incorporated objective metrics to assess provider and system performance. Developed materials were implemented during institutional review board-approved study sessions that assessed and compared an experimental multiparametric alerting system with a standard monitor telemetry system for subject response, use characteristics, and end-user feedback. A four-patient simulation setup featuring objective metrics for participant task-related performance and response to alarms was developed along with accompanying structured HFE assessment (questionnaire and interview) for monitor systems use testing. Two pilot and four study sessions with individual nurse subjects elicited true alarm and false alarm responses (including diversion from assigned tasks) as well as nonresponses to true alarms. In-simulation observation and subject questionnaires were used to test the experimental system's approach to suppressing false alarms and alerting providers. A novel investigative methodology applied simulation and HFE techniques to replicate and study alarm fatigue in controlled settings for systems assessment and experimental research purposes.

  7. Gamma ray auto absorption correction evaluation methodology

    International Nuclear Information System (INIS)

    Gugiu, Daniela; Roth, Csaba; Ghinescu, Alecse

    2010-01-01

    Neutron activation analysis (NAA) is a well established nuclear technique, suited to investigate the microstructural or elemental composition and can be applied to studies of a large variety of samples. The work with large samples involves, beside the development of large irradiation devices with well know neutron field characteristics, the knowledge of perturbing phenomena and adequate evaluation of correction factors like: neutron self shielding, extended source correction, gamma ray auto absorption. The objective of the works presented in this paper is to validate an appropriate methodology for gamma ray auto absorption correction evaluation for large inhomogeneous samples. For this purpose a benchmark experiment has been defined - a simple gamma ray transmission experiment, easy to be reproduced. The gamma ray attenuation in pottery samples has been measured and computed using MCNP5 code. The results show a good agreement between the computed and measured values, proving that the proposed methodology is able to evaluate the correction factors. (authors)

  8. Fatigue Design Evaluation of Railway Bogie with Full-Scale Fatigue Test

    Directory of Open Access Journals (Sweden)

    Jung-Won Seo

    2017-01-01

    Full Text Available The bogie frame of a railway is an important structural member for the support of vehicle loading. In general, more than 25 years’ durability is necessary. Much study has been carried out in experimental and theoretical domains on the prediction of the structural integrity of the bogie frame. The objective of this paper is to estimate the structural integrity of the bogie frame of an electric railcar. Strength analysis has been performed by finite element analysis. From this analysis, stress concentration areas were investigated. To evaluate the loading conditions, dynamic stress was measured by strain gauge. It has been found that the stress and strain due to the applied loads were multiaxial conditions according to the location of the strain gauge. Fatigue strength evaluations of the bogie frame were performed to investigate the effect of a multiaxial load through the employment of a critical plane approach.

  9. Risk-based Regulatory Evaluation Program methodology

    International Nuclear Information System (INIS)

    DuCharme, A.R.; Sanders, G.A.; Carlson, D.D.; Asselin, S.V.

    1987-01-01

    The objectives of this DOE-supported Regulatory Evaluation Progrwam are to analyze and evaluate the safety importance and economic significance of existing regulatory guidance in order to assist in the improvement of the regulatory process for current generation and future design reactors. A risk-based cost-benefit methodology was developed to evaluate the safety benefit and cost of specific regulations or Standard Review Plan sections. Risk-based methods can be used in lieu of or in combination with deterministic methods in developing regulatory requirements and reaching regulatory decisions

  10. Common methodological flaws in economic evaluations.

    Science.gov (United States)

    Drummond, Michael; Sculpher, Mark

    2005-07-01

    Economic evaluations are increasingly being used by those bodies such as government agencies and managed care groups that make decisions about the reimbursement of health technologies. However, several reviews of economic evaluations point to numerous deficiencies in the methodology of studies or the failure to follow published methodological guidelines. This article, written for healthcare decision-makers and other users of economic evaluations, outlines the common methodological flaws in studies, focussing on those issues that are likely to be most important when deciding on the reimbursement, or guidance for use, of health technologies. The main flaws discussed are: (i) omission of important costs or benefits; (ii) inappropriate selection of alternatives for comparison; (iii) problems in making indirect comparisons; (iv) inadequate representation of the effectiveness data; (v) inappropriate extrapolation beyond the period observed in clinical studies; (vi) excessive use of assumptions rather than data; (vii) inadequate characterization of uncertainty; (viii) problems in aggregation of results; (ix) reporting of average cost-effectiveness ratios; (x) lack of consideration of generalizability issues; and (xi) selective reporting of findings. In each case examples are given from the literature and guidance is offered on how to detect flaws in economic evaluations.

  11. Evaluation of Fatigue Behavior in Dental Implants from In Vitro Clinical Tests: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Rosa Rojo

    2018-05-01

    Full Text Available In the area of dentistry, there is a wide variety of designs of dental implant and materials, especially titanium, which aims to avoid failures and increase their clinical durability. The purpose of this review was to evaluate fatigue behavior in different connections and implant materials, as well as their loading conditions and response to failure. In vitro tests under normal and dynamic loading conditions evaluating fatigue at implant and abutment connection were included. A search was conducted in PubMed, Scopus, and Science Direct. Data extraction was performed independently by two reviewers. The quality of selected studies was assessed using the Cochrane Handbook proposed by the tool for clinical trials. Nineteen studies were included. Fourteen studies had an unclear risk and five had high risk of bias. Due to the heterogeneity of the data and the evaluation of the quality of the studies, meta-analysis could not be performed. Evidence from this study suggests that both internal and morse taper connections presented a better behavior to failure. However, it is necessary to unify criteria in the methodological design of in vitro studies, following methodological guidelines and establishing conditions that allow the homogenization of designs in ISO (International Organization for Standardization standards.

  12. Methodologies for evaluation of AECB regulatory program

    International Nuclear Information System (INIS)

    Yarranton, G.A.; Gray, B.J.; Yarranton, M.

    1986-05-01

    AECB (Atomic Energy Control Board) commissioned this report to obtain information about methods of planning and conducting evaluation of its regulatory program. The report begins with a bibliography consisting of 280 abstracts assembled from an extensive search of international literature. Each cited publication describes or uses methods applicable to the evaluation of regulatory programs. The report continues with a review of the methodologies found in the literature. It identifies the most relevant references for each step in program evaluation: the commissioning of evaluation; the identification of evaluation issues; the defining of questions; the answering of questions; the reporting of reslts, and the implementation of recommendations. Finally, the report examines the applicability, advantages and disadvantages of the different evaluation methods and makes recommendations about the selection of methods and their application to the AECB program

  13. Evaluation of long term creep-fatigue life for type 304 stainless steel

    International Nuclear Information System (INIS)

    Kawasaki, Hirotsugu; Ueno, Fumiyoshi; Aoto, Kazumi; Ichimiya, Masakazu; Wada, Yusaku

    1992-01-01

    The long term creep-fatigue life of type 304 stainless steel was evaluated by the creep-fatigue life prediction method based on a linear damage fraction rule. The displacement controlled creep-fatigue tests were carried out, and the time to failure of longer than 10000 hours was obtained. The creep damage of long term creep-fatigue was evaluated by taking into account the stress relaxation behavior with elastic follow-up during the hold period. The relationship between life reduction of creep-fatigue and fracture mode was provided by the creep cavity growth. The results of this study are summarized as follows; (1) The long term creep-fatigue data can be reasonably evaluated by the present method. The predicted lives were within a factor of 3 of the observed ones. (2) The present method provides the capability to predict the long term creep-fatigue life at lower temperatures as well as that at the creep dominant temperature. (3) The value of creep damage for the long term creep-fatigue data increased by elastic follow-up. The creep-fatigue damage diagram intercepted between 0.3 and 1 can represent the observed creep-fatigue damages. (4) The cavity growth depends on the hold time. The fracture of long term creep-fatigue is caused by the intergranular cavity growth. The intergranular fracture of creep-fatigue is initiated by the cavity growth and followed by the microcrack propagation along grain boundaries starting from creep cavities. (author)

  14. The Evaluation Methodology of Information Support

    Directory of Open Access Journals (Sweden)

    Lubos Necesal

    2016-01-01

    Full Text Available Knowledge, information and people are the motive force in today's organizations. Successful organizations need to find the right employees and provide them with the right and highquality information. This is a complex problem. In the world where information plays more and more important role, employees have to be skilled at information activities (searching, processing, saving, etc. of information and information system/-s (IS they work with. Organizations have to cover both these areas. Therefore, we need an effective instrument, which could be used to evaluate new employees within admission or as regular evaluating of current employees, to evaluate information system, whether it is an appropriate tool for fulfilling the employee’s tasks within the organization, and to evaluate how the organization covers the foregoing areas. Such instrument is the “Evaluation methodology of information support in organization”. This paper defines the term “information support“ and its role in organization. The body of the paper proposes the “Evaluation methodology of information support in organization”. The conclusion discusses contributions of information support evaluation

  15. Evaluation of Fatigue Crack Initiation for Volumetric Flaw in Pressure Tube

    International Nuclear Information System (INIS)

    Choi, Sung Nam; Yoo, Hyun Joo

    2005-01-01

    CAN/CSA.N285.4-94 requires the periodic inservice inspection and surveillance of pressure tubes in operating CANDU nuclear power reactors. If the inspection results reveal a flaw exceeding the acceptance criteria of the Code, the flaw must be evaluated to determine if the pressure is acceptable for continued service. Currently, the flaw evaluation methodology and acceptance criteria specified in CSA-N285.05-2005, 'Technical requirements for in-service evaluation of zirconium alloy pressure tubes in CANDU reactors'. The Code is applicable to zirconium alloy pressure tubes. The evaluation methodology for a crack-like flaw is similar to that of ASME B and PV Sec. XI, 'Inservice Inspection of Nuclear Power Plant Components'. However, the evaluation methodology for a blunt volumetric flaw is described in CSA-N285.05-2005 code. The object of this paper is to address the fatigue crack initiation evaluation for the blunt volumetric flaw as it applies to the pressure tube at Wolsong NPP

  16. A methodology for on line fatigue life monitoring : rainflow cycle counting method

    International Nuclear Information System (INIS)

    Mukhopadhyay, N.K.; Dutta, B.K.; Kushwaha, H.S.

    1992-01-01

    Green's function technique is used in on line fatigue life monitoring to convert plant data to stress versus time data. This technique converts plant data most efficiently to stress versus time data. To compute the fatigue usage factor the actual number of cycles experienced by the component is to be found out from stress versus time data. Using material fatigue properties the fatigue usage factor is to be computed from the number of cycles. Generally the stress response is very irregular in nature. To convert an irregular stress history to stress frequency spectra rainflow cycle counting method is used. This method is proved to be superior to other counting methods and yields best fatigue estimates. A code has been developed which computes the number of cycles experienced by the component from stress time history using rainflow cycle counting method. This postprocessor also computes the accumulated fatigue usage factor from material fatigue properties. The present report describes the development of a code to compute fatigue usage factor using rainflow cycle counting technique and presents a real life case study. (author). 10 refs., 10 figs

  17. Proposal of a methodology for computing damages from flexo-rotative fatigue considering the theory of the acting average stresses

    International Nuclear Information System (INIS)

    Tanius Rodrigues Mansur; Alvaro Alvarenga Junior; Joao Mario Andrade Pinto; Wellington Antonio Soares; Ernani Sales Palma

    2005-01-01

    The useful life of metallic structures is many times governed by fatigue processes caused by vibrations or by application of dynamic loads, periodic or not. Many times the amplitude of the alternated stress applied to a structural component can vary during its useful life. In this situation the direct use of S-N-P curves cannot be done because they are generated on the basis of alternated stress with constant amplitude. Several theories have been developed during the last times, where some are deterministic and other probabilistic, in order to give a component designer a more efficient and correct tool for approaching the problem. They are called Theories on Damage Accumulation. The phenomenon of creating damages represents the generation of superficial discontinuities caused by micro-cracks or by volumetric cavities [Lemaitre and Chaboche, 1985]. In the continuous mechanics, the superficial density of micro-defects (micro-cracks or cavities) inside the shear plan of the representative element volume of the sample is the variable used to quantify the damage. A methodology for evaluating damage accumulation using average of stresses is proposed in this paper. Results obtained for a 50% failure probability are presented and are compared to those values obtained using the theories of Palmgren-Miner, Henry, Corten-Dolan, Marine, Manson, and Knee-point. (authors)

  18. Study of system safety evaluation on LTO of national project. Thermal fatigue evaluation of piping systems

    International Nuclear Information System (INIS)

    Kasahara, Naoto; Itoh, Takamoto; Okazaki, Masakazu; Okuda, Yukihiko; Kamaya, Masayuki; Nakamura, Akira; Nakamura, Hitoshi; Machida, Hideo

    2012-01-01

    Nuclear piping has various kinds of thermal fatigue failure modes. Main causes of thermal loads are structural responses to fluid temperature changes during plant operation. These phenomena have complex mechanisms and so many patterns, that their problems still occur even though well-known issues. To prevent thermal fatigue due to above thermal loads, the JSME guideline is adopted. Both thermal load and fatigue failure mechanism have been investigated and summarized into the knowledgebase. Numerical simulation methods for thermal fatigue evaluation were studied to replace structural tests. Theses knowledge was utilized to validate and justify the JSME guideline. Furthermore, new studies have been launched to apply above knowledge to enhance plant system safety. (author)

  19. Unification of the methodology of competitiveness evaluation

    Directory of Open Access Journals (Sweden)

    Ivanova Marina

    2016-05-01

    Full Text Available The purpose of the study is the comparison of the modern methods of competitiveness evaluation and testing the results in practice at a production plant in order to unify the methodology. Analysis of the publications shows that the existing diversity in methods of the competitiveness evaluation complicates the choice of a method and interpretation of the results, which confirms the need to classify and unify the methods available today. The authors suggest that the standardized method of competitiveness evaluation should combine matrix and graphical methods. In our study, we have shown that SWOT-analysis should be carried out in two stages: firstly, it is necessary to determine the strengths and weaknesses of the company, taking into account the following factors: marketing, production, economic and financial situation, technology, the administration and personnel; secondly, it is essential to assess the opportunities and threats with the allowance for the political, legal, and economic situation, the impact of market as well as social, cultural and natural environmental factors. The proposed methodology of competitiveness evaluation has been tested at the industrial enterprise "Olvita ltd", which is dynamically developing and successfully operates on the food market of Ukraine; it specializes in processing, logistics and distribution of fresh and frozen vegetables, fruits and berries, as well as ready-to cook meat products. The results have shown that the competitiveness evaluation remains a pressing issue that requires simple and fairly demonstrative methods, one of which is a method that combines both graphical and matrix approaches. The advantage of the proposed method is its sufficiently high visualizations and record of personal approaches in evaluating the scores for strengths and weaknesses as well as opportunities and threats. In the future, the authors are planning to examine and systemize the indicators used in the competitiveness

  20. Individual aircraft life monitoring: An engineering approach for fatigue damage evaluation

    Directory of Open Access Journals (Sweden)

    Rui JIAO

    2018-04-01

    Full Text Available Individual aircraft life monitoring is required to ensure safety and economy of aircraft structure, and fatigue damage evaluation based on collected operational data of aircraft is an integral part of it. To improve the accuracy and facilitate the application, this paper proposes an engineering approach to evaluate fatigue damage and predict fatigue life for critical structures in fatigue monitoring. In this approach, traditional nominal stress method is applied to back calculate the S-N curve parameters of the realistic structure details based on full-scale fatigue test data. Then the S-N curve and Miner’s rule are adopted in damage estimation and fatigue life analysis for critical locations under individual load spectra. The relationship between relative small crack length and fatigue life can also be predicted with this approach. Specimens of 7B04-T74 aluminum alloy and TA15M titanium alloy are fatigue tested under two types of load spectra, and there is a good agreement between the experimental results and analysis results. Furthermore, the issue concerning scatter factor in individual aircraft damage estimation is also discussed. Keywords: Fatigue damage, Fatigue monitoring, Fatigue test, Scatter factor, S-N curve

  1. Evaluation of conservatisms and environmental effects in ASME Code, Section III, Class 1 fatigue analysis

    International Nuclear Information System (INIS)

    Deardorff, A.F.; Smith, J.K.

    1994-08-01

    This report documents the results of a study regarding the conservatisms in ASME Code Section 3, Class 1 component fatigue evaluations and the effects of Light Water Reactor (LWR) water environments on fatigue margins. After review of numerous Class 1 stress reports, it is apparent that there is a substantial amount of conservatism present in many existing component fatigue evaluations. With little effort, existing evaluations could be modified to reduce the overall predicted fatigue usage. Areas of conservatism include design transients considerably more severe than those experienced during service, conservative grouping of transients, conservatisms that have been removed in later editions of Section 3, bounding heat transfer and stress analysis, and use of the ''elastic-plastic penalty factor'' (K 3 ). Environmental effects were evaluated for two typical components that experience severe transient thermal cycling during service, based on both design transients and actual plant data. For all reasonable values of actual operating parameters, environmental effects reduced predicted margins, but fatigue usage was still bounded by the ASME Section 3 fatigue design curves. It was concluded that the potential increase in predicted fatigue usage due to environmental effects should be more than offset by decreases in predicted fatigue usage if re-analysis were conducted to reduce the conservatisms that are present in existing component fatigue evaluations

  2. Towards a Public Sector GIS Evaluation Methodology | Kurwakumire ...

    African Journals Online (AJOL)

    Towards a Public Sector GIS Evaluation Methodology. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL · RESOURCES ... However, evaluation methodologies for public sector GIS are largely lacking.

  3. Objective Evaluation of Visual Fatigue Using Binocular Fusion Maintenance.

    Science.gov (United States)

    Hirota, Masakazu; Morimoto, Takeshi; Kanda, Hiroyuki; Endo, Takao; Miyoshi, Tomomitsu; Miyagawa, Suguru; Hirohara, Yoko; Yamaguchi, Tatsuo; Saika, Makoto; Fujikado, Takashi

    2018-03-01

    In this study, we investigated whether an individual's visual fatigue can be evaluated objectively and quantitatively from their ability to maintain binocular fusion. Binocular fusion maintenance (BFM) was measured using a custom-made binocular open-view Shack-Hartmann wavefront aberrometer equipped with liquid crystal shutters, wherein eye movements and wavefront aberrations were measured simultaneously. Transmittance in the liquid crystal shutter in front of the subject's nondominant eye was reduced linearly, and BFM was determined from the transmittance at the point when binocular fusion was broken and vergence eye movement was induced. In total, 40 healthy subjects underwent the BFM test and completed a questionnaire regarding subjective symptoms before and after a visual task lasting 30 minutes. BFM was significantly reduced after the visual task ( P eye symptom score (adjusted R 2 = 0.752, P devices, such as head-mount display, objectively.

  4. Environmental Assisted Fatigue Evaluation of Direct Vessel Injection Piping Considering Thermal Stratification

    International Nuclear Information System (INIS)

    Kim, Taesoon; Lee, Dohwan

    2016-01-01

    As the environmentally assisted fatigue (EAF) due to the primary water conditions is to be a critical issue, the fatigue evaluation for the components and pipes exposed to light water reactor coolant conditions has become increasingly important. Therefore, many studies to evaluate the fatigue life of the components and pipes in LWR coolant environments on fatigue life of materials have been conducted. Among many components and pipes of nuclear power plants, the direct vessel injection piping is known to one of the most vulnerable pipe systems because of thermal stratification occurred in that systems. Thermal stratification occurs because the density of water changes significantly with temperature. In this study, fatigue analysis for DVI piping using finite element analysis has been conducted and those results showed that the results met design conditions related with the environmental fatigue evaluation of safety class 1 pipes in nuclear power plants. Structural and fatigue integrity for the DVI piping system that thermal stratification occurred during the plant operation has conducted. First of all, thermal distribution of the piping system is calculated by computational fluid dynamic analysis to analyze the structural integrity of that piping system. And the fatigue life evaluation considering environmental effects was carried out. Our results showed that the DVI piping system had enough structural integrity and fatigue life during the design lifetime of 60 years

  5. Life prediction methodology for thermal-mechanical fatigue and elevated temperature creep design

    Science.gov (United States)

    Annigeri, Ravindra

    Nickel-based superalloys are used for hot section components of gas turbine engines. Life prediction techniques are necessary to assess service damage in superalloy components resulting from thermal-mechanical fatigue (TMF) and elevated temperature creep. A new TMF life model based on continuum damage mechanics has been developed and applied to IN 738 LC substrate material with and without coating. The model also characterizes TMF failure in bulk NiCoCrAlY overlay and NiAl aluminide coatings. The inputs to the TMF life model are mechanical strain range, hold time, peak cycle temperatures and maximum stress measured from the stabilized or mid-life hysteresis loops. A viscoplastic model is used to predict the stress-strain hysteresis loops. A flow rule used in the viscoplastic model characterizes the inelastic strain rate as a function of the applied stress and a set of three internal stress variables known as back stress, drag stress and limit stress. Test results show that the viscoplastic model can reasonably predict time-dependent stress-strain response of the coated material and stress relaxation during hold times. In addition to the TMF life prediction methodology, a model has been developed to characterize the uniaxial and multiaxial creep behavior. An effective stress defined as the applied stress minus the back stress is used to characterize the creep recovery and primary creep behavior. The back stress has terms representing strain hardening, dynamic recovery and thermal recovery. Whenever the back stress is greater than the applied stress, the model predicts a negative creep rate observed during multiple stress and multiple temperature cyclic tests. The model also predicted the rupture time and the remaining life that are important for life assessment. The model has been applied to IN 738 LC, Mar-M247, bulk NiCoCrAlY overlay coating and 316 austenitic stainless steel. The proposed model predicts creep response with a reasonable accuracy for wide range of

  6. Elastic creep-fatigue evaluation for ASME [American Society of Mechanical Engineers] code

    International Nuclear Information System (INIS)

    Severud, L.K.; Winkel, B.V.

    1987-02-01

    Reassessment of past ASME N-47 creep-fatigue rules have been under way by committee members. The new proposed elastic creep-fatigue methods are easier to apply than those previously in the code case. They also provide a wider range of practical application while still providing conservative assessments. It is expected that new N-47 code rules for elastic creep-fatigue evaluation will be adopted in the near future

  7. Rotating bending fatigue strength evaluation of ceramic materials

    International Nuclear Information System (INIS)

    Govila, R.K.; Swank, L.R.

    1995-01-01

    Cyclic fatigue under rotary bending tests were conducted on partially stabilized zirconia (PSZ) from NGK and Nilsen, and silicon nitride from NGK and Norton. Fractography was performed on the failed specimens to determine the fracture structure and morphology. The results showed that the cyclic fatigue fracture was the same as the fracture structure previously observed in bending tests. The cyclic fatigue data indicated that structural ceramic could function in fatigue stress levels at a higher percentage of their average fast fracture strength than the fifty percent of ultimate strength used for wrought steels

  8. [Evaluating fatigue resistance effect of health food by near-infrared tissue oximeter].

    Science.gov (United States)

    Wu, Jian; Ding, Hai-shu; Ye, Da-tian

    2009-09-01

    Currently, chronic fatigue syndrome (CFS) seriously affects people's normal living and work. In the present paper, the physiological parameters, such as tissue oxygenation saturation and heart rate, were used to evaluate the subjects' fatigue degree, and the fatigue resistance capsule and coffee were taken as a measure to adjust the fatigue. Human tissue oxygen saturation (rSO2) can be monitored noninvasively and in real time by near infrared spectroscopy (NIRS) based on spatially-resolved spectroscopy. Aiming at those brainworkers who need to work in an office for a long time; two static experiments were designed to evaluate the fatigue degree of the subjects who either take the fatigue resistance capsules/coffee or not. The rSO2 and heart rate (HR) of the subjects in the experiment group and contrast group were measured respectively for fatigue evaluation. This work particularly analyzed the changes in rSO2 in these two groups. The results show that the rSO2 of subjects in the experiment group evidently increased compared to that in the contrast group when the subjects took the fatigue resistance capsule or coffee, thereby show that the health food can reduce the fatigue to a certain extent.

  9. Fatigue life evaluation method of austenitic stainless steel in PWR water

    International Nuclear Information System (INIS)

    Sakaguchi, Katsumi; Nomura, Yuichiro; Suzuki, Shigeki; Kanasaki, Hiroshi; Higuchi, Makoto

    2006-09-01

    It is known that the fatigue life in elevated temperature water is substantially reduced compared with that in the air. The fatigue life reduction has been investigated experimentally in EFT project of Japan Nuclear Energy Safety Organization (JNES) to evaluate the environmental effect on fatigue life. Many tests have been done for carbon, low alloy, stainless steels and nickel-based alloy under the various conditions. In this paper, the results of the stainless steel in simulated PWR water environments were reported. Fatigue life tests in simulated PWR environments were carried out and the effect of key parameters on fatigue life reduction was examined. The materials used in this study were base and weld metal of austenitic stainless steel SS316, weld metal of SS304 and the base and aged metal of the duplex stainless steel SCS14A. In order to evaluate the effects of stain amplitude, strain rate, strain ratio, temperature, aging, water flow rate and strain holding time, many fatigue tests were examined. In transient condition in an actual plant, however, such parameters as temperature and strain rate are not constant. In order to evaluate fatigue damage in actual plant on the basis of experimental results under constant temperature and strain rate condition, the modified rate approach method was developed. Various kinds of transient have to be taken into account of in actual plant fatigue evaluation, and stress cycle of several ranges of amplitude has to be considered in assessing damage from fatigue. Generally, cumulative usage factor is applied in this type of evaluation. In this study, in order to confirm the applicability of modified rate approach method together with cumulative usage factor, fatigue tests were carried out by combining stress cycle blocks of different strain amplitude levels, in which strain rate changes in response to temperature in a simulated PWR water environment. Consequently, fatigue life could be evaluated with an accuracy of factor of 3

  10. Creep, fatigue and creep-fatigue damage evaluation and estimation of remaining life of SUS 304 austenitic stainless steel at high temperature

    International Nuclear Information System (INIS)

    Nishino, Seiichi; Sakane, Masao; Ohnami, Masateru

    1986-01-01

    Experimental study was made on the damage evaluation and estimation of remaining life of SUS 304 stainless steel in creep, low-cycle fatigue and creep-fatigue at 873 K in air. Creep, fatigue and creep-fatigue damage curves were drawn by the method proposed by D.A. Woodford and the relations between these damages and non-destructive parameters, i.e., microvickers hardness and quantities obtained from X-ray diffraction, were discussed. From these tests, the following conclusions were obtained. (1) Constant damage lines in the diagram of remaining lives in creep and fatigue could be drawn by changing load levels during the tests. Constant damage lines in creep-fatigue were also made by a linear damage rule using both static creep and fatigue damage curves, which agree well with the experimental data in creep-fatigue. (2) Microvickers hardness and half-value breadth in X-ray diffraction are appropriate parameters to evaluate creep damage but are not proper to evaluate fatigue damage. Particle size and microstrain obtained by X-ray profile analysis are good parameters to evaluate both creep and fatigue damages. (author)

  11. Study on fatigue life evaluation of structural component based on crack growth criterion

    International Nuclear Information System (INIS)

    Shibata, Katsuyuki

    1984-07-01

    As one of the practical application of fracture mechanics, fatigue life evaluation method based on crack growth criterion has been diffusing in various field of technology in order to determine the rational and reliable life of structural components. The fatigue life by this method is evaluated based on the fatigue crack growth analysis from defects, while many problems, such as the influence of residual stress on the crack growth behavior, the effect of overloading, and evaluation method for multiple surface cracks, are not sufficiently solved yet. In this paper, the above problems are treated, and based on some exprimental data some simple mehtods for fatigue life evaluation are proposed regarding the above problems. Verification of the proposed methods are shown in the paper by comparing with some experimental results, and the applicability of the proposed method is also examined by the fatigue test of pipes with cracks in the inner surface. (author)

  12. Evaluating the effectiveness of using electroencephalogram power indices to measure visual fatigue.

    Science.gov (United States)

    Hsu, Bin-Wei; Wang, Mao-Jiun J

    2013-02-01

    Electroencephalography (EEG) is widely used in cognitive and behavioral research. This study evaluates the effectiveness of using the EEG power index to measure visual fatigue. Three common visual fatigue measures, critical-flicker fusion (CFF), near-point accommodation (NPA), and subjective eye-fatigue rating, were used for comparison. The study participants were 20 men with a mean age of 20.4 yr. (SD = 1.5). The experimental task was a car-racing video game. Results indicated that the EEG power indices were valid as a visual fatigue measure and the sensitivity of the objective measures (CFF and EEG power index) was higher than the subjective measure. The EEG beta and EEG alpha were effective for measuring visual fatigue in short- and long-duration tasks, respectively. EEG beta/alpha were the most effective power indexes for the visual fatigue measure.

  13. Econometric Methodology of Monopolization Process Evaluation

    Directory of Open Access Journals (Sweden)

    Dmitrijs Skoruks

    2014-06-01

    Full Text Available The research “Econometric Methodology of Monopolization Process Evaluation” gives a perspective description of monopolization process’ nature, occurrence source, development procedure and internal conjuncture specifics, as well as providing an example of modern econometrical method application within a unified framework of market competition analysis for the purpose of conducting a quantitative competition evaluation on an industry level for practical use in both private and public sectors. The main question of the aforementioned research is the definition and quantitative analysis of monopolization effects in modern day globalized markets, while con- structing an empirical model of the econometric analysis, based on the use of in- ternational historical experience of monopoly formations standings, with the goal of introducing a further development scheme for the use of both econometrical and statistical instruments in line with the forecasting and business research need of enterprises and regulatory functions of the public sector. The current research uses a vast variety of monopolization evaluation ratios and their econometrical updates on companies that are involved in the study procedure in order to detect and scallar measure their market monopolizing potential, based on the implemented acquired market positions, turnover shares and competition policies.

  14. Evaluating cyclic fatigue of sealants during outdoor testing

    Science.gov (United States)

    R. Sam Williams; Steven Lacher; Corey Halpin; Christopher White

    2009-01-01

    A computer-controlled test apparatus (CCTA) and other instrumentation for subjecting sealant specimens to cyclic fatigue during outdoor exposure was developed. The CCTA enables us to use weather-induced conditions to cyclic fatigue specimens and to conduct controlled tests in-situ during the outdoor exposure. Thermally induced dimensional changes of an aluminum bar...

  15. Evaluation of Fatigue Life of CRM-Reinforced SMA and Its Relationship to Dynamic Stiffness

    Directory of Open Access Journals (Sweden)

    Nuha Salim Mashaan

    2014-01-01

    Full Text Available Fatigue cracking is an essential problem of asphalt concrete that contributes to pavement damage. Although stone matrix asphalt (SMA has significantly provided resistance to rutting failure, its resistance to fatigue failure is yet to be fully addressed. The aim of this study is to evaluate the effect of crumb rubber modifier (CRM on stiffness and fatigue properties of SMA mixtures at optimum binder content, using four different modification levels, namely, 6%, 8%, 10%, and 12% CRM by weight of the bitumen. The testing undertaken on the asphalt mix comprises the dynamic stiffness (indirect tensile test, dynamic creep (repeated load creep, and fatigue test (indirect tensile fatigue test at temperature of 25°C. The indirect tensile fatigue test was conducted at three different stress levels (200, 300, and 400 kPa. Experimental results indicate that CRM-reinforced SMA mixtures exhibit significantly higher fatigue life compared to the mixtures without CRM. Further, higher correlation coefficient was obtained between the fatigue life and resilient modulus as compared to permanent strain; thus resilient modulus might be a more reliable indicator in evaluating the fatigue life of asphalt mixture.

  16. Evaluation of fatigue life of CRM-reinforced SMA and its relationship to dynamic stiffness.

    Science.gov (United States)

    Mashaan, Nuha Salim; Karim, Mohamed Rehan; Abdel Aziz, Mahrez; Ibrahim, Mohd Rasdan; Katman, Herda Yati; Koting, Suhana

    2014-01-01

    Fatigue cracking is an essential problem of asphalt concrete that contributes to pavement damage. Although stone matrix asphalt (SMA) has significantly provided resistance to rutting failure, its resistance to fatigue failure is yet to be fully addressed. The aim of this study is to evaluate the effect of crumb rubber modifier (CRM) on stiffness and fatigue properties of SMA mixtures at optimum binder content, using four different modification levels, namely, 6%, 8%, 10%, and 12% CRM by weight of the bitumen. The testing undertaken on the asphalt mix comprises the dynamic stiffness (indirect tensile test), dynamic creep (repeated load creep), and fatigue test (indirect tensile fatigue test) at temperature of 25°C. The indirect tensile fatigue test was conducted at three different stress levels (200, 300, and 400 kPa). Experimental results indicate that CRM-reinforced SMA mixtures exhibit significantly higher fatigue life compared to the mixtures without CRM. Further, higher correlation coefficient was obtained between the fatigue life and resilient modulus as compared to permanent strain; thus resilient modulus might be a more reliable indicator in evaluating the fatigue life of asphalt mixture.

  17. Thermal stress analysis for fatigue damage evaluation at a mixing tee

    International Nuclear Information System (INIS)

    Kamaya, Masayuki; Nakamura, Akira

    2011-01-01

    Highlights: → Thermal stress and fatigue damage have been analyzed for a mixing tee. → Fatigue damage was accumulated near boundaries of the cold spot. → It was found that fatigue damage was brought about by fluctuation of cold spot. → Simple one-dimensional analysis could derive stress for fatigue evaluation. - Abstract: Fatigue cracks have been found at mixing tees where fluids of different temperature flow in. In this study, the thermal stress at a mixing tee was calculated by the finite element method using temperature transients obtained by a fluid dynamics simulation. The simulation target was an experiment for a mixing tee, in which cold water flowed into the main pipe from a branch pipe. The cold water flowed along the main pipe wall and caused a cold spot, at which the membrane stress was relatively large. Based on the evaluated thermal stress, the magnitude of the fatigue damage was assessed according to the linear damage accumulation rule and the rain-flow procedure. Precise distributions of the thermal stress and fatigue damage could be identified. Relatively large axial stress occurred downstream from the branch pipe due to the cold spot. The variation ranges of thermal stress and fatigue damage became large near the position 20 o from the symmetry line in the circumferential direction. The position of the cold spot changed slowly in the circumferential direction, and this was the main cause of the fatigue damage. The fatigue damage was investigated for various differences in the temperature between the main and branch pipes. Since the magnitude of accumulated damage increased abruptly when the temperature difference exceeded the value corresponding to the fatigue limit, it was suggested that the stress amplitude should be suppressed less than the fatigue limit. In the thermal stress analysis for fatigue damage assessment, it was found that the detailed three-dimensional structural analysis was not required. Namely, for the current case, a one

  18. Fatigue in patients with low grade glioma: systematic evaluation of assessment and prevalence

    NARCIS (Netherlands)

    E.M.P. Van Coevorden-van Loon (Ellen M. P.); Coomans, M.B. (Marijke B.); M.H. Heijenbrok-Kal (Majanka); G.M. Ribbers (Gerard); M.J. van den Bent (Martin)

    2017-01-01

    textabstractFatigue is the most prevalent and disabling symptom in cancer patients. Yet, scientific literature on this topic is scarce and reports disparate results. This study systematically reviews how fatigue is assessed in patients with low-grade glioma and evaluates its prevalence in LGG

  19. 14 CFR 25.571 - Damage-tolerance and fatigue evaluation of structure.

    Science.gov (United States)

    2010-01-01

    ... contribute to a catastrophic failure (such as wing, empennage, control surfaces and their systems, the... TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY AIRPLANES Structure Fatigue Evaluation § 25... and sonic excitation environment, that— (1) Sonic fatigue cracks are not probable in any part of the...

  20. Muscle fatigue evaluation of astronaut upper limb based on sEMG and subjective assessment

    Science.gov (United States)

    Zu, Xiaoqi; Zhou, Qianxiang; Li, Yun

    2012-07-01

    All movements are driven by muscle contraction, and it is easy to cause muscle fatigue. Evaluation of muscle fatigue is a hot topic in the area of astronaut life support training and rehabilitation. If muscle gets into fatigue condition, it may reduce work efficiency and has an impact on psychological performance. Therefore it is necessary to develop an accurate and usable method on muscle fatigue evaluation of astronaut upper limb. In this study, we developed a method based on surface electromyography (sEMG) and subjective assessment (Borg scale) to evaluate local muscle fatigue. Fifteen healthy young male subjects participated in the experiment. They performed isometric muscle contractions of the upper limb. sEMG of the biceps brachii were recorded during the entire process of isotonic muscle contraction and Borg scales of muscle fatigue were collected in certain times. sEMG were divided into several parts, and then mean energy of each parts were calculated by the one-twelfth band octave method. Equations were derived based on the relationship between the mean energy of sEMG and Borg scale. The results showed that cubic curve could describe the degree of local muscle fatigue, and could be used to evaluate and monitor local muscle fatigue during the entire process.

  1. Evaluation methodologies for security testing biometric systems beyond technological evaluation

    OpenAIRE

    Fernández Saavedra, María Belén

    2013-01-01

    The main objective of this PhD Thesis is the specification of formal evaluation methodologies for testing the security level achieved by biometric systems when these are working under specific contour conditions. This analysis is conducted through the calculation of the basic technical biometric system performance and its possible variations. To that end, the next two relevant contributions have been developed. The first contribution is the definition of two independent biometric performance ...

  2. Optimization of Nanocomposite Modified Asphalt Mixtures Fatigue Life using Response Surface Methodology

    Science.gov (United States)

    Bala, N.; Napiah, M.; Kamaruddin, I.; Danlami, N.

    2018-04-01

    In this study, modelling and optimization of materials polyethylene, polypropylene and nanosilica for nanocomposite modified asphalt mixtures has been examined to obtain optimum quantities for higher fatique life. Response Surface Methodology (RSM) was applied for the optimization based on Box Behnken design (BBD). Interaction effects of independent variables polymers and nanosilica on fatique life were evaluated. The result indicates that the individual effects of polymers and nanosilica content are both important. However, the content of nanosilica used has more significant effect on fatique life resistance. Also, the mean error obtained from optimization results is less than 5% for all the responses, this indicates that predicted values are in agreement with experimental results. Furthermore, it was concluded that asphalt mixture design with high performance properties, optimization using RSM is a very effective approach.

  3. Methodology for evaluation of railroad technology research projects

    Science.gov (United States)

    1981-04-01

    This Project memorandum presents a methodology for evaluating railroad research projects. The methodology includes consideration of industry and societal benefits, with special attention given to technical risks, implementation considerations, and po...

  4. EVALUATION OF THE GRAI INTEGRATED METHODOLOGY AND THE IMAGIM SUPPORTWARE

    Directory of Open Access Journals (Sweden)

    J.M.C. Reid

    2012-01-01

    Full Text Available This paper describes the GRAI Integrated Methodology and identifies the need for computer tools to support enterprise modelling,design and integration. The IMAGIM tool is then evaluated in terms of its ability to support the GRAI Integrated Methodology. The GRAI Integrated Methodology is an Enterprise Integration methodology developed to support the design of CIM systems . The GRAI Integrated Methodology consists of the GRAI model and a structured approach. The latest addition to the methodology is the IMAGIM software tool developed by the GRAI research group for the specific purpose of supporting the methodology.

  5. Fatigue failure by in-line flow-induced vibration and fatigue life evaluation

    International Nuclear Information System (INIS)

    Odahara, Satoru; Murakami, Yukitaka; Inoue, Masahiro; Sueoka, Atsuo

    2004-01-01

    The phenomenon of fatigue failure by the In-line flow-induced vibration was studied. A newly water-flow-induced vibration system was made and used to reproduce fatigue failure by flow-induced vibration. A medium carbon steel specimen was fixed to the experimental equipment. A small artificial hole was introduced onto the specimen surface. Fatigue crack initiated from the artificial hole. A small portable strain histogram recorder (Mini Rainflow Corder, MRC) developed in another project of the authors' team was used to acquire the service strain hisogram at a critical point of the specimen and to measure the variation of natural frequency. Cumulative fatigue damage D defined by the Modified Miner Rule was calculated by using the strain histogram at the initial stage of test. The value of D was almost unity in the case of In-line vibration, while the values of D in the case of the Cross-flow vibration ranged from 0.2 to 0.8. (author)

  6. Overview of seismic re-evaluation methodologies

    International Nuclear Information System (INIS)

    Campbell, R.D.; Johnson, J.J.

    1993-01-01

    Several seismic licensing and safety issues have emerged over the past fifteen years for commercial U.S. Nuclear Power Plants and U.S. Government research reactors, production reactors and process facilities. The methodologies for resolution of these issues have been developed in numerous government and utility sponsored research programs. The resolution criteria have included conservative deterministic design criteria, deterministic seismic margins assessments criteria (SMA) and seismic probabilistic safety assessment criteria (SPSA). The criteria for SMAs and SPSAs have been based on realistically considering the inelastic energy absorption capability of ductile structures, equipment and piping and have incorporated the use of earthquake and testing experience to evaluate the operability of complex mechanical and electrical equipment. Most of the applications to date have been confined to the U.S. but there have been several applications to Asian, Western and Eastern Europe reactors. This paper summarizes the major issues addressed, the development of reevaluation criteria and selected applications to non U.S. reactors including WWER reactors. (author)

  7. A life evaluation under creep-fatigue-environment interaction of Ni-base wrought alloys

    International Nuclear Information System (INIS)

    Hattori, Hiroshi; Kitagawa, Masaki; Ohtomo, Akira; Itoh, Mitsuyoshi

    1986-01-01

    In order to determine a failure criteria under cyclic loading and affective environment for HTGR systems, a series of strain controlled low-cycle fatigue tests were carried out at HTGR maximum gas temperatures in air, in vacuum and in HTGR helium environments on two nickel-base wrought alloys, namely Inconel 617 and Hastelloy XR. This paper first describes the creep-fatigue-environment properties of these alloys followed by a proposal of an evaluation method of creep-fatigue-environment interaction based on the experimental data to define the more reasonable design criteria, which is a modification of the linear damage summation rule. Second, the creep-fatigue properties of Hastelloy XR at 900 deg C and the result evaluated by this proposed method are shown. This criterion is successfully applied to the life prediction at 900 deg C. In addition, the creep-fatigue properties of Hastelloy XR-II are discussed. (author)

  8. A methodology for spectral wave model evaluation

    Science.gov (United States)

    Siqueira, S. A.; Edwards, K. L.; Rogers, W. E.

    2017-12-01

    Model evaluation is accomplished by comparing bulk parameters (e.g., significant wave height, energy period, and mean square slope (MSS)) calculated from the model energy spectra with those calculated from buoy energy spectra. Quality control of the observed data and choice of the frequency range from which the bulk parameters are calculated are critical steps in ensuring the validity of the model-data comparison. The compared frequency range of each observation and the analogous model output must be identical, and the optimal frequency range depends in part on the reliability of the observed spectra. National Data Buoy Center 3-m discus buoy spectra are unreliable above 0.3 Hz due to a non-optimal buoy response function correction. As such, the upper end of the spectrum should not be included when comparing a model to these data. Bioufouling of Waverider buoys must be detected, as it can harm the hydrodynamic response of the buoy at high frequencies, thereby rendering the upper part of the spectrum unsuitable for comparison. An important consideration is that the intentional exclusion of high frequency energy from a validation due to data quality concerns (above) can have major implications for validation exercises, especially for parameters such as the third and fourth moments of the spectrum (related to Stokes drift and MSS, respectively); final conclusions can be strongly altered. We demonstrate this by comparing outcomes with and without the exclusion, in a case where a Waverider buoy is believed to be free of biofouling. Determination of the appropriate frequency range is not limited to the observed spectra. Model evaluation involves considering whether all relevant frequencies are included. Guidance to make this decision is based on analysis of observed spectra. Two model frequency lower limits were considered. Energy in the observed spectrum below the model lower limit was calculated for each. For locations where long swell is a component of the wave

  9. Evaluation and assessment of nuclear power plant seismic methodology

    Energy Technology Data Exchange (ETDEWEB)

    Bernreuter, D.; Tokarz, F.; Wight, L.; Smith, P.; Wells, J.; Barlow, R.

    1977-03-01

    The major emphasis of this study is to develop a methodology that can be used to assess the current methods used for assuring the seismic safety of nuclear power plants. The proposed methodology makes use of system-analysis techniques and Monte Carlo schemes. Also, in this study, we evaluate previous assessments of the current seismic-design methodology.

  10. Evaluation and assessment of nuclear power plant seismic methodology

    International Nuclear Information System (INIS)

    Bernreuter, D.; Tokarz, F.; Wight, L.; Smith, P.; Wells, J.; Barlow, R.

    1977-01-01

    The major emphasis of this study is to develop a methodology that can be used to assess the current methods used for assuring the seismic safety of nuclear power plants. The proposed methodology makes use of system-analysis techniques and Monte Carlo schemes. Also, in this study, we evaluate previous assessments of the current seismic-design methodology

  11. Development of nondestructive evaluation of creep-fatigue damage in SUS316 stainless steel

    International Nuclear Information System (INIS)

    Shoji, Tetsuo; Kawahara, Tetsuji; Awano, Masakazu; Sato, Yasumoto

    1999-01-01

    Creep-fatigue is a fatal failure mode of high temperature structural materials. It is recognized that the law of linear damage, according to which creep-fatigue damage is expressed by the sum of the creep damage and the fatigue damage, is inadequate to evaluate creep-fatigue damage. This is due to the fact that the law of linear damage does not include the effect of interaction between the creep damage and the fatigue damage. Consequently, development of direct measurement of damage accumulation on the sample of interest is required for plant life evaluation. In this study, the induced current focusing potential drop (ICFPD) technique was used to evaluate the depth of small surface cracks in SUS316FR stainless steel which was subjected to creep-fatigue damage. It is shown that the potential drop increased during the micro-crack initiation and propagation. Correspondingly, the ICFPD technique applied to estimate micro-crack depth changes was used to accurately evaluate the residual life of creep-fatigue damaged structural materials. (author)

  12. Fatigue performance evaluation of selective laser melted Ti–6Al–4V

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, P. [Boeing Research and Technology, The Boeing Company, Seattle, WA (United States); Ramulu, M., E-mail: ramulum@u.washington.edu [Department of Mechanical Engineering, University of Washington, Seattle, WA (United States)

    2014-03-01

    Additive Manufacturing of titanium components holds promise to deliver benefits such as reduced cost, weight and carbon emissions during both manufacture and use. To capitalize on these benefits, it must be shown that the mechanical performance of parts produced by Additive Manufacturing can meet design requirements that are typically based on wrought material performance properties. Of particular concern for safety critical structures are the fatigue properties of parts produced by Additive Manufacturing. This research evaluates the fatigue properties of Ti–6Al–4V specimens produced by the Selective Laser Melting additive manufacturing process. It was found that the fatigue life is significantly lower compared to wrought material. This reduction in fatigue performance was attributed to a variety of issues, such as microstructure, porosity, surface finish and residual stress. There was also found to be a high degree of anisotropy in the fatigue performance associated with the specimen build orientation.

  13. Fatigue performance evaluation of selective laser melted Ti–6Al–4V

    International Nuclear Information System (INIS)

    Edwards, P.; Ramulu, M.

    2014-01-01

    Additive Manufacturing of titanium components holds promise to deliver benefits such as reduced cost, weight and carbon emissions during both manufacture and use. To capitalize on these benefits, it must be shown that the mechanical performance of parts produced by Additive Manufacturing can meet design requirements that are typically based on wrought material performance properties. Of particular concern for safety critical structures are the fatigue properties of parts produced by Additive Manufacturing. This research evaluates the fatigue properties of Ti–6Al–4V specimens produced by the Selective Laser Melting additive manufacturing process. It was found that the fatigue life is significantly lower compared to wrought material. This reduction in fatigue performance was attributed to a variety of issues, such as microstructure, porosity, surface finish and residual stress. There was also found to be a high degree of anisotropy in the fatigue performance associated with the specimen build orientation

  14. Fatigue after stroke: the development and evaluation of a case definition.

    Science.gov (United States)

    Lynch, Joanna; Mead, Gillian; Greig, Carolyn; Young, Archie; Lewis, Susan; Sharpe, Michael

    2007-11-01

    While fatigue after stroke is a common problem, it has no generally accepted definition. Our aim was to develop a case definition for post-stroke fatigue and to test its psychometric properties. A case definition with face validity and an associated structured interview was constructed. After initial piloting, the feasibility, reliability (test-retest and inter-rater) and concurrent validity (in relation to four fatigue severity scales) were determined in 55 patients with stroke. All participating patients provided satisfactory answers to all the case definition probe questions demonstrating its feasibility For test-retest reliability, kappa was 0.78 (95% CI, 0.57-0.94, Pdefinition also had substantially higher fatigue scores on four fatigue severity scales (Pvalidity. The proposed case definition is feasible to administer and reliable in practice, and there is evidence of concurrent validity. It requires further evaluation in different settings.

  15. Evaluation of fatigue damage in nuclear power plants: evolution and new tools of analysis

    International Nuclear Information System (INIS)

    Cicero, R.; Corchon, F.

    2011-01-01

    This paper presents new fatigue mechanisms requiring analysis, tools developed for evaluation and the latest trends and studies that are currently working in the nuclear field, and allow proper management referring facilities the said degradation mechanism.

  16. Fatigue Evaluation of Recycled Asphalt Mixture Based on Energy-Controlled Mode

    Directory of Open Access Journals (Sweden)

    Tao Ma

    2017-01-01

    Full Text Available The fatigue properties of asphalt mixtures are important inputs for mechanistic-empirical pavement design. To understand the fatigue properties of asphalt mixtures better and to predict the fatigue life of asphalt mixtures more precisely, the energy-controlled test mode was introduced. Based on the implementation theory, the laboratory practice for the energy-controlled mode was realized using a four-point-bending fatigue test with multiple-step loading. In this mode, the fatigue performance of typical AC-20 asphalt specimens with various reclaimed asphalt pavement (RAP contents was tested and evaluated. Results show that the variation regulation of the dissipated energy and accumulative energy is compatible with the loading control principle, which proves the feasibility of the method. In addition, the fatigue life of the asphalt mixture in the energy-controlled mode was between that for the stress-controlled and strain-controlled modes. The specimen with a higher RAP content has a longer fatigue life and better fatigue performance.

  17. Calculation and evaluation methodology of the flawed pipe and the compute program development

    International Nuclear Information System (INIS)

    Liu Chang; Qian Hao; Yao Weida; Liang Xingyun

    2013-01-01

    Background: The crack will grow gradually under alternating load for a pressurized pipe, whereas the load is less than the fatigue strength limit. Purpose: Both calculation and evaluation methodology for a flawed pipe that have been detected during in-service inspection is elaborated here base on the Elastic Plastic Fracture Mechanics (EPFM) criteria. Methods: In the compute, the depth and length interaction of a flaw has been considered and a compute program is developed per Visual C++. Results: The fluctuating load of the Reactor Coolant System transients, the initial flaw shape, the initial flaw orientation are all accounted here. Conclusions: The calculation and evaluation methodology here is an important basis for continue working or not. (authors)

  18. Development of thermal fatigue evaluation methods of piping systems

    International Nuclear Information System (INIS)

    Kasahara, Naoto; Itoh, Takamoto; Okazaki, Masakazu; Okuda, Yukihiko; Kamaya, Masayuki; Nakamura, Akira; Nakamura, Hitoshi; Machida, Hideo; Matsumoto, Masaaki

    2014-01-01

    Nuclear piping has various kinds of thermal fatigue failure modes. Main causes of thermal loads are structural responses to fluid temperature changes during plant operation. These phenomena have complex mechanisms and many patterns, so that their problems still occur in spite of well-known issues. The guideline of the JSME (Japan Society of Mechanical Engineering) for estimation of thermal fatigue failures in piping system is employed as Japanese regulation. To improve this guideline, generation mechanisms of thermal load and fatigue failure have been investigated and summarized into the knowledgebase. And numerical simulation methods to replace experimental based methods were studied. Furthermore, probabilistic failure analysis approach with main influence parameters was investigated to be applied for the plant system safety. Thus, based on the knowledge, estimation methods revised from the JSME guideline were proposed. (author)

  19. Consistent creep and rupture properties for creep-fatigue evaluation

    International Nuclear Information System (INIS)

    Schultz, C.C.

    1978-01-01

    The currently accepted practice of using inconsistent representations of creep and rupture behaviors in the prediction of creep-fatigue life is shown to introduce a factor of safety beyond that specified in current ASME Code design rules for 304 stainless steel Class 1 nuclear components. Accurate predictions of creep-fatigue life for uniaxial tests on a given heat of material are obtained by using creep and rupture properties for that same heat of material. The use of a consistent representation of creep and rupture properties for a mininum strength heat is also shown to provide adequate predictions. The viability of using consistent properties (either actual or those of a minimum heat) to predict creep-fatigue life thus identifies significant design uses for the results of characterization tests and improved creep and rupture correlations

  20. Consistent creep and rupture properties for creep-fatigue evaluation

    International Nuclear Information System (INIS)

    Schultz, C.C.

    1979-01-01

    The currently accepted practice of using inconsistent representations of creep and rupture behaviors in the prediction of creep-fatigue life is shown to introduce a factor of safety beyond that specified in current ASME Code design rules for 304 stainless steel Class 1 nuclear components. Accurate predictions of creep-fatigue life for uniaxial tests on a given heat of material are obtained by using creep and rupture properties for that same heat of material. The use of a consistent representation of creep and rupture properties for a minimum strength heat is also shown to provide reasonable predictions. The viability of using consistent properties (either actual or those of a minimum strength heat) to predict creep-fatigue life thus identifies significant design uses for the results of characterization tests and improved creep and rupture correlations. 12 refs

  1. The Meaning and Measurement of Work Fatigue: Development and Evaluation of the Three-Dimensional Work Fatigue Inventory (3D-WFI)

    Science.gov (United States)

    Frone, Michael R.; Tidwell, Marie-Cecile O.

    2015-01-01

    Although work fatigue represents an important construct in several substantive areas, prior conceptual definitions and measures have been inadequate in a number of ways. The goals of the present study were to develop a conceptual definition and outline the desirable characteristics of a work fatigue measure; briefly examine several prior measures of work fatigue-related constructs; and develop and evaluate a new measure of work fatigue. The Three-Dimensional Work Fatigue Inventory (3D-WFI) provides separate and commensurate assessments of physical, mental, and emotional work fatigue. Results from a pilot study (N = 207) and a broader evaluative study of U.S. wage and salary workers (N = 2,477) suggest that the 3D-WFI is psychometrically sound and evinces a meaningful pattern of relations with variables that comprise the nomological network of work fatigue. As with all new measures, additional research is required to evaluate fully the utility of the 3D-WFI in research on work fatigue. PMID:25602275

  2. Methodology of evaluation of value created in the productive processes

    OpenAIRE

    M.T. Roszak

    2008-01-01

    Purpose: Of this paper was to present the methodology of analysis of the productive processes with applicationof value analysis and multi-criterion-analysis which allow to evaluate the technology and organization of theproductive processes.Design/methodology/approach: Presented in the paper methodology of evaluation of the productive processesis based on analysis of activities in the productive processes and their characteristics with reference to createdvalue in the productive chain.Findings...

  3. Creep-fatigue damage evaluation for SS-316LN (ORNL PLATES): - RCC-MR vs. ASME SEC III - NH

    International Nuclear Information System (INIS)

    Sati, Bhuwan Chandra; Jalaldeen, S.; Velusamy, K.; Selvaraj, P.

    2016-01-01

    Investigations of high temperature tests done on ORNL plate with deformation control loading, under creep-fatigue damage have been presented. The test results with methodology of RCC-MR and ASME-NH life prediction under creep-fatigue loading have been assessed. The stress relaxation effect in calculating the life using RCC-MR under creep-fatigue damage is found to be significant in presence of secondary stress. RCC-MR: 2007 is more realistic number of cycles (predicts 51 number of cycles) as compared to ASME-NH (predicts 312 number of cycles) which is demonstrated by the experimental work (observed 86 numbers of cycles). Between RCC-MR and experimental work, design code seems to be more conservative for life prediction due to creep-fatigue damage. For fatigue damage, the approaches are same and the difference comes from material properties and the starting stress for applying Neuber's rule. ASME approach has the limitation of stress range magnitude. ASME approach predicts lower elastic plus plastic strain for the cases having S* above the linear stress limit. For creep strain and creep damage evaluation, ASME and RCC-MR have different approaches for calculating the stress at the beginning and during the hold period. The RCC-MR takes account of cyclic hardening or softening effects (hardening in the present case of 316 LN) by means of the cyclic stress-strain curve and the benefit of symmetrization effects which are significant for this material. The ASME code neglects these effects and instead relies on an approach based on the isochronous stress-strain curves. (author)

  4. Fatigue assessments in operating nuclear power plants

    International Nuclear Information System (INIS)

    Gosselin, S.R.; Deardorff, A.F.; Peltola, D.W.

    1994-01-01

    In November 1991, the ASME Section XI Task Group on Operating Plant Fatigue Assessment was formed to develop criteria and evaluation methodology for evaluating the effects of cyclic operation in operating nuclear power plants. The objective was to develop guidelines for inclusion in Section XI that could be used by plant operators in evaluating fatigue concerns and their impact on serviceability. This paper discusses the work performed by the Task Group. It explores the concept of ''Fatigue Design Basis'' versus ''Fatigue Operating Basis'' by examining the roles of ASME Section III and ASME Section XI in the design and operation of the nuclear power plants. Guidelines are summarized that may help plant operators perform effective design transient cycle evaluations and optimize cycle counting and fatigue usage tracking. The alternative fatigue evaluation approach using flaw tolerance is also introduced

  5. Experimental evaluation of torsional fatigue strength of welded bellows and application to design of fusion device

    International Nuclear Information System (INIS)

    Takatsu, Hideyuki; Yamamoto, Masahiro; Shimizu, Masatsugu; Suzuki, Kazuo; Sonobe, Tadashi; Hayashi, Yuzo; Mizuno, Gen-ichiro.

    1984-01-01

    Torsional fatigue strength of the welded bellows was evaluated experimentally, aiming the application to a port of a fusion device. The welded bellows revealed elastic torsional buckling and spiral distorsion even under a small angle of torsion. Twisting load never leads the welded bellows to fracture easily so far as the angle of torsion is not excessively large, and the welded bellows has the torsional fatigue strength much larger than that expected so far. Two formulae were proposed to evaluate the stress of the welded bellows under the forced angle of torsion; shearing stress evaluation formula in the case that torsional buckling does not occur and the axial bending stress evaluation formula in the case that torsional buckling occurs. And the results of the torsional fatigue experiments showed that the former is reasonably conservative and simulates the actual behavior of the welded bellows better than the latter in the high cycle fatigue region and vice versa in the low cycle fatigue region from the viewpoint of the mechanical design. The present evaluation method of the torsional fatigue strength was applied to the welded bellows for the port of the JT-60 vacuum vessel and its structural integrity was confirmed under the design load condition. (author)

  6. Stress Optical Coefficient, Test Methodology, and Glass Standard Evaluation

    Science.gov (United States)

    2016-05-01

    ARL-TN-0756 ● MAY 2016 US Army Research Laboratory Stress Optical Coefficient, Test Methodology , and Glass Standard Evaluation...Stress Optical Coefficient, Test Methodology , and Glass Standard Evaluation by Clayton M Weiss Oak Ridge Institute for Science and Education...ORISE), Belcamp, MD Parimal J Patel Weapons and Materials Research Directorate, ARL Approved for public release; distribution is

  7. Evaluation Methodologies for Estimating the Likelihood of Program Implementation Failure

    Science.gov (United States)

    Durand, Roger; Decker, Phillip J.; Kirkman, Dorothy M.

    2014-01-01

    Despite our best efforts as evaluators, program implementation failures abound. A wide variety of valuable methodologies have been adopted to explain and evaluate the "why" of these failures. Yet, typically these methodologies have been employed concurrently (e.g., project monitoring) or to the post-hoc assessment of program activities.…

  8. Environmentally assisted fatigue evaluation model of alloy 690 steam generator tube in high temperature water

    International Nuclear Information System (INIS)

    Tan Jibo; Wu Xinqiang; Han Enhou; Wang Xiang; Liu Xiaoqiang; Xu Xuelian

    2015-01-01

    Nickel-based alloy 690 has been widely used as steam generator tube in light water reactor (LWR) nuclear power plants, which may suffer from corrosion fatigue during long-term service. Many researches and operating experience indicated that the effect of LWR environment could significantly reduce the fatigue life of structural materials. However. such an environmental degradation effect was not fully addressed in the current ASME code design fatigue curves. Therefore, the Regulatory Guide 1.207 issued by US NRC required a new NPP have to incorporate the environment effects into fatigue analyses. In the last few decades, researchers in USA and Japan systematically investigated the corrosion fatigue behavior of nuclear-grade structural materials in LWR environment. Then, ANL model and JSME model were proposed, which incorporated environmental effects, including temperature, dissolved oxygen (DO) and strain rate for the nickel-based alloys. Due to lack of experiment data on domestic materials, there is no related environmental fatigue design model in China. In the present work, based on the corrosion fatigue tests of a kind of boat-shaped specimen in borated and lithiated high temperature water, the corrosion fatigue behavior and environmentally assisted cracking mechanism of domestic Alloy 690 steam generator tube have been investigate. An IMR model for the nickel-based alloy was proposed. The environmental fatigue life correction factor (F en ) was established, which addressed the environmental factors, including temperature, strain rate and dissolved oxygen. The method to evaluate environmental fatigue damage of structural materials in NPPs was proposed. (authors)

  9. Development of methodology for evaluating and monitoring steam generator feedwater nozzle cracking in PWRs

    International Nuclear Information System (INIS)

    Shvarts, S.; Gerber, D.A.; House, K.; Hirschberg, P.

    1994-01-01

    The objective of this paper is to describe a methodology for evaluating and monitoring steam generator feedwater nozzle cracking in PWR plants. This methodology is based in part on plant test data obtained from a recent Diablo Canyon Power Plant (DCPP) Unit 1 heatup. Temperature sensors installed near the nozzle-to-pipe weld were monitored during the heatup, along with operational parameters such as auxiliary feedwater (AFW) flow rate and steam generator temperature. A thermal stratification load definition was developed from this data. Steady state characteristics of this data were used in a finite element analysis to develop relationship between AFW flow and stratification interface level. Fluctuating characteristics of this data were used to determine transient parameters through the application of a Green's Function approach. The thermal stratification load definition from the test data was used in a three-dimensional thermal stress analysis to determine stress cycling and consequent fatigue damage or crack growth during AFW flow fluctuations. The implementation of the developed methodology in the DCPP and Sequoyah Nuclear Plant (SNP) fatigue monitoring systems is described

  10. An Evaluation Methodology for Protocol Analysis Systems

    Science.gov (United States)

    2007-03-01

    Main Memory Requirement NS: Needham-Schroeder NSL: Needham-Schroeder-Lowe OCaml : Objective Caml POSIX: Portable Operating System...methodology is needed. A. PROTOCOL ANALYSIS FIELD As with any field, there is a specialized language used within the protocol analysis community. Figure...ProVerif requires that Objective Caml ( OCaml ) be installed on the system, OCaml version 3.09.3 was installed. C. WINDOWS CONFIGURATION OS

  11. Fatigue damage evaluation of austenitic stainless steel using nonlinear ultrasonic waves in low cycle regime

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jianfeng; Xuan, Fu-Zhen, E-mail: fzxuan@ecust.edu.cn [MOE Key Laboratory of Pressurized System and Safety, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237 (China)

    2014-05-28

    The interrupted low cycle fatigue test of austenitic stainless steel was conducted and the dislocation structure and fatigue damage was evaluated subsequently by using both transmission electron microscope and nonlinear ultrasonic wave techniques. A “mountain shape” correlation between the nonlinear acoustic parameter and the fatigue life fraction was achieved. This was ascribed to the generation and evolution of planar dislocation structure and nonplanar dislocation structure such as veins, walls, and cells. The “mountain shape” correlation was interpreted successfully by the combined contribution of dislocation monopole and dipole with an internal-stress dependent term of acoustic nonlinearity.

  12. EVALUATION OF METHODS FOR ESTIMATING FATIGUE PROPERTIES APPLIED TO STAINLESS STEELS AND ALUMINUM ALLOYS

    Directory of Open Access Journals (Sweden)

    Taylor Mac Intyer Fonseca Junior

    2013-12-01

    Full Text Available This work evaluate seven estimation methods of fatigue properties applied to stainless steels and aluminum alloys. Experimental strain-life curves are compared to the estimations obtained by each method. After applying seven different estimation methods at 14 material conditions, it was found that fatigue life can be estimated with good accuracy only by the Bäumel-Seeger method for the martensitic stainless steel tempered between 300°C and 500°C. The differences between mechanical behavior during monotonic and cyclic loading are probably the reason for the absence of a reliable method for estimation of fatigue behavior from monotonic properties for a group of materials.

  13. 75 FR 11799 - Fatigue Tolerance Evaluation of Metallic Structures

    Science.gov (United States)

    2010-03-12

    ... rotorcraft components including, but not limited to, rotors, rotor drive systems between the engines and the main and tail rotor hubs, controls, fuselage, fixed and movable control surfaces, engine and.... About that same time, rotorcraft manufacturers were introducing advanced composite materials for fatigue...

  14. Fatigue strength evaluation of friction stir welded aluminium joints using the nominal and notch stress concepts

    International Nuclear Information System (INIS)

    Barsoum, Z.; Khurshid, M.; Barsoum, I.

    2012-01-01

    Highlights: ► Fatigue testing and evaluation of friction stir welded butt and overlap joints. ► Evaluation based on nominal and effective notch stress concept. ► Comparison with different design recommendations and codes. ► Higher fatigue strength and SN-slopes is observed. ► New fatigue design recommendations proposed for FSW joints. -- Abstract: In this study the fatigue strength is investigated for Friction Stir Welded (FSW) overlap and butt welded joints in different thicknesses based on nominal and effective notch stress concepts. The fatigue test results are compared with fatigue strength recommendations according to EN 1999-1-3 and International Institute of Welding (IIW). The results are also compared with available published data and Finite Element Analysis (FEA) is carried out to investigate the effect of plate thickness and nugget size on the fatigue strength of overlap joints. 3–3 mm butt welded joints shows the highest fatigue strength in comparison with 3–5 mm butt welded and overlap joints. Slopes of the SN-curves for two different joint types differ from the slope recommended by IIW. A specific failure trend is observed in overlap FSW joints. However, the slopes of the SN-curves are in close agreement with slopes found in EN 1999-1-3. The slopes of various published results and test results presented in this study are in good agreement with each other. The suggested fatigue design curves for the nominal and effective notch stress concept have a higher slope than given for fusion welds by IIW.

  15. Environmental factor approach to account for water effects in pressure vessel and piping fatigue evaluations

    International Nuclear Information System (INIS)

    Mehta, H.S.; Gosselin, S.R.

    1998-01-01

    This paper summarizes past and current studies of the environmental fatigue effects in light water reactor (LWR) applications. Current Argonne and Japanese research efforts are reviewed and an approach to calculate an environmental correction factor is described. A description of how the proposed approach can be implemented in section III, NB-3600 and NB-3200-type fatigue evaluations is presented along with examples of applying the approach to piping (NB-3600) and safe end fatigue evaluations. These procedures were applied to several BWR and pressurized water reactor (PWR) example cases. The results of these case studies indicated that there is a modest increase in calculated fatigue usage, which is considerably less than the results obtained when the NUREG/CR-5999 curves are applied directly. (orig.)

  16. Profiled Roller Stress/Fatigue Life Analysis Methodology and Establishment of an Appropriate Stress/Life Exponent

    Science.gov (United States)

    1997-01-01

    The objective of this work was to determine the three dimensional volumetric stress field, surface pressure distribution and actual contact area between a 0.50" square roller with different crown profiles and a flat raceway surface using Finite Element Analysis. The 3-dimensional stress field data was used in conjunction with several bearing fatigue life theories to extract appropriate values for stress-life exponents. Also, results of the FEA runs were used to evaluate the laminated roller model presently used for stress and life prediction.

  17. Creating and evaluating a new clicker methodology

    Science.gov (United States)

    Li, Pengfei

    "Clickers", an in-class polling system, has been used by many instructors to add active learning and formative assessment to previously passive traditional lectures. While considerable research has been conducted on clicker increasing student interaction in class, less research has been reported on the effectiveness of using clicker to help students understand concepts. This thesis reported a systemic project by the OSU Physics Education group to develop and test a new clicker methodology. Clickers question sequences based on a constructivist model of learning were used to improve classroom dynamics and student learning. They also helped students and lecturers understand in real time whether a concept had been assimilated or more effort was required. Chapter 1 provided an introduction to the clicker project. Chapter 2 summarized widely-accepted teaching principles that have arisen from a long history of research and practice in psychology, cognitive science and physics education. The OSU clicker methodology described in this thesis originated partly from our years of teaching experience, but mostly was based on these teaching principles. Chapter 3 provided an overview of the history of clicker technology and different types of clickers. Also, OSU's use of clickers was summarized together with a list of common problems and corresponding solutions. These technical details may be useful for those who want to use clickers. Chapter 4 discussed examples of the type and use of question sequences based on the new clicker methodology. In several years of research, we developed a base of clicker materials for calculus-based introductory physics courses at OSU. As discussed in chapter 5, a year-long controlled quantitative study was conducted to determine whether using clickers helps students learn, how using clickers helps students learn and whether students perceive that clicker has a positive effect on their own learning process. The strategy for this test was based on

  18. Research methodological issues in evaluating herbal interventions

    Directory of Open Access Journals (Sweden)

    Dipika Bansal

    2010-02-01

    Full Text Available Dipika Bansal, Debasish Hota, Amitava ChakrabartiPostgraduate Institute of Medical Education and Research, Chandigarh, IndiaAbstract: Randomized controlled trials provide the best evidence, and is seen as the gold standard for allopathic research. Herbal therapies are not an integral part of conventional care although they are still used by patients in their health care management. These medicines need to be subjected to rigorous research to establish their effectiveness and safety. Clearly defined treatments are required and should be recorded in a manner that enables other suitably trained researchers to reproduce them reliably. Quality control of herbal products is also a prerequisite of credible clinical trials. Methodological strategies for investigating the herbal interventions and the issues regarding appropriate patient selection, randomization and blinding, placebo effects and choice of comparator, occupational standardization and the selection of appropriate study endpoints to prove efficacy are being discussed. This paper will review research options and propose some suggestions for future research design.Keywords: CAM research, herbal therapies, methodology, clinical trial

  19. Evaluation of proliferation resistance using the INPRO methodology

    International Nuclear Information System (INIS)

    Yang, Myung Seung; Park, Joo Hwan; Ko, Won Il; Song, Kee Chan; Choi, Kun Mo; Kim, Jin Kyoung

    2007-01-01

    The IAEA launched the International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO) and developed the INPRO Methodology to provide guidelines and to assess the characteristics of a future innovative nuclear energy system in areas such as safety, economics, waste management, and proliferation resistance. The proliferation resistance area of the INPRO Methodology is reviewed here, and modifications for further improvements are proposed. The evaluation metrics including the evaluation parameters, evaluation scales and acceptance limits are developed for a practical application of the methodology to assess the proliferation resistance. The proliferation resistant characteristics of the DUPIC fuel cycle are assessed by applying the modified INPRO Methodology based on the developed evaluation metrics and acceptance criteria. The evaluation procedure and the metrics can be utilized as a reference for an evaluation of the proliferation resistance of a future innovative nuclear energy system

  20. Effects of photobiomodulation on the fatigue level in elderly women: an isokinetic dynamometry evaluation.

    Science.gov (United States)

    Vassão, P G; Toma, R L; Antunes, H K M; Tucci, H T; Renno, A C M

    2016-02-01

    Aging is responsible by a series of morphological and functional modifications that lead to a decline of muscle function, particularly in females. Muscle tissue in elderly people is more susceptible to fatigue and, consequently, to an increased inability to maintain strength and motor control. In this context, therapeutic approaches able of attenuating muscle fatigue have been investigated. Among these, the photobiomodulation demonstrate positive results to interacts with biological tissues, promoting the increase in cell energy production. Thus, the aim of this study was to investigate the effects of photobiomodulation (808 nm, 250 J/cm(2), 100 mW, 7 J each point) in the fatigue level and muscle performance in elderly women. Thirty subjects entered a crossover randomized double-blinded placebo-controlled trial. Photobiomodulation was delivered on the rectus femoris muscle of the dominant limb immediately before the fatigue protocol. In both sessions, peripheral muscle fatigue was analyzed by surface electromyography (EMG) and blood lactate analysis. Muscle performance was evaluated using an isokinetic dynamometer. The results showed that photobiomodulation was able of reducing muscle fatigue by a significant increase of electromyographic fatigue index (EFI) (p = 0.047) and decreasing significantly lactate concentration 6 min after the performance of the fatigue protocol (p = 0. 0006) compared the placebo laser session. However, the photobiomodulation was not able of increasing muscle performance measured by the isokinetic dynamometer. Thus, it can be conclude that the photobiomodulation was effective in reducing fatigue levels. However, no effects of photobiomodulation on muscle performance was observed.

  1. Development of a Physically-Based Methodology for Predicting Material Variability in Fatigue Crack Initiation and Growth Response

    National Research Council Canada - National Science Library

    Chan, Kwai

    2004-01-01

    ... of aerospace structural alloys. In this three-year program, physics-based fatigue crack initiation and growth models were developed and integrated into a probabilistic micromechanical code for treating fatigue life variability...

  2. Evaluation procedure of creep-fatigue defect growth in high temperature condition and application

    International Nuclear Information System (INIS)

    Park, Chang Gyu; Kim, Jong Bum; Lee, Jae Han

    2003-12-01

    This study proposed the evaluation procedure of creep-fatigue defect growth on the high-temperature cylindrical structure applicable to the KALIMER, which is developed by KAERI. Parameters used in creep defect growth and the evaluation codes with these parameters were analyzed. In UK, the evaluation procedure of defect initiation and growth were proposed with R5/R6 code. In Japan, simple evauation method was proposed by JNC. In France, RCC-MR A16 code which was evaluation procedure of the creep-fatigue defect initiation and growth related to leak before break was developed, and equations related to load conditions were modified lately. As an application example, the creep-fatigue defect growth on circumferential semi-elliptical surface defect in high temperature cylindrical structure was evaluated by RCC-MR A16

  3. Visual Fatigue Evaluation: Improvement of Reflected Glare on Touch Screen for Nuclear Power Plant

    International Nuclear Information System (INIS)

    Liu, Kang Hung; Yang, Chih Wei; Hwang, Sheue Ling; Liou, Jin Liang

    2014-01-01

    The purpose of this research is to evaluate the visual fatigue of operators caused by glare problems in the main control room of nuclear power plant. Within the limitation in the main control room, reflectors were set under the light source which generates reflected glare on touch screens. Through avoiding the light directly shines on touch screens, reflected glare were eliminated. This research matched up the setting process of reflectors, evaluated the visual fatigue of operators, and collected user's opinions before reflector setting, after the first setting, and after the second setting. The design of reflectors could refer the result of evaluations and the collection of opinions. Nevertheless, the improvement of reflected glare on touch screens could be verified by this evaluations. The result showed that setting reflectors under the light source could eliminate reflected glare effectively, and the visual fatigue was reduced both on subject and object evaluations. However, the setting direction of reflectors has potential effect on operators' visual fatigue, so the real setting of reflectors still need to be evaluated completely. The near point accommodation could reflect the effect of visual fatigue caused by changes of lighting environment. Thus, the verification of new lighting environment according to the near point accommodation is suggested

  4. Safeguards Automated Facility Evaluation (SAFE) methodology

    International Nuclear Information System (INIS)

    Chapman, L.D.; Grady, L.M.; Bennett, H.A.; Sasser, D.W.; Engi, D.

    1978-08-01

    An automated approach to facility safeguards effectiveness evaluation has been developed. This automated process, called Safeguards Automated Facility Evaluation (SAFE), consists of a collection of a continuous stream of operational modules for facility characterization, the selection of critical paths, and the evaluation of safeguards effectiveness along these paths. The technique has been implemented on an interactive computer time-sharing system and makes use of computer graphics for the processing and presentation of information. Using this technique, a comprehensive evaluation of a safeguards system can be provided by systematically varying the parameters that characterize the physical protection components of a facility to reflect the perceived adversary attributes and strategy, environmental conditions, and site operational conditions. The SAFE procedure has broad applications in the nuclear facility safeguards field as well as in the security field in general. Any fixed facility containing valuable materials or components to be protected from theft or sabotage could be analyzed using this same automated evaluation technique

  5. Fatigue evaluation for the socket weld in nuclear power plants

    International Nuclear Information System (INIS)

    Choi, Young Hwan; Choi, Sun Yeong; Huh, Nam Soo

    2004-01-01

    The operating experience showed that the fatigue is one of the major piping failure mechanisms in nuclear power plants (NPPs). The pressure and/or temperature loading transients, the vibration, and the mechanical cyclic loading during the plant operation may induce the fatigue failure in the nuclear piping. Recently, many fatigue piping failure occurred at the socket weld area have been widely reported. Many failure cases showed that the gap requirement between the pipe and fitting in the socket weld was not satisfied though the ASME Code Sec. Requires 1/16 inch gap in the socket weld. The ASME Code OM also limits the vibration level of the piping system, but some failure cases showed the limitation was not satisfied during the plant operation. In this paper, the fatigue behavior of the socket weld in the nuclear piping was estimated by using the three dimensional finite element method. The results are as follows. The socket weld is susceptible to the vibration if the vibration levels exceed the requirement in the ASME Code OM. The effect of the pressure or temperature transient load on the socket weld in NPPs is not significant because of the very low frequency of the transient during the plant lifetime operation. 'No gap' is very risky to the socket weld integrity for the specific systems having the vibration condition to exceed the requirement in the ASME OM Code and/or the transient loading condition. The reduction of the weld leg size from 1.09 * t 1 to 0.75 * t 1 can affect severely on the socket weld integrity

  6. Impact evaluation of rolling contact fatigue life models

    International Nuclear Information System (INIS)

    Choi, Young Sik; Yang, Xiaoping

    2012-01-01

    Since the accurate prediction of fatigue life has a significant value, many researchers have attempted to develop a reliable fatigue life model. Recently, rolling contact fatigue life models incorporating machining impact were developed. These models have contributed to a significant improvement in prediction accuracy as compared with earlier models, thus representing a major step forward in the modeling effort. This paper compares the prediction accuracy of these models with that of the prediction method in International Standards. When α is set to 0.25, the observed improvement of prediction accuracy as measured by variance of prediction errors due to these models over that due to prediction method in International Standards is statistically significant. Impact analyses of such improvement are conducted to illustrate its value. It is further noted that while difference was observed between the variance of prediction errors due to the crack initiation life model based on a dislocation model and that due to the crack initiation life model based on a local stress-life curve, the observed difference is not statistically significant

  7. A dissipated energy comparison to evaluate fatigue resistance using 2-point bending

    Directory of Open Access Journals (Sweden)

    Cinzia Maggiore

    2014-02-01

    Full Text Available Fatigue is the main failure mode in pavement engineering. Typically, micro-cracks originate at the bottom of asphalt concrete layer due to horizontal tensile strains. Micro-cracks start to propagate towards the upper layers under repeated loading which can lead to pavement failure. Different methods are usually used to describe fatigue behavior in asphalt materials such as: phenomenological approach, fracture mechanics approach and dissipated energy approach. This paper presents a comparison of fatigue resistances calculated for different dissipated energy models using 2-point bending (2PB at IFSTTAR in Nantes. 2PB tests have been undertaken under different loading and environmental conditions in order to evaluate the properties of the mixtures (stiffness, dissipated energy, fatigue life and healing effect.

  8. Comparing methodologies for structural identification and fatigue life prediction of a highway bridge

    OpenAIRE

    Pai, Sai Ganesh Sarvotham; Nussbaumer, Alain; Smith, Ian F. C.

    2018-01-01

    Accurate measurement-data interpretation leads to increased understanding of structural behavior and enhanced asset-management decision making. In this paper, four data-interpretation methodologies, residual minimization, traditional Bayesian model updating, modified Bayesian model updating (with an L∞-norm-based Gaussian likelihood function), and error-domain model falsification (EDMF), a method that rejects models that have unlikely differences between predictions and measurements, are comp...

  9. Comparing Structural Identification Methodologies for Fatigue Life Prediction of a Highway Bridge

    OpenAIRE

    Pai, Sai G.S.; Nussbaumer, Alain; Smith, Ian F.C.

    2018-01-01

    Accurate measurement-data interpretation leads to increased understanding of structural behavior and enhanced asset-management decision making. In this paper, four data-interpretation methodologies, residual minimization, traditional Bayesian model updating, modified Bayesian model updating (with an L∞-norm-based Gaussian likelihood function), and error-domain model falsification (EDMF), a method that rejects models that have unlikely differences between predictions and measurements, are comp...

  10. Evaluation of an energy-based fatigue approach considering mean stress effects

    Energy Technology Data Exchange (ETDEWEB)

    Kabir, S. M. Humayun [Chittagong University of Engineering and Technology, Chittagong (Bangladesh); Yeo, Tae In [University of Ulsan, Ulsan (Korea, Republic of)

    2014-04-15

    In this paper, an attempt is made to extend the total strain energy approach for predicting the fatigue life subjected to mean stress under uniaxial state. The effects of means stress on the fatigue failure of a ferritic stainless steel and high pressure tube steel are studied under strain-controlled low cycle fatigue condition. Based on the fatigue results from different strain ratios, modified total strain energy density approach is proposed to account for the mean stress effects. The proposed damage parameter provides convenient means of evaluating fatigue life with mean stress effects considering the fact that the definitions used for measuring strain energies are the same as in the fully-reversed cycling (R = -1). A good agreement is observed between experimental life and predicted life using proposed approach. Two other mean stress models (Smith-Watson-Topper model and Morrow model) are also used to evaluate the low cycle fatigue data. Based on a simple statistical estimator, the proposed approach is compared with these models and is found realistic.

  11. Fatigue evaluation for Tsing Ma Bridge using structural health monitoring data

    Science.gov (United States)

    Chan, Hung-tin Tommy; Ko, Jan Ming; Li, Zhao-Xia

    2001-08-01

    Fatigue assessment for the Tsing Ma Bridge (TMB) are presented based on the British standard BS5400 and the real-time structural health monitoring data under railway loading. TMB, as an essential portion of transport network for the Hong Kong airport, is the longest suspension bridge in the world carrying both highway and railway traffic. The bridge design has been mainly based on BS5400. A structural health monitoring system - Wind and Structural Health Monitoring System (WASHMS) for TMB has been operated since the bridge commissioning in May 1997. In order to assess the fatigue behavior of TMB under railway loading, strain gauges were installed on the bridge deck to measure the strain-time histories as soon as the bridge is loaded by a standard railway loading due to the service of an actual train. The strain-time history data at the critical members are then used to determine the stress spectrum, of which the rainflow method recommended for railway bridges by BS5400 is applied to count cycles of stress range. Miner's law is employed to evaluate fatigue damage and remaining service life of the bridge. The evaluated results of fatigue damage and remaining service life would help us to well understand about the fatigue design of the bridge and status in fatigue accumulation.

  12. Evaluation of an energy-based fatigue approach considering mean stress effects

    International Nuclear Information System (INIS)

    Kabir, S. M. Humayun; Yeo, Tae In

    2014-01-01

    In this paper, an attempt is made to extend the total strain energy approach for predicting the fatigue life subjected to mean stress under uniaxial state. The effects of means stress on the fatigue failure of a ferritic stainless steel and high pressure tube steel are studied under strain-controlled low cycle fatigue condition. Based on the fatigue results from different strain ratios, modified total strain energy density approach is proposed to account for the mean stress effects. The proposed damage parameter provides convenient means of evaluating fatigue life with mean stress effects considering the fact that the definitions used for measuring strain energies are the same as in the fully-reversed cycling (R = -1). A good agreement is observed between experimental life and predicted life using proposed approach. Two other mean stress models (Smith-Watson-Topper model and Morrow model) are also used to evaluate the low cycle fatigue data. Based on a simple statistical estimator, the proposed approach is compared with these models and is found realistic.

  13. Safeguards Automated Facility Evaluation (SAFE) methodology

    International Nuclear Information System (INIS)

    Chapman, L.D.; Grady, L.M.; Bennett, H.A.; Sasser, D.W.; Engi, D.

    1978-01-01

    The SAFE procedure is an efficient method of evaluating the physical protection system of a nuclear facility. Since the algorithms used in SAFE for path generation and evaluation are analytical, many paths can be evaluated with a modest investment in computer time. SAFE is easy to use because the information required is well-defined and the interactive nature of this procedure lends itself to straightforward operation. The modular approach that has been taken allows other functionally equivalent modules to be substituted as they become available. The SAFE procedure has broad applications in the nuclear facility safeguards field as well as in the security field in general. Any fixed facility containing valuable materials or components to be protected from theft or sabotage could be analyzed using this same automated evaluation technique

  14. Seismic fatigue life evaluation of mechanical structures using energy balance equation

    International Nuclear Information System (INIS)

    Minagawa, Keisuke; Fujita, Satoshi; Kitamura, Seiji; Okamura, Shigeki

    2009-01-01

    Evaluation of seismic resistant performance for severe earthquakes is required, because of occurrence of earthquakes which exceed the design criteria. Additionally, quantitative evaluation of cumulative damage by earthquake is also required. In this study, the energy balance equation is applied to the evaluation. The energy balance equation expresses integral information of response, so that the energy balance equation is adequate for the evaluation of the influence of cumulative load such as seismic response. At first, vibration experiment that leads experimental model to fatigue failure by continuous vibration disturbance is conducted. As a result of the experiment, relation between fatigue failure and energy balance equation is confirmed. Then the relation is proved from the viewpoint of hysteresis energy, and consistency between energy balance equation and hysteresis energy is confirmed. Finally, we adopted cumulative damage rule to energy balance equation in order to expect the fatigue life under random waves that have various input acceleration. (author)

  15. Evaluation methodology for generator refurbishment decisions

    International Nuclear Information System (INIS)

    Moore, W.G.; Ulm, S.F.

    1991-01-01

    The Electrical Power Industry is undergoing tremendous change due to deregulation, aging equipment, environmental concerns, and investment/risk considerations. Public utility commissions, along with shareholders and end consumers, are closely monitoring utilities; decisions, especially in the area of costs-both Operation and Maintenance, and Capital. Increasing emphasis, within the conventional utility environment, has been and continue to be, placed on controlling expenditures. To be responsive to these industry and competitive pressures, utilities must make equipment refurbishment decisions. These decisions should be based on input from many sources, including the severity of the failure, cost of replacement versus refurbishment, risks and safety considerations, the expected remaining life of the unit, operational mode (base or peak), fuel type, initial costs, system capacity, available budgets, and financing options. Many times, however, refurbishment decisions are base don an abstract understanding of the above, but feel, or emotional attachment to a particular option. This paper describes a general methodology for refurbishment decision making, applied specifically to generators. Also included in a case history of one utility's progression through this process

  16. Fault-tolerant architecture: Evaluation methodology

    International Nuclear Information System (INIS)

    Battle, R.E.; Kisner, R.A.

    1992-08-01

    The design and reliability of four fault-tolerant architectures that may be used in nuclear power plant control systems were evaluated. Two architectures are variations of triple-modular-redundant (TMR) systems, and two are variations of dual redundant systems. The evaluation includes a review of methods of implementing fault-tolerant control, the importance of automatic recovery from failures, methods of self-testing diagnostics, block diagrams of typical fault-tolerant controllers, review of fault-tolerant controllers operating in nuclear power plants, and fault tree reliability analyses of fault-tolerant systems

  17. An economic analysis methodology for project evaluation and programming.

    Science.gov (United States)

    2013-08-01

    Economic analysis is a critical component of a comprehensive project or program evaluation methodology that considers all key : quantitative and qualitative impacts of highway investments. It allows highway agencies to identify, quantify, and value t...

  18. Present stage evaluation of Furnas calculus methodology qualification

    International Nuclear Information System (INIS)

    1987-07-01

    This technical note is about the present stage evaluation of FURNAS Calculus Methodology Qualification related to reload licensing process and licensing support of operation questions of Angra 1 NPP concerning transient and Core ThermalHydraulic areas. (Author) [pt

  19. Methodology for Evaluating Encapsulated Beneficial Uses of Coal Combustion Residuals

    Science.gov (United States)

    The primary purpose of this document is to present an evaluation methodology developed by the EPA for making determinations about environmental releases from encapsulated products containing coal combustion residuals.

  20. Fatigue life evaluation of 42CrMo4 nitrided steel by local approach: Equivalent strain-life-time

    International Nuclear Information System (INIS)

    Terres, Mohamed Ali; Sidhom, Habib

    2012-01-01

    Highlights: → Ion nitriding treatment of 42CrMo4 steel improves their fatigue strength by 32% as compared with the untreated state. → This improvement is the result of the beneficial effects of the superficial work- hardening and of the stabilized compressive residual stress. → The notch region is found to be the fatigue crack nucleation site resulting from a stress concentration (Kt = 1.6). → The local equivalent strain-fatigue life method was found to be an interesting predictive fatigue life method for nitrided parts. -- Abstract: In this paper, the fatigue resistance of 42CrMo4 steel in his untreated and nitrided state was evaluated, using both experimental and numerical approaches. The experimental assessment was conducted using three points fatigue flexion tests on notched specimens at R = 0.1. Microstructure analysis, micro-Vickers hardness test, and scanning electron microscope observation were carried out for evaluating experiments. In results, the fatigue cracks of nitrided specimens were initiated at the surface. The fatigue life of nitrided specimens was prolonged compared to that of the untreated. The numerical method used in this study to predict the nucleation fatigue life was developed on the basis of a local approach, which took into account the applied stresses and stabilized residual stresses during the cyclic loading and the low cyclic fatigue characteristics. The propagation fatigue life was calculated using fracture mechanics concepts. It was found that the numerical results were well correlated with the experimental ones.

  1. Evaluation of fatigue damage of pressure vessel materials by observation of microstructures

    International Nuclear Information System (INIS)

    Yoshida, Kazuo

    1994-01-01

    As the important factor as the secular change mode of pressure vessel materials, there is fatigue damage. In USA, there is the move to use LWRs by extending their life, and it becomes necessary to show the soundness of the structures of machinery and equipment for long period. For exactly evaluating the soundness of the structures of machinery and equipment, it is important to clarify the degree of secular deterioration of the materials. In this report, by limiting to the fatigue damage of LWR pressure vessel steel, the method of grasping the change of microstructure and the method of estimating the degree of fatigue damage from the change of microstructure are shown. The change of microstructure arising in materials due to fatigue advances in the following steps, namely, the multiplication of dislocations, the tangling of dislocations, the formation of cell structure, the turning of cells, the formation of microcracks, the growth of cracks and fracture. In the case of pressure vessel steel, due to the quenching and tempering, the cell structure is formed from the beginning, and the advance of fatigue is recognized as the increase of the turning angle of cell structures. The detection of fatigue damage by microstructure is reported. (K.I.)

  2. Interviewing: Methodological Briefs - Impact Evaluation No. 12

    OpenAIRE

    Bronwen McDonald; Patricia Rogers

    2014-01-01

    Interviews are easy to do badly and hard to do well - good planning, adequate time and appropriate skills are required. The type of interview should be carefully chosen to suit the situation rather than choosing a type of interview (such as focus groups) simply because it is commonly used. Interviews with children raise particular ethical issues that need to be carefully considered and fully addressed. This brief outlines key issues to consider in planning interviews for impact evaluation, ta...

  3. An Evaluation of Aviation Maintenance Fatigue Countermeasures Training

    Science.gov (United States)

    2013-05-01

    oamtechreports 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price Unclassified...water 50.0 38.5* Taking walks 42.9 28.6 Eating multiple meals or snacks 28.6 14.3 Avoiding exercise hours before bed 46.2* 30.8* Doing strength...Light snacks at breaks (1) *Of the six attendees who reported previously receiving fatigue training/education, one also reported changing behaviors at

  4. Evaluation of hot hardness, creep, fatigue and fracture properties of zirconia ceramics by an indentation technique

    International Nuclear Information System (INIS)

    Kutty, T.R.G.; Ganguly, C.; Upadhyaya, D.D.

    1996-01-01

    Zirconia ceramics have wide range engineering applications at room and elevated temperatures. For understanding the mechanical behaviour, the indentation technique was adapted for quick evaluation of hot hardness, creep, fatigue and fracture properties. A Vicker's diamond indentor with 10 N load was employed for hot hardness and creep measurement up to 1300 deg. The fatigue data were evaluated at room temperature by repeated indentation with a constant load (10-2500N) at the same location for a dwell time of 5s until it resulted in the formation of a lateral chip on the sample surface. Thus, the number of cycles for chip formation at a specific indentation load was obtained. The fracture toughness was evaluated at room temperature with a load of 300N using a Vicker's diamond indentor. The results of hot hardness, creep, fatigue, and fracture data ol 3Y-TZP and Mg-PSZ are discussed along with their microstructural features. (authors)

  5. Fatigue evaluation of the API specification 12F shop welded flat bottom tanks

    International Nuclear Information System (INIS)

    Rondon, A.; Guzey, S.

    2017-01-01

    Shop-built storage tanks are widely used in several industries all over the world. These equipment are fabricated with relatively small dimensions and capacities to facilitate their transportation to production fields. Particularly, API 12F shop-welded, flat bottom tanks are a group of standard equipment with specific sizes and capacities that are commonly used in the upstream, exploration, and production segments of oil and gas projects. The extensive utilization of this equipment has raised the need to investigate their behavior under different load cases and determine their service life due to cyclic loading. Throughout this investigation, a fatigue evaluation was performed following the guidelines of the ASME BPVC Section VIII, Division 2, design-by-analysis rules. The thirteen API 12F tanks were separated in three different groups according to their diameters. Also, different thicknesses as well as pressure cycles including internal pressure and vacuum were considered for the evaluation of each group. An elastic stress analysis using finite elements was conducted on shell models, axisymmetric models and solid submodels to determine the stress components and stress tensor range as well as obtain the effective alternating equivalent stress. Moreover, the fatigue penalty factor and a fatigue strength reduction factor were defined in accordance with the ASME code specifications. Hence, the protection against failure from cyclic loading of these equipment was determined using smooth bar design fatigue curves and the permissible number of operational cycles and location of the most critical joint were computed for each API 12F tank. - Highlights: • Stress analysis was performed following the ASME design-by-analysis. • Storage tanks axisymmetric and solid finite element models were developed. • Smooth bar design fatigue curve was obtained to perform the fatigue evaluation. • Clean out juncture is critical for the fatigue life of API 12F tanks. • Smaller

  6. Cross-cultural adaptation and psychometric evaluations of the Turkish version of Parkinson Fatigue Scale.

    Science.gov (United States)

    Ozturk, Erhan Arif; Kocer, Bilge Gonenli; Umay, Ebru; Cakci, Aytul

    2018-06-07

    The objectives of the present study were to translate and cross-culturally adapt the English version of the Parkinson Fatigue Scale into Turkish, to evaluate its psychometric properties, and to compare them with that of other language versions. A total of 144 patients with idiopathic Parkinson disease were included in the study. The Turkish version of Parkinson Fatigue Scale was evaluated for data quality, scaling assumptions, acceptability, reliability, and validity. The questionnaire response rate was 100% for both test and retest. The percentage of missing data was zero for items, and the percentage of computable scores was full. Floor and ceiling effects were absent. The Parkinson Fatigue Scale provides an acceptable internal consistency (Cronbach's alpha was 0.974 for 1st test and 0.964 for a retest, and corrected item-to-total correlations were ranged from 0.715 to 0.906) and test-retest reliability (Cohen's kappa coefficients were ranged from 0.632 to 0.786 for individuals items, and intraclass correlation coefficient was 0.887 for the overall Parkinson Fatigue Scale Score). An exploratory factor analysis of the items revealed a single factor explaining 71.7% of variance. The goodness-of-fit statistics for the one-factorial confirmatory factor analysis were Tucker Lewis index = 0.961, comparative fit index = 0.971 and root mean square error of approximation = 0.077 for a single factor. The average Parkinson Fatigue Scale Score was correlated significantly with sociodemographic data, clinical characteristics and scores of rating scales. The Turkish version of the Parkinson Fatigue Scale seems to be culturally well adapted and have good psychometric properties. The scale can be used in further studies to assess the fatigue in patients with Parkinson's disease.

  7. Empirical evaluation and justification of methodologies in psychological science.

    Science.gov (United States)

    Proctor, R W; Capaldi, E J

    2001-11-01

    The purpose of this article is to describe a relatively new movement in the history and philosophy of science, naturalism, a form of pragmatism emphasizing that methodological principles are empirical statements. Thus, methodological principles must be evaluated and justified on the same basis as other empirical statements. On this view, methodological statements may be less secure than the specific scientific theories to which they give rise. The authors examined the feasibility of a naturalistic approach to methodology using logical and historical analysis and by contrasting theories that predict new facts versus theories that explain already known facts. They provide examples of how differences over methodological issues in psychology and in science generally may be resolved using a naturalistic, or empirical, approach.

  8. Physical protection evaluation methodology program development and application

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Janghoon; Yoo, Hosik [Korea Institute of Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of)

    2015-10-15

    It is essential to develop a reliable physical protection evaluation methodology for applying physical protection concept to the design stage. The methodology can be used to assess weak points and improve performance not only for the design stage but also for nuclear facilities in operation. Analyzing physical protection property of nuclear facilities is not a trivial work since there are many interconnected factors affecting overall performance. Therefore several international projects have been organized to develop a systematic physical protection evaluation methodology. INPRO (The International Project on Innovative Nuclear Reactors and Fuel Cycles) and GIF PRPP (Generation IV International Forum Proliferation Resistance and Physical Protection) methodology are among the most well-known evaluation methodologies. INPRO adopts a checklist type of questionnaire and has a strong point in analyzing overall characteristic of facilities in a qualitative way. COMPRE program has been developed to help general users apply COMPRE methodology to nuclear facilities. In this work, COMPRE program development and a case study of the hypothetical nuclear facility are presented. The development of COMPRE program and a case study for hypothetic facility is presented in this work. The case study shows that COMPRE PP methodology can be a useful tool to assess the overall physical protection performance of nuclear facilities. To obtain meaningful results from COMPRE PP methodology, detailed information and comprehensive analysis are required. Especially, it is not trivial to calculate reliable values for PPSE (Physical Protection System Effectiveness) and C (Consequence), while it is relatively straightforward to evaluate LI (Legislative and Institutional framework), MC (Material Control) and HR (Human Resources). To obtain a reliable PPSE value, comprehensive information about physical protection system, vital area analysis and realistic threat scenario assessment are required. Like

  9. Physical protection evaluation methodology program development and application

    International Nuclear Information System (INIS)

    Seo, Janghoon; Yoo, Hosik

    2015-01-01

    It is essential to develop a reliable physical protection evaluation methodology for applying physical protection concept to the design stage. The methodology can be used to assess weak points and improve performance not only for the design stage but also for nuclear facilities in operation. Analyzing physical protection property of nuclear facilities is not a trivial work since there are many interconnected factors affecting overall performance. Therefore several international projects have been organized to develop a systematic physical protection evaluation methodology. INPRO (The International Project on Innovative Nuclear Reactors and Fuel Cycles) and GIF PRPP (Generation IV International Forum Proliferation Resistance and Physical Protection) methodology are among the most well-known evaluation methodologies. INPRO adopts a checklist type of questionnaire and has a strong point in analyzing overall characteristic of facilities in a qualitative way. COMPRE program has been developed to help general users apply COMPRE methodology to nuclear facilities. In this work, COMPRE program development and a case study of the hypothetical nuclear facility are presented. The development of COMPRE program and a case study for hypothetic facility is presented in this work. The case study shows that COMPRE PP methodology can be a useful tool to assess the overall physical protection performance of nuclear facilities. To obtain meaningful results from COMPRE PP methodology, detailed information and comprehensive analysis are required. Especially, it is not trivial to calculate reliable values for PPSE (Physical Protection System Effectiveness) and C (Consequence), while it is relatively straightforward to evaluate LI (Legislative and Institutional framework), MC (Material Control) and HR (Human Resources). To obtain a reliable PPSE value, comprehensive information about physical protection system, vital area analysis and realistic threat scenario assessment are required. Like

  10. Economic evaluation in stratified medicine: methodological issues and challenges

    Directory of Open Access Journals (Sweden)

    Hans-Joerg eFugel

    2016-05-01

    Full Text Available Background: Stratified Medicine (SM is becoming a practical reality with the targeting of medicines by using a biomarker or genetic-based diagnostic to identify the eligible patient sub-population. Like any healthcare intervention, SM interventions have costs and consequences that must be considered by reimbursement authorities with limited resources. Methodological standards and guidelines exist for economic evaluations in clinical pharmacology and are an important component for health technology assessments (HTAs in many countries. However, these guidelines have initially been developed for traditional pharmaceuticals and not for complex interventions with multiple components. This raises the issue as to whether these guidelines are adequate to SM interventions or whether new specific guidance and methodology is needed to avoid inconsistencies and contradictory findings when assessing economic value in SM.Objective: This article describes specific methodological challenges when conducting health economic (HE evaluations for SM interventions and outlines potential modifications necessary to existing evaluation guidelines /principles that would promote consistent economic evaluations for SM.Results/Conclusions: Specific methodological aspects for SM comprise considerations on the choice of comparator, measuring effectiveness and outcomes, appropriate modelling structure and the scope of sensitivity analyses. Although current HE methodology can be applied for SM, greater complexity requires further methodology development and modifications in the guidelines.

  11. Randomized Evaluation of Cognitive-Behavioral Therapy and Graded Exercise Therapy for Post-Cancer Fatigue.

    Science.gov (United States)

    Sandler, Carolina X; Goldstein, David; Horsfield, Sarah; Bennett, Barbara K; Friedlander, Michael; Bastick, Patricia A; Lewis, Craig R; Segelov, Eva; Boyle, Frances M; Chin, Melvin T M; Webber, Kate; Barry, Benjamin K; Lloyd, Andrew R

    2017-07-01

    Cancer-related fatigue is prevalent and disabling. When persistent and unexplained, it is termed post-cancer fatigue (PCF). Cognitive behavioral therapy (CBT) and graded exercise therapy (GET) may improve symptoms and functional outcomes. To evaluate the outcomes of a randomized controlled trial, which assigned patients with post-cancer fatigue to education, or 12 weeks of integrated cognitive-behavioral therapy (CBT) and graded exercise therapy (GET). Three months after treatment for breast or colon cancer, eligible patients had clinically significant fatigue, no comorbid medical or psychiatric conditions that explained the fatigue, and no evidence of recurrence. The CBT/GET arm included individually tailored consultations at approximately two weekly intervals. The education arm included a single visit with clinicians describing the principles of CBT/GET and a booklet. The primary outcome was clinically significant improvement in self-reported fatigue (Somatic and Psychological HEalth REport 0-12), designated a priori as greater than one SD of improvement in fatigue score. The secondary outcome was associated improvement in function (role limitation due to physical health problems-36-Item Short Form Health Survey 0-100) comparing baseline, end treatment (12 weeks), and follow-up (24 weeks). There were 46 patients enrolled, including 43 women (94%), with a mean age of 51 years. Fatigue severity improved in all subjects from a mean of 5.2 (±3.1) at baseline to 3.9 (±2.8) at 12 weeks, suggesting a natural history of improvement. Clinically significant improvement was observed in 7 of 22 subjects in the intervention group compared with 2 of 24 in the education group (P < 0.05, χ 2 ). These subjects also had improvement in functional status compared with nonresponders (P < 0.01, t-test). Combined CBT/GET improves fatigue and functional outcomes for a subset of patients with post-cancer fatigue. Further studies to improve the response rate and the magnitude of

  12. Evaluation of safeguards procedures: a summary of a methodology

    International Nuclear Information System (INIS)

    Salisbury, J.D.; Savage, J.W.

    1979-01-01

    A methodology for the evaluation of safeguards procedures is described. As presently conceptualized, the methodology will consist of the following steps: (1) expansion of the general protection requirements that are contained in the NRC regulations into more detailed but still generic requirements for use at the working level; (2) development of techniques and formats for using the working-level requirements in an evaluation; (3) development of a technique for converting specific facility protection procedures into a format that will allow comparison with the working-level requirements; (4) development of an evaluation technique for comparing the facility protection procedures to determine if they meet the protection requirements

  13. Evaluation of fatigue cracks using nonlinearities of acousto-ultrasonic waves acquired by an active sensor network

    International Nuclear Information System (INIS)

    Zhou, Chao; Hong, Ming; Su, Zhongqing; Wang, Qiang; Cheng, Li

    2013-01-01

    There has been increasing interest in using the nonlinear features of acousto-ultrasonic (AU) waves to detect damage onset (e.g., micro-fatigue cracks) due to their high sensitivity to damage with small dimensions. However, most existing approaches are able to infer the existence of fatigue damage qualitatively, but fail to further ascertain its location and severity. A damage characterization approach, in conjunction with the use of an active piezoelectric sensor network, was established, capable of evaluating fatigue cracks in a quantitative manner (including the co-presence of multiple fatigue cracks, and their individual locations and severities). Fundamental investigations, using both experiment and enhanced finite element analysis dedicated to the simulation of nonlinear AU waves, were carried out to link the accumulation of nonlinearities extracted from high-order AU waves to the characteristic parameters of a fatigue crack. A probability-based diagnostic imaging algorithm was developed, facilitating an intuitive presentation of identification results in images. The approach was verified experimentally by evaluating multi-fatigue cracks near rivet holes of a fatigued aluminum plate, showing satisfactory precision in characterizing real, barely visible fatigue cracks. Compared with existing methods, this approach innovatively (i) uses permanently integrated active sensor networks, conducive to automatic and online health monitoring; (ii) characterizes fatigue cracks at a quantitative level; (iii) allows detection of multiple fatigue cracks; and (iv) visualizes identification results in intuitive images. (paper)

  14. Flaw tolerance as an alternative approach for operating plant fatigue evaluation

    International Nuclear Information System (INIS)

    Deardorff, A.F.; Riccardella, P.C.

    1994-01-01

    In the design of Class 1 components for nuclear reactors, the ASME Boiler and Pressure Vessel Code requires that the suitability for cyclic operation be addressed to assure a fatigue-resistant design. During plant operation, the acceptability of the component may come in to question if new types of loading conditions are identified or if the number of plant cycles exceeds that considered in the original design. The most common approach for addressing this issue is by performing a revised fatigue evaluation, consistent with that considered in the original design. This paper presents an alternative approach for demonstrating acceptability for continued service using concepts from fracture mechanics

  15. Evaluation of fatigue crack growth and fracture resistance of SA350 LF2 material

    International Nuclear Information System (INIS)

    Singh, P.K.; Dubey, J.S.; Chakrabarty, J.K.; Vaze, K.K.; Kushwaha, H.S.

    2003-01-01

    The aim of the present paper is to evaluate the tensile and fracture mechanics properties of the SA350 LF2 carbon steel material used as the Header material in the primary heat transport (PHT) system piping of the Indian pressurized heavy water reactors (PHWR). Tensile, fatigue crack growth rate and fracture toughness tests have been carried out on specimens machined from the Header of the actual PHT pipes. The effect of temperature on tensile properties has been discussed. The effect of temperature and notch orientation on fracture resistance behavior of the material and fatigue crack growth rate dependence on the notch orientation and stress ratio has also been discussed. (author)

  16. A Real-time Evaluation Technique of Fatigue Damage in Adhesively Bonded Composite-Metal Joints

    International Nuclear Information System (INIS)

    Kwon, Oh Yang; Kim, Tae Hyun

    1999-01-01

    One of the problems for practical use of fiber-reinforced plastics is the performance degradation by fatigue damage in the joints. The study is to develop a nondestructive technique for real-time evaluation of adhesively bonded composite-metal joints. From the prior study we confirmed that the bonding strength can be estimated from the correlation between the qualify of bonded parts and AUP's. We obtained a curve showing the correlation between the degree of fatigue damage and AUP's calculated from signals acquired during fatigue loading of single-lap and double-lap joints of CFRP and Al6061. The curve is an analogy to the one showing stiffness reduction (E/Eo) of polymer matrix composites by fatigue damage. From those facts, it is plausible to predict the degree of fatigue damage in real-time. Amplitude and AUP2 appeared to be optimal parameters to provide more reliable results for single-lap joints whereas Amplitude and AUP2 did for double-lap joints. It is recommended to select optimal parameters for different geometries in the application for real structures

  17. A Real-time Evaluation Technique of Fatigue Damage in Adhesively Bonded Composite-Metal Joints

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Oh Yang; Kim, Tae Hyun [Inha University, Incheon (Korea, Republic of)

    1999-12-15

    One of the problems for practical use of fiber-reinforced plastics is the performance degradation by fatigue damage in the joints. The study is to develop a nondestructive technique for real-time evaluation of adhesively bonded composite-metal joints. From the prior study we confirmed that the bonding strength can be estimated from the correlation between the qualify of bonded parts and AUP's. We obtained a curve showing the correlation between the degree of fatigue damage and AUP's calculated from signals acquired during fatigue loading of single-lap and double-lap joints of CFRP and Al6061. The curve is an analogy to the one showing stiffness reduction (E/Eo) of polymer matrix composites by fatigue damage. From those facts, it is plausible to predict the degree of fatigue damage in real-time. Amplitude and AUP2 appeared to be optimal parameters to provide more reliable results for single-lap joints whereas Amplitude and AUP2 did for double-lap joints. It is recommended to select optimal parameters for different geometries in the application for real structures

  18. Evaluation of cyclic flexural fatigue of M-wire nickel-titanium rotary instruments.

    Science.gov (United States)

    Al-Hadlaq, Solaiman M S; Aljarbou, Fahad A; AlThumairy, Riyadh I

    2010-02-01

    This study was conducted to investigate cyclic flexural fatigue resistance of GT series X rotary files made from the newly developed M-wire nickel-titanium alloy compared with GT and Profile nickel-titanium files made from a conventional nickel-titanium alloy. Fifteen files, size 30/0.04, of each type were used to evaluate the cyclic flexural fatigue resistance. A simple device was specifically constructed to measure the time each file type required to fail under cyclic flexural fatigue testing. The results of this experiment indicated that the GT series X files had superior cyclic flexural fatigue resistance than the other 2 file types made from a conventional nickel-titanium alloy (P = .004). On the other hand, the difference between the Profile and the GT files was not statistically significant. The findings of this study suggest that size 30/0.04 nickel-titanium rotary files made from the newly developed M-wire alloy have better cyclic flexural fatigue resistance than files of similar design and size made from the conventional nickel-titanium alloy. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Study on creep-fatigue evaluation of chrome-molybdenum steel

    International Nuclear Information System (INIS)

    Aoto, Kazumi; Wada, Yusaku

    1993-01-01

    Though chrome-molybdenum steel has quite different basic material properties from austenitic stainless steel, the life fraction rule based on an advanced ductility exhaustion theory proposed for SUS304 is able to give proper prediction for creep-fatigue life of chrome-molybdenum steel. The applicability of the present evaluation method to chrome-molybdenum steel is validated by both mechanical study and micro-structural observation. The mechanism of creep-fatigue failure of Mod.9Cr-1Mo(NT) is one of the most controversial subjects among researchers. However, it is clarified in this report that creep-fatigue damage of this material under actual loading conditions is dominated by creep-cavitation of grain boundaries as same way as that of austenitic stainless steel. Furthermore, for the life reduction of low cycle fatigue of chrome-molybdenum steel with compression-side strain hold, both effects of mean stress and oxide-wedge are denied and it is insisted that the acceleration of fatigue-crack propagation is occurred by oxide-progress location and its thickness. (author)

  20. 77 FR 50576 - Damage Tolerance and Fatigue Evaluation of Composite Rotorcraft Structures; OMB Approval of...

    Science.gov (United States)

    2012-08-22

    ... Composite Rotorcraft Structures; OMB Approval of Information Collection AGENCY: Federal Aviation... Rotorcraft Structures,'' which was published on December 1, 2011. DATES: The rule published on December 1... and Fatigue Evaluation of Composite Rotorcraft Structures,'' published in the Federal Register (76 FR...

  1. Damage evaluation under thermal fatigue of a vertical target full scale component for the ITER divertor

    International Nuclear Information System (INIS)

    Missirlian, M.; Escourbiac, F.; Merola, M.; Durocher, A.; Bobin-Vastra, I.; Schedler, B.

    2007-01-01

    An extensive development programme has been carried out in the EU on high heat flux components within the ITER project. In this framework, a Full Scale Vertical Target (VTFS) prototype was manufactured with all the main features of the corresponding ITER divertor design. The fatigue cycling campaign on CFC and W armoured regions, proved the capability of such a component to meet the ITER requirements in terms of heat flux performances for the vertical target. This paper discusses thermographic examination and thermal fatigue testing results obtained on this component. The study includes thermal analysis, with a tentative proposal to evaluate with finite element approach the location/size of defects and the possible propagation during fatigue cycling

  2. High frequency fatigue test of IN 718 alloy – microstructure and fractography evaluation

    Directory of Open Access Journals (Sweden)

    J. Belan

    2015-01-01

    Full Text Available INCONEL alloy 718 is a high-strength, corrosion-resistant nickel chromium material used at -253 °C to 705 °C for production of heat resistant parts of aero jet engine mostly. The fatigue test provided on this kind materials were done via low frequency loading up to this time. Nowadays, needs of results at higher volume of loading cycles leads to high frequency loading with aim to shorten testing time. Fatigue test of experimental material was carried out at frequency 20 kHz with stress ration R = - 1 (push – pull at room temperature. It was found that this superalloy can still fracture after exceeding 108 cycles. Besides fatigue test were microstructural characterisation and scanning electron microscopy (SEM fractography evaluation done.

  3. Evaluation of fatigue cracks in FSW joints of industrial structural materials by laminography

    International Nuclear Information System (INIS)

    Sano, Yuji; Masaki, Kiyotaka; Kajiwara, Kentaro

    2016-01-01

    Friction stir welding (FSW) is an emerging technology for joining flat and thin metal materials and has been applied in manufacturing in aviation and automotive industries. Fatigue property is one of the most important items to be evaluated for the structural integrity of the products, and therefore, it is necessary to visualize the three-dimensional (3D) behavior of fatigue cracks propagating in the non-homogeneous and anisotropic stirred zone of FSW joints. We have applied laminography with synchrotron radiation of SPring-8 to the FSW joints of aluminum alloy as a typical structural material. The results showed that the fatigue cracks propagated in a unique way depending on the stirred material. (author)

  4. Creep-fatigue evaluation method for modified 9Cr-1Mo steel

    International Nuclear Information System (INIS)

    Wada, Y.; Aoto, K.

    1997-01-01

    As creep-fatigue evaluation methods on normalized and tempered Modified 9Cr-1Mo steel for design use, the time fraction rule and the simplified conventional ductility exhaustion rule are investigated for the prediction of tension strain hold creep-fatigue damage of this material. For the above investigation, stress relaxation behaviour during strain hold has to be analyzed using stress-strain-time relation. The initial value of stress relaxation was determined by cyclic stress-strain curves in continuous cycling fatigue tests. Cyclic stress-strain behaviour of Mod.9Cr-1Mo(NT) steel is different from that of austenitic stainless steels, so this effect was considered. Stress relaxation analysis was performed using static creep strain-time relation and conventional hardening rule. The time fraction by using the above stress relaxation analysis results can give good prediction for creep-fatigue life of Mod.9Cr-1Mo(NT) steel. For design use it is practical to be able to estimate creep damages conservatively by both strain behaviour of cyclic plastic (in continuous cycling fatigue tests) and monotonic creep (in standard creep tests). The life reduction by strain hold at the minimum peak of compressive stress in creep-fatigue tests was examined, and this effects can be evaluated by the relationship between the location of oxidation and the effective deformation at crack tip. In an accelerated oxidation environment, for example in high temperature and high pressure steam, a different approach for life reduction should be developed based on the mechanism of growth of oxide and crack growth with oxidation. However, in the creep damage dominant region, its effect is saturated and the effect of cavity growth along grain boundary becomes dominant for long-term strain hold in the high temperature conditions. (author). 6 refs, 6 figs

  5. Methodology of investment effectiveness evaluation in the local energy market

    Energy Technology Data Exchange (ETDEWEB)

    Kamrat, W.

    1999-07-01

    The paper presents issues of investment effectiveness evaluation in the local energy market. Results of research presented in the paper are mainly proposing a concept of a methodology which allows the evaluation of investment processes in regional power markets at the decision-making stage. In this respect, selecting a rational investment strategy is an important stage of the entire investment process. In view of criteria of various nature, the construction of a methodology of investment effectiveness bears an especially important meaning for a local decision-maker or investor. It is of particular significance to countries that are undergoing a transition from a centrally planned economy to a market economy. (orig.)

  6. Surface Irregularity Factor as a Parameter to Evaluate the Fatigue Damage State of CFRP

    Science.gov (United States)

    Zuluaga-Ramírez, Pablo; Frövel, Malte; Belenguer, Tomás; Salazar, Félix

    2015-01-01

    This work presents an optical non-contact technique to evaluate the fatigue damage state of CFRP structures measuring the irregularity factor of the surface. This factor includes information about surface topology and can be measured easily on field, by techniques such as optical perfilometers. The surface irregularity factor has been correlated with stiffness degradation, which is a well-accepted parameter for the evaluation of the fatigue damage state of composite materials. Constant amplitude fatigue loads (CAL) and realistic variable amplitude loads (VAL), representative of real in- flight conditions, have been applied to “dog bone” shaped tensile specimens. It has been shown that the measurement of the surface irregularity parameters can be applied to evaluate the damage state of a structure, and that it is independent of the type of fatigue load that has caused the damage. As a result, this measurement technique is applicable for a wide range of inspections of composite material structures, from pressurized tanks with constant amplitude loads, to variable amplitude loaded aeronautical structures such as wings and empennages, up to automotive and other industrial applications. PMID:28793655

  7. Surface Irregularity Factor as a Parameter to Evaluate the Fatigue Damage State of CFRP

    Directory of Open Access Journals (Sweden)

    Pablo Zuluaga-Ramírez

    2015-11-01

    Full Text Available This work presents an optical non-contact technique to evaluate the fatigue damage state of CFRP structures measuring the irregularity factor of the surface. This factor includes information about surface topology and can be measured easily on field, by techniques such as optical perfilometers. The surface irregularity factor has been correlated with stiffness degradation, which is a well-accepted parameter for the evaluation of the fatigue damage state of composite materials. Constant amplitude fatigue loads (CAL and realistic variable amplitude loads (VAL, representative of real in- flight conditions, have been applied to “dog bone” shaped tensile specimens. It has been shown that the measurement of the surface irregularity parameters can be applied to evaluate the damage state of a structure, and that it is independent of the type of fatigue load that has caused the damage. As a result, this measurement technique is applicable for a wide range of inspections of composite material structures, from pressurized tanks with constant amplitude loads, to variable amplitude loaded aeronautical structures such as wings and empennages, up to automotive and other industrial applications.

  8. Observations and recommendations for further research regarding environmentally assisted fatigue evaluation methods

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, G.L.; Tregoning, R.L. [U.S. Nuclear Regulatory Commission (U.S. NRC), Rockville, MD (United States); Chopra, O.K. [Argonne National Laboratory, Argonne, IL (United States)

    2014-07-01

    The U.S. Nuclear Regulatory Commission (NRC) and Argonne National Laboratory (ANL) have completed research activities on environmentally assisted fatigue (EAF) methods. This work has led to a revision of NUREG/CR-6909 in its entirety, a draft of which is forthcoming for public review and comment. These activities addressed the following areas: - Air and water fatigue curves were re-developed using a much larger fatigue (ε-N) database. The additional data include an expansion in the ε-N data previously used by the NRC and ANL by as much as 50%. - The environmental fatigue multiplier (F{sub en}) expressions for carbon, low-alloy, stainless, and nickel-alloy steels were revised. - The revised F{sub en} expressions address comments from interested stakeholders related to: (a) the constants in previous F{sub en} expressions that results in F{sub en} values of approximately 2.0 even when the strain rate is very high or the temperature is very low, (b) the temperature dependence of the F{sub en} expression for carbon and low-alloy steels, and (c) the dependence of F{sub en} on water chemistry for austenitic stainless steels. - In addition, the appropriateness of a strain threshold and the possible effects of hold periods were evaluated. - The potential effects of dynamic strain aging (DSA) on cyclic deformation and environmental effects were discussed. - The revised F{sub en} expressions proposed were validated to the extent possible by comparing the results of five different experimental data sets obtained from fatigue tests that simulate actual plant conditions to estimates of fatigue usage adjusted for environmental effects using the updated F{sub en} expressions. In the course of performing the foregoing EAF research activities, the NRC and ANL observed several areas where further research could yield reduced conservatism in EAF evaluation. These include more refined, material-specific fatigue (S-N) curves, S-N curves for ferritic materials based on material tensile

  9. Evaluation Methodology. The Evaluation Exchange. Volume 11, Number 2, Summer 2005

    Science.gov (United States)

    Coffman, Julia, Ed.

    2005-01-01

    This is the third issue of "The Evaluation Exchange" devoted entirely to the theme of methodology, though every issue tries to identify new methodological choices, the instructive ways in which people have applied or combined different methods, and emerging methodological trends. For example, lately "theories of change" have gained almost…

  10. Safety analysis and evaluation methodology for fusion systems

    International Nuclear Information System (INIS)

    Fujii-e, Y.; Kozawa, Y.; Namba, C.

    1987-03-01

    Fusion systems which are under development as future energy systems have reached a stage that the break even is expected to be realized in the near future. It is desirable to demonstrate that fusion systems are well acceptable to the societal environment. There are three crucial viewpoints to measure the acceptability, that is, technological feasibility, economy and safety. These three points have close interrelation. The safety problem is more important since three large scale tokamaks, JET, TFTR and JT-60, start experiment, and tritium will be introduced into some of them as the fusion fuel. It is desirable to establish a methodology to resolve the safety-related issues in harmony with the technological evolution. The promising fusion system toward reactors is not yet settled. This study has the objective to develop and adequate methodology which promotes the safety design of general fusion systems and to present a basis for proposing the R and D themes and establishing the data base. A framework of the methodology, the understanding and modeling of fusion systems, the principle of ensuring safety, the safety analysis based on the function and the application of the methodology are discussed. As the result of this study, the methodology for the safety analysis and evaluation of fusion systems was developed. New idea and approach were presented in the course of the methodology development. (Kako, I.)

  11. Methodology for evaluating gloves in relation to the effects on hand performance capabilities: a literature review.

    Science.gov (United States)

    Dianat, Iman; Haslegrave, Christine M; Stedmon, Alex W

    2012-01-01

    The present study was conducted to review the literature on the methods that have been considered appropriate for evaluation of the effects of gloves on different aspects of hand performance, to make recommendations for the testing and assessment of gloves, and to identify where further research is needed to improve the evaluation protocols. Eighty-five papers meeting the criteria for inclusion were reviewed. Many studies show that gloves may have negative effects on manual dexterity, tactile sensitivity, handgrip strength, muscle activity and fatigue and comfort, while further research is needed to determine glove effects on pinch strength, forearm torque strength and range of finger and wrist movements. The review also highlights several methodological issues (including consideration of both task type and duration of glove use by workers, guidance on the selection and allocation of suitable glove(s) for particular tasks/jobs, and glove design features) that need to be considered in future research. Practitioner Summary: The relevant literature on the effects of protective gloves on different aspects of hand performance was reviewed to make recommendations for the testing and assessment of gloves, and to improve evaluation protocols. The review highlights research areas and methodological issues that need to be considered in future research.

  12. Operating data monitoring and fatigue evaluation systems and findings for boiling water reactors in Japan

    International Nuclear Information System (INIS)

    Maekawa, O.; Kanazawa, Y.; Takahashi, Y.; Tani, M.

    1995-01-01

    The reactor pressure vessel (RPV) is one of the most critical components of a boiling water reactor (BWR) when utilities think about plant life extension (PLEX). Design stress analysis sometimes reports very high fatigue usage factors for such portions of RPVs as stud bolt, feedwater nozzle and support skirt.In order to evaluate design margin and to eliminate excessive conservatism in this design analysis to pave the way for PLEX, Japanese BWR utilities jointly with BWR manufacturers in Japan established a programme (1) to acquire plant operational data on line for specific parameters used in stress analysis, (2) to evaluate margin in the design using measured plant data best estimate boundary conditions for stress analysis, and (3) to establish a simplified fatigue analysis method for BWR RPV.A plant data acquisition system, named OPEDAS, has been developed and installed in Tokyo Electric Power Company's 1100MWe BWR at its Kashiwazaki-Kariwa nuclear power plant. Best estimate stress analysis using measured in-plant data has been carried out and the results show considerable margin in fatigue usage factor over the design. A simplified fatigue analysis method using in-plant data has been developed with the Green's function, although some limitations have been identified for its use. ((orig.))

  13. A Theoretical and Methodological Evaluation of Leadership Research.

    Science.gov (United States)

    Lashbrook, Velma J.; Lashbrook, William B.

    This paper isolates some of the strengths and weaknesses of leadership research by evaluating it from both a theoretical and methodological perspective. The seven theories or approaches examined are: great man, trait, situational, style, functional, social influence, and interaction positions. General theoretical, conceptual, and measurement…

  14. Guidelines for reporting evaluations based on observational methodology.

    Science.gov (United States)

    Portell, Mariona; Anguera, M Teresa; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana

    2015-01-01

    Observational methodology is one of the most suitable research designs for evaluating fidelity of implementation, especially in complex interventions. However, the conduct and reporting of observational studies is hampered by the absence of specific guidelines, such as those that exist for other evaluation designs. This lack of specific guidance poses a threat to the quality and transparency of these studies and also constitutes a considerable publication hurdle. The aim of this study thus was to draw up a set of proposed guidelines for reporting evaluations based on observational methodology. The guidelines were developed by triangulating three sources of information: observational studies performed in different fields by experts in observational methodology, reporting guidelines for general studies and studies with similar designs to observational studies, and proposals from experts in observational methodology at scientific meetings. We produced a list of guidelines grouped into three domains: intervention and expected outcomes, methods, and results. The result is a useful, carefully crafted set of simple guidelines for conducting and reporting observational studies in the field of program evaluation.

  15. A multiple feedback methodology for the study of creativity evaluations

    DEFF Research Database (Denmark)

    Glaveanu, Vlad Petre

    2012-01-01

    The cultural psychology perspective emphasizes the role of communication and social interaction in the construction of representations and evaluations concerning creativity. In terms of creativity assessment, this approach leads to the use of a multiple feedback methodology selecting several groups...... useful for investigating the social and cultural dynamics of creativity....

  16. Evaluation and testing methodology for evolving entertainment systems

    NARCIS (Netherlands)

    Jurgelionis, A.; Bellotti, F.; IJsselsteijn, W.A.; Kort, de Y.A.W.; Bernhaupt, R.; Tscheligi, M.

    2007-01-01

    This paper presents a testing and evaluation methodology for evolving pervasive gaming and multimedia systems. We introduce the Games@Large system, a complex gaming and multimedia architecture comprised of a multitude of elements: heterogeneous end user devices, wireless and wired network

  17. Evaluation of methodologies for remunerating wind power's reliability in Colombia

    International Nuclear Information System (INIS)

    Botero B, Sergio; Isaza C, Felipe; Valencia, Adriana

    2010-01-01

    Colombia strives to have enough firm capacity available to meet unexpected power shortages and peak demand; this is clear from mechanisms currently in place that provide monetary incentives (in the order of nearly US$ 14/MW h) to power producers that can guarantee electricity provision during scarcity periods. Yet, wind power in Colombia is not able to currently guarantee firm power because an accepted methodology to calculate its potential firm capacity does not exist. In this paper we argue that developing such methodology would provide an incentive to potential investors to enter into this low carbon technology. This paper analyzes three methodologies currently used in energy markets around the world to calculate firm wind energy capacity: PJM, NYISO, and Spain. These methodologies are initially selected due to their ability to accommodate to the Colombian energy regulations. The objective of this work is to determine which of these methodologies makes most sense from an investor's perspective, to ultimately shed light into developing a methodology to be used in Colombia. To this end, the authors developed a methodology consisting on the elaboration of a wind model using the Monte-Carlo simulation, based on known wind behaviour statistics of a region with adequate wind potential in Colombia. The simulation gives back random generation data, representing the resource's inherent variability and simulating the historical data required to evaluate the mentioned methodologies, thus achieving the technology's theoretical generation data. The document concludes that the evaluated methodologies are easy to implement and that these do not require historical data (important for Colombia, where there is almost no historical wind power data). It is also found that the Spanish methodology provides a higher Capacity Value (and therefore a higher return to investors). The financial assessment results show that it is crucial that these types of incentives exist to make viable

  18. Development of Testing Methodologies to Evaluate Postflight Locomotor Performance

    Science.gov (United States)

    Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Richards, J. T.; Miller, C. A.; Brady, R.; Warren, L. E.; Bloomberg, J. J.

    2006-01-01

    Crewmembers experience locomotor and postural instabilities during ambulation on Earth following their return from space flight. Gait training programs designed to facilitate recovery of locomotor function following a transition to a gravitational environment need to be accompanied by relevant assessment methodologies to evaluate their efficacy. The goal of this paper is to demonstrate the operational validity of two tests of locomotor function that were used to evaluate performance after long duration space flight missions on the International Space Station (ISS).

  19. Performance evaluation methodology for historical document image binarization.

    Science.gov (United States)

    Ntirogiannis, Konstantinos; Gatos, Basilis; Pratikakis, Ioannis

    2013-02-01

    Document image binarization is of great importance in the document image analysis and recognition pipeline since it affects further stages of the recognition process. The evaluation of a binarization method aids in studying its algorithmic behavior, as well as verifying its effectiveness, by providing qualitative and quantitative indication of its performance. This paper addresses a pixel-based binarization evaluation methodology for historical handwritten/machine-printed document images. In the proposed evaluation scheme, the recall and precision evaluation measures are properly modified using a weighting scheme that diminishes any potential evaluation bias. Additional performance metrics of the proposed evaluation scheme consist of the percentage rates of broken and missed text, false alarms, background noise, character enlargement, and merging. Several experiments conducted in comparison with other pixel-based evaluation measures demonstrate the validity of the proposed evaluation scheme.

  20. Status of Methodology Development for the Evaluation of Proliferation Resistance

    International Nuclear Information System (INIS)

    Lee, Yong Deok; Ko, Won Il; Lee, Jung Won

    2010-01-01

    Concerning the increasing energy demand and green house effect, nuclear energy is now the most feasible option. Therefore, recently, oil countries even have a plan to build the nuclear power plant for energy production. If nuclear systems are to make a major and sustainable contribution to the worlds energy supply, future nuclear energy systems must meet specific requirements. One of the requirements is to satisfy the proliferation resistance condition in an entire nuclear system. Therefore, from the beginning of future nuclear energy system development, it is important to consider a proliferation resistance to prevent the diversion of nuclear materials. The misuse of a nuclear system must be considered as well. Moreover, in the import and export of nuclear system, the evaluation of the proliferation resistance on the nuclear system becomes a key factor The INPRO (International Project on Innovative Nuclear Reactors and Fuel Cycles) program initiated by the IAEA proposed proliferation resistance (PR) as a key component of a future innovative nuclear system (INS) with a sustainability, economics, safety of nuclear installation and waste management. The technical goal for Generation IV (Gen IV) nuclear energy systems (NESs) highlights a Proliferation Resistance and Physical Protection (PR and PP), sustainability, safety, reliability and economics as well. Based on INPRO and Gen IV study, the methodology development for the evaluation of proliferation resistance has been carried out in KAERI. Finally, the systematic procedure for methodology was setup and the indicators for the procedure were decided. The methodology involves the evaluation from total nuclear system to individual process. Therefore, in this study, the detailed procedure for the evaluation of proliferation resistance and the newly proposed additional indicators are described and several conditions are proposed to increase the proliferation resistance in the future nuclear system. The assessment of PR

  1. Evaluation methodology for fixed-site physical protection systems

    International Nuclear Information System (INIS)

    Bennett, H.A.; Olascoaga, M.T.

    1980-01-01

    A system performance evaluation methodology has been developed to aid the Nuclear Regulatory Commission (NRC) in the implementation of new regulations designed to upgrade the physical protection of nuclear fuel cycle facilities. The evaluation methodology, called Safeguards Upgrade Rule Evaluation (SURE), provides a means of explicitly incorporating measures for highly important and often difficult to quantify performance factors, e.g., installation, maintenance, training and proficiency levels, compatibility of components in subsystems, etc. This is achieved by aggregating responses to component and system questionaires through successive levels of a functional hierarchy developed for each primary performance capability specified in the regulations, 10 CFR 73.45. An overall measure of performance for each capability is the result of this aggregation process. This paper provides a descripton of SURE

  2. Experimentally Validated Combustion and Piston Fatigue Life Evaluation Procedures for the Bi-Fuel Engines, Using an Integral-Type Fatigue Criterion

    Directory of Open Access Journals (Sweden)

    M. Shariyat

    Full Text Available Abstract A relatively complete procedure for high cycle fatigue life assessment of the engine components is outlined in the present paper. The piston is examined as a typical component of the engine. In this regard, combustion process and transient heat transfer simulations, determination of the instantaneous variations of the pressure and temperature in the combustion chamber, kinematic and dynamic analyses of the moving parts of the engine, thermoelastic stress analyses, and fatigue life analyses are accomplished. Results of the simulation are compared with the test data to verify the results. The heat transfer results are validated by the experimental results measured by the Templugs. The nonlinear multipoint contact constraints are modeled accurately. Results of the more accurate available fatigue criteria are compared with those of a fatigue criterion recently proposed by the first author. These results are also evaluated by comparing them with the experimental durability tests. The presented procedure may be used, e.g., to decide whether it is suitable to convert a gasoline-based engine to a bi-fuel one. Results of the various thermomechanical fatigue analyses performed reveal that the piston life decreases considerably when natural gas is used instead of gasoline.

  3. Methodology For Evaluation Of Regulatory Effectiveness In Physical Protection

    International Nuclear Information System (INIS)

    Izmaylov, Alexander; Valente, John; Griggs, James R.; Rexroth, Paul; Piskarev, Alexander; Babkin, Vladimir; Sokolov, Egor; Melton, Ronald B.; Cunningham, Mitchel E.; Baker, Kathryn A.; Brothers, Alan J.

    2005-01-01

    Material protection, control, and accounting (MPC and A) regulatory documents play an important role in securing and protecting nuclear material by regulating a variety of activities at different hierarchical levels. The development, implementation, and practical application of these regulatory documents requires a significant investment of financial and material resources. Therefore, it is important to evaluate the effectiveness of the regulatory development process and the extent to which regulations improve the effectiveness of MPC and A at nuclear sites. The joint Russian and U.S. Regulatory Development Project has a goal of evaluating the effectiveness of regulatory documents developed for MPC and A. As part of this joint Project, a methodology for evaluating effectiveness has been developed. This methodology was developed around physical protection objectives. The developed methodology specifies physical protection objectives to be accomplished through the implementation of a regulatory system based on the physical protection goals at the nuclear sites. It includes approaches to assessing regulatory effectiveness, the hierarchical structure of physical protection objectives to be accomplished through implementing regulations, a 'mapping' of the physical protection objectives to the regulatory framework, a list of criteria for evaluating the effectiveness of physical protection regulations and effectiveness indicators, as well as means and methods for gathering information and implementation of this evaluation.

  4. A real time evaluation technique of fatigue damage in adhesively bonded composite metal joints

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Hyun; Kwon Oh Yang [Dept. of Mechanical Engineering, Inje Univesity, Kimhae (Korea, Republic of)

    1999-05-15

    One of the problems for practical use of fiber-reinforced composite material is performance degradation by fatigue damage in the joints. The study is to develope a nondestructive technique for real-time evaluation of adhesively bonded composite-metal joints. From the prior study we confirmed that the bonding strength can be estimated from the correlation between quality of bonded parts and AUP's. We obtained a curve showing the correlation between AUP's calculated from signals obtained from single-lap and double-lap joints and the degree of fatigue damage at bonding interface during fatigue test. The curve is an analogy to the one showing stiffness reduction(E/E{sub 0}) of polymer matrix composites by fatigue damage. From those facts, it is possible to predict degree of damage in real-time. Amplitude and AUP2 appeared to be optimal parameters to provide more reliable results for single-lap joint whereas amplitude and AUP1 did for double-lap joints. It is recommended to select optimal parameters for different geometries in the real structure.

  5. A real time evaluation technique of fatigue damage in adhesively bonded composite metal joints

    International Nuclear Information System (INIS)

    Kim, Tae Hyun; Kwon Oh Yang

    1999-01-01

    One of the problems for practical use of fiber-reinforced composite material is performance degradation by fatigue damage in the joints. The study is to develope a nondestructive technique for real-time evaluation of adhesively bonded composite-metal joints. From the prior study we confirmed that the bonding strength can be estimated from the correlation between quality of bonded parts and AUP's. We obtained a curve showing the correlation between AUP's calculated from signals obtained from single-lap and double-lap joints and the degree of fatigue damage at bonding interface during fatigue test. The curve is an analogy to the one showing stiffness reduction(E/E 0 ) of polymer matrix composites by fatigue damage. From those facts, it is possible to predict degree of damage in real-time. Amplitude and AUP2 appeared to be optimal parameters to provide more reliable results for single-lap joint whereas amplitude and AUP1 did for double-lap joints. It is recommended to select optimal parameters for different geometries in the real structure.

  6. Trunk muscle fatigue during a lateral isometric hold test: what are we evaluating?

    Directory of Open Access Journals (Sweden)

    Pagé Isabelle

    2012-04-01

    Full Text Available Abstract Background Side bridge endurance protocols have been suggested to evaluate lateral trunk flexor and/or spine stabilizer muscles. To date, no study has investigated muscle recruitment and fatigability during these protocols. Therefore the purpose of our study was to quantify fatigue parameters in various trunk muscles during a modified side bridge endurance task (i.e. a lateral isometric hold test on a 45° roman chair apparatus and determine which primary trunk muscles get fatigued during this task. It was hypothesized that the ipsilateral external oblique and lumbar erector spinae muscles will exhibit the highest fatigue indices. Methods Twenty-two healthy subjects participated in this study. The experimental session included left and right lateral isometric hold tasks preceded and followed by 3 maximal voluntary contractions in the same position. Surface electromyography (EMG recordings were obtained bilaterally from the external oblique, rectus abdominis, and L2 and L5 erector spinae. Statistical analysis were conducted to compare the right and left maximal voluntary contractions (MVC, surface EMG activities, right vs. left holding times and decay rate of the median frequency as the percent change from the initial value (NMFslope. Results No significant left and right lateral isometric hold tests differences were observed neither for holding times (97.2 ± 21.5 sec and 96.7 ± 24.9 sec respectively nor for pre and post fatigue root mean square during MVCs. However, participants showed significant decreases of MVCs between pre and post fatigue measurements for both the left and right lateral isometric hold tests. Statistical analysis showed that a significantly NMFslope of the ipsilateral external oblique during both conditions, and a NMFslope of the contralateral L5 erector spinae during the left lateral isometric hold test were steeper than those of the other side’s respective muscles. Although some participants

  7. Fatigue damage evaluation of stainless steel pipes in nuclear power plants using positron annihilation lineshape analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kawaguchi, Yasuhiro [Institute of Nuclear Safety System, Inc., Mihama, Fukui (Japan); Nakamura, Noriko; Yusa, Satoru [Ishikawajima-Harima Heavy Industries Co., Tokyo (Japan)

    2002-09-01

    Since positron annihilation lineshape analysis can evaluate the degree of fatigue damage by detecting defects such as dislocations in metals, we applied this method to evaluate that in a type 316 stainless steel pipe which was used in the primary system of a nuclear power plant. Using {sup 68}Ge as a positron source, an energy spread of annihilation gamma ray peak from the material was measured and expressed as the S-parameter. Actual plant material cut from a surge line pipe of a pressurizer in a pressurized water reactor type nuclear power plant was measured by positron annihilation lineshape analysis and the S-parameter was obtained. Comparing the S-parameter with a relationship between the S-parameter and fatigue life ratio of the type 316 stainless steel, we evaluated the degree of fatigue damage of the actual material. Furthermore, to verify the evaluation, microstructures of the actual material were investigated with TEM (transmission electron microscope) to observe dislocation densities. As a result, a change in the S-parameter of the actual material from standard as-received material (type 316 stainless steel) was in the range from -0.0013 to 0.0014, while variations in the S-parameter of the standard as-received material were about {+-}0.002, and hence the differences between the actual material and the as-received material were negligible. Moreover, the dislocation density of the actual plant material observed with TEM was almost the same as that of the as-received one. In conclusion, we could confirm the applicability of the positron annihilation lineshape analysis to fatigue damage evaluation of stainless steel. (author)

  8. Evaluation of vibration and vibration fatigue life for small bore pipe in nuclear power plants

    International Nuclear Information System (INIS)

    Wang Zhaoxi; Xue Fei; Gong Mingxiang; Ti Wenxin; Lin Lei; Liu Peng

    2011-01-01

    The assessment method of the steady state vibration and vibration fatigue life of the small bore pipe in the supporting system of the nuclear power plants is proposed according to the ASME-OM3 and EDF evaluation methods. The GGR supporting pipe system vibration is evaluated with this method. The evaluation process includes the filtration of inborn sensitivity, visual inspection, vibration tests, allowable vibration effective velocity calculation and vibration stress calculation. With the allowable vibration effective velocity calculated and the vibration velocity calculated according to the acceleration data tested, the filtrations are performed. The vibration stress at the welding coat is calculated with the spectrum method and compared with the allowable value. The response of the stress is calculated with the transient dynamic method, with which the fatigue life is evaluated with the Miners linear accumulation model. The vibration stress calculated with the spectrum method exceeds the allowable value, while the fatigue life calculated from the transient dynamic method is larger than the designed life with a big safety margin. (authors)

  9. A new methodology for repository site suitability evaluation

    International Nuclear Information System (INIS)

    Miller, I.; Kossik, R.; Cunnane, M.

    1992-01-01

    Golder Associates Inc. (GAI) has developed a probabilistic total system performance assessment and strategy evaluation model (RIP) which can be applied in an iterative manner to evaluate repository site suitability and guide site characterization. The major portion of the software is the performance assessment model, which consists of a series of coupled component models for radionuclide transfer. The performance model itself is embedded within a decision analysis model which allows the user to evaluate alternative site characterization strategies. This paper provides an overview of the methodology, and summarizes the basic concepts of RIP

  10. Evaluation of the strain rate effects on environmental fatigue life of CF8M cast stainless steel

    International Nuclear Information System (INIS)

    Jeong, Ill Seok; Ha, Gak Hyun; Jeon, Hyun Ik

    2009-01-01

    The environmental fatigue life of CF8M cast stainless steel is influenced by mechanical, environmental and metallurgical parameters, such as strain rate, strain amplitude, temperature, dissolved oxygen concentration, water flow rate and so on. In an actual plant, the mechanical and environmental parameters are changing during the plant operation. Therefore, the effect of such mechanical and environmental parameter changes on fatigue life evaluation have to be studied. Low cycle fatigue life of structural materials diminishes remarkably as functions of various parameters in high temperature and high pressure environments. Such reduction can be estimated by the fatigue life reduction factor(F en ). In this study, fatigue tests were performed under changing conditions of strain amplitude, strain rate. Fatigue life was measured in terms of the number of cycles with the variation of strain amplitudes at 0.004 %/s strain rate, and the fatigue life correction factor was evaluated according to the equation modified by U. S. Nuclear Regulatory Commission(U.S.NRC) and Japanese Environmental Fatigue Tests committee (JEFT).

  11. Evaluation of work posture and quantification of fatigue by Rapid Entire Body Assessment (REBA)

    Science.gov (United States)

    Rizkya, I.; Syahputri, K.; Sari, R. M.; Anizar; Siregar, I.

    2018-02-01

    Work related musculoskeletal disorders (MSDs), poor body postures, and low back injuries are the most common problems occurring in many industries including small-medium industries. This study presents assessment and evaluation of ergonomic postures of material handling worker. That evaluation was carried out using REBA (Rapid Entire Body Assessment). REBA is a technique to quantize the fatigue experienced by the worker while manually lifting loads. Fatigue due to abnormal work posture leads to complaints of labor-perceived pain. REBA methods were used to an assessment of working postures for the existing process by a procedural analysis of body postures involved. This study shows that parts of the body have a high risk of work are the back, neck, and upper arms with REBA score 9, so action should be taken as soon as possible. Controlling actions were implemented to those process with high risk then substantial risk reduction was achieved.

  12. 76 FR 75435 - Fatigue Tolerance Evaluation of Metallic Structures

    Science.gov (United States)

    2011-12-02

    ... applicant to evaluate the strength of various rotorcraft components including--but not limited to--rotors, rotor drive systems between the engines and the main and tail rotor hubs, controls, fuselage, fixed and... operation. About that same time, rotorcraft manufacturers were introducing advanced composite materials for...

  13. Fracture mechanics and fatigue evaluation of nuclear reactor components

    International Nuclear Information System (INIS)

    Mattar Neto, Miguel; Andrade, Arnaldo H.P. de; Maneschy, Eduardo

    1995-01-01

    This paper presents a theoretical study available in the available literature for evaluation the environmental effects on the lifetime of nuclear power plant components. The author's motivation is to provide some technical tools to identify what research development could be done in this area

  14. A pilot study evaluating the safety and efficacy of modafinal for cancer-related fatigue.

    Science.gov (United States)

    Blackhall, Leslie; Petroni, Gina; Shu, Jianfen; Baum, Lora; Farace, Elena

    2009-05-01

    Fatigue is a common symptom that lowers the quality of life of patients with cancer, affecting between 60% and 90% of patients. Relatively few options are available for the treatment of this debilitating condition. Modafinal, a psychostimulant developed for the treatment of narcolepsy, has been used to treat fatigue in other diseases such as multiple sclerosis, but little data support its use in cancer patients. The primary objective of this open-label pilot study was to evaluate the safety, and efficacy of modafinil in improving cancer-related fatigue (CRF) as measured by the Brief Fatigue Inventory (BFI). The effect of this agent on depression, quality of life, functional status, and cognitive function was also assessed. Modafinal was self-administered at a dose of 100 mg/d during weeks 1-2, and 200 mg during weeks 3-4. Assessments were performed at baseline, 2, and 4 weeks. BFI score was improved in 46% of patients at 2 weeks and 75% at 4 weeks (p = 0.025). Hospital Anxiety and Depression Scale scores declined at 2 and 4 weeks (p < 0.001). Most scales for neurocognitive function were unchanged. Score for all Functional Assessment of Cancer Therapy-Brain (FACT-BR) subscales (measuring quality of life), except social/family well-being, were improved (p < 0.05) at 2 and 4 weeks. Significant changes in Eastern Cooperative Oncology Group (ECOG) performance status were noted, with 40% of patients improving at least one level. Modafinil was well-tolerated with only one patient discontinuing treatment due to drug-related toxicity. In this pilot study modafinil was well-tolerated and effective for fatigue in patients with cancer. Improvements were also seen in mood, quality of life, and functional status.

  15. Ratchetting and creep-fatigue evaluation for nozzle-to-cylinder intersection

    International Nuclear Information System (INIS)

    Barsoum, R.S.; Loomis, R.W.; Stewart, B.D.

    1976-01-01

    The study is part of an analytical investigation on the applicability of the simplified ratchetting and creep-fatigue rules to LMFBR component geometry. Both the detailed inelastic rules and the simplified elastic rules are applied to the results obtained from a three-dimensional finite element analysis of the nozzle-to-cylinder intersection. The results of both evaluations are compared at several locations on the surface, and an assessment of the degree of conservatism of the simplified methods is discussed

  16. Thermal fatigue and creep evaluation for the bed in tritium SDS

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Woo-seok, E-mail: wschoi@kaeri.re.kr [Korea Atomic Energy Research Institute, Yuseong, Daejeon (Korea, Republic of); Park, Chang-gyu [Korea Atomic Energy Research Institute, Yuseong, Daejeon (Korea, Republic of); Ju, Yong-sun [KOASIS, Yuseong, Daejeon (Korea, Republic of); Kang, Hyun-goo; Jang, Min-ho; Yun, Sei-hun [National Fusion Research Institute, Yuseong, Daejeon (Korea, Republic of)

    2016-11-01

    Highlights: • To evaluate the integrity of the ITER tritium SDS bed, three kinds of assessments were conducted. • The structural analysis showed that the stress induced from the thermal load and the internal pressure is within the design stress intensity. • The combined fatigue and creep assessment was also performed according to the procedure of ASME code Subsection NH. • A new operation procedure to obtain more integrity margin was recommended. • The other operation procedure could be considered which makes the rapid operation possible giving up the marginal integrity. - Abstract: The primary vessel of ITER tritium SDS bed is made of stainless steel. It is heated beyond 500 °C to desorb tritium. During this process the primary vessel is subject to thermal stress. And it is also subject to thermal fatigue by the iterative process of absorption and desorption. In addition, its operation temperature range is in the thermal creep temperature region. Therefore, the tritium SDS bed should have sufficient design stress intensity under the high temperature operating conditions. It should also be free of damage due to fatigue during the design life. Thermal analysis and structural analysis was performed using a finite element method to calculate the temperature and the stress distribution of the ITER tritium SDS bed due to the internal pressure and thermal loads. The thermal fatigue and creep effects were also evaluated since the tritium SDS bed was heated to hot temperature region where creep occurs. Based on the distribution of the primary stress and secondary stress results, two evaluation cross-sections were selected. The evaluation showed that the calculated value on the cross-sections satisfied all of the limits of the design code requirements.

  17. A progressive methodology for seismic safety evaluation of gravity dams

    International Nuclear Information System (INIS)

    Ghrib, F.; Leger, P.; Tinawi, R.; Lupien, R.; Veilleux, M.

    1995-01-01

    A progressive methodology for the seismic safety evaluation of existing concrete gravity dams was described. The methodology was based on five structural analysis levels with increasing complexity to represent inertia forces, dam-foundation and dam-interaction mechanisms, as well as concrete cracking. The five levels were (1) preliminary screening, (2) pseudo-static method, (3) pseudo-dynamic method, (4) linear time history analysis, and (5) non-linear history analysis. The first four levels of analysis were applied for the seismic safety evaluation of Paugan gravity dam (Quebec). Results showed that internal forces from pseudo-dynamic, response spectra and transient finite element analyses could be used to interpret the dynamic stability of dams from familiar strength-based criteria. However, as soon as the base was cracked, the seismically induced forces were modified, and level IV analyses proved more suitable to handle rationally these complexities. 8 refs., 7 figs., 1 tab

  18. Development of a comprehensive management site evaluation methodology

    International Nuclear Information System (INIS)

    Rodgers, J.C.; Onishi, Y.

    1981-01-01

    The Nuclear Regulatory Commission is in the process of preparing regulations that will define the necessary conditions for adequate disposal of low-level waste (LLW) by confinement in an LLW disposal facility. These proposed regulations form the context in which the motivation for the joint Los Alamos National Laboratory Battelle Pacific Northwest Laboratory program to develop a site-specific, LLW site evaluation methodology is discussed. The overall effort is divided into three development areas: land-use evaluation, environmental transport modelling, and long term scenario development including long-range climatology projections. At the present time four steps are envisioned in the application of the methodology to a site: site land use suitability assessment, land use-ecosystem interaction, contaminant transport simulation, and sensitivity analysis. Each of these steps is discussed in the paper. 12 refs

  19. METHODOLOGICAL PRINCIPLES AND METHODS OF TERMS OF TRADE STATISTICAL EVALUATION

    Directory of Open Access Journals (Sweden)

    N. Kovtun

    2014-09-01

    Full Text Available The paper studies the methodological principles and guidance of the statistical evaluation of terms of trade for the United Nations classification model – Harmonized Commodity Description and Coding System (HS. The practical implementation of the proposed three-stage model of index analysis and estimation of terms of trade for Ukraine's commodity-members for the period of 2011-2012 are realized.

  20. Primary study on quantitative evaluation of driver fatigue; Unten hiro no teiryo hyoka gijutsu ni kansuru kiso kento

    Energy Technology Data Exchange (ETDEWEB)

    Noguchi, Y; Mochizuki, M; Toyofuku, K [Isuzu Advanced Engineering Center, Ltd., Tokyo (Japan); Katsuura, T [Chiba University, Chiba (Japan)

    1997-10-01

    Quantitative evaluation of physical and mental loads are effective in developing more human-friendly vehicles. Here attention has been focused on the mental load. Attempts were made to find some physiological indices that can be used for quantifying the mental load and resultant fatigue. Subjects were told to perform three different tasks in a climatoron, and the relation between physiological indices and their perception of fatigue as well as their capability of performing the tasks were analyzed. As a result, heart rate variability is a good index for quantitative evaluation of mental load and fatigue. 5 refs., 4 figs., 6 tabs.

  1. Evaluation of analytical performance based on partial order methodology.

    Science.gov (United States)

    Carlsen, Lars; Bruggemann, Rainer; Kenessova, Olga; Erzhigitov, Erkin

    2015-01-01

    Classical measurements of performances are typically based on linear scales. However, in analytical chemistry a simple scale may be not sufficient to analyze the analytical performance appropriately. Here partial order methodology can be helpful. Within the context described here, partial order analysis can be seen as an ordinal analysis of data matrices, especially to simplify the relative comparisons of objects due to their data profile (the ordered set of values an object have). Hence, partial order methodology offers a unique possibility to evaluate analytical performance. In the present data as, e.g., provided by the laboratories through interlaboratory comparisons or proficiency testings is used as an illustrative example. However, the presented scheme is likewise applicable for comparison of analytical methods or simply as a tool for optimization of an analytical method. The methodology can be applied without presumptions or pretreatment of the analytical data provided in order to evaluate the analytical performance taking into account all indicators simultaneously and thus elucidating a "distance" from the true value. In the present illustrative example it is assumed that the laboratories analyze a given sample several times and subsequently report the mean value, the standard deviation and the skewness, which simultaneously are used for the evaluation of the analytical performance. The analyses lead to information concerning (1) a partial ordering of the laboratories, subsequently, (2) a "distance" to the Reference laboratory and (3) a classification due to the concept of "peculiar points". Copyright © 2014 Elsevier B.V. All rights reserved.

  2. INPRO Methodology to evaluate the Mexico nuclear energy system

    International Nuclear Information System (INIS)

    Cruz S, R. R.; Martin del C, C.

    2016-09-01

    The International Atomic Energy Agency has developed the so-called International Project on Fuel Cycles and Innovative Nuclear Reactors (INPRO), in order to make nuclear energy available to meet the energy needs of the 21 century, in a sustainable way. One of the tasks of the project is the evaluation of the nuclear systems, to check whether they meet the objectives of the project and whether they are sustainable. This paper explains the rationale and general characteristics of the project in the evaluation of nuclear energy systems based on the concept of sustainable development. It describes the methodology developed to carry out this evaluation, divided into seven areas, such as economic, environmental, security, etc., which together make up the sustainable development of energy through nuclear systems. The economic area is analyzed and the evaluation criteria and parameters established by INPRO are discussed, in order to evaluate the Mexican nuclear energy system using Nest (software developed within the same project) as a tool to support the economic evaluation of nuclear systems. Based on the energy strategy proposed by the Energy Secretary of the Mexican Government which seeks to reduce the greenhouse gas emissions from the national electricity generation park, two types of reactor of currently available technology (A BWR and AP1000), were compared and these in turn with other alternative energy generation technologies, such as combined cycle, geothermal and wind plants. Also, the results of the application of the INPRO methodology are presented. Finally, the recommendations on actions that could lead the Mexican nuclear energy system towards sustainable development and conclusions on the application of the methodology to the Mexican case are mentioned. (Author)

  3. Methodology to evaluate the insecticide potential of forest tree species

    International Nuclear Information System (INIS)

    Morales Soto, Leon; Garcia P, Carlos Mario

    2000-01-01

    The flora diversity of Colombia has an enormous potential in the rational use of its forest resources. Trees with biocidal effects to control pests and diseases need to be investigated. The objective of this research was to develop a methodology with low costs, easy application and quick results. The methodology employed was as follows: selection of tree species based on bibliography, ancestral reports and personal observations. The process was as follows: field collection of plants, preparation of plants extracts and test with Artemia salina Leach to detect biological activity of the extracts using LC50. Bioassays with those extract more promising (LC50 less than 1000 ppm) Determination of active compounds. The methodology was employed with 5 forest tree species: guarea guidonia (L) Sleumer and trichia hirta L. (Meliaceae), Machaerium Moritzianum Benth. (Fabaceae), Swinglea glutinosa Merrill (rutaceae) and Mammea americana L. (Clusiaceae). Using Artemia salina Leach as indicator of biocidal potential, two species were selected as the most promising, those were: Swinglea glutinosa Merril and Machaerium moritzianum Benth. In addition bioassays were made to evaluate fagoinhibition on Atta cephalotes (L.) (Hym: Formicidae) and control of Alconeura. This methodology is recommended for this kind of research

  4. Methodology for the insecticide potential evaluation of forest species

    International Nuclear Information System (INIS)

    Morales Soto, Leon; Garcia P, Carlos Mario

    2000-01-01

    The flora diversity of Colombia has an enormous potential in the rational use of its forest resources. Trees with biocides effects to pest control and diseases need to be investigated. The objective of this research was to develop a methodology with low costs, easy application and quick results. The methodology employed was as follows: selection of tree species based on bibliography, ancestral reports and personal observations. The process was as follows: field collection of plants, preparation of plants extracts, and test with Artemia Salina, leach to detect biological activity of the extracts using LC50. Bioassays with those extract more promising (LC50 less than 1000 ppm). The methodology was employed with 5 forest tree species: Guarea guidonia (L.) Sleumer and Trichia hirta L. (Meliaceae), machaerium moritzianum Benth. (Fabaceae), Swinglea glutinosa Merrill. (Rutaceae) and Mammea americana L. (Clusiaceae). Using Artemia salina Leach as indicator of biocidal potential, two species were selected as the most promising, those were: Swinglea glutinosa Merril and Machaerium moritzianum Benth. In addition bioassays were made to evaluate fagoinhibition on Atta cephalotes (L.) and control of Alconeura. This methodology is recommended for this kind of research

  5. Evaluation of Surface Fatigue Strength Based on Surface Temperature

    Science.gov (United States)

    Deng, Gang; Nakanishi, Tsutomu

    Surface temperature is considered to be an integrated index that is dependent on not only the load and the dimensions at the contact point but also the sliding velocity, rolling velocity, surface roughness, and lubrication conditions. Therefore, the surface durability of rollers and gears can be evaluated more exactly and simply by the use of surface temperature rather than Hertzian stress. In this research, surface temperatures of rollers under different rolling and sliding conditions are measured using a thermocouple. The effects of load P, mean velocity Vm and sliding velocity Vs on surface temperature are clarified. An experimental formula, which expresses the linear relationship between surface temperature and the P0.86Vs1.31Vm-0.83 value, is used to determine surface temperature. By comparing calculated and measured temperature on the tooth surface of a gear, this formula is confirmed to be applicable for gear tooth surface temperature calculation.

  6. Development of fatigue resistance evaluation method for socket-weld-jointed pipes

    International Nuclear Information System (INIS)

    Noguchi, Shinji; Shibayama, Motoaki; Iwata, Masazumi; Matsuura, Masayuki

    2003-01-01

    Vent line, drain line and sampling line in nuclear power station have many socket welded-joints made of austenitic stainless steel. Their slenderness and stagnation yield some potential of vibration-induced cracking and stress corrosion cracking. For the joints under vibration, the authors firstly elucidated their welding-defect-related fatigue strength by using fracture mechanics. It could define the allowable sets of stress amplitude and defect size. Secondly, authors developed an ultra-sonic detecting apparatus by using a focus-type probe and its programmed crawl on socket part. The authors finally measured the stress amplitude and frequency by sticking strain gage on suspected joints, then evaluated the fatigue resistance of the joints. For more efficient procedure, the method of stress amplitude analysis through vibration measurement is being developed. (author)

  7. Evaluation of fatigue damage for wind turbine blades using acoustic emission

    Energy Technology Data Exchange (ETDEWEB)

    Jee, Hyun Sup; Ju, No Hoe [Korea Institute of Materials Science, Changwon (Korea, Republic of); So, Cheal Ho [Dongshin University, Naju (Korea, Republic of); Lee, Jong Kyu [Dept. of Physics, Pukyung National University, Busan (Korea, Republic of)

    2015-06-15

    In this study, the flap fatigue test of a 48 m long wind turbine blade was performed for 1 million cycles to evaluate the characteristics of acoustic emission signals generated from fatigue damage of the wind blades. As the number of hits and total energy continued to increase during the first 0.6 million cycles, blade damage was constant. The rise-time result showed that the major aspects of damage were initiation and propagation of matrix cracks. In addition, the signal analysis of each channel showed that the most seriously damaged sections were the joint between the skin and spar, 20 m from the connection, and the spot of actual damage was observable by visual inspection. It turned out that the event source location was related to the change in each channel{sup s} total energy. It is expected that these findings will be useful for the optimal design of wind turbine blades.

  8. Report on an Assessment of the Application of EPP Results from the Strain Limit Evaluation Procedure to the Prediction of Cyclic Life Based on the SMT Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Jetter, R. I. [R. I. Jetter Consulting, Pebble Beach, CA (United States); Messner, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Sham, T. -L. [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Y. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    The goal of the proposed integrated Elastic Perfectly-Plastic (EPP) and Simplified Model Test (SMT) methodology is to incorporate an SMT data based approach for creep-fatigue damage evaluation into the EPP methodology to avoid the separate evaluation of creep and fatigue damage and eliminate the requirement for stress classification in current methods; thus greatly simplifying evaluation of elevated temperature cyclic service. This methodology should minimize over-conservatism while properly accounting for localized defects and stress risers. To support the implementation of the proposed methodology and to verify the applicability of the code rules, analytical studies and evaluation of thermomechanical test results continued in FY17. This report presents the results of those studies. An EPP strain limits methodology assessment was based on recent two-bar thermal ratcheting test results on 316H stainless steel in the temperature range of 405 to 7050C. Strain range predictions from the EPP evaluation of the two-bar tests were also evaluated and compared with the experimental results. The role of sustained primary loading on cyclic life was assessed using the results of pressurized SMT data from tests on Alloy 617 at 9500C. A viscoplastic material model was used in an analytic simulation of two-bar tests to compare with EPP strain limits assessments using isochronous stress strain curves that are consistent with the viscoplastic material model. A finite element model of a prior 304H stainless steel Oak Ridge National Laboratory (ORNL) nozzle-to-sphere test was developed and used for an EPP strain limits and creep-fatigue code case damage evaluations. A theoretical treatment of a recurring issue with convergence criteria for plastic shakedown illustrated the role of computer machine precision in EPP calculations.

  9. Model evaluation methodology applicable to environmental assessment models

    International Nuclear Information System (INIS)

    Shaeffer, D.L.

    1979-08-01

    A model evaluation methodology is presented to provide a systematic framework within which the adequacy of environmental assessment models might be examined. The necessity for such a tool is motivated by the widespread use of models for predicting the environmental consequences of various human activities and by the reliance on these model predictions for deciding whether a particular activity requires the deployment of costly control measures. Consequently, the uncertainty associated with prediction must be established for the use of such models. The methodology presented here consists of six major tasks: model examination, algorithm examination, data evaluation, sensitivity analyses, validation studies, and code comparison. This methodology is presented in the form of a flowchart to show the logical interrelatedness of the various tasks. Emphasis has been placed on identifying those parameters which are most important in determining the predictive outputs of a model. Importance has been attached to the process of collecting quality data. A method has been developed for analyzing multiplicative chain models when the input parameters are statistically independent and lognormally distributed. Latin hypercube sampling has been offered as a promising candidate for doing sensitivity analyses. Several different ways of viewing the validity of a model have been presented. Criteria are presented for selecting models for environmental assessment purposes

  10. Study on GIF PR/PP evaluation methodology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B. H.; Kwon, E. H.; Kim, H. D. [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    Proliferation resistance (PR) and physical protection (PP) is one of the four technology goals of generation IV nuclear energy systems (NESs). The PR component of the goal focuses on providing strong assurance that generation IV NESs are the least desirable sources for the diversion or undeclared production of nuclear materials, whereas the PP portion of the goal ensures that generation IV NESs are robust against theft and sabotage. In 2002, the road map of the Generation IV International Forum (GIF) envisioned that the R and D program for PR and PP would have three areas: 1) safeguards and physical protection technology R and D for each GIF system; 2) formulation of PR and PP criteria and metrics; and 3) evaluation of the criteria and metrics. To cover these R and D items, the PR and PP Working Group (PRPPWG) was formed in late 2002 and has since developed a methodology for PR and PP evaluation. In a succession of revisions beginning in 2004, consensus was achieved amongst all participating GIF countries and related organizations (i.e., IAEA and EU), and Revision 6 of the methodology report was approved by GIF for open distribution in 2011. The paper describes in detail the methodology developed by the PRPPWG and discusses its applicability to the sodium-cooled fast reactor (SFR) fuel cycle with pyro processing currently under development in Korea.

  11. Evaluation of long-term creep-fatigue life of stainless steel weldment based on a microstructure degradation model

    International Nuclear Information System (INIS)

    Asayama, Tai; Hasebe, Shinichi

    1997-01-01

    This paper describes a newly developed analytical method of evaluation of creep-fatigue strength of stainless weld metals. Based on the observation that creep-fatigue crack initiates adjacent to the interface of sigma-phase/delta-ferrite and matrix, a mechanistic model which allows the evaluation of micro stress/strain concentration adjacent to the interface was developed. Fatigue and creep damage were evaluated using the model which describes the microstructure after exposed to high temperatures for a long time. Thus it was made possible to predict analytically the long-term creep-fatigue life of stainless steel metals whose microstructure is degraded as a result of high temperature service. (author)

  12. Methodologies for evaluating the proliferation resistance of nuclear fuel cycles

    International Nuclear Information System (INIS)

    Shiotani, Hiroki; Hori, Kei-ichiro; Takeda, Hiroshi

    2001-01-01

    The Japan Nuclear Cycle Development Institute (JNC) believes that the development of future nuclear fuel cycle technology should be conducted with careful consideration given to non-proliferation. JNC is studying methodologies for evaluating proliferation resistance of nuclear fuel cycle technologies. However, it is difficult to establish the methodology for evaluating proliferation resistance since the results greatly depend on the assumption for the evaluation and the surrounding conditions. This study grouped factors of proliferation resistance into categories through reviewing past studies and studied the relationships between the factors. Then, this study tried to find vulnerable nuclear material (plutonium) in some FBR fuel cycles from the proliferation perspective, and calculated the time it takes to convert the materials from various nuclear fuel cycles into pure plutonium metal under some assumptions. The result showed that it would take a long time to convert the nuclear materials from the FBR fuel cycles without plutonium separation. While it is a preliminary attempt to evaluate a technical factor of proliferation resistance as the basis of the institutional proliferation resistance, the JNC hopes that it will contribute to future discussions in this area. (author)

  13. Evaluating Interactive Fatigue Management Workshops for Occupational Health Professionals in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Sheila Ali

    2014-12-01

    Conclusion: Fatigue can lead to severe functional impairment with adverse workplace outcomes. One-day workshops can be effective in training OH professionals in how to diagnose and manage fatigue and CFS. Training may increase general knowledge of fatigue and confidence in fatigue management in an OH setting.

  14. Methodology for evaluating port vulnerability to nuclear smuggling

    International Nuclear Information System (INIS)

    Ek, D.; Gronager, J.R.; Blankenship, J.A.; Martin, D.

    2001-01-01

    Full text: Background: Fueled by an increase in intercepted nuclear smuggling events, the threat of nuclear smuggling has received increased attention in recent years. This attention has resulted in a focused effort to improve the ability to deter or detect smuggling attempts through border crossings, including seaports, airports, and rail and road crossings. These efforts have primarily been focused on installing SNM detectors across vehicle and pedestrian gates entering these ports. However, the effectiveness of this application in deterring or detecting events has not been carefully evaluated. A recent effort was undertaken to evaluate in detail the susceptibility of an international seaport and airport to nuclear smuggling. The evaluation considered a range of adversary profiles to match these against existing and proposed port security measures and equipment. The evaluation was pursued using path analysis methodologies, which were adapted to the port environment. As a result of limited data concerning the effectiveness of patrol, search, and access control procedures at the port, an assessment methodology was developed to estimate these in a standardized fashion. The methodology considers a detailed list of tasks each type of adversary must successfully accomplish for any particular smuggling scenario and path through the port. Within these tasks, locations or times of potential detection are identified. From a look-up table, a detection level (Low, Medium, or High) is assigned to each detection potential based upon the type of detection possible and considering the possible access or authority of each adversary. The overall detection potential in determined as a sum of these individual detection potentials according to the equation: P t ={1-Σ(1-P n ). Where: P t is the total detection potential for an adversary path, and P n is the individual detection at a particular location or time. The evaluation revealed that the current process of installing portals at

  15. Fracture mechanical evaluation of high temperature structure and creep-fatigue defect assessment

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chang Gyu; Kim, Jong Bum; Lee, Jae Han

    2004-02-01

    This study proposed the evaluation procedure of high temperature structures from the viewpoint of fracture mechanics on the cylindrical structure applicable to the KALIMER, which is developed by KAERI. For the evaluation of structural integrity, linear and non-linear fracture mechanics parameters were analyzed. Parameters used in creep defect growth applicable to high temperature structure of liquid metal reactor and the evaluation codes with these parameters were analyzed. The evaluation methods of defect initiation and defect growth which were established in R5/R6 code(UK), JNC method (Japan) and RCC-MR A16(France) code were analyzed respectively. The evaluation procedure of leak before break applicable to KALIMER was preliminarily developed and proposed. As an application example of defect growth, the creep-fatigue defect growth on circumferential throughwall defect in high temperature cylindrical structure was evaluated by RCC-MR A16 and this application technology was established.

  16. Best estimate procedures for fatigue evaluation in the framework of German KTA code

    Energy Technology Data Exchange (ETDEWEB)

    Seichter, Johannes [Siempelkamp Pruef- und Gutachter-Gesellschaft mbH, Dresden (Germany); Reese, Sven H.; Klucke, Dietmar [E.ON Kernkraft GmbH, Hannover (Germany)

    2013-07-01

    By decreasing the level of conservatism in fatigue analyses it is possible to reduce as well fatigue usage factors calculated for EOL (end of life) as 'actual CUF' (cumulative fatigue usage factor) of NPP components considerably. It is the opinion of the authors, that the mentioned best estimate procedures should be used in the course of fatigue assessment to fulfill e.g. the demands of the KTA code with regard to environmental assisted fatigue. (orig.)

  17. An environmental factor approach to account for reactor water effects in light water reactor pressure vessel and piping fatigue evaluations

    International Nuclear Information System (INIS)

    Mehta, H.S.; Gosselin, S.R.

    1996-01-01

    This paper summarizes past and current studies of the environmental fatigue effects in LWR applications. Current Argonne and Japanese research efforts are reviewed and an approach to calculate an environmental correction factor is described. A description of how the proposed approach can be implemented in Section III, NB-3600 and NB-3200-type fatigue evaluations, is presented along with examples of applying the approach to piping (NB-3600) and safe-end fatigue evaluations. These procedures were applied to several BWR and PWR example cases. The results of these case studies indicated that there is a modest increase in calculated fatigue usage, which is considerably less than the results obtained when the NUREG/CR-5999 curves are applied directly

  18. Reservoir shorelines : a methodology for evaluating operational impacts

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, M.; Braund-Read, J.; Musgrave, B. [BC Hydro, Burnaby, BC (Canada)

    2009-07-01

    BC Hydro has been operating hydroelectric facilities for over a century in British Columbia. The integrity and stability of the shorelines and slopes bordering hydroelectric reservoirs is affected by changing water levels in the reservoir, natural processes of flooding, wind and wave action and modification of groundwater levels. Establishing setbacks landward of the shoreline are needed in order to protect useable shoreline property that may be at risk of flooding, erosion or instability due to reservoir operations. Many of the reservoirs in British Columbia are situated in steep, glaciated valleys with diverse geological, geomorphological and climatic conditions and a variety of eroding shorelines. As such, geotechnical studies are needed to determine the operational impacts on reservoir shorelines. Since the 1960s BC Hydro has been developing a methodology for evaluating reservoir impacts and determining the land around the reservoir perimeter that should remain as a right of way for operations while safeguarding waterfront development. The methodology was modified in the 1990s to include geomorphological and geological processes. However, uncertainties in the methodology still exist due to limited understanding of key issues such as rates of erosion and shoreline regression, immaturity of present day reservoir shorelines and impacts of climate change. 11 refs., 1 tab., 7 figs.

  19. The evaluation framework for business process management methodologies

    Directory of Open Access Journals (Sweden)

    Sebastian Lahajnar

    2016-06-01

    Full Text Available In an intense competition in the global market, organisations seek to take advantage of all their internal and external potentials, advantages, and resources. It has been found that, in addition to competitive products and services, a good business also requires an effective management of business processes, which is the discipline of the business process management (BPM. The introduction of the BPM in the organisation requires a thoughtful selection of an appropriate methodological approach, since the latter will formalize activities, products, applications and other efforts of the organisation in this field. Despite many technology-driven solutions of software companies, recommendations of consulting companies, techniques, good practices and tools, the decision on what methodology to choose is anything but simple. The aim of this article is to simplify the adoption of such decisions by building a framework for the evaluation of BPM methodologies according to a qualitative multi-attribute decision-making method. The framework defines a hierarchical decision-making model, formalizes the decision-making process and thus contributes significantly to an independent, credible final decision that is the most appropriate for a specific organisation.

  20. A bench-scale biotreatability methodology to evaluate field bioremediation

    International Nuclear Information System (INIS)

    Saberiyan, A.G.; MacPherson, J.R. Jr.; Moore, R.; Pruess, A.J.; Andrilenas, J.S.

    1995-01-01

    A bench-scale biotreatability methodology was designed to assess field bioremediation of petroleum contaminated soil samples. This methodology was performed successfully on soil samples from more than 40 sites. The methodology is composed of two phases, characterization and experimentation. The first phase is physical, chemical, and biological characterization of the contaminated soil sample. This phase determines soil parameters, contaminant type, presence of indigenous contaminant-degrading bacteria, and bacterial population size. The second phase, experimentation, consists of a respirometry test to measure the growth of microbes indirectly (via generation of CO 2 ) and the consumption of their food source directly (via contaminant loss). Based on a Monod kinetic analysis, the half-life of a contaminant can be calculated. Abiotic losses are accounted for based on a control test. The contaminant molecular structure is used to generate a stoichiometric equation. The stoichiometric equation yields a theoretical ratio for mg of contaminant degraded per mg of CO 2 produced. Data collected from the respirometry test are compared to theoretical values to evaluate bioremediation feasibility

  1. European Healthy Cities evaluation: conceptual framework and methodology.

    Science.gov (United States)

    de Leeuw, Evelyne; Green, Geoff; Dyakova, Mariana; Spanswick, Lucy; Palmer, Nicola

    2015-06-01

    This paper presents the methodology, programme logic and conceptual framework that drove the evaluation of the Fifth Phase of the WHO European Healthy Cities Network. Towards the end of the phase, 99 cities were designated progressively through the life of the phase (2009-14). The paper establishes the values, systems and aspirations that these cities sign up for, as foundations for the selection of methodology. We assert that a realist synthesis methodology, driven by a wide range of qualitative and quantitative methods, is the most appropriate perspective to address the wide geopolitical, demographic, population and health diversities of these cities. The paper outlines the rationale for a structured multiple case study approach, the deployment of a comprehensive questionnaire, data mining through existing databases including Eurostat and analysis of management information generation tools used throughout the period. Response rates were considered extremely high for this type of research. Non-response analyses are described, which show that data are representative for cities across the spectrum of diversity. This paper provides a foundation for further analysis on specific areas of interest presented in this supplement. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Evaluating the Staff at Enterprise: Several Theoretical and Methodological Aspects

    Directory of Open Access Journals (Sweden)

    Girman Alla P.

    2017-03-01

    Full Text Available The article is aimed at generalizing and systematizing various knowledge, related to evaluation of staff, on a common theoretical-methodological basis. Concept, objectives, directions, methods, and indicators for evaluating staff in the contemporary economy were analyzed. The topicality of using the theoretical developments on staff evaluation in actual practice of functioning of enterprises has been substantiated. A new approach to the procedure of evaluation of the total human resource of enterprise, based on the life cycle of organization, has been proposed. On the basis of the proposed scientific algorithmic step-by-step approach to the evaluation of staff, managers of companies can design their own models for staff evaluation, develop its separate elements. Prospects for further researches in this direction involve relation of staff evaluation to the life cycle of employee no less than the life cycle of enterprise. Management of the life cycle of employee represents methods for management of his development that would change the level of the employee’s professional maturity as result of a system impact.

  3. Nuclear data evaluation methodology including estimates of covariances

    Directory of Open Access Journals (Sweden)

    Smith D.L.

    2010-10-01

    Full Text Available Evaluated nuclear data rather than raw experimental and theoretical information are employed in nuclear applications such as the design of nuclear energy systems. Therefore, the process by which such information is produced and ultimately used is of critical interest to the nuclear science community. This paper provides an overview of various contemporary methods employed to generate evaluated cross sections and related physical quantities such as particle emission angular distributions and energy spectra. The emphasis here is on data associated with neutron induced reaction processes, with consideration of the uncertainties in these data, and on the more recent evaluation methods, e.g., those that are based on stochastic (Monte Carlo techniques. There is no unique way to perform such evaluations, nor are nuclear data evaluators united in their opinions as to which methods are superior to the others in various circumstances. In some cases it is not critical which approaches are used as long as there is consistency and proper use is made of the available physical information. However, in other instances there are definite advantages to using particular methods as opposed to other options. Some of these distinctions are discussed in this paper and suggestions are offered regarding fruitful areas for future research in the development of evaluation methodology.

  4. ECSIN's methodological approach for hazard evaluation of engineered nanomaterials

    Science.gov (United States)

    Bregoli, Lisa; Benetti, Federico; Venturini, Marco; Sabbioni, Enrico

    2013-04-01

    The increasing production volumes and commercialization of engineered nanomaterials (ENM), together with data on their higher biological reactivity when compared to bulk counterpart and ability to cross biological barriers, have caused concerns about their potential impacts on the health and safety of both humans and the environment. A multidisciplinary component of the scientific community has been called to evaluate the real risks associated with the use of products containing ENM, and is today in the process of developing specific definitions and testing strategies for nanomaterials. At ECSIN we are developing an integrated multidisciplinary methodological approach for the evaluation of the biological effects of ENM on the environment and human health. While our testing strategy agrees with the most widely advanced line of work at the European level, the choice of methods and optimization of protocols is made with an extended treatment of details. Our attention to the methodological and technical details is based on the acknowledgment that the innovative characteristics of matter at the nano-size range may influence the existing testing methods in a partially unpredictable manner, an aspect which is frequently recognized at the discussion level but oftentimes disregarded at the laboratory bench level. This work outlines the most important steps of our testing approach. In particular, each step will be briefly discussed in terms of potential technical and methodological pitfalls that we have encountered, and which are often ignored in nanotoxicology research. The final aim is to draw attention to the need of preliminary studies in developing reliable tests, a crucial aspect to confirm the suitability of the chosen analytical and toxicological methods to be used for the specific tested nanoparticle, and to express the idea that in nanotoxicology,"devil is in the detail".

  5. ECSIN's methodological approach for hazard evaluation of engineered nanomaterials

    International Nuclear Information System (INIS)

    Bregoli, Lisa; Benetti, Federico; Venturini, Marco; Sabbioni, Enrico

    2013-01-01

    The increasing production volumes and commercialization of engineered nanomaterials (ENM), together with data on their higher biological reactivity when compared to bulk counterpart and ability to cross biological barriers, have caused concerns about their potential impacts on the health and safety of both humans and the environment. A multidisciplinary component of the scientific community has been called to evaluate the real risks associated with the use of products containing ENM, and is today in the process of developing specific definitions and testing strategies for nanomaterials. At ECSIN we are developing an integrated multidisciplinary methodological approach for the evaluation of the biological effects of ENM on the environment and human health. While our testing strategy agrees with the most widely advanced line of work at the European level, the choice of methods and optimization of protocols is made with an extended treatment of details. Our attention to the methodological and technical details is based on the acknowledgment that the innovative characteristics of matter at the nano-size range may influence the existing testing methods in a partially unpredictable manner, an aspect which is frequently recognized at the discussion level but oftentimes disregarded at the laboratory bench level. This work outlines the most important steps of our testing approach. In particular, each step will be briefly discussed in terms of potential technical and methodological pitfalls that we have encountered, and which are often ignored in nanotoxicology research. The final aim is to draw attention to the need of preliminary studies in developing reliable tests, a crucial aspect to confirm the suitability of the chosen analytical and toxicological methods to be used for the specific tested nanoparticle, and to express the idea that in nanotoxicology,'devil is in the detail'.

  6. Methodology for fast evaluation of Bacillus thuringiensis crystal protein content

    Directory of Open Access Journals (Sweden)

    Alves Lúcia M. Carareto

    2000-01-01

    Full Text Available The development of the production and use of Bacillus thuringiensis in Brazil at a commercial scale faces certain difficulties, among them the establishment of efficient methodologies for the quantitation of toxic products to be commercialized. Presently, the amount of toxin is given in percentage by analyzing the samples total protein content. Such methodology however, does not measure the actual amount of active protein present in the product, since most strains express different endotoxin genes and might even produce b-toxin. Since the various types of toxins exhibit different antigenic characteristics, this work has as objective the utilization of fast immunological techniques to quantify the level of crystal protein. Crystal protein produced by a subspecies of Bacillus thuringiensis var. israelensis was purified by ultracentrifugation and utilized to immunize rabbits and to produce hiperimmune sera. Such sera were latter used to evaluate the level of proteins on commercial bioinsecticide and on laboratory cultures of B. thuringiensis through the immunodot technique. The results were obtained by comparison of data obtained from reactions with known concentrations of crystal protein permitting to evaluate the level of such protein on various materials.

  7. Taipower's reload safety evaluation methodology for pressurized water reactors

    International Nuclear Information System (INIS)

    Huang, Ping-Hue; Yang, Y.S.

    1996-01-01

    For Westinghouse pressurized water reactors (PWRs) such as Taiwan Power Company's (TPC's) Maanshan Units 1 and 2, each of the safety analysis is performed with conservative reload related parameters such that reanalysis is not expected for all subsequent cycles. For each reload cycle design, it is required to perform a reload safety evaluation (RSE) to confirm the validity of the existing safety analysis for fuel cycle changes. The TPC's reload safety evaluation methodology for PWRs is based on 'Core Design and Safety Analysis Package' developed by the TPC and the Institute of Nuclear Energy Research (INER), and is an important portion of the 'Taipower's Reload Design and Transient Analysis Methodologies for Light Water Reactors'. The Core Management System (CMS) developed by Studsvik of America, the one-dimensional code AXINER developed by TPC, National Tsinghua University and INER, and a modified version of the well-known subchannel core thermal-hydraulic code COBRAIIIC are the major computer codes utilized. Each of the computer models is extensively validated by comparing with measured data and/or vendor's calculational results. Moreover, parallel calculations have been performed for two Maanshan reload cycles to validate the RSE methods. The TPC's in-house RSE tools have been applied to resolve many important plant operational issues and plant improvements, as well as to verify the vendor's fuel and core design data. (author)

  8. Strategic alternatives ranking methodology: Multiple RCRA incinerator evaluation test case

    International Nuclear Information System (INIS)

    Baker, G.; Thomson, R.D.; Reece, J.; Springer, L.; Main, D.

    1988-01-01

    This paper presents an important process approach to permit quantification and ranking of multiple alternatives being considered in remedial actions or hazardous waste strategies. This process is a methodology for evaluating programmatic options in support of site selection or environmental analyses. Political or other less tangible motivations for alternatives may be quantified by means of establishing the range of significant variables, weighting their importance, and by establishing specific criteria for scoring individual alternatives. An application of the process to a recent AFLC program permitted ranking incineration alternatives from a list of over 130 options. The process forced participation by the organizations to be effected, allowed a consensus of opinion to be achieved, allowed complete flexibility to evaluate factor sensitivity, and resulted in strong, quantifiable support for any subsequent site-selection action NEPA documents

  9. Evaluation of fatigue-ratcheting damage of a pressurised elbow undergoing damage seismic inputs

    International Nuclear Information System (INIS)

    Dang Van, K.

    2000-01-01

    We present a simplified method to calculate the plastic ratchet of elbow-shaped pipes submitted to seismic loading and an internal pressure. This method is simplified in the sense that the value of the ratchet is obtained without the use of finite element method (FEM) calculations. Here we derive a formula and use it to evaluate the fatigue-ratcheting damage of an elbow. This approach is applicable to complex plastic response appropriately described by non-linear kinematics hardening, which is more realistic for stainless steel such as 316-L. (orig.)

  10. Proposal of risk evaluation methodology for hazardous materials transportation

    International Nuclear Information System (INIS)

    Hartman, Luiz Carlos

    2009-01-01

    The increasing concern with the level of risk associated with the transportation of hazardous materials took some international institutions to pledge efforts in the evaluation of risk in regional level. Following this trend, the objective of this work was to analyze the most recent processes of analysis of risks from road transportation of hazardous materials. In the present work 21 methodologies of analysis of risks, developed by some authors and for diverse localities have been evaluated. Two of them, in special, have been reviewed and discussed: a method recently developed by the Swiss Federal Institute of Technology (Nicolet-Monnier and Gheorghe, 1996) and the strategy delineated by the Center for Chemical Process Safety CCPS (1995), taking into consideration the estimate of the individual and social risk. Also, the models of Harwood et al. (1990) and of Ramos (1997), adapted by Hartman (2003) have been applied to the reality of the roads of the state of Sao Paulo. The extension of these methodologies was explored, in order to find its advantages and disadvantages. As a study case the present work considered the ammonia transportation throughout two routes evaluating the reality of the roads of the state of Sao Paulo, including a significant parcel of evaluation in a densely populated area, getting the results using risk, at least, one of the methodologies mentioned above. The innovation proposed by this work was the research, the development and the introduction of two variables to the model considered by Harwood et al. (1990). These variables that influence in the value of the risk are: the age of the driver of truck and the zone of impact that is function type of product, period of the day where the transport was carried and the volume that has been transported. The aim of the proposed modifications is to let the value of the risk more sensible in relation to the type of the product carried and the age of the truck driver. The main related procedural stages

  11. Evaluating abdominal core muscle fatigue: Assessment of the validity and reliability of the prone bridging test.

    Science.gov (United States)

    De Blaiser, C; De Ridder, R; Willems, T; Danneels, L; Vanden Bossche, L; Palmans, T; Roosen, P

    2018-02-01

    The aims of this study were to research the amplitude and median frequency characteristics of selected abdominal, back, and hip muscles of healthy subjects during a prone bridging endurance test, based on surface electromyography (sEMG), (a) to determine if the prone bridging test is a valid field test to measure abdominal muscle fatigue, and (b) to evaluate if the current method of administrating the prone bridging test is reliable. Thirty healthy subjects participated in this experiment. The sEMG activity of seven abdominal, back, and hip muscles was bilaterally measured. Normalized median frequencies were computed from the EMG power spectra. The prone bridging tests were repeated on separate days to evaluate inter and intratester reliability. Significant differences in normalized median frequency slope (NMF slope ) values between several abdominal, back, and hip muscles could be demonstrated. Moderate-to-high correlation coefficients were shown between NMF slope values and endurance time. Multiple backward linear regression revealed that the test endurance time could only be significantly predicted by the NMF slope of the rectus abdominis. Statistical analysis showed excellent reliability (ICC=0.87-0.89). The findings of this study support the validity and reliability of the prone bridging test for evaluating abdominal muscle fatigue. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Design Methodology and Performance Evaluation of New Generation Sounding Rockets

    Directory of Open Access Journals (Sweden)

    Marco Pallone

    2018-01-01

    Full Text Available Sounding rockets are currently deployed for the purpose of providing experimental data of the upper atmosphere, as well as for microgravity experiments. This work provides a methodology in order to design, model, and evaluate the performance of new sounding rockets. A general configuration composed of a rocket with four canards and four tail wings is sized and optimized, assuming different payload masses and microgravity durations. The aerodynamic forces are modeled with high fidelity using the interpolation of available data. Three different guidance algorithms are used for the trajectory integration: constant attitude, near radial, and sun-pointing. The sun-pointing guidance is used to obtain the best microgravity performance while maintaining a specified attitude with respect to the sun, allowing for experiments which are temperature sensitive. Near radial guidance has instead the main purpose of reaching high altitudes, thus maximizing the microgravity duration. The results prove that the methodology at hand is straightforward to implement and capable of providing satisfactory performance in term of microgravity duration.

  13. A methodology for nuclear power plant operational events evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jeferson, E-mail: jeferson@cnen.gov.br [Comissao Nacional de Energia Nuclear (CGRC/CNEN), Rio de janeiro, RJ (Brazil). Coordenacao Geral de Reatores e do Ciclo de Combustivel; Costa, Sergio Dias, E-mail: sergiodiascosta@hotmail.com [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    to identify trends that might pass unnoticed. There are several methodologies for evaluation of operational events, specifically, for the determination of the causes of the event, where the concepts of root cause, direct cause and causal factors, among others. However, the most recent methodology in use in Brazil, date of 2003. The subject is so important that there is national legislation dealing with the theme, also it need of update. The actual regulations establishes criteria for notification of the occurrence of events considered significant for safety and establishes criteria and deadlines for the issuance of the report. Is also discussed the relationship between occurrence of operational events and a potential application for the life extension of the nuclear power plants, considering the regulatory focus, theme quite present in the international field. The present study intends to present a modern, appropriate methodology for evaluation of operational events, focusing on regulatory aspects and verify its applicability to nuclear power plants. Will also be presented a study of the occurrence of events, focusing on the last five years of operation. Finally will be also presented to international trends in development on this area. (author)

  14. A methodology for nuclear power plant operational events evaluation

    International Nuclear Information System (INIS)

    Araujo, Jeferson

    2015-01-01

    to identify trends that might pass unnoticed. There are several methodologies for evaluation of operational events, specifically, for the determination of the causes of the event, where the concepts of root cause, direct cause and causal factors, among others. However, the most recent methodology in use in Brazil, date of 2003. The subject is so important that there is national legislation dealing with the theme, also it need of update. The actual regulations establishes criteria for notification of the occurrence of events considered significant for safety and establishes criteria and deadlines for the issuance of the report. Is also discussed the relationship between occurrence of operational events and a potential application for the life extension of the nuclear power plants, considering the regulatory focus, theme quite present in the international field. The present study intends to present a modern, appropriate methodology for evaluation of operational events, focusing on regulatory aspects and verify its applicability to nuclear power plants. Will also be presented a study of the occurrence of events, focusing on the last five years of operation. Finally will be also presented to international trends in development on this area. (author)

  15. Methodology to evaluation of the density in radiographic image

    International Nuclear Information System (INIS)

    Louzada, M.J.Q.; Pela, C.A.; Belangero, W.D.; Santos-Pinto, R.

    1998-01-01

    This study was designed in order to optimize the optical densitometry technique in radiographic images by the setorization of the characteristic curves of the radiographic films. We used 24 radiographs of a stepped aluminium wedge that were taken without rigorous control development and manually revealed. The densitometric values of the steps images and its thickness, for each radiographic, was utilized to generate its particular mathematics expressions that represent its characteristic densitometric curves and then it were used for setorization. The densitometric values were obtained by a Macbeth TD528 densitometer. The study showed an optimization in the representation of the relationship between the optical density of the steps images of the wedge and its correspondent thickness, provided by the setorization, with mean square error around 10 -5 . This optimization will allow the use of this methodology in quantitative evaluations of bone mass, by radiographic images. (author)

  16. Residual fatigue life evaluation of rail at squats seeds using 3D explicit finite element analysis

    NARCIS (Netherlands)

    Deng, X.; Naeimi, M.; Li, Z.; Qian, Z.

    2014-01-01

    A modeling procedure to predict the residual fatigue life of rail at squats seeds is developed in this article. Two models are involved: a 3D explicit Finite Element (FE) model to compute the stress and strain at squats in rail, and the J-S fatigue damage model to determine the residual fatigue life

  17. Psychometric evaluation of the EORTC computerized adaptive test (CAT) fatigue item pool

    DEFF Research Database (Denmark)

    Petersen, Morten Aa; Giesinger, Johannes M; Holzner, Bernhard

    2013-01-01

    Fatigue is one of the most common symptoms associated with cancer and its treatment. To obtain a more precise and flexible measure of fatigue, the EORTC Quality of Life Group has developed a computerized adaptive test (CAT) measure of fatigue. This is part of an ongoing project developing a CAT...

  18. Development and evaluation of clicker methodology for introductory physics courses

    Science.gov (United States)

    Lee, Albert H.

    Many educators understand that lectures are cost effective but not learning efficient, so continue to search for ways to increase active student participation in this traditionally passive learning environment. In-class polling systems, or "clickers", are inexpensive and reliable tools allowing students to actively participate in lectures by answering multiple-choice questions. Students assess their learning in real time by observing instant polling summaries displayed in front of them. This in turn motivates additional discussions which increase the opportunity for active learning. We wanted to develop a comprehensive clicker methodology that creates an active lecture environment for a broad spectrum of students taking introductory physics courses. We wanted our methodology to incorporate many findings of contemporary learning science. It is recognized that learning requires active construction; students need to be actively involved in their own learning process. Learning also depends on preexisting knowledge; students construct new knowledge and understandings based on what they already know and believe. Learning is context dependent; students who have learned to apply a concept in one context may not be able to recognize and apply the same concept in a different context, even when both contexts are considered to be isomorphic by experts. On this basis, we developed question sequences, each involving the same concept but having different contexts. Answer choices are designed to address students preexisting knowledge. These sequences are used with the clickers to promote active discussions and multiple assessments. We have created, validated, and evaluated sequences sufficient in number to populate all of introductory physics courses. Our research has found that using clickers with our question sequences significantly improved student conceptual understanding. Our research has also found how to best measure student conceptual gain using research-based instruments

  19. EMCAS: An evaluation methodology for safeguards and security systems

    International Nuclear Information System (INIS)

    Eggers, R.F.; Giese, E.W.; Bichl, F.J.

    1987-01-01

    EMCAS is an evaluation methodology for safeguards and security systems. It provides a score card of projected or actual system performance for several areas of system operation. In one area, the performance of material control and accounting and security systems, which jointly defend against the insider threat to divert or steal special nuclear material (SNM) using stealth and deceit, is evaluated. Time-dependent and time-independent risk equations are used for both diversion and theft risk calculations. In the case of loss detection by material accounting, a detailed timeliness model is provided to determine the combined effects of loss detection sensitivity and timeliness on the overall effectiveness of the material accounting detection procedure. Calculated risks take into account the capabilities of process area containment/surveillance, material accounting mass balance tests, and physical protection barriers and procedures. In addition, EMCAS evaluates the Material Control and Accounting (MC and A) System in the following areas: (1) system capability to detect errors in the official book inventory of SNM, using mass balance accounting methods, (2) system capability to prevent errors from entering the nuclear material data base during periods of operation between mass balance tests, (3) time to conduct inventories and resolve alarms, and (4) time lost from production to carry out material control and accounting loss detection activities. 3 figs., 5 tabs

  20. EMCAS, an evaluation methodology for safeguards and security systems

    International Nuclear Information System (INIS)

    Eggers, R.F.; Giese, E.W.; Bichl, F.J.

    1987-01-01

    EMCAS is an evaluation methodology for safeguards and security systems. It provides a score card of projected or actual system performance for several areas of system operation. In one area, the performance of material control and accounting and security systems, which jointly defend against the insider threat to divert or steal special nuclear material (SNM) using stealth and deceit, is evaluated. Time-dependent and time-independent risk equations are used for both diversion and theft risk calculations. In the case of loss detection by material accounting, a detailed timeliness model is provided to determine the combined effects of loss detection sensitivity and timeliness on the overall effectiveness of the material accounting detection procedure. Calculated risks take into account the capabilities of process area containment/surveillance, material accounting mass balance tests, and physical protection barriers and procedures. In addition, EMCAS evaluates the Material Control and Accounting (MCandA) System in the following areas: (1) system capability to detect errors in the official book inventory of SNM, using mass balance accounting methods, (2) system capability to prevent errors from entering the nuclear material data base during periods of operation between mass balance tests, (3) time to conduct inventories and resolve alarms, and (4) time lost from production to carry out material control and accounting loss detection activities

  1. Evaluation of Kinesiophobia and Its Correlations with Pain and Fatigue in Joint Hypermobility Syndrome/Ehlers-Danlos Syndrome Hypermobility Type

    Directory of Open Access Journals (Sweden)

    Claudia Celletti

    2013-01-01

    Full Text Available Ehlers-Danlos syndrome hypermobility type a. k. a. joint hypermobility syndrome (JHS/EDS-HT is a hereditary musculoskeletal disorder associating generalized joint hypermobility with chronic pain. Anecdotal reports suggest a prominent role for kinesiophobia in disease manifestations, but no study has systematically addressed this point. Objective. To investigate the impact of kinesiophobia and its relationship with pain, fatigue, and quality of life in JHS/EDS-HT. Design. Cross-sectional study. Subjects/Patients. 42 patients (40 female and 2 male with JHS/EDS-HT diagnosis following standardized diagnostic criteria were selected. Methods. Disease features were analyzed by means of specific questionnaires and scales evaluating kinesiophobia, pain, fatigue, and quality of life. The relationships among variables were investigated using the Spearman bivariate analysis. Results. Kinesiophobia resulted predominantly in the patients’ sample. The values of kinesiophobia did not correlate with intensity of pain, quality of life, and (or the single component of fatigue. A strong correlation was discovered between kinesiophobia and general severity of fatigue. Conclusions. In JHS/EDS-HT, the onset of pain-avoiding strategies is related to the presence of pain but not to its intensity. The clear-cut correlation between kinesiophobia and severity of fatigue suggests a direct link between musculoskeletal pain and fatigue. In JHS/EDS-HT, the underlying mechanism is likely to be facilitated by primary disease characteristics, including hypotonia.

  2. Evaluation of environmental effect on creep-fatigue of 2 1/4Cr-1Mo steel

    International Nuclear Information System (INIS)

    Yang Beinan; Ishikawa, Akiyoshi; Asada, Yasuhide.

    1991-01-01

    In the present study, a trial evaluation was made to evaluate the environmental effect of air separately from the behavior of material origin. Data with 2 1/4Cr-1Mo steel at 550degC in air were subjected to the evaluation based on data of the steel in high vacuum with a newly developed procedure using the overstress concept. An empirical expression was proposed to describe the environmental effect of air on the creep-fatigue behavior. Following conclusions were obtained in the present study on a separation of the environmental effect of air on a creep-fatigue behavior of 2 1/4Cr-1Mo steel at 550degC. 1) The environmental effect of air reduces a fatigue life, that is, it increases the time-independent damage component of the creep-fatigue. 2) The environmental effect of air brings on the frequency effect which is mainly dependent upon a strain rate or time in a compression going stroke. Other environmental effect on F-S or compression hold-time cycles depends upon the strain rate in compression. 3) The rate-time dependent damage component, that is, the creep damage is reduced by the environmental effect of air. That means a creep-fatigue life recovers in air environment. (author)

  3. Methodology to identify, review, and evaluate components for license renewal

    International Nuclear Information System (INIS)

    Carlson, D.D.; Gregor, F.E.; Walker, R.S.

    1988-01-01

    A methodology has been developed to systematically identify, review, and evaluate plant equipment for license renewal. The method builds upon the existing licensing basis, operating history, and accepted deterministic and probabilistic techniques. Use of these approaches provides a focus for license renewal upon those safety-significant systems and components that are not routinely replaced, refurbished, or subject to detailed inspection as part of the plant's existing test, maintenance, and surveillance programs. Application of the method identified the PWR and BWR systems that should be subjected to detailed license renewal review. Detailed examination of two example systems demonstrates the approach. The review and evaluation of plant equipment for license renewal differ from the initial licensing of the plant. A substantial operating history has been established, the licensing basis has evolved from the original one, and plant equipment has been subject to periodic maintenance and surveillance throughout its life. In consideration of these differences, a basis for license renewal is needed. License renewal should be based upon continuation of the existing licensing basis and recognition of existing programs and operating history

  4. APPETITE CONTROL: METHODOLOGICAL ASPECTS OF THE EVALUATION OF FOODS

    Science.gov (United States)

    Blundell, John; de Graaf, Cees; Hulshof, Toine; Jebb, Susan; Livingstone, Barbara; Lluch, Anne; Mela, David; Salah, Samir; Schuring, Ewoud; van der Knaap, Henk; Westerterp, Margriet

    2013-01-01

    This report describes a set of scientific procedures used to assess the impact of foods and food ingredients on the expression of appetite (psychological and behavioural). An overarching priority has been to enable potential evaluators of health claims about foods to identify justified claims, and to exclude claims that are not supported by scientific evidence for the effect cited. This priority follows precisely from the principles set down in the PASSCLAIM report. (4) The report allows the evaluation of the strength of health claims, about the effects of foods on appetite, which can be sustained on the basis of the commonly used scientific designs and experimental procedures. The report includes different designs for assessing effects on satiation as opposed to satiety,detailed coverage of the extent to which a change in hunger can stand-alone as a measure of appetite control, and an extensive discussion of the statistical procedures appropriate for handling data in this field of research. Since research in this area is continually evolving, new improved methodologies may emerge over time and will need to be incorporated into the framework. One main objective of the report has been to produce guidance on good practice in carrying out appetite research, and not to set down a series of commandments that must be followed. PMID:20122136

  5. An investigation of wall temperature characteristics to evaluate thermal fatigue at a T-junction pipe

    International Nuclear Information System (INIS)

    Miyoshi, Koji; Nakamura, Akira; Utanohara, Yoichi; Takenaka, Nobuyuki

    2014-01-01

    Thermal fatigue cracking may initiate at a T-junction pipe where high and low temperature fluids mix. In this study, wall temperature characteristics at a T-junction pipe were investigated to improve the evaluation method for thermal fatigue. The stainless steel test section consisted of a horizontal main pipe (diameter, 150 mm) and a T-junction connected to a vertical branch pipe (diameter, 50 mm). The inlet flow velocities in the main and branch pipes were set to 0.99 m/s and 0.66 m/s respectively to produce a wall jet pattern in which the jet from the branch pipe was bent by the main pipe flow and made to flow along the pipe wall. The temperature difference was 34.1 K. A total of 148 thermocouples were installed to measure the wall temperature on the pipe inner surface in the downstream region. The maximum of temperature fluctuation intensity on the pipe inner surface was measured as 5% of the fluid temperature difference at the inlets. The dominant frequency of the large temperature fluctuations in the region downstream from z = 0.5D m was equal to 0.2 of the Strouhal number, which was equal to the frequency caused by the vortex streets generated around the jet flow. The large temperature fluctuation was also observed with the period of about 10 s. The fluctuation was caused by spreading of the heated region in the circumferential direction. (author)

  6. Evaluation of protective effect of Aegle marmelos Corr. in an animal model of chronic fatigue syndrome.

    Science.gov (United States)

    Lalremruta, Vanphawng; Prasanna, Gurunath S

    2012-05-01

    To evaluate ethanolic extract of leaves of Aegle marmelos in an experimental animal model of chronic fatigue syndrome for potential therapeutic benefit. Age/weight-matched female Wistar albino rats were grouped into five groups. (Group I- V) (n = 8). Group I served as naïve control and II served as stress control. Except for group I animals, other group animals were subjected to forced swimming every day for 15 minutes to induce a state of chronic fatigue and simultaneously treated with ethanolic extract of Aegle marmelos (EEAM) 150 and 250 mg/kg b.w. and Imipramine (20 mg.kg b.w.), respectively. Duration of immobility, anxiety level and locomotor activity were assessed on day 1, 7, 14 and 21 followed by biochemical estimation of oxidative biomarkers at the end of the study. Treatment with EEAM (150 and 250 mg/kg b.w.) resulted in a statistically significant and dose dependent reduction (P immobility, reduction in anxiety and increase in locomotor activity. Dose dependent and significant reduction in LPO level and increase in CAT and SOD was observed in extract treated animals. The results are suggestive of potential protective effect of A. marmelos against experimentally induced CFS.

  7. Evaluation of creep-fatigue/ environment interaction in Ni-base wrought alloys for HTGR application

    International Nuclear Information System (INIS)

    Hattori, Hiroshi; Kitagawa, Masaki; Ohtomo, Akira

    1986-01-01

    High Temperature Gas-cooled Reactor (HTGR) systems should be designed based on the high temperature structural strength design procedures. On the development of design code, the determination of failure criteria under cyclic loading and severe environments is one of the most important items. By using the previous experimental data for Ni-base wrought alloys, Inconel 617 and Hastelloy XR, several evaluation methods for creep-fatigue interaction were examined for their capability to predict their cyclic loading behavior for HTGR application. At first, the strainrange partitioning method, the frequency modified damage function and the linear damage summation rule were discussed. However, these methods were not satisfactory with the above experimental results. Thus, in this paper, a new fracture criterion, which is a modification of the linear damage summation rule, is proposed based on the experimental data. In this criterion, fracture is considered to occur when the sum of the fatigue damage, which is the function of the applied cyclic strain magnitude, and the modified creep damage, which is the function of the applied cyclic stress magnitude (determined as time devided by cyclic creep rupture time reflecting difference of creep damages by tensile creep and compressive creep), reaches a constant value. This criterion was successfully applied to the life prediction of materials at HTGR temperatures. (author)

  8. Evaluation in health: participatory methodology and involvement of municipal managers.

    Science.gov (United States)

    Almeida, Cristiane Andrea Locatelli de; Tanaka, Oswaldo Yoshimi

    2016-08-04

    To analyze scopes and limits of the use of participatory methodology of evaluation with municipal health managers and administrators. Qualitative research with health policymakers and managers of the Comissão Intergestores Regional (CIR - Regional Interagency Commission) of a health region of the state of Sao Paulo in Brazil. Representatives from seven member cities participated in seven workshops facilitated by the researchers, with the aim of assessing a specific problem of the care line, which would be used as a tracer of the system integrality. The analysis of the collected empirical material was based on the hermeneutic-dialectic methodology and aimed at the evaluation of the applied participatory methodology, according to its capacity of promoting a process of assessment capable to be used as a support for municipal management. With the participatory approach of evaluation, we were able to promote in-depth discussions with the group, especially related to the construction of integral care and to the inclusion of the user's perspective in decision-making, linked to the search for solution to concrete problems of managers. By joint exploration, the possibility of using data from electronic information systems was opened, as well as information coming directly from the users of the services, to enhance discussions and negotiations between partners. The participants were disbelievers of the replication potential of this type of evaluation without the direct monitoring of the academy, given the difficulty of organizing the process in everyday life, already taken by emergency and political issues. Evaluations of programs and services carried out within the Regional Interagency Commission, starting from the local interest and facilitating the involvement of its members by the use of participatory methodologies, can contribute to the construction of integral care. To the extent that the act of evaluating stay invested with greater significance to the local actors

  9. Evaluation methodology based on physical security assessment results: a utility theory approach

    International Nuclear Information System (INIS)

    Bennett, H.A.; Olascoaga, M.T.

    1978-03-01

    This report describes an evaluation methodology which aggregates physical security assessment results for nuclear facilities into an overall measure of adequacy. This methodology utilizes utility theory and conforms to a hierarchical structure developed by the NRC. Implementation of the methodology is illustrated by several examples. Recommendations for improvements in the evaluation process are given

  10. A Methodology for Evaluating Quantitative Nuclear Safety Culture Impact

    International Nuclear Information System (INIS)

    Han, Kiyoon; Jae, Moosung

    2015-01-01

    Through several accidents of NPPs including the Fukushima Daiichi in 2011 and Chernobyl accidents in 1986, nuclear safety culture has been emphasized in reactor safety world-widely. In Korea, KHNP evaluates the safety culture of NPP itself. KHNP developed the principles of the safety culture in consideration of the international standards. A questionnaire and interview questions are also developed based on these principles and it is used for evaluating the safety culture. However, existing methodology to evaluate the safety culture has some disadvantages. First, it is difficult to maintain the consistency of the assessment. Second, the period of safety culture assessment is too long (every two years) so it has limitations in preventing accidents occurred by a lack of safety culture. Third, it is not possible to measure the change in the risk of NPPs by weak safety culture since it is not clearly explains the effect of safety culture on the safety of NPPs. In this study, Safety Culture Impact Assessment Model (SCIAM) is developed overcoming these disadvantages. In this study, SCIAM which overcoming disadvantages of exiting safety culture assessment method is developed. SCIAM uses SCII to monitor the statues of the safety culture periodically and also uses RCDF to quantify the safety culture impact on NPP's safety. It is significant that SCIAM represents the standard of the healthy nuclear safety culture, while the exiting safety culture assessment presented only vulnerability of the safety culture of organization. SCIAM might contribute to monitoring the level of safety culture periodically and, to improving the safety of NPP

  11. A Methodology for Evaluating Quantitative Nuclear Safety Culture Impact

    Energy Technology Data Exchange (ETDEWEB)

    Han, Kiyoon; Jae, Moosung [Hanyang University, Seoul (Korea, Republic of)

    2015-05-15

    Through several accidents of NPPs including the Fukushima Daiichi in 2011 and Chernobyl accidents in 1986, nuclear safety culture has been emphasized in reactor safety world-widely. In Korea, KHNP evaluates the safety culture of NPP itself. KHNP developed the principles of the safety culture in consideration of the international standards. A questionnaire and interview questions are also developed based on these principles and it is used for evaluating the safety culture. However, existing methodology to evaluate the safety culture has some disadvantages. First, it is difficult to maintain the consistency of the assessment. Second, the period of safety culture assessment is too long (every two years) so it has limitations in preventing accidents occurred by a lack of safety culture. Third, it is not possible to measure the change in the risk of NPPs by weak safety culture since it is not clearly explains the effect of safety culture on the safety of NPPs. In this study, Safety Culture Impact Assessment Model (SCIAM) is developed overcoming these disadvantages. In this study, SCIAM which overcoming disadvantages of exiting safety culture assessment method is developed. SCIAM uses SCII to monitor the statues of the safety culture periodically and also uses RCDF to quantify the safety culture impact on NPP's safety. It is significant that SCIAM represents the standard of the healthy nuclear safety culture, while the exiting safety culture assessment presented only vulnerability of the safety culture of organization. SCIAM might contribute to monitoring the level of safety culture periodically and, to improving the safety of NPP.

  12. THE STUDY OF ORGANIZATIONAL CULTURE: METHODOLOGY FOR QUANTITATIVE EVALUATION AND ANALYSIS

    Directory of Open Access Journals (Sweden)

    To Thu Trang

    2014-01-01

    Full Text Available This article discusses the concept: methodof evaluation organizational culture, qualitative and quantitative assessment methodology and lists the basic methodologyfor assessing organizational culture. Fullydescribe professor Denison’s methodology for assessing organizational culture.

  13. Evaluation of Mechanical Properties and Fatigue Behavior of STS 304L due to Plastic Working

    Energy Technology Data Exchange (ETDEWEB)

    Shim, Hyun-Bo [Yeungnam Univ., Daegu (Korea, Republic of); Kim, Young-Kyun [KOGAS Research Institute, Seoul (Korea, Republic of); Suh, Chang-Min [Kyungpook Nat’l Univ., Daegu (Korea, Republic of)

    2017-07-15

    The purpose of this study is to investigate the influence of the cold reduction rate and an ultrasonic fatigue test (UFT) on the fatigue behaviors of STS 304L. The tensile strength, yield strength, hardness value and fatigue limit in the UFT fatigue test linearly increased as thickness decreased from 1.5 mm to 1.1 mm, as the cold reduction rate of STS 304L increased. As a result of the UFT fatigue test (R = -1) of four specimens, the fatigue limit of the S-N curve formed a knee point in the region of 10{sup 6}, and the 2nd fatigue limit caused by giga cycle fatigue did not appeared. In the case of t = 1.1 mm, the highest fatigue limit was 345 MPa, which was 64.3% higher than the original material (t = 1.5 mm). As a result of the UFT fatigue test of STS 304L, many small surface cracks occurred, grown, coalesced while tearing.

  14. Optimal Fatigue Testing

    DEFF Research Database (Denmark)

    Faber, Michael Havbro; Sørensen, John Dalsgaard; Kroon, I. B.

    1993-01-01

    life experiments for the same purpose. The methodology is basedon modern probabilistic concepts amd classical decision theory. The special case where the fatigue life experiments are given in terms of SN curves is considered in Particular. The proposed techniques are illustrated by an example.......This paper considers the reassessment of the reliability of tubular joints subjected to fatigue load. The reassessment is considered in two parts namely the task of utilizing new experimental data on fatigue life to update the reliability of the tubular joint ant the task of planning new fatigue...

  15. Review of effectiveness-evaluation methodologies for safeguards and security systems

    International Nuclear Information System (INIS)

    Dowdy, E.J.; Mangan, D.L.

    1982-06-01

    We discuss the factors that influence the effectiveness of safeguards and security measures and the characteristics required of effectiveness evaluation methodologies. Within this context and from a utility standpoint, we review those effectiveness evaluation methodologies that have been developed. Our principal recommendation concerns the application and concomitant validation of existing methodologies. This recommendation derives from our conclusion that there has been a gross imbalance between the effort spent on methodology development and the application of those methodologies. Only for those safeguards measures that do not seem to be covered by existing methodologies or that seem to be inadequately covered do we suggest development. 44 references

  16. Methodology development for statistical evaluation of reactor safety analyses

    International Nuclear Information System (INIS)

    Mazumdar, M.; Marshall, J.A.; Chay, S.C.; Gay, R.

    1976-07-01

    In February 1975, Westinghouse Electric Corporation, under contract to Electric Power Research Institute, started a one-year program to develop methodology for statistical evaluation of nuclear-safety-related engineering analyses. The objectives of the program were to develop an understanding of the relative efficiencies of various computational methods which can be used to compute probability distributions of output variables due to input parameter uncertainties in analyses of design basis events for nuclear reactors and to develop methods for obtaining reasonably accurate estimates of these probability distributions at an economically feasible level. A series of tasks was set up to accomplish these objectives. Two of the tasks were to investigate the relative efficiencies and accuracies of various Monte Carlo and analytical techniques for obtaining such estimates for a simple thermal-hydraulic problem whose output variable of interest is given in a closed-form relationship of the input variables and to repeat the above study on a thermal-hydraulic problem in which the relationship between the predicted variable and the inputs is described by a short-running computer program. The purpose of the report presented is to document the results of the investigations completed under these tasks, giving the rationale for choices of techniques and problems, and to present interim conclusions

  17. Russian Сonsumer Sector: Methodology of Evaluation

    Directory of Open Access Journals (Sweden)

    Gavriil Aleksandrovich Agarkov

    2015-12-01

    Full Text Available The article describes the methodology for estimating the Russia’s consumer sector and the effect of its application. The monitoring procedure of the Russian consumer sector groups indicators into two units: the unit of the estimation of consumer goods and the services market estimation unit. The estimation unit of consumer goods is composed of two modules: food products and non-food products. This module offers two components that provide an estimation of the consumer sector: marketing (estimates the accessibility of retail trade and services for end users and production (estimates the domestic manufacture. The results of the estimation show general improvements in the consumer sector in the period of 2000–2014, but overall development is evaluated as low. The analysis revealed that the financing is growing faster than the quality indices of development. As an example, the financing of agriculture has increased by 1.5 times over 15 years (against comparable prices from 2000, while agricultural production has not changed. Another most pressing challenge is the weak differentiation of the Russian economy, as evidenced by the low rates of non-food production (availability of non-foods of own production remains at a low level and averages 20 %. The results of the estimation suggest the need to reform the regulation of the sector primarily concerning priorities for its development and improvement of financial and economic mechanisms to achieve them.

  18. A theoretical evaluation of the oxygen concentration in a corrosion-fatigue crack

    International Nuclear Information System (INIS)

    Turnbull, A.

    1981-01-01

    The oxygen concentration in a corrosion-fatigue crack has been evaluated theoretically by assuming that oxygen was consumed by cathodic reduction on the walls of the crack and mass transport occurred by diffusion and advection (forced convection), with the latter resulting from the sinusoidal variation of the displacement of the crack walls. By using parameters relevant to a compact tension specimen, the time-dependent distribution of the oxygen concentration in the crack was calculated as a function of ΔK (the range of the stress intensity factor), R-value (minimum load/maximum load), frequency, crack length, and electrode potential. The influence of advection was to significantly enhance the mass transport of oxygen in the crack compared with ''diffusion-only'' even at low frequencies and low ΔK. Regions in the crack were identified in which advection dominance or diffusion dominance of the mass transport of oxygen occurred

  19. Creep-fatigue life property of FBR high-temperature structural materials under tension-torsion loading and life evaluation method

    International Nuclear Information System (INIS)

    Ogata, Takashi; Nitta, Akito

    1994-01-01

    Creep-fatigue damage in high temperature structural components in a FBR progress under multiaxial stress condition depending on their operating conditions and configuration. Therefore, multiaxial stress effects on creep-fatigue damage evolution must be clarified to make precise creep-fatigue damage evaluation of these components. In this study, creep-fatigue tests in FBR high temperature materials such as SUS304, 316FR stainless steels and a modified 9Cr steel were conducted under biaxial stress subjecting tension-compression and torsion loading, in order to examine biaxial stress effects on failure mechanism and life property, and to discuss creep-fatigue life evaluation methods under biaxial stress. Main results obtained in this study are summarized as follows: 1. The main cracks under cyclic torsion loading propagated by shear mode in three materials. But intergranular failure was occurred in SUS304 and 316FR, and transgranular failure was observed in Mod.9Cr steel. 2. Nonlinear damage accumulation model proposed based on uniaxial creep-fatigue test results was extended to apply for creep-fatigue damage evaluation under biaxial stress state by considering the biaxial stress effects on fatigue and creep damage evolution. 3. It was confirmed that creep-fatigue life under biaxial stress could be predicted by the extended evaluation method with higher accuracy than existing methods. (author)

  20. Effects of fatigue on the chemical and mechanical degradation of model stent sub-units.

    Science.gov (United States)

    Dreher, Maureen L; Nagaraja, Srinidhi; Batchelor, Benjamin

    2016-06-01

    Understanding the fatigue and durability performance of implantable cardiovascular stents is critical for assessing their performance. When the stent is manufactured from an absorbable material, however, this durability assessment is complicated by the transient nature of the device. Methodologies for evaluating the fatigue performance of absorbable stents while accurately simulating the degradation are limited and little is known about the interaction between fatigue and degradation. In this study, we investigated the fatigue behavior and effect of fatigue on the degradation rate for a model absorbable cardiovascular stent. Custom v-shaped stent sub-units manufactured from poly(L-lactide), i.e., PLLA, were subjected to a simultaneous fatigue and degradation study with cycle counts representative of one year of expected in vivo use. Fatigue loading was carried out such that the polymer degraded at a rate that was aligned with a modest degree of fatigue acceleration. Control, un-loaded specimens were also degraded under static immersion conditions representative of simulated degradation without fatigue. The study identified that fatigue loading during degradation significantly increased specimen stiffness and lowered the force at break. Fatigue loading also significantly increased the degree of molecular weight decline highlighting an interaction between mechanical loading and chemical degradation. This study demonstrates that fatigue loading during degradation can affect both the mechanical properties and the chemical degradation rate. The results are important for defining appropriate in vitro degradation conditions for absorbable stent preclinical evaluation. Published by Elsevier Ltd.

  1. A dynamic systems engineering methodology research study. Phase 2: Evaluating methodologies, tools, and techniques for applicability to NASA's systems projects

    Science.gov (United States)

    Paul, Arthur S.; Gill, Tepper L.; Maclin, Arlene P.

    1989-01-01

    A study of NASA's Systems Management Policy (SMP) concluded that the primary methodology being used by the Mission Operations and Data Systems Directorate and its subordinate, the Networks Division, is very effective. Still some unmet needs were identified. This study involved evaluating methodologies, tools, and techniques with the potential for resolving the previously identified deficiencies. Six preselected methodologies being used by other organizations with similar development problems were studied. The study revealed a wide range of significant differences in structure. Each system had some strengths but none will satisfy all of the needs of the Networks Division. Areas for improvement of the methodology being used by the Networks Division are listed with recommendations for specific action.

  2. Employing various metallography methods at high temperature alloy fatigue tests evaluation

    Directory of Open Access Journals (Sweden)

    Juraj Belan

    2016-12-01

    Full Text Available . Microstructures of superalloys have dramatically changed throughout the years, as modern technology of its casting or forging has become more sophisticated. The first superalloys have polyedric microstructure consisting of gamma solid solution, some fraction of gamma prime and of course grain boundaries. As demands on higher performance of aero jet engine increases, the changes in superalloys microstructure become more significant. A further step in microstructure evolution was directionally solidified alloys with columnar gamma prime particles. The latest microstructures are mostly monocrystalline, oriented in [001] direction of FCC gamma matrix. All microstructure changes bring necessity of proper preparation and evaluation of microstructure. Except for the already mentioned structures have gamma double prime and various carbides form can be seen. These structural parameters have mainly positive influence on important mechanical properties of superalloys. The paper deals with a microstructural evaluation of both groups of alloys – cast and as well as wrought. Microstructure evaluation helps to describe mechanism at various loading and failure of progressive superalloys. Such an example where microstructure evaluation is employed is fractography of failure surfaces after fatigue tests, which are examples of metallography evaluation described in this paper as a secondary objective.

  3. Fatigue Damage Evaluation of Short Carbon Fiber Reinforced Plastics Based on Phase Information of Thermoelastic Temperature Change.

    Science.gov (United States)

    Shiozawa, Daiki; Sakagami, Takahide; Nakamura, Yu; Nonaka, Shinichi; Hamada, Kenichi

    2017-12-06

    Carbon fiber-reinforced plastic (CFRP) is widely used for structural members of transportation vehicles such as automobile, aircraft, or spacecraft, utilizing its excellent specific strength and specific rigidity in contrast with the metal. Short carbon fiber composite materials are receiving a lot of attentions because of their excellent moldability and productivity, however they show complicated behaviors in fatigue fracture due to the random fibers orientation. In this study, thermoelastic stress analysis (TSA) using an infrared thermography was applied to evaluate fatigue damage in short carbon fiber composites. The distribution of the thermoelastic temperature change was measured during the fatigue test, as well as the phase difference between the thermoelastic temperature change and applied loading signal. Evolution of fatigue damage was detected from the distribution of thermoelastic temperature change according to the thermoelastic damage analysis (TDA) procedure. It was also found that fatigue damage evolution was more clearly detected than before by the newly developed thermoelastic phase damage analysis (TPDA) in which damaged area was emphasized in the differential phase delay images utilizing the property that carbon fiber shows opposite phase thermoelastic temperature change.

  4. Residual stress evaluation and fatigue life prediction in the welded joint by X-ray diffraction

    International Nuclear Information System (INIS)

    Yoo, Keun Bong; Kim, Jae Hoon

    2009-01-01

    In the fossil power plant, the reliability of the components which consist of the many welded parts depends on the quality of welding. The residual stress is occurred by the heat flux of high temperature during weld process. This decreases the mechanical properties as the strength of fatigue and fracture or occurs the stress corrosion cracking and fatigue fracture. The residual stress of the welded part in the recently constructed power plants has been the cause of a variety of accidents. The objective of this study is measurement of the residual stress by X-ray diffraction method and to estimate the feasibility of this application for fatigue life assessment of the high-temperature pipeline. The materials used for the study is P92 steel for the use of high temperature pipe on super critical condition. The test results were analyzed by the distributed characteristics of residual stresses and the Full Width at Half Maximum intensity (FWHM) in x-ray diffraction intensity curve. Also, X-ray diffraction tests using specimens simulated low cycle fatigue damage were performed in order to analyze fatigue properties when fatigue damage conditions become various stages. As a result of X-ray diffraction tests for specimens simulated fatigue damages, we conformed that the ratio of the FWHM due to fatigue damage has linear relationship with fatigue life ratio algebraically. From this relationships, it was suggested that direct expectation of the life consumption rate was feasible.

  5. Evaluation of psychological and physiological predictors of fatigue in patients with COPD

    Directory of Open Access Journals (Sweden)

    Bidgood Penelope L

    2009-10-01

    Full Text Available Abstract Background Fatigue in COPD impairs functional status; however there are few studies examining mechanistic pathways of this symptom. The aims of this study are to compare fatigue between COPD patients and healthy age-matched subjects, and to identify predictors of fatigue in COPD. Methods Seventy four COPD patients, mean age 69.9 (49-87 yrs, mean (SD % predicted FEV1 46.5 (20.0 % and FEV1/FVC ratio 0.45 (0.13 and 35 healthy subjects, mean age 67.1 (50-84 yrs completed the Multidimensional Fatigue Inventory (MFI 20. Patients' assessment included Depression (HADS, lung function, BMI, muscle strength, incremental shuttle walk test (ISWT, exercise oxygen saturation (SpO2, Borg breathlessness (CR-10 and exertion (RPE. Serum level of Interleukin 6 (IL-6 was recorded. Differences in MFI 20 between groups were examined and predictors of fatigue identified using logistic regression. Results Significant differences (p 2 (R2 = .62; of Physical Fatigue: depression, % predicted FEV1, ISWT and age (R2 = .57; Reduced Activity: % predicted FEV1, BMI and depression (R2 = .36; Reduced Motivation: RPE, depression and end SpO2 (R2 = .37 and Mental Fatigue: depression and end SpO2 (R2 = .38. Conclusion All dimensions of fatigue were higher in COPD than healthy aged subjects. Predictive factors differ according to the dimension of fatigue under investigation. COPD-RF is a multi component symptom requiring further consideration.

  6. Study on creep-fatigue life improvement and life evaluation of 316FR stainless steels

    International Nuclear Information System (INIS)

    Kobayashi, Kazuo; Yamaguchi, Koji; Yamazaki, Masayoshi; Hongo, Hiromichi; Nakazawa, Takanori; Date, Shingo; Tendo, Masayuki

    2000-01-01

    Creep rupture and creep-fatigue interaction tests were conducted at 550deg C for modified 316FR austenitic stainless steels in order to improve the creep-fatigue lives. Reducing the carbon contents from 0.01% to 0.002 or 0.003% and finning the grain size were effective for increasing the creep-fatigue lives and the creep rupture ductilities. From these results, an estimation method of the creep-fatigue lives by using the creep rupture ductilities in the modified 316FR steels was proposed. (author)

  7. Hand Fatigue Analysis Using Quantitative Evaluation of Variability in Drawing Patterns

    Directory of Open Access Journals (Sweden)

    mohamadali Sanjari

    2015-02-01

    Full Text Available Background & aim: Muscle fatigue is defined as the reduced power generation capacity of a muscle or muscle group after activity which can lead to a variety of lesions. The purpose of the present study was to define the fatigue analysis by quantitative analysis using drawing patterns. Methods: the present cross-sectional study was conducted on 37 healthy volunteers (6 men and 31 women aged 18-30 years. Before & immediately after a fatigue protocol, quantitative assessment of hand drawing skills was performed by drawing repeated, overlapping, and concentric circles. The test was conducted in three sessions with an interval of 48-72 hours. Drawing was recorded by a digital tablet. Data were statistically analyzed using paired t-test and repeated measure ANOVA. Result: In drawing time series data analysis, at fatigue level of 100%, the variables standard deviation along x axis (SDx, standard deviation of velocity on both x and y axis (SDVx and SDVy and resultant vector velocity standard deviation (SDVR, showed significant differences after fatigue (P<0.05. In comparison of variables after the three fatigue levels, SDx showed significant difference (P<0.05. Conclusions: structurally full fatigue showed significant differences with other levels of fatigue, so it contributed to significant variability in drawing parameters. The method used in the present study recognized the fatigue in high frequency motion as well.

  8. Current state of low-cycle fatigue research based on multiaxial stress intensity and its challenges. Part 1. Focusing on low-cycle fatigue strength evaluation method of elbow piping subjected to in-plane cyclic bending displacement load

    International Nuclear Information System (INIS)

    Urabe, Yoshio

    2017-01-01

    The R and D of fatigue strength at multiaxial stress intensity is recognized to become extremely important in the future in terms of the elaboration of low-cycle fatigue evaluation of various structures including piping systems and reflection on those standards. This paper focuses on the evaluation method developed by the author, namely cumulative damage rule in consideration of multiaxial stress intensity, and explains the concept and the results of verification and evaluation. It also discusses the engineering problems of the current low cycle fatigue assessment technology that were clarified in the process of developing low-cycle fatigue assessment method based on multiaxial stress intensity. The conservative lifespan and somewhat more conservative actual lifetime of elbow piping can be estimated by the conventional 'revised universal slope method' and 'advanced revised universal slope method.' However, these are empirical rules, and the theoretical basis is not clear. From 'cumulative damage rule in consideration of multiaxial stress intensity,' the author calculated furthermore 'low cycle fatigue evaluation formula based on cumulative damage rule in consideration of multi-axial stress intensity,' and examined it. As a result, an evaluation formula that can reasonably assume the equivalent thermoplastic strain range could be obtained at half of the repeat count as targeted. Furthermore, at the stage where future high precision FEM analysis can be used, direct low-cycle fatigue life curve can be established. (A.O.)

  9. An evaluation on fatigue crack growth in a fine-grained isotropic graphite

    Energy Technology Data Exchange (ETDEWEB)

    Wang Hongtao; Sun Libin [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Li Chenfeng [College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP (United Kingdom); Shi Li [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Wang Haitao, E-mail: wanght@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer The propagation of micro- and macro-fatigue cracks in IG-11 graphite was studied. Black-Right-Pointing-Pointer The curves of the fatigue crack growth rate versus the SIF range show three stages. Black-Right-Pointing-Pointer The fatigue microcrack propagation is very sensitive to graphite's microstructures. Black-Right-Pointing-Pointer Graphite's microstructures have no significant impact on fatigue macrocrack growth. Black-Right-Pointing-Pointer The fatigue fracture surface indicates the fracture mechanism of the IG-11 graphite. - Abstract: The aim of this paper is to investigate the mechanism of fatigue crack propagation in IG-11 graphite, and determine the crack growth rate in relation to the stress level. Experimental studies were performed at both micro and macro scales. For fatigue microcrack propagation, single-edge-notch specimens were chosen for testing and the fatigue crack growth was measured in situ with a scanning electron microscope. For fatigue macrocrack propagation, CT specimens were used and the fatigue crack growth was measured with a high-accuracy optic microscope. Combining the two groups of experimental results, the following conclusions are derived: (1) The heterogeneous microstructures of the graphite material have significant impact on the fatigue microcrack growth, while their influence on fatigue macrocrack growth is very limited. (2) The relationship between the fatigue crack growth rate and the crack-tip stress intensity factor range can be expressed in the form of Paris formulae, which contains three stages: an initial rising part with a small slope, an abrupt rise with a very large acceleration, and a short final part with a small slope. (3) The fatigue fracture surface of the graphite material contains considerable sliding of leaf-shape graphite flakes combined with small cotton-shape plastic deformations. These sliding traces are approximately aligned at 45 Degree-Sign , showing the

  10. An evaluation on fatigue crack growth in a fine-grained isotropic graphite

    International Nuclear Information System (INIS)

    Wang Hongtao; Sun Libin; Li Chenfeng; Shi Li; Wang Haitao

    2012-01-01

    Highlights: ► The propagation of micro- and macro-fatigue cracks in IG-11 graphite was studied. ► The curves of the fatigue crack growth rate versus the SIF range show three stages. ► The fatigue microcrack propagation is very sensitive to graphite's microstructures. ► Graphite's microstructures have no significant impact on fatigue macrocrack growth. ► The fatigue fracture surface indicates the fracture mechanism of the IG-11 graphite. - Abstract: The aim of this paper is to investigate the mechanism of fatigue crack propagation in IG-11 graphite, and determine the crack growth rate in relation to the stress level. Experimental studies were performed at both micro and macro scales. For fatigue microcrack propagation, single-edge-notch specimens were chosen for testing and the fatigue crack growth was measured in situ with a scanning electron microscope. For fatigue macrocrack propagation, CT specimens were used and the fatigue crack growth was measured with a high-accuracy optic microscope. Combining the two groups of experimental results, the following conclusions are derived: (1) The heterogeneous microstructures of the graphite material have significant impact on the fatigue microcrack growth, while their influence on fatigue macrocrack growth is very limited. (2) The relationship between the fatigue crack growth rate and the crack-tip stress intensity factor range can be expressed in the form of Paris formulae, which contains three stages: an initial rising part with a small slope, an abrupt rise with a very large acceleration, and a short final part with a small slope. (3) The fatigue fracture surface of the graphite material contains considerable sliding of leaf-shape graphite flakes combined with small cotton-shape plastic deformations. These sliding traces are approximately aligned at 45°, showing the main cause of the fatigue fracture is the shear stress. There are also a large amount of secondary cracks inside unit cells and on cell walls

  11. A pilot mixed-methods evaluation of MS INFoRm: a self-directed fatigue management resource for individuals with multiple sclerosis.

    Science.gov (United States)

    Akbar, Nadine; Turpin, Karen; Petrin, Julie; Smyth, Penny; Finlayson, Marcia

    2018-06-01

    Fatigue management interventions for individuals with multiple sclerosis (MS) often feature structured programmes requiring repeated, in-person attendance that is not possible for all individuals. We sought to determine whether MS INFoRm, a self-directed fatigue management resource for individuals with MS, was worth further, more rigorous evaluation. Our indicators of worthiness were actual use of the resource by participants over 3 months, reductions in fatigue impact and increases in self-efficacy, and participant reports of changes in fatigue management knowledge and behaviours. This was a single-group, mixed-methods, before-after pilot study in individuals with MS reporting mild to moderate fatigue. Thirty-five participants were provided with MS INFoRm by a USB flash drive to use at home for 3 months, on their own volition. Twenty-three participants completed all standardized questionnaires, semi-structured interviews and study process measures. Participants reported actively using MS INFoRm over the 3-month study period (median total time spent using MS INFoRm=315 min) as well as significantly lower overall fatigue impact (Modified Fatigue Impact Scale: t=2.6, P=0.01), increased knowledge of MS fatigue (z=-2.8, P=0.01) and greater confidence in managing MS fatigue (z=-3.3, P=0.001). Individuals with significant reductions in fatigue impact also reported behavioural changes including tracking fatigue, better communication with others, greater awareness, improved quality of life and being more proactive. This study provides evidence that further rigorous evaluation of MS INFoRm, a self-directed resource for managing fatigue, is worth pursuing.

  12. Evaluation of Variation in Residual Strength of Carbon Fiber Reinforced Plastic Plate with a Hole Subjected to Fatigue Load

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Young; Kang, Min Sung; Koo, Jae Mean; Seok, Chang Sung [Sungkyunkwan University, Seoul (Korea, Republic of)

    2010-10-15

    CFRP (Carbon Fiber Reinforced Plastic) has received considerable attention in various fields as a structural material, because of its high specific strength, high specific stiffness, excellent design flexibility, favorable chemical properties, etc. Most products consisting of several parts are generally assembled by mechanical joining methods (using rivets, bolts, pins, etc.). Holes must be drilled in the parts to be joined, and the strength of the components subjected to static and fatigue loads caused by stress concentration must be decreased. In this study, we experimentally evaluated the variation in the residual strength of a holenotched CFRP plate subjected to fatigue load. We repeatedly subjected the hole-notched specimen to fatigue load for a certain number of cycles, and then we investigated the residual strength of the hole-notched specimen by performing the fracture test. From the results of the test, we can observe the initiation of a directional crack caused by the applied fatigue load. Further, we observed that the residual strength increases with a decrease in the notch effect due to this crack. It was evaluated that the residual strength increases to a certain level and subsequently decreases. This variation in the residual strength was represented by a simple equation by using a model of the decrease in residual strength for plain plate, which was developed by Reifsnider and a stress redistribution model for hole-notched plate, which was developed by Yip.

  13. Methodology for economic evaluation of software development projects

    International Nuclear Information System (INIS)

    Witte, D.M.

    1990-01-01

    Many oil and gas exploration and production companies develop computer software in-house or with contract programmers to support their exploration activities. Software development projects compete for funding with exploration and development projects, though most companies lack valid comparison measures for the two types of projects. This paper presents a methodology of pro form a cash flow analysis for software development proposals intended for internal use. This methodology, based on estimates of development and support costs, exploration benefits, and probability of successful development and implementation, can be used to compare proposed software development projects directly with competing exploration proposals

  14. Microstructure, Tensile Strength and Probabilistic Fatigue Life Evaluation of Gray Cast Iron

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Yong Hyeon; Han, Seung-Wook; Choi, Nak-Sam [Hanyang Univ., Seoul (Korea, Republic of)

    2017-08-15

    High-grade gray cast iron (HCI350) was prepared by adding Cr, Mo and Cu to the gray cast iron (GC300). Their microstructure, mechanical properties and fatigue strength were studied. Cast iron was made from round bar and plate-type castings, and was cut and polished to measure the percentage of each microstructure. The size of flake graphite decreased due to additives, while the structure of high density pearlite increased in volume percentage improving the tensile strength and fatigue strength. Based on the fatigue life data obtained from the fatigue test results, the probability - stress - life (P-S-N) curve was calculated using the 2-parameter Weibull distribution to which the maximum likelihood method was applied. The P-S-N curve showed that the fatigue strength of HCI350 was significantly improved and the dispersion of life data was lower than that of GC300. However, the fatigue life according to fatigue stress alleviation increased further. Data for reliability life design was presented by quantitatively showing the allowable stress value for the required life cycle number using the calculated P-S-N curve.

  15. Destination brands and website evaluation: a research methodology

    Directory of Open Access Journals (Sweden)

    J Fernández-Cavia

    2013-10-01

    Full Text Available Introduction:The World Wide Web has become the primary instrument used by tourists in order to search for information. As a result, tourism websites pertaining to destinations need to be appealing and must convey their brand image in an appropriate, effective manner. However, there is no methodology in place to assess the quality and communicative effectiveness of destination websites that is scientifically sound and universally accepted. The development of such a methodology is one of the tasks we have proposed within the framework of the research project: “New strategies for advertising and promoting Spanish tourism brands online” (CSO2008-02627, funded by the Spanish Ministry of Science and Innovation. Method: The project team have developed an interdisciplinary, all-embracing analysis template combining certain automated analyses with other qualitative and quantitative ones. The template comprises a total of 12 subject areas and 154 indicators prepared on the basis of contributions from prominent experts in each of the fields of work. This article sets out the analysis methodology drawn up and possible applications are given. Results: The primary aim of the project is to provide an assessment methodology that would make it possible to optimise destination brand websites, thus providing a tool to support the work of public tourism destination managers.

  16. Methodological Considerations in Designing and Evaluating Animal-Assisted Interventions.

    Science.gov (United States)

    Stern, Cindy; Chur-Hansen, Anna

    2013-02-27

    This paper presents a discussion of the literature on animal-assisted interventions and describes limitations surrounding current methodological quality. Benefits to human physical, psychological and social health cannot be empirically confirmed due to the methodological limitations of the existing body of research, and comparisons cannot validly be made across different studies. Without a solid research base animal-assisted interventions will not receive recognition and acceptance as a credible alternative health care treatment. The paper draws on the work of four systematic reviews conducted over April-May 2009, with no date restrictions, focusing exclusively on the use of canine-assisted interventions for older people residing in long-term care. The reviews revealed a lack of good quality studies. Although the literature base has grown in volume since its inception, it predominantly consists of anecdotal accounts and reports. Experimental studies undertaken are often flawed in aspects of design, conduct and reporting. There are few qualitative studies available leading to the inability to draw definitive conclusions. It is clear that due to the complexities associated with these interventions not all weaknesses can be eliminated. However, there are basic methodological weaknesses that can be addressed in future studies in the area. Checklists for quantitative and qualitative research designs to guide future research are offered to help address methodological rigour.

  17. Evaluation of creep-fatigue life prediction methods for low-carbon/nitrogen-added SUS316

    International Nuclear Information System (INIS)

    Takahashi, Yukio

    1998-01-01

    Low-carbon/medium nitrogen 316 stainless steel called 316FR is a principal candidate for the high-temperature structural materials of a demonstration fast reactor plant. Because creep-fatigue damage is a dominant failure mechanism of the high-temperature materials subjected to thermal cycles, it is important to establish a reliable creep-fatigue life prediction method for this steel. Long-term creep tests and strain-controlled creep-fatigue tests have been conducted at various conditions for two different heats of the steel. In the constant load creep tests, both materials showed similar creep rupture strength but different ductility. The material with lower ductility exhibited shorter life under creep-fatigue loading conditions and correlation of creep-fatigue life with rupture ductility, rather than rupture strength, was made clear. Two kinds of creep-fatigue life prediction methods, i.e. time fraction rule and ductility exhaustion method were applied to predict the creep-fatigue life. Accurate description of stress relaxation behavior was achieved by an addition of 'viscous' strain to conventional creep strain and only the latter of which was assumed to contribute to creep damage in the application of ductility exhaustion method. The current version of the ductility exhaustion method was found to have very good accuracy in creep-fatigue life prediction, while the time fraction rule overpredicted creep-fatigue life as large as a factor of 30. To make a reliable estimation of the creep damage in actual components, use of ductility exhaustion method is strongly recommended. (author)

  18. Evaluation of a functional medicine approach to treating fatigue, stress, and digestive issues in women.

    Science.gov (United States)

    Cutshall, Susanne M; Bergstrom, Larry R; Kalish, Daniel J

    2016-05-01

    Fatigue, stress, and digestive disorders are common among adults, especially women. We conducted a 28-week pilot study to assess the efficacy of a functional medicine approach to improving stress, energy, fatigue, digestive issues, and quality of life in middle-aged women. Findings showed significant improvements in many stress, fatigue, and quality-of-life measures. The treatment program increased mean salivary dehydroepiandrosterone levels and the cortisol-dehydroepiandrosterone ratio. Stool sample analyses suggested that these treatments reduced Helicobacter pylori infections. This study suggests that functional medicine may be an effective approach to managing stress and gastrointestinal symptoms. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Evaluation of thiosulfate as a substitute for hydrogen sulfide in sour corrosion fatigue studies

    Science.gov (United States)

    Kappes, Mariano Alberto

    This work evaluates the possibility of replacing hydrogen sulfide (H 2S) with thiosulfate anion (S2O32- ) in sour corrosion fatigue studies. H2S increases the corrosion fatigue crack growth rate (FCGR) and can be present in carbon steel risers and flowlines used in off-shore oil production. Corrosion tests with gaseous H2S require special facilities with safety features, because H2S is a toxic and flammable gas. The possibility of replacing H2S with S2O32-, a non-toxic anion, for studying stress corrosion cracking of stainless and carbon steels in H2S solutions was first proposed by Tsujikawa et al. ( Tsujikawa et al., Corrosion, 1993. 49(5): p. 409-419). In this dissertation, Tsujikawa work will be extended to sour corrosion fatigue of carbon steels. H2S testing is often conducted in deareated condition to avoid oxygen reaction with sulfide that yields sulfur and to mimic oil production conditions. Nitrogen deareation was also adopted in S2O3 2- testing, and gas exiting the cell was forced through a sodium hydroxide trap. Measurements of the sulfide content of this trap were used to estimate the partial pressure of H2S in nitrogen, and Henry's law was used to estimate the content of H2S in the solution in the cell. H2S was produced by a redox reaction of S2O 32-, which required electrons from carbon steel corrosion. This reaction is spontaneous at the open circuit potential of steel. Therefore, H2S concentration was expected to be maximum at the steel surface, and this concentration was estimated by a mass balance analysis. Carbon steel specimens exposed to S2O32- containing solutions developed a film on their surface, composed by iron sulfide and cementite. The film was not passivating and a good conductor of electrons. Hydrogen permeation experiments proved that this film controls the rate of hydrogen absorption of steels exposed to thiosulfate containing solutions. The absorption of hydrogen in S2O3 2- solutions was compared with the absorption of hydrogen in

  20. Biologic interventions for fatigue in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Almeida, Celia; Choy, Ernest H S; Hewlett, Sarah

    2016-01-01

    BACKGROUND: Fatigue is a common and potentially distressing symptom for patients with rheumatoid arthritis (RA), with no accepted evidence-based management guidelines. Evidence suggests that biologic interventions improve symptoms and signs in RA as well as reducing joint damage. OBJECTIVES......: To evaluate the effect of biologic interventions on fatigue in rheumatoid arthritis. SEARCH METHODS: We searched the following electronic databases up to 1 April 2014: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Current Controlled Trials...... and contacted key authors. SELECTION CRITERIA: We included randomised controlled trials if they evaluated a biologic intervention in people with rheumatoid arthritis and had self reported fatigue as an outcome measure. DATA COLLECTION AND ANALYSIS: Two reviewers selected relevant trials, assessed methodological...

  1. Evaluation of local deformation behavior accompanying fatigue damage in F82H welded joint specimens by using digital image correlation

    International Nuclear Information System (INIS)

    Nakata, Toshiya; Tanigawa, Hiroyasu

    2012-01-01

    Highlights: ► In tensile, the TIG welded joint material was concentrated in the THAZ. ► In tensile, fracture occurred at the point where the axial strain converged. ► In fatigue, fracture occurred at the point where the Max. shear strain converged. ► Many macrocracks and cavities formed in the FGHAZ and THAZ of the cross section. - Abstract: By using digital image correlation, the deformation behaviors of local domains of F82H joint specimens welded using tungsten inert gas (TIG) and electron beam (EB) welding were evaluated during tensile and fatigue testing. In the tensile test specimens, the tensile strength decreased in the TIG-welded joints, and ductility decreased in both the EB- and TIG-welded joints. Because axial strain increased in the tempered heat-affected zone (HAZ) and led to the fracture of the TIG-welded joint, the strength was considered to have decreased because of welding. In fatigue testing, the number of cycles to fracture for the welded joint decreased to less than 40–60% of that for the base metal. For both fracture specimens, the largest value of shear strain was observed in the region approximately between the fine-grained HAZ and tempered HAZ; this shear strain ultimately led to fracture. Cavities and macrocracks were observed in the fine-grained HAZ and tempered HAZ in the cross sections of the fracture specimens, and geometrical damage possibly resulted in the reduction of fatigue lifetime.

  2. Multidimensional daily diary of fatigue-fibromyalgia-17 items (MDF-fibro-17): part 2 psychometric evaluation in fibromyalgia patients.

    Science.gov (United States)

    Li, Y; Morris, S; Cole, J; Dube', S; Smith, J A M; Burbridge, C; Symonds, T; Hudgens, S; Wang, W

    2017-05-18

    The Multidimensional Daily Diary of Fatigue-Fibromyalgia-17 instrument (MDF-Fibro-17) has been developed for use in fibromyalgia (FM) clinical studies and includes 5 domains: Global Fatigue Experience, Cognitive Fatigue, Physical Fatigue, Motivation, and Impact on Function. Psychometric properties of the MDF-Fibro-17 needed to demonstrate the appropriateness of using this instrument in clinical studies are presented. Psychometric analyses were conducted to evaluate the factor structure, reliability, validity, and responsiveness of the MDF-Fibro-17 using data from a Phase 2 clinical study of FM patients (N = 381). Confirmatory factor analyses (CFA) were performed to ensure understanding of the multidimensional domain structure, and a secondary factor analysis of the domains examined the appropriateness of calculating a total score in addition to domain scores. Longitudinal psychometric analyses (test-retest reliability and responder analysis) were also conducted on the data from Baseline to Week 6. The CFA supported the 17-item, 5 domain structure of this instrument as the best fit of the data: comparative fit index (CFI) and non-normed fit index (NNFI) were 0.997 and 0.992 respectively, standardized root mean square residual (SRMR) was 0.010 and the root mean square error of approximation (RMSEA) was 0.06. In addition, total score (CFI and NNFI both 0.95) met required standards. For the total and 5 domain scores, reliability and validity data were acceptable: test-retest and internal consistency were above 0.9; correlations were as expected with the Global Fatigue Index (GFI) (0.62-0.75), Fibromyalgia Impact Questionnaire (FIQ) Total (0.59-0.71), and 36-Item Short Form Health Survey (SF-36) vitality (VT) (0.43-0.53); and discrimination was shown using quintile scores for the GFI, FIQ Total, and Pain Numeric Rating Scale (NRS) quartiles. In addition, sensitivity to change was demonstrated with an overall mean responder score of -2.59 using anchor-based methods

  3. Economic evaluation studies in reproductive medicine: a systematic review of methodologic quality

    NARCIS (Netherlands)

    Moolenaar, Lobke M.; Vijgen, Sylvia M. C.; Hompes, Peter; van der Veen, Fulco; Mol, Ben Willem J.; Opmeer, Brent C.

    2013-01-01

    To evaluate the methodologic quality of economic analyses published in the field of reproductive medicine. Systematic review. Centers for reproductive care. Infertility patients. We performed a Medline search to identify economic evaluation studies in reproductive medicine. We included studies that

  4. 77 FR 26292 - Risk Evaluation and Mitigation Strategy Assessments: Social Science Methodologies to Assess Goals...

    Science.gov (United States)

    2012-05-03

    ...] Risk Evaluation and Mitigation Strategy Assessments: Social Science Methodologies to Assess Goals... announcing a public workshop entitled ``Risk Evaluation and Mitigation Strategy Assessments: Social Science... constructive dialogue and information-sharing among regulators, researchers, the pharmaceutical industry...

  5. Seismic re-evaluation of Kozloduy NPP criteria, methodology, implementation

    International Nuclear Information System (INIS)

    Kostov, M.

    2003-01-01

    The paper describes some features of the methodology applied for seismic upgrading of civil structures at the site of the Kozloduy NPP. The essence of the methodology is the use of as-build data, realistic damping and inelastic reduction factors. As an example of seismic upgrading the analyses of units 3 and 4 are presented. The analyses are showing that for effective seismic upgrading detailed investigations are needed in order to understand the significant response modes of the structures. In the presented case this is the rotation of the attached flexible structures to the stiff reactor building. Based on this an upgrading approach is applied to increase the seismic resistance for the predominant motion. The second significant approach applied is the strengthening of the prefabricated element joints. Although it is very simple it allows use of the available element capacity. (author)

  6. Evaluating a federated medical search engine: tailoring the methodology and reporting the evaluation outcomes.

    Science.gov (United States)

    Saparova, D; Belden, J; Williams, J; Richardson, B; Schuster, K

    2014-01-01

    Federated medical search engines are health information systems that provide a single access point to different types of information. Their efficiency as clinical decision support tools has been demonstrated through numerous evaluations. Despite their rigor, very few of these studies report holistic evaluations of medical search engines and even fewer base their evaluations on existing evaluation frameworks. To evaluate a federated medical search engine, MedSocket, for its potential net benefits in an established clinical setting. This study applied the Human, Organization, and Technology (HOT-fit) evaluation framework in order to evaluate MedSocket. The hierarchical structure of the HOT-factors allowed for identification of a combination of efficiency metrics. Human fit was evaluated through user satisfaction and patterns of system use; technology fit was evaluated through the measurements of time-on-task and the accuracy of the found answers; and organization fit was evaluated from the perspective of system fit to the existing organizational structure. Evaluations produced mixed results and suggested several opportunities for system improvement. On average, participants were satisfied with MedSocket searches and confident in the accuracy of retrieved answers. However, MedSocket did not meet participants' expectations in terms of download speed, access to information, and relevance of the search results. These mixed results made it necessary to conclude that in the case of MedSocket, technology fit had a significant influence on the human and organization fit. Hence, improving technological capabilities of the system is critical before its net benefits can become noticeable. The HOT-fit evaluation framework was instrumental in tailoring the methodology for conducting a comprehensive evaluation of the search engine. Such multidimensional evaluation of the search engine resulted in recommendations for system improvement.

  7. CONDOS methodology for evaluation of radiation exposure from consumer products

    International Nuclear Information System (INIS)

    O'Donnell, F.R.

    1979-01-01

    The CONDOS methodology is a tool for estimating radiation doses to man from exposures to radionuclides incorporated in consumer products. It consists of two parts: (1) an outline, checklist, and selected data for modeling the life span of a product or the material from which it is made; and (2) a computer code that uses the life-span model to calculate radiation doses to exposed individuals and population groups

  8. Evaluation of anti-fatigue and immunomodulating effects of quercetin in strenuous exercise mice

    Science.gov (United States)

    Zhang, Wei-qiang

    2017-04-01

    The purpose of the present study was to investigate the anti-fatigue and immunomodulating effects of quercetin in strenuous exercise mice. Mice were given orally either corn oil or quercetin (20, 40 and 60 mg/kg body weight suspended in corn oil) by gavage once a day for 28 day. All mice were sacrificed after rotarod test and the major biochemical parameters were analyzed in serum and liver. The results indicated that quercetin possessed anti-fatigue effects by prolonging retention times, decreasing levels of blood lactate and serum urea nitrogen, and increasing levels of blood glucose, tissue glycogen and serum glucagon. Furthermore, quercetin could improve the immune function of fatigue mice by decreasing tumor necrosis factor-α levels, and elevated interleukin-10 levels. Quercetin possessed anti-fatigue effects may be related to its immunomodulating effects.

  9. Biomechanical evaluation of an integrated fixation cage during fatigue loading: a human cadaver study.

    Science.gov (United States)

    Palepu, Vivek; Peck, Jonathan H; Simon, David D; Helgeson, Melvin D; Nagaraja, Srinidhi

    2017-04-01

    OBJECTIVE Lumbar cages with integrated fixation screws offer a low-profile alternative to a standard cage with anterior supplemental fixation. However, the mechanical stability of integrated fixation cages (IFCs) compared with a cage with anterior plate fixation under fatigue loading has not been investigated. The purpose of this study was to compare the biomechanical stability of a screw-based IFC with a standard cage coupled with that of an anterior plate under fatigue loading. METHODS Eighteen functional spinal units were implanted with either a 4-screw IFC or an anterior plate and cage (AP+C) without integrated fixation. Flexibility testing was conducted in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) on intact spines, immediately after device implantation, and post-fatigue up to 20,000 cycles of FE loading. Stability parameters such as range of motion (ROM) and lax zone (LZ) for each loading mode were compared between the 2 constructs at multiple stages of testing. In addition, construct loosening was quantified by subtracting post-instrumentation ROM from post-fatigue ROM. RESULTS IFC and AP+C configurations exhibited similar stability (ROM and LZ) at every stage of testing in FE (p ≥ 0.33) and LB (p ≥ 0.23) motions. In AR, however, IFCs had decreased ROM compared with AP+C constructs at pre-fatigue (p = 0.07) and at all post-fatigue time points (p ≤ 0.05). LZ followed a trend similar to that of ROM in AR. ROM increased toward intact motion during fatigue cycling for AP+C and IFC implants. IFC specimens remained significantly (p < 0.01) more rigid than specimens in the intact condition during fatigue for each loading mode, whereas AP+C construct motion did not differ significantly (p ≥ 0.37) in FE and LB and was significantly greater (p < 0.01) in AR motion compared with intact specimens after fatigue. Weak to moderate correlations (R 2 ≤ 56%) were observed between T-scores and construct loosening, with lower T

  10. Evaluation of taper joints with combined fatigue and crevice corrosion testing: Comparison to human explanted modular prostheses

    Energy Technology Data Exchange (ETDEWEB)

    Reclaru, L., E-mail: lucien.reclaru@pxgroup.com [PX Group S.A., Dep R and D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds (Switzerland); Brooks, R.A. [Orthopaedic Research, Addenbrooke' s Hospital, University of Cambridge, Box 180 Hills Road, CB2 0QQ Cambridge (United Kingdom); Zuberbühler, M. [Smith and Nephew Orthopaedics AG, Schachenalle 29, 5001 Aarau (Switzerland); Eschler, P.-Y.; Constantin, F. [PX Group S.A., Dep R and D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds (Switzerland); Tomoaia, G. [University of Medicine and Pharmacy Iuliu Hateganu of Cluj-Napoca, Dept. of Orthopaedics and Traumatology, Cluj-Napoca (Romania)

    2014-01-01

    The requirement for revision surgery of total joint replacements is increasing and modular joint replacement implants have been developed to provide adjustable prosthetic revision systems with improved intra-operative flexibility. An electrochemical study of the corrosion resistance of the interface between the distal and proximal modules of a modular prosthesis was performed in combination with a cyclic fatigue test. The complexity resides in the existence of interfaces between the distal part, the proximal part, and the dynamometric screw. A new technique for evaluating the resistance to cyclic dynamic corrosion with crevice stimulation was used and the method is presented. In addition, two components of the proximal module of explanted Ti6Al4V and Ti6Al7Nb prostheses were investigated by optical and electron microscopy. Our results reveal that: The electrolyte penetrates into the interface between the distal and proximal modules during cyclic dynamic fatigue tests, the distal module undergoes cracking and corrosion was generated at the interface between the two models; The comparison of the explanted proximal parts with the similar prostheses evaluated following cyclic dynamic crevice corrosion testing showed that there were significant similarities indicating that this method is suitable for evaluating materials used in the fabrication of modular prostheses. - Highlights: • Electrochemical crevice corrosion testing combined with fatigue test conducted on Ti6Al7Nb and Ti6Al4V modular prostheses • Cations released from integral prostheses • Comparison of human explanted modular prostheses with the similar prostheses evaluated in cyclic dynamic crevice corrosion.

  11. Evaluation of fatigue properties of HFIR-irradiated nimonic PE-16 at 4300C

    International Nuclear Information System (INIS)

    Grossbeck, M.L.; Liu, K.C.

    1984-01-01

    Nimonic PE-16 was irradiated in the HFIR to 6 to 9 dpa and 560 to 1000 at. ppM He at 430 0 C. Postirradiation fatigue tests revealed a reduction in fatigue life by about a factor of 10 at 430 0 C. In contrast with AISI type 316 stainless steel, no endurance limit was observed. All irradiated specimens exhibited some intergranular fracture with an increasing tendency toward cleavage like intragranular fracture for low strain ranges

  12. Fatigue evaluation including environmental effects for primary circuit components in nuclear power plants

    International Nuclear Information System (INIS)

    Seichter, Johannes; Reese, Sven H.; Klucke, Dietmar

    2013-01-01

    The influence of LWR coolant environment to the lifetime of materials in Nuclear Power Plants is in discussion internationally. Environmental phenomena were investigated in laboratory tests and published in recent years. The discussion is mainly focused both on the transition from laboratory to real plant components and on numerical calculation procedures. Since publishing of the NUREG/CR-6909 report in 2007, formulae for calculating the Fen factors have been modified several times. Various calculation procedures like the so called 'Strain-integrated Method' and 'Simplified Approach' have been published while each approach yields to different results. The recent revision of the calculation procedure, proposed by ANL in 2012, is presented and discussed with regard to possible variations in the results depending on the assumptions made. In German KTA Rules the effect of environmentally assisted fatigue (EAF) is taken into account by means of so called attention thresholds. If the threshold value is exceeded, further measures like NDT, in-service inspections including fracture mechanical evaluations or detailed assessment procedures have to be performed. One way to handle those measures is to apply sophisticated procedures and to show that the calculated CUF is below the defined attention thresholds. On the basis of a practical example, methods and approaches will be discussed and recommendations in terms of avoiding over-conservatism and misinterpretation will be presented.

  13. Fatigue evaluation including environmental effects for primary circuit components in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Seichter, Johannes [Siempelkamp Pruef- und Gutachter-Gesellschaft mbH, Dresden (Germany); Reese, Sven H.; Klucke, Dietmar [Component Technology Global Unit Generation, E.ON Kernkraft GmbH, Hannover (Germany)

    2013-05-15

    The influence of LWR coolant environment to the lifetime of materials in Nuclear Power Plants is in discussion internationally. Environmental phenomena were investigated in laboratory tests and published in recent years. The discussion is mainly focused both on the transition from laboratory to real plant components and on numerical calculation procedures. Since publishing of the NUREG/CR-6909 report in 2007, formulae for calculating the Fen factors have been modified several times. Various calculation procedures like the so called 'Strain-integrated Method' and 'Simplified Approach' have been published while each approach yields to different results. The recent revision of the calculation procedure, proposed by ANL in 2012, is presented and discussed with regard to possible variations in the results depending on the assumptions made. In German KTA Rules the effect of environmentally assisted fatigue (EAF) is taken into account by means of so called attention thresholds. If the threshold value is exceeded, further measures like NDT, in-service inspections including fracture mechanical evaluations or detailed assessment procedures have to be performed. One way to handle those measures is to apply sophisticated procedures and to show that the calculated CUF is below the defined attention thresholds. On the basis of a practical example, methods and approaches will be discussed and recommendations in terms of avoiding over-conservatism and misinterpretation will be presented.

  14. Burnout: evaluation of the efficacy and tolerability of TARGET 1® for professional fatigue syndrome (burnout).

    Science.gov (United States)

    Jacquet, Alain; Grolleau, Adeline; Jove, Jérémy; Lassalle, Régis; Moore, Nicholas

    2015-02-01

    To study the effect of a dietary supplement (TARGET 1®: a combination of casozepine, taurine, Eleutherococcus senticosus and extramel) on burnout symptomatology. A 12-week, double-blind, randomized, placebo-controlled trial was conducted in workers engaged in professional contact with patients, students or clients. All were affected by burnout syndrome based on a score of ≥4 on the Burnout Measure Scale (BMS-10). The primary outcome measure was the change in the BMS-10 score; secondary outcome measures included the change in the Maslach's Burnout Inventory scale-Human Service Survey (MBI-HSS) score and the Beck Depression Inventory. Five scores were evaluated. Eighty-seven participants were enrolled in the study: 44 received the active formulation (verum group); 43 received placebo. After 12 weeks' supplementation, the placebo group showed significant improvements in scores for BMS-10, MBI-HSS fatigue and the Beck Depression Inventory, but MBI-HSS depersonalization and task management were not improved; the verum group showed significant improvements in all five scores. The verum group consistently showed significantly greater improvements in scores than the placebo group. TARGET 1® significantly improved the symptoms of burnout after 12 weeks' use. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  15. Assessment of compliance with regulatory requirements for a best estimate methodology for evaluation of ECCS

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Un Chul; Jang, Jin Wook; Lim, Ho Gon; Jeong, Ik [Seoul National Univ., Seoul (Korea, Republic of); Sim, Suk Ku [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2000-03-15

    Best estimate methodology for evaluation of ECCS proposed by KEPCO(KREM) os using thermal-hydraulic best-estimate code and the topical report for the methodology is described that it meets the regulatory requirement of USNRC regulatory guide. In this research the assessment of compliance with regulatory guide. In this research the assessment of compliance with regulatory requirements for the methodology is performed. The state of licensing procedure of other countries and best-estimate evaluation methodologies of Europe is also investigated, The applicability of models and propriety of procedure of uncertainty analysis of KREM are appraised and compliance with USNRC regulatory guide is assessed.

  16. Investigating on the Methodology Effect when Evaluating Lucid Dream

    Directory of Open Access Journals (Sweden)

    Nicolas RIBEIRO

    2016-08-01

    Full Text Available Lucid dreaming (LD is a state of consciousness in which the dreamer is aware that he or she is dreaming and can possibly control the content of his or her dream. To investigate the LD prevalence among different samples, researchers have used different types of methodologies. With regard to retrospective self-report questionnaire, two ways of proceeding seem to emerge. In one case, a definition of LD is given to participants (During lucid dreaming, one is – while dreaming – aware of the fact that one is dreaming. It is possible to deliberately wake up, to control the dream action, or to observe passively the course of the dream with this awareness, while in the other instances, participants are presented separate questions targeting specific LD indicators (dream awareness and dream control.In the present study, we measured LD frequency in a sample of French student in order to investigate for possible disparities in LD frequency depending on the type of questionnaire as outlined above. Moreover, we also study links between the prevalence of LD as assessed respectively by each questionnaire with various factors such as Vividness of Mental Imagery and Parasomnia.Results revealed no significant difference between LD frequencies across questionnaires. For the questionnaire with definition (DefQuest, 81.05% of participants reported experience of LD once or more. Concerning the questionnaire based on LD indicators (AwarContQuest, 73.38% of participants reported having experienced LD once or more. However, with regard to the correlations analysis, links between LD prevalence and factors such as Vividness of Mental Imagery and Parasomnia, varied across questionnaires. This result is an argument suggesting that researchers should be careful when investigating links between LD and other factors. The type of methodology may influence findings on LD research. Further studies are needed to investigate on the methodology effect in LD research namely on the

  17. An Evaluative Methodology for Virtual Communities Using Web Analytics

    Science.gov (United States)

    Phippen, A. D.

    2004-01-01

    The evaluation of virtual community usage and user behaviour has its roots in social science approaches such as interview, document analysis and survey. Little evaluation is carried out using traffic or protocol analysis. Business approaches to evaluating customer/business web site usage are more advanced, in particular using advanced web…

  18. Methodology for Evaluating Safety System Operability using Virtual Parameter Network

    International Nuclear Information System (INIS)

    Park, Sukyoung; Heo, Gyunyoung; Kim, Jung Taek; Kim, Tae Wan

    2014-01-01

    KAERI (Korea Atomic Energy Research Institute) and UTK (University of Tennessee Knoxville) are working on the I-NERI project to suggest complement of this problem. This research propose the methodology which provide the alternative signal in case of unable guaranteed reliability of some instrumentation with KAERI. Proposed methodology is assumed that several instrumentations are working normally under the power supply condition because we do not consider the instrumentation survivability itself. Thus, concept of the Virtual Parameter Network (VPN) is used to identify the associations between plant parameters. This paper is extended version of the paper which was submitted last KNS meeting by changing the methodology and adding the result of the case study. In previous research, we used Artificial Neural Network (ANN) inferential technique for estimation model but every time this model showed different estimate value due to random bias each time. Therefore Auto-Associative Kernel Regression (AAKR) model which have same number of inputs and outputs is used to estimate. Also the importance measures in the previous method depend on estimation model but importance measure of improved method independent on estimation model. Also importance index of previous method depended on estimation model but importance index of improved method is independent on estimation model. In this study, we proposed the methodology to identify the internal state of power plant when severe accident happens also it has been validated through case study. SBLOCA which has large contribution to severe accident is considered as initiating event and relationship amongst parameter has been identified. VPN has ability to identify that which parameter has to be observed and which parameter can be alternative to the missing parameter when some instruments are failed in severe accident. In this study we have identified through results that commonly number 2, 3, 4 parameter has high connectivity while

  19. A methodology for evaluating ''new'' technologies in nuclear power plants

    International Nuclear Information System (INIS)

    Korsah, K.; Clark, R.L.; Holcomb, D.E.

    1994-01-01

    As obsolescence and spare parts issues drive nuclear power plants to upgrade with new technology (such as optical fiber communication systems), the ability of the new technology to withstand stressors present where it is installed needs to be determined. In particular, new standards may be required to address qualification criteria and their application to the nuclear power plants of tomorrow. This paper discusses the failure modes and age-related degradation mechanisms of fiber optic communication systems, and suggests a methodology for identifying when accelerated aging should be performed during qualification testing

  20. Methodology for Evaluating Safety System Operability using Virtual Parameter Network

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sukyoung; Heo, Gyunyoung [Kyung Hee Univ., Yongin (Korea, Republic of); Kim, Jung Taek [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Kim, Tae Wan [Kepco International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2014-05-15

    KAERI (Korea Atomic Energy Research Institute) and UTK (University of Tennessee Knoxville) are working on the I-NERI project to suggest complement of this problem. This research propose the methodology which provide the alternative signal in case of unable guaranteed reliability of some instrumentation with KAERI. Proposed methodology is assumed that several instrumentations are working normally under the power supply condition because we do not consider the instrumentation survivability itself. Thus, concept of the Virtual Parameter Network (VPN) is used to identify the associations between plant parameters. This paper is extended version of the paper which was submitted last KNS meeting by changing the methodology and adding the result of the case study. In previous research, we used Artificial Neural Network (ANN) inferential technique for estimation model but every time this model showed different estimate value due to random bias each time. Therefore Auto-Associative Kernel Regression (AAKR) model which have same number of inputs and outputs is used to estimate. Also the importance measures in the previous method depend on estimation model but importance measure of improved method independent on estimation model. Also importance index of previous method depended on estimation model but importance index of improved method is independent on estimation model. In this study, we proposed the methodology to identify the internal state of power plant when severe accident happens also it has been validated through case study. SBLOCA which has large contribution to severe accident is considered as initiating event and relationship amongst parameter has been identified. VPN has ability to identify that which parameter has to be observed and which parameter can be alternative to the missing parameter when some instruments are failed in severe accident. In this study we have identified through results that commonly number 2, 3, 4 parameter has high connectivity while

  1. Stereomicroscopic evaluation of defects caused by torsional fatigue in used hand and rotary nickel-titanium instruments.

    Science.gov (United States)

    Asthana, Geeta; Kapadwala, Marsrat I; Parmar, Girish J

    2016-01-01

    The aim of this study was to evaluate defects caused by torsional fatigue in used hand and rotary nickel-titanium (Ni-Ti) instruments by stereomicroscopic examination. One hundred five greater taper Ni-Ti instruments were used including Protaper universal hand (Dentsply Maillefer, Ballaigues, Switzerland), Protaper universal rotary (Dentsply Maillefer, Ballaigues, Switzerland), and Revo-S rotary (MicroMega, Besançon, France) files. Files were used on lower anterior teeth. After every use, the files were observed with both naked eyes and stereomicroscope at 20× magnification (Olympus, Shinjuku, Tokyo, Japan) to evaluate defects caused by torsional fatigue. Scoring was assigned to each file according to the degree of damage. The results were statistically analyzed using the Mann-Whitney U test and the Kruskal-Wallis test. A greater number of defects were seen under the stereomicroscope than on examining with naked eyes. However, the difference in methods of evaluation was not statistically significant. Revo-S files showed minimum defects, while Protaper universal hand showed maximum defects. The intergroup comparison of defects showed that the bend in Protaper universal hand instruments was statistically significant. Visible defects in Ni-Ti files due to torsional fatigue were seen by naked eyes as well as by stereomicroscope. This study emphasizes that all the files should be observed before and after every instrument cycle to minimize the risk of separation.

  2. Risk assessment methodology for evaluating releases of radioactively contaminated materials

    International Nuclear Information System (INIS)

    Chen, S.Y.

    1993-01-01

    Extensive decontamination and decommissioning (D ampersand D) activities are expected to be required in the near future in association with license termination of nuclear power facilities and cleanup efforts at the U.S. Department of Energy's (DOE's) weapons production facilities. In advance of these D ampersand D activities, it is becoming increasingly urgent that standards be established for the release of materials with residual radioactive contamination. The only standards for unrestricted release that currently exist address surface contamination. The methods used to justify those standards were developed some 20 yr ago and may not satisfy today's criteria. Furthermore, the basis of setting standards has moved away from the traditional open-quotes instrumentation-basedclose quotes concept toward a open-quotes risk-basedclose quotes approach. Therefore, as new release standards are developed, it will be necessary that risk assessment methodology consistent with modern concepts be incorporated into the process. This paper discusses recent developments in risk methodology and issues and concerns regarding the future development of standards for the release of radioactively contaminated materials

  3. An advanced revised universal slope method for low cycle fatigue evaluation of elbow piping subjected to in-plane cyclic bending displacement

    International Nuclear Information System (INIS)

    Urabe, Yoshio

    2015-01-01

    In order to rationalize the low cycle fatigue evaluation of elbow piping subjected to in-plane cyclic bending displacement, an advanced revised universal slope method is proposed. In the proposed method, the coefficient of the first term of the fatigue life equation which resembles Manson's equation is expressed by parameters of the multi-axial degree, the tensile strength and the fracture strength. Also, the coefficient of the second term is expressed by the multi-axial degree, the fracture ductility and the minimum fracture ductility under the maximum multi-axial degree. Here equivalent strain range is used for the fatigue life estimation. The previously carried out pipe elbow test data were reanalyzed using the proposed method. As the result, the experimentally obtained fatigue lives had considerably good coincidences with the predicted fatigue lives by the proposed method. Application of the proposed method is also discussed. (author)

  4. Comparison of economic evaluation methodology for the nuclear plant lifetime extension

    International Nuclear Information System (INIS)

    Song, T. H.; Jung, I. S.

    2003-01-01

    In connection with economic evaluation of NPP lifetime management, there are lots of methodologies such as present worth calculation, Levelized Unit Energy Cost (LUEC) calculation, and market benefit comparison methodology. In this paper, economic evaluation of NPP lifetime management was carried out by using these three methodologies, and the results of each was compared with the other methodologies. With these three methodologies, break even points of investment cost related to life extension of nuclear power plant were calculated. It was turned out to be as a analysis result that LUEC is more conservative than present worth calculation and that benefit comparison is more conservative than LUEC, which means that Market Benefit Comparison is the most conservative methodology, and which means base load demand of the future would be far more important than any other factors such as capacity factor, investment cost of life extension, and performance of replacing power plant

  5. High-accuracy CFD prediction methods for fluid and structure temperature fluctuations at T-junction for thermal fatigue evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Qian, Shaoxiang, E-mail: qian.shaoxiang@jgc.com [EN Technology Center, Process Technology Division, JGC Corporation, 2-3-1 Minato Mirai, Nishi-ku, Yokohama 220-6001 (Japan); Kanamaru, Shinichiro [EN Technology Center, Process Technology Division, JGC Corporation, 2-3-1 Minato Mirai, Nishi-ku, Yokohama 220-6001 (Japan); Kasahara, Naoto [Nuclear Engineering and Management, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2015-07-15

    Highlights: • Numerical methods for accurate prediction of thermal loading were proposed. • Predicted fluid temperature fluctuation (FTF) intensity is close to the experiment. • Predicted structure temperature fluctuation (STF) range is close to the experiment. • Predicted peak frequencies of FTF and STF also agree well with the experiment. • CFD results show the proposed numerical methods are of sufficiently high accuracy. - Abstract: Temperature fluctuations generated by the mixing of hot and cold fluids at a T-junction, which is widely used in nuclear power and process plants, can cause thermal fatigue failure. The conventional methods for evaluating thermal fatigue tend to provide insufficient accuracy, because they were developed based on limited experimental data and a simplified one-dimensional finite element analysis (FEA). CFD/FEA coupling analysis is expected as a useful tool for the more accurate evaluation of thermal fatigue. The present paper aims to verify the accuracy of proposed numerical methods of simulating fluid and structure temperature fluctuations at a T-junction for thermal fatigue evaluation. The dynamic Smagorinsky model (DSM) is used for large eddy simulation (LES) sub-grid scale (SGS) turbulence model, and a hybrid scheme (HS) is adopted for the calculation of convective terms in the governing equations. Also, heat transfer between fluid and structure is calculated directly through thermal conduction by creating a mesh with near wall resolution (NWR) by allocating grid points within the thermal boundary sub-layer. The simulation results show that the distribution of fluid temperature fluctuation intensity and the range of structure temperature fluctuation are remarkably close to the experimental results. Moreover, the peak frequencies of power spectrum density (PSD) of both fluid and structure temperature fluctuations also agree well with the experimental results. Therefore, the numerical methods used in the present paper are

  6. Probabilistic Material Strength Degradation Model for Inconel 718 Components Subjected to High Temperature, Mechanical Fatigue, Creep and Thermal Fatigue Effects

    Science.gov (United States)

    Bast, Callie Corinne Scheidt

    1994-01-01

    This thesis presents the on-going development of methodology for a probabilistic material strength degradation model. The probabilistic model, in the form of a postulated randomized multifactor equation, provides for quantification of uncertainty in the lifetime material strength of aerospace propulsion system components subjected to a number of diverse random effects. This model is embodied in the computer program entitled PROMISS, which can include up to eighteen different effects. Presently, the model includes four effects that typically reduce lifetime strength: high temperature, mechanical fatigue, creep, and thermal fatigue. Statistical analysis was conducted on experimental Inconel 718 data obtained from the open literature. This analysis provided regression parameters for use as the model's empirical material constants, thus calibrating the model specifically for Inconel 718. Model calibration was carried out for four variables, namely, high temperature, mechanical fatigue, creep, and thermal fatigue. Methodology to estimate standard deviations of these material constants for input into the probabilistic material strength model was developed. Using the current version of PROMISS, entitled PROMISS93, a sensitivity study for the combined effects of mechanical fatigue, creep, and thermal fatigue was performed. Results, in the form of cumulative distribution functions, illustrated the sensitivity of lifetime strength to any current value of an effect. In addition, verification studies comparing a combination of mechanical fatigue and high temperature effects by model to the combination by experiment were conducted. Thus, for Inconel 718, the basic model assumption of independence between effects was evaluated. Results from this limited verification study strongly supported this assumption.

  7. OpenKnowledge Deliverable 3.3.: A methodology for ontology matching quality evaluation

    OpenAIRE

    Yatskevich, Mikalai; Giunchiglia, Fausto; McNeill, Fiona; Shvaiko, Pavel

    2007-01-01

    This document presents an evaluation methodology for the assessment of quality results produced by ontology matchers. In particular, it discusses: (i) several standard quality measures used in the ontology matching evaluation, (ii) a methodology of how to build semiautomatically an incomplete reference alignment allowing for the assessment of quality results produced by ontology matchers and (iii) a preliminary empirical evaluation of the OpenKnowledge ontology matching component.

  8. An objective methodology for the evaluation of the air quality stations positioning

    International Nuclear Information System (INIS)

    Benassi, A.; Marson, G.; Baraldo, E.; Dalan, F.; Lorenzet, K.; Bellasio, R.; Bianconi, R.

    2006-01-01

    This work describes a methodology for the evaluation of the correct positioning of the monitoring stations of an air quality network. The methodology is based on the Italian legislation, the European Directives and on some technical documents used as guidelines at European level. The paper describes all the assumption on which the methodology is based and the results of its application to the air quality network of Region Veneto (Italy) [it

  9. Development and evaluation of an intervention aiming to reduce fatigue in airline pilots: design of a randomised controlled trial.

    Science.gov (United States)

    van Drongelen, Alwin; van der Beek, Allard J; Hlobil, Hynek; Smid, Tjabe; Boot, Cécile R L

    2013-08-26

    A considerable percentage of flight crew reports to be fatigued regularly. This is partly caused by irregular and long working hours and the crossing of time zones. It has been shown that persistent fatigue can lead to health problems, impaired performance during work, and a decreased work-private life balance. It is hypothesized that an intervention consisting of tailored advice regarding exposure to daylight, optimising sleep, physical activity, and nutrition will lead to a reduction of fatigue in airline pilots compared to a control group, which receives a minimal intervention with standard available information. The study population will consist of pilots of a large airline company. All pilots who posses a smartphone or tablet, and who are not on sick leave for more than four weeks at the moment of recruitment, will be eligible for participation.In a two-armed randomised controlled trial, participants will be allocated to an intervention group that will receive the tailored advice to optimise exposure to daylight, sleep, physical activity and nutrition, and a control group that will receive standard available information. The intervention will be applied using a smartphone application and a website, and will be tailored on flight- and participant-specific characteristics. The primary outcome of the study is perceived fatigue. Secondary outcomes are need for recovery, duration and quality of sleep, dietary and physical activity behaviours, work-private life balance, general health, and sickness absence. A process evaluation will be conducted as well. Outcomes will be measured at baseline and at three and six months after baseline. This paper describes the development of an intervention for airline pilots, consisting of tailored advice (on exposure to daylight and sleep-, physical activity, and nutrition) applied into a smartphone application. Further, the paper describes the design of the randomised controlled trial evaluating the effect of the intervention on

  10. Evaluation of shot peening on the fatigue strength of anodized Ti-6Al-4V alloy

    Directory of Open Access Journals (Sweden)

    Costa Midori Yoshikawa Pitanga

    2006-01-01

    Full Text Available The increasingly design requirements for modern engineering applications resulted in the development of new materials with improved mechanical properties. Low density, combined with excellent weight/strength ratio as well as corrosion resistance, make the titanium attractive for application in landing gears. Fatigue control is a fundamental parameter to be considered in the development of mechanical components. The aim of this research is to analyze the fatigue behavior of anodized Ti-6Al-4V alloy and the influence of shot peening pre treatment on the experimental data. Axial fatigue tests (R = 0.1 were performed, and a significant reduction in the fatigue strength of anodized Ti-6Al-4V was observed. The shot peening superficial treatment, which objective is to create a compressive residual stress field in the surface layers, showed efficiency to increase the fatigue life of anodized material. Experimental data were represented by S-N curves. Scanning electron microscopy technique (SEM was used to observe crack origin sites.

  11. Simplified Model for Evaluation of VIV-induced Fatigue Damage of Deepwater Marine Risers

    Institute of Scientific and Technical Information of China (English)

    XUE Hong-xiang; TANG Wen-yong; ZHANG Sheng-kun

    2009-01-01

    A simplified empirical model for fatigue analysis of deepwater marine risers due to vortex-induced vibration (VIV) in non-uniform current is presented. A simplified modal vibration equation is employed according to the characteristics of deepwater top tensioned risers. The response amplitude of each mode is determined by a balance between the energy feeding into the riser over the lock-in regions and the energy dissipated by the fluid damping over the remainder based on the data from self-excited oscillation and forced oscillation experiments of rigid cylinders. Multi-modal VIV fatigue loading is obtained by the square root of the sum of squares approach.Compared with previous works, this model can take fully account of the main intrinsic natures of VIV for low mass ratio structures on lock-in regions, added mass and nonlinear fluid damping. In addition, a closed form solution of fatigue damage is presented for the case of a riser with uniform mass and cross-section oscillating in a uniform flow. Fatigue analysis of a typical deepwater riser operating in Gulf of Mexico and West Africa shows that the current velocity profiles affect the riser's fatigue life significantly and the most dangerous locations of the riser are also pointed out.

  12. Evaluation of methodology for QRA in offshore operations

    International Nuclear Information System (INIS)

    Vinnem, Jan Erik

    1998-01-01

    A brief summary is presented of the development of Quantified Risk Analysis in the offshore oil and gas industry for nearly 20 years. From a modest start in Norway as a research activity, QRA has today become one of the focal points of oil and gas management in all countries around the North Sea, and also in other areas. This was mainly initiated by authority regulations and requirements, but has now for some time been driven by the industry itself, as it sees the QRA as a vehicle to gain extended flexibility with respect to optimization of offshore safety standards. This article discusses how QRAs are used, and examines in this light how methodology developments that are and should be carried out by R and D institutions and the industry. Recommendations with respect to how and where knowledge should be developed are expressed and discussed. Lastly visions for future use and developments within the QRA technology are outlined

  13. Methodology for evaluation of economic security of industrial enterprises

    OpenAIRE

    Kopytko Marta Ivanovna

    2014-01-01

    This paper investigates the features of evaluation of ensuring economic security of industrial enterprises and the algorithm of complex evaluation of the economic security of industrial enterprises over time and the system of criteria and their limit values ​​and the dynamics of change to determine the level of economic security industrial enterprise in terms of its components.

  14. A Proposed Methodology for Contextualised Evaluation in Higher Education

    Science.gov (United States)

    Nygaard, Claus; Belluigi, Dina Zoe

    2011-01-01

    This paper aims to inspire stakeholders working with quality of higher education (such as members of study boards, study programme directors, curriculum developers and teachers) to critically consider their evaluation methods in relation to a focus on student learning. We argue that many of the existing methods of evaluation in higher education…

  15. The integrated approach methodology for operator information evaluation

    International Nuclear Information System (INIS)

    Stroube, K.; Modarres, M.; Roush, M.; Hunt, N.; Pearce, R.

    1986-01-01

    The Integrated Approach has developed a complete method for evaluating the relative importance of operation information improvements. By use of decision trees the impact of information on success probability of a function or system can be evaluated. This approach couples goal trees and human success likelihoods to estimate anticipated consequences of a given information system

  16. Adapting Job Analysis Methodology to Improve Evaluation Practice

    Science.gov (United States)

    Jenkins, Susan M.; Curtin, Patrick

    2006-01-01

    This article describes how job analysis, a method commonly used in personnel research and organizational psychology, provides a systematic method for documenting program staffing and service delivery that can improve evaluators' knowledge about program operations. Job analysis data can be used to increase evaluators' insight into how staffs…

  17. [Basic principles and methodological considerations of health economic evaluations].

    Science.gov (United States)

    Loza, Cesar; Castillo-Portilla, Manuel; Rojas, José Luis; Huayanay, Leandro

    2011-01-01

    Health Economics is an essential instrument for health management, and economic evaluations can be considered as tools assisting the decision-making process for the allocation of resources in health. Currently, economic evaluations are increasingly being used worldwide, thus encouraging evidence-based decision-making and seeking efficient and rational alternatives within the framework of health services activities. In this review, we present an overview and define the basic types of economic evaluations, with emphasis on complete Economic Evaluations (EE). In addition, we review key concepts regarding the perspectives from which EE can be conducted, the types of costs that can be considered, the time horizon, discounting, assessment of uncertainty and decision rules. Finally, we describe concepts about the extrapolation and spread of economic evaluations in health.

  18. The study of evaluation methodology of the aging and degradation researches

    International Nuclear Information System (INIS)

    Cho, C. J.; Park, Z. H.; Jeong, I. S.

    2001-01-01

    To judge the usefulness of aging related researches like PLIM (Plant lifetime Management) and aging related degradation, et. al. in PSR(Periodic Safety Review), the evaluation methodology of the R and D have been proposed up to now are reviewed. The infometric methodology is considered to be the optimum method for the evaluation of the nuclear related researches. And finally, to increase the objectiveness and reliability of the infometric methodology in the aging and degradation researches, the indexes of safety, technology and economics are introduced. From this study, the infometric methodology has the advantage of the actual engineering evaluation in the nuclear related researches with other methodologies, but for the further research, the effective construction of DB and survey of various statistics in the technical reports and papers are needed

  19. Evaluation of creep-fatigue crack growth for large-scale FBR reactor vessel and NDE assessment

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young Sang; Kim, Jong Bum; Kim, Seok Hun; Yoo, Bong

    2001-03-01

    Creep fatigue crack growth contributes to the failure of FRB reactor vessels in high temperature condition. In the design stage of reactor vessel, crack growth evaluation is very important to ensure the structural safety and setup the in-service inspection strategy. In this study, creep-fatigue crack growth evaluation has been performed for the semi-elliptical surface cracks subjected to thermal loading. The thermal stress analysis of a large-scale FBR reactor vessel has been carried out for the load conditions. The distributions of axial, radial, hoop, and Von Mises stresses were obtained for the loading conditions. At the maximum point of the axial and hoop stress, the longitudinal and circumferential surface cracks (i.e. PTS crack, NDE short crack and shallow long crack) were postulated. Using the maximum and minimum values of stresses, the creep-fatigue crack growth of the proposed cracks was simulated. The crack growth rate of circumferential cracks becomes greater than that of longitudinal cracks. The total crack growth of the largest PTS crack is very small after 427 cycles. The structural integrity of a large-scale reactor can be maintained for the plant life. The crack depth growth of the shallow long crack is faster than that of the NDE short crack. In the ISI of the large-scale FBR reactor vessel, the ultrasonic inspection is beneficial to detect the shallow circumferential cracks.

  20. Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel Part II: Plate bending test and proposal of a simplified evaluation method

    Energy Technology Data Exchange (ETDEWEB)

    Ando, Masanori, E-mail: ando.masanori@jaea.go.jp; Takaya, Shigeru, E-mail: takaya.shigeru@jaea.go.jp

    2016-12-15

    Highlights: • Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel is proposed. • A simplified evaluation method is also proposed for the codification. • Both proposed evaluation method was validated by the plate bending test. • For codification, the local stress and strain behavior was analyzed. - Abstract: In the present study, to develop an evaluation procedure and design rules for Mod.9Cr-1Mo steel weld joints, a method for evaluating the creep-fatigue life of Mod.9Cr-1Mo steel weld joints was proposed based on finite element analysis (FEA) and a series of cyclic plate bending tests of longitudinal and horizontal seamed plates. The strain concentration and redistribution behaviors were evaluated and the failure cycles were estimated using FEA by considering the test conditions and metallurgical discontinuities in the weld joints. Inelastic FEA models consisting of the base metal, heat-affected zone and weld metal were employed to estimate the elastic follow-up behavior caused by the metallurgical discontinuities. The elastic follow-up factors determined by comparing the elastic and inelastic FEA results were determined to be less than 1.5. Based on the estimated elastic follow-up factors obtained via inelastic FEA, a simplified technique using elastic FEA was proposed for evaluating the creep-fatigue life in Mod.9Cr-1Mo steel weld joints. The creep-fatigue life obtained using the plate bending test was compared to those estimated from the results of inelastic FEA and by a simplified evaluation method.

  1. Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel Part II: Plate bending test and proposal of a simplified evaluation method

    International Nuclear Information System (INIS)

    Ando, Masanori; Takaya, Shigeru

    2016-01-01

    Highlights: • Creep-fatigue evaluation method for weld joint of Mod.9Cr-1Mo steel is proposed. • A simplified evaluation method is also proposed for the codification. • Both proposed evaluation method was validated by the plate bending test. • For codification, the local stress and strain behavior was analyzed. - Abstract: In the present study, to develop an evaluation procedure and design rules for Mod.9Cr-1Mo steel weld joints, a method for evaluating the creep-fatigue life of Mod.9Cr-1Mo steel weld joints was proposed based on finite element analysis (FEA) and a series of cyclic plate bending tests of longitudinal and horizontal seamed plates. The strain concentration and redistribution behaviors were evaluated and the failure cycles were estimated using FEA by considering the test conditions and metallurgical discontinuities in the weld joints. Inelastic FEA models consisting of the base metal, heat-affected zone and weld metal were employed to estimate the elastic follow-up behavior caused by the metallurgical discontinuities. The elastic follow-up factors determined by comparing the elastic and inelastic FEA results were determined to be less than 1.5. Based on the estimated elastic follow-up factors obtained via inelastic FEA, a simplified technique using elastic FEA was proposed for evaluating the creep-fatigue life in Mod.9Cr-1Mo steel weld joints. The creep-fatigue life obtained using the plate bending test was compared to those estimated from the results of inelastic FEA and by a simplified evaluation method.

  2. Nondestructive evaluation algorithm of fatigue cracks and far-side corrosion around a rivet fastener in multi-layered structures

    Energy Technology Data Exchange (ETDEWEB)

    Le, Min Hhuy; Kim, Jung Min [Research Center for IT-based Real Time NDT for Nano-Damage Tolerance, Chosun University, Gwangju (Korea, Republic of); Kim, Sejin; Wang, Dabin [Dept. of Control and Instrumentation Engineering, Graduate School, Chosun University, Gwangju (Korea, Republic of); Hwang, Young Ha [Avionics System Technology Center, KITECH, Youngcheon (Korea, Republic of)

    2016-09-15

    This research proposes a nondestructive inspection system for inspecting and localizing corrosion and fatigue cracks around rivets in air-intake structures. The system uses 64 InSb Hall sensor elements arrayed at a high spatial interval of 0.52 mm. Rivet detection and damage detection algorithms will be proposed. Analysis of the receiver operating characteristic curve and Probability of detection (POD) will be carried out to evaluate the performance of the system and detection algorithms. Artificial corrosion around a rivet with a minimum volume of 11.02 mm{sup 3} could be detected with 90/95% POD and artificial fatigue crack with minimum length of 2.95 mm from rivet body.

  3. A methodology for evaluating social impact of Environmental Education Master Training Program

    Directory of Open Access Journals (Sweden)

    Loret de Mola, E.

    2014-01-01

    Full Text Available The paper is intended to describe a methodology for evaluating social impact of Environmental Education master training program by presenting its main stages. The framework serving as starting point and other empirical methods lead to systematized and define the terms of environmental professional training, professional performance of the environmental educator, evaluation, evaluation of professional performance of environmental educators and impact evaluation; as well as distinguishing the functions of impact evaluation in the postgraduate program favoring professor, tutors and trainees development. Previously appraised by consulting experts who gave it high ranks, this methodology is currently being used in evaluating second and third editions.

  4. Evaluations of environmental effect on micro crack initiation and propagation by surface observations of fatigue specimens

    International Nuclear Information System (INIS)

    Fujikawa, Ryosuke; Abe, Shigeki; Nakamura, Takao; Kamaya, Masayuki

    2014-01-01

    Fatigue life of nuclear facilities tends to be decreased by the influence of reactor coolant, which is called environmental effect. The effect accelerates crack growth rate but the influence for crack initiation is not clarified. This study intends to discuss the environmental effect in crack initiation. The crack length and the number of cracks are measured from the investigation of fatigue test specimens in reactor coolant and air. The behavior of crack initiation is revealed from the measurement of number of cracks, crack sizes and fatigue life. From this study, environmental effect of reactor coolant is considered to influence crack initiation and increase the number of micro crack. It is also estimated that the coalescence of cracks influences the acceleration of crack growth. (author)

  5. How to Train Safe Drivers: Setting Up and Evaluating a Fatigue Training Program

    Directory of Open Access Journals (Sweden)

    Adamos Giannis

    2015-02-01

    Full Text Available Fatigue is considered as a serious risk driving behavior, causing road accidents, which in many cases involve fatalities and severe injuries. According to CARE database statistics, professional drivers are indicated as a high-risk group to be involved in a fatigue-related accident. Acknowledging these statistics, a training program on driving fatigue was organized, aiming at raising awareness of professional drivers of a leading company in building materials, in Greece. Selected experimental methods were used for collecting data before and after the training program, which allowed monitoring and assessing the potential behavioural changes. A questionnaire survey was conducted before the program implementation to 162 drivers of the company, while two months after the program, the same drivers replied to a second questionnaire. Impact assessment of the program relied on statistical analysis of the responses. Results showed the degree of penetration of the training program in the professional drivers' behavior towards safe driving.

  6. A methodology for evaluation of a markup-based specification of clinical guidelines.

    Science.gov (United States)

    Shalom, Erez; Shahar, Yuval; Taieb-Maimon, Meirav; Lunenfeld, Eitan

    2008-11-06

    We introduce a three-phase, nine-step methodology for specification of clinical guidelines (GLs) by expert physicians, clinical editors, and knowledge engineers, and for quantitative evaluation of the specification's quality. We applied this methodology to a particular framework for incremental GL structuring (mark-up) and to GLs in three clinical domains with encouraging results.

  7. A Methodology for Sustainability Evaluation and Reporting in Higher Education Institutions

    Science.gov (United States)

    Madeira, Ana C.; Carravilla, Maria Antonia; Oliveira, Jose F.; Costa, Carlos A. V.

    2011-01-01

    The purpose of this paper is to present a methodology that allows higher education institutions (HEIs) to promote, to evaluate and to report on sustainability. The ultimate goal of the afore-mentioned methodology is to help HEIs achieve sustainability. First, a model entitled Sustainability in Higher Education Institutions (SusHEI) that generally…

  8. Development and evaluation of a cancer-related fatigue patient education program: protocol of a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Görres Stefan

    2008-07-01

    Full Text Available Abstract Background Cancer-related fatigue (CRF and its impact on patients' quality of life has been an increasing subject of research. However, in Germany there is a lack of evidence-based interventions consistent with the multidimensional character of fatigue. The objective of this study is to develop and evaluate a self-management program for disease-free cancer patients to cope with CRF. Methods Based on evidence extracted from a literature review, a curriculum for the self-management program was elaborated. The curriculum was reviewed and validated by an interdisciplinary expert group and the training-modules will be pretested with a small number of participants and discussed in terms of feasibility and acceptance. To determine the efficacy of the program a randomised controlled trial will be carried out: 300 patients will be recruited from oncological practices in Bremen, Germany, and will be allocated to intervention or control group. The intervention group participates in the program, whereas the control group receives standard care and the opportunity to take part in the program after the end of the follow-up (waiting control group. Primary outcome measure is the level of fatigue, secondary outcome measures are quality of life, depression, anxiety, self-efficacy and physical activity. Data will be collected before randomisation, after intervention, and after a follow-up of 6 months. Discussion Because there are no comparable self-management programs for cancer survivors with fatigue, the development of the curriculum has been complex; therefore, the critical appraisal by the experts was an important step to validate the program and their contributions have been integrated into the curriculum. The experts appreciated the program as filling a gap in outpatient cancer care. If the results of the evaluation prove to be satisfactory, the outpatient care of cancer patients can be broadened and supplemented. Trial Registration Clinical

  9. Short time evaluation of metallic materials' fatigue potential combining destructive and non-destructive testing methods

    International Nuclear Information System (INIS)

    Starke, Peter; Wu, Haoran; Boller, Christian

    2015-01-01

    Fatigue of engineering structures is an issue from an engineering design point. The lifetime of materials being subject to repeated mechanical loads is limited. Different examples of failures and fateful air accidents have caused significant cost and claims to the operators as well as manufacturers in excess of fatalities. Criticality of failure increases with increasing age and the uncertainty of operational loads applied. In such a case a reassessment of a structural materials' condition is in big need should damage tolerance criteria still be met, being the essential ground rule for aeronautical structural design. It is therefore the challenging aim to use a metallic material's microstructure characterizing non-destructive testing (NDT) parameter or a combination of those as a parameter to be scanned over a defined surface of the component considered to more realistically characterize the damage condition and to use this information twofold: (a) to more precisely assess the structural component's residual life and (b) to feed the information recorded back into a specific database belonging to an approach named PHYBAL. The physically based fatigue life evaluation method (PHYBAL) is a short-time procedure for the evaluation of fatigue data based on a small number of fatigue tests performed on un-notched specimens only. This method significantly reduces the effort for experimentation in terms of time and cost by around 90 % and inhibits remarkable scientific as well as economic advantages. The paper highlights the high capability of PHYBAL as well as the suitability for assessing the residual life of aeronautical components also with respect to the application of this approach in the light of structural health monitoring issues.

  10. Towards Standardization of Sampling Methodology for Evaluation of ...

    African Journals Online (AJOL)

    MICHAEL

    2College of Environmental Sciences,Kaduna Polytechnic, Kaduna, Nigeria. ABSTRACT: This ... development of threshold values for risk assessment and soil quality evaluation. For the ..... Therefore the methods chosen for the different steps.

  11. Methodology for quantitative evaluation of diagnostic medical imaging

    International Nuclear Information System (INIS)

    Metz, C.

    1980-01-01

    This report deals with the evaluation of the performance of diagnostic medical imaging procedures using the Receiver Operating Characteristic or ROC analysis. The development of new tests for the statistical significance of apparent differences between ROC curves is discussed

  12. Evaluation of surgeon's muscle fatigue during thoracoscopic pulmonary lobectomy using interoperative surface electromyography.

    Science.gov (United States)

    Yoon, Seung-Hyun; Jung, Myung-Chul; Park, Seong Yong

    2016-06-01

    The aim of this study was to document the physical stress experienced by a surgeon during thoracoscopic pulmonary lobectomy and mediastinal lymph node dissection for lung cancer by measuring the intraoperative electromyography (EMG). Surface EMG was recorded during 12 cases of thoracoscopic lobectomy. During the operation, 16 channels of a wireless EMG were used to measure muscle activity and fatigue from the bilateral muscles of the splenius capitis (SC), upper trapezius (UT), middle deltoid (MD), flexor carpi radialis (FCR), extensor carpi radialis (ECR), lumbar erector spinae (LES), rectus femoralis (RF), and tibialis anterior (TA). The EMG signals were processed to collect the values of the root mean square for muscle activity and median frequency (MF) for muscle fatigue. All operations were completed without adverse events. The mean operating time was 99.16±35.15 minutes. During the operation, the mean muscle activity of all muscles was 21.91±12.85 mV. High muscle activity was observed in the bilateral FCR and ECR, whereas low muscle activity was observed in the bilateral SC and LES. The final MFs in the bilateral SC and LES were found to be decreased from the initial status, which implied increased muscle fatigue. The muscles of the right and left LES were significantly fatigued by up to 29% and 37% compared to their initial status (P=0.021 and P=0.007, respectively). The MFs of the bilateral LES decreased with time (an average decreases of 0.008/5 minutes, P=0.002 in right LES and 0.004/5 minutes, P=0.018 in left LES). During thoracoscopic lobectomy, muscle fatigue was observed in muscles related to a static posture, such as the bilateral SC, UT, and ES. Further studies are required to investigate the ergonomic adjustments needed to reduce muscle fatigue in these static muscles.

  13. On the methodology of the intercomparison of TND evaluations

    International Nuclear Information System (INIS)

    Yiftah, S.; Caner, M.; Gur, Y.

    1979-03-01

    The paper presents the problems which arise when two independent complete nuclear data evaluations of the same nuclide are available. A detailed intercomparison of the evaluations can be a multi-levelled exercise of considerable detail, the stages of which cannot always be performed. However, a detailed intercomparison can be a rich source for improving considerably the nuclear data used for the different applications. Preliminary examples of intercomparison are given for illustrative purpose. (B.G.)

  14. Methodology for GPS Synchronization Evaluation with High Accuracy

    OpenAIRE

    Li Zan; Braun Torsten; Dimitrova Desislava

    2015-01-01

    Clock synchronization in the order of nanoseconds is one of the critical factors for time based localization. Currently used time synchronization methods are developed for the more relaxed needs of network operation. Their usability for positioning should be carefully evaluated. In this paper we are particularly interested in GPS based time synchronization. To judge its usability for localization we need a method that can evaluate the achieved time synchronization with nanosecond accuracy. Ou...

  15. Methodology for GPS Synchronization Evaluation with High Accuracy

    OpenAIRE

    Li, Zan; Braun, Torsten; Dimitrova, Desislava Cvetanova

    2015-01-01

    Clock synchronization in the order of nanoseconds is one of the critical factors for time-based localization. Currently used time synchronization methods are developed for the more relaxed needs of network operation. Their usability for positioning should be carefully evaluated. In this paper, we are particularly interested in GPS-based time synchronization. To judge its usability for localization we need a method that can evaluate the achieved time synchronization with nanosecond accuracy. O...

  16. Experimental evaluation of the fretting fatigue behavior of high-strength steel monostrands

    DEFF Research Database (Denmark)

    Winkler, Jan; Fischer, Gregor; Georgakis, Christos T.

    2013-01-01

    In this paper, the fretting fatigue behavior of pretensioned high-strength steel monostrands is investigated. A method based on the digital image correlation (DIC) technique was used to quantify the relative movement between individual wires along the length of the monostrand. The experimental data....... Moreover, the paper provides relevant information about the monostrand bending stiffness and the extent of relative displacement between core and outer wires of the monostrand undergoing flexural deformations. The results presented herein are of special interest for the fatigue analysis of modern stay...

  17. Projecting labor demand and worker immigration at nuclear power plant construction sites: an evaluation of methodology

    International Nuclear Information System (INIS)

    Herzog, H.W. Jr; Schlottmann, A.M.; Schriver, W.R.

    1981-12-01

    The study evaluates methodology employed for the projection of labor demand at, and worker migration to, nuclear power plant construction sites. In addition, suggestions are offered as to how this projection methodology might be improved. The study focuses on projection methodologies which forecast either construction worker migration or labor requirements of alternative types of construction activity. Suggested methodological improvements relate both to institutional factors within the nuclear power plant construction industry, and to a better use of craft-specific data on construction worker demand/supply. In addition, the timeliness and availability of the regional occupational data required to support, or implement these suggestions are examined

  18. Automating the evaluation of flood damages: methodology and potential gains

    Science.gov (United States)

    Eleutério, Julian; Martinez, Edgar Daniel

    2010-05-01

    The evaluation of flood damage potential consists of three main steps: assessing and processing data, combining data and calculating potential damages. The first step consists of modelling hazard and assessing vulnerability. In general, this step of the evaluation demands more time and investments than the others. The second step of the evaluation consists of combining spatial data on hazard with spatial data on vulnerability. Geographic Information System (GIS) is a fundamental tool in the realization of this step. GIS software allows the simultaneous analysis of spatial and matrix data. The third step of the evaluation consists of calculating potential damages by means of damage-functions or contingent analysis. All steps demand time and expertise. However, the last two steps must be realized several times when comparing different management scenarios. In addition, uncertainty analysis and sensitivity test are made during the second and third steps of the evaluation. The feasibility of these steps could be relevant in the choice of the extent of the evaluation. Low feasibility could lead to choosing not to evaluate uncertainty or to limit the number of scenario comparisons. Several computer models have been developed over time in order to evaluate the flood risk. GIS software is largely used to realise flood risk analysis. The software is used to combine and process different types of data, and to visualise the risk and the evaluation results. The main advantages of using a GIS in these analyses are: the possibility of "easily" realising the analyses several times, in order to compare different scenarios and study uncertainty; the generation of datasets which could be used any time in future to support territorial decision making; the possibility of adding information over time to update the dataset and make other analyses. However, these analyses require personnel specialisation and time. The use of GIS software to evaluate the flood risk requires personnel with

  19. Aging evaluation methodology of periodic safety review in Korea

    International Nuclear Information System (INIS)

    Park, Heung-Bae; Jung, Sung-Gyu; Jin, Tae-Eun; Jeong, Ill-Seok

    2002-01-01

    In Korea plant lifetime management (PLIM) study for Kori Unit 1 has been performed since 1993. Meanwhile, periodic safety review (PSR) for all operating nuclear power plants (NPPs) has been started with Kori Unit 1 since 2000 per IAEA recommendation. The evaluation period is 10 years, and safety (evaluation) factors are 11 per IAEA guidelines as represented in table 1. The relationship between PSR factors and PLIM is also represented. Among these factors evaluation of 'management of aging' is one of the most important and difficult factor. This factor is related to 'actual condition of the NPP', 'use of experience from other nuclear NPPs and of research findings', and 'management of aging'. The object of 'management of aging' is to obtain plant safety through identifying actual condition of system, structure and components (SSCs) and evaluating aging phenomena and residual life of SSCs using operating experience and research findings. The paper describes the scope and procedure of valuation of 'management of aging', such as, screening criteria of SSCs, Code and Standards, evaluation of SSCs and safety issues as represented. Evaluating SSCs are determined using final safety analysis report (FSAR) and power unit maintenance system for Nuclear Ver. III (PUMAS/N-III). The screening criteria of SSCs are safety-related items (quality class Q), safety-impact items (quality class T), backfitting rule items (fire protection (10CFR50.48), environmental qualification (10CFR50.49), pressurized thermal shock (10CFR50.61), anticipated transient without scram (10CFR50.62), and station blackout (10CFR50.63)) and regulating authority requiring items[1∼3]. The purpose of review of Code and Standards is identifying actual condition of the NPP and evaluating aging management using effective Code and Standards corresponding to reactor facilities. Code and Standards is composed of regulating laws, FSAR items, administrative actions, regulating actions, agreement items, and other

  20. Improvement of test methodology for evaluating diesel fuel stability

    Energy Technology Data Exchange (ETDEWEB)

    Gutman, M.; Tartakovsky, L.; Kirzhner, Y.; Zvirin, Y. [Internal Combustion Engines Lab., Haifa (Israel); Luria, D. [Fuel Authority, Tel Aviv (Israel); Weiss, A.; Shuftan, M. [Israel Defence Forces, Tel Aviv (Israel)

    1995-05-01

    The storage stability of diesel fuel has been extensively investigated for many years under laboratory conditions. Although continuous efforts have been made to improve testing techniques, there does not yet exist a generally accepted correlation between laboratory methods (such as chemical analysis of the fuel) and actual diesel engine tests. A testing method was developed by the Technion Internal Combustion Engines Laboratory (TICEL), in order to address this problem. The test procedure was designed to simulate diesel engine operation under field conditions. It is based on running a laboratory-modified single cylinder diesel engine for 50 h under cycling operating conditions. The overall rating of each test is based on individual evaluation of the deposits and residue formation in the fuel filter, nozzle body and needle, piston head, piston rings, exhaust valve, and combustion chamber (six parameters). Two methods for analyzing the test results were used: objective, based on measured data, and subjective, based on visual evaluation results of these deposits by a group of experts. Only the residual level in the fuel filter was evaluated quantitatively by measured results. In order to achieve higher accuracy of the method, the test procedure was improved by introducing the measured results of nozzle fouling as an additional objective evaluating (seventh) parameter. This factor is evaluated on the basis of the change in the air flow rate through the nozzle before and after the complete engine test. Other improvements in the method include the use of the nozzle assembly photograph in the test evaluation, and representation of all seven parameters on a continuous scale instead of the discrete scale used anteriorly, in order to achieve higher accuracy. This paper also contains the results obtained by application of this improved fuel stability test for a diesel fuel stored for a five-year period.

  1. A Proposed Methodology for Contextualised Evaluation in Higher Education

    DEFF Research Database (Denmark)

    Nygaard, Claus; Belluigi, Dian Zoe

    2011-01-01

    This paper aims to inspire stakeholders working with quality of higher education (such as members of study boards, study programme directors, curriculum developers and teachers) to critically consider their evaluation methods in relation to a focus on student learning. We argue that many...... of the existing methods of evaluation in higher education are underpinned by a conception of learning that is de‐contextualised. As a consequence, many data collection methods do not address aspects that affect students’ learning. This is problematic because the core aim of higher education is to facilitate...

  2. Supporting the Future Total Force: A Methodology for Evaluating Potential Air National Guard Mission Assignments

    National Research Council Canada - National Science Library

    Lynch, Kristin F; Drew, John G; Sleeper, Sally; Williams, William A; Masters, James M; Luangkesorn, Louis; Tripp, Robert S; Lichter, Dahlia S; Roll, Charles R

    2007-01-01

    ... trained, highly experienced personnel with no aircraft to operate and support. The authors develop a methodology to evaluate missions that could be transferred from the active component to the ANG without significant cost to the total force...

  3. Economic evaluations of occupational health interventions from a corporate perspective - A systematic review of methodological quality

    NARCIS (Netherlands)

    Uegaki, K.; Bruijne, M.C. de; Lambeek, L.; Anema, J.R.; Beek, A.J. van der; Mechelen, W. van; Tulder, M.W. van

    2010-01-01

    Objective: Using a standardized quality criteria list, we appraised the methodological quality of economic evaluations of occupational safety and health (OSH) interventions conducted from a corporate perspective. Methods: The primary literature search was conducted in Medline and Embase.

  4. Evaluating environmental policy instruments mixes; a methodology illustrated by noise policy in the Netherlands

    NARCIS (Netherlands)

    Weber, Miriam; Driessen, Peter P J; Runhaar, Hens A C

    2014-01-01

    Environmental policy is characterised by complexity, in causes and effects, resulting in various combinations of policy instruments. However, evaluating these policy instrument mixes and assessing their effectiveness is difficult because of a lack of methodological approaches. This paper therefore

  5. Monuments deterioration evaluation, using digited images. A methodology

    Directory of Open Access Journals (Sweden)

    Ángel, María C.

    1995-12-01

    Full Text Available In this work a methodology is proposed for data processing, integrating the techniques of digital images processing and the analytical capacity of graphical referencing systems and relational databases, in relation with the monuments. The images are generated using the digital image processing and they are included into a graphical data processing systems associated with a database containing the characteristics of the ashars or constituent elements. By combination of the images with the database induced properties the information is processed. The results are thematic maps that we save such as images. These maps are layers of new information (deduced levels. The elaboration of these maps allows attacking the problems of the restoration, renovation or treatment of the different monumental spaces on a global way, paying special attention on the most gravely affected areas.

    En este trabajo se propone una metodología para el tratamiento de la información, integrando las técnicas de proceso digital de imágenes, la capacidad de análisis de los sistemas de referenciación gráfica y las bases de datos relacionales, referidas a monumentos. Para ello se elaboran las imágenes base por algoritmos propios del proceso digital, incluyendo aquellas en una aplicación especifica que asocia cada capa a una base de datos con las propiedades petrofísicas, hídricas, etc., o bien entre si, dando lugar a mapas temáticos. La generación de estos mapas permite abordar los problemas de restauración, rehabilitación o tratamiento de los diferentes espacios monumentales de forma global, con incidencia especial en las zonas más afectadas.

  6. Situated Research Design and Methodological Choices in Formative Program Evaluation

    Science.gov (United States)

    Supovitz, Jonathan

    2013-01-01

    Design-based implementation research offers the opportunity to rethink the relationships between intervention, research, and situation to better attune research and evaluation to the program development process. Using a heuristic called the intervention development curve, I describe the rough trajectory that programs typically follow as they…

  7. Methodology for Evaluating Quality and Reusability of Learning Objects

    Science.gov (United States)

    Kurilovas, Eugenijus; Bireniene, Virginija; Serikoviene, Silvija

    2011-01-01

    The aim of the paper is to present the scientific model and several methods for the expert evaluation of quality of learning objects (LOs) paying especial attention to LOs reusability level. The activities of eQNet Quality Network for a European Learning Resource Exchange (LRE) aimed to improve reusability of LOs of European Schoolnet's LRE…

  8. Evaluation of two radiographic developers by Sensitometric methodology

    International Nuclear Information System (INIS)

    Alcantara, T.M.C.

    1976-01-01

    The results obtained by processing Eastman KODAK's Periapical ultra speed film in a solution primarily suggested for use in automatic processors are evaluated though the characteristic curve. The solution tested (Tiplimatic) was employed at 30 0 C during 30 seconds. The activity of this solution was also studied, during 80 days. (M.A.C.) [pt

  9. Absorbed dose evaluations in retrospective dosimetry: Methodological developments using quartz

    DEFF Research Database (Denmark)

    Bailiff, I.K.; Bøtter-Jensen, L.; Correcher, V.

    2000-01-01

    Dose evaluation procedures based on luminescence techniques were applied to 50 quartz samples extracted from bricks that had been obtained from populated or partly populated settlements in Russia and Ukraine downwind of the Chernobyl NPP. Determinations of accrued dose in the range similar to 30...

  10. A usage-centered evaluation methodology for unmanned ground vehicles

    NARCIS (Netherlands)

    Diggelen, J. van; Looije, R.; Mioch, T.; Neerincx, M.A.; Smets, N.J.J.M.

    2012-01-01

    This paper presents a usage-centered evaluation method to assess the capabilities of a particular Unmanned Ground Vehicle (UGV) for establishing the operational goals. The method includes a test battery consisting of basic tasks (e.g., slalom, funnel driving, object detection). Tests can be of

  11. Methodological proposal for environmental impact evaluation since different specific methods

    International Nuclear Information System (INIS)

    Leon Pelaez, Juan Diego; Lopera Arango Gabriel Jaime

    1999-01-01

    Some conceptual and practical elements related to environmental impact evaluation are described and related to the preparation of technical reports (environmental impact studies and environmental management plans) to be presented to environmental authorities for obtaining the environmental permits for development projects. In the first part of the document a summary of the main aspects of normative type is made that support the studies of environmental impact in Colombia. We propose a diagram for boarding and elaboration of the evaluation of environmental impact, which begins with the description of the project and of the environmental conditions in the area of the same. Passing then to identify the impacts through a method matricial and continuing with the quantitative evaluation of the same. For which we propose the use of the method developed by Arboleda (1994). Also we propose to qualify the activities of the project and the components of the environment in their relative importance, by means of a method here denominated agglomerate evaluation. Which allows finding those activities more impacting and the mostly impacted components. Lastly it is presented some models for the elaboration and presentation of the environmental management plans. The pursuit programs and those of environmental supervision

  12. New Methodologies To Evaluate the Memory Strategies of Deaf Individuals.

    Science.gov (United States)

    Clark, Diane

    Prior studies have often confounded linguistic and perceptual performance when evaluating deaf subjects' skills, a confusion that may be responsible for results indicating lesser recall ability among the deaf. In this series of studies this linguistic/perceptual confound was investigated in both the iconic and short term memory of deaf…

  13. Comparison of economic evaluation methodology between levelized method and the evaluation system in China

    International Nuclear Information System (INIS)

    Zhang Shengli

    2005-01-01

    Different methodology would bring different results. This paper includes an introduction of levelized discounted generation cost methodology as well as that of Chinese system, respectively. In general, there have two key indices in Chinese evaluation system, they are generation cost and electricity sales price to the grid. This paper contains a description of cost breakdown and calculation procedure for each index. Comparison between these two methods and the primary differences are also included. For the first time, equations for calculating generation cost and selling price to the grid based on Chinese system have been derived, and its accuracy has been shown through running the special computer program. The two systems are quite different in many aspects. Firstly, levelized generation cost is always calculated with discounted method that excluded in Chinese system. Secondly, levelized generation cost is a single and constant value that would not change over the economic life while generation cost in Chinese system is estimated on a year by year base. Thirdly, the makeup of generation cost in Chinese system is different from that of levelized system since taxes and dividend share removed. Finally, the electricity sales price in Chinese system is more similar to levelized generation cost. (authors)

  14. Status of the Gen-IV Proliferation Resistance and Physical Protection (PRPP) Evaluation Methodology

    International Nuclear Information System (INIS)

    Whitlock, J.; Bari, R.; Peterson, P.; Padoani, F.; Cojazzi, G.G.M.; Renda, G.; ); Cazalet, J.; Haas, E.; Hori, K.; Kawakubo, Y.; Chang, S.; Kim, H.; Kwon, E.-H.; Yoo, H.; Chebeskov, A.; Pshakin, G.; Pilat, J.F.; Therios, I.; Bertel, E.

    2015-01-01

    Methodologies have been developed within the Generation IV International Forum (GIF) to support the assessment and improvement of system performance in the areas safeguards, security, economics and safety. Of these four areas, safeguards and security are the subjects of the GIF working group on Proliferation Resistance and Physical Protection (PRPP). Since the PRPP methodology (now at Revision 6) represents a mature, generic, and comprehensive evaluation approach, and is freely available on the GIF public website, several non-GIF technical groups have chosen to utilize the PRPP methodology for their own goals. Indeed, the results of the evaluations performed with the methodology are intended for three types of generic users: system designers, programme policy makers, and external stakeholders. The PRPP Working Group developed the methodology through a series of demonstration and case studies. In addition, over the past few years various national and international groups have applied the methodology to inform nuclear energy system designs, as well as to support the development of approaches to advanced safeguards. A number of international workshops have also been held which have introduced the methodology to design groups and other stakeholders. In this paper we summarize the technical progress and accomplishments of the PRPP evaluation methodology, including applications outside GIF, and we outline the PRPP methodology's relationship with the IAEA's INPRO methodology. Current challenges with the efficient implementation of the methodology are outlined, along with our path forward for increasing its accessibility to a broader stakeholder audience - including supporting the next generation of skilled professionals in the nuclear non-proliferation field. (author)

  15. A Fuzzy-Based Fusion Method of Multimodal Sensor-Based Measurements for the Quantitative Evaluation of Eye Fatigue on 3D Displays

    Directory of Open Access Journals (Sweden)

    Jae Won Bang

    2015-05-01

    Full Text Available With the rapid increase of 3-dimensional (3D content, considerable research related to the 3D human factor has been undertaken for quantitatively evaluating visual discomfort, including eye fatigue and dizziness, caused by viewing 3D content. Various modalities such as electroencephalograms (EEGs, biomedical signals, and eye responses have been investigated. However, the majority of the previous research has analyzed each modality separately to measure user eye fatigue. This cannot guarantee the credibility of the resulting eye fatigue evaluations. Therefore, we propose a new method for quantitatively evaluating eye fatigue related to 3D content by combining multimodal measurements. This research is novel for the following four reasons: first, for the evaluation of eye fatigue with high credibility on 3D displays, a fuzzy-based fusion method (FBFM is proposed based on the multimodalities of EEG signals, eye blinking rate (BR, facial temperature (FT, and subjective evaluation (SE; second, to measure a more accurate variation of eye fatigue (before and after watching a 3D display, we obtain the quality scores of EEG signals, eye BR, FT and SE; third, for combining the values of the four modalities we obtain the optimal weights of the EEG signals BR, FT and SE using a fuzzy system based on quality scores; fourth, the quantitative level of the variation of eye fatigue is finally obtained using the weighted sum of the values measured by the four modalities. Experimental results confirm that the effectiveness of the proposed FBFM is greater than other conventional multimodal measurements. Moreover, the credibility of the variations of the eye fatigue using the FBFM before and after watching the 3D display is proven using a t-test and descriptive statistical analysis using effect size.

  16. Experimental evaluation on the influence of autoclave sterilization on the cyclic fatigue of new nickel-titanium rotary instruments.

    Science.gov (United States)

    Plotino, Gianluca; Costanzo, Alberto; Grande, Nicola M; Petrovic, Renata; Testarelli, Luca; Gambarini, Gianluca

    2012-02-01

    The purpose of this study was to evaluate the effect of autoclave sterilization on cyclic fatigue resistance of rotary endodontic instruments made of traditional and new nickel-titanium (NiTi) alloys. Four NiTi rotary endodontic instruments of the same size (tip diameter 0.40 mm and constant .04 taper) were selected: K3, Mtwo, Vortex, and K3 XF prototypes. Each group was then divided into 2 subgroups, unsterilized instruments and sterilized instruments. The sterilized instruments were subjected to 10 cycles of autoclave sterilization. Twelve files from each different subgroup were tested for cyclic fatigue resistance. Means and standard deviations of number of cycles to failure (NCF) and fragment length of the fractured tip were calculated for each group, and data were statistically analyzed (P instruments for each type of file, differences were statistically significant (P instruments did not show significant differences (P > .05) in the mean NCF as a result of sterilization cycles (K3, 424 versus 439 NCF; Mtwo, 409 versus 419 NCF; Vortex, 454 versus 480 NCF). Comparing the results among the different groups, K3 XF (either sterilized or not) showed a mean NCF significantly higher than all other files (P endodontic instruments except for the K3 XF prototypes of rotary instruments that demonstrated a significant increase of cyclic fatigue resistance. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  17. EVALUATION OF TRAINING AND‐METHODOLOGICAL SUPPORT OF UNIVERSITY COURSES (in Russian

    Directory of Open Access Journals (Sweden)

    Natalia BELKINA

    2012-04-01

    Full Text Available Quality of teaching at a Higher Education Institution certainly depends on the integrity and quality of its training and methodological support. However, in order to improve this quality it is necessary to have a sound methodology for evaluation of such support. This article contains a list of recommended university teaching course materials, criteria of their separate components evaluation and an approach to calculating the quality levels of separate components and teaching course materials as a whole.

  18. Are marketed topical metronidazole creams bioequivalent? Evaluation by in vivo microdialysis sampling and tape stripping methodology

    DEFF Research Database (Denmark)

    Garcia Ortiz, Patricia Elodia; Hansen, S H; Shah, Surendra P.

    2011-01-01

    To evaluate the bioequivalence of 3 marketed topical metronidazole formulations by simultaneous dermal microdialysis and stratum corneum sampling by the tape stripping methodology, and to compare the techniques as tools for the determination of bioequivalence.......To evaluate the bioequivalence of 3 marketed topical metronidazole formulations by simultaneous dermal microdialysis and stratum corneum sampling by the tape stripping methodology, and to compare the techniques as tools for the determination of bioequivalence....

  19. Evaluation of notch effects in low cycle fatigue of alloy 718 using critical distances

    Directory of Open Access Journals (Sweden)

    Eriksson Robert

    2018-01-01

    Full Text Available Gas turbine disks contain many notch-like features acting as stress raisers. The fatigue life based on the notch root stress may be overly conservative as the steep stress gradient in front of the notch may give rise to so-called notch support. In the current work, the theory of critical distances was applied to the prediction of the total fatigue life of low cycle fatigued, notched specimens made from alloy 718. The fatigue tests were performed at 450 °C and 550 °C. It was found that, for lives shorter than 5000–10000 cycles, the notched specimens had longer lives than would have been expected based on the notch root strain. For lives longer than 5000–10000 cycles, there were no notch support. The life prediction for notched specimens could be significantly improved by basing the prediction on the strain chosen some distance from the notch (the critical distance. An expression for calculating the critical distance based on the notch root strain was suggested.

  20. Probabilistic evaluation of fatigue crack growth in SA 508 and SA 533 B steel

    International Nuclear Information System (INIS)

    Dufresne, J.; Rieunier, J.B.

    1982-07-01

    This paper describes the method used to select the best representative law of fatigue crack growth in view of its introduction in a probabilist computer code). A modelling of the selected law (Paris law) and the statistical distribution of the corresponding numerical coefficients are presented. Results of computation are given in the case of a PWR pressure vessel with defects in belt line weld

  1. A structural strain method for low-cycle fatigue evaluation of welded components

    International Nuclear Information System (INIS)

    Dong, P.; Pei, X.; Xing, S.; Kim, M.H.

    2014-01-01

    In this paper, a new structural strain method is presented to extend the early structural stress based master S–N curve method to low cycle fatigue regime in which plastic deformation can be significant while an elastic core is still present. The method is formulated by taking advantage of elastically calculated mesh-insensitive structural stresses based on nodal forces available from finite element solutions. The structural strain definition is consistent with classical plate and shell theory in which a linear through-thickness deformation field is assumed a priori in both elastic or elastic–plastic regimes. With considerations of both yield and equilibrium conditions, the resulting structural strains are analytically solved if assuming elastic and perfectly plastic material behavior. The formulation can be readily extended to strain-hardening materials for which structural strains can be numerically calculated with ease. The method is shown effective in correlating low-cycle fatigue test data of various sources documented in the literature into a single narrow scatter band which is remarkable consistent with the scatter band of the existing master S–N curve adopted ASME B and PV Code since 2007. With this new method, some of the inconsistencies of the pseudo-elastic structural stress procedure in 2007 ASME Div 2 Code can now be eliminated, such as its use of Neuber's rule in approximating structural strain beyond yield. More importantly, both low cycle and high cycle fatigue behaviors can now be treated in a unified manner. The earlier mesh-insensitive structural stress based master S–N curve method can now be viewed as an application of the structural strain method in high cycle regime, in which structural strains are linearly related to traction-based structural stresses according to Hooke's law. In low-cycle regime, the structural strain method characterizes fatigue damage directly in terms of structural strains that satisfy linear through

  2. METAHEURISTICS EVALUATION: A PROPOSAL FOR A MULTICRITERIA METHODOLOGY

    Directory of Open Access Journals (Sweden)

    Valdir Agustinho de Melo

    2015-12-01

    Full Text Available ABSTRACT In this work we propose a multicriteria evaluation scheme for heuristic algorithms based on the classic Condorcet ranking technique. Weights are associated to the ranking of an algorithm among a set being object of comparison. We used five criteria and a function on the set of natural numbers to create a ranking. The discussed comparison involves three well-known problems of combinatorial optimization - Traveling Salesperson Problem (TSP, Capacitated Vehicle Routing Problem (CVRP and Quadratic Assignment Problem (QAP. The tested instances came from public libraries. Each algorithm was used with essentially the same structure, the same local search was applied and the initial solutions were similarly built. It is important to note that the work does not make proposals involving algorithms: the results for the three problems are shown only to illustrate the operation of the evaluation technique. Four metaheuristics - GRASP, Tabu Search, ILS and VNS - are therefore only used for the comparisons.

  3. Evaluation of Adult Literacy Education in the United States: A Review of Methodological Issues

    Science.gov (United States)

    Shi, Yan; Tsang, Mun C.

    2008-01-01

    This is a critical review of methodological issues in the evaluation of adult literacy education programs in the United States. It addresses the key research questions: What are the appropriate methods for evaluating these programs under given circumstances. It identifies 15 evaluation studies that are representative of a range of adult literacy…

  4. The methodological quality of economic evaluation studies in obstetrics and gynecology: a systematic review

    NARCIS (Netherlands)

    Vijgen, Sylvia M. C.; Opmeer, Brent C.; Mol, Ben Willem J.

    2013-01-01

    We evaluated the methodological quality of economic evaluation studies in the field of obstetrics and gynecology published in the last decade. A MEDLINE search was performed to find economic evaluation studies in obstetrics and gynecology from the years 1997 through 2009. We included full economic

  5. Mechanism analysis and evaluation methodology of regenerative braking contribution to energy efficiency improvement of electrified vehicles

    International Nuclear Information System (INIS)

    Lv, Chen; Zhang, Junzhi; Li, Yutong; Yuan, Ye

    2015-01-01

    Highlights: • The energy flow of an electric vehicle with regenerative brake is analyzed. • Methodology for measuring the regen brake contribution is discussed. • Evaluation parameters of regen brake contribution are proposed. • Vehicle tests are carried out on chassis dynamometer. • Test results verify the evaluation method and parameters proposed. - Abstract: This article discusses the mechanism and evaluation methods of contribution brought by regenerative braking to electric vehicle’s energy efficiency improvement. The energy flow of an electric vehicle considering the braking energy regeneration was analyzed. Then, methodologies for measuring the contribution made by regenerative brake to vehicle energy efficiency improvement were introduced. Based on the energy flow analyzed, two different evaluation parameters were proposed. Vehicle tests were carried out on chassis dynamometer under typical driving cycles with three different control strategies. The experimental results the difference between the proposed two evaluation parameters, and demonstrated the feasibility and effectiveness of the evaluation methodologies proposed

  6. Review of methodologies and polices for evaluation of energy efficiency in high energy-consuming industry

    International Nuclear Information System (INIS)

    Li, Ming-Jia; Tao, Wen-Quan

    2017-01-01

    Highlights: • The classification of the industrial energy efficiency index has been summarized. • The factors of energy efficiency and their implement in industries are discussed. • Four main evaluation methodologies of energy efficiency in industries are concluded. • Utilization of the methodologies in energy efficiency evaluations are illustrated. • Related polices and suggestions based on energy efficiency evaluations are provided. - Abstract: Energy efficiency of high energy-consuming industries plays a significant role in social sustainability, economic performance and environmental protection of any nation. In order to evaluate the energy efficiency and guide the sustainability development, various methodologies have been proposed for energy demand management and to measure the energy efficiency performance accurately in the past decades. A systematical review of these methodologies are conducted in the present paper. First, the classification of the industrial energy efficiency index has been summarized to track the previous application studies. The single measurement indicator and the composite index benchmarking are highly recognized as the modeling tools for power industries and policy-making in worldwide countries. They are the pivotal figures to convey the fundamental information in energy systems for improving the performance in fields such as economy, environment and technology. Second, the six factors that influence the energy efficiency in industry are discussed. Third, four major evaluation methodologies of energy efficiency are explained in detail, including stochastic frontier analysis, data envelopment analysis, exergy analysis and benchmarking comparison. The basic models and the developments of these methodologies are introduced. The recent utilization of these methodologies in the energy efficiency evaluations are illustrated. Some drawbacks of these methodologies are also discussed. Other related methods or influential indicators

  7. Evaluation of the Effect of Surface Finish on High-Cycle Fatigue of SLM-IN718

    Science.gov (United States)

    Lambert, D. M.

    2016-01-01

    The surface finish of parts produced by additive manufacturing processes is much rougher than the surface finish generated by machining processes, and a rougher surface can reduce the fatigue strength of a part. This paper discusses an effort to quantify that reduction of strength in high-cycle fatigue for selective laser melt (SLM) coupons. A high-cycle fatigue (HCF) knockdown factor was estimated for Inconel 718, manufactured with the SLM process. This factor is the percentage reduction from the maximum stress in fatigue for low-stress ground (LSG) specimens to the maximum stress of those left with the original surface condition at the same fatigue life. Specimens were provided by a number of vendors, free to use their "best practice"; only one heat treat condition was considered; and several test temperatures were characterized, including room temperature, 800F, 1000F, and 1200F. The 1000F data had a large variance, and was omitted from consideration in this document. A first method used linear approximations extracted from the graphs, and only where data was available for both. A recommended knockdown factor of the as-built surface condition (average roughness of approximately 245 micro-inches/inch) versus low-stress ground condition (roughness no more than 4 micro-inches/inch) was established at approximately 1/3 or 33%. This is to say that for the as-built surface condition, a maximum stress of 2/3 of the stress for LSG can be expected to produce a similar life in the as-built surface condition. In this first evaluation, the knockdown factor did not appear to be a function of temperature. A second approach, the "KP method", incorporated the surface finish measure into a new parameter termed the pseudo-stress intensity factor, Kp, which was formulated to be similar to the fracture mechanics stress intensity factor. Using Kp, the variance seemed to be reduced across all sources, and knockdown factors were estimated using Kp over the range where data occurred. A

  8. Interim report on nodel evaluation methodology and the evaluation of LEAP

    Energy Technology Data Exchange (ETDEWEB)

    Alsmiller, R.G. Jr.; Barish, J.; Bjornstad, D.

    1980-04-01

    This report describes progress made at ORNL toward development and demonstration of a methodology for evaluating energy-economic modeling codes and important results derived from these codes. To bolster traditional evaluation methods with more-quantitative procedures of interest to the Energy Information Administration, ORNL is applying sensitivity theory as part of a comprehensive effort to quantify the importance of various data and model parameters to the key results that are of interest. The Long-Term Energy Analysis Program (LEAP) was chosen as the initial focus for the research. LEAP is an energy-economy model which resides in the Long-Term Energy Analysis Division (LTEAD) of the Integrative Analysis Group in the Office of Applied Analysis, EIA. LTEAD developed Model 22C of LEAP for two reasons: (1) to prepare projections through the year 2020, which were needed for the 1978 EIA Annual Report to Congress and (2) to develop a base for analyses of specific options for Federal action. LEAP Model 22C and its uses are described to provide the background for this interim description of the model evaluation effort at ORNL. 19 figures, 10 tables.

  9. Prospective evaluation of the prevalence and severity of fatigue in patients with prostate cancer undergoing radical external beam radiotherapy and neoadjuvant hormone therapy.

    Science.gov (United States)

    Truong, Pauline T; Berthelet, Eric; Lee, Junella C; Petersen, Ross; Lim, Jan T W; Gaul, Catherine A; Pai, Howard; Blood, Paul; Ludgate, Charles M

    2006-06-01

    To prospectively evaluate the prevalence and severity of fatigue and its impact on quality of life (QOL) during and after radical external beam radiotherapy (RT) for prostate cancer. Twenty-eight men with prostate cancer undergoing RT over 6-8 consecutive weeks were prospectively accrued. The Brief Fatigue Inventory (BFI), a validated fatigue assessment tool, was administered at five time points: baseline (week 1), middle of RT (week 3-4), end of RT (last week of RT), and follow-up (median 6.5 weeks after RT). The BFI contained nine questions, each using 0-10 ratings to quantify fatigue severity and interference with six QOL domains. The prevalence of moderate-severe fatigue was plotted as a function of time. Mean sum and subscale scores at each time point were compared to baseline scores using Wilcoxon tests. Linear regression analyses were performed to assess associations between fatigue scores and age, tumor and treatment characteristics. The median age was 69 years (range 57-84), Gleason score 7 (range 6-10), and presenting PSA 9.0 ng/mL (range 2.5 ng/mL-103.0 ng/mL). Patients were treated once daily to a median dose of 74 Gy (range 60 Gy-78 Gy) over a median of 37 fractions (range 30-39). Hormone therapy was used in all patients (median duration 12.2 months). The prevalence of moderate-severe present fatigue increased from 7% at baseline to 8% at mid-RT and 32% at RT completion. Compared to baseline (mean score 11.5), fatigue increased significantly mid-RT (mean score 14.6, p = 0.03) and peaked at the end of RT (mean score 23.5, p = 0.001). Fatigue significantly interfered with walking ability, normal work, daily chores, and enjoyment of life only at the end of RT. After RT completion, fatigue improved but remained higher compared to baseline at 6.5 weeks of follow-up (mean score 15.0, p = 0.02). On linear regression analysis, age, Gleason score, PSA, T-stage, hormone therapy duration, RT dose and fractions were not significantly associated with mean fatigue

  10. The development of evaluation methodology for advanced interactive communication

    International Nuclear Information System (INIS)

    Okamoto, K.

    2005-01-01

    Face-to-face communication is one of the essential style of communication. Trough face-to-face communication, people exchange much information at a time, both verbal and non-verbal information, which is most effective to learn each other. The authors focused on the face-to-face communication, and developed an evaluation method to quantify the effectiveness of communication. We regard conversation as an exchange of keywords. The effectiveness of conversation is valued by the amount of the keywords, and the achievement of mutual understandings. Through two people's face-to-face communication, the author quantified the shared information by measuring the change of the amount of the participants' knowledge. The participants' knowledge is counted by the words they can give. We measured the change in their shared knowledge (number of the words they gave associated to the theme). And we also quantified the discords in their understandings against their partners by measuring the discords between the knowledge that they think they share and the knowledge that they really share. Through these data, we evaluate the effectiveness of communication and analyzed the trends of mutual understanding. (authors)

  11. Evaluation methodology and prospective introduction scenarios of FR cycle systems

    International Nuclear Information System (INIS)

    Fujii, Sumio; Katoh, Atsushi; Sato, Kazujiro

    2003-01-01

    The 21st century society will be facing growing demand of energy, global environmental issues and concerns about fossil fuel exhaustion. In this society, it is essential to seek for a sustainable energy system to solve these energy-related concerns. In order to find ways for solving these problems, 'Feasibility Study on Commercialized FR Cycle System' was launched in 1999 as a joint research project of JNC, electric utilities, JAERI, CRIEPI etc. This project aims to build promising FR cycle technologies for the 21st century. Now, we are in the second phase (JFY 2001-2005) of this project. At the end of the second phase, we will propose promising concepts through applying innovative technologies. We started this Feasibility Study with defining the development target, which ended in five items; safety, economy, environmental burden, resource utilization and nuclear non-proliferation. These items should also serve as basic viewpoints to evaluate achievements of the study. This paper describes how we evaluate FR cycle options to come up with the final promising candidates. This paper also describes a prospective scenario to introduce FR cycle system, which shows how the FR cycle will be replacing existing LWRs by using limited natural uranium resource and spent fuels. (author)

  12. Development of CANDU ECCS performance evaluation methodology and guides

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Kwang Hyun; Park, Kyung Soo; Chu, Won Ho [Korea Maritime Univ., Jinhae (Korea, Republic of)

    2003-03-15

    The objectives of the present work are to carry out technical evaluation and review of CANDU safety analysis methods in order to assist development of performance evaluation methods and review guides for CANDU ECCS. The applicability of PWR ECCS analysis models are examined and it suggests that unique data or models for CANDU are required for the following phenomena: break characteristics and flow, frictional pressure drop, post-CHF heat transfer correlations, core flow distribution during blowdown, containment pressure, and reflux rate. For safety analysis of CANDU, conservative analysis or best estimate analysis can be used. The main advantage of BE analysis is a more realistic prediction of margins to acceptance criteria. The expectation is that margins demonstrated with BE methods would be larger that when a conservative approach is applied. Some outstanding safety analysis issues can be resolved by demonstration that accident consequences are more benign than previously predicted. Success criteria for analysis and review of Large LOCA can be developed by top-down approach. The highest-level success criteria can be extracted from C-6 and from them, the lower level criteria can be developed step-by-step, in a logical fashion. The overall objectives for analysis and review are to verify radiological consequences and frequency are met.

  13. Process evaluation of a tailored mobile health intervention aiming to reduce fatigue in airline pilots

    Directory of Open Access Journals (Sweden)

    Alwin van Drongelen

    2016-08-01

    Full Text Available Abstract Background MORE Energy is a mobile health intervention which aims to reduce fatigue and improve health in airline pilots. The primary objective of this process evaluation was to assess the reach, dose delivered, compliance, fidelity, barriers and facilitators, and satisfaction of the intervention. The second objective was to investigate the associations of adherence to the intervention with compliance and with participant satisfaction. Thirdly, we investigated differences between the subgroups within the target population. Methods The intervention consisted of a smartphone application, supported by a website. It provided advice on optimal light exposure, sleep, nutrition, and physical activity, tailored to flight and personal characteristics. The reach of the intervention was determined by comparing the intervention group participants and the airline pilots who did not participate. The dose delivered was defined as the total number of participants that was sent an instruction email. Objective compliance was measured through the Control Management System of the application. To determine the fidelity, an extensive log was kept throughout the intervention period. Subjective compliance, satisfaction, barriers, facilitators, and adherence were assessed using online questionnaires. Associations between the extent to which the participants applied the advice in daily life (adherence, compliance, and satisfaction were analysed as well. Finally, outcomes of participants of different age groups and haul types were compared. Results A total of 2222 pilots were made aware of the study. From this group, 502 pilots met the inclusion criteria and did agree to participate. The reach of the study proved to be 22 % and the dose delivered was 99 %. The included pilots were randomized into the intervention group (n = 251 or the control group (n = 251. Of the intervention group participants, 81 % consulted any advice, while 17 % did this during

  14. Process evaluation of a tailored mobile health intervention aiming to reduce fatigue in airline pilots.

    Science.gov (United States)

    van Drongelen, Alwin; Boot, Cécile R L; Hlobil, Hynek; Smid, Tjabe; van der Beek, Allard J

    2016-08-26

    MORE Energy is a mobile health intervention which aims to reduce fatigue and improve health in airline pilots. The primary objective of this process evaluation was to assess the reach, dose delivered, compliance, fidelity, barriers and facilitators, and satisfaction of the intervention. The second objective was to investigate the associations of adherence to the intervention with compliance and with participant satisfaction. Thirdly, we investigated differences between the subgroups within the target population. The intervention consisted of a smartphone application, supported by a website. It provided advice on optimal light exposure, sleep, nutrition, and physical activity, tailored to flight and personal characteristics. The reach of the intervention was determined by comparing the intervention group participants and the airline pilots who did not participate. The dose delivered was defined as the total number of participants that was sent an instruction email. Objective compliance was measured through the Control Management System of the application. To determine the fidelity, an extensive log was kept throughout the intervention period. Subjective compliance, satisfaction, barriers, facilitators, and adherence were assessed using online questionnaires. Associations between the extent to which the participants applied the advice in daily life (adherence), compliance, and satisfaction were analysed as well. Finally, outcomes of participants of different age groups and haul types were compared. A total of 2222 pilots were made aware of the study. From this group, 502 pilots met the inclusion criteria and did agree to participate. The reach of the study proved to be 22 % and the dose delivered was 99 %. The included pilots were randomized into the intervention group (n = 251) or the control group (n = 251). Of the intervention group participants, 81 % consulted any advice, while 17 % did this during four weeks or more. Fidelity was 67 %. The

  15. Methodology evaluation of innovative projects under risk and uncertainty

    Directory of Open Access Journals (Sweden)

    2012-09-01

    Full Text Available This article deals with problems connected with the assessment of innovative projects in the context of risk and uncertainty, topical issues of evaluation of innovative projects at the present stage of development of the Russian economy. By the example of the solution of the "crossing the river" is considering the possibility of using hierarchical models to address it. In what follows, and compares the priorities of different groups of factors are given by calculating the overall costs and benefits. The paper provides a rationale for combined use of four aspects: the beneficial aspects of the decision (the benefits and opportunities and negative (costs and risks that may lead to the decision in question.

  16. Using Bioacoustical Methodologies to Evaluate Equine Hearing Capabilities and Cognition

    Science.gov (United States)

    Makepeace, Shawn

    The field of Bioacoustics is an emerging field of science that investigates various aspects of animal audiology and communication. More recently, audiological means have been used to evaluate the cognitive abilities of animals using event related brain potentials (ERP's). The Mismatch Negativity (MMN) component of the ERP is considered a cognitive neuroelectric phenomenon since it is generated in the area of the cortex that is responsible for evaluating sound stimuli including the ability to discriminate. Such discrimination produces a negative-going waveform with a relative latency of about 150-250 msec when elicited with auditory stimuli in human adults. The MMN response is elicited by use of the oddball paradigm in which two different tones are presented in pseudo-random order. The purpose of this study was to determine if elicitation of the MMN is achievable in the horse by use of current equipment in a non-clinical setting such as a barn. During the course of this experiment, it became obvious that the major challenge was the excessive amount of noise that inundated the waveforms thereby making any specific waves even remotely discernible. Attempts were made to improve the signal-to-noise ratio (SNR) by modifications to the testing unit and the addition of several in-line and digital filters. However, even with these modifications, the MMN response still could not be identifiable within the noise of the waveforms. Therefore, the matter of whether or not the horse elicits a MMN response should be revised to if it is even feasible to elicit a MMN response in these animals.

  17. Evaluation methodology of a manipulator actuator for the dismantling process during nuclear decommissioning

    International Nuclear Information System (INIS)

    Park, Jongwon; Kim, Chang-Hoi; Jeong, Kyung-min; Choi, Byung-Seon; Moon, Jeikwon

    2016-01-01

    Highlights: • A methodology to evaluate actuators of a dismantling manipulator. • Evaluation criteria for choosing the most suitable actuator type. • A mathematical evaluation model for evaluation. • The evaluation method is expected to be used for determining other manipulators. - Abstract: This paper presents a methodology to evaluate actuators of a manipulator for dismantling nuclear power plants. Actuators are the most dominant components because a dismantling manipulator relies heavily on the actuator type used. To select the most suitable actuator, evaluation criteria are presented in four categories based on the nuclear dismantling environment. A mathematical model is presented and evaluation results are calculated with weights and scores for each criterion. The proposed evaluation method is expected to be used for determining other aspects of the design of dismantling manipulators.

  18. Development of a methodology to evaluate material accountability in pyroprocess

    Science.gov (United States)

    Woo, Seungmin

    sampling calculated by the central limit theorem and the Geary-Hinkley transformation. Then, the uncertainty propagation through the key-pyroprocess is conducted to analyze the Material Unaccounted For (MUF), which is a random variable defined as a receipt minus a shipment of a process, in the system. The random variable, LOPu, is defined for evaluating the non-detection probability at each Key Measurement Point (KMP) as the original Pu mass minus the Pu mass after a missing scenario. A number of assemblies for the LOPu to be 8 kg is considered in this calculation. The probability of detection for the 8 kg LOPu is evaluated with respect the size of granule and powder using the event tree analysis and the hypothesis testing method. We can observe there are possible cases showing the probability of detection for the 8 kg LOPu less than 95%. In order to enhance the detection rate, a new Material Balance Area (MBA) model is defined for the key-pyroprocess. The probabilities of detection for all spent fuel types based on the new MBA model are greater than 99%. Furthermore, it is observed that the probability of detection significantly increases by increasing granule sample sizes to evaluate the Pu-to-244Cm-ratio before the key-pyroprocess. Based on these observations, even though the Pu material accountability in pyroprocess is affected by the non-uniformity of nuclide composition when the Pu-to-244Cm-ratio method is being applied, that is surmounted by decreasing the uncertainty of measured ratio by increasing sample sizes and modifying the MBAs and KMPs. (Abstract shortened by ProQuest.).

  19. A Pragmatic Evaluation of the National Cancer Institute Physician Data Query (PDQ)®-Based Brief Counseling on Cancer-Related Fatigue among Patients Undergoing Radiation Therapy

    Science.gov (United States)

    Bauml, Joshua; Xie, Sharon X; Penn, Courtney; Desai, Krupali; Dong, Kimberly W; Bruner, Deborah Watkins; Vapiwala, Neha; Mao, Jun James

    2018-01-01

    Purpose Cancer-Related Fatigue (CRF) negatively affects quality of life among cancer patients. This study seeks to evaluate the outcome and patient receptiveness of a brief counseling program based on National Cancer Institute (NCI) PDQ® information to manage CRF when integrated into Radiation Therapy (RT). Methods We conducted a prospective cohort study among patients undergoing non-palliative RT. Patients with stage I–III tumors and with Karnofsky score 60 or better were given a ten-minute behavioral counseling session during the first two weeks of RT. The Brief Fatigue Inventory (BFI) was administered at baseline/end of RT. Results Of 93 patients enrolled, 89% found the counseling useful and practical. By the end of RT, 59% reported increased exercise, 41.6% sought nutrition counseling, 72.7% prioritized daily activities, 74.4% took daytime naps, and 70.5% talked with other cancer patients. Regarding counseling, patients who had received chemotherapy prior to RT had no change in fatigue (−0.2), those who received RT alone had mild increase in fatigue (0.7, p=0.02), and those who received concurrent chemotherapy experienced a substantial increase in fatigue (3.0 to 5.2, p=0.05). Higher baseline fatigue and receipt of chemotherapy were predictive of worsened fatigue in a multivariate model (both p<0.01). Conclusion Our data suggests that brief behavioral counseling based on NCI guidelines is well accepted by patients showing an uptake in many activities to cope with CRF. Those who receive concurrent chemotherapy and with higher baseline fatigue are at risk for worsening fatigue despite of guideline-based therapy. PMID:29479490

  20. BWR power oscillation evaluation methodologies in core design

    International Nuclear Information System (INIS)

    Hotta, Akitoshi

    1995-01-01

    At the initial stage of BWR development, the power oscillation due to the nuclear-thermal interaction originated in random boiling phenomena and nuclear void feedback was feared. But it was shown that under the high pressure condition in the normal operation of recent commercial BWRs, the core is in very stable state. However, power oscillation events have been observed in actual machines, and it is necessary to do the stability evaluation that sufficiently reflects the detailed operation conditions of actual plants. As the cause of power oscillation events, the instability of control system and nuclear-thermal coupling instability are important, and their mechanisms are explained. As the model for analyzing the stability of BWR core, the nuclear-thermal coupling model in frequency domain is the central existence. As the information for the design, the parameters of fuel assemblies, and the nuclear parameters and the thermohydraulic parameters of cores are enumerated. LAPUR-TSI is a nuclear-thermal coupling model. The analysis system in the software of Tokyo Electric Power Co. is outlined, and the analysis model was verified. (K.I.)

  1. Time-dependent methodology for fault tree evaluation

    International Nuclear Information System (INIS)

    Vesely, W.B.

    1976-01-01

    Any fault tree may be evaluated applying the method called the kinetic theory of fault trees. The basic feature of this method as presented here is in that any information on primary failure, type failure or peak failure is derived from three characteristics: probability of existence, failure intensity and failure density. The determination of the said three characteristics for a given phenomenon yields the remaining probabilistic information on the individual aspects of the failure and on their totality for the whole observed period. The probabilistic characteristics are determined by applying the analysis of phenomenon probability. The total time dependent information on the peak failure is obtained by using the type failures (critical paths) of the fault tree. By applying the said process the total time dependent information is obtained for every primary failure and type failure of the fault tree. In the application of the method of the kinetic theory of fault trees represented by the PREP and KITT programmes, the type failures are first obtained using the deterministic testing method or using the Monte Carlo simulation (PREP programme). The respective characteristics are then determined using the kinetic theory of fault trees (KITT programmes). (Oy)

  2. Methodology for surge pressure evaluation in a water injection system

    Energy Technology Data Exchange (ETDEWEB)

    Meliande, Patricia; Nascimento, Elson A. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. de Engenharia Civil; Mascarenhas, Flavio C.B. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Lab. de Hidraulica Computacional; Dandoulakis, Joao P. [SHELL of Brazil, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    Predicting transient effects, known as surge pressures, is of high importance for offshore industry. It involves detailed computer modeling that attempts to simulate the complex interaction between flow line and fluid in order to ensure efficient system integrity. Platform process operators normally raise concerns whether the water injection system is adequately designed or not to be protected against possible surge pressures during sudden valve closure. This report aims to evaluate the surge pressures in Bijupira and Salema water injection systems due to valve closure, through a computer model simulation. Comparisons among the results from empirical formulations are discussed and supplementary analysis for Salema system were performed in order to define the maximum volumetric flow rate for which the design pressure was able to withstand. Maximum surge pressure values of 287.76 bar and 318.58 bar, obtained in Salema and Bijupira respectively, using empirical formulations have surpassed the operating pressure design, while the computer model results have pointed the greatest surge pressure value of 282 bar in Salema system. (author)

  3. Evaluating health effects of transport interventions methodologic case study.

    Science.gov (United States)

    Ogilvie, David; Mitchell, Richard; Mutrie, Nanette; Petticrew, Mark; Platt, Stephen

    2006-08-01

    There is little evidence about the effects of environmental interventions on population levels of physical activity. Major transport projects may promote or discourage physical activity in the form of walking and cycling, but researching the health effects of such "natural experiments" in transport policy or infrastructure is challenging. Case study of attempts in 2004-2005 to evaluate the effects of two major transport projects in Scotland: an urban congestion charging scheme in Edinburgh, and a new urban motorway (freeway) in Glasgow. These interventions are typical of many major transport projects. They are unique to their context. They cannot easily be separated from the other components of the wider policies within which they occur. When, where, and how they are implemented are political decisions over which researchers have no control. Baseline data collection required for longitudinal studies may need to be planned before the intervention is certain to take place. There is no simple way of defining a population or area exposed to the intervention or of defining control groups. Changes in quantitative measures of health-related behavior may be difficult to detect. Major transport projects have clear potential to influence population health, but it is difficult to define the interventions, categorize exposure, or measure outcomes in ways that are likely to be seen as credible in the field of public health intervention research. A final study design is proposed in which multiple methods and spatial levels of analysis are combined in a longitudinal quasi-experimental study.

  4. A methodology to emulate and evaluate a productive virtual workstation

    Science.gov (United States)

    Krubsack, David; Haberman, David

    1992-01-01

    The Advanced Display and Computer Augmented Control (ADCACS) Program at ACT is sponsored by NASA Ames to investigate the broad field of technologies which must be combined to design a 'virtual' workstation for the Space Station Freedom. This program is progressing in several areas and resulted in the definition of requirements for a workstation. A unique combination of technologies at the ACT Laboratory have been networked to effectively create an experimental environment. This experimental environment allows the integration of nonconventional input devices with a high power graphics engine within the framework of an expert system shell which coordinates the heterogeneous inputs with the 'virtual' presentation. The flexibility of the workstation is evolved as experiments are designed and conducted to evaluate the condition descriptions and rule sets of the expert system shell and its effectiveness in driving the graphics engine. Workstation productivity has been defined by the achievable performance in the emulator of the calibrated 'sensitivity' of input devices, the graphics presentation, the possible optical enhancements to achieve a wide field of view color image and the flexibility of conditional descriptions in the expert system shell in adapting to prototype problems.

  5. Evaluation of validity and reliability of a methodology for measuring human postural attitude and its relation to temporomandibular joint disorders

    Science.gov (United States)

    Fernández, Ramón Fuentes; Carter, Pablo; Muñoz, Sergio; Silva, Héctor; Venegas, Gonzalo Hernán Oporto; Cantin, Mario; Ottone, Nicolás Ernesto

    2016-01-01

    INTRODUCTION Temporomandibular joint disorders (TMJDs) are caused by several factors such as anatomical, neuromuscular and psychological alterations. A relationship has been established between TMJDs and postural alterations, a type of anatomical alteration. An anterior position of the head requires hyperactivity of the posterior neck region and shoulder muscles to prevent the head from falling forward. This compensatory muscular function may cause fatigue, discomfort and trigger point activation. To our knowledge, a method for assessing human postural attitude in more than one plane has not been reported. Thus, the aim of this study was to design a methodology to measure the external human postural attitude in frontal and sagittal planes, with proper validity and reliability analyses. METHODS The variable postures of 78 subjects (36 men, 42 women; age 18–24 years) were evaluated. The postural attitudes of the subjects were measured in the frontal and sagittal planes, using an acromiopelvimeter, grid panel and Fox plane. RESULTS The method we designed for measuring postural attitudes had adequate reliability and validity, both qualitatively and quantitatively, based on Cohen’s Kappa coefficient (> 0.87) and Pearson’s correlation coefficient (r = 0.824, > 80%). CONCLUSION This method exhibits adequate metrical properties and can therefore be used in further research on the association of human body posture with skeletal types and TMJDs. PMID:26768173

  6. Adrenal Fatigue

    Science.gov (United States)

    ... Search Featured Resource New Mobile App DOWNLOAD Adrenal Fatigue October 2017 Download PDFs English Editors Irina Bancos, MD Additional Resources Mayo Clinic What is adrenal fatigue? The term “adrenal fatigue” has been used to ...

  7. Comparisons of ASME-code fatigue-evaluation methods for nuclear Class 1 piping with Class 2 or 3 piping

    International Nuclear Information System (INIS)

    Rodabaugh, E.C.

    1983-06-01

    The fatigue evaluation procedure used in the ASME Boiler and Pressure Vessel Code, Sect. III, Nuclear Power Plant Components, for Class 1 piping is different from the procedure used for Class 2 or 3 piping. The basis for each procedure is described, and correlations between the two procedures are presented. Conditions under which either procedure or both may be unconservative are noted. Potential changes in the Class 2 or 3 piping procedure to explicitly cover all loadings are discussed. However, the report is intended to be informative, and while the contents of the report may guide future Code changes, specific recommendations are not given herein

  8. A ductility exhaustion evaluation of some long term creep/fatigue tests on austenitic steel

    International Nuclear Information System (INIS)

    Wood, D.S.; Wynn, J.; Austin, C.; Green, J.G.

    1988-01-01

    A limited number of long term creep/fatigue tests performed on two batches of Type 316 steel and one batch of associated 17Cr8Ni2Mo weld metal are reported. Test durations range from 5000 to 32,000 h and temperatures from 550 to 625 0 C. Subsequent metallographic examination shows the failures to be wholly or predominantly intergranular. The results are analysed using a ductility exhaustion approach and it is shown that the endurances obtained are within a factor of two of predicted values. The results confirm that the design approach to creep/fatigue currently being developed in the U.K. and based on ductility exhaustion is likely to be satisfactory. (author)

  9. Evaluation of weldment creep and fatigue strength-reduction factors for elevated-temperature design

    International Nuclear Information System (INIS)

    Corum, J.M.

    1989-01-01

    New explicit weldment strength criteria in the form of creep and fatigue strength-reduction factors were recently introduced into the American Society of Mechanical Engineers Code Case N-47, which governs the design of elevated-temperature nuclear plants components in the United States. This paper provides some of the background and logic for these factors and their use, and it describes the results of a series of long-term, confirmatory, creep-rupture and fatigue tests of simple welded structures. The structures (welded plates and tubes) were made of 316 stainless steel base metal and 16-8-2 weld filler metal. Overall, the results provide further substantiation of the validity of the strength-reduction factor approach for ensuring adequate life in elevated-temperature nuclear component weldments. 16 refs., 7 figs

  10. Evaluation of creep-fatigue strength of P122 high temperature boiler material

    International Nuclear Information System (INIS)

    Pumwa, John

    2003-01-01

    In components, which operate at high temperatures, changes in conditions at the beginning and end of operation or during operation result in transient temperature gradients. If these transients are repeated, the differential thermal expansion during each transient may result in thermally induced cyclic stresses. The extent of the resulting fatigue damage depends on the nature and frequency of the transient, the thermal gradient in the component, and the material properties. Components, which are subjected to thermally induced stresses generally, operate within the creep range so that damage due to both fatigue and creep has to be taken into account. In order to select the correct materials for these hostile operating environmental conditions, it is vitally important to understand the behaviour of mechanical properties such as creep-fatigue properties of these materials. This paper reports the results of standard creep-fatigue tests conducted using P122 (HCM12A or 12Cr-1.8W-1.5Cu) high temperature boiler material. P122 is one of the latest developed materials for high temperature environments, which has the potential to be successful in such hostile operation environments. The tests were conducted at temperatures ranging from 550degC to 700degC at 50degC intervals with strain ranges of ±1.5 to ±3.0% at 0.5% intervals and a strain rate of 4 x 10 -3 s -1 with an application of 10-minute tensile hold time using a closed-loop hydraulic Instron material testing machine with a servo hydraulic controller. The results confirm that P122 is comparable to conventional high temperature steels. (author)

  11. Evaluation of Creep-Fatigue Damage in 304 Stainless Steel using Ultrasonic Non-Destructive Test

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Sik [Safetech Co. Ltd., Kimhae (Korea, Republic of); Oh, Yong Jun [Hanbat National Univ., Daejon (Korea, Republic of); Nam, Soo Woo [KISTI ReSEAT Program, Seoul (Korea, Republic of)

    2011-12-15

    It is well known that grain boundary cavitation is the main failure mechanism in austenitic stainless steel under tensile hold creep-fatigue interaction conditions. The cavities are nucleated at the grain boundary during cyclic loading and grow to become grain boundary cracks. The attenuation of ultrasound depends on scattering and absorption in polycrystalline materials. Scattering occurs when a propagation wave encounters microstructural discontinuities, such as internal voids or cavities. Since the density of the creepfatigue cavities increases with the fatigue cycles, the attenuation of ultrasound will also be increased with the fatigue cycles and this attenuation can be detected nondestructively. In this study, it is found that individual grain boundary cavities are formed and grow up to about 100 cycles and then, these cavities coalesce to become cracks. The measured ultrasonic attenuation increased with the cycles up to cycle 100, where it reached a maximum value and then decreased with further cycles. These experimental measurements strongly indicate that the open pores of cavities contribute to the attenuation of ultrasonic waves. However, when the cavities develop, at the grain boundary cracks whose crack surfaces are in contact with each other, there is no longer any open space and the ultrasonic wave may propagate across the cracks. Therefore, the attenuation of ultrasonic waves will be decreased. This phenomenon of maximum attenuation is very important to judge the stage of grain boundary crack development, which is the indication of the dangerous stage of the structures.

  12. Evaluation of fatigue damage induced by thermal striping in a T junction using the three dimensional coupling method and frequency response method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Hye; Choi, Jae boong; Kim, Moon Ki [Sungkyunkwan Univ., Seoul (Korea, Republic of); Huh, Nam Su [Seoul Nat' l Univ., Seoul (Korea, Republic of); Lee, Jin Ho [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2012-10-15

    Thermal fatigue cracking induced by thermal stratification, cycling and striping have been observed in several PWR plants. Especially, thermal striping, the highly fluctuating thermal layer, became one of the significant problems, since it can cause un predicted high cycle thermal fatigue (HCTF) at piping systems. This problem are usually found in T junctions of energy cooling systems, where cold and hot flows with high level of turbulence mix together. Thermal striping can cause the networks of fatigue crack at the vicinity of weld parts and these cracks can propagate to significant depth in a relatively short time. Therefore, thermal striping and fatigue crack initiations should be predicted in advance to prevent the severe failure of piping systems. The final goal of this research is to develop a rational thermal and mechanical model considering thermohydraulic characteristics of thermal striping and an evaluation procedure to predict the initiation of thermal fatigue crack. As a first step, we evaluated the fatigue damage in a T junction using two widely used methods. Then, we analyzed the results of each method and conducted comparisons and verifications.

  13. Performance Evaluation and Measurement of the Organization in Strategic Analysis and Control: Methodological Aspects

    OpenAIRE

    Živan Ristić; Neđo Balaban

    2006-01-01

    Information acquired by measuring and evaluation are a necessary condition for good decision-making in strategic management. This work deals with : (a) Methodological aspects of evaluation (kinds of evaluation, metaevaluation) and measurement (supposition of isomorphism in measurement, kinds and levels of measurement, errors in measurement and the basic characteristics of measurement) (b) Evaluation and measurement of potential and accomplishments of the organization in Kaplan-Norton perspect...

  14. Development of a methodology of evaluation of financial stability of commercial banks

    Directory of Open Access Journals (Sweden)

    Brauers Willem Karel M.

    2014-01-01

    Full Text Available The field of evaluation of financial stability of commercial banks, which emanates from persistent existence of financial crisis, induces interest of researchers for over a century. The span of prevailing methodologies stretches from over-simplified risk-return approaches to ones comprising large number of economic variables on the micro- and/or macro-economic level. Methodologies of rating agencies and current methodologies reviewed and applied by the ECB are not intended for reducing information asymmetry in the market of commercial banks. In the paper it is shown that the Lithuanian financial system is bankbased with deposits of households being its primary sources, and its stability is primarily depending on behavior of depositors. A methodology of evaluation of commercial banks with features of decreasing information asymmetry in the market of commercial banks is being developed by comparing different MCDA methods.

  15. The status of proliferation resistance evaluation methodology development in GEN IV international forum

    International Nuclear Information System (INIS)

    Inoue, Naoko; Kawakubo, Yoko; Seya, Michio; Suzuki, Mitsutoshi; Kuno, Yusuke; Senzaki, Masao

    2010-01-01

    The Generation IV Nuclear Energy Systems International Forum (GIF) Proliferation Resistance and Physical Protection Working Group (PR and PP WG) was established in December 2002 in order to develop the PR and PP evaluation methodology for GEN IV nuclear energy systems. The methodology has been studied and established by international consensus. The PR and PP WG activities include development of the measures and metrics; establishment of the framework of PR and PP evaluation, the demonstration study using Example Sodium Fast Reactor (ESFR), which included the development of three evaluation approaches; the Case Study using ESFR and four kinds of threat scenarios; the joint study with GIF System Steering Committees (SSCs) of the six reactor design concepts; and the harmonization study with the IAEA's International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO). This paper reviews the status of GIF PR and PP studies and identifies the challenges and directions for applying the methodology to evaluate future nuclear energy systems in Japan. (author)

  16. Contribution to the methodology of safety evaluation - and licensing of reloading cycle for PWR type reactors

    International Nuclear Information System (INIS)

    Esteves, R.G.

    1981-01-01

    A simplified methodology for evaluating a reload safety cycle is presented. This methodology consists in selecting for each foreseen accident, the nuclear key reload safety parameters which determine the accident evolution. So, each key reload parameter is calculated and compared with its value for the first cycle. Those accidents, which have their key reload parameter bounded by the values of the first cycle do not need reanalise. Extension of the validity of this methodology when there exists change of fuel supplier is commented. (Author) [pt

  17. Review of evaluation on ecological carrying capacity: The progress and trend of methodology

    Science.gov (United States)

    Wang, S. F.; Xu, Y.; Liu, T. J.; Ye, J. M.; Pan, B. L.; Chu, C.; Peng, Z. L.

    2018-02-01

    The ecological carrying capacity (ECC) has been regarded as an important reference to indicate the level of regional sustainable development since the very beginning of twenty-first century. By a brief review of the main progress in ECC evaluation methodologies in recent five years, this paper systematically discusses the features and differences of these methods and expounds the current states and future development trend of ECC methodology. The result shows that further exploration in terms of the dynamic, comprehensive and intelligent assessment technologies needs to be provided in order to form a unified and scientific ECC methodology system and to produce a reliable basis for environmental-economic decision-makings.

  18. Two Stage Fuzzy Methodology to Evaluate the Credit Risks of Investment Projects

    OpenAIRE

    O. Badagadze; G. Sirbiladze; I. Khutsishvili

    2014-01-01

    The work proposes a decision support methodology for the credit risk minimization in selection of investment projects. The methodology provides two stages of projects’ evaluation. Preliminary selection of projects with minor credit risks is made using the Expertons Method. The second stage makes ranking of chosen projects using the Possibilistic Discrimination Analysis Method. The latter is a new modification of a well-known Method of Fuzzy Discrimination Analysis.

  19. Reliability of structures by using probability and fatigue theories

    International Nuclear Information System (INIS)

    Lee, Ouk Sub; Kim, Dong Hyeok; Park, Yeon Chang

    2008-01-01

    Methodologies to calculate failure probability and to estimate the reliability of fatigue loaded structures are developed. The applicability of the methodologies is evaluated with the help of the fatigue crack growth models suggested by Paris and Walker. The probability theories such as the FORM (first order reliability method), the SORM (second order reliability method) and the MCS (Monte Carlo simulation) are utilized. It is found that the failure probability decreases with the increase of the design fatigue life and the applied minimum stress, the decrease of the initial edge crack size, the applied maximum stress and the slope of Paris equation. Furthermore, according to the sensitivity analysis of random variables, the slope of Pairs equation affects the failure probability dominantly among other random variables in the Paris and the Walker models

  20. Fatigue life assessment of free spanning pipelines containing corrosion defects

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Rita de Kassia D.; Campello, Georga C.; Matt, Cyntia G. da Costa; Benjamin, Adilson C.; Franciss, Ricardo [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2009-12-19

    The free spanning pipelines assessment is a highlighted issue to be considered during the project and maintenance of the submarine pipelines. It is required to evaluate the fatigue life and the maximum stress due to VIV (Vortex Induced Vibration) as well as wave forces when applicable in case of shallow water. The code DNV-RP-F105 (2006) presents a methodology to calculate the fatigue life for free spanning pipelines. Such methodology however considers the pipe with no kind of defects. Nevertheless, sometimes corrosion defects are detected in periodic inspections and therefore their effects need to be taken into account in the fatigue life evaluation. The purpose of this paper thus is to present a procedure to assess the influence of the corrosion defects in the fatigue life of free spanning pipelines. Some FE analyses were performed to determine the stress concentrate factor (SCF) of the corrosion defects, which were used as input in the methodology presented in the code DNV-RP-F105 (2006). Curves of damage and so lifetime have been generated as function of the span length and water depth. As a practical application, this methodology was applied to a sub sea pipeline with several corrosion defects, localized in shallow water offshore Brazil. (author)

  1. Evaluating electronic performance support systems: A methodology focused on future use-in-practice

    NARCIS (Netherlands)

    Collis, Betty; Verwijs, C.A.

    1995-01-01

    Electronic performance support systems, as an emerging type of software environment, present many new challenges in relation to effective evaluation. In this paper, a global approach to a 'usage-orientated' evaluation methodology for software product is presented, followed by a specific example of

  2. Methodologies for environmental, micro- and macro-economic evaluation of bioenergy systems

    NARCIS (Netherlands)

    Broek, R. van den; Wijk, A. van

    2006-01-01

    An overview is given of methodologies used for evaluation of bioenergy systems on envoronmental, micro- and macro-economic spects. To evaluate micro-economic impacts net present value and annualised cost calculation are used. For environmental impacts, methods used are: qualitative studies, energy

  3. Fatigue testing of wood composites for aerogenerator blades. Pt. 11: Assessment of fatigue damage accumulation using a fatigue modulus approach

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, C L; Ansell, M P [Bath Univ. (United Kingdom)

    1996-12-31

    Stress-strain hysteresis loops have been captured during fatigue tests performed at R=10 (compression-compression) and R=0.1 (tension-tension) on Khaya epoxy wood composites. A fatigue modulus approach, proposed by Hwang and Han in 1989, has been applied to the data and a relationship established between the initial change in fatigue modulus and fatigue life. By following changes in fatigue modulus during the first 100 test cycles it is possible to predict the life of the sample allowing rapid evaluation of the fatigue performance of wood composites. Fatigue modulus values have also been calculated for hysteresis loops captured during complex load - time history tests. Similar trends in change in fatigue modulus suggest that this approach could be used in complex loading conditions to evaluate fatigue damage accumulation and predict fatigue life. (Author)

  4. Establishment of a JSME code for the evaluation of high-cycle thermal fatigue in mixing tees

    International Nuclear Information System (INIS)

    Moriya, Shoichi; Fukuda, Toshihiko; Matsunaga, Tomoya; Hirayama, Hiroshi; Shiina, Kouji; Tanimoto, Koichi

    2004-01-01

    This paper describes a JSME code for high-cycle thermal fatigue evaluation by thermal striping in mixing tees with hot and cold water flows. The evaluation of thermal striping in a mixing tee has four steps to screen design parameters one-by-one according to the severity of the thermal load assessed from design conditions using several evaluation charts. In order to make these charts, visualization tests with acrylic pipes and temperature measurement tests with metal pipes were conducted. The influence of the configurations of mixing tees, flow velocity ratio, pipe diameter ratio and so on was examined from the results of the experiments. This paper makes a short mention of the process of providing these charts. (author)

  5. 3-D finite element stress analysis for fatigue design and evaluation: a parametric study of MOV(Motor Operated Valve)

    International Nuclear Information System (INIS)

    Kim, Hyeong Keun; Lee, Sang Min; Chang, Yoon Suk; Choi, Jae Boong; Kim, Young Jin; Kim, Yun Jae

    2004-01-01

    In this paper, a new procedure is proposed to accomplish the primary plus secondary stress(P+Q) at the 'structural element' instead of 'transition element'. For the P+Q evaluation, the calculated stresses by FEA are linearized along a stress classification line to extract the stress category, then the stress intensity is calculated to compare with the 3Sm limit. Also, in this paper, the 'design by analysis' criteria, adopted fundamental concepts and a new approach to calculate Ke factors are explained. The new procedure combined with 3-D FEA has been applied to motor operated valve in order to the over conservatism and the rack of margin. The evaluation results show a good applicability and can be utilized for fatigue life evaluation by using P+Q

  6. Fatigue life evaluation based on welding residual stress relaxation and notch strain approach for cruciform welded joint

    International Nuclear Information System (INIS)

    Han, Jeong Woo; Han, Seung Ho; Shin, Byung Chun; Kim, Jae Hoon

    2003-01-01

    The fatigue strength of welded joint is influenced by the welding residual stress which is relaxed depending on local stress distributed in vicinity of stress raisers, eg. under cut, overlap and blow hole. To evaluate its fatigue life the geometry of the stress raisers and the welding residual stress should be taken into account. The several methods based on notch strain approach have been proposed in order to consider the two factors above mentioned. These methods, however, have shown considerable differences between analytical and experimental results. It is due to the fact that the amount of the relaxed welding residual stress evaluated by the cyclic stress-strain relationship do not correspond with that occurred in reality. In this paper the residual stress relaxation model based on experimental results was used in order to reduce the discrepancy of the estimated amount of the relaxed welding residual stress. Under an assumption of the superimposition of the relaxed welding residual stress and the local stress, a modified notch strain approach was proposed and verified to the cruciform welded joint

  7. Muscle Deoxygenation Causes Muscle Fatigue

    Science.gov (United States)

    Murthy, G.; Hargens, A. R.; Lehman, S.; Rempel, D.

    1999-01-01

    Muscle fatigue is a common musculoskeletal disorder in the work place, and may be a harbinger for more disabling cumulative trauma disorders. Although the cause of fatigue is multifactorial, reduced blood flow and muscle oxygenation may be the primary factor in causing muscle fatigue during low intensity muscle exertion. Muscle fatigue is defined as a reduction in muscle force production, and also occurs among astronauts who are subjected to postural constraints while performing lengthy, repetitive tasks. The objectives of this research are to: 1) develop an objective tool to study the role of decreased muscle oxygenation on muscle force production, and 2) to evaluate muscle fatigue during prolonged glovebox work.

  8. Methodologies for evaluating long-term stabilization designs of uranium mill tailings impoundments

    International Nuclear Information System (INIS)

    Nelson, J.D.; Abt, S.R.; Volpe, R.L.; Van Zye, D.; Hinkle, N.E.; Staub, W.P.

    1986-06-01

    Uranium mill tailings impoundments require long-term (200 to 1000 years) stabilization. This report reviews currently available methodologies for evaluating factors that can have a significant influence on tailings stabilization and develops methodologies in technical areas where none presently exist. Mill operators can use these methodologies to assist with (1) the selection of sites for mill tailings impoundments, (2) the design of stable impoundments, and (3) the development of reclamation plans for existing impoundments. These methodologies would also be useful for regulatory agency evaluations of proposals in permit or license applications. Methodologies were reviewed or developed in the following technical areas: (1) prediction of the Probable Maximum Precipitation (PMP) and an accompanying Probable Maximum Flood (PMF); (2) prediction of the stability of local and regional fluvial systems; (3) design of impoundment surfaces resistant to gully erosion; (4) evaluation of the potential for surface sheet erosion; (5) design of riprap for protecting embankments from channel flood flow and overland flow; (6) selection of riprap with appropriate durability for its intended use; and (7) evaluation of oversizing required for marginal quality riprap

  9. Evaluation of the Fatigue Performance and Degradability of Resorbable PLDLLA-TMC Osteofixations

    Science.gov (United States)

    Landes, Constantin; Ballon, Alexander; Ghanaati, Shahram; Ebel, Daniel; Ulrich, Dieter; Spohn, Uwe; Heunemann, Ute; Sader, Robert; Jaeger, Raimund

    2013-01-01

    The fatigue performance of explanted in-situ degraded osteofixations/osteosyntheses, fabricated from poly (70L-lactide-co-24DL-lactide-6-trimethylane-carbonate or PLDLLA-TMC) copolymer was compared to that of virgin products. The fatigue test was performed on 21 explants retrieved from 12 women and 6 men; 16-46 years by a custom-designed three-point bend apparatus using a staircase method and a specified failure criterion (an increase of the deflection of the specimen > 1 mm) with run-out designated as “no failure” after 150,000 loading cycles. While all the virgin products showed run-out at 38N, all of the specimens fabricated from explants failed at this load level. For the explant specimens, although there was a trend of decreased failure load with increased in-situ time, this decrease was pronounced after 4 months in-situ, however, not yet statistically significant, while a 6-month in-situ explant had significantly less failure load. Three and four month in-situ explants had highly significant differences in failure load between measurements close and distant to the osteotomy line: p=0.0017 (the region of maximum load in-situ). In the virgin products, there were only traces of melt joining and cooling, left from a stage in the manufacturing process. For the implants retrieved after 4.5 months in-situ, the fracture surfaces showed signs of degradation of the implants, possibly caused by hydrolysis, and for those retrieved after 9 months in-situ, there were cracks and pores. Thus, the morphological results are consistent with those obtained in the fatigue test. The present results suggest that resorbable osteofixations fabricated from PLDLLA-TMC are stable enough to allow loading of the healing bone and degrade reliably PMID:24363786

  10. Evaluation of muscle fatigue of wheelchair basketball players with spinal cord injury using recurrence quantification analysis of surface EMG.

    Science.gov (United States)

    Uzun, S; Pourmoghaddam, A; Hieronymus, M; Thrasher, T A

    2012-11-01

    Wheelchair basketball is the most popular exercise activity among individuals with spinal cord injury (SCI). The purpose of this study was to investigate muscular endurance and fatigue in wheelchair basketball athletes with SCI using surface electromyography (SEMG) and maximal torque values. SEMG characteristics of 10 wheelchair basketball players (WBP) were compared to 13 able-bodied basketball players and 12 sedentary able-bodied subjects. Participants performed sustained isometric elbow flexion at 50% maximal voluntary contraction until exhaustion. Elbow flexion torque and SEMG signals were recorded from three elbow flexor muscles: biceps brachii longus, biceps brachii brevis and brachioradialis. SEMG signals were clustered into 0.5-s epochs with 50% overlap. Root mean square (RMS) and median frequency (MDF) of SEMG signals were calculated for each muscle and epoch as traditional fatigue monitoring. Recurrence quantification analysis was used to extract the percentage of determinism (%DET) of SEMG signals. The slope of the %DET for basketball players and WBP showed slower increase with time than the sedentary able-bodied control group for three different elbow flexor muscles, while no difference was observed for the slope of the %DET between basketball and WBP. This result indicated that the athletes are less fatigable during the task effort than the nonathletes. Normalized MDF slope decay exhibited similar results between the groups as %DET, while the slope of the normalized RMS failed to show any significant differences among the groups (p > 0.05). MDF and %DET could be useful for the evaluation of muscle fatigue in wheelchair basketball training. No conclusions about special training for WBP could be determined.

  11. Methodology for the evaluation process in the director´s preparation from education.

    Directory of Open Access Journals (Sweden)

    Humberto Clemente Calderón Echevarría

    2014-03-01

    Full Text Available The presented work proposes a methodology oriented to the evaluation of the process of director´s preparation which may contribute to the improvement of the program. It explains the need of the evaluation, activity as such, indicators to evaluate, methods and techniques to be used and the steps in which have to be done. Until now doesn´t exist a methodology which can evaluate the process of directors’ preparation in the educational sector. The development of this methodology has as a background the result obtained by means of different investigations made in the Provincial Post Office and that later were applied in the Provincial Department of Education. Nowadays is perfected in the Pedagogical University "Capitán Silverio Blanco Núñez", thus, the employment opportunities in similar processes of other entities. In the proposed methodology is conceived that the process evaluation of the director’s preparation flows out in a cyclical manner, continuous, flexible, and interactive, away from the traditional linear formula, rigid and schematic. From the above idea it can be identify four stages, and the relevant procedures, the evaluation of the process of directors’ preparation in education.

  12. Application of quality improvement analytic methodology in emergency medicine research: A comparative evaluation.

    Science.gov (United States)

    Harries, Bruce; Filiatrault, Lyne; Abu-Laban, Riyad B

    2018-05-30

    Quality improvement (QI) analytic methodology is rarely encountered in the emergency medicine literature. We sought to comparatively apply QI design and analysis techniques to an existing data set, and discuss these techniques as an alternative to standard research methodology for evaluating a change in a process of care. We used data from a previously published randomized controlled trial on triage-nurse initiated radiography using the Ottawa ankle rules (OAR). QI analytic tools were applied to the data set from this study and evaluated comparatively against the original standard research methodology. The original study concluded that triage nurse-initiated radiographs led to a statistically significant decrease in mean emergency department length of stay. Using QI analytic methodology, we applied control charts and interpreted the results using established methods that preserved the time sequence of the data. This analysis found a compelling signal of a positive treatment effect that would have been identified after the enrolment of 58% of the original study sample, and in the 6th month of this 11-month study. Our comparative analysis demonstrates some of the potential benefits of QI analytic methodology. We found that had this approach been used in the original study, insights regarding the benefits of nurse-initiated radiography using the OAR would have been achieved earlier, and thus potentially at a lower cost. In situations where the overarching aim is to accelerate implementation of practice improvement to benefit future patients, we believe that increased consideration should be given to the use of QI analytic methodology.

  13. Evaluation of the BPMN According to the Requirements of the Enterprise Architecture Methodology

    Directory of Open Access Journals (Sweden)

    Václav Řepa

    2012-04-01

    Full Text Available This article evaluates some characteristics of the Business Process Modelling Notation from the perspective of the business system modelling methodology. Firstly the enterprise architecture context of the business process management as well as the importance of standards are discussed. Then the Business System Modelling Methodology is introduced with special attention paid to the Business Process Meta-model as a basis for the evaluation of the BPMN features. Particular basic concepts from the Business Process Meta-model are mapped to the usable constructs of the BPMN and related issues are analysed. Finally the basic conclusions are made and the general context is discussed.

  14. Fatigue approach for addressing environmental effects in fatigue usage calculation

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, Paul; Rudolph, Juergen [AREVA GmbH, Erlangen (Germany); Steinmann, Paul [Erlangen-Nuremberg Univ., erlangen (Germany). Chair of Applied Mechanics

    2015-04-15

    Laboratory tests consider simple trapezoidal, triangle, and sinusoidal signals. However, actual plant components are characterized by complex loading patterns and periods of holds. Fatigue tests in water environment show, that the damage from a realistic strain variation or the presence of hold-times within cyclic loading results in an environmental reduction factor (Fen) only half that of a simple waveform. This study proposes a new fatigue approach for addressing environmental effects in fatigue usage calculation for class 1 boiler and pressure vessel reactor components. The currently accepted method of fatigue assessment has been used as a base model and all cycles, which have been comparable with realistic fatigue tests, have been excluded from the code-based fatigue calculation and evaluated directly with the test data. The results presented show that the engineering approach can successfully be integrated in the code-based fatigue assessment. The cumulative usage factor can be reduced considerably.

  15. Fatigue approach for addressing environmental effects in fatigue usage calculation

    International Nuclear Information System (INIS)

    Wilhelm, Paul; Rudolph, Juergen; Steinmann, Paul

    2015-01-01

    Laboratory tests consider simple trapezoidal, triangle, and sinusoidal signals. However, actual plant components are characterized by complex loading patterns and periods of holds. Fatigue tests in water environment show, that the damage from a realistic strain variation or the presence of hold-times within cyclic loading results in an environmental reduction factor (Fen) only half that of a simple waveform. This study proposes a new fatigue approach for addressing environmental effects in fatigue usage calculation for class 1 boiler and pressure vessel reactor components. The currently accepted method of fatigue assessment has been used as a base model and all cycles, which have been comparable with realistic fatigue tests, have been excluded from the code-based fatigue calculation and evaluated directly with the test data. The results presented show that the engineering approach can successfully be integrated in the code-based fatigue assessment. The cumulative usage factor can be reduced considerably.

  16. Strength and fatigue life evaluation of composite laminate with embedded sensors

    Science.gov (United States)

    Rathod, Vivek T.; Hiremath, S. R.; Roy Mahapatra, D.

    2014-04-01

    Prognosis regarding durability of composite structures using various Structural Health Monitoring (SHM) techniques is an important and challenging topic of research. Ultrasonic SHM systems with embedded transducers have potential application here due to their instant monitoring capability, compact packaging potential toward unobtrusiveness and noninvasiveness as compared to non-contact ultrasonic and eddy current techniques which require disassembly of the structure. However, embedded sensors pose a risk to the structure by acting as a flaw thereby reducing life. The present paper focuses on the determination of strength and fatigue life of the composite laminate with embedded film sensors like CNT nanocomposite, PVDF thin films and piezoceramic films. First, the techniques of embedding these sensors in composite laminates is described followed by the determination of static strength and fatigue life at coupon level testing in Universal Testing Machine (UTM). Failure mechanisms of the composite laminate with embedded sensors are studied for static and dynamic loading cases. The coupons are monitored for loading and failure using the embedded sensors. A comparison of the performance of these three types of embedded sensors is made to study their suitability in various applications. These three types of embedded sensors cover a wide variety of applications, and prove to be viable in embedded sensor based SHM of composite structures.

  17. Evaluation of Fatigue Crack Propagation of Gears Considering Uncertainties in Loading and Material Properties

    Directory of Open Access Journals (Sweden)

    Haileyesus B. Endeshaw

    2017-11-01

    Full Text Available Failure prediction of wind turbine gearboxes (WTGs is especially important since the maintenance of these components is not only costly but also causes the longest downtime. One of the most common causes of the premature fault of WTGs is attributed to the fatigue fracture of gear teeth due to fluctuating and cyclic torque, resulting from stochastic wind loading, transmitted to the gearbox. Moreover, the fluctuation of the torque, as well as the inherent uncertainties of the material properties, results in uncertain life prediction for WTGs. It is therefore essential to quantify these uncertainties in the life estimation of gears. In this paper, a framework, constituted by a dynamic model of a one-stage gearbox, a finite element method, and a degradation model for the estimation of fatigue crack propagation in gear, is presented. Torque time history data of a wind turbine rotor was scaled and used to simulate the stochastic characteristic of the loading and uncertainties in the material constants of the degradation model were also quantified. It was demonstrated that uncertainty quantification of load and material constants provides a reasonable estimation of the distribution of the crack length in the gear tooth at any time step.

  18. An integrated methodology for the dynamic performance and reliability evaluation of fault-tolerant systems

    International Nuclear Information System (INIS)

    Dominguez-Garcia, Alejandro D.; Kassakian, John G.; Schindall, Joel E.; Zinchuk, Jeffrey J.

    2008-01-01

    We propose an integrated methodology for the reliability and dynamic performance analysis of fault-tolerant systems. This methodology uses a behavioral model of the system dynamics, similar to the ones used by control engineers to design the control system, but also incorporates artifacts to model the failure behavior of each component. These artifacts include component failure modes (and associated failure rates) and how those failure modes affect the dynamic behavior of the component. The methodology bases the system evaluation on the analysis of the dynamics of the different configurations the system can reach after component failures occur. For each of the possible system configurations, a performance evaluation of its dynamic behavior is carried out to check whether its properties, e.g., accuracy, overshoot, or settling time, which are called performance metrics, meet system requirements. Markov chains are used to model the stochastic process associated with the different configurations that a system can adopt when failures occur. This methodology not only enables an integrated framework for evaluating dynamic performance and reliability of fault-tolerant systems, but also enables a method for guiding the system design process, and further optimization. To illustrate the methodology, we present a case-study of a lateral-directional flight control system for a fighter aircraft

  19. A quality evaluation methodology of health web-pages for non-professionals.

    Science.gov (United States)

    Currò, Vincenzo; Buonuomo, Paola Sabrina; Onesimo, Roberta; de Rose, Paola; Vituzzi, Andrea; di Tanna, Gian Luca; D'Atri, Alessandro

    2004-06-01

    The proposal of an evaluation methodology for determining the quality of healthcare web sites for the dissemination of medical information to non-professionals. Three (macro) factors are considered for the quality evaluation: medical contents, accountability of the authors, and usability of the web site. Starting from two results in the literature the problem of whether or not to introduce a weighting function has been investigated. This methodology has been validated on a specialized information content, i.e., sore throats, due to the large interest such a topic enjoys with target users. The World Wide Web was accessed using a meta-search system merging several search engines. A statistical analysis was made to compare the proposed methodology with the obtained ranks of the sample web pages. The statistical analysis confirms that the variables examined (per item and sub factor) show substantially similar ranks and are capable of contributing to the evaluation of the main quality macro factors. A comparison between the aggregation functions in the proposed methodology (non-weighted averages) and the weighting functions, derived from the literature, allowed us to verify the suitability of the method. The proposed methodology suggests a simple approach which can quickly award an overall quality score for medical web sites oriented to non-professionals.

  20. Methodological Challenges to Economic Evaluations of Vaccines: Is a Common Approach Still Possible?

    Science.gov (United States)

    Jit, Mark; Hutubessy, Raymond

    2016-06-01

    Economic evaluation of vaccination is a key tool to inform effective spending on vaccines. However, many evaluations have been criticised for failing to capture features of vaccines which are relevant to decision makers. These include broader societal benefits (such as improved educational achievement, economic growth and political stability), reduced health disparities, medical innovation, reduced hospital beds pressures, greater peace of mind and synergies in economic benefits with non-vaccine interventions. Also, the fiscal implications of vaccination programmes are not always made explicit. Alternative methodological frameworks have been proposed to better capture these benefits. However, any broadening of the methodology for economic evaluation must also involve evaluations of non-vaccine interventions, and hence may not always benefit vaccines given a fixed health-care budget. The scope of an economic evaluation must consider the budget from which vaccines are funded, and the decision-maker's stated aims for that spending to achieve.

  1. Rhodiola rosea for physical and mental fatigue: a systematic review

    Directory of Open Access Journals (Sweden)

    Ishaque Sana

    2012-05-01

    Full Text Available Abstract Background Rhodiola rosea (R. rosea is grown at high altitudes and northern latitudes. Due to its purported adaptogenic properties, it has been studied for its performance-enhancing capabilities in healthy populations and its therapeutic properties in a number of clinical populations. To systematically review evidence of efficacy and safety of R. rosea for physical and mental fatigue. Methods Six electronic databases were searched to identify randomized controlled trials (RCTs and controlled clinical trials (CCTs, evaluating efficacy and safety of R. rosea for physical and mental fatigue. Two reviewers independently screened the identified literature, extracted data and assessed risk of bias for included studies. Results Of 206 articles identified in the search, 11 met inclusion criteria for this review. Ten were described as RCTs and one as a CCT. Two of six trials examining physical fatigue in healthy populations report R. rosea to be effective as did three of five RCTs evaluating R. rosea for mental fatigue. All of the included studies exhibit either a high risk of bias or have reporting flaws that hinder assessment of their true validity (unclear risk of bias. Conclusion Research regarding R. rosea efficacy is contradictory. While some evidence suggests that the herb may be helpful for enhancing physical performance and alleviating mental fatigue, methodological flaws limit accurate assessment of efficacy. A rigorously-designed well reported RCT that minimizes bias is needed to determine true efficacy of R. rosea for fatigue.

  2. An evaluation on the effect of reversed plastic zone on the fatigue crack opening behavior under 2-D plane stress

    International Nuclear Information System (INIS)

    Choi, Hyeon Chang

    2005-01-01

    The relationship between fatigue crack opening behavior and the reversed plastic zone sizes is studied. An elastic-plastic Finite Element Analysis (FEA) is performed to examine the opening behavior of fatigue crack, where the contact elements are used in the mesh of the crack tip area. The smaller element size than reversed plastic zone size is used for evaluating the distribution of reversed plastic zone. In the author's previous results the FEA could predict the crack opening level, which crack tip elements were in proportion to the theoretical reversed plastic zone size. It is found that the calculated reversed plastic zone size is related to the theoretical reversed plastic zone size and crack opening level. The calculated reversed plastic zone sizes are almost equal to the reversed plastic zone considering crack opening level obtained by experimental results. It can be possible to predict the crack opening level from the reversed plastic zone size calculated by finite element method. We find that the experimental crack opening levels correspond with the opening values of contact nodes on the calculated reversed plastic zone of finite element simulation

  3. Expanding the Functionality of Speech Recognition in Radiology: Creating a Real-Time Methodology for Measurement and Analysis of Occupational Stress and Fatigue

    OpenAIRE

    Reiner, Bruce I.

    2012-01-01

    While occupational stress and fatigue have been well described throughout medicine, the radiology community is particularly susceptible due to declining reimbursements, heightened demands for service deliverables, and increasing exam volume and complexity. The resulting occupational stress can be variable in nature and dependent upon a number of intrinsic and extrinsic stressors. Intrinsic stressors largely account for inter-radiologist stress variability and relate to unique attributes of th...

  4. Final report of the accident phenomenology and consequence (APAC) methodology evaluation. Spills Working Group

    Energy Technology Data Exchange (ETDEWEB)

    Brereton, S.; Shinn, J. [Lawrence Livermore National Lab., CA (United States); Hesse, D [Battelle Columbus Labs., OH (United States); Kaninich, D. [Westinghouse Savannah River Co., Aiken, SC (United States); Lazaro, M. [Argonne National Lab., IL (United States); Mubayi, V. [Brookhaven National Lab., Upton, NY (United States)

    1997-08-01

    The Spills Working Group was one of six working groups established under the Accident Phenomenology and Consequence (APAC) methodology evaluation program. The objectives of APAC were to assess methodologies available in the accident phenomenology and consequence analysis area and to evaluate their adequacy for use in preparing DOE facility safety basis documentation, such as Basis for Interim Operation (BIO), Justification for Continued Operation (JCO), Hazard Analysis Documents, and Safety Analysis Reports (SARs). Additional objectives of APAC were to identify development needs and to define standard practices to be followed in the analyses supporting facility safety basis documentation. The Spills Working Group focused on methodologies for estimating four types of spill source terms: liquid chemical spills and evaporation, pressurized liquid/gas releases, solid spills and resuspension/sublimation, and resuspension of particulate matter from liquid spills.

  5. A method for calculation of finite fatigue life under multiaxial loading in high-cycle domain

    Directory of Open Access Journals (Sweden)

    M. Malnati

    2014-04-01

    Full Text Available A method for fatigue life assessment in high-cycle domain under multiaxial loading is presented in this paper. This approach allows fatigue assessment under any kind of load history, without limitations. The methodology lies on the construction - at a macroscopic level - of an “indicator” in the form of a set of cycles, representing plasticity that can arise at mesoscopic level throughout fatigue process. During the advancement of the loading history new cycles are created and a continuous evaluation of the damage is made.

  6. SI:FatiguePro 4 Advanced Approach for Fatigue Monitoring

    International Nuclear Information System (INIS)

    Evon, Keith; Gilman, Tim; Carney, Curt

    2012-01-01

    Many nuclear plants are making commitments to implement fatigue monitoring systems in support of license renewal. Current fatigue monitoring systems use the methodology of ASME Code Subarticle NB-3200, which is a design code intended to compute a bounding cumulative usage factor (CUF). The first generation of fatigue monitoring software utilized a simplified, single stress term assumption and classical stress cycle-counting methods that take order into account such as Rainflow or Ordered Overall Range counting. Recently, the NRC has indicated in Regulatory Issue Summary 2008-30 that any fatigue analyses in support of License Renewal should use ASME Code Section III methodologies considering all six stress components. In addition, fatigue calculations for the license renewal term are required to consider the effects of environment. The implementation of a six stress term NB-3200 fatigue calculation to a Boiling Water Reactor (BWR) feedwater nozzle, including environmental effects, is the topic of this paper. Differences in results between the advanced methodology and the simplified methodology are discussed. (author)

  7. Thermal-structural Analysis and Fatigue Life Evaluation of a Parallel Slide Gate Valve in Accordance with ASME B and PVC

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Tae Ho; Han, Jeong Sam [Andong Nat’l Univ., Andong (Korea, Republic of); Jae Seung Choi [Key Valve Technologies Ltd., Siheung (Korea, Republic of)

    2017-02-15

    A parallel slide gate valve (PSGV) is located between the heat recovery steam generator (HRSG) and the steam turbine in a combined cycle power plant (CCPP). It is used to control the flow of steam and runs with repetitive operations such as startups, load changes, and shutdowns during its operation period. Therefore, it is necessary to evaluate the fatigue damage and the structural integrity under a large compressive thermal stress due to the temperature difference through the valve wall thickness during the startup operations. In this paper, the thermal-structural analysis and the fatigue life evaluation of a 16-inch PSGV, which is installed on the HP steam line, is performed according to the fatigue life assessment method described in the ASME B and PVC VIII-2; the method uses the equivalent stress from the elastic stress analysis.

  8. Evaluation of the fatigue macro-cracking behavior of crumb rubber modified bituminous mixes

    Directory of Open Access Journals (Sweden)

    Moreno-Navarro, F.

    2014-09-01

    Full Text Available The use of crumb rubber modified bitumen (CRMB in asphalt mixes is a road engineering technology that has become increasingly important in recent years. Given the many economic and environmental benefits of this type of binder, the goal is to give CRMB the same level of performance as conventional polymer-modified bitumen. The appearance and propagation of cracks due to fatigue phenomena is one of the most common distresses affecting road pavements. Since crumb rubber enhances the mechanical properties of asphalt mixes, it can provide a viable solution for fatigue cracking. This paper presents the results of a comparative analysis of the fatigue-cracking behavior of asphalt mixtures manufactured with crumb rubber modified bitumen and polymer-modified bitumen.El empleo de betunes modificados con polvo de neumático usado en la fabricación de mezclas bituminosas es una de las técnicas que mayor auge está teniendo en los últimos años en la ingeniería de carreteras. Dadas sus grandes ventajas económicas y ambientales, este tipo de ligantes pretende conseguir prestaciones similares a la de los betunes modificados con polímeros utilizados habitualmente. La aparición de fisuras debido a fenómenos de fatiga es una de las patologías más comunes en firmes de carretera. Debido a las mejoras de las propiedades mecánicas del betún aportadas tras la incorporación de polvo de neumático, las mezclas fabricadas con estos ligantes se postulan como una posible solución a dicho problema. En este artículo se lleva a cabo un análisis comparativo del comportamiento a fisuración por fatiga realizado sobre mezclas bituminosas fabricadas con betún modificado con polvo de neumático y con polímeros.

  9. Application of a new methodology to evaluate Dnb limits based on statistical propagation of uncertainties

    International Nuclear Information System (INIS)

    Machado, Marcio Dornellas

    1998-09-01

    One of the most important thermalhydraulics safety parameters is the DNBR (Departure from Nucleate Boiling Ratio). The current methodology in use at Eletronuclear to determine DNBR is extremely conservative and may result in penalties to the reactor power due to an increase plugging level of steam generator tubes. This work uses a new methodology to evaluate DNBR, named mini-RTDP. The standard methodology (STDP) currently in use establishes a limit design value which cannot be surpassed. This limit value is determined taking into account the uncertainties of the empirical correlation used in COBRA IIC/MIT code, modified to Angra 1 conditions. The correlation used is the Westinghouse's W-3 and the minimum DNBR (MDBR) value cannot be less than 1.3. The new methodology reduces the excessive level of conservatism associated with the parameters used in the DNBR calculation, which take most unfavorable values in the STDP methodology, by using their best estimate values. The final goal is to obtain a new DNBR design limit which will provide a margin gain due to more realistic parameters values used in the methodology. (author)

  10. Methodology for evaluating the insect growth regulator (IGR) methoprene incorporated into packaging films

    Science.gov (United States)

    The insect growth regulator methoprene has been impregnated onto various packaging materials to control stored product insects, and is labeled for use in this manner in the United States. Different methodologies were utilized to evaluate efficacy towards Tribolium castaneum (Herbst), the red flour b...

  11. A methodology for evaluating alternative sites for a near-surface radioactive waste repository

    International Nuclear Information System (INIS)

    Watson, S.R.; Brownlow, S.A.

    1986-02-01

    This report addresses the issue of constructing an evaluation procedure for a near-surface radioactive waste repository. It builds on earlier work of the authors, and describes a basis for a practicable methodology for assessing the relative merits of different sites. (author)

  12. Impact Evaluation of Quality Assurance in Higher Education: Methodology and Causal Designs

    Science.gov (United States)

    Leiber, Theodor; Stensaker, Bjørn; Harvey, Lee

    2015-01-01

    In this paper, the theoretical perspectives and general methodological elements of impact evaluation of quality assurance in higher education institutions are discussed, which should be a cornerstone of quality development in higher education and contribute to improving the knowledge about the effectiveness (or ineffectiveness) of quality…

  13. Methodology of site generation for evaluation of the behaviour of radioactive waste storage

    International Nuclear Information System (INIS)

    Ruiz Rivas, C.; Eguilior Diez, S.

    1997-01-01

    The present report summarizes the purpose of methodology for the site generation in the evaluation of high-level radioactive waste storage for long-term. This work is developed into the project Safety analysis long-term of high-level radioactive waste. This project is carried on for CIEMAT and ENRESA

  14. The Research and Evaluation of Serious Games: Toward a Comprehensive Methodology

    Science.gov (United States)

    Mayer, Igor; Bekebrede, Geertje; Harteveld, Casper; Warmelink, Harald; Zhou, Qiqi; van Ruijven, Theo; Lo, Julia; Kortmann, Rens; Wenzler, Ivo

    2014-01-01

    The authors present the methodological background to and underlying research design of an ongoing research project on the scientific evaluation of serious games and/or computer-based simulation games (SGs) for advanced learning. The main research questions are: (1) what are the requirements and design principles for a comprehensive social…

  15. Outcome mapping as methodology to monitor and evaluate community informatics projects: A case study

    CSIR Research Space (South Africa)

    Herselman, M

    2010-10-01

    Full Text Available The purpose of this paper is to indicate how Outcome Mapping (OM) can be used as a methodology to monitor and evaluate a specific developmental informatics project currently under way in the Meraka Institute. OM was applied in the Broadband for All...

  16. Influence of Axial Movement on Fatigue of Profile® Ni-Ti Rotary Instruments: an in vitro evaluation

    Directory of Open Access Journals (Sweden)

    Marie-Chantal Avoaka

    2010-05-01

    Full Text Available The aim of this study was to evaluate the influence of the axial movement and the angle of curve (in degrees on fatigue of nickel-titanium (Ni-Ti ProFile’ rotary endodontic instruments.Ni-Ti ProFile’ rotary instruments (Maillefer SA, Ballaigues, Switzerland, 25 mm long in the range of ISO size 15 to 40 with two tapers (0.4 and 0.6 were evaluated. They are divided in two groups: the instruments with axial movement and those without axial movement. The system used to test the fatigue is maintained in mechanical conditions as close as possible to the clinical situation. The axial movement is in the order of 2mm in corono-apical direction with a frequency of 1Hz. The concave radii incorporating a notched V-form for guiding the instruments were: 5; 7,5 and 10 mm. The rotary system is mounted on an electric handpiece and rotated at 350 rpm speed as recommended by the manufacturers. The instruments are rotated until their separation, and the time, in seconds, is recorded. Statístícal evaluation is undertaken using a two-way t-test to identify significant differences between variables in the study (p <0,05.We found significant statistical difference (p<0,05 between Ni-Ti engine drive ProFile’ instruments incorporating an axial movement and the instruments without axial movement with the same radius of curvature, size and taper.The incorporation of the axial movement increases significantly the life-span of the ProFile’ rotary instruments. This should reduce the risk of the instrument separation during the endodontic treatment

  17. Influence of axial movement on fatigue of ProFile Ni-Ti rotary instruments: an in vitro evaluation.

    Science.gov (United States)

    Avoaka, Marie-Chantal; Haïkel, Youssef

    2010-05-01

    The aim of this study was to evaluate the influence of the axial movement and the angle of curve (in degrees) on fatigue of nickel-titanium (Ni-Ti) ProFile rotary endodontic instruments. Ni-Ti ProFile rotary instruments (Maillefer SA, Ballaigues, Switzerland), 25 mm long in the range of ISO size 15 to 40 with two tapers (0.4 and 0.6) were evaluated. They are divided in two groups: the instruments with axial movement and those without axial movement. The system used to test the fatigue is maintained in mechanical conditions as close as possible to the clinical situation. The axial movement is in the order of 2 mm in corono-apical direction with a frequency of 1 Hz. The concave radii incorporating a notched V-form for guiding the instruments were: 5; 7,5 and 10 mm. The rotary system is mounted on an electric handpiece and rotated at 350 rpm speed as recommended by the manufacturers. The instruments are rotated until their separation, and the time, in seconds, is recorded. Statistical evaluation is undertaken using a two-way t-test to identify significant differences between variables in the study (p engine drive ProFile instruments incorporating an axial movement and the instruments without axial movement with the same radius of curvature, size and taper.The incorporation of the axial movement increases significantly the life-span of the ProFile rotary instruments. This should reduce the risk of the instrument separation during the endodontic treatment.

  18. Influence of axial movement on fatigue of PROFILE* NI-TI rotary instruments: an in vitro evaluation

    Science.gov (United States)

    Avoaka, Marie-Chantal; Haïkel, Youssef

    2010-01-01

    The aim of this study was to evaluate the influence of the axial movement and the angle of curve (in degrees) on fatigue of nickel-titanium (Ni-Ti) ProFile’ rotary endodontic instruments. Ni-Ti ProFile’ rotary instruments (Maillefer SA, Ballaigues, Switzerland), 25 mm long in the range of ISO size 15 to 40 with two tapers (0.4 and 0.6) were evaluated. They are divided in two groups: the instruments with axial movement and those without axial movement. The system used to test the fatigue is maintained in mechanical conditions as close as possible to the clinical situation. The axial movement is in the order of 2mm in corono-apical direction with a frequency of 1Hz. The concave radii incorporating a notched V-form for guiding the instruments were: 5; 7,5 and 10 mm. The rotary system is mounted on an electric handpiece and rotated at 350 rpm speed as recommended by the manufacturers. The instruments are rotated until their separation, and the time, in seconds, is recorded. Statístícal evaluation is undertaken using a two-way t-test to identify significant differences between variables in the study (p engine drive ProFile’ instruments incorporating an axial movement and the instruments without axial movement with the same radius of curvature, size and taper. The incorporation of the axial movement increases significantly the life-span of the ProFile’ rotary instruments. This should reduce the risk of the instrument separation during the endodontic treatment. PMID:20507289

  19. Economic Evaluation Methodology Review on KAERI's Recent Projects

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jin Sam; Kim, Jee Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    In technology utilization, economics evaluation is helpful to R and D program managers by giving them economic information needed to improve the usefulness of their projects. Moreover it can help them to communicate to others participants keeping all of them value-oriented minded through the whole development process. In this context, KAERI(Korea Atomic Energy Research Institute) has been performed economic evaluation on recent some projects. So, in this study, it has been made brief reviews on KAERI's economic evaluation methodology to its recent some projects of which evaluation we engage in, especially PEFP(Proton Engineering frontier Project) and SMART(Small Medium advanced ReacTor): Methodology comparison and their pros and cons

  20. Evaluating the Impact of Conservatism in Industrial Fatigue Analysis of Life-Limited Components

    Directory of Open Access Journals (Sweden)

    Hoole Joshua

    2018-01-01

    Full Text Available This paper presents a review of the conservatism approaches applied by different industrial sectors to the stress-life (S-N analysis of ‘life-limited’ or ‘safe-life’ components. A comparison of the fatigue design standards for 6 industrial sectors identified that the conservatism approaches are highly inconsistent when comparing the areas of variability and uncertainty accounted for along with the conservatism magnitude and method of application. Through the use of a case-study based on the SAE keyhole benchmark and 4340 steel S-N data, the industrial sector which introduces the greatest reduction of a component life-limit was identified as the nuclear sector. The results of the case-study also highlighted that conservatism applied to account for scatter in S-N data currently provides the greatest contribution to the reduction of component life-limits.

  1. Study on heat transfer characteristics in a mixing tee pipe to evaluate for thermal fatigue

    International Nuclear Information System (INIS)

    Miyoshi, Koji; Nakamura, Akira; Utanohara, Yoichi

    2016-01-01

    Thermal fatigue racking may initiate at a tee pipe where high and low temperature fluids flow in from different directions and mix. Thermal stress fluctuations are caused by movement of a hot spot on the pipe inner surface. It is important to investigate the heat transfer from the fluid to the structure around the hot spot. The heat transfer characteristic in the mixing tee pipe was investigated by tests in this study. The unsteady heat transfer coefficients around the hot spot were estimated with the fluid and wall temperature, which were measured with thermocouples. The estimated heat transfer coefficient varied from 1.2 to 3.5 times of the steady state heat transfer coefficient. The heat transfer coefficient was 2.9 times of the steady state value at the position for the maximum stress fluctuation, which was calculated with the measured wall temperature distribution. (author)

  2. A replication and methodological critique of the study "Evaluating drug trafficking on the Tor Network".

    Science.gov (United States)

    Munksgaard, Rasmus; Demant, Jakob; Branwen, Gwern

    2016-09-01

    The development of cryptomarkets has gained increasing attention from academics, including growing scientific literature on the distribution of illegal goods using cryptomarkets. Dolliver's 2015 article "Evaluating drug trafficking on the Tor Network: Silk Road 2, the Sequel" addresses this theme by evaluating drug trafficking on one of the most well-known cryptomarkets, Silk Road 2.0. The research on cryptomarkets in general-particularly in Dolliver's article-poses a number of new questions for methodologies. This commentary is structured around a replication of Dolliver's original study. The replication study is not based on Dolliver's original dataset, but on a second dataset collected applying the same methodology. We have found that the results produced by Dolliver differ greatly from our replicated study. While a margin of error is to be expected, the inconsistencies we found are too great to attribute to anything other than methodological issues. The analysis and conclusions drawn from studies using these methods are promising and insightful. However, based on the replication of Dolliver's study, we suggest that researchers using these methodologies consider and that datasets be made available for other researchers, and that methodology and dataset metrics (e.g. number of downloaded pages, error logs) are described thoroughly in the context of web-o-metrics and web crawling. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Creep-fatigue evaluation method for type 304 and 316FR SS

    International Nuclear Information System (INIS)

    Wada, Y.; Aoto, K.; Ueno, F.

    1997-01-01

    For long-term creep-fatigue of Type 304SS, intergranular failure is dominant in the case of significant life reduction. It is considered that this phenomenon has its origin in the grain boundary sliding as observed in cavity-type creep-rupture. Accordingly a simplified procedure to estimate intergranular damages caused by the grain boundary sliding is presented in connection with the secondary creep. In the conventional ductility exhaustion method, failure ductility includes plastic strain, and damage estimation is based on the primary creep strain, which is recoverable during strain cycling. Therefore the accumulated creep strain becomes a very large value, and quite different from grain boundary sliding strain. As a new concept on ductility exhaustion, the product of secondary creep rate and time to rupture (Monkman-Grant product) is applied to fracture ductility, and grain boundary sliding strain is approximately estimated using the accumulated secondary creep strain. From the new concept it was shown that the time fraction rule and the conventional ductility exhaustion method can be derived analytically. Furthermore an advanced method on cyclic stress relaxation was examined. If cyclic plastic strain hardening is softened thermally during strain hold, cyclic creep strain behaviour is also softened. An unrecoverable accumulated primary creep strain causes hardening of the primary creep, and the reduction of deformation resistance to the secondary creep caused by thermal softening accelerates grain boundary sliding rate. As the results creep damages depend not on applied stress but on effective stress. The new concept ductility exhaustion method based on the above consideration leads up to simplified time fraction estimation method only by continuous cycling fatigue and monotonic creep which was already developed in PNC for Monju design guide. This method gave good life prediction for the intergranular failure mode and is convenient for design use on the elastic

  4. An investigative study towards constructing anthropocentric Man-Machine System design evaluation methodology

    International Nuclear Information System (INIS)

    Yoshikawa, H.; Gofuku, A.; Itoh, T.; Sasaki, K.

    1992-01-01

    A methodological investigation has been conducted for evaluating the reliability of man-machine interaction in the total Man-Machine System (MMS) from the view-point of safety maintenance for emergent situations of nuclear power plant. Basic considerations in our study are: (i) what are the MMS design data to be evaluated, (ii) how are those MMS design data should be treated, and (iii) how the introduction effects of various operator support tools can be evaluated. The methods of both qualitative and quantitative MMS design evaluation are summarized in this paper, with the system architecture based on man-machine interaction simulation and the related cognitive human error factor analysis. (author)

  5. Prospective evaluation of a 12-week walking exercise program and its effect on fatigue in prostate cancer patients undergoing radical external beam radiotherapy.

    Science.gov (United States)

    Truong, Pauline T; Gaul, Catherine A; McDonald, Rachel E; Petersen, Ross B; Jones, Stuart O; Alexander, Abraham S; Lim, Jan T W; Ludgate, Charles

    2011-08-01

    To evaluate tolerability and compliance to a walking exercise program and its effect on fatigue during and after radical external beam radiation therapy (EBRT) for prostate cancer. A total of 50 subjects with prostate cancer undergoing EBRT over 6 to 8 weeks were prospectively accrued to an exercise intervention group, matched for age and clinical characteristics to 30 subjects in a historical control group who underwent EBRT with no specific exercise intervention. Starting 1 week before EBRT, exercise participants performed moderate-intensity walking targeting 60% to 70% age-predicted maximum heart rate, at least 20 min/d, 3 d/wk over 12 weeks. The Brief Fatigue Inventory was administered at baseline, mid-EBRT (week 3-4), end-EBRT (week 6-8), and 6 months post-EBRT. Of 50, 42 (84%) of exercise participants completed the walking program. There were no cardiovascular complications, musculoskeletal injuries, or other adverse events. A total of 89% subjects reported "Good-Excellent" satisfaction during and up to 6 months post-EBRT. Fatigue in control subjects escalated from baseline to end-EBRT, remaining high at 6 months post-EBRT (P[r] = 0.03). In contrast, mean total fatigue scores in exercise subjects were stable from baseline up to 6 months post-EBRT (P = 0.52). Trends for higher fatigue interference with quality of life were observed in the control group as compared with the exercise group. Moderate-intensity walking exercise during radical EBRT is safe and feasible. The high convenience and satisfaction ratings, in conjunction with the observed fatigue trends, indicate that this activity has the potential to attenuate fatigue and improve quality of life for patients with localized prostate cancer undergoing curative therapy.

  6. Methodology for evaluating pattern transfer completeness in inkjet printing with irregular edges

    Science.gov (United States)

    Huang, Bo-Cin; Chan, Hui-Ju; Hong, Jian-Wei; Lo, Cheng-Yao

    2016-06-01

    A methodology for quantifying and qualifying pattern transfer completeness in inkjet printing through examining both pattern dimensions and pattern contour deviations from reference design is proposed, which enables scientifically identifying and evaluating inkjet-printed lines, corners, circles, ellipses, and spirals with irregular edges of bulging, necking, and unpredictable distortions resulting from different process conditions. This methodology not only avoids differences in individual perceptions of ambiguous pattern distortions but also indicates the systematic effects of mechanical stresses applied in different directions to a polymer substrate, and is effective for both optical and electrical microscopy in direct and indirect lithography or lithography-free patterning.

  7. Methodology for evaluating pattern transfer completeness in inkjet printing with irregular edges

    International Nuclear Information System (INIS)

    Huang, Bo-Cin; Chan, Hui-Ju; Lo, Cheng-Yao; Hong, Jian-Wei

    2016-01-01

    A methodology for quantifying and qualifying pattern transfer completeness in inkjet printing through examining both pattern dimensions and pattern contour deviations from reference design is proposed, which enables scientifically identifying and evaluating inkjet-printed lines, corners, circles, ellipses, and spirals with irregular edges of bulging, necking, and unpredictable distortions resulting from different process conditions. This methodology not only avoids differences in individual perceptions of ambiguous pattern distortions but also indicates the systematic effects of mechanical stresses applied in different directions to a polymer substrate, and is effective for both optical and electrical microscopy in direct and indirect lithography or lithography-free patterning. (paper)

  8. Environmental and sanitary evaluation of electro-nuclear sites: methodological research and application to prospective scenarios

    International Nuclear Information System (INIS)

    2004-12-01

    In the framework of the radioactive wastes disposal of the law of 1991, an exchange forum constituted by ANDRA, CEA, COGEMA, EdF, Framatome-ANP and IRSN implemented an environmental and sanitary evaluation of the different methods of radioactive wastes management. This report presents the six studies scenarios, the proposed methodology, the application to the six scenarios and the analysis of the results which showed the efficiency of the different recycling options towards the electronuclear cycle impacts limitation, and a technical conclusion illustrated by improvement possibilities of the methodology. (A.L.B.)

  9. Formation of a Methodological Approach to Evaluating the State of Management of Enterprise Flow Processes

    Directory of Open Access Journals (Sweden)

    Dzobko Iryna P.

    2016-02-01

    Full Text Available The formation of a methodological approach to evaluating management of the state of enterprise flow processes has been considered. Proceeding from the developed and presented in literary sources theoretical propositions on organization of management of enterprise flow processes, the hypothesis of the study is correlation of quantitative and qualitative evaluations of management effectiveness and formation of the integral index on their basis. The article presents stages of implementation of a methodological approach to evaluating the state of management of enterprise flow processes, which implies indicating the components, their characteristics and methods of research. The composition of indicators, on the basis of which it is possible to evaluate effectiveness of management of enterprise flow processes, has been determined. Grouping of such indicators based on the flow nature of enterprise processes has been performed. The grouping of indicators is justified by a pairwise determination of canonical correlations between the selected groups (the obtained high correlation coefficients confirmed the author’s systematization of indicators. It is shown that a specificity of the formation of a methodological approach to evaluating the state of management of enterprise flow processes requires expansion in the direction of aggregation of the results and determination of factors that influence effectiveness of flow processes management. The article carries out such aggregation using the factor analysis. Distribution of a set of objects into different classes according to the results of the cluster analysis has been presented. To obtain an integral estimation of effectiveness of flow processes management, the taxonomic index of a multidimensional object has been built. A peculiarity of the formed methodological approach to evaluating the state of management of enterprise flow processes is in the matrix correlation of integral indicators calculated on

  10. Economic evaluation studies in nuclear medicine. A methodological review of the literature

    International Nuclear Information System (INIS)

    Gambhir, S.S.; Schwimmer, J.

    2000-01-01

    The growing need for evaluation of the utility of new nuclear medicine technologies has spawned a few economic studies ranging from preliminary indications of cost savings to complete decision analysis models incorporating costs and quality of life. The objective of the current study was to evaluate the methodological quality of economic analyses of nuclear medicine procedures which targeted cost-effectiveness or cost-utility issues published in the medical literature during the years 1985-1999. A computerized literature search was used to identify original investigations from the medical literature which included an economic analysis of a nuclear medicine procedure. Each economic analysis article was evaluated by two independent reviewers for adherence to ten accepted methodological criteria. Of the 29 articles meeting the search criteria, only six (21%) conformed to all ten methodological criteria. Published economic analyses of nuclear medicine procedures usually do not meet accepted methodological standards and could be significantly improved to achieve overall better quality relative to similar analyses in the literature from other medical fields. Continued improvement in the number and quality of economic studies is critically needed for the future competitiveness of nuclear medicine studies

  11. A study on the proliferation resistance evaluation methodology for nuclear energy system

    International Nuclear Information System (INIS)

    Kim, Min Su

    2007-02-01

    The framework of proliferation resistance evaluation methodology, based on attribute analysis and scenario analysis, for nuclear energy system is suggested in order to allow for the comprehensive assessment of proliferation resistance by addressing the intrinsic and extrinsic features of nuclear energy system. Proliferation resistance is viewed within the context of the success tree model of proliferator's diversion attempt and expressed by the value of top event probability of the success tree model. This study focused on the method that the value of top event is estimated. The methodology uses two different methods to quantify the likelihood of basic events constituting the top event. The likelihood of basic event success affected by intrinsic feature of nuclear energy system was assessed by using multi-attribute utility theory and likelihood of basic event related to the diversion detection measures was assessed by direct expert elicitation. The value of top event was calculated based on the intersection of probabilities of basic event success. Feasibility of the methodology was explored by applying it to selected reference nuclear energy systems. System-Integrated Modular Advanced Reactor (SMART) system and Light Water Reactor (LWR) were chosen as reference systems and the value proliferation resistance of SMART and LWR were evaluated. Characteristics of inherent features and hypothesized safeguards measures of both systems were identified and used as input data to evaluate proliferation resistance. The results and conclusions are applicable only within the context of subjectivity of this methodology

  12. Research on Evaluation Methodology for High Temperature Components and Technical Issues

    International Nuclear Information System (INIS)

    Kim, Y.J.; Han, S.B.

    2007-03-01

    The research on evaluation methodology for high temperature components and technical issues includes the comparison of evaluation technology of Very High Temperature Reactors(VHTRs) with that of present commercial reactors, the review of Hot Gas Duct(HGD) insulation designs, the analysis of the codes related to VHTR component construction and the analysis of technical issues on application of present codes to HGD construction. Codes to assure the integrity of the VHTR components are not fully prepared yet in any country. To understand the evaluation technology of the VHTR-related codes, key requirements of ASME B and PV Code Section III, Subsection NB and NH were compared. Six kinds of HGD designs were reviewed and compared. A reference which analyzed seven kinds of present component codes were reviewed and the limitations of them were summarized. Especially it was found that the selection of materials is limited, material property data are not enough, and design analysis methodology is not fully specified

  13. Roughness Effects on Fretting Fatigue

    Science.gov (United States)

    Yue, Tongyan; Abdel Wahab, Magd

    2017-05-01

    Fretting is a small oscillatory relative motion between two normal loaded contact surfaces. It may cause fretting fatigue, fretting wear and/or fretting corrosion damage depending on various fretting couples and working conditions. Fretting fatigue usually occurs at partial slip condition, and results in catastrophic failure at the stress levels below the fatigue limit of the material. Many parameters may affect fretting behaviour, including the applied normal load and displacement, material properties, roughness of the contact surfaces, frequency, etc. Since fretting damage is undesirable due to contacting, the effect of rough contact surfaces on fretting damage has been studied by many researchers. Experimental method on this topic is usually focusing on rough surface effects by finishing treatment and random rough surface effects in order to increase fretting fatigue life. However, most of numerical models on roughness are based on random surface. This paper reviewed both experimental and numerical methodology on the rough surface effects on fretting fatigue.

  14. Design Methodology of a Sensor Network Architecture Supporting Urgent Information and Its Evaluation

    Science.gov (United States)

    Kawai, Tetsuya; Wakamiya, Naoki; Murata, Masayuki

    Wireless sensor networks are expected to become an important social infrastructure which helps our life to be safe, secure, and comfortable. In this paper, we propose design methodology of an architecture for fast and reliable transmission of urgent information in wireless sensor networks. In this methodology, instead of establishing single complicated monolithic mechanism, several simple and fully-distributed control mechanisms which function in different spatial and temporal levels are incorporated on each node. These mechanisms work autonomously and independently responding to the surrounding situation. We also show an example of a network architecture designed following the methodology. We evaluated the performance of the architecture by extensive simulation and practical experiments and our claim was supported by the results of these experiments.

  15. Rationality and irrationality in understanding human behaviour. An evaluation of the methodological consequences of conceptualising irrationality

    Directory of Open Access Journals (Sweden)

    Cosmin Toth

    2013-06-01

    Full Text Available Some of the most known and fertile models for understanding human behaviour are those which rest on the assumption of human rationality. These models have specific strategies for dealing with situations in which understanding human behaviour becomes difficult, i.e. cases of irrationality, and this, in turn, leads to particular methodological consequences. The aim of this article is to illustrate and systematize some of the typical theoretical approaches to the issues of rationality and irrationality and their methodological consequences, while warning, at the same time, against the risks of applying rationality models of a pronounced normative-evaluative nature. A number of important methodological consequences of applying the principle of charity to various degrees of strength are analysed and a taxonomic grid for the different ways of approaching rationality is presented.

  16. COMPARING AND CONTRASTING THE ALTERNATIVE METHODOLOGIES AVAILABLE FOR EVALUATING THE IMPACT OF TOURISM

    Directory of Open Access Journals (Sweden)

    Silvana DJURASEVIC

    2007-06-01

    Full Text Available Tourism has impacts upon a destination country. The aim of this work is to compare and contrast the alternative methodologies available for evaluating the impact of tourism. Tourism can be one of alternatives for development of a destination and sometimes the only possibility. For that reason it is very important to compare benefit and cost that tourism brings with corresponding valyes of alternative investment. Obtained results represent a very important input for planning and also for decision making policy. Different methodologies bring different results, different techniques have their own strenghts and weaknesses. For that reason, depending on the need, it is important to combine the methodologies in order to achieve the maximal benefit and minimal costs, from economical aspect, socio-cultural and environmental development.

  17. Use of cesium-137 methodology in the evaluation of superficial erosive processes

    International Nuclear Information System (INIS)

    Andrello, Avacir Casanova; Appoloni, Carlos Roberto; Guimaraes, Maria de Fatima; Nascimento Filho, Virgilio Franco do

    2003-01-01

    Superficial erosion is one of the main soil degradation agents and erosion rates estimations for different edaphic climate conditions for the conventional models, as USLE and RUSLE, are expensive and time-consuming. The use of cesium- 137 anthropogenic radionuclide is a new methodology that has been much studied and its application in the erosion soil evaluation has grown in countries as USA, UK, Australia and others. A brief narration of this methodology is being presented, as the development of the equations utilized for the erosion rates quantification through the cesium- 137 measurements. Two watersheds studied in Brazil have shown that the cesium- 137 methodology was practicable and coherent with the survey in field for applications in erosion studies. (author)

  18. Evaluation of fatigue crack growth in the primary circuit pipeline of a WWER 440/213c type nuclear power plant

    International Nuclear Information System (INIS)

    Samohyl, P.

    1993-07-01

    The fatigue damage of the primary circuit of WWER-440/213c reactors was evaluated proceeding from actual and design operating data of units 3 and 4 of the Bohunice V-2 nuclear power plant. A complex computation model was set up, encompassing the main circulation pipeline, pressurizer pipeline, emergency core aftercooling system pipeline, steam pipeline, and feedwater pipeline. The standardized STATIC code was applied to the stress analysis, and the FATLBB code was used to determine the crack increment for all operating states and primary circuit sections. The probability of fatigue failure of the pipelines was found to be low. (J.B.). 55 tabs., 3 figs., 9 refs

  19. Study the Cyclic Plasticity Behavior of 508 LAS under Constant, Variable and Grid-Load-Following Loading Cycles for Fatigue Evaluation of PWR Components

    Energy Technology Data Exchange (ETDEWEB)

    Mohanty, Subhasish [Argonne National Lab. (ANL), Argonne, IL (United States); Barua, Bipul [Argonne National Lab. (ANL), Argonne, IL (United States); Soppet, William K. [Argonne National Lab. (ANL), Argonne, IL (United States); Majumdar, Saurin [Argonne National Lab. (ANL), Argonne, IL (United States); Natesan, Ken [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-09-01

    This report provides an update of an earlier assessment of environmentally assisted fatigue for components in light water reactors. This report is a deliverable in September 2016 under the work package for environmentally assisted fatigue under DOE’s Light Water Reactor Sustainability program. In an April 2016 report, we presented a detailed thermal-mechanical stress analysis model for simulating the stress-strain state of a reactor pressure vessel and its nozzles under grid-load-following conditions. In this report, we provide stress-controlled fatigue test data for 508 LAS base metal alloy under different loading amplitudes (constant, variable, and random grid-load-following) and environmental conditions (in air or pressurized water reactor coolant water at 300°C). Also presented is a cyclic plasticity-based analytical model that can simultaneously capture the amplitude and time dependency of the component behavior under fatigue loading. Results related to both amplitude-dependent and amplitude-independent parameters are presented. The validation results for the analytical/mechanistic model are discussed. This report provides guidance for estimating time-dependent, amplitude-independent parameters related to material behavior under different service conditions. The developed mechanistic models and the reported material parameters can be used to conduct more accurate fatigue and ratcheting evaluation of reactor components.

  20. Seafarer fatigue

    DEFF Research Database (Denmark)

    Jepsen, Jørgen Riis; Zhao, Zhiwei; van Leeuwen, Wessel M. A.

    2015-01-01

    Background: The consequences of fatigue for the health and safety of seafarers has caused concern in the industry and among academics, and indicates the importance of further research into risk factors and preventive interventions at sea. This review gives an overview of the key issues relating...... to seafarer fatigue. Materials and methods: A literature study was conducted aiming to collect publications that address risk factors for fatigue, short-term and long-term consequences for health and safety, and options for fatigue mitigation at sea. Due to the limited number of publications that deals...... with seafarers, experiences from other populations sharing the same exposures (e.g. shift work) were also included when appropriate. Results: Work at sea involves multiple risk factors for fatigue, which in addition to acute effects (e.g., impaired cognition, accidents) contributes through autonomic, immunologic...

  1. Development of an in situ fatigue sensor.

    Science.gov (United States)

    2011-01-01

    A prototype in situ fatigue sensor has been designed, constructed and evaluated experimentally for its ability to monitor the accumulation of fatigue damage in a cyclically loaded steel structure, e.g., highway bridge. The sensor consists of multiple...

  2. Methodological Reflections on the Contribution of Qualitative Research to the Evaluation of Clinical Ethics Support Services.

    Science.gov (United States)

    Wäscher, Sebastian; Salloch, Sabine; Ritter, Peter; Vollmann, Jochen; Schildmann, Jan

    2017-05-01

    This article describes a process of developing, implementing and evaluating a clinical ethics support service intervention with the goal of building up a context-sensitive structure of minimal clinical-ethics in an oncology department without prior clinical ethics structure. Scholars from different disciplines have called for an improvement in the evaluation of clinical ethics support services (CESS) for different reasons over several decades. However, while a lot has been said about the concepts and methodological challenges of evaluating CESS up to the present time, relatively few empirical studies have been carried out. The aim of this article is twofold. On the one hand, it describes a process of development, modifying and evaluating a CESS intervention as part of the ETHICO research project, using the approach of qualitative-formative evaluation. On the other hand, it provides a methodological analysis which specifies the contribution of qualitative empirical methods to the (formative) evaluation of CESS. We conclude with a consideration of the strengths and limitations of qualitative evaluation research with regards to the evaluation and development of context sensitive CESS. We further discuss our own approach in contrast to rather traditional consult or committee models. © 2017 John Wiley & Sons Ltd.

  3. Development of a web-based fatigue life evaluation system for primary components in a nuclear power plant

    International Nuclear Information System (INIS)

    Seo, Hyong Won; Lee, Sang Min; Choi, Jae Boong; Kim, Young Jin; Choi, Sung Nam; Jang, Ki Sang; Hong, Sung Yull

    2004-01-01

    A nuclear power plant is composed of a number of primary components. Maintaining the integrity of these components is one of the most critical issues in nuclear industry. In order to maintain the integrity of these primary components, a complicated procedure is required including regular in-service inspection, failure assessment, fracture mechanics analysis, etc. Also, experts in different fields have to co-operate to resolve the integrity issues on the basis of inspection results. This integrity evaluation process usually takes long, and thus, is detrimental for the plant productivity. Therefore, an effective safety evaluation system is essential to manage the integrity issues on a nuclear power plant. In this paper, a web-based fatigue life evaluation system for primary components in nuclear power plant is proposed. This system provides engineering knowledge-based information and concurrent and collaborative working environment through internet, and thus, is expected to raise the efficiency of integrity evaluation procedures on primary components of a nuclear power plant

  4. A Methodology for Collective Evaluation and Selection of Industrial R&D Projects

    OpenAIRE

    Muhittin Oral; Ossama Kettani; Pascal Lang

    1991-01-01

    This paper proposes a methodology for evaluating and selecting R&D projects in a collective decision setting, especially useful at sectorial and national levels. It consists of two major phases: Evaluation and Selection. The evaluation process repeatedly uses mathematical programming models to determine the "relative values" of a given R&D project from the viewpoint of the other R&D projects. The selection process of R&D projects is based on these "relative values" and is done through a model...

  5. A Fatigue Crack Size Evaluation Method Based on Lamb Wave Simulation and Limited Experimental Data

    Directory of Open Access Journals (Sweden)

    Jingjing He

    2017-09-01

    Full Text Available This paper presents a systematic and general method for Lamb wave-based crack size quantification using finite element simulations and Bayesian updating. The method consists of construction of a baseline quantification model using finite element simulation data and Bayesian updating with limited Lamb wave data from target structure. The baseline model correlates two proposed damage sensitive features, namely the normalized amplitude and phase change, with the crack length through a response surface model. The two damage sensitive features are extracted from the first received S0 mode wave package. The model parameters of the baseline model are estimated using finite element simulation data. To account for uncertainties from numerical modeling, geometry, material and manufacturing between the baseline model and the target model, Bayesian method is employed to update the baseline model with a few measurements acquired from the actual target structure. A rigorous validation is made using in-situ fatigue testing and Lamb wave data from coupon specimens and realistic lap-joint components. The effectiveness and accuracy of the proposed method is demonstrated under different loading and damage conditions.

  6. The evaluation of new methodological approaches to lease reporting on the side of lessor

    Directory of Open Access Journals (Sweden)

    Hana Bohušová

    2013-01-01

    Full Text Available Since 2002 the International Accounting Standards Board (IASB and the Financial Accounting Standards Board (FASB has begun significantly cooperate in the development of standards based on the same principles. The cooperation is realised through a series of short term or long term projects. Revenue recognition and lease reporting projects represent priority areas of convergence. The development of methodological approaches for lease reporting on the side of lessee and lessor that would eliminate the main weaknesses of the current system of reporting based on the classification of lease contracts in connection with the lease term and the transfer of risks and benefits associated with the lease to the lessee should be the result of the convergence activity in the area of lease reporting. The evaluation of the impact of the newly proposed methodological approaches to lease reporting in the field of operating leases into the financial statements of lessor that will be affected by this change of methodology (financial position, comprehensive income statement is the main aim of the paper. The impact into selected indicators of financial analysis with a focus on indicators, in whose construction are used items of statements that are significantly affected by the change of the methodological approach is evaluated as well.

  7. Methodological considerations in evaluating a proliferation resistance of innovative nuclear energy systems

    International Nuclear Information System (INIS)

    Kikuchi, Masahiro; Takaki, Naoyuki; Murajiri, Masahiro; Nakagome, Yoshihiro; Tokiwai, Moriyasu

    2004-01-01

    Over 25 years ago, INFCE studied the evaluation methodology of proliferation resistance. Recently, INPRO and GEN-IV coordinated by the IAEA and the USDOE respectively seek an appropriate innovative fuel cycle system for next generation that is furnished safer, sustainable, economical and reliable features. The evaluation methodology of the proliferation resistance is also assigned as an essential part of both studies. The IAEA established and has been strictly implementing the verification measures with accurate material accountancy system from the early of the 1970s in order to detect diversion of plutonium that is individually separated from irradiated nuclear material and recycled as MOX fuel. This paper firstly identifies the impedibility of intrinsic features of innovative fuel cycles and the safeguardability of selected nonproliferation measures as two individual essential parameters for evaluation of a proliferation resistance capability. As a next step, this paper also shows methodological considerations in evaluating the proliferation resistance levels as a multiple model of several clusters that are identified the ability of each parameter. (author)

  8. Fatigue test results of flat plate specimens with surface cracks and evaluation of crack growth in structural components

    International Nuclear Information System (INIS)

    Shibata, Katsuyuki; Yokoyama, Norio; Ohba, Toshihiro; Kawamura, Takaichi; Miyazono, Shohachiro

    1982-12-01

    Part-through surface cracks are most frequently observed in the inspection of structural components, and it is one of the important subjects in the assessment of safety to evaluate appropriately the growth of such cracks during the service life of structural components. Due to the complexity of the stress at the front free surface, the crack growth at the surface shows a different behavior from the other part. Besides, an effect of interaction is caused in the growth of multiple surface cracks. These effects should be included in the growth analysis of surface part-through cracks. Authors have carried out a series of fatigue tests on some kinds of pipes with multiple cracks in the inner surface, and subsequently the fatigue test of flat plate specimens, made of Type 304L stainless steel, with a single or double surface cracks was carried out to study the basic characteristics in the growth of multiple surface cracks. Based on the results of the flat plate test. the correction factors for the front free surface (Cs) and interaction (Ci) of surface cracks were derived quantitatively by the following empirical expressions; Cs = 0.824. Ci = (0.227(a/b) 2 (sec(PI X/2) - 1) + 1)sup(1/m). Using these two correction factors, a procedure to predict the growth of surface cracks was developed by applying the crack growth formula to both the thickness and surface directions. Besides, the crack growth predictions based on the procedure of ASME Code Sex. XI, and the above procedure without the correction of the free surface and interactions on the crack growth behaviors were compared with the test results of flat plate specimens. The crack growth behavior predicted by the procedure described in this report showed the best agreement with the test results in respects of the crack growth life and the change in the crack shape. The criteria of the ASME Code did not agree with the test results. (author)

  9. Deployment evaluation methodology for the electrometallurgical treatment of DOE-EM spent nuclear fuel

    International Nuclear Information System (INIS)

    Dahl, C.A.; Adams, J.P.; Ramer, R.J.

    1998-07-01

    Part of the Department of Energy (DOE) spent nuclear fuel (SNF) inventory may require some type of treatment to meet acceptance criteria at various disposition sites. The current focus for much of this spent nuclear fuel is the electrometallurgical treatment process under development at Argonne National Laboratory. Potential flowsheets for this treatment process are presented. Deployment of the process for the treatment of the spent nuclear fuel requires evaluation to determine the spent nuclear fuel program need for treatment and compatibility of the spent nuclear fuel with the process. The evaluation of need includes considerations of cost, technical feasibility, process material disposition, and schedule to treat a proposed fuel. A siting evaluation methodology has been developed to account for these variables. A work breakdown structure is proposed to gather life-cycle cost information to allow evaluation of alternative siting strategies on a similar basis. The evaluation methodology, while created specifically for the electrometallurgical evaluation, has been written such that it could be applied to any potential treatment process that is a disposition option for spent nuclear fuel. Future work to complete the evaluation of the process for electrometallurgical treatment is discussed

  10. The Researching on Evaluation of Automatic Voltage Control Based on Improved Zoning Methodology

    Science.gov (United States)

    Xiao-jun, ZHU; Ang, FU; Guang-de, DONG; Rui-miao, WANG; De-fen, ZHU

    2018-03-01

    According to the present serious phenomenon of increasing size and structure of power system, hierarchically structured automatic voltage control(AVC) has been the researching spot. In the paper, the reduced control model is built and the adaptive reduced control model is researched to improve the voltage control effect. The theories of HCSD, HCVS, SKC and FCM are introduced and the effect on coordinated voltage regulation caused by different zoning methodologies is also researched. The generic framework for evaluating performance of coordinated voltage regulation is built. Finally, the IEEE-96 stsyem is used to divide the network. The 2383-bus Polish system is built to verify that the selection of a zoning methodology affects not only the coordinated voltage regulation operation, but also its robustness to erroneous data and proposes a comprehensive generic framework for evaluating its performance. The New England 39-bus network is used to verify the adaptive reduced control models’ performance.

  11. Methodology for the economic evaluation of cogeneration/desalination options: A user's manual

    International Nuclear Information System (INIS)

    1997-01-01

    The Methodology for the Economic Evaluation of Cogeneration/Desalination Options is suitable for economic evaluations and screening analyses of various desalination and energy source options. The methodology, based on the spreadsheet, includes simplified models of several types of nuclear/fossil power plants, nuclear/fossil heat sources, and both distillation and membrane desalination plants. Current cost and performance data have already been incorporated so that the spreadsheet can be quickly adapted to analyze a large variety of options with very little new input data required. The spreadsheet output includes the levelized cost of water and power, breakdowns of cost components, energy consumption and net saleable power for each selected option. Specific power plants can be modeled by adjustment of input data including design power, power cycle parameters and costs

  12. A Methodology for Evaluating the Hygroscopic Behavior of Wood in Adaptive Building Skins using Motion Grammar

    Science.gov (United States)

    El-Dabaa, Rana; Abdelmohsen, Sherif

    2018-05-01

    The challenge in designing kinetic architecture lies in the lack of applying computational design and human computer interaction to successfully design intelligent and interactive interfaces. The use of ‘programmable materials’ as specifically fabricated composite materials that afford motion upon stimulation is promising for low-cost low-tech systems for kinetic facades in buildings. Despite efforts to develop working prototypes, there has been no clear methodological framework for understanding and controlling the behavior of programmable materials or for using them for such purposes. This paper introduces a methodology for evaluating the motion acquired from programmed material – resulting from the hygroscopic behavior of wood – through ‘motion grammar’. Motion grammar typically allows for the explanation of desired motion control in a computationally tractable method. The paper analyzed and evaluated motion parameters related to the hygroscopic properties and behavior of wood, and introduce a framework for tracking and controlling wood as a programmable material for kinetic architecture.

  13. Development and evaluation of an intervention aiming to reduce fatigue in airline pilots: design of a randomised controlled trial

    NARCIS (Netherlands)

    van Drongelen, A.; van der Beek, A.J.; Hlobil, H.; Smid, T.; Boot, C.R.L.

    2013-01-01

    Background: A considerable percentage of flight crew reports to be fatigued regularly. This is partly caused by irregular and long working hours and the crossing of time zones. It has been shown that persistent fatigue can lead to health problems, impaired performance during work, and a decreased

  14. Evaluation methodology for tariff design under escalating penetrations of distributed energy resources

    OpenAIRE

    Abdelmotteleb, I.I.A.; Gómez, Tomás; Reneses, Javier

    2017-01-01

    As the penetration of distributed energy resources (DERs) escalates in distribution networks, new network tariffs are needed to cope with this new situation. These tariffs should allocate network costs to users, promoting an efficient use of the distribution network. This paper proposes a methodology to evaluate and compare network tariff designs. Four design attributes are proposed for this aim: (i) network cost recovery; (ii) deferral of network reinforcements; (iii) efficient consumer resp...

  15. A methodology for the security evaluation within the third-party Android marketplaces

    OpenAIRE

    Buchanan, William J.; Chiale, Simone.; Macfarlane, Richard.

    2017-01-01

    This paper aims to evaluate possible threats with unofficial Android marketplaces, and geo localize the malware distribution over three main regions: China, Europe; and Russia. It provides a comprehensive review of existing academic literature about security in Android focusing especially on malware detection systems and existing malware databases. Through the implementation of a methodology for identification of malicious applications it has been collected data revealing a 5% of them as mali...

  16. Methodology to evaluate the site standard seismic motion for a nuclear facility

    International Nuclear Information System (INIS)

    Soares, W.A.

    1983-03-01

    An overall view of the subjects involved in the determination of the site standard seismic motion to a nuclear facility is presented. The main topics discussed are: basic priciples of seismic instrumentation; dynamic and spectral concepts; design earthquakes definitions; fundamentals of seismology; empirical curves developed from prior seismic data; avalable methodologies and recommended procedures to evaluate the site standard seismic motion. (E.G.) [pt

  17. Methodology for the evaluation of a 4000-home geothermal heat pump retrofit at Fort Polk, Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, P.J.; Shonder, J.A.; White, D.L.; Huang, H.L.

    1998-03-01

    The US Army and a private energy service company are developing a comprehensive energy efficiency project to upgrade the family housing at Fort Polk, Louisiana. The project includes converting the space conditioning systems of more than 4,000 housing units to geothermal (or ground-source) heat pumps (GHPs). This interim report describes the methodology of the evaluation associated with this project, including the field monitoring that has been conducted at the base.

  18. Thermal Fatigue Evaluation of Pb-Free Solder Joints: Results, Lessons Learned, and Future Trends

    Science.gov (United States)

    Coyle, Richard J.; Sweatman, Keith; Arfaei, Babak

    2015-09-01

    Thermal fatigue is a major source of failure of solder joints in surface mount electronic components and it is critically important in high reliability applications such as telecommunication, military, and aeronautics. The electronic packaging industry has seen an increase in the number of Pb-free solder alloy choices beyond the common near-eutectic Sn-Ag-Cu alloys first established as replacements for eutectic SnPb. This paper discusses the results from Pb-free solder joint reliability programs sponsored by two industry consortia. The characteristic life in accelerated thermal cycling is reported for 12 different Pb-free solder alloys and a SnPb control in 9 different accelerated thermal cycling test profiles in terms of the effects of component type, accelerated thermal cycling profile and dwell time. Microstructural analysis on assembled and failed samples was performed to investigate the effect of initial microstructure and its evolution during accelerated thermal cycling test. A significant finding from the study is that the beneficial effect of Ag on accelerated thermal cycling reliability (measured by characteristic lifetime) diminishes as the severity of the accelerated thermal cycling, defined by greater ΔT, higher peak temperature, and longer dwell time increases. The results also indicate that all the Pb-free solders are more reliable in accelerated thermal cycling than the SnPb alloy they have replaced. Suggestions are made for future work, particularly with respect to the continued evolution of alloy development for emerging application requirements and the value of using advanced analytical methods to provide a better understanding of the effect of microstructure and its evolution on accelerated thermal cycling performance.

  19. Near threshold fatigue testing

    Science.gov (United States)

    Freeman, D. C.; Strum, M. J.

    1993-01-01

    Measurement of the near-threshold fatigue crack growth rate (FCGR) behavior provides a basis for the design and evaluation of components subjected to high cycle fatigue. Typically, the near-threshold fatigue regime describes crack growth rates below approximately 10(exp -5) mm/cycle (4 x 10(exp -7) inch/cycle). One such evaluation was recently performed for the binary alloy U-6Nb. The procedures developed for this evaluation are described in detail to provide a general test method for near-threshold FCGR testing. In particular, techniques for high-resolution measurements of crack length performed in-situ through a direct current, potential drop (DCPD) apparatus, and a method which eliminates crack closure effects through the use of loading cycles with constant maximum stress intensity are described.

  20. A methodology for evaluating land suitability for medicinal plants at a regional level

    Directory of Open Access Journals (Sweden)

    Marco Barbaro

    2011-12-01

    Full Text Available Before introducing a new crop in an area, such as medicinal plant species, crop-land suitability analysis is a prerequisite to achieve an optimum exploitation of the available land resources for a sustainable agricultural production. To evaluate the land suitability it is important to take into account the habitats of the plant species. Moreover, agronomic, logistic and product quality aspects have to be considered. The importance of these aspects changes according to the stakeholders: the local government is more involved in supporting environmental suitability and production sustainability, farmers need areas which satisfy agronomic and logistic requirements, while industry is interested in the quality of production. A methodology was developed and implemented to create suitability maps for medicinal plants. Because of the generally limited information about medicinal plant adaptation, a simple methodology, based on a priori information has been developed, based on three different criteria: i environmental suitability (point of view of local government; ii agronomic, productivity and logistic suitability (point of view of the farmer; iii quality suitability (point of view of industry. For each of the three criteria, a specific macro-indicator, based on land characteristics, was calculated using membership functions. Here, a methodology to create maps for the introduction of such species was developed and implemented. This methodology can be repeated by command scripts in an easy-to-use freeware GIS. The structure of the evaluation model can be easily adapted to consider more detailed land information like climate and soil. The methodology (implemented by scripts in a freeware GIS, can be easily repeated and adapted for other situations.